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Biomedical subjects

A Jasiński

Publications and source records attributed to A Jasiński.

At least 19 recordsLinked to original sources
PubMed2006

Brains with different degrees of dysplasia show different patterns of neurodegenerative changes following pilocarpine-induced seizures. Histologic evidence of tissue damage correlated with MRI data.

OBJECTIVE: Brain dysplasias produced by irradiation with gamma rays at various stages of prenatal development cause different post-natal susceptibility to seizures. To detect possible determinants of this difference, patterns of degenerative changes in the dysplastic brains following pilocarpine-induced epilepsy were analysed. METHODS: Pregnant Wistar rats were exposed to a 1.0 Gy dose of gamma rays on gestation days 15 (E15) or 17 (E17). On post-natal day 60, their offspring received pilocarpine injections to evoke status epilepticus. Motor manifestations of seizure activity were observed continuously for 6 hours and rated. Six days following the status epilepticus, the rats were anesthetized and T(2)-weighted magnetic resonance (MR) images were obtained. Frontal sections of the brains were immunostained for immunoglobulins G (IgGs) to detect blood-brain barrier damage and IgG cell uptake and glial fibrillary acidic protein (GFAP) or S-100-beta protein to visualize astrocytes. Bandeiraea simplicifolia isolectin-B4 (BSI-B4) isolectin histochemistry was also performed to detect microglia/macrophages. RESULTS: Tissue damages within epileptic brains as observed by light microscopy generally reflected changes in magnetic resonance imaging (MRI) at similar locations. Brains of rats irradiated on E15 or E17 and showing epileptic symptoms at comparable intensity also displayed different distribution of the pathologic changes. Among other post-epileptic changes, in rats irradiated on E17 as well as controls, the laterodorsal and ventrolateral thalamic nuclei showed signs of severe degeneration. In rats irradiated on E15, the nuclei were free of such changes. CONCLUSIONS: The obtained data point to important differences in the pattern of propagation of epileptic activity in the dysplastic brains suffering from neuronal loss in functionally different structures.

Age Factors↗
PubMed2004

Analysis of the diffusion weighted MR microscopy data of excised spinal cord of a rat on the basis of the model of restricted diffusion.

Anisotropic diffusion in the excised rat spinal cord saturated with 0.9% saline was investigated using MR microimaging with b-values up to 8000 s/mm2 for different diffusion times. Non-exponential transversal diffusion decay found in white matter (WM) and gray matter (GM) was fitted with 2 components (the "fast" and the "slow"). Significantly smaller non-exponential dependence was found for the longitudinal diffusion in the WM. Obtained results corresponding to restricted diffusion in the range from approximately 2 to approximately 7 microm were correlated with axon diameter distribution in the WM obtained from transmission electron micrographs. It was concluded that observed diffusion anisotropy in the spinal cord might be entirely explained by presence of the slow transversal component, arising from the restricted diffusion. The strict analytical description of the diffusion decay in nervous tissue requires taking into account continuous distribution of the space-scale of the restricting barriers. The simplified two-component analysis may be applicable for visualization of the nervous tissue in clinical practice.

Animals↗
PubMed2004

The macromolecular polymers for the preparation of hydrodynamically balanced systems--methods of evaluation.

Evaluation of macromolecular polymers used as excipients for the preparation of hydrodynamically balanced systems (HBS) was carried out. Hard gelatine capsules were filled with polymeric substances belonging to various chemical groups (chitosan, sodium alginate, hydroxypropylmethycellulose--HPMC). The following properties of the HBS were investigated: density, hydration, erosion and floating force. The solvent penetration process into the HBS was visualized using magnetic resonance imaging (MRI) technique. Densities of the HBS in hydrochloric acid (0.1 M) ranged from 0.37 g/cm3 to 0.71 g/cm3. Each polymer demonstrated different hydration/erosion abilities and floating properties. The maximum floating force (F(float max)) for capsules size 0, ranged from 26.7 mN (sodium alginate) to 64.7 mN (chitosan). HBS formulations also varied in time to reach maximum floating force (T(float max)). HPMC and sodium alginate formulation reached F(float max) within half an hour after immersion, while in the case of chitosan formulations (deacetylation degree (d.d.) 66% and d.d. 93%), the time was 184 minutes and 218 minutes respectively. The floating properties of the dosage forms were reliant on type of the polymer and the medium-fasted state simulated gastric fluid (FaSSGF) or fed state simulated gastric fluid (FeSSGF). The size of the HBS influenced the floating force value. The mechanisms of erosion and swelling of the polymeric matrices play a dominant role in flotation of the dosage forms.

Alginates↗
PubMed2001

Immunohistochemical investigations of excitotoxicity in experimental spinal cord trauma.

