BACKGROUND: Hysterectomies are one of the most frequently performed surgical procedures in the United States. There are a wide variety of diagnoses that require a patient to obtain this procedure, but the majority of hysterectomies are performed for benign indications. Currently, gynecologists do not follow a standardized protocol surrounding postoperative laboratory ordering, and healthcare professionals can order a wide range of tests as often as they choose. Extraneous laboratory orders are disruptive to the patients’ well-being and risk their health following surgery. These orders are costly for hospital systems, take up precious time of hospital employees, and influence the course of patient treatment only in extremely rare circumstances. There are few studies that develop exclusion criteria for patients who may not require a laboratory test following surgery. Though systems to predict postoperative hematocrit have been created, they are complicated and difficult to use. The few studies that were performed are yet to be accepted by the medical community, in part because of their limited scope. This study will be the first to incorporate the results of robotic surgery in the analysis. OBJECTIVE: The purpose of this study is to determine concrete parameters to indicate that a patient is in need of postoperative laboratory work and at risk for anemia or transfusion. We aim to develop two comprehensive models that guide surgical practitioners to identify the cases which do not require laboratory data. METHODS: A total of 1027 gynecologic surgeries were performed at Saint Francis Hospital and Medical Center between April 1, 2014 and May 31, 2016. This retrospective study extracted data from EPIC EMR according to 42 variables preconceived to be the leading indicators of postoperative hematocrit and overall healing. Five healthcare professionals were surveyed to identify the variables that influence their postsurgical patient assessments and their decisions to order blood testing. This information was developed into score sheets with differing levels of stringency. Correlation highlighted 14 of the initial 42 variables as contributors to postoperative hematocrit and an equation model was built. Stepwise linear regression was used for univariate and multivariate analyses, from which we created our equation to predict all patients’ postoperative hematocrit. RESULTS: Out of the 1027 initial cases, a total of 602 cases were identified as hysterectomies for benign indications. Survey data gave the highest value to urine output and heart rate as key indicators of postoperative anemia. From the survey data, two clinical scoring sheets with differing stringency were created to guide practitioner laboratory ordering. These sheets gave parameters of heart rate and urine output the largest correlative weight in determining postoperative hematocrit. However, based on regression analysis, parameters of age (AGE), body mass index (BMI), preoperative platelet count (PPC), estimated blood loss during surgery (IO EBL), preoperative hematocrit (PHCT) and postoperative fluid bolus orders (POSTOP FB) proved to be the key variables impacting postoperative hematocrit (POSTOP HCT). These items were translated into the equation: POSTOP HCT = 22.51 – 0.40*POSTOP FB – 0.01*IO EBL + 0.25 PHCT + 0.09*BMI + 0.06*AGE – 0.01*PPC (R-squared = 0.310). CONCLUSIONS: This study aims to decrease superfluous laboratory testing, as well as to contribute to a larger conversation considering the potential merits of clinical judgement in a data-driven healthcare system. We have created a number of comparable strategies in order to reduce the number of unnecessary blood draws: two clinical scoring sheets and an equation. The score sheets indicate when to order additional testing. These sheets are representative of a range of surgical practitioners’ conventional clinical judgement. The equation serves as an evidence-based guide for determining postoperative hematocrit following benign gynecologic surgery. These predictive mechanisms will be validated and a superior method determined as our research continues with prospective application. We eventually expect to use the most accurate mechanism to reduce postoperative blood testing following all surgeries.

