A novel 3-(4,5-diphenyl-1,3-oxazol-2-yl)propanal oxime compound is a potent Transient Receptor Potential Ankyrin 1 and Vanilloid 1 (TRPA1 and V1) receptor antagonist.

Transient Receptor Potential Ankyrin 1 and Vanilloid 1 (TRPA1, TRPV1) ion channels expressed on nociceptive primary sensory neurons are important regulators of pain and inflammation. TRPA1 is activated by several inflammatory mediators including formaldehyde and methylglyoxal that are products of the semicarbazide-sensitive amine-oxidase enzyme (SSAO). SZV-1287 is a new 3-(4,5-diphenyl-1,3-oxazol-2-yl)propanal oxime SSAO inhibitor, its chemical structure is similar to other oxime derivatives described as TRPA1 antagonists. Therefore, we investigated its effects on TRPA1 and TRPV1 receptor activation on the cell bodies and peripheral terminals of primary sensory neurons and TRPA1 or TRPV1 receptor-expressing cell lines. Calcium influx in response to the TRPA1 agonist allyl-isothiocyanate (AITC) (200 µM) and the TRPV1 stimulator capsaicin (330 nM) in rat trigeminal neurons or TRPA1 and TRPV1 receptor-expressing cell lines was measured by microfluorimetry or radioactive (45)Ca(2+) uptake experiments. Calcitonin gene-related peptide (CGRP) release as the indicator of 100 µM AITC - or 100 nM capsaicin-induced peripheral sensory nerve terminal activation was measured by radioimmunoassay. SZV-1287 (100, 500 and 1000 nM) exerted a concentration-dependent significant inhibition on both AITC- and capsaicin-evoked calcium influx in trigeminal neurons and TRPA1 or TRPV1 receptor-expressing cell lines. It also significantly inhibited the TRPA1, but not the TRPV1 activation-induced CGRP release from the peripheral sensory nerve endings in a concentration-dependent manner. In contrast, the reference SSAO inhibitor LJP 1207 with a different structure had no effect on TRPA1 or TRPV1 activation in either model system. This is the first evidence that our novel oxime compound SZV-1287 originally developed as a SSAO inhibitor has a potent dual antagonistic action on TRPA1 and TRPV1 ion channels on primary sensory neurons.

Stimulatory effect of pituitary adenylate cyclase-activating polypeptide 6-38, M65 and vasoactive intestinal polypeptide 6-28 on trigeminal sensory neurons.

Pituitary adenylate cyclase-activating polypeptide (PACAP) acts on G protein-coupled receptors: the specific PAC1 and VPAC1/VPAC2 receptors. PACAP6-38 was described as a potent PAC1/VPAC2 antagonist in several models, but recent studies reported its agonistic behaviors proposing novel receptorial mechanisms. Since PACAP in migraine is an important research tool, we investigated the effect of PACAP and its peptide fragments on trigeminal primary sensory neurons. Effect of the peptides was studied with ratiometric Ca-imaging technique using the fluorescent indicator fura-2 AM on primary cultures of rat and mouse trigeminal ganglia (TRGs) neurons. Specificity testing was performed on PAC1, VPAC1 and VPAC2 receptor-expressing cell lines with both fluorescent and radioactive Ca-uptake methods. Slowly increasing intracellular free calcium concentration [Ca(2+)]i was detected after PACAP1-38, PACAP1-27, vasoactive intestinal polypeptide (VIP) and the selective PAC1 receptor agonist maxadilan administration on TRG neurons, but interestingly, PACAP6-38, VIP6-28 and the PAC1 receptor antagonist M65 also caused similar activation. The VPAC2 receptor agonist BAY 55-9837 induced similar activation, while the VPAC1 receptor agonist Ala(11,22,28)VIP had no significant effect on [Ca(2+)]i. It was proven that the Ca(2+)-influx originated from intracellular stores using radioactive calcium-45 uptake experiment and Ca-free solution. On the specific receptor-expressing cell lines the antagonists inhibited the stimulating actions of the respective agonists, but had no effects by themselves. PACAP6-38, M65 and VIP6-28, which were described as antagonists in numerous studies in several model systems, act as agonists on TRG primary sensory neurons. Currently unknown receptors or splice variants linked to distinct signal transduction pathways might explain these differences.

Isolation of chicken anaemia virus from broiler chickens.

