Morphological changes in the liver cells of rabbits with a bacterial infection

In the process of bacterial infection in rabbits, their livers have been studied by means of light and electron microscopy, as well as by morphometric analysis. The results evidence pathomorphologic and ultrastructural changes occurring in liver cells. These changes, probably, cause different metabolic disturbances and thus facilitate the development of destructive processes in vital organs.     

Clinical utility of red cell distribution width in alcoholic and non-alcoholic liver cirrhosis

Red blood cell distribution width (RDW) is a measure of the variation of red blood cell width that is reported as apart of standard complete blood count. Red blood cell distribution width results are often used together with mean corpuscular volume (MCV) results to figure out mixed anemia. The aim of our study was to compare the values of RDW in alcoholic and non-alcoholic liver cirrhosis and to determine if RDW follows the severity of disease according to Child-Pugh score. We retrospectively analyzed 241 patients (176 men and 65 women) with liver cirrhosis and anemia, defined as a hemoglobin value < 130 g/L in men and < 120 g/L in women, which were hospitalized in our Division in a period between 2006 and 2008. Patients were divided in two groups; in first were patients with alcoholic liver cirrhosis, and in second with non-alcoholic cirrhosis. Severity of disease was determined according to Child-Pugh score. Red blood cells distribution width Normal reference range is 11-15%. Alcoholic liver cirrhosis had 204 patients (85%) while non-alcoholic cirrhosis had 37 patients (15%). In group of alcoholic cirrhosis the average RDW was 16.8%. In relation to severity of disease the average RDW for Child-Pugh A was 16.80%, for Child-Pugh B was 16.92%, for Child-Pugh C was 17.10%. In the group of non-alcoholic cirrhosis the average RDW was 16.73% and in relation to severity of disease for Child-Pugh A was 16.25%, for Child-Pugh B 17.01% and for Child-Pugh C was 16.87%. We didn't find statistically significant difference of RDW between alcoholic and non alcoholic cirrhosis (p > 0.05) and we didn't proved any statistically significant increase of RDW in relation to severity of disease in group of alcoholic cirrhosis (p = 0.915) nor in group of patients with non-alcoholic cirrhosis (p = 0.697). Our study showed that RDW had not any clinical value in differentiation of anemia neither in alcoholic and non-alcoholic liver cirrhosis nor in severity of liver disease.     

Effect of moderately low and low temperatures on cellular and intracellular structures of the liver

Initial stages of the rat liver ultrastructural rearrangements after local cooling of the liver tissue down to 93 K and 243 K have been studied by means of light microscopic analysis, transmission electron microscopy and freeze-substitution. The main stages in the development of cell dystrophic changes during cryonecrosis formation in the cooled area have been outlined, the crystallization behaviour und cooling conditions studied has been described.     

Morphofunctional analysis of zinc-accumulating capacity of digestive system organs]

The distribution of zinc and related changes have been studied in zinc--loaded chick pancreas, ileum and liver at the ultrastructural level by sulphide--silver method. White Leghorn chicks fed a high zinc diets (50, 500, 1000, 2000 and 4000 mgZn/kg diet) for 6 weeks, were killed at intervals; portions of their organs were fixed for light and electron microscopy; other samples were analyzed for zinc by AA spectrophotometry. A drastic increase of zinc level in chick pancreas fed 2000 mg Zn/kg diet (as ZnCl2) was associated with acinar cell degeneration. Apoptosis was the predominant form of acinar cell deletion. This study provides support for a previously proposed theory that cell injury stimulates passive zinc accumulation.     

甲基苯丙胺中毒小鼠脑组织神经元超微结构变化的研究

目的：通过观察甲基苯丙胺中毒后小鼠脑组织超微结构的改变,探讨脑组织超微结构改变与甲基苯丙胺神经毒性机制的关系。方法：将40只小鼠随机分为对照组和3组实验组（A,B,C）。A组给予MA（20mg/kg,ip,single）、B组给予MA（20mg/kg,8am,8pm,ip×2d）、C组给予MA（20mg/kg,8am,8pm,ip×4d）,对照组给予等量生理盐水。用电镜观察前额叶皮质、海马、纹状体三个部位组织神经元胞体超微结构改变,并与空白对照组比较,结果进行统计学处理。结果：给予MA后,小鼠各脑区神经元胞体出现神经元固缩、变性、凋亡、坏死等超微病变。结论：MA可诱导神经细胞发生神经元固缩、变性、凋亡、坏死等超微病变,其变化程度随时间和药物蓄积有逐渐增加的趋势。     