Made available in DSpace on 2014-06-11T19:31:11Z (GMT). No. of bitstreams: 0 Previous issue date: 2009-01-30Bitstream added on 2014-06-13T19:41:09Z : No. of bitstreams: 1 capua_mlb_dr_jabo.pdf: 641370 bytes, checksum: 71b19a28f172b3515a32ed7c27977d96 (MD5) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / Dezoito cães com diagnóstico citopatológico e/ou histopatológico de linfoma foram avaliados quanto às alterações clínicas e clinico-patológicas. Os animais foram submetidos ao protocolo quimioterápico de Madison-Wisconsin e avaliados clinicamente a cada sessão de quimioterapia quanto à sua resposta ao tratamento. Cinqüenta por cento dos cães apresentaram a forma multicêntrica da doença e 33% a forma cutânea. A manifestação clínica mais comum foi a linfadenomegalia superficial, acompanhada dos sinais sistêmicos de hiporexia, apatia e perda de peso. As principais alterações hematólogicas foram anemia normocítica normocrômica, trombocitopenia e leucocitose, associadas às síndromes paraneoplásicas. Elevações nas atividades séricas de lactato desidrogenase foram observadas em 58% dos cães e a hiperproteinemia ocorreu em 38% dos animais, sendo atribuída principalmente ao aumento de globulinas séricas. Vinte e sete por cento dos animais atingiram remissão completa da doença e 33% atingiram sobrevida de seis meses. Houve correlação positiva entre o valor do hematócrito e o tempo de sobrevida para os cães que morreram, entretanto, o mesmo não foi observado para o valor de lactato desidrogenase. Sugere-se a ocorrência da síndrome da lise tumoral aguda para sete animais dado o intervalo de tempo observado entre a quimioterapia e o óbito e o avançado estágio da doença. A ausência de resposta às tentativas de reindução da remissão, observada em quatro cães, pode estar relacionada com o fenômeno de resistência tumoral aos agentes quimioterápicos. / Clinical and laboratorial evaluation were performed in eighteen dogs with cytopathological and/or histopathological lymphoma diagnosis. Animals underwent the Madison-Wisconsin chemotherapy protocol and were evaluated clinically at each session performed weekly. The multicentric and cutaneous forms of the disease were observed in 50% and 33% of the dogs, respectively. The most common clinical sign was superficial lymphadenomegaly, combined to systemic signs of hyporexia, apathy and weight loss. The main hematological changes were anemia, thrombocytopenia and leukocytosis, associated with paraneoplastic syndromes. Elevated serum activity of lactate dehydrogenase was observed in 58% of the dogs and hyperproteinemia in 38%, attributed to serum globulin increase. Complete remission was achieved in 27% of the animals and the six-month survival rate was 33%. There was a positive correlation between the hematocrit and survival time in dogs that died, however, there was no correlation between lactate dehydrogenase and survival time. The time interval between chemotherapy and death and the advanced stage of the disease in seven animals suggest the occurrence of acute tumor lysis syndrome. The absence of response to attempts of remission reinduction in four animals may be related to the drug tumoral resistance effect.

Made available in DSpace on 2014-06-11T19:27:58Z (GMT). No. of bitstreams: 0 Previous issue date: 2011-06-22Bitstream added on 2014-06-13T19:36:20Z : No. of bitstreams: 1 dorigam_jp_me_jabo.pdf: 153030 bytes, checksum: 4491395fa8beb120ea5568cea9c80761 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / O hemograma, amplamente utilizado na medicina veterinária por apresentar praticidade e baixo custo, é rotineiramente solicitado para o diagnóstico de diversas enfermidades que acometem os animais de companhia, bem como para o acompanhamento destes pacientes. Faltam estudos que reflitam a realidade que os laboratórios enfrentam: as amostras recebidas, pertencentes a animais enfermos, nem sempre podem ser processadas na hora, podendo ficar armazenada por horas. Paralelamente a essa situação, a doença renal crônica é a afecção renal mais comum em cães e gatos, que acabam necessitando de acompanhamento clínico e, para tanto, o hemograma é uma das ferramentas utilizadas. Além disso, a DRC possui consequências diretas no sangue do paciente. Diante deste problema, realizou-se este ensaio com o fito de analisar a estabilidade de alguns dos parâmetros do hemograma, de amostras retiradas de pacientes em diferentes estágios de doença renal crônica, e estocadas a diferentes temperaturas e tempos. Foram utilizados 24 animais da rotina clínica. O sangue foi coletado, processado e então armazenado para posteriores contagens de hemácias, leucócitos e plaquetas, assim como a determinação do volume globular, concentração de hemoglobina, volume corposcular médio, hemoglobina corpuscular média, concentração de hemoglobina corpuscular média, contagem diferencial de leucócitos em esfregaços sanguineos e contagem de reticulócitos. Desta forma, o sangue foi distribuido em duas frações, armazenadas a 4°C e a 25°C e analisadas logo após a coleta, e então passadas quatro, oito, vinte e quatro, quarenta e oito