PubMed Health⌕ Search

Biomedical subjects

E L Portiansky

Publications and source records attributed to E L Portiansky.

At least 19 recordsLinked to original sources
PubMed2006

Restorative effect of insulin-like growth factor-I gene therapy in the hypothalamus of senile rats with dopaminergic dysfunction.

Insulin-like growth factor-I (IGF-I) is emerging as a powerful neuroprotective molecule that is strongly induced in the central nervous system after different insults. We constructed a recombinant adenoviral vector (RAd-IGFI) harboring the gene for rat IGF-I and used it to implement IGF-I gene therapy in the hypothalamus of senile female rats, which display hypothalamic dopaminergic (DA) neurodegeneration and as a consequence, chronic hyperprolactinemia. Restorative IGF-I gene therapy was implemented in young (5 months) and senile (28 months) female rats, which received a single intrahypothalamic injection of 3 x 10(9) plaque-forming units of RAd-betagal (a control adenoviral vector expressing beta-galactosidase) or RAd-IGFI and were killed 17 days post-injection. In the young animals, neither vector modified serum prolactin levels, but in the RAd-IGFI-injected senile rats a nearly full reversion of their hyperprolactinemic status was recorded. Morphometric analysis revealed a significant increase in the total number of tyrosine hydroxylase-positive cells in the hypothalamus of experimental as compared with control senile animals (5874+/-486 and 3390+/-498, respectively). Our results indicate that IGF-I gene therapy in senile female rats is highly effective for restoring their hypothalamic DA dysfunction and thus reversing their chronic hyperprolactinemia.

Adenoviridae↗
PubMed2006

Characterization of interstitial cells of Cajal in bowel of cattle (Bos taurus).

Interstitial cells of Cajal (ICC) have been described in the gastrointestinal tract of different mammals including humans, horses, pigs, rats, dogs, mice and guinea-pigs. In the present study, ICC were identified in the jejunum of Bos taurus using polyclonal anti-c-Kit antibodies in immunohistochemical assays. Vimentin and desmin intermediate filaments were also determined using monoclonal antibodies. ICC were found in the tunica muscularis either in a palisade distribution pattern between the outer longitudinal and the inner circular layers (ICC-MP) or freely distributed in clusters in the longitudinal layer (ICC-LM). Morphometric studies determined that ICC have a fusiform shape presenting cytoplasmic prolongations. ICC were positive to c-Kit and vimentin antigens but negative to desmin. We have observed and described for the first time the presence of ICC in a ruminant. As observed in the aforementioned mammals, bovine ICC were associated with the myenteric plexus. Nevertheless, the presence of widespread ICC in the longitudinal muscular layer of the jejunum differs from previously described studies of other mammals.

Animals↗
PubMed2005

Interaction of Tritrichomonas foetus with the reproductive tract of experimentally infected female BALB/c mice: ultrastructural evaluation.

The interaction of Tritrichomonas foetus with its host is a complex process that involves colonisation, attachment and persistence. The goal of the present study was to describe the interaction of T. foetus with the genital tract using a model of non-oestrogenised female BALB/c mice which had been intravaginally infected with a suspension of T. foetus during oestrus. Animals were sacrificed after 10 weeks and the uteri fixed and processed for light and electron microscopy. Ultrastructural analysis showed that the attached protozoa interacted with the mucosa through a somal projection. With an amorphous secretion at the protozoa-host cell interface. There was no direct contact between the protozoal plasma membrane and the epithelial cell membrane. Our results demonstrated the participation of an active phagocytosis and the destruction of T. foetus by eosinophils.

Animals↗
PubMed2004

Lectin binding patterns in hyperplastic and metaplastic bullock prostate tissues after diethylstilbestrol administration.

Hyperplasia and squamous metaplasia of the prostatic epithelium are conditions induced by oestrogens. Diethylstilbestrol (DES) has been banned from cattle used for beef production because of the health risks. The potential use of molecular markers for the detection of illegal oestrogen administration was evaluated by taking samples of prostatic tissue from control bullocks, bullocks which had been treated with oestrogens, and bullocks sacrificed 21 and 90 days after a single dose of DES. The expression of the glycoconjugates was examined by lectinhistochemistry and the lectin binding pattern was characterised in epithelium and connective tissue. In the animals sacrificed after 21 days there was an increase in the binding of one lectin (JAC) and there was an increase in the binding of one of the other lectins (DBA) in the animals sacrificed after 90 days. An increase in SWGA lectin staining was observed in the bullocks that had probably been treated with oestrogen and in the animals sacrificed 90 days after the inoculation with DES. There were also differences between the binding of SWGA in the control bullocks and the other groups.

