Avaliação histológica e por microscopia eletrônica de varredura da biocerâmica de fosfato de cálcio nano-estruturada micromacro porosa em grânulos em defeito crítico de rádio de coelhos / Histological and nano-structured calcium phosphate bioceramic micro-macro porous granules in critical defect rabbits radius scanning electron microscopy evaluation

Objetivou-se avaliar, histologicamente e por microscopia eletrônica de varredura (MEV), a evolução de defeitos críticos experimentais em rádio de coelhos preenchidos ou não com biocerâmica fosfocálcica nanoestruturada micromacro porosa em grânulos. Utilizaram-se 70 coelhos, Nova Zelândia, adultos jovens, machos, e realizou-se um defeito crítico nos rádios. Os membros constituíram os grupos: GI, biocerâmica lenta, GII, biocerâmica moderada e GIII, controle negativo. Após cada período experimental, os animais foram sacrificados, e os rádios coletados. As avaliações histológicas foram realizadas aos oito, 15, 30, 45, 60, 90 e 120 dias, e as análises de MEV aos 60, 90 e 120 dias. Histologicamente, observou-se processo de reparação óssea mais adiantado nos grupos GI e GII comparando-se ao GIII. Na MEV, constatou-se maior proporção de osso maduro e presença de ósteons secundários nos GI e GII, sendo mais evidente no GII, confirmando os achados histológicos. As cerâmicas promoveram preenchimento completo do defeito, enquanto no grupo controle houve preenchimento no centro do defeito, permanecendo espaços vazios nas laterais. Conclui-se que o emprego das biocerâmicas de absorção lenta e moderada favorece a regeneração óssea completa em defeitos críticos sendo indicadas como substituto ósseo. A maturação óssea ocorre mais precocemente quando se emprega a cerâmica de absorção moderada.(AU)

The objective was to evaluate, through histologic exam and by scanning electron microscopy (SEM), the evolution of experimental critical defects in radio or not filled with nano-structured calcium phosphate micro-macro porous bioceramic granules rabbits. We used 70 rabbits, New Zealand, young adults, males, there was a critical defect in radio. The members were the groups: GI, slow bioceramic, GII, GIII and bioceramic moderate, negative control. After each experimental period, the animals were sacrificed and the radios harvested. Histological evaluations were performed at eight, 15, 30, 45, 60, 90 and 120 days and SEM analyzes at 60, 90 and 120 days. Histologically there was bone healing process earlier in GI and GII compared to GIII. In SEM we observed a higher proportion of mature bone and presence of secondary osteons in GI and GII, being more evident in the GII, confirming the histological findings. Ceramic promoted complete filling of the defect, while the control group was filling in the center of the defect, with empty spaces remaining on the sides. In conclusion, the use of bioceramics, slow and moderate absorption favor complete bone regeneration in critical defects being indicated as a bone substitute. The maturation occurs earlier when employing the ceramic moderate absorption.(AU)

Avaliação histológica e por microscopia eletrônica de varredura da biocerâmica de fosfato de cálcio nano-estruturada micromacro porosa em grânulos em defeito crítico de rádio de coelhos / Histological and nano-structured calcium phosphate bioceramic micro-macro porous granules in critical defect rabbits radius scanning electron microscopy evaluation

Objetivou-se avaliar, histologicamente e por microscopia eletrônica de varredura (MEV), a evolução de defeitos críticos experimentais em rádio de coelhos preenchidos ou não com biocerâmica fosfocálcica nanoestruturada micromacro porosa em grânulos. Utilizaram-se 70 coelhos, Nova Zelândia, adultos jovens, machos, e realizou-se um defeito crítico nos rádios. Os membros constituíram os grupos: GI, biocerâmica lenta, GII, biocerâmica moderada e GIII, controle negativo. Após cada período experimental, os animais foram sacrificados, e os rádios coletados. As avaliações histológicas foram realizadas aos oito, 15, 30, 45, 60, 90 e 120 dias, e as análises de MEV aos 60, 90 e 120 dias. Histologicamente, observou-se processo de reparação óssea mais adiantado nos grupos GI e GII comparando-se ao GIII. Na MEV, constatou-se maior proporção de osso maduro e presença de ósteons secundários nos GI e GII, sendo mais evidente no GII, confirmando os achados histológicos. As cerâmicas promoveram preenchimento completo do defeito, enquanto no grupo controle houve preenchimento no centro do defeito, permanecendo espaços vazios nas laterais. Conclui-se que o emprego das biocerâmicas de absorção lenta e moderada favorece a regeneração óssea completa em defeitos críticos sendo indicadas como substituto ósseo. A maturação óssea ocorre mais precocemente quando se emprega a cerâmica de absorção moderada.(AU)