e setenta e duas horas. Os resultados corroboraram com experimentos anteriores realizados com cães hígidos. Foi possível observar que, apesar do sangue urêmico provocar menor viabilidade celular in vivo, os resultados não foram... / The complete blood count, widely used in veterinary medicine by presenting practicality and low cost, is routinely requested for diagnosis of various diseases that affect pets, as well as monitoring these patients. There is a lack of studies that reflect the reality that laboratories face: the samples, deriving from sick animals, can't always be processed as they are received, and may be stored for hours. Parallel to this, chronic kidney disease is the most common kidney illness in dogs and cats that end up needing clinical follow-up and, therefore, the CBC is one of the tools used. In addition, the CKD has direct consequences on the patient's blood. Faced with this problem, this test was carried out with the aim of analyzing the stability of some of the parameters of the CBC, in samples taken from patients at different stages of chronic kidney disease, and stored at different temperatures and times. 24 animals from the clinical routine were used. Blood was collected, processed and then stored for later counts of red blood cells, white cells and platelets, as well as packed cell volume, hemoglobin concentration, mean corpuscular volume, mean corpuscular hemoglobin, mean corpuscular hemoglobin concentration, leukocyte count in blood smears, and reticulocyte count. Thus, the blood was distributed in two fractions, stored at 4°C and 25°C and analyzed immediately after collection, and then after four, eight, twenty-four, forty-eight and seventy-two hours. The results corroborate previous experiments carried out on healthy dogs. It was observed that despite that uremic blood lead to lower cell viability in vivo, the results were not significantly different from works carried out on healthy animals, thereby remaining the ideal time of storage to carry out laboratory tests up to eight hours at room temperature (25°C) and up to forty eight hours under refrigeration temperature (4°C)

Orientador: Aureo Evangelista Santana / Banca: Márcia Ferreira da Rosa Sobreira / Banca: Raimundo Souza Lopes / Resumo: O hemograma, amplamente utilizado na medicina veterinária por apresentar praticidade e baixo custo, é rotineiramente solicitado para o diagnóstico de diversas enfermidades que acometem os animais de companhia, bem como para o acompanhamento destes pacientes. Faltam estudos que reflitam a realidade que os laboratórios enfrentam: as amostras recebidas, pertencentes a animais enfermos, nem sempre podem ser processadas na hora, podendo ficar armazenada por horas. Paralelamente a essa situação, a doença renal crônica é a afecção renal mais comum em cães e gatos, que acabam necessitando de acompanhamento clínico e, para tanto, o hemograma é uma das ferramentas utilizadas. Além disso, a DRC possui consequências diretas no sangue do paciente. Diante deste problema, realizou-se este ensaio com o fito de analisar a estabilidade de alguns dos parâmetros do hemograma, de amostras retiradas de pacientes em diferentes estágios de doença renal crônica, e estocadas a diferentes temperaturas e tempos. Foram utilizados 24 animais da rotina clínica. O sangue foi coletado, processado e então armazenado para posteriores contagens de hemácias, leucócitos e plaquetas, assim como a determinação do volume globular, concentração de hemoglobina, volume corposcular médio, hemoglobina corpuscular média, concentração de hemoglobina corpuscular média, contagem diferencial de leucócitos em esfregaços sanguineos e contagem de reticulócitos. Desta forma, o sangue foi distribuido em duas frações, armazenadas a 4°C e a 25°C e analisadas logo após a coleta, e então passadas quatro, oito, vinte e quatro, quarenta e oito e setenta e duas horas. Os resultados corroboraram com experimentos anteriores realizados com cães hígidos. Foi possível observar que, apesar do sangue urêmico provocar menor viabilidade celular in vivo, os resultados não foram ... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The complete blood count, widely used in veterinary medicine by presenting practicality and low cost, is routinely requested for diagnosis of various diseases that affect pets, as well as monitoring these patients. There is a lack of studies that reflect the reality that laboratories face: the samples, deriving from sick animals, can't always be processed as they are received, and may be stored for hours. Parallel to this, chronic kidney disease is the most common kidney illness in dogs and cats that end up needing clinical follow-up and, therefore, the CBC is one of the tools used. In addition, the CKD has direct consequences on the patient's blood. Faced with this problem, this test was carried out with the aim of analyzing the stability of some of the parameters of the CBC, in samples taken from patients at different stages of chronic kidney disease, and stored at different temperatures and times. 