大鼠烫伤后早期肝细胞变化的超微结构观察及形态计量分析

用超微结构形态计量方法分析了大鼠30％烫伤后早期肝细胞超微结构的变化规律。烫伤后,肝细胞内精原迅速减少,至6小时,几乎全部消失。烫伤后2小时、6小时。肝细胞内溶酶体的体积密度、数目密度和平均体积均明显增大。线粒体于烫伤后半小时出现基质密度增加、嵴扩张,烫伤后2小时、6小时,线粒体肿胀,其体积密度、平均体积增大。实验结果提示:在严重烧伤后数小时内,肝细胞的超微结构即出现明显的改变。本文对出现这些变化的机制进行了讨论。     

Ultrastructural changes during acute acetaminophen-induced hepatotoxicity in the mouse: a time and dose study

This study was undertaken to evaluate the early ultrastructural changes during the development of acetaminophen hepatotoxicity. Doses at or near the threshold for hepatotoxicity were selected to permit comparison of early reversible effects to those which ultimately progressed to necrosis in the absence of early agonal effects or drug-induced mortality. Both 300- and 600-mg/kg doses resulted in similar declines in hepatic glutathione levels to 14 and 22% of control values, respectively, by 2 hours, with more rapid recovery after the low dose. Plasma sorbitol dehydrogenase activity was elevated after 600 mg/kg but not after 300 mg/kg. During the first 2 hours after acetaminophen there was cytomegaly with rapid progression to necrosis after 600 mg/kg but minimal progression after 300 mg/kg. Ultrastructurally, vesiculation, vacuolation and mitochondrial and plasma membrane degeneration culminated in scattered single cell death by 4 hours and widespread centrilobular necrosis by 8 hours after 600 mg/kg. The time course of lesion development was slower after 300 mg/kg with damage restricted to the first two to three rows of centrilobular cells and limited numbers of isolated necrotic cells by 8 hours. By 18 to 24 hours livers of mice given 300 mg/kg appeared normal. Results are consistent with the endoplasmic reticulum being the site of acetaminophen activation and initial attack. However, early ultrastructural changes in mitochondria and plasma membrane observed after the high dose were not prominent after the low dose. This suggests that early acetaminophen damage to these organelles may play a critical role in acetaminophen hepatotoxicity.     

Stability and autolysis of cortical neurons in post-mortem adult rat brains

We investigated the dynamics of autolytic damage of the cortical neurons in adult brains for 24 hours at room temperature (+20 degrees C) after cardiac arrest. The progressive histological and ultrastructural changes were documented using routine and immunohistochemical staining as well as electron microscopy. Our results demonstrated that there were no autolytic damages in the ultrastructure of cerebral neurons in the first 6 hours after warm cardiac arrest, in agreement with previous studies in other mammals. Interestingly, the activation of caspase-3 was observed in a significant number of neurons of the cerebellum and neocortex 9 hours following cardiac arrest. No significant changes related to autolysis were observed using amnio-cupric acid and Nissl (thionine) staining.     

Osteoclast cell-surface specializations and nuclear kinetics during egg-laying in Japanese quail

Medullary bone deposits serve as a reservoir of labile calcium for egg-shell calcification in birds. Quantitative transmission-electron-microscope methods and light-microscope autoradiographic cell-population-kinetic analyses were used to determine changes in cell-surface specializations and population dynamics of medullary bone osteoclasts during egg-laying in Japanese quail. Prior to egg-shell formation, from 0 to about 8 hours after the previous oviposition, very few osteoclast profiles had ruffled borders. The appearance of ruffled borders coincided with the beginning of egg-shell calcification, about 9-10 hours after the previous oviposition. During egg-shell calcification, from about 10-21 hours after the previous oviposition, most osteoclast profiles had ruffled borders. Ruffled borders disappeared at the completion of egg-shell calcification and commencement of egg-shell pigmentation. Thus, functional activities of medullary bone osteoclasts appear to be closely synchronized with egg-shell calcification during egg-laying. From 1 to 48 hours after a single injection of ³H-thymidine (³H-TdR), very few labeled osteoclast nuclei were seen during egg-laying. Following multiple injections of ³H-TdR, the percentage of labeled nuclei reached a peak at about 170 hours after the first injection. At this peak-labeling time, relatively few of the osteoclast profiles that had labeled nuclei had two or more; although the average number of nuclei per osteoclast profile was about 3.6. These kinetic data suggest that the medullary bone osteoclast population has a prolonged rate of turnover compared to rapid changes in cell activities associated with each 24-hour egg-laying cycle; and collectively they would suggest that rapid changes in osteoclast functions occur independently of changes in cell-population dynamics.     

