Method for quantifying the Pasteurella multocida antigen adsorbed on aluminum hydroxide adjuvant in swine atrophic rhinitis vaccine.

Swine atrophic rhinitis is a disease caused by Pasteurella multocida and Bordetella bronchiseptica that affects pigs. Inactivated vaccines containing the toxins produced by Pasteurella multocida and Bordetella bronchiseptica have been widely used for the prevention of swine atrophic rhinitis. The efficacy of a vaccine is correlated with the amount of antigen present; however, the protective toxin of P. multocida bound to aluminum hydroxide, which is used as an adjuvant, can hinder the monitoring of the antigen concentration in the vaccine. This study assessed the applicability of a dot immunoassay as an antigen quantification method using monoclonal antibodies. This quantification method was able to detect the antigen with high specificity and sensitivity even when the antigen was bound to the adjuvant, and its application to vaccine products revealed a correlation between the amount of antigen present in the vaccine and the neutralizing antibody titers induced in pigs. The antigen quantification method presented in this study is a simple and sensitive assay capable of quantifying the amount of antigen present in a vaccine that can be used as an alternative quality control measure.

Development of a genetically modified nontoxigenic Pasteurella multocida toxin as a candidate for use in vaccines against progressive atrophic rhinitis in pigs.

OBJECTIVE: To construct a genetically modified nontoxigenic Pasteurella multocida toxin (PMT) and examine its immunoprotective activity against challenge exposure with wild-type PMT in pigs. ANIMALS: 5 healthy pigs. PROCEDURE: A nontoxigenic PMT was created by replacing the serine at position 1164 with alanine (S1164A) and the cysteine at position 1165 with serine (C1165S). Toxic activity was determined by use of the guinea pig skin test and mouse lethality test. Three pigs were vaccinated twice with the modified PMT, and the remaining 2 pigs served as nonvaccinated control animals. Vaccinated and control pigs were challenge exposed with wild-type PMT. Pigs were euthanatized and necropsied on day 14 after challenge exposure. Turbinate atrophy was examined macroscopically and assigned a score. Serum anti-PMT antibodies were determined by use of an ELISA. RESULTS: The genetically modified PMT was characterized by a total lack of toxic activity. Pigs vaccinated with the modified PMT became seropositive; in contrast, control pigs remained seronegative. Necropsy revealed that the 2 control pigs had moderate and severe turbinate atrophy, respectively, whereas the 3 vaccinated pigs did not have any lesions in the turbinates or abnormalities in other organs. CONCLUSIONS AND CLINICAL RELEVANCE: Modification by use of S1164A and C1165S leads to a complete loss of toxic effects of PMT without impairment of the ability to induce protective immunity in pigs. Analysis of these results suggests that genetically modified PMT may represent a good candidate for use in developing a vaccine against progressive atrophic rhinitis in pigs.

In vitro study of the immune stimulating activity of an atrophic [correction of athrophic] rhinitis vaccine associated to chitosan microspheres.

Chitosan microspheres (CMs) were prepared by an ionic gelation process with tripolyphosphate and characterized. Bordetella Bronchiseptica Dermonecrotoxin (BBD), a major virulence factor of a causative agent of atrophic rhinitis (AR), was loaded on to the CMs for nasal vaccination. BBD-loaded CMs were observed as aggregated shapes although unloaded CMs were observed as relatively spherical ones. The average particle size of the BBD-loaded CMs was 4.39 microm. The lower the molecular weight of chitosan and the higher the medium pH, the greater was the release of BBD from the BBD-loaded CMs in vitro due to weaker intermolecular interaction between chitosan and BBD. Tumor necrosis factor alpha and nitric oxide from RAW264.7 cells exposed to BBD-loaded CMs were gradually secreted with time, suggesting that released BBD from CMs had immune stimulating activity of AR vaccine in vitro.

Turbinectomia parcial inferior versus cauterização submucosa para hipertrofia da concha nasal inferior / Parcial inferior turbinecomy versus submucosal cauterization os hipertrophic inferior turbinate

Obstrução nasal é a queixa crônica mais encontrada pelo otorrinolaringologista. A maioria responde ao tratamento clínico, mas em alguns casos a cirurgia é necessária. Não há consenso sobre qua técnica deve ser empregada.

Immune responses of piglets to Pasteurella multocida toxin and toxoid.

Experimental atrophic rhinitis (AR), serum antibody titres and in vitro lymphoproliferation to Pasteurella multocida derived toxin (Pm-T) were studied in piglets. Specific immune responses to Pm-T and Pm-T induced conchae atrophy were compared with AR immunity. This immunity was initiated by the Nobi-VAC AR-T vaccine administered at various times with respect to Pm-T challenge. Animals challenged with Pm-T developed conchae atrophy, but no antibodies nor cellular immune responses to Pm-T were detected. Vaccination 3 weeks before Pm-T challenge protected pigs against breakdown of nasal bony tissues. This protection was accompanied by an increase of serum antibodies and in vitro lymphoproliferation to Pm-T. Animals vaccinated 10 days before or after Pm-T challenge also had antibodies and cellular immune responses. However, these animals developed AR. In vitro, Pm-T appeared mitogenic for quiescent (non-immune) peripheral lymphocytes and Concanavalin A stimulated lymphocytes from some pigs. These in vitro lymphoproliferative responses could be partly abrogated by the addition of monomorphic anti-swine major histocompatibility complex class II DQ and DR specific monoclonal antibodies. We conclude that Pm-T is poorly immunogenic in vivo and does not initiate a protective Pm-T specific immune response. Pigs were protected from AR by vaccination, but protection was dependent on the timing of vaccine administration. We speculate that Pm-T modifies the immune response such that the response is not directed towards the toxin but to an unidentified component in the nose of piglets.

