Circular Cristae Research Articles

Ultrastructural characteristics of primary renal epithelial tumours with granular oncocytic cytoplasm

Background/Aim. Ultrastructural analysis of tumours has shown many common characteristics of certain neoplasms, as well as their specificities. Primary renal epithelial tumours with granular oncocytic cytoplasm is a very heterogeneous group in their histological origin and biological behaviour, which results in a difference in treatment and prognosis of the disease, making accurate morphological diagnosis necessary. The aim of this study was to determine ultrastructural similarities and differences among primary renal epithelial tumours with granular oncocytic cytoplasm. Methods. The analysis of archival and routine material in the archives of the Department of Pathology, University Hospital in Plzen, Czech Republic, as well as archival and routine material in the Centre for Pathology and Histology, Clinical Centre of Vojvodina in Novi Sad, discovered 346 primary renal epithelial tumours with granular oncocytic cytoplasm and divided them into 5 groups: 1) renal oncocytoma (RO) (234 tumours), 2) oncocytic papillary renal cell carcinoma (OPRCC) (12 tumours), 3. sporadic renal hybrid oncocytic/ chromophobe tumour (HOCT) without evidence of Birt Hogg Dub? syndrome (BHD) (14 tumours), 4) chromophobe renal cell carcinoma (ChRCC) (21 tumours) and 5) granular renal cell carcinoma (RCC) [64 tumours + 1 clear cell RCC (CRCC) with hyaline globules]. Ultrastructural analysis of tumour cells at the subcellular level was done using electron microscope (Philips electron microscope TEM 208) at the Department of Pathology, University Hospital in Plzen, Czech Republic. Cellular organelles and pigments were evaluated in 5 tumours from each group according to the simple random sample principle with a total of 30 analysed tumours. Results. In all analysed primary renal epithelial tumours with granular oncocytic, cytoplasm dominant organelles were mitochondria. Specific ultrastructural characteristics of RO were round mitochondria with lamellar cristae, whereas ChRCC had numerous typical cytoplasmic microvesicles 100?700 nm large and mitochondria with tubulovesicular, lamellar and circular cristae. Ultrastructural specificity of hybrid tumours were rare microvesicles and numerous mitochondria of O-PRCC mitochondria with lamellar cristae and small intracytoplasmic vesicles, 100?200 nm large, and of granular RCC, in addition to mitochondria, also glassy hyaline globules (GHG). Conclusion. Ultrastructural analysis indicates mitochondria as the dominant organelle in the analysed tumours. Electron microscopy showed specificities, i.e., differences in appearance of cristae, presence and size of vesicles as well as deposition of pigment in and out of cytoplasm and glassy hyaline globules.

Bee (Apis mellifera) Venom Produced Toxic Effects of Higher Amplitude in Rat Thoracic Aorta than in Skeletal Muscle—An Ultrastructural Study

In this study, changes produced in aorta and triceps surae muscle of Wistar rats as response to bee venom (BV) envenomation were analyzed by transmission electron microscopy and morphometry. A subchronic treatment of 30 days with daily doses of 700 μg BV/kg and an acute-lethal treatment with a single dose of 62 mg BV/kg were performed. The subchronic treatment resulted in endothelial cell retraction, a thicker subendothelial layer, and thinner elastic laminae and musculoelastic layers in aorta, and thicker endothelium and basal laminae in skeletal muscle. In both tissues polymorphous, swollen mitochondria with disrupted cristae were observed. The acute treatment produced extensive endothelial lesions, breakdown of the collagen layer and migration of muscle cells toward the intima in the aorta, and dilatation of endoplasmic reticulum in the skeletal muscle cells. Mitochondria were almost devoid of cristae or with few circular cristae in the smooth muscle cells while most of the mitochondria presented abnormal circular cristae in the skeletal muscle cells. Degenerative alterations in the aorta were of higher intensity in our experiments-both the intima and media strongly responded to BV, in contrast to those found at the level of the skeletal muscle cells where a moderate degenerative myopathy was recorded.