Gross and cellular analysis of 6-mercaptopurine-induced cleft palate in hamster

The present study analyzes the morphological, histochemical, and ultrastructural aspects of the pathogenesis of 6-mercaptopurine (6MP)-induced cleft palate in hamster fetuses. Gross and light microscopic observations indicated that 6MP stunts the growth of vertical palatal shelves and thus induces cleft palate. Ultrastructural analysis showed that, in contrast to controls, 6MP-induced alterations were first seen in the mesenchymal cells 24 hr after drug administration. The initial alterations were characterized by swelling of the nuclear membrane. During the next 12 hr, lysosomes were seen first in the mesenchymal cells and then in the cells of the medial edge epithelium (MEE) of the developing palatal primordia. The appearance of lysosomes was temporally abnormal and was interpreted as a sublethal response to 6MP treatment. Subsequently, the nuclear alterations and the lysosomes diminished; and 48 hr after 6MP administration, they were absent from the palatal tissues. Ninety hours after 6MP administration, unlike the controls (in which the palatal shelves were already fused), changes were seen at the epithelial-mesenchymal interface in the developing cleft palatal shelves. These changes were characterized by breakdown of the basal lamina and epithelial-mesenchymal contacts. Eventually, at term, the MEE of the vertical shelf stratified. It was suggested that 6MP affected cytodifferentiation in the palatal tissues during the critical phase of early vertical shelf development and thereby induced cleft palate.     

Ultrastructure of the pinealocytes in rats exposed to light and radiation

Changes in pinealocytes (PC) were analysed using quantitative electron microscopy in 240 adult male rats from first minutes up to 180 days after their continuous exposure to bright light (CLE) for 48 hours, X-ray irradiation (XRI) or their combination (CE). After CLE early changes of PC included the reduction of rough endoplasmic reticulum (RER), Golgi complex and synaptic ribbons. At 24 hours and 10 days PC secretory activity was increased, while their ultrastructural organization was normalized by 30-180 days. 10 days after XRI degenerative changes were detected in PC that included dilation, fragmentation and vacuolization of RER cisterns, mitochondrial swelling, appearance of large vacuoles and osmiophilic inclusions, increase in lysosome content. Volume density of mitochondria and RER was lower, while that of Golgi complex was higher than in control. PC ultrastructure was restored 30-180 days after XRI. Following CE, the changes in PC ultrastructural organization were more significant at all time interval studied than after the action of single factors. The results obtained indicate that CLE increased the extent of postradiation changes in PC ultrastructural organization during the early time intervals after XRI and at the peak of radiation sickness development.     

