[Detection of Brachyspira pilosicoli and other Brachyspira species in Argentine poultry farms]. / Detección de Brachyspira pilosicoli y otras especies de Brachyspira en granjas avícolas argentinas.

Some species of the genus Brachyspira such as Brachyspira pilosicoli, Brachyspira intermedia and Brachyspira alvinipulli are pathogenic species capable of producing disease in laying hens. In our country, the presence of B. pilosicoli and other species of Brachyspira has been reported in pigs and dogs but there is no record of their presence in poultry. Fecal and cecal content samples from 34 laying hens of 4, 12 and 24 months of age from two farms were analyzed by isolation, biochemical tests and PCR. B. pilosicoli and Brachyspira spp. were identified in samples taken from laying hens of 12 and 24 months of age.

Detección de Brachyspira pilosicoli y otras especies de Brachyspira en granjas avícolas argentinas / Detection of Brachyspira pilosicoli and other Brachyspira species in Argentine poultry farms

Algunas especies del género Brachyspira, como Brachyspira pilosicoli, Brachyspira intermedia y Brachyspira alvinipulli, son especies patógenas capaces de producir enfermedad en gallinas ponedoras. En nuestro país, la presencia de B. pilosicoli y otras especies de Brachyspira ha sido informada en cerdos y en perros, pero no existen antecedentes de su presencia en aves de corral. En este estudio se analizaron muestras de materia fecal y de contenido de ciego de 34 gallinas ponedoras de 4, 12 y 24 meses provenientes de 2 establecimientos por medio del aislamiento, la realización de pruebas bioquímicas y reacción en cadena de la polimerasa. B. pilosicoli y Brachyspira spp. fueron identificadas en muestras tomadas de aves de 12 y 24 meses de edad

Some species of the genus Brachyspira such as Brachyspira pilosicoli, Brachyspira intermedia and Brachyspira alvinipulli are pathogenic species capable of producing disease in laying hens. In our country, the presence of B. pilosicoli and other species of Brachyspira has been reported in pigs and dogs but there is no record of their presence in poultry. Fecal and cecal content samples from 34 laying hens of 4, 12 and 24 months of age from two farms were analyzed by isolation, biochemical tests and PCR. B. pilosicoli and Brachyspira spp. were identified in samples taken from laying hens of 12 and 24 months of age

Biodistribution and phototherapeutic properties of Zinc (II) 2,9,16,23-tetrakis (methoxy) phthalocyanine in vivo.

Photodynamic therapy (PDT) was investigated using the phthalocyanine photosensitizer Zinc (II) 2,9,16,23-tetrakis (methoxy) phthalocyanine (ZnPc(OCH(3))(4)) on BALB/c mice. Animals bearing tumor were treated with 0.2mg/kg body weight (bw) ZnPc(OCH(3))(4) and 24h later were irradiated with 70, 140 and 210 J/cm(2) of visible light from a source delivering 39 mW/cm(2). In this study, we have tested the efficiency of ZnPc(OCH(3))(4) liposomal formulation on mice. Biodistribution studies were performed in tumor-free mice and tumor-bearing mice at various time points up to 24h after ZnPc(OCH(3))(4)-PDT treatment. The tumor sizes were evaluated over different period in parallel experiments. The maximal efficiency and selectivity of photosensitizer accumulation in tumor tissue take place at 24h after drug administration of 0.2mg/kg bw ZnPc(OCH(3))(4). In the tumor sections for biochemical studies, apoptosis was visualized by activation of caspase-3. ZnPc(OCH(3))(4)-PDT tumors showed a significant delay in growth as compared to untreated control mice. In all cases, ZnPc(OCH(3))(4)-PDT-treated tumors showed a significant regression. The results indicated a dramatic decrease of tumors size after 10 days post-irradiation with 210 J/cm(2) and no recurrence of the disease was detectable within at least 90 days. The phototherapeutic agent ZnPc(OCH(3))(4) demonstrated preferential accumulation in tumor in comparison with skin tissues, except in the case of kidney. The ratio of tumor/skin tissues ranged a value of 8. These results suggest that ZnPc(OCH(3))(4)-PDT may be of particular importance in the treatment of accessible malignancies.

Pharmacokinetic, toxicological and phototherapeutic studies of phthalocyanine ZnPcCF3.

Photodynamic therapy (PDT) is an alternative modality for cancer therapy. It induces neoplasic cells death through photoachievable sensitizers. The aim of this work was to evaluate the pharmacokinetic, toxic and phototherapeutic effects of the phthalocyanine ZnPcCF(3) in a Balb/c mice tumor model. Biodistribution studies were carried out by intraperitoneal injection of 0.2mg/kg ZnPcCF(3). Histological studies and serum biochemical parameters were used to evaluate hepatic and renal toxicity and functionality. After tumor irradiation (210J/cm(2)), an analysis of tumor necrosis degree was used to evaluate the phototherapeutic effects. It was measured at 1, 2, 3 and 4 days after PDT. Vital staining was performed by intraperitoneal injection of 0.35ml 1% Evans Blue solution. Six hours later, tumors were excised and examined. The unstained area was attributed to necrotic tissue, whereas the stained area showed tissue with preserved blood supply. ZnPcCF(3) was accumulated in spleen, liver and duodenum. It suggests that ZnPcCF(3) is eliminated from the body via bile-gut. The phthalocyanine was not found in brain, therefore, it would not cross the blood-brain barrier, thus toxicity risk in the central nervous system is not probable. Moreover, ZnPcCF(3) does not accumulate in skin, it would eliminate cutaneous photosensitizing risks. The dose of 0.2mg/kg ZnPcCF(3) resulted in a low acute toxicity with revertible damages, which indicates that this dose can be used for PDT. The tumor death was of 89% 4 days after PDT. It indicates that ZnPcCF(3) would be effective in PDT.