Chicken anaemia virus (CAV) infection was demonstrated, by both serology and virus isolation, in 1- to 6-week-old broiler chickens originated from various parent flocks in Hungary. Total losses in the broiler flocks were estimated at 7 to 8% and about 25% of the chickens failed to reach target body mass by the 7th week of life. The clinical signs, postmortem lesions and histopathological changes of the affected chickens were similar to those of naturally occurring CAV-induced infectious anaemia of young chickens. In MDCC-MSB1 cell cultures, a chloroform-resistant virus smaller than 50 nm in diameter, resistant to heating at 70 degrees C for 30 min, and antigenically very closely related to the Cux-1 strain of CAV was isolated from the liver of naturally diseased broilers. This virus isolate was designated the Bia strain of CAV. Inoculation of susceptible 1-day-old SPF chicks with a CAV-positive liver extract from naturally diseased broilers caused pathological changes characteristic of CAV infection, namely impaired growth, severe anaemia with atrophy of the bone marrow, marked atrophy of the lymphoid organs and petechial haemorrhages throughout the body. A quite similar pathological syndrome was also induced by inoculation of 1-day-old SPF chicks with the MDCC-MSB1 cell-culture-propagated new Bia strain of CAV. The CAV was successfully reisolated from the livers of experimentally inoculated birds, and antibodies to the reference Cux-1 strain of CAV were also demonstrated by the indirect immunofluorescence test in sera of naturally diseased and experimentally inoculated chickens. No antibodies were found against infectious bursal disease virus, reticuloendotheliosis virus, Marek's disease herpesvirus as well as avian adenoviruses and reoviruses. The reported disease of young broiler chickens was associated with natural infection of a new isolate of CAV. On the basis of its physicochemical, antigenic and pathogenic characteristics, this virus is similar to other strains of CAV isolated from chickens in other countries.

Pathological and immunological study of goose embryos experimentally infected with duck plague virus.

A total of 240 embryonated goose eggs obtained from two susceptible flocks were used. Half of the eggs were inoculated into the allantoic cavity with a virulent strain (7593) of duck plague virus isolated from an acute outbreak, and the other half were inoculated with the attenuated vaccine virus (KAPEVAC). Ten, 100 or 1000 CPU/0.1 ml virus were given on days 12 and 20 of incubation. Embryos that died and surviving embryos killed at 5-day intervals were examined by light and electron microscopy. The yolk and the serum of embryos that survived until hatching were assayed for antibody content. Lymphocytes separated from the blood were used for the immuno-rosette formation and lymphocyte stimulation tests. Pathomorphological changes indicative of virus replication occurred in the liver, kidney, myocardium, gizzard muscle and chorioallantoic membrane (CAM) of the embryos in the case of both virus strains. The time of onset and severity of these changes and the time and rate of embryonic mortality depended on the virulence of the strain used for inoculation, the virus dose and the time of inoculation. Virus-neutralizing (VN) antibodies were demonstrable neither in the yolk nor in the serum of goslings exsanguinated after hatching. The lymphocytes recognized the virus antigen in the in vitro cellular tests and responded to it with blastogenic transformation. As opposed to adult birds, in the embryos duck plague virus infection did not cause damage to the digestive tract mucosa and the lymphoid organs.

Aujeszky's disease of sheep: experimental studies on the excretion and horizontal transmission of the virus.

Five 5-month-old merino lambs were nasally inoculated with 10(5.0) TCID50 of Aujeszky's disease virus (ADV). The dynamics of virus excretion in the nasal discharges--in agreement with the histologic findings--indicated that ADV also replicates in extraneural sites, in the upper and lower parts of the respiratory tract. The virus was excreted continuously in the nasal discharges, even during the incubation period. The titres, with certain fluctuations, increased gradually up to the final stage of the fatal disease. Following the onset of the clinical disease, the titre of excreted virus (ranging from 10(4.0) to 10(6.0) TCID50/0.1 ml) was comparable with the ADV content found in the nasal discharge of naturally infected piglets. However, the horizontal transmission of ADV to contact lambs failed.

Antigenic and biological characterisation of avian paramyxovirus type I isolates from pigeons--an international collaborative study.

During 1981-1983 a disease of pigeons (Columba livia), characterised predominantly by nervous signs, spread across Europe. In the present study 57 viruses isolated from pigeons from 15 countries (12 European, Japan, Israel and Sudan) were characterised. All were shown to be avian paramyxoviruses of the A/PMV-1 serotype. Monoclonal antibody binding tests showed 53 of the viruses to be identical. The virus from Sudan was similar to these viruses but showed distinguishable variation. One vaccinal virus from France and two virulent viruses from Czechoslovakia were unrelated to the other pigeon A/PMV-1 isolates.

Lymphoreticular tumour in pen-raised pheasants associated with a reticuloendotheliosis like virus infection.

An outbreak of a lymphoproliferative disease in pheasants is described. Nodular or diffuse tumours were found on the head and in various internal organs. The lesions consisted of undifferentiated lymphoreticular cells. A typical C-type virus, similar to reticuloendotheliosis virus was isolated in tissue culture. However, this virus particle could not be seen in the tumours. The isolate is antigenically related to the reticuloendotheliosis group of viruses. Typical reticuloendotheliosis was induced by tumour and spleen cells from a field case in both young pheasants and chickens. Antibodies to the reticuloendotheliosis virus group were demonstrated in serum samples from naturally diseased and experimentally infected birds. The virus could be re-isolated from experimentally infected birds in tissue culture. Serological and virological evidence indicate that Marek's disease virus and avian leukosis viruses of subgroup A, B, C and D were not involved in the induction of the lymphoproliferative disease in pheasants.