Morphologic and histochemical indices of hepatic function following bilateral subdiaphragmatic vagotomy

A complex morpho-functional investigation of the rat liver was performed after bilateral subdiaphragmal vagotomy by means of light, electron microscopy methods and a quantitative histochemical method. Some ultrastructural disorders in hepatocytes and in stellate reticuloendotheliocytes were revealed, with their maximal manifestation 7 days after vagotomy. At later stages (45 and 90 days), compensatory-restorative processes develop resulting in considerable (but not complete) normalization of the organ's structure. Quantitative histochemical investigations have demonstrated that even at the highest degree of the resulted disorders the liver preserves its ability to synthesize and accumulate glycogen, but the intensity of the process is considerably lowered. Functional changes are reversible in their character and correlate to the degree of structural disorders.     

Localization of hepatitis A antigen in liver tissue by peroxidase-conjugated antibody method: light and electron microscopic studies.

Hepatitis A antigen (HAAG) was localized in liver tissue from marmosets inoculated with human hepatitis A virus (HAV) by light and electron microscopy by using a peroxidase-conjugated antibody method. The fine granular peroxidase staining was scattered throughout the cytoplasm of liver cells when viewed with the light microscope. The distribution of HAAg-positive cells was focal. Virus-like particles, 24 to 27 nm in diameter, were observed in the cytoplasm of hepatocytes and smaller cells, resembling Kupffer cells, by standard thin-section electron microscopy (thin section EM). By immunoperoxidase electron microscopy (immunoperoxidase EM), HAAg was detected on the particles, which were aggregated within cytoplasmic vesicles of the hepatocyte. The surrounding membrane of the vesicles was also HAAg- positive. Similar HAAg particles were observed in the cytoplasm of smaller cells adjacent to hepatocytes as well. Thus, immunoperoxidase EM revealed that the 24- to 27-nm virus-like particles in the cytoplasm of liver cells obtained from marmosets were infected with HAV contained HAAg.     

Isolation and Amino Acid Analysis of Mallory Bodies

Mallory bodies were isolated from the livers of alcoholic patients obtained at autopsy. The liver tissue was homogenized by a pressure homoge-nizer using nitrogen gas in excess of 2, 000 p. s. i. Solutions of 65% and 70% sucrose were used for discontinuous gradient ultracentrifugation. A distinct band between the two sucrose layers was collected, which was rich in Mallory bodies. Purity of the Mallory body fraction was examined by light and electron microscopy. Mallory body fractions were analyzed for amino acid composition.     

Severity of alcohol dependence in patients with alcoholic liver disease.

To determine the severity of dependence on alcohol in patients with alcoholic liver disease the severity of alcohol dependence questionnaire was administered to 193 patients with various types of alcoholic liver disease established histologically, in whom a detailed history of lifetime alcohol consumption was also obtained. Only 34 patients (18%) were classified as being severely dependent compared with 56% of patients without overt liver disease who were attending a neighbouring alcohol treatment unit. There was a significant correlation between the severity of dependence and mean daily alcohol consumption (r = 0.45 and 0.39 for men and women, respectively) but not duration of drinking. Dependence scores tended to be lower in patients with cirrhosis than in those with precirrhotic liver disease, but this difference reached significance only in women. These findings confirm that patients who develop chronic alcoholic liver disease are usually only mildly dependent on alcohol and support the hypothesis that patients who escape florid symptoms of alcohol dependence are at greater risk of developing liver damage because they are able to sustain a continual consumption of alcohol over many years.     