24 animals from the clinical routine were used. Blood was collected, processed and then stored for later counts of red blood cells, white cells and platelets, as well as packed cell volume, hemoglobin concentration, mean corpuscular volume, mean corpuscular hemoglobin, mean corpuscular hemoglobin concentration, leukocyte count in blood smears, and reticulocyte count. Thus, the blood was distributed in two fractions, stored at 4°C and 25°C and analyzed immediately after collection, and then after four, eight, twenty-four, forty-eight and seventy-two hours. The results corroborate previous experiments carried out on healthy dogs. It was observed that despite that uremic blood lead to lower cell viability in vivo, the results were not significantly different from works carried out on healthy animals, thereby remaining the ideal time of storage to carry out laboratory tests up to eight hours at room temperature (25°C) and up to forty eight hours under refrigeration temperature (4°C) / Mestre

Resumo: Dezoito cães com diagnóstico citopatológico e/ou histopatológico de linfoma foram avaliados quanto às alterações clínicas e clinico-patológicas. Os animais foram submetidos ao protocolo quimioterápico de Madison-Wisconsin e avaliados clinicamente a cada sessão de quimioterapia quanto à sua resposta ao tratamento. Cinqüenta por cento dos cães apresentaram a forma multicêntrica da doença e 33% a forma cutânea. A manifestação clínica mais comum foi a linfadenomegalia superficial, acompanhada dos sinais sistêmicos de hiporexia, apatia e perda de peso. As principais alterações hematólogicas foram anemia normocítica normocrômica, trombocitopenia e leucocitose, associadas às síndromes paraneoplásicas. Elevações nas atividades séricas de lactato desidrogenase foram observadas em 58% dos cães e a hiperproteinemia ocorreu em 38% dos animais, sendo atribuída principalmente ao aumento de globulinas séricas. Vinte e sete por cento dos animais atingiram remissão completa da doença e 33% atingiram sobrevida de seis meses. Houve correlação positiva entre o valor do hematócrito e o tempo de sobrevida para os cães que morreram, entretanto, o mesmo não foi observado para o valor de lactato desidrogenase. Sugere-se a ocorrência da síndrome da lise tumoral aguda para sete animais dado o intervalo de tempo observado entre a quimioterapia e o óbito e o avançado estágio da doença. A ausência de resposta às tentativas de reindução da remissão, observada em quatro cães, pode estar relacionada com o fenômeno de resistência tumoral aos agentes quimioterápicos. / Abstract: Clinical and laboratorial evaluation were performed in eighteen dogs with cytopathological and/or histopathological lymphoma diagnosis. Animals underwent the Madison-Wisconsin chemotherapy protocol and were evaluated clinically at each session performed weekly. The multicentric and cutaneous forms of the disease were observed in 50% and 33% of the dogs, respectively. The most common clinical sign was superficial lymphadenomegaly, combined to systemic signs of hyporexia, apathy and weight loss. The main hematological changes were anemia, thrombocytopenia and leukocytosis, associated with paraneoplastic syndromes. Elevated serum activity of lactate dehydrogenase was observed in 58% of the dogs and hyperproteinemia in 38%, attributed to serum globulin increase. Complete remission was achieved in 27% of the animals and the six-month survival rate was 33%. There was a positive correlation between the hematocrit and survival time in dogs that died, however, there was no correlation between lactate dehydrogenase and survival time. The time interval between chemotherapy and death and the advanced stage of the disease in seven animals suggest the occurrence of acute tumor lysis syndrome. The absence of response to attempts of remission reinduction in four animals may be related to the drug tumoral resistance effect. / Orientador: Aureo Evangelista Santana / Coorientadora: Ana Paula Massae Nakage Canesin / Banca: Renée Laufer Amorim / Banca: Sílvia Ricci Lucas / Banca: Márcia Ferreira da Rosa Sobreira / Banca: Carlos Roberto Daleck / Doutor

The majority of laboratory testing errors originate in the pre-analytical phase. While the causes and frequencies of pre-analytical errors are well characterized, there are few studies investigating the cost of these errors. The objective of this research was to build a model to quantify the cost of pre-analytical errors occurring during inpatient complete blood count (CBC) testing at Sunnybrook Health Sciences Centre (Sunnybrook). The resultant cost model accounts for the costs of materials, resources, and personnel-time consumed in the CBC testing process. In 2011, pre-analytical errors in inpatient CBC testing cost Sunnybrook $43,462, and represented a loss of 775 employee hours due to laboratory test repetition and error-related activities. This cost model represents the minimum cost of a pre-analytical error, as costs extraneous to the laboratory were beyond the study scope. Future studies investigating downstream effects of pre-analytical errors and the costs associated with them should be conducted.

