Journal of submicroscopic cytology and pathology最新文献

To investigate the arrangement of organelles in normal rat liver hepatocytes, we examined liver tissues by electron microscopy. We also analyzed hepatocyte organelles by morphometry using the NIH image software. The smooth ER area appears as a network of branching tubules and contains many glycogen rosettes. The rough ER area presents lamellar plates and contains free polyribosomes. The Golgi complex area comprises the parallel smooth surface of associated vesicles and contains secretory granules, lysosomes and a few glycogens. Ratio of the cross-sectional area of hepatocytes shows the smooth ER area (60 +/- SD 1.5%), the rough ER area (35 +/- SD 1.4%) and the Golgi complex area (4 +/- SD 1.7%) of the total cytoplasm. The rough ER shows a dendrite pattern in a hepatocyte. Many mitochondria are spread between the smooth ER and the rough ER area. The smooth ER directly communicates with the rough ER, the Golgi complex cisternae at a forming face and the nuclear envelope. Anastomosing tubules with polyribosomes between the smooth ER and rough ER, between smooth ER and the nuclear envelope frequently. These results provide a basics at the cellular level for better understanding the experimentally induced changes and for improving the pathological hepatic diagnosis.

Nasal polyps are commonly associated with cystic fibrosis (CF) and also with idiopathic allergies, asthma, and aspirin intolerance. The pathogenesis of nasal polyp formation is controversial. The present study investigates the ultrastructure of thirteen nasal polyps surgically removed from seven CF patients and six non-CF (NCF) patients with allergic diseases, asthma, and aspirin intolerance. All nasal polyps showed focal edema, hyperplasia, atrophy, or squamous metaplasia of the epithelium. The lamina propria was moderately populated with small blood vessels and mucous glands and showed focal accumulation of inflammatory cells. The CF nasal polyps, however, revealed several specific characteristics: 1) minimal damage to the surface epithelium, 2) presence of a mucus blanket lining the apical epithelium, 3) occasional intracytoplasmic lumens, 4) continuous and fenestrated type capillaries, 5) numerous degranulated mast cells, 6) many plasma cells, often with atypical morphology and intracisternal Russell bodies, and 7) a smaller number of eosinophils as compared to the NCF nasal polyps. The results indicate significant differences between CF and NCF nasal polyps and support the multifactorial pathways theory of nasal polyp formation.

The difficulty in studying dengue virus (DENV) infection in humans and in developing a virus vaccine is the absence of a suitable animal model which develops the full spectra of the Dengue haemorrhagic fever (DHF) and Dengue shock syndrome (DSS). Despite the fact that viruses have been found in various animal tissues, we isolated DENV from tissues of adult BALB/c mice, inoculated with DENV serotype 2 (DENV-2) obtained from human serum. Viruses were ultrastructurally identified and immunolocalized by immunofluorescence techniques in C6/36 mosquito cell cultures, inoculated with tissues (liver, lung, kidney and cerebellum) macerate supernatant from mice, 48 h post-infection (p.i.). These organs, collected at the same stage of infection, were examined histologically. The histopathological analysis revealed focal alterations in all tissues examined. Liver contained focal ballooned hepatocytes, but without modifying the average diameter of the majority of hepatocytes. Sinusoidal lumen was significantly diminished at this stage but portal and centrolobular veins became congested. Lungs exhibited hemorrhagic foci in the alveolar space, vascular congestion and focal alveolitis. Cerebellar tissue showed rare foci of neuronal compactation (Purkinje cells) and perivascular oedema. In kidneys it was observed an increase in glomerular volume with augmented endocapillary and mesangial cellularity, with reactivity to anti-IgM in all glomeruli of infected mice. In conclusion, DENV-2 was found in all tissues examined early in the evolution of infection. Presence of viruses in tissues has mainly led to hemodynamic alterations with generalized vascular congestion and increased permeability, and mast cell recruitment in lungs. The latter could participate in the vascular modifications in tissues.

