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1.
Res Vet Sci ; 166: 105099, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38091815

RESUMEN

This study aimed to assess the predictive ability of parametric models and artificial neural network method for genomic prediction of the following indicator traits of resistance to gastrointestinal nematodes in Santa Inês sheep: packed cell volume (PCV), fecal egg count (FEC), and Famacha© method (FAM). After quality control, the number of genotyped animals was 551 (PCV), 548 (FEC), and 565 (FAM), and 41,676 SNP. The average prediction accuracy (ACC) calculated by Pearson correlation between observed and predicted values and mean squared errors (MSE) were obtained using genomic best unbiased linear predictor (GBLUP), BayesA, BayesB, Bayesian least absolute shrinkage and selection operator (BLASSO), and Bayesian regularized artificial neural network (three and four hidden neurons, BRANN_3 and BRANN_4, respectively) in a 5-fold cross-validation technique. The average ACC varied from moderate to high according to the trait and models, ranging between 0.418 and 0.546 (PCV), between 0.646 and 0.793 (FEC), and between 0.414 and 0.519 (FAM). Parametric models presented nearly the same ACC and MSE for the studied traits and provided better accuracies than BRANN. The GBLUP, BayesA, BayesB and BLASSO models provided better accuracies than the BRANN_3 method, increasing by around 23% for PCV, and 18.5% for FEC. In conclusion, parametric models are suitable for genome-enabled prediction of indicator traits of resistance to gastrointestinal nematodes in sheep. Due to the small differences in accuracy found between them, the use of the GBLUP model is recommended due to its lower computational costs.


Asunto(s)
Genoma , Nematodos , Ovinos , Animales , Teorema de Bayes , Nematodos/genética , Genotipo , Fenotipo , Redes Neurales de la Computación , Modelos Genéticos , Polimorfismo de Nucleótido Simple
6.
J Helminthol ; 96: e77, 2022 Oct 21.
Artículo en Inglés | MEDLINE | ID: mdl-36268741

RESUMEN

In order to identify types of forage that inhibit pasture contamination, an evaluation was performed of the effect of the forage legumes Trifolium repens (white clover), Trifolium pratense (red clover) and Lotus corniculatus (bird's-foot-trefoil) on the survival and migration of infective larvae (L3) of gastrointestinal nematodes (GIN) of sheep. An experimental area of 441 m2 was divided into four blocks, subdivided into areas of 1.20 × 1.20 in which the three forage legumes were separately overseeded. After growth of the forage in each subdivision, experimental units were established that were later artificially contaminated with sheep faeces containing GIN eggs. Between October and December 2018, pasture, faecal and soil samples were collected on four occasions during weeks 1, 2, 4 and 8 after the deposition of faeces. In week 6, the forage legumes in all the experimental units were mown to simulate grazing. The number of L3 was quantified to determine their survival in the pasture, faeces and soil. In addition, the horizontal migration of L3 was measured at two distances from the faecal pellets (10 and 30 cm), as well as their vertical migration at two heights of the plant stems, that is, lower half and upper half. Larvae vertical migration was affected by the forage species (P < 0.001), in that bird's-foot-trefoil contained fewer larvae in the upper stratum. Bird's-foot-trefoil restricted the migration of L3 to the upper stratum of the plant, which could potentially decrease the risk of infection by intestinal nematodes in grazing sheep.