The objective was to evaluate, through histologic exam and by scanning electron microscopy (SEM), the evolution of experimental critical defects in radio or not filled with nano-structured calcium phosphate micro-macro porous bioceramic granules rabbits. We used 70 rabbits, New Zealand, young adults, males, there was a critical defect in radio. The members were the groups: GI, slow bioceramic, GII, GIII and bioceramic moderate, negative control. After each experimental period, the animals were sacrificed and the radios harvested. Histological evaluations were performed at eight, 15, 30, 45, 60, 90 and 120 days and SEM analyzes at 60, 90 and 120 days. Histologically there was bone healing process earlier in GI and GII compared to GIII. In SEM we observed a higher proportion of mature bone and presence of secondary osteons in GI and GII, being more evident in the GII, confirming the histological findings. Ceramic promoted complete filling of the defect, while the control group was filling in the center of the defect, with empty spaces remaining on the sides. In conclusion, the use of bioceramics, slow and moderate absorption favor complete bone regeneration in critical defects being indicated as a bone substitute. The maturation occurs earlier when employing the ceramic moderate absorption.(AU)

Avaliação histológica e por microscopia eletrônica de varredura da biocerâmica de fosfato de cálcio nano-estruturada micromacro porosa em grânulos em defeito crítico de rádio de coelhos

ABSTRACT The objective was to evaluate, through histologic exam and by scanning electron microscopy (SEM), the evolution of experimental critical defects in radio or not filled with nano-structured calcium phosphate micro-macro porous bioceramic granules rabbits. We used 70 rabbits, New Zealand, young adults, males, there was a critical defect in radio. The members were the groups: GI, slow bioceramic, GII, GIII and bioceramic moderate, negative control. After each experimental period, the animals were sacrificed and the radios harvested. Histological evaluations were performed at eight, 15, 30, 45, 60, 90 and 120 days and SEM analyzes at 60, 90 and 120 days. Histologically there was bone healing process earlier in GI and GII compared to GIII. In SEM we observed a higher proportion of mature bone and presence of secondary osteons in GI and GII, being more evident in the GII, confirming the histological findings. Ceramic promoted complete filling of the defect, while the control group was filling in the center of the defect, with empty spaces remaining on the sides. In conclusion, the use of bioceramics, slow and moderate absorption favor complete bone regeneration in critical defects being indicated as a bone substitute. The maturation occurs earlier when employing the ceramic moderate absorption.

RESUMO Objetivou-se avaliar, histologicamente e por microscopia eletrônica de varredura (MEV), a evolução de defeitos críticos experimentais em rádio de coelhos preenchidos ou não com biocerâmica fosfocálcica nanoestruturada micromacro porosa em grânulos. Utilizaram-se 70 coelhos, Nova Zelândia, adultos jovens, machos, e realizou-se um defeito crítico nos rádios. Os membros constituíram os grupos: GI, biocerâmica lenta, GII, biocerâmica moderada e GIII, controle negativo. Após cada período experimental, os animais foram sacrificados, e os rádios coletados. As avaliações histológicas foram realizadas aos oito, 15, 30, 45, 60, 90 e 120 dias, e as análises de MEV aos 60, 90 e 120 dias. Histologicamente, observou-se processo de reparação óssea mais adiantado nos grupos GI e GII comparando-se ao GIII. Na MEV, constatou-se maior proporção de osso maduro e presença de ósteons secundários nos GI e GII, sendo mais evidente no GII, confirmando os achados histológicos. As cerâmicas promoveram preenchimento completo do defeito, enquanto no grupo controle houve preenchimento no centro do defeito, permanecendo espaços vazios nas laterais. Conclui-se que o emprego das biocerâmicas de absorção lenta e moderada favorece a regeneração óssea completa em defeitos críticos sendo indicadas como substituto ósseo. A maturação óssea ocorre mais precocemente quando se emprega a cerâmica de absorção moderada.