家兔急性肺栓塞对肺血管内皮细胞超微结构及血清一氧化氮含量的影响

目的 探讨急性肺栓塞（APE）对肺血管内皮细胞（PVECs）的结构及血清一氧化氮（NO）含量的影响。 方法 19只日本大耳兔,随机分成假手术组、栓塞2 h、4 h组(n=3)和8 h组（n=10）。通过输入自体血栓建立家兔急性肺栓塞模型后,采用HE染色光学显微镜下观察肺的病理组织学变化;透射电子显微镜下观察PVECs在肺栓塞2 h、4 h及8 h的超微结构变化;硝酸还原酶法测定相应时间点血清NO含 结果 HE染色显示栓塞组肺动脉内有血栓,肺间质炎性病变,肺淤血;透射电子显微镜显示,栓塞组PVECs水肿、破裂,线粒体肿胀,内质网空泡化,并随栓塞时间延长PVECs出现坏死脱落,细胞器溶解。肺栓塞2 h、4 h和8 h血清NO含量均低于栓塞前,与栓塞前比较差异有显著性意义（P＜0.05）。 结论 家兔APE可致PVECs超微结构改变和血清NO含量下降,且两者间关系密切。     

Ultrastructural Autoradiographic Studies of the Early Vasoproliferative Response in Tumor Angiogenesis

The early local vasoproliferative response induced by live tumor cells and an extract derived from such cells was studied in rat subcutaneous tissue by means of electron microscopy and ultrastructural autoradiography after local injections of tritium-labeled thymidine. DNA synthesis was localized in endothelial cells, pericytes, and perivascular cells 6 to 8 hours after exposure to 10⁶ live Walker ascites tumor cells. At this time, DNA-synthesizing endothelial cells in parent vessels exhibited a continuous basement membrane and could not be readily differentiated, ultrastructurally, from control endothelium. At 48 to 50 hours, the number of labeled cells increased and there was ultrastructural evidence of regenerating endothelium: marked increase in ribosomes and endoplasmic reticulum, scarce or absent pinocytotic vesicles, attenuated or discontinuous basement membrane and marked irregularities in cytoplasmic surfaces. Labeled endothelial cells were present in parent vessels, as well as along newly formed sprouts. Autoradiographic and ultrastructural findings after tumor extract or live tumor cells at 48 hours were similar. Evidence was also presented that cells which were recognizable as pericytes, by ultrastructural criteria and by their localization within the basement membrane, were capable of DNA synthesis and mitosis.     

Unsuspected analgesic nephropathy in transitional cell carcinoma of the upper tract: a morphological study

Analgesic nephropathy is known to have a high incidence in Australia where, following the experience in Scandinavia, reports have been published for some time recording the association between analgesic nephropathy and urothelial malignancies. The morbid anatomical features of analgesic nephropathy are now sufficiently well accepted to allow a retrospective study of unselected nephrectomies for transitional cell carcinoma of the renal pelvis and ureter, in order to assess the incidence of analgesic-type changes in this well defined group of malignancies. The records of a large general histopathology department between 1972–1978 were searched and 24 consecutive transitional cell carcinomas in these sites treated by nephrectomy were selected for study. Of these, 21 were suitable for assessment and on review were shown to comprise 11 cases with papillary changes acceptable as analgesic in type and five which were suggestive of early analgesic change. Of these 16, seven were female, only two were known analgesic abusers and five were recorded as consuming analgesics on a regular basis. These findings suggest that analgesics may play a significant role in the pathogenesis of urothelial malignancy in the general population.     

3-氯丙二醇及2,3-氧丙醇合并给药对大鼠附睾、肝、肾超微结构的影响

以每日5mg/kg的3-氯丙二醇及75mg/kg的2,3-氧丙醇同时给大鼠灌胃,连续给药2天后停药8天,共10天为一疗程。观察了3,6,9疗程结束时,附睾起始部主细胞的超微结构改变,及附睾管起始部的精子和肝脏、肾脏的超微结构。发现在3、6疗程末,附睾主细胞的高尔基复合体扁平囊变窄,大泡皱缩。在6疗程末,细胞表面的吞饮小泡和静纤毛减少。仅在3疗程见到粗面内质网扩张。9疗程的超微结构与对照比较无明显区别。结果提示,每一疗程药物引起的附睾主细胞超微结构的改变,在多数动物是可恢复的。但由于个体差异,部分动物于疗程之末,尚未完全恢复。在第6疗程末的肝脏,有部分肝细胞滑面内质网扩张,线粒体体积缩小,基质电子密度增高。这些变化可能是一种轻度的细胞损伤,这种损伤在3,9疗程均未发现,说明它与疗程长短不呈平行关系。肾尿细管上皮细胞及附睾起始部精子的超微结构,无可见改变。这一结果为阐明3-氯丙二醇及2,3-氧丙醇合并用药的抗生育作用,及对有关内脏的毒性作用,提供了形态学的依据。     