Surgical biopsies of frontal, parietal and temporal regions of thirty two patients with clinical diagnosis of congenital hydrocephalus, brain trauma, tumours, and vascular anomalies were examined with the transmission electron microscope. The main goal was to study the submicroscopic alterations of somatodendritic, axonal, and synaptic plasma membranes, cytomembranes, and the cytoskeleton. In both, moderate and severe oedema, fragmentation of plasma membrane, enlargement and focal necrosis of rough endoplasmic cisterns and nuclear envelope, detachment of membrane-bound ribosomes and reduction of polysome were observed. The degenerated myelinated axons exhibited discontinuities of the axolemma, disorganisation of multiple myelin lamellae, myelin sheath vacuolization, and formation of myelin ovoids. In severe oedema, synaptic disassembly was frequently found characterized by separate pre- and postsynaptic endings and loss of perisynaptic glial ensheathment. Fragmented and intact microtubules and actin-like filaments also were distinguished. The alterations of plasma membranes and cytomembranes are related with the anoxic-ischaemic conditions of brain parenchyma. The role of free radical and lipid peroxidation, disturbed energy metabolism, altered metabolic cascades, excitotoxicity, protein aggregation, and presence of extracellular oedema fluid is discussed in relation with the derangement of neuronal membranes.

The prostate is an accessory gland of the mammal reproductive system with great volume and high functional importance. Many works infer that, in addition to the androgenic ones, the estrogen can be associated with benign prostatic hyperplasia and prostatic cancer, but no conclusive evidence exists on the role of estrogen in normal prostatic and neoplastic tissue. The objective of this work was to evaluate the effects of chronic administration of estradiol benzoate on the lateral prostate of guinea pigs in the pre-pubescent, pubescent, post-pubescent and adult phases, with emphasis on the modifications provoked by this hormone on the glandular epithelium. The analyses of the estradiol-treated and control groups were investigated using histological procedures and transmission electron microscopy. The histopathological analysis of the lateral prostate in the treated group revealed areas where epithelial dysplasia was observed, assuming at some places a pattern of epithelial stratification characteristic of prostatic intraepithelial neoplasia. After ultrastructural analysis, the following were observed: enlargement of the internal membranes, heterogeneity in the cellular types, hypertrophy of the basal cells and apparent decrease of cytoplasmic organelles in some cells of the prostatic intraepithelial neoplasia. Still, a loss of cellular polarity was observed, along with nuclei of various forms, sizes and heights--as well as irregular chromatin distribution patterns. Such alterations were found mainly in pubescent, post-pubescent and adult animals subject to the chronic administration of estradiol. These findings reinforce the already existent data in understanding the role of estrogen in the etiology of prostatic diseases.

The chloroformic extracts from dried fresh leaves ofAzadirachta indica A. Juss. and Melia azedarach L. (Meliaceae) showed marked inhibitory activity on epimastigotes growth of Trypanosoma cruzi, evidenced by 96-wells microtiter plate bioassay and radioactive thymidine incorporation experiment. Each chloroformic extract was separated using silica gel and alumina column. In transmission electron microscopy the bioactive chromatographic fractions caused ultrastructural changes in epimastigotes such as vacuolization probably induced by degeneration of the kinetoplast-mitochondrion complex, organelle degeneration, and cell division disruption. In spectral analysis these bioactive fractions seemed to be composed mainly of fatty acid mixtures.

The structure of the zona pellucida (ZP) was analyzed in mouse oocytes collected soon after ovulation and in others retrieved 20 h after. The conventional methods for electron microscopy and the alcoholic PTA staining procedure which preferentially contrasts lysine-rich proteins were employed. The ZP of aged oocytes showed several structural changes which were particularly observed after using the PTA procedure. In 82.14% of the aged oocytes the ZP appeared clearly composed of two different regions: an inner dense and an outer of low density. The ZP showed a fibrillar banded structure with a parallel arrangement of fibrillar threads in both the outer and inner regions. The in vitro fertilization analysis showed that only 16.85% of the aged gametes attained the two cell embryo stage in comparision to 66.93% shown by the freshly ovulated eggs. The non-fertilized oocytes showed that no sperm penetration through the ZP occurred.

