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PubMedDate not supplied

[Juvenile granulosa-cell tumor of the ovary. Immunohistochemical and ultrastructural study].

In 1977 Scully first described the juvenile granulosa cell tumor of the ovary (JGCT) as a special variation of the granulosa cells tumor, which occurs in the two first decades of life, and 97% of the cases show characteristic microscopic and histological features. Five previous cases have been reported concerning the ultramicroscopic characteristics of this ovarian neoplasia. The purpose of this paper is to report the immunohistochemical and ultrastructural characteristics in a case of OJCGT which occurred in a four year old girl with isosexual precocious pseudopuberty. The presence of vimentin and absence of keratin was proven immunohistochemically in this ovarian neoplasia. Intermediate filaments were found ultrastructurally. The combined use of immunohistochemical and ultrastructural techniques has proven to be of extraordinary usefulness for the differential diagnosis between epithelial and non epithelial ovarian tumors and adds a new and highly specific method to characterize and differentiate the cells of embryonic carcinoma, choriocarcinomas and endodermal sinus tumors which are keratin positive.

Biomarkers, Tumor↗
PubMed2006

[Protection of extract from Cuscuta japonica on human sperm acrosome and ultrastructure].

OBJECTIVE: To study the oxidation damage of active oxygen (ROS) to human sperm acrosome and ultrastructure, and study the function mechanism about Cuscuta japonica treating male's infertility and asthenoospermia. METHOD: By using the Percoll gradient centrifugation, the sperm with normal physiological function were selected for the normal sperm model, and the sperm suspension were divided into the normal group, the model group, the positive control group (Vitamin C group), and the lugh, the median and the low dose gvoups of C. japonica. The ROS made from hypoxanthine-xanzine xanzine(HX-XO) and different content (0.125, 0.25, 0.5 g x mL(-1)) of extract were incubated with sperm in the oxygen environment. The acrosomic integrity rate were calculated and the sperm acrosome and ultrastructure were observed. RESULT: The content (0.125, 0.5 g x mL(-1)) of extract had no obvious difference as compared with Vitamin C (0.25 mg x mL(-1)) in protecting the acrosome and ultrastructure, but the content (0.25 mg x mL(-1)) of extract was significantly better than Vit C (P < 0.001). CONCLUSION: The suitable content of extract from C. japonica can significantly protect the sperm membrane, the acosomic structure and the mitochondrion function from the damage caused by ROS.

Acrosome↗
PubMed2004

Ultrastructure of the central nervous system: the basics.

Since the articles in this supplement describe ultrastructural changes in diseases of the nervous system, for better understanding of these papers dealing with pathology of the this system, basic elements of the ultrastructure of the central nervous system are presented in this survey. Description of the fine structure of cells and fibres of the central nervous system presented below is based on classical textbooks as well as on the authors' personal experience. The details of ultrastructure of nerve cells (their nucleus and cytoplasm, including cell organelles: abundant granular endoplasmic reticulum, prominent Golgi apparatus, mitochondria, lysosomes, as well as other cell components including: neurofilaments, lipid droplets, multivesicular bodies, lipid droplets, lipofuscin granules, and in some cells melanin granules, and also cell processes), the interneuronal chemical synapses (specialized site of interneuronal communication) as well as all types of neuroglial cells (a class of non-neuronal supporting cells): astrocytes (fibrous and protoplasmic), oligodendrocytes, and microglia neuroglial cells are described.

Animals↗
PubMed2006

[The features of four types of operation for treating chronic hypertrophy rhinitis and ultrastructure observation of the inferior turbinate mucosa].