Light and electron microscopic observations on granulomatous lesions in pigs dosed with Mycobacterium intracellulare

The histology and ultrastructure of the granulomatous lesions were studied in 18 pigs dosed orally with Mycobacterium intracellulare serotype 8. The pigs were killed 2, 4, 6, 8 and 12 weeks after dosing. Histologically, initial granulomatous lesions were seen in the tonsils 6 and 8 weeks after dosing. Initial or more advanced granulomatous lesions were observed in the tonsils and lymph nodes (mandibular, jejunal, ileocolic and superficial inguinal) 12 weeks after dosing. The initial granulomatous lesions appeared as slight proliferations of epithelioid cells and multinucleated giant cells. Advanced granulomatous lesions were nodular proliferations of epithelioid cells and multinucleated giant cells (epithelioid-cell nodule). In more advanced granulomatous lesions, the epithelioid-cell nodules increased in size and showed caseation necrosis, calcification and fibrosis. Ultrastructural examination revealed that the epithelioid-cell nodules consisted of mononuclear cells, epithelioid cells and multinucleated giant cells. In the caseous foci of the epithelioid-cell nodules, an electron-dense amorphous material with collagen fibres was deposited in the intercellular spaces. Although a small number of acid-fast organisms were observed histologically, they could not be detected ultrastructurally. The histological and ultrastructural findings of the present cases are compared with those of pigs infected with M. avium and with human lesions of tuberculosis and sarcoidosis.     

Acute calcium nephrotoxicity. An electron microscopical and semiquantitative light microscopical study.

Rats were infused for three hours with doses of calcium gluconate to elevate serum calcium level and were killed either immediately after infusion or after 24 hours. Necrosis of proximal tubular cells was observed when serum calcium level was 16.0 mg/dl or higher. Above 16.0 mg/dl, an additional 5% of renal tubular profiles contained damaged cells for each 1 mg/dl in serum calcium. No difference in extent of damage was found in rats killed immediately or after 24 hours. Initial changes were formation of granular dense bodies in mitochondria, cell swelling, rupture, and extensive mitochondrial calcification. Renal tubular basement membrane changes appeared to be initiated by protrusion of cytoplasmic buds, forming ovoid bodies, which became embedded in the basement membrane. These ovoid bodies then appeared to serve as a nidus for further extensive basement membrane calcification.     

Comprehensive one-day renal function testing in man

A comprehensive one-day renal function test consisting of a single outpatient visit lasting nine hours, with a minimum of time off work or away from home, is described in detail. Although a large number of laboratory tests are performed in one day, patients usually appreciate thoroughness, and the cost is more than offset by the saving in occupancy of hospital beds and by the early and precise diagnosis of reversible aspects of renal disease. Some aspects of improved methodology, such as the sequential determination of minimum urinary pH, bicarbonate, titratable acid, ammonium, and total acid on a single sample using an automatic titrator, are given in detail. Clinical application of the comprehensive nine-hour renal function testing system is illustrated by the result sheet of a patient with analgesic nephropathy, who was shown in one day to have secondary severe renal failure (glomerular filtration rate 20% of normal for age and surface area), renal tubular acidosis of the distal gradient type (minimum urinary pH 6.20), increased urinary white cell excretion rate, hyaline casts, and absence of red cell casts, consistent with a diagnosis of analgesic nephropathy and urinary tract inflammation. Normal values with 95% range for this laboratory are also given. This testing system has been found to be very useful in investigating patients with analgesic nephropathy, renal tubular acidosis, and after renal transplantation.     