Ultrastructural study of human glomerular capillary loops with IgA nephropathy using quick-freezing and deep-etching method

Immunoglobulin A (IgA) nephropathy shows great variability regarding the histological features of the lesions of human renal glomeruli. In the present study, the quick-freezing and deep-etching (QF-DE) method was used to analyze the glomerular ultrastructure of biopsied kidney tissues from children with IgA nephropathy. Biopsied renal tissues were routinely prepared for light microscopy, immunofluorescence microscopy, conventional electron microscopy, and replica electron microscopy. The three-dimensional ultrastructure of glomeruli of the kidney was clearly observed by using the QF-DE method. Three layers of glomerular basement membranes, i.e., middle, inner and outer layers, were clearly detected in the replica electron micrographs. The middle layer was 343.0+/-24.2 nm (n=20) in width and formed polygonal meshwork structures. We also observed slit diaphragms, electron-dense mesangial deposits, and increased amounts of mesangial matrix and foot process effacement. Many delicate filaments were found to be distributed from the apical to the bottom portions between neighboring foot processes. The ultrastructural difference between the replica electron micrographs and conventional electron micrographs was found to be especially marked in the appearance of foot processes and connecting filaments between the neighboring foot processes. The examination of extracellular matrix changes, as revealed at high resolution by the QF-DE method, gave us some morphofunctional information relevant to the mechanism of proteinuria with IgA nephropathy.     

Altered Hepatic Transport by Fetal Arsenite Exposure in Diet‐Induced Fatty Liver Disease

Non‐alcoholic fatty liver disease can result in changes to drug metabolism and disposition potentiating adverse drug reactions. Furthermore, arsenite exposure during development compounds the severity of diet‐induced fatty liver disease. This study examines the effects of arsenite potentiated diet‐induced fatty liver disease on hepatic transport in male mice. Changes were detected for Mrp2/3/4 hepatic transporter gene expression as well as for Oatp1a4/2b1/1b2. Plasma concentrations of Mrp and Oatp substrates were increased in arsenic exposure groups compared with diet‐only controls. In addition, murine embryonic hepatocytes and adult primary hepatocytes show significantly altered transporter expression after exposure to arsenite alone: a previously unreported phenomenon. These data indicate that developmental exposure to arsenite leads to changes in hepatic transport which could increase the risk for ADRs during fatty liver disease.     

Histopathological effects of cisplatin,doxorubicin and 5-flurouracil (5-FU) on the liver of male albino rats

Cisplatin, doxorubicin and fluorouracil (5-FU), drugs belonging to different chemical classes, have been extensively used for chemotherapy of various cancers. Despite extensive investigations into their hepatotoxicity, there is very limited information on their effects on the structure and ultra-structure of liver cells in vivo. Here, we demonstrate for the first time, the effects of these three anticancer drugs on rat liver toxicity using both light and electron microscopy. Light microscopic observations revealed that higher doses of cisplatin and doxorubicin caused massive hepatotoxicity compared to 5-FU treatment, including dissolution of hepatic cords, focal inflammation and necrotic tissues. Interestingly, low doses also exhibited abnormal changes, including periportal fibrosis, degeneration of hepatic cords and increased apoptosis. These changes were confirmed at ultrastructural level, including vesiculated rough endoplasmic reticulum and atrophied mitochondria with ill-differentiated cisternae, dense collection of macrophages and lymphocytes as well as fibrocytes with collagenous fibrils manifesting early sign of fibrosis, especially in response to cisplatin and doxorubicin -treatment. Our results provide in vivo evidence, at ultrastructural level, of direct hepatotoxicity caused by cisplatin, doxorubicin and 5-FU at both light and electron microscopi. These results can guide the design of appropriate treatment regimen to reduce the hepatotoxic effects of these anticancer drugs.     

Isolation and characterization of nuclei from rice embryos.

A method has been developed to isolate pure preparations of nuclei in high yield from commercially available viable rice embryos (germ), employing extraction with buffer solution containing glycerol (without detergent) and polyamine, followed by centrifugation on a 30% Percoll cushion. The intactness of the isolated nuclei was confirmed by light microscopy as well as electron microscopy. The protein profiles of both whole nuclei and nuclear extracts obtained by SDS-PAGE, organellar marker enzyme activities, DNA and RNA analyses, and in vitro RNA synthesis, all indicate that the highly purified nuclei are isolated from rice embryos.     