The concept of "excitotoxicity" assumes that high concentration of glutamate (main excitatory neuromediator) acting through specific receptors leads to damage of cells due to an influx of calcium ions. Proteins called "excitatory amino acid transporters" (EAATs), present in astroglia, play important role in the removal of glutamate. We investigated the expression of GluR2 (glutamate receptor), EAAT1, and EAAT2 by immunohistochemistry in formalin-fixed, paraffin-embedded rat spinal cords, previously subjected to experimental mechanical trauma. In the injured spinal cords, an elevated immunoreactivity of GluR2 was noted even 10 min after trauma and was still observed 2 days after injury. Strong immunoreactivity was observed not only in many cells in gray matter but also in some cells in white matter (probably glial cells). In the injured spinal cords, we observed stronger (as compared with controls) expression of EAATs in the white matter, especially 6 hours after injury. The results support the role of excitotoxicity in mechanical trauma of spinal cord suggesting a possibility of long lasting elevated expression of glutamate receptor. It may help to understand and to explain beneficial action of "anti-glutamate" drugs, reported by other investigators.

ATP-Binding Cassette Transporters↗
PubMed2001

[Evaluation of efficacy of selected antiseptics for hands disinfection before surgical procedures].

The most important in surgical hands washing and disinfections is long-term and effective reduction of bacteria number. The aim of this study was to compare the efficiency of some antiseptic fluids used for surgical hands disinfection's (AHD 2000, Biotensid, Manopronto and Medi-Scrub PVP Iodine). 62 doctors and surgical nurses were examined. The material for the bacteriological examination was collected before and after hands disinfection's. The bacterial flora reduction have been presented as a percent and a logarithmic reduction ratio. All estimated antiseptic fluids were very potent and provided prolonged efficiency when the operation team complied with orders of hands washing.

Anti-Infective Agents, Local↗
PubMed1995

[Pancreatic ascites].

Two cases of pancreatic ascites have been presented. 1. A 29 year old man, heavy alcoholic, with fast growing ascites presented since long biochemic features of pancreatitis. The diagnosis of the pancreatic origin of ascites was made on the ground of the high level of amylase in the ascitic fluid. Conservative treatment was effectless. The patients refused surgical therapy. Then he died in septic shock. Autopsy confirmed the pancreatic origin of ascites. 2. A 43 year old man heavy alcoholic as well admitted because of fast growing ascites. As in the first case examination of the fluid confirmed the diagnosis of pancreatic origin of ascites. Again a high level of amylase and protein was found. After clinical treatment and parenteral nutrition the condition of the patient improved and he was dismissed 4 weeks later.

Adult↗
PubMed1993

[Attempt at evaluation of certain parameters of gastric secretion in patients with duodenogastric reflux].

There were four groups of patients: duodenal ulcer patients (32), duodeno-gastric reflux patients (31), patients with duodenal ulcer and reflux (33) and 12 healthy men. All of them aged 20-40. In all patients we performed gastroscopy, cholecystography, Kay's test for secretion and isotope proteolytic secretion test. High activity of proteolytic secretion in both groups of reflux patients was found. There were also the high percentage of false positive scores in endoscopy estimation of reflux, in comparison to the non-invasive isotope method. We suggest: reflux may be the important factor in duodenal ulcer pathogenesis; endoscopy cannot be used in duodeno-gastric reflux estimation.

Adult↗
PubMed1981

Vascular arrangement in the oral mucosa of Rana esculenta. Scanning electron microscopy of corrosion casts.

Corrosion casts of the blood vessels in the oral mucosa of Rana esculenta were examined by the scanning electron microscope. Special attention was paid to the palatine capillaries characterized by numerous blind diverticula. Microanatomy and topography of these peculiar vessels suggests their involvement in gas exchange. The diverticula of the capillaries visible in the casts in form of nodules of various shape and size were examined in detail.

Animals↗
PubMed1979

Blood vessels in the tongue of the kitten: scanning electron microscopy of microcorrosion casts.

The subepithelial blood vessels of the dorsal surface of the tongue in young kittens has been studied by scanning electron microscopy of micro-corrosion casts. These vessels entwine the vallate papillae distributed in the pharyngeal part of the tongue, form hairpin loops in association with the small conical papillae along the sides and at the tip of the tongue and establish regularly distributed subpapillary conglomerations over almost its entire oral part. These conglomerations lie directly on veins. Small arterioles reach the vessels surrounding the individual subpapillary conglomerations. By contrast with the arrangement of the superficial vascular bed in the tongue of the dog and some other mammals, no anastomoses between arteries and veins were observed in the kitten between the vessels which supply and drain the subepidermal capillaries.

Animals↗
PubMed1979

Scanning electron microscopy of microcorrosion casts of the vascular bed in the skin of the spotted salamander, Salamandra salamandra L.

