Spelling suggestions: "subject:"protozoa."" "subject:"orotozoa.""
151 |
Efeitos da levedura, monensina sódica e salinomicina na degradabilidade, digestibilidade, parâmetros ruminais e protozoários ciliados de novilhos Nelore arraçoados com dietas concentradas / Effects of the yeast, monensin and salinomycin in the degradability, digestibility, rumen parameters and ciliates protozoa in termination diet Nellore steersJosiane Hernandes Ortolan 13 January 2006 (has links)
Foram utilizados quatro Novilhos nelore, com peso vivo médio de 190 ± 32 kg, canulados no rúmen num experimento com delineamento Quadrado Latino 4x4, onde o objetivo do trabalho foi avaliar o efeito da levedura, monensina e salinomicina sobre os parâmetros ruminais e o aparecimento de protozoários ciliados ruminais.O experimento foi executado no Campus Administrativo de Pirassununga, na Faculdade de Zootecnia e Engenharia de Alimentos da Universidade de São Paulo. A dieta oferecida aos animais foi composta por silagem de sorgo e concentrado (30:70), onde foram submetidos a quatro tratamentos diferidos de acordo com o aditivo usado, 5,0g de Levedura (Beef Sacc®), 0,42g de salinomicina (Coxistac®), 2,0g de monensina sódica (Rumensin®) e o controle sem aditivo. Os parâmetros avaliados foram degradabilidade ruminal, in situ do volumoso e da dieta total, concentração de ácidos graxos voláteis e nitrogênio amoniacal, pH ruminal, taxa de passagem líquida, turnover e volume ruminal, e identificação e contagem dos protozoários ciliados. O período experimental foi subdividido em vinte e um dias de adaptação e sete de colheita, totalizando vinte e oito dias por período experimental. Foram mensurados os coeficientes de degradabilidade nos períodos de incubação de 0, 3, 6, 12, 24, 48, 72 e 96 horas. Para a colheita de liquido ruminal foram utilizados os horários 0, 2, 4, 6, 8 horas; as colheitas de marcador de fase liquida (PEG) foram realizadas ás 0; 1,5; 3; 6; 12 e 24 horas após a alimentação. Houve aumento do valor para a fração b na MS, no tratamento levedura (p<0,05), e no tratamento salinomicina. Também houve uma tendência a aumentar a fração b no FDN. O tratamento levedura aumentou significativamente o número de protozoários ciliados no rúmen (p<0,05). Os valores referentes ao pH não foram afetados pelos tratamentos (p>0,05). A concentração de amônia e os valores encontrados para a cinética ruminal não foram afetados pelos tratamentos (p>0,05). O uso de ionóforos melhorou a proporção dos ácidos acético:propiônico, propiônico e butírico enquanto a levedura aumentou a concentração de acido acético (p<0,05). / Four Nelore Steers had been used, with average alive weight of 190 ± 32 kg, rumen cannulas, in an experiment with Squared delineation Latin 4x4, where the objective of the work was to evaluate the effect of the yeast culture, monensin and salinomycin on the rumen parameters and the appearance of ciliates protozoa. The experiment was executed in the Faculdade de Zootecnia e Engenharia de Alimentos of the Universidade de São Paulo. The diet offered to the animals was composed for ensilage and concentrated (30:70), where the four differed treatments had been submitted in accordance with the used additive, 5,0g of yeast culture (Beef Sacc), 0,42g of salinomycin (Coxistac), 2,0g of monensin (Rumensin) and the control without additive. The evaluated parameters had been ruminal degradability in situ of voluminous and the total diet, the concentration of volatile fatty acid concentration and ammoniac nitrogen concentration, pH ruminal, liquid passage, turnover and ruminal volume, and number and specie of ciliates protozoa. The experimental period was subdivided in twenty and one days of adaptation and seven of harvest, having totalized twenty and eight days for experimental period. The coefficients of degradability in the incubation periods of 0, 3, 6, 12, 24, 48, 72 and 96 hours had been measure. For the harvest of I eliminate ruminal had been used schedules 0, 2, 4, 6, 8 hours; the harvests of phase marker eliminate (PEG) had been carried through ace 0; 1,5; 3; 6; 12 and 24 hours after the feeding. It had increase of the value for fraction "b" in the MS, the treatment yeast culture, and the salinomycin treatment (p<0,05). Also it had a trend to increase fraction "b" in the FDN. The treatment yeast culture significantly increased the number of ciliates protozoa in rumen (p<0,05). The referring values to pH had not been affected by the treatments (p>0,05). The ammonia concentration and the values found for the kinetic ruminal had not been affected by the treatments (p>0,05). The use of ionophores improved the acid ratio of the acetic:propionic, propionic and butiric while the yeast culture increased the acids concentration of acetic (p<0,05).