Comparative study of calcified changes in aortic valvular diseases.

Calcification of the aortic valve leads to stenosis or regurgitation or both. To clarify the mechanism of heart valve calcification, comparative studies using histological and ultrastructural examinations were performed of calcified aortic valves. These valves were obtained at valve replacement surgery from 11 patients with rheumatic aortic valvular disease (RAVD), 10 patients with degenerative aortic valve disease (DAVD), and 10 patients with congenitally bicuspid aortic valves (CBAV). For electron microscopic study, 5 cases were selected from each group. In RAVD, histological examination revealed calcification in a degenerated amorphous area at the center of fibrous thickened regions and in laminar fibrous thickened areas near the valve surface. In DAVD, calcification was observed mainly in the fibrosa near the valve ring. In CBAV, basic pathological changes were similar to those in DAVD; however, additional severe calcification of the raphe was observed, if the raphe was present. Ultrastructural examinations showed deposition of electron-dense materials in two patterns in all three groups; one pattern was observed in the interfibrillar spaces of collagen fibrils, and the other pattern was widespread macular deposition unrelated to the preexisting structure. In RAVD, microfibril-like fibrillar structures were found in the areas of deposition of electron-dense materials. These findings suggest that newly formed connective tissue degraded and became necrotic because of nutritional deprivation, especially in the thickened central area, causing calcium deposition. In DAVD and CBAV, numerous lipid vacuoles were found in the electron-dense deposition areas similar to lipid deposition in aortic atherosclerosis. Localized calcium deposition in the fibrosa suggests that the stress of valvular motion and pressure load induces sclerotic changes with the degeneration of collagen fibers, providing a core for calcification. In CBAV, the raphe was the main location of calcification, wherein spiraled collagen fibrils were observed. Increasing the hemodynamic load with abnormal structure might influence calcification. The ultrastructural pattern of calcification of the valve is common; however, additional findings suggest that the cause and mechanism are different in each type of heart valve disease.     

Ultrastructural and biochemical aspects of liver mitochondria during recovery from ethanol-induced alterations. Experimental evidence of mitochondrial division.

To study the morphologic and biochemical changes occuring in liver mitochondria during recovery from ethanol-induced injury, rats fed a 6-month high-alcohol regimen plus a nutritionally adequate diet which did not induce fatty liver were compared with isocalorically fed controls. After this period the alcohol-fed animals displayed striking ultrastructural changes of liver mitochondria and a decreased respiratory activity with succinate or malate-glutamate as substrate. On the contrary, the respiratory rate with I-glycerophosphate was 50% increased. Regression changes were studied after alcohol was withdrawn from the diet. Enlarged mitochondria rapidly disappeared (in 24 hours), although a few megamitochondria were still present after 8 days of abstinence. A similar recovery was observed for the functional alterations. At the end of the experimental period, only a slight decrease of the maximal respiratory rate using malate-glutamate as a substrate was noted. The ultrastructural findings and the morphometric data suggest that the way in which mitochondrial normalization takes place is based on partition of these organelles.     

Experimental analgesic nephropathy: changes in renal structure and urinary concentrating ability in Fischer 344 rats given continuous low doses of aspirin and paracetamol

Long-term treatment with aspirin and paracetamol produced renal papillary necrosis in female Fischer 344 rats. Aspirin (230 mg/kg body weight/day) and paracetamol (380 mg/kg body weight/day) were dissolved in drinking water and given continuously for up to 65 weeks. Renal morphological changes were examined between 21 weeks and 65 weeks of commencement of analgesic treatment using light and electron microscopy, and were compared with age-matched controls. Structural damage initially occurred in the mid-papillary region, and specifically involved the interstitial cells and interstitial matrix. Necrosis of the epithelium of the thin limbs of the loop of Henle was present only after interstitial changes were well established. Cortical interstitial fibrosis and tubular atrophy occurred after renal papillary changes were observed. There was no evidence of significant vascular damage. Urinary concentrating ability was measured sequentially during the period of analgesic treatment. A decrease in urine concentrating ability was present when early changes to the interstitial cells and matrix were observed, and concentrating ability continued to decrease in parallel with increasing morphological damage. This study describes an animal model of analgesic-induced nephropathy, enabling early morphological changes to be studied and correlated with renal functional changes.     

