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1.
Poult Sci ; 100(8): 101233, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34174568

RESUMO

Rotation with different active ingredients is among the most effective and recommended strategies to preserve the efficacy of anticoccidial drugs and reduce the emergence of resistance. Tools such as anticoccidial sensitivity tests (ASTs) are ideally used to make rational rotation programs and bring benefits to production. The objective of this study was to evaluate the sensitivity of E. acervulina (EA) and E. maxima (EM) from 3 different regions in Brazil, by using four ASTs. Feces samples weighing 6 to 7 kg were collected in the regions of São Paulo, Paraná, and Minas Gerais. Prevalent oocysts from feces were filtered, identified, and quantified to conduct 2 ASTs with EA and 2 with EM. The same experimental design was used in every AST (4 replicates per treatment, with 6 birds each, for a total of 240 birds). Treatment groups were a nonchallenged and nonmedicated control group (T1), a challenged and nonmedicated control group (T2), and the other groups challenged and treated with the following compounds: lasalocid (90 ppm - T3), maduramycin (6 ppm - T4), decoquinate (30 ppm - T5), nicarbazin+semduramicin (66 ppm - T6), monensin (110 ppm - T7), salinomycin (66 ppm - T8), narasin+nicarbazin (100 ppm - T9), and nicarbazin (125 ppm - T10). At the end of each AST (20 d), the percent change (delta value) between the treated group (T3 to T10) and the control group (T2) was calculated for the following variables: body weight gain, feed conversion ratio, lesion score, and an indicator of percentage of optimal anticoccidial activity (POAA) that included T2. Different sensitivity levels of EA and EM isolates could be identified. As a whole, drugs from T5 and T3 groups showed higher delta values when compared to other compounds, whereas the lowest sensitivity levels of these isolates were observed in groups T4 and T7. Despite some limiting factors, ASTs can be a good tool for strategic selection of anticoccidial drugs in order to maintain efficacy and extend the lifespan of these molecules.


Assuntos
Coccidiose , Coccidiostáticos , Eimeria , Preparações Farmacêuticas , Doenças das Aves Domésticas , Animais , Brasil , Galinhas , Coccidiose/tratamento farmacológico , Coccidiose/veterinária , Coccidiostáticos/farmacologia , Coccidiostáticos/uso terapêutico , Doenças das Aves Domésticas/tratamento farmacológico , Doenças das Aves Domésticas/epidemiologia
2.
J Mater Chem B ; 3(33): 6837-6846, 2015 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-32262476

RESUMO

An inorganic/organic hybrid material with a triggering mechanism for specific drug delivery at the colon was synthesized. First, hydroxyapatite nanowhiskers (n-HA) with a high aspect ratio, narrow particle size distribution and high surface area, ca. 67 m2 g-1, are prepared. As proof-of-concept, terbinafine, a fungicidal agent, was loaded onto the n-HA, obtaining a drug loading of 40.63 mg of terbinafine per gram of n-HA. Hydroxyapatite nanowhiskers loaded with terbinafine were encapsulated with chondroitin sulfate (CS) microspheres, using chemically modified glycidyl methacrylate by performing ultrasonic microemulsion polymerization. The obtained hybrid materials were characterized by TEM, SEM, FTIR, and NMR. Dispersed n-HA in CS microspheres was obtained for different n-HA contents, from 1 to 10% (w/w). In vitro studies have been carried out to investigate terbinafine release from hybrid microspheres in simulated gastric fluid and simulated intestinal fluid. The studies demonstrated that sustained drug release can be obtained using the developed hybrid material.