Vacinaçäo com Bordetella bronchiseptica e Pasteurella multocida, associada a alteraçöes do manejo, no controle da rinite atrófica dos suínos / Use of a Bordetella bronchiseptica-Pasteurella multocida vaccine in addition to improved management, to control swine atrophic rhinitis

Empregou-se uma vacina preparada com B. bronchiseptica e P. multocida tipo D, toxigênica, para controlar a rinite atrófica em rebanho de 220 matrizes suínas. Aproximadamente 60 por cento dos animais em idade de abate exibiam sinais clínicos da doença antes da vacinaçäo. Lesöes das conchas nasais foram observadas em 70 por cento (56/80) dos animais antes do período experimental e em 77 por cento (55/71) dos näo vacinados, examinados ao final do experimento. O rebanho foi acompanhado durante 12 meses antes e 22 meses após o início da vacinaçäo. Realizaram-se alteraçöes no manejo, reduçäo do plantel de 220 para 180 matrizes e mudanças no esquema de limpeza, desinfecçäo e ocupaçäo dos prédios. As medidas adotadas eliminaram a doença clínica dos leitöes jovens e reduziram (P<0,001) as alteraçöes das conchas nasais, observadas em apenas 15 por cento (39/266) dos leitöes vacinados, a ocorrência de pneumonias e pleuropneumonias, de 22 por cento para 9 por cento dos animais necropsiados e o número de condenados no frigorífico, 11 por cento para 0,8 por cento

[Toxicological considerations in the evaluation of veterinary drugs]. / Toxicologische overwegingen bij de beoordeling van diergeneesmiddelen.

Interactions between veterinary pharmacotherapy, toxicology of residues, prevention of residues of veterinary drugs and the evaluation of veterinary drug files are discussed on the basis of a number of examples. Sulphadimidine is used to treat atrophic rhinitis in medicated feeds which do not benefit the animal but are the cause of persistent sulphonamide residues in feed mills and husbandry. Carbadox is a potentially effective prophylactic feed additive for the prevention of swine dysentery, but is mostly used in high dosages which are almost toxic for the animals, and used during unnecessary prolonged periods. It is also prescribed as a therapeutic agent in which case a symptom of poisoning, dry faeces, is mistaken for a sign of recovery. Carbadox and/or its metabolites are carcinogenic and its use should be restricted to a bare minimum. Furazolidone is an example of an effective veterinary drug, the use of which should be limited by the fact that detoxification mechanisms of the animals, may result in the appearance of reactive metabolites which are available in the gastro-intestinal tract of the consumer. The central issue in a 'minimal residue' policy regarding the use of veterinary drugs should be the selection of effective drugs. Such a selection could result in a significant reduction of the incidence of veterinary drug residues. Second to this issue is the question of the extent to which residue toxicology should modulate the use of veterinary drugs.

Rinitis atrófica: ocena aspectos medico sociales / Athrophic rhinitis: ozena medical social aspects

La rinitis atrófica: oceana es una rinitis crónica, con características clínico-patológicas bien definidas, de incidencia significativa en nuestro medio. Se presenta predominantemente en pacientes de sexo femenino y en etapa de vida sexual activa, por su indudable relación hormonal en la patogenia de esta entidad. Se ha realizado un estudio exhaustivo de 50 casos que se han presentado en el Hospital Loayza durante los últimos 10 años. Se han confeccionado cuadros ilustrativos, distribuyéndolos por grupos etáreos, lugar de nacimiento, procedencia, el tiempo de enfermedad, ocupación, estado civil, uni o bilateralidad de la afección, sintomatología, cuadro clínico, exámenes complementarios, tratamiento médico y quirúrgico, y resultados del tratamiento. Se describe la técnica de Eyries modificada que es la que mejores resultados ofrece a los pacientes. Es sumamente importante su diagnóstico precoz y la aplicación del tratamiento adecuado, así como las medidas preventivas para evitar su propagación y la gran repercusión sicosocial en los pacientes afectados

[Rhinological aspects in transseptal pituitary surgery (author's transl)]. / Rhinologische Aspekte der transseptalen Hypophysen-Chirurgie.

Ozaena used to be the most common rhinological complication following transnasal pituitary surgery. The development of subtle microsurgical techniques has significantly reduced this risk, and the transrhinoseptal approach to the pituitary fossa has become the method of choice. The surgical technique is described. 20 patients were followed up over a period of 2 to 28 months following removal of pituitary tumor. 18 patients showed normal nasal mucosa. In 2 cases there are circumscribed lesions to the nasal mucosa which might ultimately give rise to ozaena.