|
152 |
Estudo do papel do ATP na ativação do sistema imune e na proteção durante a infecção por Plasmodium chabaudi. / Role of ATP in the immune response to blood-stage Plasmodium chabaudi malaria.Érika Machado de Salles 04 November 2011 (has links)
Estima-se que a malária seja responsável por um milhão de mortes anuais, atingindo principalmente crianças. O sistema imune participa tanto na proteção contra a infecção pelo plasmódio, como no desenvolvimento das síndromes associadas à malária (anemia, malária cerebral, acidose metabólica e choque sistêmico). Recentemente, tem sido mostrado que a imunidade inata é capaz de detectar sinais liberados por células ou tecidos danificados como o ATP e o ácido úrico. Esses sinais de perigo parecem ser importantes para promover a regulação da inflamação após o trauma ou injúrias ocasionadas pelos patógenos. Porém, a relevância fisiológica desses sinais na resposta imune e seu mecanismo de ação ainda não estão claros. Na malária, é provável que o ATP seja liberado no momento da ruptura dos eritrócitos, a partir de células danificadas do endotélio vascular ou de células do sistema imune mortas por ativação. Assim, neste estudo nós avaliamos o papel do ATP na ativação do sistema imune e no desenvolvimento da doença durante a infecção com P. chabaudi. Nossos resultados sugerem que, a concentração de ATP no soro e permeabilização de linfócitos do sangue é maior após a ruptura dos eritrócitos. Durante a infecção, as células T e as células dendríticas possuem uma capacidade exacerbada de resposta ao ATP, que pelo menos em parte depende do P2X7R. Além disso, a presença funcional de receptores purinérgicos parece ser importante para a fase inicial da resposta imune ao P. chabaudi. A inibição farmacológica do receptor reduziu o número de células, produção de IFN-<font face=\"Symbol\">g e injúria hepática. Desta forma a utilização do antagonistas do P2X7R poderia ser benéfico na resolução de problemas ocasionados pelo aumento acentuado do sistema imune. / It is estimated that malaria accounts for one million deaths annually, affecting mainly children. The immune system participates in both the protection against infection by the plasmodium, as in the development of the syndromes associated with malaria (anemia, cerebral malaria, metabolic acidosis and systemic shock). Recently, it has been shown that innate immune is able to detect signals released by damaged cells or tissues as ATP and uric acid. These danger signals appear to be important to promote the regulation of inflammation after trauma or injuries caused by pathogens. However, the physiological relevance of these signals in the immune response and its mechanism of action remain unclear. In malaria, it is likely that ATP is released upon rupture of erythrocytes, vascular endothelial cells damaged or dead cells of the immune system activation. In this study we evaluated the role of ATP in the activation of the immune system and the development of disease during infection with P. chabaudi. Our results suggest that ATP concentration serum and permeabilization of blood lymphocytes is higher after the rupture of erythrocytes. During infection T cells and dendritic cells have a heightened ability to respond to ATP which is partly dependent on P2X7R. Moreover, the presence of functional purinergic receptors appears to be important for the initial phase of the immune response to P. chabaudi. The pharmacological inhibition of the receptor reduced the number of cells, liver damage and IFN-<font face=\"Symbol\">g, thus the use of the P2X7 receptor antagonists could be beneficial in solving problems caused by the sharp increase in the immune system.