OBJECTIVE: To assess the features of four types of operation for treating chronic hypertrophy rhinitis and to observe the ultrastructure of inferior turbinate mucosa. METHOD: Eighty-eight cases of chronic hypertrophic rhinitis (HR) were treated by transnasal endoscopic submucous inferior turbinate resection (group A), thirty cases of HR were treated by partial inferior turbinectomy (group B), thirty six cases of HR were treated by bipolar radiofrequency ablation on inferior turbinate (group C), ten cases of HR were treated by injection of sclerosing agent (group D). The efficacy in the three groups (A,B,C) and the features of four types operation were compared and the ultrastructure of inferior turbinate was observed both preoperatively and postoperatively. RESULT: Four groups of HR were followed up 4 months to half year after operation, effective rate was 97.4 (group A) 100% (group B) and 93.4% (group C) respectively, while group A, group B and group C effective rate had no significant difference among them. Group A and group C have more advantages compared to the other 2 groups for they remained good ultrastructure of inferior turbinate mucosal cilia after 4 to 6 months postoperatively. CONCLUSIONS: The use of transnasal endoscopic submucous inferior turbinate resection and bipolar radiofrequency ablation for treatment of chronic hypertrophy rhinitis are effective modality for the treatment of chronic hypertrophy rhinitis.

Adolescent↗
PubMed1990

[Abnormal platelet function and ultrastructure in patients with severe viral hepatitis].

A study of aggregation and release function of platelet and its ultrastructure in 27 patients with severe viral hepatitis (SVH) was carried out. The results showed that a) the maximum aggregation rate (MAR) decreased markedly; b) platelet 5-HT decreased strikingly and plasma 5-HIs increased significantly; c) the change of MAR was in positive correlation with that of platelet 5-HT and platelet 5-HT/plasma 5-HIs and the change of platelet 5-HT was in negative correlation with that of plasma 5-HIs; d) the ultrastructural abnormalities of platelet suggested its renewal, denaturation and activation in vivo. These results indicate that the abnormal platelet function and ultrastructure in patients with SVH are mainly related to the activation of platelet in vivo.

Adult↗
PubMed2006

[Effect of ouabain on cardiac function and myocardium ultrastructure of rat].

OBJECTIVE: To investigate the changes in rat cardiac function and myocardium ultrastructure in response to ouabain treatment. METHODS: Twenty-four male SD rats were randomized into two equal groups to receive daily intraperitoneal injection of ouabain or saline for 4 consecutive weeks, and their systolic blood pressure (SBP) was recorded weekly. After 4 weeks of injection, echocardiography was performed and the hemodynamic parameters were measured by invasive cardiac catheterization, and the changes in myocardium ultrastructure observed using transmission electron microscopy. RESULTS: After 4 weeks of ouabain injection, no significant changes in the mean SBP occurred in comparison with the saline group, but echocardiographic examination showed significant increases in the left ventricular end-diastolic and end-systolic diameters, septum thickness, posterior wall thickness, left ventricular mass and isovolumetric relaxation time but significantly lowered E/A ratio, ejection fraction and fractional shortening after ouabain treatment (P<0.05). Invasive monitoring revealed significant attenuation of the left ventricular developed pressure, rate of pressure development (+dp/dt) and rate of pressure decay (-dp/dt), and increment of the left ventricular end diastolic pressure. Myofibrillar fragmentation, swelling of the cardiac myocytes, absence of the Z line, increases of the mitochondria and collagen fibers were found in ouabain group by transmission electron microscopy. CONCLUSION: Ouabain can induce left ventricular enlargement, cardiac wall thickening, myocardial ultrastructural alterations, systolic and diastolic dysfunction in rats before blood pressure elevation is detected, indicating that ouabain can directly cause cardiac damage in rats.

Animals↗
PubMed2006

[Impact of blastocystis hominis infection on ultrastructure of intestinal mucosa in mice].