G.P.19.03 Working under stress: Premature aging of paravertebral muscles

Intervertebral disc disease and instabilities of the vertebral column result in painful conditions with or without neurological deficits. After informed consent paravertebral muscle specimens were taken during surgery from 37 patients with disc protrusion and 26 patients with spondylolisthesis. Although myopathy related symptoms were absent, all biopsies showed alterations ranging from mild to severe. Neurogenic atrophy was present in almost half of the patients in both groups. Ragged red fibers were detected in 8 cases (21%) of the disc protrusion group and in 21 cases (80%) of the spondylolisthesis group. Intrasarcoplasmatic lipid and glycogen accumulation as indicators of an impaired mitochondrial function was frequently observed and appeared associated with mitochondrial accumulation. At the ultrastructural level the numerical increase of mitochondria was confirmed. They showed different configurational abnormalities as circular cristae and paracristalline inclusions. Another frequent finding was intrasarcoplasmatic lipofuscin pigment accumulation which was noticed even in young patients. It can be assumed that a premature aging of the muscle may result from inappropriate chronic stress due to pain and/or contractions. This may induce mitochondrial pathology similar to the classic mitochondriopathies as well as mitochondrial alterations found in senescence. In contrast to mtDNA mutations which are responsible for the above mentioned conditions, the pathological findings in this series are supposed to be secondary to local distress.

Chromophobe renal cell carcinoma with microcystic and adenomatous arrangement and pigmentation—a diagnostic pitfall. Morphological, immunohistochemical, ultrastructural and molecular genetic report of 20 cases

We present clinical, morphological, immunohistochemical, ultrastructural and molecular genetic features of 20 cases of a peculiar form of chromophobe renal cell carcinoma (CRCC) with morphology differing from that of conventional CRCC. Microscopically, the typical features of the tumors were microcystic arrangement and formation of adenomatous structures. Microcystic areas were composed of smaller eosinophilic and bigger pale cells having cytological appearance typical of conventional CRCC. Cytological features of the adenomatous structures were mostly different from those of conventional CRCC. They had a typical columnar arrangement with nuclei positioned at the base of the glandular structures and a small amount of a deeply eosinophilic cytoplasm often endowed with brush border facing the lumen of the glands. In addition, all the tumors showed a brown pigmentation. The pigmentation was located mostly extracellularly, where it formed pools of heavy deposits. Microscopic calcifications present in all cases formed psammoma bodies or else the calcifications were more extensive and amorphous in shape. Ultrastructurally, the cells showed features characteristic of CRCC: typical cytoplasmic vesicles were 100-700 nm in size and mitochondria had tubulovesicular, lamellar or circular cristae. Some tumor cells contained dark, variously sized electron-dense pigment granules. Neither melanosomes nor membrane-bound neurosecretory granules were seen. Using fluorescence in-situ hybridization probes for chromosomes 1, 2, 6, 10, 13, 17 and 21, the tumors revealed massive loss of tested chromosomes typical for conventional CRCC. Monosomy of chromosomes 1, 2, 6, 10, 13 and 21 was found in 100, 36, 91, 82, 82, 82 and 64% of cases, respectively. None of the cases showed mutation of exons 9, 11, 13 and 17 of the c-kit gene. The important feature of pigmented microcystic chromophobe renal cell carcinoma is a relatively benign biological behavior and the absence of distant metastases and sarcomatoid transformation.