3.
Ars Vet. ; 36(4): 278-285, 2020. tab, graf
Artigo em Inglês | VETINDEX | ID: vti-29941

RESUMO

Marek's disease is an important neoplastic disease in birds caused by a serotype 1 specific herpesvirus; it is controlled by vaccination. In commercial breeders and layers in Brazil, current vaccination programs use the combination of attenuated or non-pathogenic strains of the HVT virus (turkey herpesvirus - serotype 3) and CVI 988 (Rispens - serotype 1). The combination of serotype 3 and 1 it has been an important and effective control strategy through the vaccination of long-lived birds. In addition, more recently the recombinant rHVT strain (vectorized vaccines) has been used in some vaccine programs. This studys main objective was to compare CVI and HVT components replication in feather tips in three different Marek's disease (MD) immunoprophylactic programs (T01 program A, T02 program B and T03 program C). Quantification of these two vaccine strains was performed by real-time PCR in samples collected at the ages of 14, 21, and 28 days. At 14 days, mean of log[cvi] in program B was significantly higher than C (p<0.05). For mean of log[hvt], at 28 days, program B was significantly higher than A (p<0.05). For proportion of positives, at 14 days, program B had 2.7 times more risk to be positive in CVI than program C (p<0.001). At 21 days, program B had 1.7 times more risk to be positive in CVI than program C (p=0.005). For HVT, at 28 days, program B had 3.2 times more risk to be positive than program A (p=0,009). Results showed significant differences between the treatments evaluated. In general the conventional combination Mareks vaccine containing CVI+HVT (program B) showed higher replication rate and percentage of vaccine coverage than the programs with rHVT vector vaccines (program A and C).(AU)


A doença de Marek é uma importante doença neoplásica das aves causada por um herpesvírus específico do sorotipo 1 e seu controle se faz por vacinação. Em reprodutoras e poedeiras comerciais do Brasil, os programas de vacinação utilizam a combinação de estirpes atenuadas ou não patogênicas do vírus HVT (turkey herpesvirus - sorotipo 3) e CVI 988 (Rispens - sorotipo 1). A combinação do sorotipo 3 e 1 tem sido uma importante e efetiva estratégia de controle para aves de vida longa. Além disso, mais recentemente a fração rHVT recombinante (vacinas vetorizadas) vem sendo utilizada em alguns programas vacinais. O objetivo deste estudo foi comparar a replicação das frações CVI e HVT no folículo da pena em três programas imunoprofiláticos distintos (T01 programa A, T02 programa B e T03 programa C). A quantificação das duas estirpes vacinais foi realizada por PCR em tempo real nas amostras colhidas nas idades de 14, 21 e 28 dias. Aos 14 dias, em média, log[cvi] do programa B foi significativamente maior do que C (p<0.05). Aos 21 e 28 dias, a média do log[cvi] do programa C foi significativamente menor do que A e B (p<0.05). Para log[hvt], aos 28 dias, a média do programa B foi significativamente maior do que A (p<0.05). Para proporção de positivos, aos 14 dias, o programa B teve 2,7 vezes mais risco de ter positivos no CVI do que C (p<0.001). Aos 21 dias, o programa B teve 1,7 vezes mais risco de ter positivos no CVI do que C (p=0.005). Para HVT, aos 28 dias, o programa B teve 3,2 vezes mais risco de ter positivos do que A (p=0,009). Os resultados obtidos evidenciam diferenças significativas entre os tratamentos. De maneira geral a vacina convencional de Marek combinada com o CVI e HVT (programa B) apresentou maior taxa de replicação, velocidade e percentual de cobertura vacinal do que os programas compostos com vacinas vetorizadas com rHVT (programa A e C).(AU)


Assuntos
Animais , Doença de Marek , Doenças das Aves Domésticas , Vacinação/veterinária , Vacinas contra Doença de Marek
4.
Ars vet ; 36(4): 278-285, 2020. tab, graf
Artigo em Inglês | VETINDEX | ID: biblio-1463561