|
153 |
Taxonomia, morfologia e filogenia molecular de protistas ciliados (Ciliophora, Litostomatea) encontrados em ruminantes domésticosRossi, Mariana Fonseca 27 February 2013 (has links)
Submitted by Renata Lopes (renatasil82@gmail.com) on 2016-05-13T11:25:32Z
No. of bitstreams: 1
marianafonsecarossi.pdf: 3622749 bytes, checksum: 75680c20f0af5b48589dec0954c64298 (MD5) / Approved for entry into archive by Adriana Oliveira (adriana.oliveira@ufjf.edu.br) on 2016-06-27T20:09:03Z (GMT) No. of bitstreams: 1
marianafonsecarossi.pdf: 3622749 bytes, checksum: 75680c20f0af5b48589dec0954c64298 (MD5) / Made available in DSpace on 2016-06-27T20:09:03Z (GMT). No. of bitstreams: 1
marianafonsecarossi.pdf: 3622749 bytes, checksum: 75680c20f0af5b48589dec0954c64298 (MD5)
Previous issue date: 2013-02-27 / FAPEMIG - Fundação de Amparo à Pesquisa do Estado de Minas Gerais / A dissertação está dividida em três seções. A Seção 1 apresenta um estudo morfológico e taxonômico detalhado, no qual 36 espécies de ciliados do rúmen de bovino e ovino foram inventariadas, com base na observação dos ciliados in vivo, corados com preparações semipermanentes, impregnados pela técnica do carbonato de prata amoniacal e visualizados por microscopia eletrônica de varredura. Esta seção traz novas informações sobre os caracteres morfométricos importantes para a taxonomia deste grupo, com a descrição da infraciliatura e a importância do uso de técnicas ciliatológicas pouco usadas na caracterização de ciliados ruminais. Na Seção 2, com intuito de revelar a infraciliatura oral e somática para amplo espectro de gêneros e espécies de ciliados ruminais foram realizadas modificações nos protocolos existentes para a técnica do carbonato de prata amoniacal com piridina e estabelecido um protocolo modificado que permitiu a impregnação da infraciliatura oral e do aparato nuclear de todas as 36 espécies de ciliados do rúmen de bovino e ovino alimentados com cana-de-açúcar. O protocolo proposto é simples, rápido e fácil de ser reproduzido, sendo vantajoso para taxonomistas interessados em realizar estudos de levantamento de biota ruminal e para zootecnistas e ecólogos interessados em entender a estrutura da taxocenose de protistas ciliados ruminais. A Seção 3 apresenta um estudo filogenético da família Ophryoscolecidae com base em informações do gene 18S-rDNA, incluindo cinco novas sequências. Os principais resultados obtidos foram: ¹evidenciação da monofilia das subfamílias Entodiniinae e Ophryoscolecinae; ²a subfamília Diplodiniinae é considerada parafilética; ³os padrões de infraciliatura oral refletem divergência evolutiva na família Ophryscolecidae; 4evidenciação da monofilia dos padrões de ciliatura oral padrão-Entodinium, padrão Ostracodinium (Ostracodinium gracile e Ostracodinium mammosum), padrão-Epidinium e padrão-Ophryoscolex; 5a condição ancestral do padrão-Entodinium sugerida por alguns autores não pôde ser comprovada usando informações do gene 18S-rDNA. As incongruências observadas entre os dados morfológicos e moleculares refletem a necessidade de se ampliar o número de sequências do gene 18S-rDNA para representantes da família Ophryoscolecidae e investigar a evolução deste grupo usando outros marcadores moleculares. / The dissertation is divided into three sections. Section 1 provides a detailed taxonomic and morphological study, in which 36 species of rumen ciliates in cattle and sheep were inventoried, based on live observation, semipermanent preparations, pyridinated silver carbonate impregnation and scanning electron microscopy. This section provides new information on important morphometric characters for the taxonomy of this group, with the description of infraciliature and the importance of using techniques ciliatológicas underused in the characterization of rumen ciliates. In Section 2 aiming to reveal the somatic and oral infraciliature for wide spectrum of genera and species of rumen ciliates, were made modifications to existing protocols for the pyridinated silver carbonate impregnation and established a modified protocol that allowed allowed impregnation of infraciliatura oral and nuclear apparatus of all 36 species of rumen ciliates of cattle and sheep fed with cane sugar bagasse. The proposed protocol is simple, quick and easy to be reproduced, being advantageous for taxonomists interested in perform survey studies of ruminal biota and animal scientists and ecologists interested in understanding the taxocenose and structure of the rumen ciliates. Section 3 presents a phylogenetic study of the family Ophryoscolecidae based on 18S-rDNA gene information, including five new sequences. The main results were: ¹ confirmation of the monophyly of the Entodiniinae and Ophryoscolecinae subfamilies; 2 Diplodiniinae subfamily is considered paraphyletic; 3 oral infraciliature patterns reflect evolutionary divergence in the family Ophryscolecidae; 4 confirmation of monophyly of oral ciliature patterns Entodinium-type, Ostracodinium-type (Ostracodinium gracile and Ostracodinium mammosum), Epidinium-type and Ophryoscolex-type; 5 the ancestral condition of Entodinium-type suggested by some authors could not be verified using information from 18S-rDNA gene. The inconsistencies observed between the morphological and molecular data reflect the need to increase the number of 18S rDNA gene sequences to family Ophryoscolecidae representatives and investigate the evolution of this group using other molecular markers.