Asunto(s)
Fabaceae , Helmintos , Nematodos , Enfermedades de las Ovejas , Ovinos , Animales , Heces , Larva , Verduras , Suelo
7.
Sci Rep ; 11(1): 4385, 2021 02 23.
Artículo en Inglés | MEDLINE | ID: mdl-33623051

RESUMEN

Easy, quantitative measures of biomolecular heterogeneity and high-stratified phenotyping are needed to identify and characterise complex disease processes at the single-cell level, as well as to predict cell fate. Here, we demonstrate how Raman spectroscopy can be used in the difficult-to-assess case of clonal, bone-derived mesenchymal stromal cells (MSCs) to identify MSC lines and group these according to biological function (e.g., differentiation capacity). Biomolecular stratification is achieved using high-precision measures obtained from representative statistical sampling that also enable quantified heterogeneity assessment. Application to primary MSCs and human dermal fibroblasts shows use of these measures as a label-free assay to classify cell sub-types within complex heterogeneous cell populations, thus demonstrating the potential for therapeutic translation, and broad application to the phenotypic characterisation of other cells.


Asunto(s)
Células Madre Mesenquimatosas/citología , Análisis de la Célula Individual/métodos , Espectrometría Raman/métodos , Diferenciación Celular , Línea Celular , Células Cultivadas , Fibroblastos/citología , Fibroblastos/metabolismo , Humanos , Células Madre Mesenquimatosas/metabolismo , Fenotipo
8.
Appl Clin Inform ; 5(2): 349-67, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25024754

RESUMEN

BACKGROUND: The ability to manage and leverage family history information in the electronic health record (EHR) is crucial to delivering high-quality clinical care. OBJECTIVES: We aimed to evaluate existing standards in representing relative information, examine this information documented in EHRs, and develop a natural language processing (NLP) application to extract relative information from free-text clinical documents. METHODS: We reviewed a random sample of 100 admission notes and 100 discharge summaries of 198 patients, and also reviewed the structured entries for these patients in an EHR system's family history module. We investigated the two standards used by Stage 2 of Meaningful Use (SNOMED CT and HL7 Family History Standard) and identified coverage gaps of each standard in coding relative information. Finally, we evaluated the performance of the MTERMS NLP system in identifying relative information from free-text documents. RESULTS: The structure and content of SNOMED CT and HL7 for representing relative information are different in several ways. Both terminologies have high coverage to represent local relative concepts built in an ambulatory EHR system, but gaps in key concept coverage were detected; coverage rates for relative information in free-text clinical documents were 95.2% and 98.6%, respectively. Compared to structured entries, richer family history information was only available in free-text documents. Using a comprehensive lexicon that included concepts and terms of relative information from different sources, we expanded the MTERMS NLP system to extract and encode relative information in clinical documents and achieved a corresponding precision of 100% and recall of 97.4%. CONCLUSIONS: Comprehensive assessment and user guidance are critical to adopting standards into EHR systems in a meaningful way. A significant portion of patients' family history information is only documented in free-text clinical documents and NLP can be used to extract this information.


Asunto(s)
Registros Electrónicos de Salud , Relaciones Familiares , Informática Médica/métodos , Adulto , Femenino , Humanos , Masculino , Procesamiento de Lenguaje Natural , Terminología como Asunto
9.
Appl Clin Inform ; 4(2): 304-16, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23874366

RESUMEN

BACKGROUND: Site-specific content configuration of vendor-based Electronic Health Records (EHRs) is a vital step in the development of standardized and interoperable content that can be used for clinical decision-support, reporting, care coordination, and information exchange. The multi-site, multi-stakeholder Acute Care Documentation (ACD) project at Partners Healthcare Systems (PHS) aimed to develop highly structured clinical content with adequate breadth and depth to meet the needs of all types of acute care clinicians at two academic medical centers. The Knowledge Management (KM) team at PHS led the informatics and knowledge management effort for the project. OBJECTIVES: We aimed to evaluate the role, governance, and project management processes and resources for the KM team's effort as part of the standardized clinical content creation. METHODS: We employed the Center for Disease Control's six step Program Evaluation Framework to guide our evaluation steps. We administered a forty-four question, open-ended, semi-structured voluntary survey to gather focused, credible evidence from members of the KM team. Qualitative open-coding was performed to identify themes for lessons learned and concluding recommendations. RESULTS: Six surveys were completed. Qualitative data analysis informed five lessons learned and thirty specific recommendations associated with the lessons learned. The five lessons learned are: 1) Assess and meet knowledge needs and set expectations at the start of the project; 2) Define an accountable decision-making process; 3) Increase team meeting moderation skills; 4) Ensure adequate resources and competency training with online asynchronous collaboration tools; 5) Develop focused, goal-oriented teams and supportive, consultative service based teams. CONCLUSIONS: Knowledge management requirements for the development of standardized clinical content within a vendor-based EHR among multi-stakeholder teams and sites include: 1) assessing and meeting informatics knowledge needs, 2) setting expectations and standardizing the process for decision-making, and 3) ensuring the availability of adequate resources and competency training.