RESUMO

Marek's disease is an important neoplastic disease in birds caused by a serotype 1 specific herpesvirus; it is controlled by vaccination. In commercial breeders and layers in Brazil, current vaccination programs use the combination of attenuated or non-pathogenic strains of the HVT virus (turkey herpesvirus - serotype 3) and CVI 988 (Rispens - serotype 1). The combination of serotype 3 and 1 it has been an important and effective control strategy through the vaccination of long-lived birds. In addition, more recently the recombinant rHVT strain (vectorized vaccines) has been used in some vaccine programs. This study’s main objective was to compare CVI and HVT components’ replication in feather tips in three different Marek's disease (MD) immunoprophylactic programs (T01 – program A, T02 – program B and T03 – program C). Quantification of these two vaccine strains was performed by real-time PCR in samples collected at the ages of 14, 21, and 28 days. At 14 days, mean of log[cvi] in program B was significantly higher than C (p<0.05). For mean of log[hvt], at 28 days, program B was significantly higher than A (p<0.05). For proportion of positives, at 14 days, program B had 2.7 times more risk to be positive in CVI than program C (p<0.001). At 21 days, program B had 1.7 times more risk to be positive in CVI than program C (p=0.005). For HVT, at 28 days, program B had 3.2 times more risk to be positive than program A (p=0,009). Results showed significant differences between the treatments evaluated. In general the conventional combination Marek’s vaccine containing CVI+HVT (program B) showed higher replication rate and percentage of vaccine coverage than the programs with rHVT vector vaccines (program A and C).


A doença de Marek é uma importante doença neoplásica das aves causada por um herpesvírus específico do sorotipo 1 e seu controle se faz por vacinação. Em reprodutoras e poedeiras comerciais do Brasil, os programas de vacinação utilizam a combinação de estirpes atenuadas ou não patogênicas do vírus HVT (turkey herpesvirus - sorotipo 3) e CVI 988 (Rispens - sorotipo 1). A combinação do sorotipo 3 e 1 tem sido uma importante e efetiva estratégia de controle para aves de vida longa. Além disso, mais recentemente a fração rHVT recombinante (vacinas vetorizadas) vem sendo utilizada em alguns programas vacinais. O objetivo deste estudo foi comparar a replicação das frações CVI e HVT no folículo da pena em três programas imunoprofiláticos distintos (T01 – programa A, T02 – programa B e T03 – programa C). A quantificação das duas estirpes vacinais foi realizada por PCR em tempo real nas amostras colhidas nas idades de 14, 21 e 28 dias. Aos 14 dias, em média, log[cvi] do programa B foi significativamente maior do que C (p<0.05). Aos 21 e 28 dias, a média do log[cvi] do programa C foi significativamente menor do que A e B (p<0.05). Para log[hvt], aos 28 dias, a média do programa B foi significativamente maior do que A (p<0.05). Para proporção de positivos, aos 14 dias, o programa B teve 2,7 vezes mais risco de ter positivos no CVI do que C (p<0.001). Aos 21 dias, o programa B teve 1,7 vezes mais risco de ter positivos no CVI do que C (p=0.005). Para HVT, aos 28 dias, o programa B teve 3,2 vezes mais risco de ter positivos do que A (p=0,009). Os resultados obtidos evidenciam diferenças significativas entre os tratamentos. De maneira geral a vacina convencional de Marek combinada com o CVI e HVT (programa B) apresentou maior taxa de replicação, velocidade e percentual de cobertura vacinal do que os programas compostos com vacinas vetorizadas com rHVT (programa A e C).


Assuntos
Animais , Doença de Marek , Doenças das Aves Domésticas , Vacinas contra Doença de Marek , Vacinação/veterinária
5.
Rev Esc Enferm USP ; 31(2): 287-303, 1997 Aug.
Artigo em Português | MEDLINE | ID: mdl-9411580