Mitochondria in activated microglia in vitro

In the CNS, microglia become activated, i.e. change their functional state and phenotype, in response to a wide variety of pathological stimuli. Since this activation is triggered at a very low threshold and at the same time remains territorially restricted, the spatial distribution of activated microglia can be used as a sensitive, generic measure of the anatomical localisation of ongoing disease processes. One protein complex, undetectable in resting microglia but highly up-regulated upon activation in vivo and in vitro, is the 'peripheral benzodiazepine binding site', as measured by binding of the isoquinoline derivate PK11195. Particularly numerous in the outer membrane of mitochondria, this binding site has also been referred to as the 'mitochondrial benzodiazepine receptor'. The de novo expression of this receptor by activated microglia suggests that the process of activation may be associated with important qualitative changes in the state of mitochondria. Here, we provide confocal light- and electron microscopic evidence that the activation of microglia indeed entails conspicuous mitochondrial alterations. In cultured rat microglia stained with the fluorescent probe, JC-1, a sensitive indicator of mitochondrial membrane potential, we demonstrate that stimulation by bacterial lipopolysaccharide and interferon-gamma increases the number of microglial mitochondrial profiles and leads to marked changes in their morphology. Prominent elongated, "needle-like" mitochondria are a characteristic feature of activated microglia in vitro. Electron microscopically, an abundance of abnormal profiles, including circular cristae or ring- and U-shaped membranes, are found. Our observations support the notion that the previously reported increase in microglial binding of PK11195, that labelled with carbon-11 ([11C] (R)-PK11195) has clinical use for the visualisation of activated microglia in vivo by positron emission tomography, may at least in part relate to an increased number and altered functional state of microglial mitochondria.

Ocular Pathology of MELAS Syndrome with Mitochondrial DNA Nucleotide 3243 Point Mutation

The authors describe the clinical, histopathologic, and ultrastructural findings in two eyes obtained at autopsy from a 21-year-old woman with mitochondrial encephalomyopathy, lactic acidosis, and stroke-like episodes (MELAS syndrome). The eyes were obtained immediately after death. The right eye was fixed in 10% neutral-buffered formalin and processed for standard histologic examination. The left eye was fixed in a neutral-buffered 2.5% glutaraldehyde solution and processed for transmission electron microscopic examination. The authors compared the histologic and ultrastructural findings with the clinical features recorded photographically. The main clinical ophthalmologic features were bilateral ptosis, chronic external ophthalmoplegia, diffuse choroidal atrophy, atypical pigmentary retinopathy with macular involvement, and patchy atrophy of the iris stroma. Molecular genetic analysis detected a tRNA Leu (UUR) point mutation at position 3243 of mitochondrial DNA (MELAS genotype). Results of histologic and ultrastructural examination showed ragged-red fibers in the rectus muscles, degeneration of photoreceptor outer segments in the macula, hyperpigmentation and atrophy of the retinal pigment epithelium of the macula, atrophy of the iris stroma, early posterior subcapsular cataract, and optic atrophy. The retinal pigment epithelium, inner segments of the photoreceptors, smooth muscle cells of the choroidal and retinal vessels, the dilator and sphincter muscle of the iris, cornea, lens epithelium, and ciliary epithelium all contained many, often enlarged, structurally abnormal mitochondria with occasional paracrystalline inclusions and circular cristae. The MELAS-associated mitochondrial DNA nucleotide 3243 point mutation can cause a spectrum of ocular signs and symptoms that may be dependent on the patient's age and the amount of mutant mitochondrial DNA in the tissue. MELAS syndrome should be considered in the differential diagnosis of bilateral ptosis, external ophthalmoplegia, and atypical pigmentary retinopathy with macular involvement.

Adrenal Cortical Adenoma in the Spinal Canal of an 8-Year-Old Girl

An ectopic adrenal cortical adenoma containing high levels of androstenedione but without clinically detectable virilizing effects was found in the spinal intradural space of an 8-year-old girl. The tumor, which was located at the L2 level, manifested itself clinically by a short history of bilateral leg pain. It was well encapsulated; therefore, total surgical removal was accomplished. The light microscopic appearance of the tumor was typical of adenomatous adrenal cortical tissue. Ultrastructurally, it also showed characteristic features of steroid-producing tumors, including very abundant smooth endoplasmic reticulum and giant mitochondria with tubulovesicular and circular cristae. Frozen tissue analyzed by radioimmunoassay was found to contain almost 20 times the normal tissue level of androstenedione. There was no elevation of cortisol or aldosterone levels in the tumor. Postoperative magnetic resonance imaging (MRI) scan of the retroperitoneum showed no abnormalities in the patient's adrenal glands. Serum androstenedione levels were normal. We postulate that the adenoma developed from congenital ectopic rests of intraspinal adrenal tissue. Although ectopic occurrence of adrenal cortical tissue has been recorded in other areas, neither such rests nor tumors developing from them have been previously reported within the spinal canal.