The cortical biopsies of 31 patients with clinical diagnosis of congenital hydrocephalus, vascular anomalies, brain tumours and brain trauma were examined with the transmission electron microscope. A variety of swollen spine shapes were found: mushroom shaped, filopodic, lanceolated spines, and megaspines. The spines appeared axonless or making asymmetric synaptic contacts with swollen presynaptic axons. They exhibited a disrupted actin-like network, dilated endoplasmic reticulum profiles, oedematous clear or dense mitochondria, and clusters of free ribosomes. Some spines contained a hypertrophic cytoskeleton. The spine apparatus appeared generally swollen with clear and dilated cisterns. In severe brain trauma and tumours some spine apparatus appeared disorganised or atrophic. In complicated brain trauma with subdural haematoma or hygroma some degenerated spines displayed a high electron density. The ultrastructural findings suggest that alterations of the spines are responsible for the neurological symptoms exhibited by some patients, which imply a disturbance of cortical nerve circuits. The presence of axonless spines is symptomatic of a loss of nerve connectivity, and are expected to have a significant input on neurological and mental functions.

There has been a resurgence of interest in medical protozoology in the last twenty years or so mainly as a result of the recognition of HIV infection and the opportunistic protozoan infections associated with it. Many new species of microsporidia have been recognised as parasites causing human disease and several rare infections, such as isosporiasis, have become more commonly recognised, even in temperate climates. Some of the infections seen in temperate regions have arrived through foreign travel (tourism, work or immigration), sometimes exacerbated by immunosuppression (due to HIV, organ transplantation or malignancy). Importation of food from around the world and climate change (global warming) may also be contributing to the increase in previously rare protozoan infections now being seen in temperate regions. This article reviews the current status of these new and re-emerging human protozoan infections in temperate, rather than tropical locations.

Non tonotopic transmission between cochlear nuclei and other auditory and non-auditory nuclei in the brain is probably due to large axonal terminals (mossy fibers) innervating granule cell areas of cochlear nuclei. The origin of mossy fibers in the dorsal cochlear nucleus (DCN) is multiple, from other auditory or non-auditory nuclei but possibly also from intrinsic neurons. The present ultrastructural immunocytochemical study reports for the first time the presence of anterograde-labeled mossy fibers in the DCN of the rat after injection of the neural tracer WGA-HRP into 3 different nuclei. Labeled mossy fibers were seen in 9.0% of mossy fibers detected after tracer injection into the ipsilateral anteroventral cochlear nucleus, in 7.3% of mossy fibers after contralateral collicular injection, and 13.2% after contralateral cochlear nucleus injection. Most (over 95%) mossy fibers contained round vesicles, both large and small, and were likely excitatory terminals, but few showed flat-pleomorphic vesicles that contained the inhibitory neurotransmitters GABA and glycine. Most of the anterograde-labeled ipsilateral mossy fibers containing small round synaptic vesicles, are probably derived from multipolar neurons within the ipsilateral anteroventral cochlear nucleus. After injections into the contralateral inferior colliculus, it was not possible to distinguish putative descending collicular mossy fibers from intrinsic mossy fibers. The latter would suggest the presence of an amplification pathway within the DCN, from collateral axons of pyramidal or stellate cells of the ipsilateral ventral cochlear nucleus to form glomeruli with granule-unipolar brush cells. After injection into the contralateral cochlear nucleus, it was not possible to distinguish between commissural mossy fibers and those derived from ipsilateral recurrent axon-terminals of commissural neurons within the DCN or the ventral cochlear nucleus. Despite this limitation, the present observations show that extrinsic or intrinsic mossy fibers reach granule cell areas in layers 2 and 3 of the DCN and form glomeruli of large or small dimension (1.5-4 microm) with unipolar brush and granule cells. These mossy fibers probably carry a fast excitatory non-tonotopic input which may influence the electrical response of granule cell areas.