RESUMO

Neospora caninum is a globally distributed abortifacient protozoan of cattle. Experimental infections with N. caninum in cattle have provided valuable information on host-parasite interaction and immunopathogenesis. Experimental infection of pregnant cows has been reported in about 20 articles, with most studies using cultured parasite tachyzoites as the inoculum. Only three experimental studies have been conducted in pregnant cows using the parasite's oocysts which are shed by dogs, in large part because transmission experiments using oocysts take more time and are more complex and expensive than experiments using tachyzoites. In this minireview, we discuss differences between N. caninum tachyzoites and oocysts as inocula for experimental infection of pregnant cows, as well as the route animals are inoculated.

RESUMO

HoBi-like pestivirus (HoBiPeV) has been reported in several biological samples from cattle worldwide, but there are no descriptions of this virus associated with neurological symptoms. This report described the first occurrence of neurological disease associated with HoBiPeV in a newborn dairy calf. A mixed-breed Holstein calf had severe neurological symptoms at birth and died at 21 days old. The tissue fragments (central nervous system (CNS), myocardium, liver, kidney, lung, intestine, and spleen) were submitted to reverse transcription (RT)-PCR assay for the partial 5'-untranslated region (5'UTR) and N-terminal autoprotease (Npro) gene of the pestivirus genome, and the CNS tissue fragments were submitted to histopathological and immunohistochemical evaluation. The RT-PCR assay indicated that the kidney, CNS, and intestinal tissue fragments were positive for the pestivirus 5'UTR, and the CNS and intestinal tissue fragments were positive for the pestivirus Npro gene. Amplicons with high DNA quantification in the 5'UTR (CNS-cerebral cortex) and Npro (CNS-cerebral cortex and intestine) RT-PCR assays were sequenced. The nucleotide (nt) sequence and phylogenetic analysis of the 5'UTR strain exhibited 93.6 to 99.4%, 85%, 89.4 to 89.9%, 85.1%, and 90.5 to 91.5% nt identity with HoBiPeV strains from clades a, b, c, d, and e, respectively. The Npro amplicons showed 99.7% nt identity to each other and 90.4 to 96.5%, 85.1 to 85.3%, 79.2 to 79.7%, and 85.8 to 86.5% nt identity with HoBiPeV strains from clades a, c, d, and e, respectively. A histopathology revealed neuronal necrosis at the cerebrum, cerebellum, and brain stem. An immunohistochemical assay designed to identify antigens of bovine viral diarrhea virus revealed positive intracytoplasmic immunoreactivity within neurons at the cerebral cortex, cerebrum, cerebellum, and spinal cord. Thus, this report provides information about the first identification of HoBiPeV in tissues of the CNS in a newborn dairy calf with neurological symptoms.

RESUMO

Probiotics have been shown to reduce the intensity of Toxocara canis infection in mice. However, larval transmission of this nematode also occurs via transplacental and transmammary routes. Thus, the aim of this study was to evaluate the effect of the Saccharomyces boulardii probiotic on the vertical transmission of T. canis in Swiss mice. The mice received 107S. boulardii colony-forming units per gram of food. The supplementation began 15 days before mating and was maintained throughout pregnancy and lactation. The animals were inoculated with 300 T. canis embryonated eggs on the 14th day of pregnancy. The presence of larvae was examined in the organs of the females and their offspring. The examined organs included the following: brain, liver, lungs, heart, kidneys, spleen, eye, skeletal muscle (carcass) and mammary glands of lactating females. There was a 42% (P = 0.041) reduction in the number of larvae transmitted to offspring in the group that received probiotic-supplemented food (GI). Additionally, there was a 50% reduction (P = 0.023) in the number of larvae found in the brains of lactating offspring in the GI group. These results reveal the potential of S. boulardii probiotic use as an auxiliary method of controlling visceral toxocariasis.

