Laser-assisted removal of a feline eosinophilic granuloma from the back of the tongue

Recently, an increase in the occurrence of oral diseases in cats has been observed. Symptoms vary from case to case, but loss of appetite or fastidiousness can almost always be noted. Proliferative inflammatory eosinophilic granulomatosis is a common disease in cats, which may be localised to the skin, the mucocutaneous junctions or the oral cavity. The disease has three different manifestations: indolent cellular ulcer, eosinophilic plaque, and eosinophilic granuloma. The last mentioned form predominantly affects the medial surface of the thigh, the cheek, the tongue and the palate. Pain is not common, the lesion is nonpruritic if localised to the skin, but the nodular form in the oral cavity may make deglutition difficult. In this case, a 10.5-year-old cat was presented in poor condition due to feeding problems. Examination revealed a mass of unknown origin with macroscopically tumorous appearance, localised to the pharyngeal part of the tongue, which made swallowing and voluntary feeding difficult. The granuloma was removed by laser-assisted surgery. After adequate preparation, a LASER diode with 6-10 W output power was used, set to continuous constant-amplitude output (CW) running in a 0.6 mm optic fibre to the site of interest. The removed tissue was examined for pathomorphological features: haematoxylin and eosin, Giemsa, Azan and PAS stainings were performed to aid diagnosis. After surgery the cat recovered fast on steroids, and its condition and quality of life improved greatly. The traditional surgical technique was inapplicable due to the heavy vasculature and corresponding bleeding of the tongue.

Cutaneous mast cell tumour within a lipoma in a boxer

This report describes a case of a canine cutaneous grade I mast cell tumour which developed within a lipoma in the right axillar region of an 8-year-old male Boxer. Immunohistologically, the neoplastic mast cells were positive for serotonin, CD45 vimentin and p53, and negative for lysozyme, CD3 and CD79a expression. The proliferation index of the mast cell tumour based on the Ki-67 antigen was 6.1%. Between the benign neoplastic lipocytes and mastocytoma tumour cells intratumoural microvessels were detected by immunohistochemical staining using CD31 and claudin-5 as markers for vascular endothelium.

Secondary tumoural valvulopathy in a dog

This short report describes a case of tricuspid valvular metastasis of canine disseminated histiocytic sarcoma in a 9-year-old female Rottweiler. Immunohistochemically the malignant neoplastic cells gave a strong reaction for vimentin and lysozyme, and showed negativity for serotonin, CD3, CD79a and cytokeratin. The intratumoural microvessels were detected by immunohistochemistry using CD31 and claudin-5. This appears to be the first report of a valvular metastasis of canine malignant histiocytosis.

Evaluation of microvessel density (MVD) in canine mammary tumours by quantitative immunohistochemistry of the claudin-5 molecule

In our recent investigation, angiogenesis was evaluated and quantified by immunohistochemical evaluation of microvessel density (MVD) using claudin-5 (CLDN-5) as a marker for vascular endothelium in 67 canine mammary gland tumours. Computer image analysis was used to measure the intratumoural MVD. Higher intratumoural MVD was detected in malignant simple neoplasms compared with benign tumours. Furthermore, the results of MVD were correlated with histological grade, higher grades being accompanied by higher MVD. In simple adenomas and grade I tubular-tubulopapillary simple carcinomas the intratumoural microvessels were wide and regular in shape with evident erythrocytes in their lumen. In grade III solid carcinomas the microvessels were smaller, less regular and had irregular shape, often without a distinct lumen, and isolated endothelial cells were frequently present. In the complex carcinomas MVD was low and the intratumoural microvessels were mostly irregular in shape without a distinct lumen. The evaluation of MVD by CLDN-5 immunohistochemistry may give useful additional information on the angiogenic potential of breast cancers in dogs.

Expression and localisation of claudin-1, -2, -3, -4, -5, -7 and -10 proteins in the normal canine mammary gland

The recently identified claudins are dominant components of tight junctions, responsible for cell adhesion, polarity and paracellular permeability. Certain claudins have been shown to have relevance in tumour development. The aim of the present study was to analyse the expression of claudin-1, -2, -3, -4, -5, -7 and -10 in normal canine mammary glands. Samples from the inguinal mammary regions of 20 non-castrated, 1-13 years old female dogs were studied. Immunohistochemical analysis was performed on conventional specimens and tissue microarrays. The results of the immunohistochemical reactions detecting claudins in tissue sections were photodocumented. The immunoreactivity of claudins was quantitatively analysed on digital images using Leica QWin morphometry software. Intense membranous immunolabelling was found for claudin-1, -3 and -7, intense membranous with non-granular cytoplasmic immunolabelling for claudin-2, moderate membranous immunolabelling for claudin-4 and -5, and weak membranous immunolabelling for claudin-10. The occurrence of tight junctions was confirmed by ultrathin section electron microscopy. The available data suggested that claudins might be proteins preserved throughout the evolution of mammals. The results of our study support the concept that they are indeed preserved, since the same type of claudins, in identical distribution, could be detected in our canine mammary tissue samples as could be found in human mammary tissue.