Asunto(s)
Conducta Cooperativa , Registros Electrónicos de Salud , Documentación , Registros Electrónicos de Salud/normas , Estudios de Evaluación como Asunto , Humanos , Atención al Paciente , Estándares de Referencia
10.
Food Chem Toxicol ; 59: 104-10, 2013 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-23747712

RESUMEN

Fluoride is considered important for health because of its beneficial effect on the prevention of dental caries and on bone development in the child population. However, excessive intake has negative effects. The main pathway for exposure is oral, through consumption of drinking water, and some food products. Therefore its bioaccessibility (quantity of the element solubilized during the digestive process) is a parameter to be considered when estimating the risk/benefit associated with this element. The aim of the present study was to evaluate the influence of the digestion phase, gastrointestinal digestion factors (pH, pepsin and bile salt concentrations) and the presence of cations on the bioaccessibility of fluoride from seafood products. The results show that the solubilization of fluoride takes place entirely during the gastric phase. Its bioaccessibility is strongly influenced by conditions that favor the formation of insoluble complexes of fluoride with other elements present in the matrix. The factors that are most influential in reducing its bioaccessibility are the increase in pH in the gastric phase, the presence of cations, especially in the intestinal phase, and a low concentration of bile salts.


Asunto(s)
Digestión , Fluoruros/metabolismo , Mucosa Gástrica/metabolismo , Mucosa Intestinal/metabolismo , Modelos Biológicos , Alimentos Marinos/análisis , Mariscos/análisis , Animales , Ácidos y Sales Biliares/metabolismo , Calcio de la Dieta/efectos adversos , Calcio de la Dieta/metabolismo , Peces , Fluoruros/análisis , Fluoruros/química , Humanos , Concentración de Iones de Hidrógeno , Hierro de la Dieta/efectos adversos , Hierro de la Dieta/metabolismo , Metales Ligeros/efectos adversos , Metales Ligeros/metabolismo , Valor Nutritivo , Concentración Osmolar , Penaeidae/química , Pepsina A/metabolismo , Solubilidad
11.
Food Chem Toxicol ; 55: 156-63, 2013 May.
Artículo en Inglés | MEDLINE | ID: mdl-23291323

RESUMEN

Water and food are the main sources of fluoride exposure and therefore it is necessary to study intestinal absorption in order to make a correct evaluation of the risk/benefit associated with exposure to fluoride. The present study characterizes intestinal transport of fluoride, using the Caco-2 cell line as a model of the intestinal epithelium, and evaluates the coefficients of apparent permeability and intracellular accumulation in various conditions (pH, temperature, opening of cell junctions, presence of anions). The results indicate that fluoride is an element with moderate absorption (<70%) in both directions (absorptive and secretory). Both in absorption (apical-basolateral) and in secretion (basolateral-apical) there is transport by the paracellular pathway, which may be considered predominant. Absorption and secretion of fluoride increase at acid pH levels, possibly because of its non-ionized state at these pHs and/or because of participation of a F(-)/H(+) cotransporter or a F(-)/OH(-) antiporter. The results also suggest transcellular participation of mechanisms involved in transport of Cl(-) and of an active transport in the secretory direction. The present study extend the knowledge on the cellular transport of fluoride and provide the basis for future studies aimed at identifying potential transporters involved in human fluoride absorption.