Studies on the ultrastructure, virus-like particles and infectivity of Leishmania hertigi.

Five strains of Leishmania hertigi hertigi isolated in Panama and three strains of L. hertigi deanei isolated in Brazil were studied. Ultrastructural examination of promastigotes grown in culture showed virus-like particles (VLPs), 55--60 nm diameter, in the cytoplasm of all strains. The VLPs were normally either organized in paracrystalline clusters or associated with induced tubules. In some cases the VLPs were associated with dense vesicular bodies. Mitochondria with which the VLPs were associated had enlarged elongate or circular cristae. Elongate 'microbodies' containing rod-like structures were observed in promastigotes grown in culture. Poor infections of promastigotes developed in the midguts of 10% of laboratory-bred Lu. longipalpis following experimental feeding on cultures of L. h. hertigi. VLPs were seen in a promastigote in the midgut of a sandfly five days after feeding. Laboratory mammals proved poor hosts for L. hertigi. Cryptic infections in the visceral organs of immunosuppressed hamsters and immunodeficient 'nude' mice were detectable only by culture. Infections of DS cell and mouse peritoneal macrophage cultures showed amastigotes with a high ribosomal density and deep invaginations of the pellicular layer. VLPs were rarely seen in these amastigotes.

A tissue culture study of the toxic effect of vincristine on skeletal muscle

Well-differentiated cultures of mouse skeletal muscle exposed to various concentrations of vincristine sulfate were examined at different time intervals by light and electron microscopy. At higher concentrations of vincristine (1, 2 m m) for 1 day, skeletal muscle showed spheromembranous degeneration. Degenerated muscle fibers contained hyalinized myofilaments, whorl formation of rough endoplasmic reticulum, swollen mitochondria with circular cristae, many myelin figures, and dense bodies. At lower concentrations (0.01, 0.1 m m) for 3 days, the muscle fibers showed less severe degeneration and contained many crystalline inclusions in the sarcoplasm. This study suggests that vincristine produces, in differentiated ske'etal muscle cultures, crystalline inclusions as well as spheromembranous degeneration.

中枢性鎮痛薬の依存性に関する研究（第5報）

Influence of morphine on the fine structure of mitochondria in the cells of zona fasciculata of the adrenal cortex in mice in which a morphine pellet was subcutaneously implanted was studied using electron microscope. (1) Transformation of the mitochondrial structure, i.e. swelling, formation of lamellar or concentric circular cristae and decrease of electron density of the mitochondrial matrix, was observed 12 hr after implantation, and changes reached a maximum state at 48 hr. These transformations, however, disappeared wihtin 4 days. (2) On the 4th day after implantation, removal the pellet again produced transformation of the mitochondria with withdrawal symptoms, and a normal state was reverted to 72 hr later. Levallorphan challenge produced similar changes. (3) Injection of morphine into mice after removal of the pellet prevented the appearance of mitochondrial transformation. From the results obtained it may be concluded that there are correlations between the transformation of the mitochondria and physical dependence on morphine in mice.

Ultrastructural Aspects of Primary Biliary Cirrhosis and Other Types of Cholestatic Liver Disease

Seven patients with primary biliary cirrhosis were studied clinically, biochemically, and by light and electron microscopy. Serial liver biopsies were examined. The electron-microscopic findings were compared with those in 5 patients with extrahepatic obstructive jaundice, 3 with cholestatic viral hepatitis, 2 with chronic aggressive hepatitis, and 2 with other types of cirrhosis. Distinctive features were observed in patients with primary biliary cirrhosis in the small and medium-sized bile ducts. These consisted of the following: the bile duct epithelium shows intracytoplasmic filamentous structures grouped into bundles which become progressively more abundant and prominent. The mitochondria are swollen and exhibit fewer circular cristae. The cytoplasm in addition is occupied by numerous cytophagosomes which decrease with progression of disease. The rough endoplasmic reticulum is vesicular and ribosomes are scanty. The luminal microvilli are at first blunted and scanty and finally disappear. In the final stage, the basement membranes of the bile ducts are disrupted and invaded by polymorphonuclear leukocytes. Changes were observed in hepatocytes as well. At the early stage they contain numerous cytophagosomes, and the mitochondria show homogenization of their matrix with curling and disappearance of cristae, granules, and prominent crystalline inclusions. These findings vary with progression of disease and do not appear to be characteristic. Evidence from the literature supporting this interpretation is discussed. Some of the changes observed in the bile ducts are also seen to a minor degree in other pathological entities, but their prominence and progression are distinctive in primary biliary cirrhosis and possibly make them features of diagnostic significance. However, comparative studies of larger series are necessary in order to assess the significance of the findings reported here.