Concentration- and time-dependent effect of aminooxyacetic acid on cortical epileptogenicity

In the present electrophysiological study the effect of aminooxyacetic acid (AOAA) on the cortical epileptogenicity, and on the basic electro-cortical activity was investigated in anesthetized rats. AOAA did not induce spontaneous epileptiform discharges but modified the somato-sensory evoked responses and the cortical epileptogenicity (induced by 4-aminopyridine) in the same manner depending on its concentration. AOAA at low concentrations increased the amplitude of evoked responses and the ipsilateral manifestation of epileptiform activity, however, at high concentrations significantly suppressed both the evoked responses and the induction and expression of seizures discharges. The anticonvulsive effect of AOAA was time-dependent (reached its maximum after 2h AOAA pre-treatment) and reversible. AOAA at low concentrations probably increases the efficacy of the NMDA excitatory system and decreases GABA-synthesis, resulting neuronal hyperexcitation. However, AOAA at high concentrations can lead to an effective cortical inhibition through intra- and extracellular accumulation of GABA. The gradual GABA accumulation - up to a certain level - at the synapses could also explain the time-dependency of the anticonvulsive effect of AOAA.

Anticonvulsive effect of AMPA receptor antagonist GYKI 52466 on 4-aminopyridine-induced cortical ictal activity in rat

The effect of GYKI-52466 (1-(4-aminophenyl)-4-methyl-7,8-methylenedioxy-5H-2,3-benzodiazepine), a selective antagonist of AMPA receptor was investigated on the generation and manifestation of 4-aminopyridine-induced cortical epileptiform activity. In vivo experiments were carried out on pentobarbital-anaesthetised adult rats. Ictal epileptiform activity was induced by local application of 4-aminopyridine (4-Ap) to the surface of somatosensory cortex. In one group of animals, GYKI 52466 was administered intraperitoneally before 4-Ap application, in another group, the already active primary focus was treated locally by GYKI 52466. Different parameters of epileptic activity were measured and compared in GYKI 52466-treated and control animals. The results demonstrate that GYKI 52466 exerts anticonvulsive effects on both the induction and the expression of epileptiform activity, by delaying the onset of the first ictal event, decreasing the numbers and duration of ictal periods, as well as the amplitudes of epileptiform discharges both in the primary and mirror foci. However, seizure propagation to other cortical areas seemed to be facilitated. The anticonvulsive effect of GYKI 52466 was stronger in pretreatment than in treatment of ongoing epileptiform activity. As a conclusion, it is supposed that AMPA receptors are probably more dominant in the induction of epileptiform activity than in the maintenance of it, mainly through the activation of corticothalamo-cortical networks. It is also supposed that the cortical inhibition which blocks the propagation of epileptiform process might be activated mainly through non-N-methyl-D-aspartate receptors.

The anticonvulsive effect of non-NMDA antagonist GYKI 52466 on 3-aminopyridine-induced primary and secondary cortical ictal activity in rat

The effect of GYKI 52466, a selective, non-competitive antagonist of the AMPA glutamate receptor subtype was investigated on the development, expression and propagation of 3-aminopyridine-induced cortical ictal activity, both in the primary and secondary focus. In one group of animals GYKI 52466 was administered intraperitoneally, 20 minutes prior to the local application of the convulsant the surface of the cortex of anaesthetized rats. Control animals were injected by physiological solution. Different parameters of electrographic ictal discharges were measured under the influence of the antagonist and compared to control values. The results demonstrate that GYKI 52466 exerts anticonvulsive effects on both the induction and the expression of primary and secondary electrical ictal activity, by delaying the onset of the first ictal period, shortening the duration of ictal activity and decreasing the amplitudes of epileptiform discharges. However, the seizure propagation was not influenced significantly. It is suggested that the initiation, maintenance and the propagation of spontaneous seizures may be controlled by separate mechanisms and that changes can occur in one of the procedures without parallel changes in others. The observations of the present study extend those reported previously by others, namely that activation of non-NMDA receptors is significantly involved in the initiation and maintenance of cortical epileptiform activity.