Asunto(s)
Fluoruros/metabolismo , Mucosa Intestinal/metabolismo , Células CACO-2 , Humanos , Técnicas In Vitro
12.
Toxicol Lett ; 210(3): 311-7, 2012 May 05.
Artículo en Inglés | MEDLINE | ID: mdl-22387159

RESUMEN

The main routes of fluoride (F) exposure are drinking water and certain foods; consequently, intestinal absorption is an important stage in the study of F exposure. In the present study, different cell models [Caco-2, HT29-MTX and various proportions of Caco-2/HT29-MTX)] were used to evaluate intestinal transport of F. The influence of cell type, pH, mucus layer, bile salts and food matrices on the apparent permeability coefficient (P(app)) was evaluated. The results show that a higher proportion of HT29-MTX in the monolayer produces an increase in F permeability, although the mucus layer secreted by HT29-MTX decreases F transport. The results also show that taurocholic acid, a component of bile salts, and acid pH increase F permeability, whereas the presence of a food matrix (rice) decreases intestinal transport of F. In all cases, alterations in F permeability were closely related with modulation of cell junctions.


Asunto(s)
Fluoruros/farmacocinética , Absorción Intestinal , Células CACO-2 , Impedancia Eléctrica , Humanos , Concentración de Iones de Hidrógeno , Modelos Biológicos , Permeabilidad , Ácido Taurocólico/farmacología
13.
Eur J Dent Educ ; 15(4): 199-204, 2011 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-21985202

RESUMEN

During paediatric dental treatment, non-collaboration and fearful reactions are frequently observed in the child client. The dentistry student must be prepared to cope with these reactions, particularly considering the importance of the relationship between dentists and patients in the promotion of oral health. The present study aimed to assess undergraduate dentistry students' perceptions of their ability to cope with non-collaboration situations in paediatric dentistry. A Likert-style questionnaire was used to analyse students' self-confidence levels, and proposed solutions to 10 problem situations the students would be likely to encounter were recorded. The questionnaire was administered to two undergraduate dentistry student groups from two different Brazilian Public Faculties, comprising 122 respondents. The self-confidence analysis indicated that it varied according to the extent of the child's reaction and the invasiveness of the procedure. Responses to the open-ended questions were categorised by solution proposed, and the analysis indicated that the most frequent responses were categorised as follows: tranquilising, explanation and restriction. Significant differences were found in tranquilising (with higher values for Faculty 2 than 1, and higher values for female students than male students at Faculty 2) and restriction (with higher values for female students compared with male student at both Faculties). The results and discussion focused on the aspects of training dentistry students' social and behavioural management skills.


Asunto(s)
Adaptación Psicológica , Relaciones Dentista-Paciente , Odontología Pediátrica/educación , Autoimagen , Estudiantes de Odontología/psicología , Brasil , Distribución de Chi-Cuadrado , Niño , Preescolar , Femenino , Humanos , Masculino , Encuestas y Cuestionarios
14.
Vet Parasitol ; 181(2-4): 229-38, 2011 Sep 27.
Artículo en Inglés | MEDLINE | ID: mdl-21726941