|
154 |
Detecção de anticorpos anti-Leishmania infantum, Neospora caninum e Toxoplasma gondii em cães necropsiados no hospital veterinário da UFSM / Detection of anti-Leishmania infantum antibody, Neospora caninum and Toxoplasma gondii in autopsied dogs in veterinary hospital UFSMRatzlaff, Fabiana Raquel 16 August 2016 (has links)
The dog (Canis lupus familiaris) can be infected by a variety of protozoa and may develop clinical signs or remain asymptomatic. Due to the proximity of this kind with the man some protozoa present zoonotic potential, as researchers studied, including Leishmania infantum, Neospora caninum and Toxoplasma gondii. L. infantum, it is responsible for causing visceral leishmaniasis in several species, including the dog and the man with deleterious impacts on public health. The dog is considered the urban reservoir of the parasite, and it is recommended the euthanasia of seropositive, including asymptomatic. N. caninum and T. gondii are widely distributed protozoa. These agents, when affecting dogs, can cause neurological, gastrointestinal, respiratory and muscle disturbs. N. caninum is a protozoan of great economic importance and may cause reproductive problems in farm animals and the dog is the definitive host of this agent. T. gondii is an opportunistic microorganism, a zoonotic potential, with world-occurrence. The dogs as well as humans, are considered intermediate hosts, infection may be more severe in pregnant women and immunocompromised individuals. This study aimed to research anti-Leishmania infantum antibodies, Neospora caninum and Toxoplasma gondii in autopsied dogs; and to determine the occurrence of infection in animals from Agudo, Jaguari, Júlio de Castilhos, Mata, Santa Maria, Santiago, São Martinho da Serra, São Vicente do Sul and Tupanciretã, towns in the central region of Rio Grande do Sul (RS). In addition, there were correlated epidemiological data on sex, age, race, origin and occurrence of these protozoa in the seasons, with the pathological lesions. The animals were necropsied during routine at Pathology Laboratory in the Universidade Federal de Santa Maria, from November 2014 to April 2016. For detection of seropositive dogs, the Indirect Immunofluorescence Antibody Test (IFAT) was performed on stored samples in serum bank Analysis Laboratory in Veterinary Clinics. It analyzed 78 samples, where 53/78 (67.9%) were seropositive, demonstrating the presence of antibodies to one or more of the agents in the population studied. The occurrence of antibodies to L. infantum, N. caninum and T. gondii was 26/78 (33.3%) 29/78 (37.1%) and 34/78 (43.5%) respectively. Mono infections observed in 5/53 (9.4%) of L. infantum, 10/53 (18.8%) to N. caninum and 11/53 (20.7%) T. gondii, while the coinfection appeared in 27/53 (50.9%) of the dogs were detected in 4/53 (7.5%) L. infantum + N. caninum, 8/53 (15.0%) L. infantum + T. gondii, 6/53 (11.3%) N. caninum + T. gondii and 9/53 (16.9%) L. infantum + N. caninum + T. gondii, affecting animals of different ages, without predominance sex or race. There were no pathological characteristic lesions, featuring animals as asymptomatic, indicating a role for these sentinels of dogs these diseases. This study contributed to a better understanding of the epidemiology of protozoa and noted the emergence of visceral leishmaniasis in animals from areas considered harmless. In addition, this work can support the public health services in the adoption of preventive measures, avoiding possible cases of autochthonous leishmaniasis in central RS. / O cão (Canis lupus familiaris) pode ser infectado por uma variedade de protozoários, podendo desenvolver sinais clínicos ou permanecer assintomático. Devido à proximidade desta espécie com o homem e por alguns protozoários apresentarem potencial zoonótico, se realizou um estudo, incluindo Leishmania infantum, Neospora caninum e Toxoplasma gondii. L. infantum, é responsável por causar a leishmaniose visceral em diversas espécies, abrangendo o cão e o homem, com impactos deletérios na Saúde Pública. O cão é considerado o reservatório urbano deste parasita, e recomenda-se a eutanásia dos soropositivos, inclusive os assintomáticos. N. caninum e T. gondii são protozoários de ampla distribuição geográfica. Estes agentes, quando acometem os cães, podem causar distúrbios neurológicos, gastrintestinais, respiratórios e musculares. N. caninum é um protozoário de grande importância econômica, podendo ocasionar problemas reprodutivos em animais de produção e o cão é o hospedeiro definitivo deste agente. T. gondii é um micro-organismo oportunista, de potencial zoonótico, com ocorrência mundial. Os cães, assim como o homem, são considerados hospedeiros intermediários, podendo a infecção ser mais grave em indivíduos imunocomprometidos ou gestantes. Este