Ocorrência de anticorpos anti-Neospora spp. em jumentos (Equus asinus) no estado de Sucre - Colômbia / Occurrence of anti-Neospora spp. Antibodies in donkeys (Equus asinus) in the state of Sucre - Colombia

A neosporose tem grande importância em bovinos, e sua patogênese neste hospedeiro, em termos gerais, está esclarecida, porém, em equídeos é pobremente conhecida. Na Colômbia ainda não foram reportados anticorpos Anti-Neospora spp. em equídeos, sendo assim objetivou-se no presente estudo avaliar a ocorrência do parasito em jumentos (Equus asinus) de fazendas que apresentavam risco da doença nestes animais. Foram utilizados 56 animais no estado de Sucre (Colômbia), escolhidos aleatoriamente dentro das fazendas selecionadas. Utilizou-se um peptídeo recombinante originado de Neospora caninum (NcGRA1) para o diagnóstico por Dot-ELISA, e o soro foi diluído em 1:200. Este estudo reporta, pela primeira vez no estado de Sucre e na Colômbia, a presença de anticorpos anti-Neospora spp. na espécie Equus asinus, com uma ocorrência de 19,7% (11/56) dos animais amostrados...

The neosporosis has great importance in cattle, and its pathogenesis in this host has been generally clarified, however, in horses, neosporosis is poorly known, and in Colombia anti-Neospora spp antibodies have not been reported. Therefore, the main objective in the present study was to evaluate the occurrence of this parasite in donkeys (Equus asinus) from farms that presented a risk of disease in these animals, as well as no health plan for them. Were used 56 animals randomly chosen inside selected farms in the state of Sucre (Colombia). A recombinant peptide originated from Neospora caninum (NcGRA1) was used for the diagnosis with Dot-ELISA and serum was diluted 1:200. This study is the first to report the presence of anti-Neospora spp. in donkeys (Equus asinus) in the state of Sucre, and in Colombia. The occurrence was in 19.7% of the animals sampled (11/56)...

Ocorrência de anticorpos anti-Neospora spp. em jumentos (Equus asinus) no estado de Sucre - Colômbia / Occurrence of anti-Neospora spp. Antibodies in donkeys (Equus asinus) in the state of Sucre - Colombia

A neosporose tem grande importância em bovinos, e sua patogênese neste hospedeiro, em termos gerais, está esclarecida, porém, em equídeos é pobremente conhecida. Na Colômbia ainda não foram reportados anticorpos Anti-Neospora spp. em equídeos, sendo assim objetivou-se no presente estudo avaliar a ocorrência do parasito em jumentos (Equus asinus) de fazendas que apresentavam risco da doença nestes animais. Foram utilizados 56 animais no estado de Sucre (Colômbia), escolhidos aleatoriamente dentro das fazendas selecionadas. Utilizou-se um peptídeo recombinante originado de Neospora caninum (NcGRA1) para o diagnóstico por Dot-ELISA, e o soro foi diluído em 1:200. Este estudo reporta, pela primeira vez no estado de Sucre e na Colômbia, a presença de anticorpos anti-Neospora spp. na espécie Equus asinus, com uma ocorrência de 19,7% (11/56) dos animais amostrados.(AU)

The neosporosis has great importance in cattle, and its pathogenesis in this host has been generally clarified, however, in horses, neosporosis is poorly known, and in Colombia anti-Neospora spp antibodies have not been reported. Therefore, the main objective in the present study was to evaluate the occurrence of this parasite in donkeys (Equus asinus) from farms that presented a risk of disease in these animals, as well as no health plan for them. Were used 56 animals randomly chosen inside selected farms in the state of Sucre (Colombia). A recombinant peptide originated from Neospora caninum (NcGRA1) was used for the diagnosis with Dot-ELISA and serum was diluted 1:200. This study is the first to report the presence of anti-Neospora spp. in donkeys (Equus asinus) in the state of Sucre, and in Colombia. The occurrence was in 19.7% of the animals sampled (11/56).(AU)

Porcine circovirus-2 viral load versus lesions in pigs: perspectives for post-weaning multisystemic wasting syndrome.