RESUMEN

This experiment aimed to evaluate the effect of periparturient metabolizable protein (MP) nutrition on resistance to Haemonchus contortus in single rearing Ile de France and Santa Ines ewes. The restriction-fed iso-energetic diet was calculated to provide either 0.8 (low MP diet) or 1.3 (high MP diet) times MP, from three weeks before parturition until eight weeks into lactation. The ewes were experimentally infected with 1000 H. contortus infective larvae (L3) three times a week (Mondays, Wednesdays and Fridays), starting five weeks before the predicted date for parturition until a total of 15,000 L3 had been administered. While both breeds showed elevated fecal egg counts (FEC), these values were significantly lower for Santa Ines ewes than Ile de France ewes, but were independent of level of MP feeding. The latter also did not affect lamb weight gain and ewe body weight variation in each breed. Packed cell volume and total plasma protein for Santa Ines in all periods were significantly higher than those for Ile de France ewes (P<0.01) but were not affected by nutrition. In contrast, levels of serum IgG and IgA antibodies against somatic H. contortus infective larvae and adult antigens were similar between breeds but higher in animals that received high MP diets (P<0.05). The reduced body score of ewes at the beginning of the experiment probably influenced their high susceptibility to incoming larvae. Since, unexpectedly, MP scarcity was not achieved in this experiment, our data support the view that Santa Ines ewes are more resistant to H. contortus than Ile de France ewes.


Asunto(s)
Proteínas en la Dieta/farmacología , Suplementos Dietéticos , Hemoncosis/veterinaria , Lactancia/fisiología , Alimentación Animal/análisis , Animales , Peso Corporal/efectos de los fármacos , Heces/parasitología , Femenino , Hemoncosis/sangre , Hemoncosis/tratamiento farmacológico , Haemonchus , Hematócrito , Inmunoglobulina A , Inmunoglobulina G , Embarazo , Ovinos
15.
Toxicol Lett ; 203(3): 237-44, 2011 Jun 24.
Artículo en Inglés | MEDLINE | ID: mdl-21439358

RESUMEN

The aim of the present study is to determine the effect of inorganic arsenic (As) and its metabolites on the viability of the neural progenitor cell (NPC) line C17.2, in order to evaluate cellular mechanisms involved in As developmental neurotoxicity. Moreover, we analyzed the effects of the coexposure to As and fluoride (F), a situation to which some populations are commonly exposed. Our results show that NPCs are not susceptible to pentavalent As species [arsenate, monomethylarsonic acid, and dimethylarsinic acid] and F alone. However, the trivalent metabolites of arsenate [arsenite, monomethylarsonous acid, and dimethylarsinous acid] are toxic at concentrations below 1 mg/l, and this susceptibility increases when there is coexposure with F (≥ 5 mg/l). Arsenite triggers apoptosis after 24 h of exposure, whereas monomethylarsonous acid produces necrosis at very short times (2 h). Arsenite leads to an increase in intracellular Ca levels and generation of reactive oxygen species, which may cause a decrease in mitochondrial transmembrane potential, release of cytochrome c, and consequent activation of caspases. A slight activation of calpain also takes place, which might favor activation of the mitochondrial pathway or might activate other pathways. The treatment with some antioxidants such as quercetin and α-tocopherol shows only a partial reduction of the cytotoxicity.


Asunto(s)
Apoptosis/efectos de los fármacos , Arsénico/toxicidad , Fluoruros/toxicidad , Células-Madre Neurales/efectos de los fármacos , Animales , Anexina A5/análisis , Antioxidantes/farmacología , Calcio/metabolismo , Calpaína/metabolismo , Caspasas/metabolismo , Línea Celular , Supervivencia Celular/efectos de los fármacos , Potencial de la Membrana Mitocondrial/efectos de los fármacos , Ratones , Células-Madre Neurales/citología , Células-Madre Neurales/fisiología , Especies Reactivas de Oxígeno/metabolismo
16.
Vet Parasitol ; 171(1-2): 68-73, 2010 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-20409640