The majority of laboratory testing errors originate in the pre-analytical phase. While the causes and frequencies of pre-analytical errors are well characterized, there are few studies investigating the cost of these errors. The objective of this research was to build a model to quantify the cost of pre-analytical errors occurring during inpatient complete blood count (CBC) testing at Sunnybrook Health Sciences Centre (Sunnybrook). The resultant cost model accounts for the costs of materials, resources, and personnel-time consumed in the CBC testing process. In 2011, pre-analytical errors in inpatient CBC testing cost Sunnybrook $43,462, and represented a loss of 775 employee hours due to laboratory test repetition and error-related activities. This cost model represents the minimum cost of a pre-analytical error, as costs extraneous to the laboratory were beyond the study scope. Future studies investigating downstream effects of pre-analytical errors and the costs associated with them should be conducted.

Pyometra is an infectious disease predominating in adult female dogs during diestrus. It is caused by an intra uterine bacterial infection leading from a mild to a severe bacteremia and toxemia. In hematological parameters a severe leukocytosis and anemia usually are presents. The objective of this study was to evaluate complete blood count, neutrophil oxidative metabolism by nitroblue tetrazolium test (NBT) and lipid peroxidation using thiobarbituric acid reactive substances assay (TBARS). Twenty adult female dogs from 2 to 14 years old were used. All animals were allocated in two different groups. In group 1 E. coli pyometra diagnosed animals (n=12) and in group 2 only clinically healthy female dogs (n=8). There were significant lower values in red blood cell, packed cell volume and hemoglobin in group 1 animals than those in group 2 (control). A significant increase in total plasma protein and total leukocytes (segmented and band neutrophils and monocytes) occurred in group 1 when comparing to control. In NBT there was also an increase in group 1. But TBARS did not show a significant difference between groups. These results evidenced that adult female dogs with pyometra by E.coli show a normocyitic normocromic anemia and leukocytosis characterized by neutrophilia with a left shift. The NBT raise only indicate a neutrophil activity increased. / Piometra é uma doença que ocorre com maior freqüência em cadelas adultas durante o diestro. É causada por uma infecção bacteriana intra-uterina que resulta em bacteremia e toxemia discretas a intensas, determinando uma série de alterações sistêmicas. Os parâmatros hematológicos geralmente revelam acentuada leucocitose e anemia. Objetivando-se avaliar o hemograma, o metabolismo oxidativo dos neutrófilos, pelo teste de redução do tetrazólio nitroazul (NBT) e a peroxidação lipídica por meio da mensuração da concentração dos produtos de reação com o ácido tiobarbitúrico (TBARS), foram utilizados 20 cães fêmeas, adultas, com idade entre 2 e 14 anos. Os animais foram separados em dois grupos, o grupo 1 formado por 12 fêmeas com diagnóstico de piometra por Escherichia coli e o grupo 2 por 8 fêmeas clinicamente sadias. Os valores na contagem de eritrócitos, hematócrito e hemoglobina nas cadelas com piometra foram significativamente inferiores aos do grupo controle. A proteína plasmática total e leucócitos totais, segmentados, bastonetes e monócitos estavam significativamente mais elevados nas cadelas com piometra que no grupo controle. Para o NBT houve aumento no grupo com piometra em relação ao grupo controle. Não houve diferença significativa entre os grupos para o teste de TBARS. Os resultados mostraram que cadelas com piometra por E. coli apresentam anemia normocítica normocrômica e leucocitose por neutrofilia com desvio a esquerda. O aumento no NBT indicou um incremento na atividade neutrofílica.

