Journal of submicroscopic cytology and pathology最新文献

The sperm ultrastructure of Bufo schineideri and B. granulosus consists of entwined seminiferous tubules formed by groups of germ cells and Sertoli cells. The spermatozoa of B. schineideri and B. granulosus measure about 66.7 microm and 85.4 microm in length, respectively. The head measures approximately 24.8 microm in B. schineideri and 17.7 microm in B. granulosus and consists of a single vesicle acrosomal, subacrosomal cone and nucleus. The midpiece measures approximately 3.8 microm in B. schineideri and 2.5 microm in B. granulosus and presents a mitochondrial collar around the tail. The tail consists of a typical axoneme, 9 + 2 microtubules, paraxonemal rod, axial sheath and axial fiber. The axial fiber extends through an electrondense structure that supports the undulating membrane. The structure and ultrastructure of the spermatozoa of the species here described are similar to the majority of sperm found in the other bufonids and may be a contribution for future phylogenetic analysis.

Effect of albendazole, metronidazole and nitazoxanide on the viability and structure of Giardia lamblia cysts isolates from infected children. The viability was evaluated by inducing excystation in a low-pH solution followed by an incubation in TYI-S culture medium. Nitazoxanide exhibited potent inhibitory effect (100%), metronidazole (79%) and albendazole (31%). The analysis among groups indicated a rs = 0.75 and p < 0.05. By TEM the cysts incubated with albendazole did not show morphological changes; with metronidazole, the formation of residual bodies in the nucleus border was observed. Incubated with nitazoxanide the damage to the cyst wall was evident, with the formation of areas with a granular content and the presence of cytoplasmic components in the peritrophic space. Our results propose that nitazoxanide showed a high effect on the viability and structure of G. lamblia cysts.

The aim of our study was to analyze the morphological events in the skeletal muscle of the Nile tilapia (Oreochromis niloticus) after a traumatic lesion. Thirty-two fish were used, on which a small longitudinal incision was made in the muscle. The fish were sacrificed after 7, 14, 21, and 42 days and muscle samples were collected from the lesion and processed for morphological analysis. Muscle regeneration in the tilapia occurred gradually through the analyzed period, possibly due to the proliferation and differentiation of myosatellite cells, which were more morphologically evident 7 and 14 days after lesion.

In the attempt to develop a pre-embedding immunoelectron microscopic method with improved ultrastructral morphology, we examined an antigen retrieval (AR) method using citraconic anhydride, and compared the effects of glutaraldehyde fixation with routine paraformaldehyde fixation in the pre-embedding immunoelectron microscopic method with reference to the localization of surfactant-associated pro-protein C (proSP-C) in the lung. The glutaraldehyde-fixed tissues were immunostained after AR in 0.05% citraconic anhydride solution, pH 7.4, at 98 degrees C for 60 min. In routine pre-embedding immunoelectron microscopic method using paraformaldehyde fixation, proSP-C positive products were distributed sporadically in the type II alveolar epithelial cells. In glutaraldehyde-fixed tissues without the AR method, proSP-C products were not detected, however after AR in citraconic anhydride proSP-C positive products were distributed specifically, in rough endoplasmic reticulum membranes, Golgi complex membranes, multivesicular bodies and osmiophilic lamellar bodies. The positive proSP-C products also showed lattice-like structures in the alveoli. Thus, the present AR method provides successful pre-embedding immunoelectron microscopy of glutaraldehyde-fixed tissues.

The purpose of this study was to evaluate the host response of a human and a porcine derived acellular dermal tissue (ADT) implanted in the subcutaneous tissue of a rat model. Two subcutaneous pockets were surgically created along the dorsal midline of 25 rats (5 rats/group). The human ADT was placed superiorly and the porcine ADT, inferiorly. The animals were sacrificed at 07, 15, 30, 60 and 180 postoperative days (PO) and the ADTs and surrounding soft tissues were assessed for ultrastructural evaluation by transmission electron microscopy. The ultrastructural findings were similar in both materials. Normal collagen and elastic fibers bundles were observed during all experimental moments, as well as macrophages presenting cytoplasmic enlargements digesting cellular portions after 15 PO. From 30 until 180 PO, vacuolar structures filled with an amorphous, electron-transparent substance, were present inside and outside the fibroblasts. Both human and porcine ADT showed similar pattern of ultrastructural response when implanted in the subcutaneous tissue of rats. The porcine ADT appears as a good alternative to be used as a biomaterial.