Ultrastructural zonal heterogeneity of hepatocytes and mitochondria within the hepatic acinus during liver regeneration after partial hepatectomy

BACKGROUND INFORMATION: Partial hepatectomy (70%) induces cell proliferation until the original mass of the liver is restored. In the first 24 h after partial hepatectomy, drastic changes in the metabolism of the remaining liver have been shown to occur. To evaluate changes in hepatocyte ultrastructure within the hepatic acinus during the liver regenerative process, we investigated, by light and electron microscopy observations on specimens taken 0 h, 24 h and 96 h after partial hepatectomy, the hepatocyte structure and ultrastructure in the periportal and pericentral area of the hepatic acinus, with a particular emphasis on mitochondria ultrastructure. Moreover, some biochemical events that could affect the mitochondria ultrastructure and function were investigated. RESULTS: We found that, 24 h after partial hepatectomy, mitochondria with altered ultrastructure were preferentially localized in the periportal area. Periportal hepatocytes showed also an increase in the number of peroxisomes, free ribosomes, lysosomes and autophagosomes. Altered mitochondria showed swelling, an ultrastructural index of increased membrane permeability, a reduction in the number of cristae, and a rarefied, often vacuoled, matrix. Consistently, an increase in the mitochondrial oxidized/reduced glutathione ratio was found as well as calcium release from mitochondria in a manner inhibited by cyclosporin A. Interestingly, light and electron microscopy analysis showed that the hepatocytes in the periportal area were the cells with the major structural attributes to proliferate. At 96 h after partial hepatectomy, the preferential zonation of altered mitochondria was lost and the normal mitochondrial membrane permeability properties were restored. CONCLUSIONS: We suggest that 24 h after partial hepatectomy, a preferential zonation of altered mitochondria in the periportal hepatocytes could be involved in the changes of metabolic and functional heterogeneity of the hepatocytes within the hepatic acinus during the regenerative process.     

Structural and Ultrastructural Characteristics of Bone-Tendon Junction of the Calcaneal Tendon of Adult and Elderly Wistar Rats

Tendons are transition tissues that transfer the contractile forces generated by the muscles to the bones, allowing movement. The region where the tendon attaches to the bone is called bone-tendon junction or enthesis and may be classified as fibrous or fibrocartilaginous. This study aims to analyze the collagen fibers and the cells present in the bone-tendon junction using light microscopy and ultrastructural techniques as scanning electron microscopy and transmission electron microscopy. Forty male Wistar rats were used in the experiment, being 20 adult rats at 4 months-old and 20 elderly rats at 20 months-old. The hind limbs of the rats were removed, dissected and prepared to light microscopy, transmission electron microscopy and scanning electron microscopy. The aging process showed changes in the collagen fibrils, with a predominance of type III fibers in the elderly group, in addition to a decrease in the amount of the fibrocartilage cells, fewer and shorter cytoplasmic processes and a decreased synthetic capacity due to degradation of the organelles involved in synthesis.     

非酒精性脂肪肝病肝组织超微结构特点

目的:阐明非酒精性脂肪肝病(NAFLD)的超微结构特点。方法:收集我校和其他单位送检的3例单纯性非酒精性脂肪肝,16例NASH患者和4例NAFLD肝硬化患者的肝穿刺组织。用2.5%戊二醛、1%锇酸双固定、Epon 812包埋,超薄切片70nm,醋酸铀和柠檬酸铅染色后,JEM-2000EX透射电镜观察。结果:单纯性脂肪肝患者主要表现为大小不等的脂滴沉积、以小脂滴为主,可互相融合。NASH患者的肝细胞都可出现大量脂滴积聚,为大小脂滴混合型、内容物主要为中等电子密度、比较均一的甘油三酯,部分脂滴周围可见磷脂成分,NASH患者肝细胞内脂滴也互相融合。肝细胞线粒体的超微结构改变包括多形性线粒体、基质颗粒增多、线粒体增大和嵴的丧失是主要的电镜异常发现,线粒体内还可见副晶格样包涵体。部分NASH患者肝细胞内可见Mallory小体。NASH患者肝细胞周围可见淋巴细胞浸润。肝血窦Kupffer细胞增生不明显,NAFLD肝硬化患者Disse间隙和肝细胞间可见胶原纤维增生。结论:NAFLD具有较为明确的超微结构改变,电镜检查有助于诊断。     

Optimization of a histopathological biomarker for sphingomyelin accumulation in acid sphingomyelinase deficiency