Respuestas de anticuerpos pasivosy efecto de la edad de los lechonesen la vacunación contra el virusde la peste porcina clásica / Passive antibodies response and effect of the age of the swine on the vaccination against classical swine fever virus

La vacunación con la cepa China es utilizada para prevenir la Peste Porcina Clásica. Pero la presencia de anticuerpos pasivos y la edad de los lechones a la vacunación pueden originar una respuesta humoral activa no satisfactoria. Se vacunaron animales de 7, 21 y 56 días de edad con y sin inmunidad pasiva. Se tomaron muestra de sangre al momento de la vacunación y a los 15 y 45 días posteriores. Los animales respondieron de distintas maneras a la vacunación, según la presencia o no de anticuerpos pasivos. Se observó que a mayor edad de vacunación, mayor era el porcentaje de animales que respondieron a la vacuna en el último muestreo. La técnica de ELISA no permitió detectar anticuerpos a los 15 días de vacunados.

The vaccination with the Chinese strain is used to prevent the Classical Swine Fever. But the presence of passive antibodies and age of piglets at the time of vaccination can originate an unsatisfactory active humoral response. In this study 7, 21 and 56 days animals with and without passive immunity, were vaccinated. Blood samples were taken at the time of vaccination and then at 15 and 45 days later. The animals responded in different ways to vaccination, according to the presence or not of passive antibodies. It was observed that as greater the age of vaccination, greater was the percentage of animals that responded to the vaccine in the last sampling. The ELISA technique did not allow detecting antibodies 15 days after vaccination.

Síndrome multisistémico de desmejoramiento posdestete (SMDP) en cerdos criados al aire libre en una granja situada en Argentina / Postweaning Multisystemic Wasting Syndrome (PMWS) in pigs reared in an outdoor system in the farm in Argentina

Se realizó un estudio clínico-patológico en cerdos criados al aire libre, estos presentaron signos de desmejoramiento y muerte entre los 40 a 90 días de vida. Durante un periodo determinado se registraronlos índices de mortalidad en las categorías de recría y levante. A un grupo de animales con signos de desmejoramiento se les extrajo sangre y se les realizó la necropsia. Se tomaron muestras de tejidos para la realización de análisis histopatológicos, inmunohistoquímicos, bacteriológicos, parasicológicos y virológicos. Los índices de mortalidad estuvieron incrementados en la primera parte del período estudiado. Los signos clínicos observados fueron: retardo en el crecimiento, pérdida de peso y muerte. A la necropsia se observó palidez de mucosas, ganglios linfáticos megálicos y friables, edema de pericardio y de cavidad abdominal. En pulmón se observó neumonía intersticial. El riñón se mostró con áreas blanquecinas en corteza y edema en pelvis. Las lesiones observadas microscópicamente fueron: depleción linfocitaria en órganos linfoides, infiltración de histiocitos, presencia de células gigantes, cuerpos de inclusión intra citoplasmáticos y necrosis multifocales. Además, tanto las células gigantes, los cuerpos de inclusión y los macrófagos de las áreas foliculares de los tejidos linfoides, se manifestaron como inmunorreactivos en la técnica del complejo abidina biotina (ABC) frente al anticuerpo monoclonal del circovirus porcino tipo II (CVP2). Estos hallazgos confirman la presencia de Síndrome de Multisistémico de Desmejoramiento Posdestete (SMDP) en cerdos criados al aire librecon cuadros clínicos patológicos similares a los descriptos en sistemas confinados.

Pharmacokinetic and phototherapeutic studies of monocationic methoxyphenylporphyrin derivative.

BACKGROUND AND OBJETIVE: Photodynamic therapy, a novel treatment for cancer, works through photoactivation of a tumor-localized photosensitive drug, and localized through oxidative damage to kill cells and ablate tumors. Pharmacokinetic and phototherapeutic properties of a cationic porphyrin were assayed in a Balb/c mouse cancer model in order to evaluate its efficiency as photosensitizer. METHODS: Biodistribution studies were carried out by intraperitoneal injection of 5mg/kg CP incorporated into a liposome solution. CP was recovered from serum and organs at various times after treatment. The serum biochemical parameters and histological studies were used to test hepatic and renal functionality. For phototherapeutic studies, the light source used was a slide projector (360J/cm(2)). The efficiency of CP was evaluated by following tumor growth curves for 10 days after PDT doses. Immunohistochemical detection was carried out to evaluate caspase-3 activation in CP-PDT-treated tumors. RESULTS AND CONCLUSIONS: The photosensitizer distribution suggests that CP is mainly eliminated from the organism via the bile-gut pathway, and that neurotoxic and cutaneous photosensitivity effects are reduced or absent. The porphyrin distribution from bloodstream to tissue began at 24h of drug administration. CP did not affect the hepatic and renal functionality, as was demonstrated by the physiological parameters. PDT-treated tumors showed delay in growth rate as compared to untreated control mice. Biochemical studies showed that the efficient tumor regression is dependent on caspase-3 activity signaling response associated with apoptosis. The results obtained suggest that the porphyrin CP may be a promising candidate for further use in PDT treatments.