Many factors play a role in the development of atherosclerotic lesions. One of the leading risk factors for development of atherosclerosis is familial hypercholesterolemia (FH). FH is a genetic disease characterized by a deficiency, and/or mutation, of receptors for low density lipoprotein (LDL) on the plasmalemma of endothelial cells (EC), a high level of low density lipoprotein in the plasma, and early, spontaneous development of atherosclerosis and skin xanthoma. In this review we describe Watanabe heritable hyperlipidemic (WHHL) rabbits, which represent such an animal model for human FH. This strain of the rabbits is characterized by a genetic deficiency or mutation of functional LDL receptors and develops severe atherosclerosis, which is pathologically similar to familial homozygous hyperlipidemic patients. The most completely characterized animal model is the Watanabe rabbit, a model of homozygous and heterozygous type IIa hypercholesterolemia related to an LDL receptor deficiency. Additional manipulation such as aortic injury in this rabbit model induces the development of atherosclerotic lesions that are structurally similar to those found in humans. Thus, this model of hypercholesterolemia fulfils the above criteria set, i.e. it is able to provide new insights for a better understanding of the pathogenesis of atherosclerosis and for testing new treatment strategies.

Lysosome alterations and lipofucsin content of nerve cells, capillary endothelial cells and pericytes were examined in the anoxic-ischaemic brain parenchyma of thirty two patients with congenital hydrocephalus, complicated brain traumatic injuries, brain tumours and vascular anomalies. Cortical biopsies of frontal, parietal and temporal cortex were processed for transmission electron microscopy. In oedematous non pyramidal and pyramidal nerve cells, lysosomes showed fragmentation of their limiting membranes and an associated dense granulation. Areas of cytoplasmic focal necrosis were observed surrounding the lysosomes. Lipofucsin granules were also observed in neonate and infant patients with congenital hydrocephalus, suggesting that lipofucsin formation is a life span process. Lysosomes coexisting with an increased amount of lipofucsin granules were observed in young and adult patients with brain trauma, tumours and vascular anomalies. Phagocytic astrocytes and activated oligodendroglial cells showed the overall spectrum of an altered endosomal/lysosomal system. Lipofucsin granules and multivesicular bodies also were distinguished in endothelial and pericyte cells. The role of released and activated lysosomal enzymes is discussed in relation with the cytoplasmatic focal necrosis of nerve cells and the genesis of moderate and severe oedema.

The spermatozoon of the pikeperch, Sander lucioperca represents a new type of sperm organization. It differs in several parameters from Perca fluviatilis, i.e., the cell dimensions, the organization of the midpiece, and the structure of nucleus, mitochondria and centriolar complex.

Adult male lizards (Mabuya carinata) were studied during breeding and non breeding seasons to determine the regional and seasonal differences if any in the vas deferens and to compare ultrastructural features of luminal epithelial cells with those of endotherms. The vas deferens of the lizard is a convoluted tube extending from the epididymis to the hemipenis passing over the kidney. Based on morphometric data of luminal diameter and epithelial cell height three distinct regions viz; proximal, middle and distal regions were identified in the vas deferens. The epithelium is surrounded by a thin layer of lamina propria, many layers of circular smooth muscle fibers and an outer layer of visceral pleuro peritoneum. Based on cell and nuclear morphology and ultrastructure, five different cell types viz; principal cell, basal cell, mitochondria rich cell, halo cell and narrow cell were identified in the epithelium during both breeding and non breeding season. Principal cells and basal cells were more abundant in both seasons. The types of luminal epithelial cells of vas deferens of M. carinata and their ultrastructural features are similar to those of mammals. Further, vas deferens of M. carinata differs from mammals in having only circular smooth muscles in contrast to circular and longitudinal muscles of mammalian vas deferens. To the best of our knowledge this is the first report describing cell types of vas deferens, their ultrastructure and ultrastructural seasonal variations in reptiles.

An analysis of image distortion in connection with macular degeneration revealed that seeing objects requires brightness contrast enhancement. Thus macular degeneration changes neural interaction controlling bipolar cell responses to light stimulating photoreceptors to reverse spatial brightness contrast enhancement with the consequence that objects cannot be seen. This shows that the contrast of the retinal images is too low for vision without enhancement. However images consisting of randomly arranged small spots of different brightness are seen because of cones enhancing bipolar cell responses to rod input and rods enhancing bipolar cell responses to cone input. This residual vision and the observation that image distortion disappears at low light intensities reveal that macular degeneration is a functional disorder with intact photoreceptor function. The affection may therefore be caused by a reduction of blood flow through the choriocapillaries associated with ageing. The analysis of image distortion associated with the affection led to a simple way to determine the size of the affected retinal area, making it possible to follow the progression of the affection in a direct and simple way. Basic aspects are described of synaptic interaction within the information processing unit that determines the responses of the bipolar cells to photoreceptor input. This unit is the first information processing unit that has been revealed thanks to the extension of the analysis of the nervous system to the nanometer level at which information is processed. The minute size of the information processing unit, the special conditions for synaptic transmission combined with the short distances separating the synapses create special conditions for neural interaction at the nanometer level, establishing conditions for high speed neural communication.