estudo teve por objetivo pesquisar anticorpos anti-Leishmania infantum, Neospora caninum e Toxoplasma gondii em cães necropsiados; bem como determinar a ocorrência da infecção em animais procedentes de Agudo, Jaguari, Júlio de Castilhos, Mata, Santa Maria, Santiago, São Martinho da Serra, São Vicente do Sul e Tupanciretã, municípios da região central do Rio Grande do Sul (RS). Adicionalmente, correlacionou-se os dados epidemiológicos referentes a sexo, idade, raça, procedência e a ocorrência destes protozoários nas estações do ano, com as lesões anatomopatológicas. Os animais foram necropsiados durante a rotina do Laboratório de Patologia da Universidade Federal de Santa Maria, no período de novembro de 2014 a abril de 2016. Para detecção dos cães sororreagentes, foi realizada a Reação de Imunofluorescência Indireta (RIFI), nas amostras armazenadas no banco de soro do Laboratório de Análises Clínicas Veterinárias. Analisou-se 78 amostras, onde 53/78 (67,9%) apresentaram soropositividade, demonstrando a presença de anticorpos para um ou mais dos agentes na população estudada. A ocorrência de anticorpos para L. infantum, N. caninum e T. gondii foi de 26/78 (33,3%), 29/78 (37,1%) e 34/78 (43,5%) respectivamente. Observou-se mono infecções em 5/53 (9,4%) para L. infantum, 10/53 (18,8%) para N. caninum e 11/53 (20,7%) para T. gondii, enquanto que, as coinfecções apareceram em 27/53 (50,9%) dos cães, sendo detectados em 4/53 (7,5%) L. infantum + N. caninum, 8/53 (15,0%) L. infantum + T. gondii, 6/53 (11,3%) N. caninum + T. gondii e 9/53 (16,9%) L. infantum + N. caninum + T. gondii, acometendo animais de diferentes idades, sem predominância de sexo ou raça. Não verificaram-se lesões anatomopatológicas características, caracterizando os animais como assintomáticos, denotando um papel para estes cães de sentinelas destas enfermidades. Este estudo contribuiu para um maior conhecimento da epidemiologia destas protozooses e observou o surgimento da leishmaniose visceral em animais provenientes de áreas consideradas indenes. Além disso, este trabalho poderá subsidiar os serviços de Saúde Pública na adoção de medidas preventivas, evitando possíveis casos de leishmaniose autóctones na região central do RS.
|
155 |
A survey of intestinal protozoa at the Stockton State Hospital : Stockton, CaliforniaGholz, Lawrence Melvin 01 January 1947 (has links) (PDF)
During the past months much has been published in periodicals, especially those of a pictorial nature, which discredits institutions established for the care of' the mentally ill throughout the nation. Many articles have been presented which show an intelligent approach, but the majority of these treatments are by those who are basing too much on a very narrow experience. For example, one news magazine recently printed a picture of a mental patient in institutional garb sitting on a bench in one of the poses most characteristic of a catatonic. The caption of the picture seemed to ignore this significant fact and instead to imply that the dejected pose was due to improper treatment. In this paper the author is neither defending the present mental institution, nor is he attempting to throw a "verbal brickbat" at the constructive work which is being done at institutions of this type. He is, rather, submitting an analysis of the prevalence and distribution of certain parasitic Protozoa in a large state hospital in the hope that the findings are of significance not merely in terms of institutional welfare but also in the more general terms of: (1) relationship between mental health and parasitic infections, and (2) regional differences in the incidence of such infections in California.
|
156 |
Literature Review: Coinfection in Young Ruminant Livestock—Cryptosporidium spp. and Its CompanionsDelling, Cora, Daugschies, Arwid 02 June 2023 (has links)
The protozoan Cryptosporidium parvum is one of the major causative pathogens of diarrhoea in young ruminants; therefore, it causes economic losses and impairs animal welfare. Besides C. parvum, there are many other non-infectious and infectious factors, such as rotavirus, Escherichia coli, and Giardia duodenalis, which may lead to diarrhoeic disease in young livestock. Often, more than one infectious agent is detected in affected animals. Little is known about the interactions bet-ween simultaneously occurring pathogens and their potential effects on the course of disease. In this review, a brief overview about pathogens associated with diarrhoea in young ruminants is presented. Furthermore, information about coinfections involving Cryptosporidium is provided.
|
157 |
Towards a Better Understanding of the Metabolism, Physiology, and Ecology of Rumen Protozoa: New Insights from Culturomics and GenomicsPark, Tansol January 2017 (has links)
No description available.