RESUMO

The Glasgow Coma Scale (GCS) and the Jouvet Coma Scale (JCS) have been evolved for assessing the depth and duration of impaired consciousness and coma. The analysis and the utilization of these scales have showed that they are complementary. The GCS is more sensitive when there is a more intense loss of consciousness, whereas the JCS shows its sensitivity better in the states close to normal. This study was aimed to compare the results obtained from the evaluation of the consciousness level by the utilization of the two scales. The comparison was done within a prospective study with 48 patients, all of them over 18 years old, interned in three intensive care units of different hospitals in the city of São Paulo. The evaluations were done daily by the researchers and the scales applied in sequence totaling 5 minutes. Each scale was applied in 106 evaluations, and the results showed a statistically meaningful difference between the GCS and the JCS as to the indication of alteration in the consciousness levels. In 37.74% of the evaluations done with the JCS there was an indication of alteration in the consciousness level, whereas with the GCS the alteration was present in only 23.58% of the evaluations. Another important observation about the utilization of both scales was that people whose scores were between 9 and 10 in the GCS had had an stronger indication of alteration of consciousness level by the same scale, while those with scores between 12 and 15 had a stronger indication of alteration in the consciousness level by JCS. When using GCS there has been the application of the non-testable (NT) in 20% of the evaluations. This did not occur when using the JCS. However it is believed that specific conditions of that particular group might have led to that result as well as specific characteristics of groups of patients might favor the utilization of different scales to evaluate the consciousness level. Therefore the final choice between such scales should consider the conditions and the peculiar characteristics of the clientele to be evaluated and not individual or health department services preferences.


Assuntos
Escala de Coma de Glasgow , Exame Neurológico/métodos , Avaliação em Enfermagem/métodos , Inconsciência/enfermagem , Adolescente , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
6.
Ars Vet. ; 34(3): 105-114, 2018. tab, graf
Artigo em Inglês | VETINDEX | ID: vti-738727

RESUMO

Foodborne Salmonella infections in humans, which results from the consumption of contaminated poultry meat and eggs, are a major public health concern. Vaccination of animals against Salmonella is one strategy to prevent these infections and reduce the risks to public health. Live attenuated Salmonella enterica vaccines can confer protection against salmonellosis by inducing both cell-mediated and mucosal immune responses. This study assessed a live, attenuated Salmonella enterica Typhimurium (ST) vaccine in broiler chickens against a heterologous challenge with Salmonella Heidelberg (SH) by evaluating bacterial quantification, immune cells infiltration, and cytokine gene expression in the cecum. The treatments were: T1, non-vaccinated, non-challenged; T2, non-vaccinated, SH-challenged; T3, ST-vaccinated and SH-challenged. At 28 days of age, the ST-vaccinated group had significantly recovered reduction of SH in the crop (P<0,01) and cecum (P = 0,021) compared to the non-vaccinated SH-challenged group, with no significant changes (P˃0,05) in macrophages, T CD4+, or T CD8+ cells dynamics during the same period. Aerosol vaccination on the first day promoted greater interleukin-12 expression in the liver (P<0,05) and interleukin-10 expression and T CD8+ cells in the ileum 16 hours after housing. After prime-boosted oral immunization on the 13th day, the vaccinated group had greater expression of macrophages and T CD4+ cells in the liver (P<0,05) than the control group. Two doses of a live ST-attenuated vaccine promoted a partial cross-protective effect against SH strain UFPR1 challenge in broilers.(AU)