RESUMEN

This study aimed to evaluate the expression of a subset of cytokine genes in response to Haemonchus placei infections in Nelore cattle presenting different degrees of resistance to natural infections. One hundred weaned bulls, initially 11-12 months old, were evaluated and kept on the same pasture. Faecal and blood samples were collected for parasitological and immunological assays. The seven most resistant and the eight most susceptible animals were selected based on nematode faecal egg counts (FEC) and worm burden. Serum was collected to measure antibody titres, and abomasum and abomasal lymph node tissue samples were collected to analyse the expression of a subset of cytokine genes (IL-2, IL-4, IL-8, IL-12p35, IL-13, TNF-alpha, IFN-gamma, MCP-1, MCP-2, MUC-1) using real-time RT-PCR. Mast cells, eosinophils and globule leukocytes in the abomasal mucosa were enumerated, and IgA levels in the mucus were assessed. Gene expression analysis in the abomasal tissue indicated that IL-4 and IL-13 (TH2 cytokines) were up-regulated in the resistant group, whereas TNF-alpha (TH1/TH2 cytokine) was up-regulated in the susceptible group. In abomasal lymph nodes, IL-4 and IFN-gamma were up-regulated in the resistant and susceptible groups, respectively. In the resistant group, serum IgG1 levels were higher against antigens of H. placei infective larvae on days 14, 42, 70 and 84 and against antigens of H. placei adults on day 84 (P<0.05). The resistant group had higher mast cell counts in the abomasal mucosa than the susceptible group (P<0.05). These results indicate a protective TH2-mediated immune response against H. placei in the resistant group and a less protective TH1 response in the susceptible group.


Asunto(s)
Enfermedades de los Bovinos/parasitología , Citocinas/inmunología , Enfermedades Gastrointestinales/veterinaria , Regulación de la Expresión Génica/inmunología , Hemoncosis/veterinaria , Haemonchus/inmunología , Animales , Bovinos , Enfermedades de los Bovinos/inmunología , Citocinas/sangre , Citocinas/genética , Heces/parasitología , Enfermedades Gastrointestinales/inmunología , Enfermedades Gastrointestinales/parasitología , Perfilación de la Expresión Génica/veterinaria , Hemoncosis/inmunología , Hemoncosis/parasitología , Haemonchus/genética , Histocitoquímica/veterinaria , Inmunoglobulinas/sangre , Ganglios Linfáticos/inmunología , Ganglios Linfáticos/parasitología , Masculino , Recuento de Huevos de Parásitos/veterinaria , ARN/química , ARN/genética , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa/veterinaria
17.
Int Endod J ; 42(11): 992-6, 2009 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-19825035

RESUMEN

AIM: To evaluate in vitro the effect of calcium hydroxide [Ca(OH)(2)] and Er:YAG laser on bacterial endotoxin [also known as lipopolysaccharide (LPS)] as determined by nitric oxide (NO) detection in J774 murine macrophage cell line culture. METHODOLOGY: Samples of LPS solution (50 microg mL(-1)), Ca(OH)(2) suspension (25 mg mL(-1)) and LPS suspension with Ca(OH)(2) were prepared. The studied groups were: I - LPS (control); II - LPS + Ca(OH)(2); III - LPS + Er:YAG laser (15 Hz 140 mJ); IV - LPS + Er:YAG laser (15 Hz 200 mJ); V - LPS + Er:YAG laser (15 Hz 250 mJ), VI - Pyrogen-free water; VII - Ca(OH)(2). Murine macrophage J774 cells were plated and 10 microL of the samples were added to each well. The supernatants were collected for NO detection by the Griess reaction. Data were analysed statistically by one-way anova and Tukey's test at 5% significance level. RESULTS: The mean and SE (in micromol L(-1)) values of NO release were: I - 10.48 +/- 0.58, II - 6.41 +/- 0.90, III - 10.2 +/- 0.60, IV - 8.35 +/- 0.40, V - 10.40 +/- 0.53, VI - 3.75 +/- 0.70, VII - 6.44 +/- 0.60; and the values for the same experiment repeated after 1 week were: I - 21.20 +/- 1.50, II - 9.10 +/- 0.60, III - 19.50 +/- 1.00, IV - 18.50 +/- 0.60, V - 21.30 +/- 0.90, VI - 2.00+/- 0.20, VII - 6.80 +/- 1.70. There was no significant difference (P > 0.05) between the control and the laser-treated groups (III, IV and V), or comparing groups II, VI and VII to each other (P > 0.05). Group I had significantly higher NO release than group II (P < 0.05). Groups II and VI had similar NO release (P > 0.05). CONCLUSIONS: Calcium hydroxide inactivated the bacterial endotoxin (LPS) whereas none of the Er:YAG laser parameter settings had the same effectiveness.