OBJECTIVE: To observe the ultrastructural change ot intestinal mucosa in mice infected with Blastocystis hominis, and to study the pathogenic mechanism of B. hominis infection. METHODS: 20 Kunming mice were randomly divided into 4 groups: group A treated with immunosuppressant (dexamethasone), group B without immunosuppressant, group C as normal control and group D as immunosuppressant control. Groups A and B were then orally infected with 20(4) cysts of B. hominis. Groups C and D were treated as control by infusing same volume of Locke's solution. Six days after inoculation, mice in each group were killed and mucosa of ileocecum was observed by transmission electron microscope (TEM) and scanning electron microscope (SEM). RESULTS: Under SEM, B. hominis located in enteric cavity and on the surface of ileocecum mucosa. Individual parasites also invaded into mucosa and its fold. Partial destruction of microvilli on the mucosa was observed. TEM observation indicated a reduction of microvilli on the surface of absorptive cells. Mitochondrial edema, rough endoplasmic reticulum dilatation and degranulation were found on absorptive cells and goblet cells. Lymphocyte infiltration and eosinophilia were found in intercellular stroma. Pathological changes in group A were more serious than that of group B. No abnormal change on the mucosal ultrastructure was found in groups C and D. CONCLUSIONS: B. hominis infection causes significant ultrastructural lesion on the ileocecal mucosa in mice. Immune status of the mice can affect the degree of the lesion due to infection.

Animals↗
PubMed1991

Mitochondrial ultrastructural and molecular changes induced by zidovudine in rat hearts.

Zidovudine (azidothymidine (AZT)) inhibits human immunodeficiency virus replication, prolongs survival, and delays progression of acquired immune deficiency syndrome. We determined AZT-induced molecular and ultrastructural changes in the rat heart. Rats (3 per group) were given drinking water with or without AZT (0.2 to 1.0 mg/ml; 29 to 102 mg/kg/day). After 21, 35, or 49 days, hearts were glutaraldehyde-fixed by abdominal aortic perfusion, processed, and examined by transmission electron microscopy. In parallel, myocardial RNA was extracted from hearts (AZT dose: 1 mg/ml; 35 days) and subjected to Northern analysis using cDNA probes for: alpha c-actin, troponin C, mitochondrial creatine kinase and malate dehydrogenase, a portion of the mitochondrial genome containing cytochrome b coding region (pMM26), and glyceraldehyde-3-phosphate dehydrogenase. Results showed marked and widespread cardiac mitochondrial swelling with fractured and disrupted cristae after 35 days of 1 mg/ml AZT. After a 14-day recovery, these ultrastructural defects did not reverse. Changes were not present in myocardium after 21 days of AZT nor after 35 days of lower dose AZT (0.2 mg/ml). Mitochondrial cytochrome b mRNA expression was depressed in AZT-treated rat hearts (35 days; 1 mg/ml AZT). mRNAs encoding glyceraldehyde-3-phosphate dehydrogenase, alpha c-actin, troponin C, mitochondrial creatine kinase, malate dehydrogenase, and mitochondrial ribosomal RNAs remained unchanged. AZT disrupts cardiac mitochondrial ultrastructure and expression of mitochondrial cytochrome b mRNA in a dose- and time-dependent fashion. The mechanism of AZT cardiotoxicity may relate to inhibition of mitochondrial DNA replication (at the level of DNA polymerase gamma) as postulated by others.

Animals↗
PubMed2006

Changes in the function and ultrastructure of vessels in the rat model of multiple low dose streptozotocin-induced diabetes.

In this study we investigated functional changes in the femoral artery and ultrastructural alterations in mesenteric vessels and capillaries in the rat model of multiple low dose streptozotocin (STZ)-induced diabetes. Participation of oxidative stress in this model of diabetes was established by studying the effect of the pyridoindole antioxidant stobadine (STB) on diabetes-induced impairment. Experimental diabetes was induced by i.v. bolus of STZ (20 mg/kg) given for three consecutive days to male rats. At the 12(th) week following STZ administration, the animals revealed typical signs of diabetes, such as polyphagia, polydypsia and polyuria. There was no weight gain in the diabetic groups throughout the experiment. No exitus occurred in any group. Diabetes was characterised with high levels of plasma glucose, no significant changes in lipid metabolism, decreased serum levels of glutathione, increased serum levels of the lysosomal enzyme N-acetyl-beta-D-glucosaminidase (NAGA), injured endothelial relaxant capacity of the femoral artery and alterations in ultrastructure of mesenteric arteries and capillaries. Antioxidant STB in the dose of 25 mg/kg body weight i.p. (5 times per week) did not influence glucose levels, however, it mitigated biochemical, functional and ultrastructural changes induced by diabetes, suggesting a role of reactive oxygen species in diabetes-induced tissue damage.