|
158 |
Métodos de recuperação e estimativa de viabilidade de cistos de Giardia spp. e oocistos de Cryptosporidium spp. em resíduos do tratamento de água de consumo / Recovery methods and viability assessment of Giardia spp. e oocistos cysts and Cryptosporidium spp. oocysts in water treatment residuesSilva, Kamila Jéssie Sammarro 25 February 2019 (has links)
Esta pesquisa comparou a incorporação de iodeto de propídio (IP) com a avaliação simultânea de corantes indicativos de danificação em membrana e atividade enzimática (Live/Dead Cell Assay®) para a estimar a viabilidade de cistos de Giardia muris e oocistos de Cryptosporidium parvum. Além disso, foram testados métodos de recuperação de (oo)cistos em amostras de lodo e água de lavagem de filtros (ALF) geradas em escala de bancada, simulando tratamento de água por ciclo completo com decantação. Dentre os métodos estudados para a detecção de G. muris e C. parvum inoculados em amostras de lodo, destacou-se a floculação com sulfato férrico, seguida de separação imunomagnética (IMS). Realizou-se, portanto, ensaio de qualidade analítica com ColorSeedTM, para este método, tendo atendido ao requerido pelo Método 1623.1 da USEPA (2012) para Giardia spp. (32,25%; CV=9,00%), mas não tendo sido suficiente para Cryptostoridium spp. (11,00%; CV=47,67%). O teste com ColorSeedTM em amostras de ALF reproduziu o procedimento de filtração em membrana (FM) com raspagem utilizando Tween® 80 (45°C, 0,1%) seguido de IMS, tendo atendido ao Método 1623.1 para Giardia spp. (13,00%, CV=19,61%), mas não tendo sido suficiente para Cryptostoridium spp. (2,00%; CV=93,54%). Optou-se por este procedimento na avaliação de qualidade analítica, pois o inóculo prévio de suspensões comerciais seguido de recuperação por FM sem IMS superou 100% para C. parvum, devido à utilização de fator de multiplicação. O desempenho do Live/Dead Cell Assay® sobre suspensões comerciais de (oo)cistos foi subjetivo, sobretudo para visualização de organismos enzimaticamente ativos, de modo que optou-se pela inclusão de IP como parâmetro para estimar o efeito dos métodos de recuperação sobre a viabilidade. Em função da baixa recuperação e fluorescência de G. muris, a incorporação de IP foi avaliada apenas em C. parvum. Os resultados reiteraram a dificuldade na recuperação de protozoários em lodo e ALF e o fato de que as particularidades destes procedimentos analíticos podem prejudicar a interpretação de dados de viabilidade. / This study compared the incorporation of propidium iodide (PI) with the simultaneous evaluation of dyes that indicate both membrane damage and enzymatic activity (Live/Dead Cell Assay®) to assess the viability of Giardia muris cysts and Cryptosporidium parvum oocysts. In addition, methods of recovering protozoan cysts and oocysts from sludge and filter backwash water (FBW) samples generated on bench scale, simulating conventional water treatment with decantation, were tested. Among the studied methods for detection of G. muris and C. parvum spiked into sludge samples, ferric sulphate flocculation followed by immunomagnetic separation (IMS) lead to higher recoveries. An analytical quality assay was therefore carried out with ColorSeedTM having met the USEPA Method 1623.1 (2012) recommendation for Giardia spp. (32.25%, CV=9.00%) but not for Cryptostoridium spp. (11.00%, CV = 47.67%). The quality assay test for FBW samples replicated the membrane filtration (MF) procedure using Tween® 80 (45 °C, 0.1%) followed by IMS, having complied with Method 1623.1 for Giardia spp. (13.00%, CV=19.61%) but again not for Cryptostoridium spp. (2.00%; CV=93.54%). This procedure was chosen for the analytical quality exam, since the previous inoculum of commercial suspensions followed by MF without IMS exceeded 100% recovery for C. parvum, due to the use of a multiplication factor. The Live/Dead Cell Assay® performance on commercial suspensions of cysts and oocysts was subjective, especially for visualizing enzymatically active organisms, thus PI inclusion was chosen as the parameter to estimate the effect of recovery methods on the organisms\' viability. Due to the low recovery and poor fluorescence of G. muris, IP inclusion was evaluated only in C. parvum. The results reiterated the difficulty in the recovery of protozoa from sludge and FBW and the possibility of these analytical procedures hinder the interpretation of cysts and oocysts viability.