Asunto(s)
Hidróxido de Calcio/farmacología , Láseres de Estado Sólido , Lipopolisacáridos/antagonistas & inhibidores , Macrófagos/metabolismo , Óxido Nítrico/biosíntesis , Irrigantes del Conducto Radicular/farmacología , Animales , Línea Celular , Escherichia coli/química , Macrófagos/efectos de los fármacos , Ratones , Óxido Nítrico/análisis
18.
Vet Parasitol ; 165(3-4): 273-80, 2009 Nov 12.
Artículo en Inglés | MEDLINE | ID: mdl-19656629

RESUMEN

This trial was carried out in Piracicaba, São Paulo State, Brazil, to comparatively evaluate the degree of resistance to naturally acquired gastrointestinal nematode infections in sheep of the following genetic groups: purebred Santa Ines (SI), SI crossbred with Dorper (DO x SI), Ile de France (IF x SI), Suffolk (SU x SI), and Texel (TE x SI). Fifteen ewes from each group were raised indoors until 12 months of age. At this age, they were moved to pasture that was naturally contaminated by nematode infective larvae and were evaluated from December to May, 2007. Rainfall ranged from 267 mm in January to 37 mm in April. Maximum and minimum mean temperatures ranged from 32.5 degrees C to 19.0 degrees C in March and from 25.9 degrees C to 12.8 degrees C in May. There was an increase in the mean number of eggs per gram of feces (EPG) after animals were placed on pasture with significant difference between the SI (80 EPG) and IF x SI (347 EPG) groups in January; and the DO x SI (386 EPG) and TE x SI (258 EPG) groups in May. The highest mean fecal egg count (FEC), 2073 EPG, was recorded for the TE x SI group in February. All groups showed a progressive reduction in body weight throughout the experiment of 12.0% (TE x SI) to 15.9% (SU x SI). In general, the animals with the highest FEC presented the lowest packed cell volumes (PCV); the highest correlation coefficient between FEC x PCV occurred in the SU x SI sheep in January (r=-0.70; P<0.01). Similarly, there was an inverse relationship between FEC and blood eosinophil values, with the highest correlation coefficient in the TE x SI sheep in February (r=-0.64; P<0.05). Immunoglobulin G (IgG) levels against Haemonchus contortus antigens increased in all groups as a result of the exposure to parasites and remained relatively constant until the end of the study, with the exceptions of SU x SI and TE x SI, which showed a rise in IgG levels during the last sampling that coincided with a reduction in mean FEC. In conclusion, crossbreeding Santa Ines sheep with any of the breeds evaluated can result in a production increase and the maintenance of a satisfactory degree of infection resistance, especially against H. contortus and Trichostrongylus colubriformis, the major nematodes detected in this flock.


Asunto(s)
Cruzamiento , Enfermedades Gastrointestinales/genética , Enfermedades Gastrointestinales/parasitología , Inmunidad Innata/genética , Nematodos/fisiología , Infecciones por Nematodos/veterinaria , Enfermedades de las Ovejas/genética , Animales , Peso Corporal , Heces/parasitología , Femenino , Hematócrito , Larva , Masculino , Infecciones por Nematodos/genética , Recuento de Huevos de Parásitos , Ovinos
19.
Vet Parasitol ; 155(1-2): 95-103, 2008 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-18513872