Animals↗
PubMed2003

Cutaneous lymphangiosarcoma in a young dog: clinical, anatomopathological and lectinhistochemical description.

Lymphangiosarcoma is a rare tumour in domestic animals arising from lymphatic endothelial cells. Occasionally, microscopic differentiation with haemangiosarcoma may be difficult. The aim of the present study was to describe a lymphangiosarcoma in a 1-year-old female Doberman Pinscher dog and to characterize its lectinhistochemical binding pattern as compared with that of haemangiosarcoma. The dog was presented because of a cutaneous painful swelling located in the left axilla. Histological diagnosis confirmed lymphangiosarcoma. The dog was killed. Necropsy revealed mediastinal lymph nodes' involvement. Twenty lectins were tested in tissue sections of this case as well as in four haemangiosarcomas from other dogs. Staining intensity was issued upon optical density determinations. Percentage of lectinhistochemical staining area was also conducted. RCA-I showed the most intense and wide distributed labelling pattern for lymphangiosarcoma. PHA-E was the counterpart for haemangiosarcoma. Should similar results be obtained in further studies, such differences could aid in the differential diagnosis between lymphangiosarcoma and haemangiosarcoma when histological pictures were not conclusive.

Animals↗
PubMed2002

Collagenous and elastic system fibres in the aorta of cattle poisoned by Solanum glaucophyllum.

The proportions of fibres of the collagenous and elastic systems were measured in the aortas of three normal heifers and in nine heifers given the calcinogenic plant Solanum glaucophyllum for 15, 30 or 60 days. There were decreases in the amount of collagen relative to reticulin, and in the proportion of elastic fibres which were related to the period of dosing. These changes may have an adverse influence on the animals' cardiovascular function.

Analysis of Variance↗
PubMed2002

Lectin histochemical study of lipopigments present in the cerebellum of Solanum fastigiatum var. fastigiatum intoxicated cattle.

This study was carried out to investigate the pattern of lectin binding in the cerebellum of calves poisoned with Solanum fastigiatum var. fastigiatum. For the experimental reproduction of the illness, S. fastigiatum var. fastigiatum was collected from farms where the intoxication occurs. The dried ground plant was administered to two 1-year-old cattle by a ruminal cannula. The animals received 5 g/kg b.w. daily, 5 days a week, during periods of 107 and 140 days. After these periods the animals were bled to death. For the histological study, transverse sections of the cerebellum were used. Paraffin-embedded sections were incubated with the following biotinylated lectins with different specificity: Concanavalia ensiformis (Con-A). Glycine max (SBA). Dolichos hiflorus (DBA), Ulex europeus-I (UEA-I). Triticum vulgaris (WGA), succynyl-WGA (sWGA). Arachis hypogaea (PNA), Ricinus communis-I (RCA-I) and Bandeirea simplicifolia-I (BS-I). Avidin-biotin-peroxidase complex was applied as a detection system. Purkinje cells showed vacuolation in the pericaryon. The stored material present in the cells reacted strongly with the following lectins: Con-A. sWGA, WGA and RCA-I. An irregular affinity was observed with PNA and DBA. The lectin-binding pattern was compatible with a glycolipid storage disease.

Animals↗
PubMed2001

Congenital cerebellar cortical degeneration in Holstein cattle in Southern Brazil.

A congenital progressive cerebellar disorder is described in Holstein calves. The clinical signs were progressive and were characterized by ataxia, hypermetria, a wide stance and fine head tremors. When the affected cattle were forced to run, the signs were exacerbated, leading to epileptiform attacks. Histological lesions consisted of a very selective cerebellar cortical degeneration, almost exclusively affecting the Purkinje cells. The disease affected 6 out of 200 Holstein calves from the same bull. However, results of mating tests of the bull with his daughters and granddaughters suggested that it was not hereditary (p = 0.0062) although an environmental-genetic interaction could not be ruled out.

Animals↗
PubMed2001

Paratuberculosis in red deer (Cervus elaphus): an immunohistochemical study.