Chronic low-dose maternal exposure to methylmercury enhances epileptogenicity in developing rats

Effects of continuous low-dose maternal methylmercury intoxication on the induction and propagation of ictal epileptiform activity induced by 3-aminopyridine, were investigated on the neocortex of 4-weeks-old offspring rats. Epileptogenicity was significantly increased in offspring of mercury-treated animals compared to those of controls, characterized by more frequent occurrence of periodic ictal activity, a facilitated propagation of epileptiform discharges and a strong tendency to generalization. The latency of first ictal event was slightly shorter and the average duration of individual ictal periods slightly longer in treated animals. However, the amplitude of seizure discharges was significantly smaller in treated animals than in controls. We conclude, that the synaptic and membrane mechanisms responsible for initiation and propagation of paroxysmal activity were probably facilitated, while the efficacy of cortical inhibition, in preventing initiation and spread of epileptiform discharges was reduced by mercury treatment in the developing nervous system. The smaller amplitude of paroxysmal discharges could be a sign of a remarkable loss of cortical neurons.

[Effect of somatostatin-octreotide on secretion of adrenocorticotropin, cortisol and neuro-hypophyseal hormones in acromegaly]

The present work was aimed at studying the combined effects of somatostatin and corticotropin releasing hormone on the activities of the pituitary-adrenocortical axis and neurohypophysis. Patients with active acromegaly were intravenously injected with a 100 micrograms human corticotropin releasing hormone bolus before and after a 3-month subcutaneous treatment with somatostatin-octreotide (SMS 201 995; Sandostatin; 200 micrograms t. i. d.). When the Sandostatin effect was investigated, corticotropin releasing hormone test was started 2 hrs after its first daily dose. Peripheral venous blood samples were taken before and 20, 60, 90 and 120 min after the corticotropin releasing hormone load. Plasma corticotropin, arginine-8-vasopressin and oxytocin were measured by radioimmunoassay, and serum cortisol by fluorimetry. In healthy subjects, corticotropin releasing hormone stimulus elicited increases of plasma corticotropin, serum cortisol, plasma arginine-8-vasopressin and oxytocin levels by 186, 41, 178 and 58 per cent, respectively. Untreated acromegalics exhibited missing arginine-8-vasopressin, blunted corticotropin, and normal oxytocin and cortisol responses. Sandostatin therapy improved the arginine-8-vasopressin reaction, suppressed the basal levels of corticotropin and cortisol with the maintenance of cortisol stimulability; the peak-reaction of corticotropin became normal in two patients, however, with a shortened duration of response. Diuresis of the patients increased under the treatment. Sandostatin markedly alleviated the clinical symptoms and suppressed the growth hormone secretion, but did not influence the size of the pituitary adenomas. Among other factors, the alterations of growth hormone and cortisol may be hypothesized to take part in the changes of the corticotroph and neurohypophysial functions.

Screening for in vitro shoot-forming capacity of seedling explants in bell pepper (Capsicum annuum L.) genotypes and efficient plant regeneration using thidiazuron

In vitro shoot regeneration ability of 17 (7 Italian and 10 Hungarian) bell pepper genotypes was investigated using excised cotyledons and rooted hypocotyls as explants. Most of the Italian genotypes and two of the Hungarian genotypes responded well, producing shoots from rooted hypocotyls. Only two genotypes (one Italian and one Hungarian) gave a weak response using cotyledons. For direct shoot induction in these explants, in addition to the methods cited in the relevant papers, a new method was applied using thidiazuron as a cytokinin. Shoots were successfully regenerated from cotyledons of two Italian and two Hungarian genotypes using thidiazuron which were considered to be non responsive to the usual methods.

Differential effect of desglycinamide9-(Arg8)-vasopressin on cognitive functions of diabetes insipidus and alcoholic patients

Intranasal treatment with desglycinamide9-(Arg8)-vasopressin (DGAVP) improved certain aspects of cognitive functions of patients with acquired and congenital diabetes insipidus and of alcoholic patients with mild cognitive impairments. Patients with Korsakoff's syndrome, presenting with severe cognitive impairments, were resistent to DGVP treatment. DGAVP treatment did not affect blood pressure and water metabolism. The action of DGAVP on cognitive functions is probably mediated by centrally located target sites and may be expressed only in patients in whom these target sites are unimpaired.

Lack of effect of desglycinamide-arginine-vasopressin (DGAVP) on memory in patients with korsakoff's syndrome

The effect of desglycinamide9-[Arg8]-vasopressin (DGAVP) on memory processes was studied in patients with Korsakoff's syndrome. Intranasal treatment with DGAVP for 7 days affected neither attention nor short- and long-term memories. It is suggested that treatment with DGAVP is not indicated for all types of memory disorders, and that the beneficial effect of this treatment may depend on the integrity of certain brain structures.

Effects of lysine-vasopressin and 1-deamino-8-D-arginine-vasopressin on memory in healthy individuals and diabetes insipidus patients

Central diabetes insipidus (DI) patients showed impairments in short- and long-term memory functions, but not in attention and concentration, as compared to healthy individuals. A single i.m. injection or sub-chronic intranasal administration of either lysine-vasopressin (LVP) or 1-deamino-8-D-arginine-vasopressin (DDAVP) normalized the disturbed memory functions in DI patients. These peptides also improved memory functions in healthy individuals.