Animals↗
PubMed1991

Changes in development and ultrastructure of Aspergillus niger mycelium, strain with increased tolerance to toxic substances from beet molasses.

Effects of a defoamer and toxic molasses compounds on development and ultrastructure of A. niger mycelium, strain Z, characterized by high tolerance to these substances and producing citric acid in surface fermentation on proper molasses media with 70% yield were presented. Spumol BJ in concentration of 5 microliters/100 cm3 as well as toxic molasses compounds stimulated the process of swelling and germinating of conidia. Moreover, giant conidia, unable to germinate, appeared. Developing mycelium with dispersed hyphae became mucilaginous after 17-20 h culture, which indicated the process of sinking but after 24 h some part of the mycelium developed normally. Electron microscopic observations of mycelium developing in the presence of the toxic substances showed along with electron-transparent cytoplasm in a consequence of decrease in ribosome number, changes in ultrastructure of mitochondria. It may be assumed that one of the reasons of the above described abnormalities in development and ultrastructure of mycelium was a disturbance of respiration processes. The appearance of deposits of electron-dense material in mitochondria suggested the existence of a defence mechanism, eliminating toxic substances.

Aspergillus niger↗
PubMed1975

Ultrastructural myocardial changes produced by viruses.

Some of the ultrastructural pathological alterations in the myocardium produced by viral infections with members of the picornavirus group are described. These alterations varied from mild to severe, with necrosis. In animals infected with Coxsackie B1 virus and EMC virus, readily identifiable viral crystals were frequently found in association with the myocardial lesions by means of electron microscopy. The electron microscope made it possible to study vary early myocardial changes which were not detected with the light microscope. Although the ultrastructural myocardial changes in rheumatic fever have received little attention, the light and electron microscopic findings in the myocardium and valves of the viral-infected animals described here closely resemble those described in man in association with so-called rheumatic heart disease. The type of investigations presented forms a good model for the study of the natural history of ultrastructural pathology produced in all parts of the heart by viruses.

Adolescent↗
PubMed1991

Human lung-derived mature mast cells cultured alone or with mouse 3T3 fibroblasts maintain an ultrastructural phenotype different from that of human mast cells that develop from human cord blood cells cultured with 3T3 fibroblasts.

Culture systems designed to maintain or develop human mast cells have proved difficult, yet these systems would provide valuable resources for future investigations of human mast cell biology. Cocultures of either isolated mature human lung mast cells (Levi-Schaffer et al., J Immunol 1987, 139:494-500) or human cord blood mononuclear cells (Furitsu, Proc Natl Acad Sci USA 1989, 86:10039-10043) with 3T3 embryonic mouse skin fibroblasts have implicated fibroblasts as an important factor in the successful maintenance and development of human mast cells in vitro. The authors cultured isolated, mature human lung mast cells either with or without 3T3 cells for 1 month and examined their ultrastructural phenotype. Mast cell viability in each circumstance was equivalent, but mast cell yield was improved in the presence of 3T3 cells. The ultrastructural phenotype was identical in both culture systems. Mast cells were shown to maintain the phenotype of their in vivo lung counterparts (ie, scroll granules predominanted, and numerous lipid bodies were present). This ultrastructural phenotype differs from that of mast cells that develop in cocultures of human cord blood cells and 3T3 cells, where developing mast cells with crystalline granules and few lipid bodies prevail, a phenotype much like that of human skin mast cells in vivo (Furitsu, Proc Natl Acad Sci USA 1989, 86:10039-10043).