Ultrastructural study of the anomalous cell wall in Rhodotorula gracilis.

Cells ofRhodotorula gracilis form under certain conditions equatorial rings, visible in the UV-fluorescence microscope after staining with a CFW brightener. The ultrastructural studies showed that the above rings are formed by a centripetal thickening of the cell wall. Mitochondria with circular cristae and anomalous, ring-like mitochondria were observed in cytoplasm of the cells with developed rings.

Electron microscopic and enzyme histochemical studies of cerebellum, ocular and skeletal muscles in chronic progressive ophthalmoplegia with cerebellar ataxia.

Electron microscopic and enzyme histochemical studies were performed on the cerebellum and the ocular and deltoid muscles from a 38 year old woman who developed bilateral ptosis at the age of nine years. Histologically the cerebellum appeared normal. The biopsies of three ocular muscles showed varying sizes of muscle fibers which were rounded and contained increased numbers of subsarcolemmal nuclei. The deltoid muscle stained by hematoxylin and eosin appeared normal, but the trichrome stain showed increased numbers of red granules within the sarcolemma corresponding ultrastructurally to increased numbers of abnormal mitochondria. These abnormal mitochondria displayed increased reaction products with LDH, NADH and SDH preparations, while the muscle gave normal reaction in phosphorylase, PAS and myosin ATP preparations. Chemical studies on the cerebellum showed normal proteolipids, glycolipids and phospholipids. Ultrastructurally, the cerebellum, the myofibers of three ocular muscles and the deltoid muscle exhibited abnormal mitochondria which showed peculiarly arranged circular cristae. They frequently contained paracrystalline structures which consisted of individual tubules arranged in a helical pattern. Frequently, the abnormal mitochondria were replaced by dense rectangular inclusions and occasionally showed complete transition to crystalline structures.

Nutritional cirrhosis in rhesus monkeys: Electron microscopy and histochemistry

A choline-deficient low protein diet was fed to twelve Rhesus monkeys for two years. Eight of the animals died, most of them during the latter part of the first year. Mortality among males was higher than in females. Three of the four surviving animals developed fatty metamorphosis followed by cirrhosis. Eight sequential liver biopsies from each of these animals were studied. Control specimens showed paracrystalline mitochondrial inclusions in the hepatocytes and cytoplasmic crystalloids in the endothelial cells of the hepatic sinusoids and portal vessels. The significance of both structures remains unknown. Striking cytoplasmic vacuoles, possibly produced by anoxia during surgical liver biopsy, were observed in some specimens. The hepatocytes of the animals on the experimental diet, in addition to fatty change, showed mitochondria with bizarre shapes, circular cristae or increased electron opacity. Focal cytoplasmic degradation and Golgi dilatation were prominent. Microvilli developed along the intercellular spaces and became more prominent in the space of Disse. Basement membranes which were rarely continuous could be seen between hepatocytes and sinusoidal lining cells. In Disse spaces and intercellular spaces microfibrils and increased collagen fibers developed. In the later biopsies septa were formed which contained a higher proportion of typical collagen to microfibrils than the fibrillar material in the Disse spaces. The hepatocytes in the cirrhotic nodules stained more strongly for glycogen and were more active in nearly all histochemical enzyme reactions than the hepatocytes in non-nodular areas. This suggests that the nodules differed metabolically from the rest of the parenchyma.