In the present study, we compared the utility of immunohistochemistry with serological and histological results for the characterization of Mycobacterium avium ssp. paratuberculosis (M. paratuberculosis) in tissues of affected red deer. Bacterial isolation was considered the standard reference. Samples were taken from seven clinically affected animals with typical macroscopic lesions. The enzyme linked immunosorbent assay (ELISA) and the gel diffusion tests (GD) were used for serological determinations. Samples from intestine and mesenteric lymph nodes were processed for bacterial isolation and histology. M. paratuberculosis was isolated from all the animals. Histologically, lymph nodes displayed necrosis and mineralization at the cortical and medullar areas. Ziehl-Neelsen stained bacteria were numerous inside macrophages and Langhans-type giant cells. Giant and epithelioid cells and lymphocytes were prominent at the ileal mucous membrane. The immunostaining of M. paratuberculosis was very clear inside epithelioid and giant cells. Image analysis was carried out to determine the immunostained area. There was total agreement among the methods employed. Immunohistochemistry can be very useful when the microorganism cannot be recovered from tissues or faeces.

Animals↗
PubMed2000

Distribution of tyrosine hydroxylase-immunoreactive neurones in the diencephalon and mesencephalon of the coypu (Myocastor coypus).

The aim of the present study was to examine the catecholaminergic neurones located within the midbrain of the coypu, a South American hystricomorph rodent. The neuronal distribution of the catecholaminergic systems and morphological parameters of the immunostained cell bodies and fibres were investigated, using an immunohistochemical method. The brains of five coypu were fixed, immersed in gelatine-glycerol and cut in 40-micron slices using a freezing microtome. Samples were processed with ultrasound-based antigen retrieval and stained with labelled antityrosine hydroxylase monoclonal antibody. An image analyser was used to measure the neuronal bodies. The catecholaminergic neurones of the tuberoinfundibular system were mainly observed in the arcuate and periventricular nuclei with their axons projecting towards to the median eminence; they represented 28% of the global population of tyrosine hydroxylase-immunoreactive cells observed. Significant morphological differences were observed in comparison with the other two studied systems. Fifty per cent of total catecholaminergic neurones were detected in the nigrostriatal system distributed in the reticular and compact substance nigra. Most neuronal bodies had a fusiform aspect. The immunoreactive neurones of the mesolimbic system represented 22% of the total population. They were distributed around the interpeduncular nucleus. Two types of morphologically different catecholaminergic systems of the brain were established: hypothalamic neurones located in the periventricular and arcuate nuclei and mesencephalic neurones located in the substance nigra and interpeduncular nuclei. These systems showed morphological and probably physiological-pharmacological differences.

Animals↗
PubMed2000

Effects of plant-induced hypervitaminosis D on cutaneous structure, cell differentiation and cell proliferation in cattle.

Solanum glaucophyllum (Sg) (synonym S. malacoxylon) is a plant toxic to cattle due to its high levels of 1,25-dihydroxyvitamin D3 as glycoside derivatives. Sg causes a disease characterized by wasting and calcification of soft tissues. The effects of vitamin D are not only important in calcium homeostasis, but also in immune regulation, cell growth and cell differentiation. Skin samples in Sg-intoxicated and control heifers were studied histologically. Cellular differentiation and proliferation were analysed by immunohistochemical expression of cytokeratins, involucrin and proliferating cell nuclear antigen (PCNA). The results were obtained by image processing and analysis and were statistically evaluated. Sg-intoxicated cattle showed atrophy of epidermis and severe involution of hair follicles and of sebaceous and sweat glands. As judged by PCNA expression, cellular proliferation was reduced, even though the reduction was not statistically significant. The analysed markers of differentiation, e.g. involucrin and cytokeratins 10 and 11, changed in relation to Sg-poisoning. The possible pathogenesis of the skin lesions is discussed.

Animals↗
PubMed2000

Intermediate filament protein expression and sugar moieties in normal canine placenta.

In the female dog, the placenta is considered zonal, endotheliochorial and labyrinthic. The distribution of the intermediate filaments as well as the surface glycoproteins in the canine placenta are still unknown. The aim of the present study was to provide this information for further understanding of pathological conditions in the bitch. Samples were obtained from normal uterine horns at the end of gestation. Tissues were routinely fixed and stained. Monoclonal antibodies against cytokeratins, vimentin and desmin were used for immunohistochemical staining. UEA-1, PNA, RCA-1, SBA, DBA, WGA and ConA were used for the lectin histochemical staining. A computer morphometrical analysis was made. Statistical analysis was then accomplished. The results showed the maximum immunohistochemical percentage for vimentin in the supraglandular connective tissue, for pancytokeratin in the spongy zone and for desmin in miometrium. SBA showed the highest staining percentage in the gland cells of the spongy zone, while ConA was the highest in the syncytiotrophoblastic cells and gland cells of the deep glandular zone. The results obtained indicate that the lectin binding pattern is partially different from other animal species. On the contrary, the intermediate filament data coincide with similar observations from other mammals.