Porcine circovirus-2 (PCV-2) is the main agent related to post-weaning multisystemic wasting syndrome (PMWS) and it is also associated with other syndromes affecting pigs. Not all pigs infected with PCV-2 will develop PMWS and the incidence of PMWS is higher when coinfecting viral and bacterial pathogens are present. In this study, PCV-2 viral loads were evaluated in the tissues of animals with and without PMWS in order to investigate the relationship between viral load and microscopical lesions. Lymph nodes had the highest average viral load, but there was no significant difference between lesion severity and the viral load in these structures. There was no significant difference between the average viral load in inguinal lymph nodes of animals with and without PMWS. However, samples from pigs with PMWS had more severe lesions compared with samples from non-PMWS animals. These findings suggest that other infectious and non-infectious cofactors may be important in the pathogenesis of PMWS.

Immune response of bovines stimulated by synthetic vaccine SBm7462 against Rhipicephalus (Boophilus) microplus.

Ten-month-old calves Bos taurus taurus were immunized with three doses of SBm7462 with saponin as an adjuvant at 30-day intervals and were evaluated for IgG isotypes, phenotype circulating lymphocytes and changes in the lymph nodes (LN). SBm7462 stimulated the production of predominantly IgG1-isotype IgG antibodies. The lymph nodes exhibited activation at the seventh day after the first immunization, with areas of paracortical and interfollicular hyperplasia and the early formation of germinal centers (GC). Fifteen days after the first immunization, the GC exhibited compartmentalization of cellular populations, a light zone (LZ), a dark zone (DZ) and a mantle. At the same time, hyperplasia of the medullary cords was observed with cells associating with DC cells. Seven days after the first immunization, apoptosis in the DZ and in the paracortical region became evident. By day 15, there was an increase in the medullary cords, which became more numerous at days 35 and 42. PAP-positive cells were found in the paracortical region, medullary cords and GC 7 days after the first immunization. At day 35, there were further strongly PAP-positive cells in the medullary cords. By comparison, none of these changes were observed in the lymph nodes of control groups at any of the days analyzed. The number of CD21(+) lymphocytes increased in the immunized groups after the first inoculation, with a maximum number observed at 15 and 10 days after the first and third immunizations, respectively. Compared to pre-immunization counts, the percentage of WC1(+) gammadelta T-lymphocytes displayed more variation, increasing 5 days after the second immunization but decreasing over the following days. According to the results, the synthetic anti Rhipicephalus microplus vaccine elicits a complete immune response being T-dependant.

Resposta tecidual ao compósito 50 por cento hidroxiapatita: 50 por cento poli-hidroxibutirato para substituição óssea em coelhos / Tissue response to the composite 50 percent hydroxyapatite: 50 percent polyhydroxybutyrate for bone substitution in rabbits

Avaliaram-se a biocompatibilidade, a osseointegração, a osseocondução e a biodegradação de compósitos de 50 por cento hidroxiapatita (HAP-91®) e 50 por cento poli-hidroxibutirato. O compósito foi implantado em defeitos ósseos em 12 coelhos (grupo experimental), sendo comparado a defeitos não preenchidos (grupo-controle, de igual número). Os parâmetros clínicos dor, claudicação, infecção, deiscência e edema foram avaliados nos primeiros oito dias após a cirurgia e aos 45 e 90 dias. Radiografias foram realizadas aos oito, 45 e 90 dias após a cirurgia em quatro animais por grupo que, em seguida, foram submetidos à eutanásia para coleta de amostras destinadas a análises histológica e histomorfométrica. Não ocorreram diferenças entre os grupos para todos os parâmetros clínicos. Radiografias demonstraram um compósito com radiopacidade semelhante à do osso vizinho e contato direto entre osso e compósito aos 45 e 90 dias. Diferença significativa foi observada entre a porcentagem dos tecidos ósseo e conjuntivo dentro do defeito nos dias oito, 45 e 90, assim como na interface aos 45 e 90 dias. Foram observadas projeções dos tecidos ósseo e conjuntivo no interior do compósito e sinais de biodegradação na ausência de infiltrado inflamatório. Pode-se concluir que o compósito é biocompatível, osseocondutor, biodegradável e se integra ao tecido ósseo.