Microcorrosion casts of blood vessels in the skin of the spotted salamander, Salamandra salamandra L., were studied using scanning eletron microscopy. The investigated vessels include a subepidermal network of respiratory capillaries and the vessels of poison glands. A hypothesis is proposed, according to which both types of vascular beds possess a common origin. Probable factors involved in the differentiation of the primary netword of the subepidermal vessels in larvae are indicated and speculation concerning the supposed mosaic type of circulation in the capillaries of the subepidermal respiratory bed is presented.

Animals↗
PubMed1979

Light and scanning microscopy of the tongue and its gustatory organs in the common toad, Bufo bufo (L.).

Unlike frogs and European tree frogs, the common toad Bufo bufo possesses a tongue lacking filiform papillae on its dorsal surface. Instead, the mucosal epithelium forms irregular, high folds, dividing the surface of the tongue into numerous separate compartments. At the bottom of those compartments occur openings of tubular glands and singular ciliated cells. In a strongly distended tongue the folds of mucosa disappear, and the regions of glandular orifices assume a shape of pocket-like recesses. The taste discs with an average diameter of 120 micrograms are localized on the top of markedly shortened fungiform papillae. The superficial layer of taste discs contains a single type of glandular supporting cells, which in part of discs show features suggesting their gradual dezintegration, probably related to the process of cellular turnover in gustatory organs.

Animals↗
PubMed1979

Light and scanning microscopy of the taste organs and vascularization of the tongue of the spotted salamander, Salamandra salamandra (L.).

The mucosa of the spotted salamander tongue and its taste organs were investigated by means of light and scanning electron microscopy. The most striking feature of the salamander tongue is an almost complete lack of papillae which are replaced by long, radially disposed folds with linear arrays of taste organs along their ridges. In respect of morphology, the taste organs of the salamander occupy an intermediate position between the taste buds of Urodela and taste discs of Salientia. Scanning electron microscopic examination of microcorrosion casts of the blood vessels of the tongue has revealed that the structure of subepidermal capillary network reflects the topography of the tongue surface and the distribution of its taste organs. In the core regions of the folds the capillary loops accompanying gustatory receptors empty via their shorter, descending arms into the draining vessels, the initial segments of which retain a course parallel to that of the folds. In the few fungiform papillae the capillary vessels form single loops whose distal ends come to lie in the vicinity of taste discs.

Animals↗
PubMed1978

Model of skin vascularization in Rana esculenta L.: scanning electron microscopy of microcorrosion casts.

Microcorrosion casts of blood vessels in the skin of Rana esculenta L. were examined by means of scanning electron microscopy with particular reference to the subepidermal network of respiratory capillaries. Due to the fact that arteries and veins lie in the deeper layers of the stratum spongiosum of the corium, the respiratory vessels form a morphologically homogeneous network. Functionally, however, this network is subdivided into small areas with a centripetal direction of blood flow. The deep capillary net, situated at the base of the stratum compactum of the corium, is not so dense as the respiratory network and does not directly communicate with it. Alveolar glands of the skin have no effect on the distribution of capillaries in the two networks.

Animals↗
PubMed1977

Fine structure of capillaries in the conus papillaris of the limbless lizard, Ophisaurus apodus (anguidae, lacertilia).

The conus papillaris of Ophisaurus apodus consists of blood vessels and pigment cells. The capillary walls are formed by endothelial cells, scarce pericytes and basal laminae. The cell bodies are attenuated and the plasmalemma of their luminal and abluminal surfaces forms microvilli. The perivascular space is well developed, containing nerve fibers and their terminals. Similar localization and ultrastructure of avian pecten oculi and lacertilian conus papillaris suggest homology of these structures.

Animals↗
PubMed1975

Hypothalamo-neurohypophysial complex in leukemia L 1210-bearing mice.

Mice of the DBA strain were inoculated with 4.5 x 10(6) L1210 ascites cells and the time response of the hypothalamo-neurohypophysial complex was studied. The amount of neurosecretory material was determined in the neuroendocrine cells of supraoptic and paraventricular nuclei, throughout the hypothalamo-neurohypophysial tract and in the neural lobe of the hypophysis. Three methods of response evaluation were employed: the amoount of neurosecretory material was estimated according to an arbitrary scale, by cytophotometry while for the hypothalamic cell-nuclei the karyometric method was used. The existence of a functional interrelation between the presence of leukemic cells and the activity of the hormonogenic sites in the hypothalamus is suggested. A clear response to the tumor inoculation was established both in the amount of stainable substance and in the nuclear volume of the secretory neurones. It is suggested that an accelerated synthesis and release of neurosecretory material in tumor recipient mice reduces renal excretion in order to compensate a dehydration caused by the production of ascitic fluid.

Animals↗