3T3 Cells↗
PubMed1991

Peripheral nerve sheath tumours: an ultrastructural study of 30 cases.

This report deals with the ultrastructural observations of 30 peripheral nerve sheath tumours [PNST], which include 25 schwannomas of acoustic nerve, one schwannoma of cauda equina, one neurofibroma from a case of Von Recklinghausen's disease, one pigmented neurofibroma of spinal nerve root and a malignant schwannoma of frontal region. Interdigitating slender cytoplasmic processes covered with a continuous layer of basal lamina constitute the single most important ultrastructural attribute of Schwann cells. Myelin formation was encountered in the cell processes of four out of 25 acoustic schwannomas. In four cases Microtubular arrays identical to that in an axon were seen in Schwann cells. These two observations require further support by additional cases of PNST studies by electron microscopy. The neurofibroma consisted only of Schwann cells and no ultrastructurally identifiable perineurial cells or fibroblasts were detected. The cells in the pigmented neurofibroma revealed submicroscopic features of both Schwann cell and melanocyte, indicating their common ancestry. A unique case of malignant schwannoma arising from frontal meninges is illustrated and it is emphasized that electron microscopy is mandatory for a correct histogenetic diagnosis of malignant tumours which occur at unexpected anatomical sites.

Adult↗
PubMedDate not supplied

An ultrastructural study of the synovial fluid (S.F.) in rheumatoid arthritis versus ankylotic spondylarthritis.

Our studies focused on the cytomorphological and ultrastructural analysis of ten synovial fluid (S.F.) samples from patients with serum positive rheumatoid arthritis (R.A.) (latex 1/1280, 1/640 and Waaler-Rose 1/1024, 1/1512) as compared to five S.F. sampes from patients with peripheral ankylotic spondylarthritis (A.S.). The cytomorphological investigation aimed at defining the cellularity, ragocytosis and synoviocytogram. We found out that the average number of cells (R.A. = 8060/mm3; A.S. = 6100/mm3), percentage of ragocytes (R.A. = 75%; A.S. = 25%), polymorphonuclear cells (R.A. = 70%; A.S. = 58%), degradative polymorphonuclear cells (R.A. = 7%, A.S. = 3%) and phagocytic mononuclear cells (R.A. = 16%; A.S. = 13%) are by far larger in R.A. than in A.S., whereas the lymphocyte percentage is much more reduced (R.A. = 13%; A.S. = 26%). Ultrastructurally, the rheumatoid S.F. ragocytes present specific intracytoplasmic inclusions and phagolysosomes pointing to an endocytotic activity. At the level of the degradative polymorphonuclear cells (7% cytomorphologically confirmed), the alteration of the granular-fibrillar structure of the nucleus and the presence of some cytoplasmic lysis areas were associated with the absence of cellular organelles. We also noticed cellular and collagen detritus. In A.S. the ultrastructural effect on the polymorphonuclear cells is much more reduced (3%) as compared to R.A. and resides in the dilatation of both mitochondrial cristae and granularendoreticular cisternae as well as in a slight concentration of the fibrogranular nuclear matter. The cells are considerably active in endocytosis. The phagocytotic mononuclear cells of the rheumatoid S.F. and A.S. are morphologically identical to the immunologically activated macrophages.(ABSTRACT TRUNCATED AT 250 WORDS)

Arthritis, Rheumatoid↗
PubMed1991

The myocardial ultrastructure in three amphipod species from Lake Baikal.