The biocompatibility, osseointegration, osseoconductivity, and biodegradation of a 50-50 percent hydroxyapatite (HAP-91®)-polyhydroxybutyrate were evaluated. The composite was implanted in bone defects of 12 rabbits (experimental group), being compared to unfilled defects (control group, 12 animals). The clinical parameters of pain, lameness, infection, dehiscence, and edema were evaluated during the first eight days and on the 45th and 90th days after surgery. Radiographs were taken in four animals per group at 8, 45, and 90 days after surgery, when animals were euthanized to collect samples for histology and histomorphometry. Significant differences between groups for all clinical parameters were not observed. Radiographs showed a similar radiopacity of the composite and bone and their direct contact. More bone than connective tissue was found within the defect at 8, 45, and 90 days and at the interface on the 45th and 90th days. Projections of bone and connective tissue were seen inside the composite. Biodegradation signs became evident, with absence of inflammatory infiltrate. Data support that such composite is biocompatible, osseoconductive, biodegradable, and integrate to bone.

Resposta tecidual ao compósito 50 por cento hidroxiapatita: 50 por cento poli-hidroxibutirato para substituição óssea em coelhos / Tissue response to the composite 50 percent hydroxyapatite: 50 percent polyhydroxybutyrate for bone substitution in rabbits

Avaliaram-se a biocompatibilidade, a osseointegração, a osseocondução e a biodegradação de compósitos de 50 por cento hidroxiapatita (HAP-91®) e 50 por cento poli-hidroxibutirato. O compósito foi implantado em defeitos ósseos em 12 coelhos (grupo experimental), sendo comparado a defeitos não preenchidos (grupo-controle, de igual número). Os parâmetros clínicos dor, claudicação, infecção, deiscência e edema foram avaliados nos primeiros oito dias após a cirurgia e aos 45 e 90 dias. Radiografias foram realizadas aos oito, 45 e 90 dias após a cirurgia em quatro animais por grupo que, em seguida, foram submetidos à eutanásia para coleta de amostras destinadas a análises histológica e histomorfométrica. Não ocorreram diferenças entre os grupos para todos os parâmetros clínicos. Radiografias demonstraram um compósito com radiopacidade semelhante à do osso vizinho e contato direto entre osso e compósito aos 45 e 90 dias. Diferença significativa foi observada entre a porcentagem dos tecidos ósseo e conjuntivo dentro do defeito nos dias oito, 45 e 90, assim como na interface aos 45 e 90 dias. Foram observadas projeções dos tecidos ósseo e conjuntivo no interior do compósito e sinais de biodegradação na ausência de infiltrado inflamatório. Pode-se concluir que o compósito é biocompatível, osseocondutor, biodegradável e se integra ao tecido ósseo.(AU)

The biocompatibility, osseointegration, osseoconductivity, and biodegradation of a 50-50 percent hydroxyapatite (HAP-91®)-polyhydroxybutyrate were evaluated. The composite was implanted in bone defects of 12 rabbits (experimental group), being compared to unfilled defects (control group, 12 animals). The clinical parameters of pain, lameness, infection, dehiscence, and edema were evaluated during the first eight days and on the 45th and 90th days after surgery. Radiographs were taken in four animals per group at 8, 45, and 90 days after surgery, when animals were euthanized to collect samples for histology and histomorphometry. Significant differences between groups for all clinical parameters were not observed. Radiographs showed a similar radiopacity of the composite and bone and their direct contact. More bone than connective tissue was found within the defect at 8, 45, and 90 days and at the interface on the 45th and 90th days. Projections of bone and connective tissue were seen inside the composite. Biodegradation signs became evident, with absence of inflammatory infiltrate. Data support that such composite is biocompatible, osseoconductive, biodegradable, and integrate to bone.(AU)

Synthetic vaccine (SBm7462) against the cattle tick Rhipicephalus (Boophilus) microplus: preservation of immunogenic determinants in different strains from South America.