RESUMEN

Cellular and humoral immune response, as well as cytokine gene expression, was assessed in Nelore cattle with different degrees of resistance to Cooperia punctata natural infection. One hundred cattle (male, weaned, 11-12 months old), kept together on pasture, were evaluated. Faecal and blood samples were collected for parasitological and immunological assays. Based on nematode faecal egg counts (FEC) and worm burden, the seven most resistant and the eight most susceptible animals were selected. Tissue samples of the small intestine were collected for histological quantification of inflammatory cells and analysis of cytokine gene expression (IL-2, IL-4, IL-8, IL-12p35, IL-13, TNF-alpha, IFN-gamma, MCP-1, MCP-2, and MUC-1) using real-time RT-PCR. Mucus samples were also collected for IgA levels determination. Serum IgG1 mean levels against C. punctata antigens were higher in the resistant group, but significant differences between groups were only observed 14 days after the beginning of the experiment against infective larvae (L3) and 14 and 84 days against adult antigens. The resistant group also presented higher IgA levels against C. punctata (L3 and adult) antigens with significant difference 14 days after the beginning of the trial (P<0.05). In the small-intestine mucosa, levels of IgA anti-L3 and anti-adult C. punctata were higher in the resistant group, compared with the susceptible group (P<0.05). Gene expression of both T(H)2 cytokines (IL-4 and IL-13) in the resistant group and T(H)1 cytokines (IL-2, IL-12p35, IFN-gamma and MCP-1) in the susceptible group was up-regulated. Such results suggested that immune response to C. punctata was probably mediated by T(H)2 cytokines in the resistant group and by T(H)1 cytokines in the susceptible group.


Asunto(s)
Enfermedades de los Bovinos/genética , Citocinas/metabolismo , Perfilación de la Expresión Génica/veterinaria , Predisposición Genética a la Enfermedad , Infecciones por Nematodos/veterinaria , Animales , Bovinos , Enfermedades de los Bovinos/inmunología , Enfermedades de los Bovinos/parasitología , Citocinas/genética , Regulación de la Expresión Génica/fisiología , Inmunoglobulina A , Infecciones por Nematodos/inmunología , Infecciones por Nematodos/parasitología
20.
J Helminthol ; 81(4): 387-92, 2007 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-18005462

RESUMEN

The efficacy of the nematode-trapping fungus Duddingtonia flagrans against infections by trichostrongyle nematodes in sheep was assessed throughout 6 months. Twenty Ile de France lambs were divided into two groups (control and treated groups), which were kept in separate pastures. Animals of the treated group were fed with D. flagrans twice a week (Tuesdays and Fridays). Pellets were prepared with the fungus mycelia in liquid culture medium and contained approximately 20% fungus. They were mixed with the animals' diet at a concentration of 1 g pellet per 10 kg live weight. Faecal egg counts (FEC), packed cell volume (PCV), total serum protein and the animals' body weight were determined fortnightly from 7 October 2005 to 24 March 2006. Comparison of such parameters between groups showed no significant differences (P > 0.05), except on 10 February 2006, when the control group presented a higher mean FEC than the treated group (P < 0.05). Feeding sheep with pellets containing D. flagrans had no benefit to the prophylaxis of nematode infections under the experimental conditions used in the present study.


Asunto(s)
Ascomicetos/enzimología , Hemoncosis/parasitología , Haemonchus/microbiología , Enfermedades de las Ovejas/parasitología , Esporas Fúngicas/metabolismo , Tricostrongiliasis/parasitología , Trichostrongylus/microbiología , Análisis de Varianza , Alimentación Animal , Animales , Estudios de Casos y Controles , Heces/parasitología , Hemoncosis/prevención & control , Hemoncosis/veterinaria , Haemonchus/crecimiento & desarrollo , Recuento de Huevos de Parásitos/veterinaria , Control Biológico de Vectores , Ovinos , Enfermedades de las Ovejas/prevención & control , Oveja Doméstica , Tricostrongiliasis/prevención & control , Tricostrongiliasis/veterinaria , Trichostrongylus/crecimiento & desarrollo
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