|
159 |
Avaliação e tratamento da água de lavagem dos filtros e dos resíduos sedimentados gerados pela tecnologia de ciclo completo contendo oocistos de Cryptosporidium spp. e cistos de Giardia spp. / Evaluation and treatment of water treatment plants backwashing water and sedimented residue with Cryptosporidium spp. oocysts and Giardia spp. cystsOgura, Allan Pretti 27 February 2018 (has links)
Os oocistos de Cryptosporidium spp. e os cistos de Giardia spp. podem gerar doenças de veiculação hídrica associadas a problemas de saúde pública. Os (oo)cistos são de difícil remoção e inativação durante o tratamento de água, principalmente devido ao tamanho reduzido e à resistência ao processo de cloração. Além disso, os métodos de detecção de protozoários na água apresentam elevado custo e estão sujeitos à grande variabilidade e à baixa reprodutibilidade, especialmente em águas de elevada turbidez. Com água de estudo com turbidez de aproximadamente 110 uT, ensaios de tratabilidade com cloreto de polialumínio foram feitos em jarteste para a obtenção da água de lavagem dos filtros (ALF) e do resíduo sedimentado. O método escolhido para detecção de (oo)cistos foi a centrifugação direta com adição de solução de dispersão ICN 7X seguido de IMS com duas dissociações ácidas (CD + ICN 7X). O tratamento dos resíduos objetivou a inativação dos (oo)cistos, por meio de danos à estrutura celular dos parasitos, identificada pela incorporação do corante iodeto de propídio no microrganismo. Para o método CD + ICN 7X, menor interferência na viabilidade dos (oo)cistos foi observada em relação à floculação em carbonato de cálcio e melhor recuperação do que a centrifugação direta. O controle de qualidade analítica desse método, feito com suspensão do kit EasySeed®, apresentou recuperação de 2,8±0,8% de oocistos e 7,8±2,9% de cistos para a ALF e de 3,3±2,0% e 24,8±8,0%, para oocistos e cistos no resíduo sedimentado. Apenas a recuperação de cistos de Giardia spp. no resíduo sedimentado atendeu aos padrões recomendados pelo Método 1623.1 da USEPA. A presença de microesferas magnéticas aderidas aos (oo)cistos foi observada nos poços de leitura após a IMS, indicando limitações desse método de purificação. Para o tratamento alcalino do resíduo sedimentado, a dosagem de 27mg/100mL foi testada para os tempos de 3 e 5 dias e, respectivamente, foram obtidos 1,85 e 3,0 log de inativação de oocistos e 2,05 e 2,14 log de inativação para cistos. Para o processo de ozonização da ALF, avaliado apenas para oocistos, as inativações de 2,83 log e 3,44 log foram obtidas para as dosagens de 7,5 mg O3 L-1 por 10 min e 10 mg O3 L-1 por 5 min, respectivamente. / Cryptosporidium spp. oocysts and Giardia spp. cysts are infectious forms and can cause public health problems due to associated waterborne diseases. (Oo)cysts are difficult to remove and inactivate during water treatment, mainly because of reduced size and resistance to chlorination. In addition, protozoan detection methods in water are expensive and subject to high variability and low reproducibility, especially in high turbidity water. In jartest treatability tests, 110 uT study water was treated with polyaluminium chloride to obtain backwashing water (BW) and sedimented residue. The method chosen for detection of (oo)cysts was direct centrifugation with addition of 7X ICN dispersion solution followed by IMS with two acid dissociations. Treatment of residuals objectified inactivation of (oo)cysts by damages on parasites cellular structure, identified by inclusion of propidium iodide as an indicator. The method of detection chosen showed less interference in the viability of (oo)cysts in comparison to flocculation in calcium carbonate and better recovery than direct centrifugation. The analytical quality control of this method, performed with EasySeed® suspension, obtained recovery of 2.8±0.8% oocysts and 7.8±2.9% cysts for BW and of 3.3±2.0% and 24.8±8.0%, for oocysts and cysts in sedimented residue. Only Giardia spp. recovery in sedimented residue complied with the standards recommended by USEPA Method 1623.1. Magnetic microspheres were found attached to (oo)cysts in microscope slides after IMS, indicating limitations of this purification method. For the alkaline treatment of sedimented residue, dosage of 27mg / 100mL was tested for 3 and 5 days and respectively 1.85 and 3.0 log inactivation were obtained for oocysts while 2.05 and 2.14 log of. For ozonation of BW, evaluated only for oocysts, 2.83 log and 3.44 log inactivation were obtained for dosages of 7.5 mg O3 L-1 for 10 min and 10 mg O3 L-1 for 5 min, respectively.