The synthetic vaccine SBm7462 is based on three immunogenic epitopes (4822, 4823 and 4824) contained within protein Bm86 derived from the Australian Yeerongpilly strain of the tick Rhipicephalus (Boophilus) microplus. Twenty strains of the tick originating from Brazil, Argentina, Colombia and Uruguay were analysed in order to identify differences compared with sequences present in components of vaccine SBm7462. For each parasite population, three cDNA fragments containing the nucleotides coding for the epitopes 4822, 4824 and 4823 were sequenced, and the amino acid sequences were deduced and compared with those of the homologous bm86 gene. The results indicate that the epitope sequences of vaccine SBm7462 are conserved in the South American populations of the tick. The conservation of such sequences is very important for the immunological response of different populations of R. (B.) microplus.

Use of biodegradable PLGA microspheres as a slow release delivery system for the Boophilus microplus synthetic vaccine SBm7462.

The synthetic anti-Boophilus microplus vaccine SBm7462 derived from the tick intestinal protein, Bm86, induced a protective immune response when emulsified in saponin and used in cattle. Using a mice model, and with the objective of improving the vaccine by continual peptide release, it was encapsulated in PLGA 50:50 microspheres and inoculated in BALB/c mice to assess the immunological response by detection of anti-peptide IgGs. Comparative studies were made with the peptide emulsified in saponin and with another synthetic vaccine, and the microsphere/peptide was characterized for efficiency of encapsulation, in vitro release profile, morphology, size, peptide integrity after encapsulation and stability in different pHs. The findings showed that saponin enhances a better immune response from SBm7462 and that the PLGA 50:50 microspheres are suitable for use with this peptide.

Exoantigens of an attenuated strain of Babesia bovis used as a vaccine against bovine babesiosis.

Bovine babesiosis caused by Babesia bovis remains a significant constraint to beef and milk cattle production throughout the world. Exoantigens released by the parasites in culture supernatants are a potential source of antigen to induce protective immunity. An attenuated strain of B. bovis from Brazil, catalogued as BbUFV1, was maintained in vitro by the MASP method, and exoantigen-containing supernatant fluids were collected daily to form a pool representing a 72-h culture cycle for preparation of the vaccine. Exoantigen concentration was estimated using a two-site EIA. Three groups of susceptible non-splenectomised male Bos taurus cattle, 14 months old, were used. Group A (vaccinated) received two subcutaneous immunizations with a 21-day interval of B. bovis supernatant, content 6500 EIA units of exoantigens plus 1.5 mg saponin, and Group B (adjuvant control) received two injections of adjuvant alone. Four weeks after the second immunization, Groups A, B and C (control) were challenged intravenously with 10(8) virulent parasites of a heterologous B. bovis strain. The results showed that exoantigens present in in vitro cultures can induce a high degree of protection against virulent heterologous challenge exposure. In Group A only one animal showed discrete parasitaemia; all developed a fever and slight decreases in PCV, with a rapid return to normal values. One animal of Group B died; the survivors showed fever, anaemia and parasitaemia. All animals of Group C died between 7 and 13 days after challenge. Vaccination elicited both humoral and cell-mediated immune responses. In Group A, after the challenge, the maximum antibody titer was 12,800. When vaccinated, cattle were tested at the moment of challenge for B. bovis-specific cell-mediated immunity by the monocytemigration inhibition test. A mean inhibition index of 60 +/- 0.33 was observed. Preliminary Western blot analysis of the immunogen revealed at least four proteins of molecular weight ranging between 30 and 160 kDa.

Description of lesions in cattle in a natural outbreak of Babesia bovis infection in Brazil.

This paper describes the pathologic features of a natural infection by Babesia bovis (B. argentina) in Brazil. Microscopic examination of cerebrum, midbrain, cerebellum, liver, kidney, heart and spleen of five fatal cases revealed variable degrees of congestion, particularly in the brain, liver and kidney. The packing of erythrocytes, the majority of which were parasitized, was most marked in the capillaries of brain, kidney and less in liver. Lymphocytic glomerulonephritis was observed. Variable degrees of fatty degeneration were noted in the liver, distention of hepatic canaliculi and biliary retention was marked. A strong activation of the mononuclear phagocytic system was evident in all the subjects studied.