Assuntos

RESUMO

ANTECEDENTES: La pandemia global de COVID-19 llega al continente americano en marzo del año 2020 y en menos de dos meses reúne a más de la mitad de los casos a nivel global. OBJETIVO: Caso clínico de una mujer embarazada con una presentación crítica de COVID-19 y embarazo a las 25 semanas de gestación, en el contexto del peak de la pandemia en Chile en el otoño del año 2020. CASO CLÍNICO: El 20 de junio de 2020, una mujer de 34 años, con 25 semanas de embarazo, es trasladada desde Hospital de San Bernardo a Clínica Las Condes en Santiago, Chile, con un cuadro de 10 días de evolución de COVID-19, que evoluciona a una situación crítica con insuficiencia respiratoria severa. Ingresa a unidad de cuidados intensivos para ventilación mecánica. Las imágenes de radiología simple y de tomografía axial computarizada de tórax demuestran una neumopatía bilateral con imágenes características opacidades en vidrio esmerilado, asociado a engrosamiento intersticial, imágenes descritas previamente como características para COVID-19. La paciente permanece en unidad de cuidados intensivos en ventilación mecánica por siete días, con evolución favorable posterior, mejoría del cuadro séptico y alta después de 22 días de hospitalización. El parto ocurre en forma espontánea a las 38 semanas, la madre y el recién nacido evolucionan en buen estado general. El examen histopatológico placentario demuestra compromiso inflamatorio vellositario y los exámenes de anticuerpos en sangre del recién nacido demuestran la presencia de anticuerpos del tipo IgG e IgM. Se trata de uno de los pocos casos demostrados reportados de transmisión transplacentaria vía sanguínea de SARS-CoV-2 de la madre al recién nacido.

BACKGROUND: The global COVID-19 pandemic reaches the American continent in March 2020 and in less than two months it brings together more than half of the cases globally.OBJECTIVE: The clinical case of a 25-week pregnant woman with a critical presentation of COVID-19 and pregnancy at 25 weeks of gestation, is presented in the context of the peak of the pandemic in Chile in the fall of 2020. CLINICAL CASE: On June 20, 2020, a 34-year-old woman, 25 weeks pregnant, is transferred from Hospital de San Bernardo to Clinica Las Condes in Santiago, Chile, with a ten-day evolution of a COVID-19 that evolves to critical with severe respiratory failure. She is admitted to the intensive care unit for mechanical ventilation. Chest computerized axial tomography images demonstrate bilateral pneumopathy with characteristic images of ground-glass opacities, associated with interstitial thickening, images previously described as characteristics for COVID-19. The patient remains in the intensive care unit on mechanical ventilation for seven days, with subsequent favorable evolution, improvement of the septic condition, and discharge after 22 days of hospitalization. Delivery occurs at 38 weeks, the mother and the newborn evolve in good general condition. The placental histopathological examination demonstrates villous inflammatory involvement, and the newborn's blood tests show the presence of IgG and IgM antibodies. It is one of the few reported cases of transplacental transmission of SARS-CoV-2 from the mother to the newborn.

Assuntos

RESUMO

INTRODUCTION: The objective of this study was to evaluate the presence of anti-Sarcocystis spp. specific IgG antibodies in serum samples from precolostral lambs to determine the occurrence of transplacental transmission of Sarcocystis spp. in sheep. METHODS: Blood samples were collected from 80 ewes and their respective lambs, immediately after lambing and before colostrum ingestion, respectively. The presence of anti-Sarcocystis spp. IgG was evaluated in serum samples using the indirect fluorescent antibody test (IFAT). Positive samples of the lambs were submitted to titration and IFAT to detect anti-T. gondii and anti-N. caninum specific IgG. RESULTS: Anti-Sarcocystis spp. IgG was detected in 62.5% of the ewes (50/80) and in 4% of the lambs of the seropositive ewes (2/50). None of the lambs from seronegative ewes were positive. The final titers of the positive lambs were 80. No cross reaction was detected among the positive samples to anti-Sarcocystis spp., anti-N. caninum, and anti-T. gondii IgG. The detection of anti-Sarcocystis spp. antibodies in serum samples of lambs deprived of colostrum suggests transplacental transmission of infection. Thus, the vertical transmission may be an alternative route of infection of Sarcocystis spp. also in sheep. Further studies are warranted to confirm transplacental transmission in sheep and to explain the importance of this infection pathway.