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The present work had as its objective to assess the oxidizing metabolism of neutrophils, the complete blood count (CBC) and the oxidizing profile of experimentally infected lambs with Haemonchus contortus and supplemented with selenium and vitamin E. 20 male lambs were used, of the Corriedale breed, distributed in four experimental groups with 5 animals: G1 larvae infected animals and supplemented with 0.2mg/kg living weight (PV) of selenite via intramuscular (IM); G2 larvae infected animals and supplemented with 0.2mg/kg PV of selenite IM and 2000 UI per animal of vitamin E IM; G3 larvae infected animals and supplemented with 2000 UI per animal of E IM; G4 larvae infected animals. For the CBC and the biochemical analysis blood collection on the day zero (T0) were carried out, 20 (T1), 40 (T2) and 60 (T3) through jugular venipuncture using vacutainer® tubes. The weighing and the egg determination by gram of animal feces occurred in the same experimental times. For the NBT tests heparinized blood samples were collected in the days zero, 30, 60. Smaller leukocyte values were detected in the supplemented group exclusively with selenium (G1) in relation to the control group (G4) in time 4. Concerning the lymphocytes it was observed a decrease in the G1 in relation to the supplemented only with vitamin E (G3) and G4 in time 3 (T3). For both the tests, NBT-NE and NBT-E there was a decrease in the dye reduction capacity at 60 days in relation to the other times in the groups treated with selenium (G1 and G2). The result of the oxidizing profile showed a significant elevation in the GSH-Px enzyme in the supplemented groups with selenium. Still, the correlation of Pearson revealed the existence of a negative correlation between the concentrations of GSH-Px and TBARS and between this enzyme and the OPG values. Increments were also observed for the catalase enzyme in animal which received the selenium supplementation or when this element was associated to the vitamin E. Smaller values of lipid peroxidation (TBARS) were detected in supplemented animals when these were compared to the control group. These results suggest that the reduced reserves of this antioxidant may exacerbate the generation of free radicals with an increase of the lipid peroxidation and the increase of the environment contamination by the eggs of Haemonchus contortus. Facing these results it is possible to conclude that the selenium supplementation provides a larger protection to the cell antioxidant and to the organism as a whole in lambs experimentally infected by Haemonchus contortus. / O presente trabalho teve como objetivo avaliar o metabolismo oxidativo dos neutrófilos, o hemograma e o perfil oxidativo de cordeiros experimentalmente infectados com Haemonchus contortus e suplementados com selênio e vitamina E. Foram utilizados 20 cordeiros machos, da raça Corriedale, distribuídos em quatro grupos experimentais com 5 animais: G1- animais infectados com larvas e suplementados com 0,2mg/kg de peso vivo (PV) de selenito de sódio por via intramuscular (IM); G2- animais infectados com larvas e suplementados com 0,2mg/kg PV de selenito de sódio IM e 2000 UI por animal de Vitamina E IM; G3- animais infectados com larvas e suplementados com 2000 UI por animal de Vitamina E IM; G4-animais infectados com larvas. Todos os grupos foram infectados, pela via oral, com 500 larvas L3 de Haemonchus contortus por animal a cada dois dias, pelo período de vinte dias a partir do dia zero. Para o hemograma e as análises bioquímicas foram realizadas coletas de sangue nos dias zero (T0), 20 (T1), 40 (T2) e 60 (T3) por venopunção da jugular utilizando-se tubos vacutainer®. As pesagens e a determinação dos ovos por grama de fezes dos animais ocorreram nesses mesmos tempos experimentais. Para as provas de NBT foram coletadas amostras de sangue heparinizadas nos dias zero, 30 e 60. Menores valores de leucócitos totais foram detectados no grupo suplementado exclusivamente com selênio (G1) em relação ao grupo controle (G4) no tempo 4. Em relação aos linfócitos observou-se diminuição no G1 em relação ao suplementado somente com vitamina E (G3) e G4 no tempo 3 (T3). Para ambos os testes, NBT-NE e NBT-E houve uma diminuição da capacidade de redução do corante aos 60 dias em relação aos demais tempos nos grupos tratados com selênio (G1 e G2).Os resultados do perfil oxidativo demonstraram significativa elevação da atividade da enzima GSH-Px nos grupos suplementados com selênio. Ainda, a correlação de Pearson revelou a existência de correlação negativa entre as concentrações de GSH-Px e TBARS e entre esta enzima e os valores de OPG. Incrementos também foram observados para a enzima catalase nos animais que receberam suplementação com selênio ou quando este elemento foi associado a vitamina E. Menores valores de lipoperoxidação lipídica (TBARS) foram detectados nos animais suplementados quando estes foram comparados ao grupo controle. Esses resultados sugerem que as reservas diminutas deste antioxidante podem exacerbar a geração de radicais livres com um aumento da peroxidação lipídica e o aumento da contaminação ambiental pelos ovos de Haemonchus contortus. Diante dos resultados é possível concluir que a suplementação com selênio proporciona uma maior proteção antioxidante celular e ao organismo como um todo de cordeiros experimentalmente infectados pelo Haemonchus contortus.