The heart ultrastructure of several crustacean species has previously been studied. Special interest has been paid to the development of the membrane systems of the cardiac myofiber relative to the different sarcomeric levels. This system seems to give phylogenetic information, but there still remains some uncertainty concerning its reliability. Is it affected by the size of the species, or is there any geographical variation within the different crustacean orders? The aim of this study is to compare the heart ultrastructure of some large amphipids from Lake Baikal(Acanthogammarus albus, Parapallasea puzylli and Poekilogammarus sukaczewi) with smaller amphipods from Europe and Northern America. It is shown that species size and geographical isolation do not seem to affect the membrane systems qualitatively. The isolation and adaptive radiation of the amphipods in Lake Baikal have not brought about any significant changes in the heart ultrastructure which separates them from other amphipod species. These findings support the use of cardiac membrane systems as a phylogenetic tool in the classification of Crustacea.

Actin Cytoskeleton↗
PubMedDate not supplied

[Early ultrastructural reactions in various parts of the visual analyzer in guinea pigs after thermogenic microwave irradiation].

A single total radiation of guinea pigs by means of microwaves of thermogenic intensity (energy density stream 60 mVt/sm2) and exposition for 10 min produces ultrastructural reactions in various parts of the visual analyser, differing in their manifestation degree. The most essential alterative changes have been revealed in the retina, appearing in 6 h after radiation, as degeneration of the membrane disks of the photoreceptors and as enhancement of phagocytic activity of pigmentocytes, and immediately after the radiation--as destructive disturbances of mitochondria in radial glyocytes and as reaction of the synaptic apparatus. In the cerebral visual centers a higher reactivity of neurons of the external geniculate bodies than in the visual cortex is noted, but ultrastructural disturbances of the hematoencephalic barrier and synapses of the visual cortex are more manifested. Early ultrastructural changes in the optic nerve are least manifested.

Animals↗
PubMed1991

An ultrastructural evaluation of the relationship between epithelial rests of Malassez and orthodontic root resorption and repair in man.

Contrary to previous reports, epithelial cell clusters with ultrastructural features similar to classically defined epithelial rests of Malassez were found, for the first time, in areas of repairing orthodontic root resorption. These observations were made on the buccal root surface of premolars extracted for orthodontic purposes from adolescent patients who had required rapid maxillary expansion. Ultrastructurally, the epithelial clusters ranged in size from 2-8 cells and were characterized by the presence of true desmosomes (macula adherens) and tonofilaments. Certain ultrastructural features of the epithelial cell clusters indicate that they may be involved in mediating repair cementogenesis subsequent to migration into the resorption bay.

Adolescent↗
PubMed1991

Ultrastructural demonstration of peroxidase expression in acute unclassified leukemias: correlation to immunophenotype and treatment outcome.

The lineage affinity of 57 cases of acute unclassified leukemias (AUL) was reevaluated by ultrastructural analysis of peroxidase expression (POEM) in combination with immunophenotyping and analysis of immunoglobulin gene configuration. Twenty-three cases of myeloid and three cases of megakaryocytic differentiation were identified by detection of ultrastructural myeloperoxidase (UMPO) and platelet peroxidase (UPPO). No significant correlation was noted between myeloid marker expression and POEM positivity, whereas presence of CD 19 or CD 24 antigen significantly correlated with POEM negativity (P = .001 and .023, respectively). Ig gene rearrangements including oligoclonal patterns were also recorded in 8 of 14 UMPO+ patients tested. Fourteen UMPO+ patients responded poorly to an ALL/AUL chemotherapy regimen with a low complete remission (CR) rate of 29% and a short median remission duration (MRD) of 5 months. The POEM- patients proved very heterogenous with respect to immunophenotype and Ig gene rearrangement. Seventeen of 21 patients tested had Ig gene rearrangements, including oligoclonal patterns. Combined data suggest that a proportion of these cases probably derive from a very immature lymphoid progenitor cell, particularly because 15 POEM- AUL patients showed a response to ALL/AUL chemotherapy comparable to that observed in patients with definitive acute lymphoblastic leukemia (ALL) (CR rate 80%, MRD 20 months). Thus, ultrastructural analysis of peroxidase expression can provide decisive prognostic information in AUL patients.

Acute Disease↗