Infecções por Salmonella transmitidas por alimentos como consumo de carne de frango e ovos contaminados em seres humanos constituem um importante problema de saúde pública. A vacinação de animais contra Salmonella é uma estratégia para prevenir essas infecções e reduzir o risco para a saúde pública. As vacinas vivas atenuadas de Salmonella enterica podem conferir proteção contra a salmonelose, induzindo respostas imunológicas mediadas por células e em mucosas. Este estudo avaliou uma vacina viva e atenuada de Salmonella enterica Typhimurium (ST) em frangos de corte contra um desafio heterólogo com Salmonella Heidelberg (SH), avaliando a quantificação de Salmonella, infiltração de células imunes e a expressão de genes de citocinas no ceco. Os tratamentos foram: T1, não vacinado, não desafiado; T2, não vacinado, desafiado com SH; T3, ST-vacinado, desafiado com SH. Aos 28 dias de idade, o grupo vacinado com ST apresentou significativa redução de SH no papo (P<0,01) e no ceco (P = 0,021) comparado ao grupo T2-não vacinado SH-desafiado, sem alterações significativas na dinâmica celular de macrófagos, T CD4+ ou T CD8+ (P˃0,05) durante o mesmo período. A vacinação por aerossol no primeiro dia promoveu maior expressão de IL-12 no fígado (P<0,05), maior expressão de IL-10 e células T CD8+ no íleo, 16 horas após o alojamento. Após o reforço de imunização oral ao 13º dia, o grupo vacinado apresentou maior expressão de macrófagos e células T CD4+ no fígado (P<0,05) do que o grupo controle. Duas doses de uma vacina viva atenuada de ST promoveram um efeito de proteção cruzada parcial contra o desafio da cepa de Salmonella Heidelberg cepa UFPR1 em frangos de corte.(AU)


Assuntos
Animais , Salmonella typhimurium/imunologia , Vacinas contra Salmonella/administração & dosagem , Galinhas , Salmonelose Animal/imunologia , Interleucinas , Macrófagos , Vacinação/veterinária
7.
Ars vet ; 34(3): 105-114, 2018. tab, graf
Artigo em Inglês | VETINDEX | ID: biblio-1463457

RESUMO

Foodborne Salmonella infections in humans, which results from the consumption of contaminated poultry meat and eggs, are a major public health concern. Vaccination of animals against Salmonella is one strategy to prevent these infections and reduce the risks to public health. Live attenuated Salmonella enterica vaccines can confer protection against salmonellosis by inducing both cell-mediated and mucosal immune responses. This study assessed a live, attenuated Salmonella enterica Typhimurium (ST) vaccine in broiler chickens against a heterologous challenge with Salmonella Heidelberg (SH) by evaluating bacterial quantification, immune cells infiltration, and cytokine gene expression in the cecum. The treatments were: T1, non-vaccinated, non-challenged; T2, non-vaccinated, SH-challenged; T3, ST-vaccinated and SH-challenged. At 28 days of age, the ST-vaccinated group had significantly recovered reduction of SH in the crop (P<0,01) and cecum (P = 0,021) compared to the non-vaccinated SH-challenged group, with no significant changes (P˃0,05) in macrophages, T CD4+, or T CD8+ cells dynamics during the same period. Aerosol vaccination on the first day promoted greater interleukin-12 expression in the liver (P<0,05) and interleukin-10 expression and T CD8+ cells in the ileum 16 hours after housing. After prime-boosted oral immunization on the 13th day, the vaccinated group had greater expression of macrophages and T CD4+ cells in the liver (P<0,05) than the control group. Two doses of a live ST-attenuated vaccine promoted a partial cross-protective effect against SH strain UFPR1 challenge in broilers.


Infecções por Salmonella transmitidas por alimentos como consumo de carne de frango e ovos contaminados em seres humanos constituem um importante problema de saúde pública. A vacinação de animais contra Salmonella é uma estratégia para prevenir essas infecções e reduzir o risco para a saúde pública. As vacinas vivas atenuadas de Salmonella enterica podem conferir proteção contra a salmonelose, induzindo respostas imunológicas mediadas por células e em mucosas. Este estudo avaliou uma vacina viva e atenuada de Salmonella enterica Typhimurium (ST) em frangos de corte contra um desafio heterólogo com Salmonella Heidelberg (SH), avaliando a quantificação de Salmonella, infiltração de células imunes e a expressão de genes de citocinas no ceco. Os tratamentos foram: T1, não vacinado, não desafiado; T2, não vacinado, desafiado com SH; T3, ST-vacinado, desafiado com SH. Aos 28 dias de idade, o grupo vacinado com ST apresentou significativa redução de SH no papo (P<0,01) e no ceco (P = 0,021) comparado ao grupo T2-não vacinado SH-desafiado, sem alterações significativas na dinâmica celular de macrófagos, T CD4+ ou T CD8+ (P˃0,05) durante o mesmo período. A vacinação por aerossol no primeiro dia promoveu maior expressão de IL-12 no fígado (P<0,05), maior expressão de IL-10 e células T CD8+ no íleo, 16 horas após o alojamento. Após o reforço de imunização oral ao 13º dia, o grupo vacinado apresentou maior expressão de macrófagos e células T CD4+ no fígado (P<0,05) do que o grupo controle. Duas doses de uma vacina viva atenuada de ST promoveram um efeito de proteção cruzada parcial contra o desafio da cepa de Salmonella Heidelberg cepa UFPR1 em frangos de corte.