Assuntos

RESUMO

Neospora caninum is an obligate intracellular protozoan, recognized as an important cause of abortion in infection cattle worldwide, and is responsible for major economic losses in beef and dairy herds. There are scarce data on the presence of antibodies in fetal serum samples from beef cattle. The pathogen is straggling mainly by vertical transmission in ruminants. This study aimed to determine the frequency of anti-N. caninum antibodies in fetal bovine serum. Overall, 751 fetal serum samples from slaughterhouses in Uruguaiana and Santo Ângelo (Rio Grande do Sul state) were used. Serologic diagnosis was made using indirect immunofluorescence assay (IFA). Slides were prepared by culturing infected Vero cells using tachyzoites of the N. caninum NC-1 strain and a serum dilution of 1:25. Of the 751 samples analyzed, 11.7% (88/751) were positive in the IFA assay. The results indicate an occurrence of neosporosis in the studied region, as well as the possibility of transplacental transmission of the protozoon, characterizing an important mechanism of propagation for the disease.(AU)

O Neospora caninum é um protozoário intracelular obrigatório, reconhecido como uma causa importante de aborto no mundo todo, e é responsável pelas maiores perdas da economia de carne e leite. Há poucos dados da presença de anticorpos em amostras de soro fetal de bovinos de corte. Os patógenos são transmitidos principalmente por transmissão vertical em ruminantes. Este estudo pode ser usado para determinar a frequência de anti-N. caninum em soro fetal bovino. Ao todo, foram utilizadas 751 amostras de soro fetal bovino de matadouros de Uruguaiana e Santo Ângelo (RS). Os diagnósticos sorológicos foram realizados utilizando ensaios de imunufluorescência indireta (IFA). As lâminas foram preparadas por cultura de células Vero infectadas utilizando taquizoítos da estirpe N. caninum NC-1 e uma diluição de soro de 1:25. Das 751 amostras analisadas, 11,7% (88/751) foram positivas para o IFA. Os resultados indicam uma ocorrência de neosporose na região estudada, bem como a possibilidade de transmissão transplacentária do protozoário, caracterizando um importante mecanismo de propagação da doença.(AU)

Assuntos

RESUMO

Neospora caninum infection of cattle can be vertically transmitted, resulting in abortion or birth of infected calves. Vertical transmission occurs both in acutely or chronically infected cattle. There is little information on the immune response needed to prevent endogenous transplacental transmission, particularly from chronically infected cattle to their offspring in a natural environment. In this study, N. caninum seropositive pregnant cattle from three different farms with high avidity antibodies and low IgM titers were selected and their newborn colostrum-deprived calves were tested for anti-N. caninum antibodies. Based on these results, dams were grouped according to their congenital transmission status. The analysis of the immune profile of the chronically-infected pregnant cattle revealed that higher ratio between IgG1 and IgG2 anti-N. caninum serum titers and higher levels of systemic IFN-γ were associated with diminished vertical transmission rates, compared to dams with the opposite profile. Our results evidenced an association between the immune profile and vertical transmission in non-aborting chronically infected dams, and confirm that vertical transmission, even when not leading to abortion, is related to a defined immune profile. This is important information to accomplish successful vaccine development efforts.

Assuntos

RESUMO

Much progress with respect to congenital Zika virus (ZIKV) pathogenesis has been achieved after the 2015 outbreak in Brazil. It is now accepted that ZIKV is vertically transmitted, infects cells of the developing central nervous system and the placenta, yet it is unclear to what extent placental affection contributes to the development of congenital ZIKV. The association between fulminant villitis and severe fetal involvement emerges as a possibility. ZIKV is unique among the Flaviviruses in its ability to be sexually transmitted, possibly responsible for its teratogenicity. Furthermore, there is controversy over the participation of antibody dependent enhancement (ADE) in patients with non-neutralizing anti-Flavivirus antibodies, a phenomenon previously recognized in serious DENV infections. Our aim was to analyze information regarding the contribution of the placental barrier as an actual player in neonatal ZIKV. Therefore, we underwent a systematic review with keywords "Zika virus" and "ZIKV". Articles were screened for relevance concerning the topics of microcephaly, transplacental transmission, sexual transmission, and ADE. We identified variables that affect the severity of congenital Zika syndrome: age of gestation at maternal infection, the extent of placental disruption (villitis), sexual transmission, initial viral replication at the uterine wall, anti-DENV antibodies, and the possibility of antibody-mediated transcytosis of ZIKV through the placenta. These questions may not seem relevant when Zika becomes endemic, and we are no longer witness to the extreme clinical sequelae seen when the virus moves through an immunologically naïve population; however, characterizing the pathogenesis of congenital Zika syndrome will continue to further our understanding.