|
160 |
Neospora caninum : studies toward isolation in New Zealand : a thesis presented in partial fulfilment of the requirements for the degree of Master of Veterinary Studies at Massey University, Palmerston North, New ZealandWalton, Julie K January 2008 (has links)
Background: Neospora caninum is a parasite that causes disease, largely in cattle and dogs. It is a disease of significant interest within New Zealand due to its association with bovine abortion. The economic impact of bovine abortion justifies the development of a bovine vaccine against N. caninum. Aim: To develop and optimise diagnostic procedures for the detection of Neospora from a variety of blood and tissue samples and to isolate a New Zealand strain of Neospora caninum. Methods: A local strain of Toxoplasma gondii and an imported Neospora caninum strain, Nc-Liverpool, were used to optimise tachyzoite growing conditions in bovine endothelial (BE) cells and Vero host cell cultures. A serum study using 112 tissue culture flasks was performed to determine whether foetal bovine serum or horse serum supplemented media provided the optimal growing conditions for Nc-Liverpool tachyzoites. Nc-Liverpool tachyzoites were also used to determine the optimal growth period between passage, and harvest for cryopreservation and cryopreservation conditions. Percoll gradients were also tested using Nc-Liverpool tachyzoites. A known Neospora positive canine sample and murine tissues infected with Toxoplasma, were used during the development of the immunohistochemical diagnostic technique. Antibody concentrations and incubation temperatures were tested to reduce cross-reactivity and increase specific stain intensity. Immunohistochemistry was performed on sections of all tissue samples used for N. caninum isolation and experimentally infected murine tissue. Several PCR techniques were developed, the final PCR used being a combination of the different techniques, which produced a 250kb band. PCR-3 used the NF6/GA1 primer combination for Neospora detection and TF6/GA1 for Toxoplasma detection, additional Mg2+ and an annealing temperature of 55°C were required. Whole tissue was processed via DNA elution whereas cell culture and Percoll purified tachyzoites were used following crude lysis techniques. All bovine and canine tissues used for parasite isolation as well as all experimentally infected mouse tissues were tested for N. caninum using PCR. An immunoblot technique was developed for the detection of N. caninum antibodies in murine blood samples. Lysed Nc-Liverpool tachyzoites were used as antigen with varied results. The primary and secondary antibodies were commercially available and used at concentrations of 1:1,000 and 1:25,000 respectively. BALB/c and CF1 mice were experimentally infected with Toxoplasma gondii and Nc-Liverpool. Forty female BALB/c and 40 female CF1 mice were used in 2 studies to determine the optimal Nc-Liverpool inoculation dose and immunosuppression requirements. Mice were immunosuppressed with 2.5mg of methylprednisolone acetate (MPA) and Nc-Liverpool inoculation ranged from 1.3x106 to 5x103 tachyzoites. Upon death, the brain and blood was harvested from the mouse carcases. Attempts were made to isolate a New Zealand strain of N. caninum from bovine and canine central nervous system (CNS) tissue, and to maintain the parasites in cell culture and by small animal passage, in order to attenuate the parasite strain for use as a live large animal vaccine. Twenty one bovine tissue samples were used for N. caninum isolation attempts, 18 of which were positive for Neospora antibodies using a commercial IFAT. Isolation tissues were purified using a 30% Percoll gradient and inoculated onto 8 cell culture flasks and into 8 immunosuppressed mice (BALB/c and CF1). Results: Nc-Liverpool tachyzoites were found to be viable when grown at 37°C in antibiotic-MEM supplemented with either FBS or ES and grew optimally in FBS despite Neospora antibodies being detected using an IFAT. Passaging cultures at approx. 4 day intervals resulted in the greatest parasite growth. However, cryopreserved parasites should be harvested 2 days post inoculation (PI) for optimal viability. Viable parasites could be isolated using a 30% Percoll gradient and centrifuged at 2,700 x g (3,400 rpm) in a bucket centrifuge for 10 minutes. Tissue cysts could be detected using immunohistochemistry but some degree of cross reaction remained despite optimisation. Cysts were not found in tissues used for isolation attempts or in mouse brains following inoculation with Nc-Liverpool, however cysts were commonly found in mice experimentally infected with T. gondii tachyzoites. PCR-3 was successfully used to detect N. caninum and T. gondii infected tissue and tachyzoites from tissue culture. PCR-3 could detect N. caninum DNA in the brain tissue of 9/24 mice experimentally infected with Nc-Liverpool, even though most mice were culled within 1 week. Although production of N. caninum antigen was only moderately successful, N. caninum antibody detection in mouse blood using one specific antigen batch was reliable and specific. The immunoblot could only detect N. caninum antibody approximately 14 days PI, but was sensitive enough to detect 100% of mice experimentally infected with Nc-Liverpool tachyzoites. PCR-3 strongly correlated with the immunoblot results from 14 days PI. BALB/c mice were found to be far more sensitive to Nc-Liverpool than CF1 mice and developed severe disease at concentrations of approximately 1x106 Nc-Liverpool tachyzoites. Neither BALB/c nor CF1 mice developed peritoneal exudate, irrespective of the parasite inoculation concentration. Despite Neospora DNA being present in the brains of experimentally infected mice, re-isolation and continuous parasite passage from the brains could not be achieved. No mice experimentally infected with either Nc-Liverpool or isolation attempts were found to have brain cysts when tested using immunohistochemistry. Only 1 mouse inoculated with bovine isolation material was found to have a Neospora positive PCR. Through the detection of DNA, antigens and antibodies, parasites were determined to have been present in 10 of the 18 IFAT positive bovine isolation samples, indicating that 55% of calves born to seropositive dams were infected with N. caninum. However, despite numerous attempts to isolate Neospora parasites from naturally infected canine and bovine tissue and culturing using the optimised Nc-Liverpool technique, maintenance of a live culture of a New Zealand strain of N. caninum could not be established. Conclusions: Findings from this study could be used to assist in the maintenance of Neospora caninum and Toxoplasma gondii parasite strains and for detection or diagnosis of these parasites in host tissues.
|
Page generated in 0.5328 seconds