Assuntos
Animais , Galinhas , Salmonella typhimurium/imunologia , Salmonelose Animal/imunologia , Vacinas contra Salmonella/administração & dosagem , Interleucinas , Macrófagos , Vacinação/veterinária
8.
Ars Vet. ; 34(2): 69-76, 2018. tab, ilus
Artigo em Inglês | VETINDEX | ID: vti-735285

RESUMO

The purpose of this study was to investigate the effect of a new infectious bursal disease (IBD) immune complex vaccine on immune system response in both specific pathogen-free (SPF) and commercial birds. Evaluation of response to the vaccination in the two experiments was done by histopathological examination and serology. The results of this study have shown that immune complex vaccine with the V877 strain is quite safe in White Leghorn SPF birds in which there has been no participation of maternal antibodies. In commercial birds was also observed that the immune complex vaccine with the V877 strain acted synergistically with different levels of passive antibodies and the vaccine virus began to replicate as passive immunity decreased to provide the animal active immunological response.(AU)


O objetivo desse estudo foi investigar o efeito de uma nova vacina de imunocomplexo contra a doença de Gumboro sobre o sistema imune de aves SPF e comerciais. A avaliação da resposta à vacinação foi realizada por meio de exame histopatológico e sorologia. Os resultados desse estudo demonstraram que a vacina de imunocomplexo com cepa V877 contra Gumboro é muito segura mesmo em aves SPF da linhagem White Leghorn nas quais não existia a participação de imunidade materna. Em aves comerciais também foi demonstrado que a vacina de imunocomplexo com a cepa V877 atuou sinergicamente com diferentes níveis de anticorpos passivos maternais, iniciando a replicação do vírus vacinal a partir do momento que a imunidade passiva diminui, para promover uma resposta imunológica ativa.(AU)


Assuntos
Animais , Aves/imunologia , Vírus da Doença Infecciosa da Bursa/imunologia , ISCOMs/efeitos adversos , ISCOMs/análise , Sorologia , Vacinas , Medicamentos de Referência
9.
Ars vet ; 34(2): 69-76, 2018. tab, ilus
Artigo em Inglês | VETINDEX | ID: biblio-1463447

RESUMO

The purpose of this study was to investigate the effect of a new infectious bursal disease (IBD) immune complex vaccine on immune system response in both specific pathogen-free (SPF) and commercial birds. Evaluation of response to the vaccination in the two experiments was done by histopathological examination and serology. The results of this study have shown that immune complex vaccine with the V877 strain is quite safe in White Leghorn SPF birds in which there has been no participation of maternal antibodies. In commercial birds was also observed that the immune complex vaccine with the V877 strain acted synergistically with different levels of passive antibodies and the vaccine virus began to replicate as passive immunity decreased to provide the animal active immunological response.