Animals↗
PubMed1998

Characterisation of cytotrophoblastic-like cells present in subinvolutioned placental sites of the bitch.

This paper describes an approach to study the cells present in the subinvolution of placental sites (SIPS), a pathological post partum condition of the bitch that causes persistent hemorrhage of the genital tract. The expression of intermediate filament proteins was examined to determine the fetal or maternal origin of the cytotrophoblastic-like cells found in this entity. Lectin binding on tissue sections were also studied to characterise cellular glycoconjugates. Image processing and morphometrical analysis of the histological images were done. The results revealed that the cells observed in bitches with SIPS expressed pancytokeratins but neither vimentin nor desmin, in coincidence with normal cytotrophoblasts. The lectin binding pattern of both types of cells was similar, with the only exception of Arachis hypogaea agglutinin (PNA) and Triticum vulgaris agglutinin (WGA). These observations, in addition to the non statistically significant differences between morphometrical characteristics of cytotrophoblastic and cytotrophoblastic-like cells in SIPS, might suggest the fetal origin of the latter cells which could play a role in the pathogenesis of this entity.

Animals↗
PubMed1996

The use of cyclophosphamide as an enhancer of the vaccine against foot-and-mouth disease.

The immunization of biungulate animals with killed foot-and-mouth disease virus (FMDV) requires periodic vaccinations due to a low vaccine immunogenicity. Therefore, FMDV antigens need to be combined with adjuvants such as aluminium hydroxide, saponin or oil emulsions. Animal handling for periodic inoculations, and the repeated doses of vaccines that have to be administered increase the commercialization costs. Moreover, the use of adjuvants may induce adverse effects. In the present work we show that it is possible to increase the life span of neutralizing antibodies in serum when a single dose of cyclophosphamide (Cy) is administered four days before vaccination with aluminium hydroxidesaponin FMDV vaccine.

Animals↗
PubMed1996

Increase of murine splenic natural antibody-secreting cells after cyclophosphamide treatment.

Administration of a low sub-immunosuppressive dose of cyclophosphamide (CY) to naive mice induced a marked increase in the number of splenic cells forming natural antibodies against unrelated antigens such as foot-and-mouth disease virus, keyhole limpet hemocyanin, horseradish peroxidase, or bovine serum albumin, as determined by an enzyme-linked immunosorbent assay spot technique. These results suggest that in mice there exists a repertoire of B cells forming natural antibodies which is restrained by an unknown mechanism and that CY is able to interfere with that restriction.

Animals↗
PubMed1995

Protective effect of lidocaine in the experimental foot-and-mouth disease pancreatitis.

Experimental infection of mice with foot-and-mouth disease virus (FMDV) induces a necrotizing pancreatitis of the exocrinar portion of the organ. The lesions are characterized by vascular congestion, edema and interstitial polymorphonuclear leukocyte (PMN) infiltrates. When infected mice were treated with different amounts of lidocaine (a local anesthetic, chemically defined as a tertiary amide compound), reduction in intensity of the pancreatic necrosis and in the number of PMN were observed. Even though lidocaine could interfere with FMDV post-replicative cytolytic mechanisms, it appears that protection against pancreatic necrosis is by attenuation of PMN presentation in the infected tissue.

Animals↗
PubMed1991

Cytotoxicity and cytoadherence of human and murine polymorphonuclear leukocytes against Junin virus infected targets in the absence of anti-viral antibody and complement.

Human and murine polymorphonuclear leukocytes (PMN) lysed L cells infected with Junin Virus (JV) in an in vitro system free of antiviral antibody and complement. Infected VERO cells proved to be resistant to the cytolytic effect. Murine PMN showed an increased adherence on JV-infected L cells but did not attach to VERO cells. The opposite was observed with human PMN, which did adhere to infected VERO cells but not to infected L cells. These results indicate that PMN activity may be an early mechanism of defense in JV infection by lysing virus-infected cells when no immune response has been established, and that cytoadherence is not a necessary step for target lysis.

Animals↗