Early ultrastructural changes of antral mucosa with aspirin in the absence of Helicobacter pylori.

AIMS--To describe the ultrastructural changes that occur in human antral mucosa following direct application of aspirin in volunteers without Helicobacter pylori infection. METHODS--Ten healthy male volunteers without H pylori infection underwent three consecutive endoscopies (at zero, one and five hours). At the first endoscopy, two biopsy specimens were obtained (one for histology and the other for electron microscopy (EM)). At subsequent endoscopies, a single biopsy specimen was obtained for EM. A 50 ml solution of aspirin (concentration 3 mg/ml) was applied to the antral mucosa at the first endoscopy in five subjects; the other five subjects received 50 ml distilled water (placebo). RESULTS--The ultrastructural appearance of the first biopsy specimen in all subjects and subsequent biopsy specimens in the placebo treated subjects was normal. The aspirin treated group had evidence of intercellular oedema, widening of capillary fenestrae, rupturing of apical membranes, and dilatation of endoplasmic reticulum and mitochondria after one hour; these changes were more marked at five hours. Tight junctions were maintained. CONCLUSION--This is the first study to describe the early ultrastructural changes in antral mucosa induced by aspirin in subjects without H pylori infection.     

Analgesic-associated nephropathy

Summary Although the question of whether or not analgesic abuse leads to a certain type of nephropathy has been investigated since 1953, no conclusive answer has been forthcoming. Epidemiologic investigations on the correlation between analgesic abuse and renal function as well as experimental animal studies have given contradictory results concerning the possibility of analgesic-associated kidney damage. However, studies on the correlation between analgesic abuse and papillary necrosis have demonstrated that this lesion coincides in 69% of the cases with an analgesic history. Follow-up studies of patients with analgesic nephropathy have shown that renal function deteriorates in 60% of the patients with continued abuse and that it stabilizes in 80% of the patients after cessation of abuse. Studies on the legislative restriction of phenacetin/acetaminophen, carried out mostly in Scandinavian countries since 1965, show a 50%–90% decline in signs of analgesic nephropathy (papillary necrosis) following a reduction in the sale of these drugs. The prevalence of analgesic abuse may be underestimated, since up to 80% of the abusers tend to deny their analgesic intake. Obviously, only a small percentage of analgesic abusers (approximately 1%) finally develop nephropathy. Even though the results of epidemiologic and experimental studies are contradictory, the results of investigations on papillary necrosis and on legislative prevention as well as of patient follow-ups tend to indicate a correlation between analgesic abuse and a well-defined type of nephropathy.Abbreviations AAN analgesic-associated nephropathy - AA analgesic abuse - PN renal papillary necrosis     

AKP与生物瓣钙化的研究Ⅱ从植入材料的组织学变化研究AKP与生物瓣钙化的关系

本文在血磷与生物材料钙化关系的研究基础上,从生物瓣材料植入体内后的组织学变化,探讨了ＡＫＰ与生物瓣钙化的关系。组织学和超微结构研究表明：生物瓣组织在植入体内后有进行性形态学变化,包括形成包囊,刺激组织增生和细胞浸润,包囊诱使细胞变性,细胞在变性中使ＡＫＰ活力升高,变性和坏死细胞的降解成分便成为钙结晶的成核部位;ＡＫＰ使局部ＰＯ３－４积累,促进钙化发生。由此本文探讨了生物瓣钙化中ＡＫＰ的发生机理和ＡＫＰ与钙化的关系。