O objetivo desse estudo foi investigar o efeito de uma nova vacina de imunocomplexo contra a doença de Gumboro sobre o sistema imune de aves SPF e comerciais. A avaliação da resposta à vacinação foi realizada por meio de exame histopatológico e sorologia. Os resultados desse estudo demonstraram que a vacina de imunocomplexo com cepa V877 contra Gumboro é muito segura mesmo em aves SPF da linhagem White Leghorn nas quais não existia a participação de imunidade materna. Em aves comerciais também foi demonstrado que a vacina de imunocomplexo com a cepa V877 atuou sinergicamente com diferentes níveis de anticorpos passivos maternais, iniciando a replicação do vírus vacinal a partir do momento que a imunidade passiva diminui, para promover uma resposta imunológica ativa.


Assuntos
Animais , Aves/imunologia , ISCOMs/análise , ISCOMs/efeitos adversos , Vírus da Doença Infecciosa da Bursa/imunologia , Medicamentos de Referência , Sorologia , Vacinas
10.
J Mater Sci Mater Med ; 12(10-12): 879-81, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-15348333

RESUMO

Semi-IPN hydrogels (based on cross-linked polyacrylamide having poly(N-isopropylacrylamide) (PN1PAAm) inside) were synthesized and their properties, such as swelling ratio and compressive elastic moduli, were studied at several temperatures. Equilibrium swelling ratios of semi-IPN markedly decreased due to the presence of less hydrophilic PNIPAAm chains. The semi-IPN presented greater elastic modulus when compared to the cross-linked PAAm hydrogel. The effect was explained as being an additional contribution of the PNIPAAm chains, which collapsed around the PAAm networks, to the elastic modulus. It was pointed out that the PAAm networks support the collapsed chains. According to the results presented in this work, semi-IPN hydrogels present better mechanical properties than the PAAm hydrogel, mainly when the PNIPAAm chains are in a collapsed state.

11.
J Mater Sci Mater Med ; 13(12): 1175-80, 2002 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-15348662

RESUMO

In this work, poly(N-isopropylacrylamide) (PNIPAAm) was incorporated into previously oxidized PS and PET surfaces by grafting using two photo-initiation pathways. The incorporation of PNIPAAm was observed by drop water contact angle measurements, dyeing with Methylene Blue and AFM images analysis of the virgin and modified polymers. It was verified that the grafting process depends on the chemical surface environment. The grafted surfaces are hydrophilic below 32 degrees C and hydrophobic above this temperature. The transition is due to the incorporated PNIPAAm. This characteristic gives to the grafted materials potential to be applied as biomaterials.

12.
Ars vet ; 34(3): 105-114, 2018.
Artigo em Português | VETINDEX | ID: vti-32842

RESUMO

Foodborne Salmonella infections in humans, which results from the consumption of contaminated poultry meat and eggs, are a major public health concern. Vaccination of animals against Salmonella is one strategy to prevent these infections and reduce the risks to public health. Live attenuated Salmonella enterica vaccines can confer protection against salmonellosis by inducing both cell-mediated and mucosal immune responses. This study assessed a live, attenuated Salmonella enterica Typhimurium (ST) vaccine in broiler chickens against a heterologous challenge with Salmonella Heidelberg (SH) by evaluating bacterial quantification, immune cells infiltration, and cytokine gene expression in the cecum. The treatments were: T1, non-vaccinated, non-challenged; T2, non-vaccinated, SH-challenged; T3, ST-vaccinated and SH-challenged. At 28 days of age, the ST-vaccinated group had significantly recovered reduction of SH in the crop (P

13.
Ars vet ; 34(2): 69-76, 2018.
Artigo em Português | VETINDEX | ID: vti-31692

RESUMO

The purpose of this study was to investigate the effect of a new infectious bursal disease (IBD) immune complex vaccine on immune system response in both specific pathogen-free (SPF) and commercial birds. Evaluation of response to the vaccination in the two experiments was done by histopathological examination and serology. The results of this study have shown that immune complex vaccine with the V877 strain is quite safe in White Leghorn SPF birds in which there has been no participation of maternal antibodies. In commercial birds was also observed that the immune complex vaccine with the V877 strain acted synergistically with different levels of passive antibodies and the vaccine virus began to replicate as passive immunity decreased to provide the animal active immunological response.

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