Niemann-Pick disease (types A and B), or acid sphingomyelinase deficiency, is an inherited deficiency of acid sphingomyelinase, resulting in intralysosomal accumulation of sphingomyelin in cells throughout the body, particularly within those of the reticuloendothelial system. These cellular changes result in hepatosplenomegaly and pulmonary infiltrates in humans. A knockout mouse model mimics many elements of human ASMD and is useful for studying disease histopathology. However, traditional formalin-fixation and paraffin embedding of ASMD tissues dissolves sphingomyelin, resulting in tissues with a foamy cell appearance, making quantitative analysis of the substrate difficult. To optimize substrate fixation and staining, a modified osmium tetroxide and potassium dichromate postfixation method was developed to preserve sphingomyelin in epon-araldite embedded tissue and pulmonary cytology specimens. After processing, semi-thin sections were incubated with tannic acid solution followed by staining with toluidine blue/borax. This modified method provides excellent preservation and staining contrast of sphingomyelin with other cell structures. The resulting high-resolution light microscopy sections permit digital quantification of sphingomyelin in light microscopic fields. A lysenin affinity stain for sphingomyelin was also developed for use on these semi-thin epon sections. Finally, ultrathin serial sections can be cut from these same tissue blocks and stained for ultrastructural examination by electron microscopy.     

Immunocytochemical localization of progesterone-binding protein (PBP) in guinea-pig placental tissue

Summary The cellular localization of progesterone-binding protein (PBP) in the guinea-pig placenta was studied by use of immunocytochemical procedures. Within the chorioallantoic placenta, a strong positive reaction was observed in the interlobar and marginal trophoblast from the third week of gestation to term. PBP was localized in the cytoplasm of the syncytiotrophoblast, and the nuclei were never stained. At the ultrastructural level, the immunoreaction was associated with the rough endoplasmic reticulum, the Golgi apparatus and the perinuclear space. No deposits were seen in any other cell organelles. This localization strongly suggests that the interlobar syncytium is related to PBP synthesis. In the labyrinth, a weak immunoreaction was observed by light microscopy around some blood lacunae. At the ultrastructural level the dense deposits were localized in vesicles located near the maternal lacunae.The distribution of PBP was also studied by light microscopy in other tissues from pregnant guinea-pig. No PBP, or PBP-like material, was detected inside cells from liver, muscle, heart, lung, kidney, ovary, and uterus. A weak immunoreaction for PBP was detected in vascularized zones of these organs.These observations strongly suggest that PBP, a protein related to gestation in the guinea-pig, is elaborated by the placental tissue of this hystricomorph rodent. PBP is the first steroid-binding plasma protein shown to be of extrahepatic origin.     

Histopathological biomarkers and genotoxicity in gill and liver tissues of Nile tilapia Oreochromis niloticus from a polluted part of the Nile River,Egypt

Fish health is affected by water pollution. Oreochromis niloticus collected during summer 2014 from El-Serw, a polluted site on the Nile River, were compared with fish from a reference site, El-Zamalek. Histopathological changes were detected in gill and liver tissue samples using light and electron microscopy. In addition, the degree of DNA damage was measured using the comet assay. To indicate the severity of water pollution at the two sites, physico-chemical properties and heavy metal concentrations were investigated. Gill damage, including lamellar cell hyperplasia and aneurysm, was observed in the fish samples from the polluted site. The livers of fish from the polluted area showed necrosis and an increase in melanomacrophage centres. Histochemical results confirmed a marked rise of gill mucopolysaccharides and a reduction of carbohydrate stored in hepatocytes. Electron microscopy revealed clear alterations in gill and liver tissue of fish from the polluted site. The comet assay showed highly significant DNA damage in tilapia collected from the polluted site, compared to those from the reference site. Histopathological biomarkers and the comet assay may therefore be sensitive indicators of exposure to mixtures of aquatic pollutants in Nile tilapia.     

Morphological changes during conoid extrusion in Toxoplasma gondii tachyzoites treated with calcium ionophore

Treatment of tachyzoites of Toxoplasma gondii with the calcium ionophore A23187 induced dramatic ultrastructural changes that were observed by light and electron microscopy. Light microscopy showed a higher percentage (22%) of tachyzoites with the conoid extruded when compared to control parasites. Electron microscopy confirmed the conoid extrusion by both transmission and scanning electron microscopy. Freeze-fracture replicas showed that the plasma membrane adjacent to cytoplasmic dense granules appeared devoid of intramembranous particles. Membrane-limited vesicles and filopodium-like structures at the cell surface were observed in treated cells. 3-D reconstruction from serial sections confirmed the data and showed a heterogeneity in dense granule shape not reported in control cells.