Assuntos

RESUMO

Toxoplasma gondii and Neospora caninum are causative agents of abortion in sheep and goats. Thus, the present study aimed to describe the transplacental transmission of these protozoans in small ruminants of northeastern Brazil. Seventeen fetuses (6 goats and 11 sheep) from farms with history of abortion were necropsied and samples were collected from different tissues (brain, liver, lung, kidney and heart). The samples were analyzed by PCR, histopathology (HP) and immunohistochemistry (IHC) to evaluate whether T. gondii and/or N. caninum infection were the cause of abortion. None of the samples was positive for T. gondii according to PCR and IHC results. Some brain, liver, lung, kidney and heart samples of goat fetuses were positive for N. caninum by PCR. In the histopathology, mild mononuclear infiltration and necrosis with calcification were observed in the liver and brain of one goat fetus, respectively, that also was positive for N. caninum by PCR and IHC. The results confirmed vertical transmission of N. caninum in naturally infected goats of northeastern, Brazil.(AU)

Toxoplasma gondii e Neospora caninum são reconhecidos como protozoário causadores de aborto em ovinos e caprinos. Desta forma, objetivou-se descrever a transmissão transplacentária desses agentes em pequenos ruminantes na região Nordeste do Brasil. Foram examinados seis fetos caprinos e onze fetos ovinos, totalizando 78 amostras de diferentes tecidos (cérebro, fígado, pulmão, rim e coração) provenientes de propriedades rurais com histórico de aborto. As amostras foram analisadas por Reação em Cadeia da Polimerase (PCR), Histopatologia (HP) e Imunohistoquímica (IHQ), com a finalidade de associar o abortamento a T. gondii e/ou N. caninum. Nenhuma amostra foi positiva na PCR e IHQ para T. gondii. Algumas amostras de cérebro, fígado, pulmão, rim e coração de fetos de caprinos e ovinos foram positivas na PCR para N. caninum. Na histopatologia foi observado leve infiltrado mononuclear no fígado e necrose com calcificação no SNC de um caprino, associada à imunomarcação positiva para N. caninum na IHQ e PCR positiva. Os resultados confirmam a transmissão vertical de N. caninum em caprinos naturalmente infectados na região nordeste do Brasil.(AU)

Assuntos

RESUMO

Toxoplasma gondii and Neospora caninum are causative agents of abortion in sheep and goats. Thus, the present study aimed to describe the transplacental transmission of these protozoans in small ruminants of northeastern Brazil. Seventeen fetuses (6 goats and 11 sheep) from farms with history of abortion were necropsied and samples were collected from different tissues (brain, liver, lung, kidney and heart). The samples were analyzed by PCR, histopathology (HP) and immunohistochemistry (IHC) to evaluate whether T. gondii and/or N. caninum infection were the cause of abortion. None of the samples was positive for T. gondii according to PCR and IHC results. Some brain, liver, lung, kidney and heart samples of goat fetuses were positive for N. caninum by PCR. In the histopathology, mild mononuclear infiltration and necrosis with calcification were observed in the liver and brain of one goat fetus, respectively, that also was positive for N. caninum by PCR and IHC. The results confirmed vertical transmission of N. caninum in naturally infected goats of northeastern, Brazil.(AU)

Toxoplasma gondii e Neospora caninum são reconhecidos como protozoário causadores de aborto em ovinos e caprinos. Desta forma, objetivou-se descrever a transmissão transplacentária desses agentes em pequenos ruminantes na região Nordeste do Brasil. Foram examinados seis fetos caprinos e onze fetos ovinos, totalizando 78 amostras de diferentes tecidos (cérebro, fígado, pulmão, rim e coração) provenientes de propriedades rurais com histórico de aborto. As amostras foram analisadas por Reação em Cadeia da Polimerase (PCR), Histopatologia (HP) e Imunohistoquímica (IHQ), com a finalidade de associar o abortamento a T. gondii e/ou N. caninum. Nenhuma amostra foi positiva na PCR e IHQ para T. gondii. Algumas amostras de cérebro, fígado, pulmão, rim e coração de fetos de caprinos e ovinos foram positivas na PCR para N. caninum. Na histopatologia foi observado leve infiltrado mononuclear no fígado e necrose com calcificação no SNC de um caprino, associada à imunomarcação positiva para N. caninum na IHQ e PCR positiva. Os resultados confirmam a transmissão vertical de N. caninum em caprinos naturalmente infectados na região nordeste do Brasil.(AU)

Assuntos