Les facteurs régulant l’hématopoïèse en contexte de vieillissement s’avèrent incomplètement compris. Nous avons étudié les déterminants de la variabilité des traits de la formule sanguine complète dans une cohorte de 2996 femmes apparentées et non-apparentées d’ascendance française du Québec âgées de 55 à 101 ans. Les déterminants héréditaires ont été évalués par étude d’association pan-génomique. Des facteurs acquis, incluant comorbidités et hématopoïèse clonale, ont aussi été évalués. Des analyses multivariées ont été réalisées avec des modèles linéaires mixtes généralisés. Nous avons identifié des variants dans la région de GSDMA et PSMD3-CSF3 significativement associés au décompte de neutrophiles et un polymorphisme intronique à ARHGEF3 associé au décompte plaquettaire. L’effet de certains variants diminuait avec l’âge. Avec l’âge, les décomptes de neutrophiles et monocytes augmentaient tandis que le décompte des lymphocytes décroissait. Les valeurs de neutrophiles (4,1x109/L vs 3,83x109/L, valeur-p <0,001), monocytes (0,50x109/L vs 0,45x109/L, valeur-p <0,001) et plaquettes (259x109/L vs 243x109/L, valeur-p <0,001) étaient augmentées lors de comorbidités cardiométaboliques (maladie coronarienne, hypertension, diabète, dyslipidémie). L’hématopoïèse clonale ne modifiait pas les décomptes. En conclusion, nous identifions des déterminants génétiques héréditaires contribuant à la variabilité des décomptes cellulaires sanguins dans une cohorte vieillissante. De plus, le vieillissement est associé à des niveaux accrus de neutrophiles et monocytes et une diminution des lymphocytes indiquant un biais myéloïde, lequel est majoré lors de comorbidités métaboliques. L’hématopoïèse clonale ne contribue pas à ce biais myéloïde. Ces résultats supportent le fait que des facteurs extrinsèques, possiblement via un effet inflammatoire, promeuvent le biais myéloïde relié à l’âge. / Our understanding of the factors regulating peripheral blood cell traits in the setting of aging remains incomplete. We investigated the determinants underlying blood cell trait variability in a cohort of 2996 related and unrelated women of French ancestry from Québec aged 55 to 101 years. We performed a genome-wide association study to assess for genetic variants. We also assessed the impact of acquired factors such as chronic comorbidities and clonal hematopoiesis. Multivariate analyses were subsequently performed using generalized linear mixed models. We identify variants in the region of GSDMA and PSMD3-CSF3 that meet genome-wide requirements for neutrophil counts and a variant intronic to ARHGEF3 for platelet counts. With aging, the effect of certain variants decreased. Aging was associated with increasing neutrophil and monocyte counts and decreasing lymphocyte counts. We also document that individuals with cardiometabolic comorbidities (diabetes, coronary heart disease, hypertension and dyslipidemia) exhibit significantly higher neutrophil (4.1x109/L vs 3.83x109/L, p-value <0.001), monocyte (0.50x109/L vs 0.45x109/L p-value <0.001), and platelet (259x109/L vs 243x109/L, p-value <0.001) counts. Clonal hematopoiesis did not contribute significantly to these traits. In conclusion, germline variants related to GSDMA and PSMD3-CSF3 contribute to neutrophil counts and a SNP intronic to ARHGEF3 contributes to platelet counts. Aging is associated with a myeloid shift with increased levels of neutrophils and monocytes, and reduced lymphocyte counts. This myeloid-biased skewing is further increased with cardiometabolic comorbidities. Clonal hematopoiesis does not contribute to this phenomenon. These findings support that cellextrinsic factors may contribute to the myeloid shift possibly through low-grade inflammation.