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1.
J Dairy Sci ; 103(3): 2896-2905, 2020 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-31928754

RESUMEN

The objective of this project was to develop and test a web-based virtual dairy herd to help students understand the structure and functioning of a dairy herd, and to promote active learning. At the beginning of the course, the instructor defines the profiles of herds to be assigned to students (e.g., herd size, production, diets, fertility). Each student has a unique herd and engages in decision-making for desired management practices in the herd. Modeled events are based on cow physiology and normal dairy herd management practices. Students' activities and decisions include heat detection, insemination, pregnancy diagnosis, dry-off, diet specifications, feeding groups, colostrum and milk-replacer feeding, weaning, treatment of diseases, and milk withdrawal from the tank if antibiotics are used, among others. The daily output provides information on technical indexes, economic performance, counters of incorrect decisions as feedback for students, and score. Time in class can be devoted to discussions of dairy management issues. Additional exercises based on students' own herds (e.g., calculating required space for cows, land for forage production, manure management) can also be implemented. Students' performance in the virtual dairy farm was monitored over 3 years. The average score (n = 326) was 87.8 ± 1.1 over 100 points, suggesting that self-learning with the virtual dairy farm was highly successful. At the end of each semester, students (n = 277) responded to a survey on the experience of working with the virtual dairy herd. Most students (>87%) agreed that the virtual dairy herd was more effective and motivating than traditional lectures and helped them understand dairy production better. In an unannounced test conducted at least 2 wk before the final exam, students (n = 207) were asked 14 questions on dairy cattle and 14 similar questions on other species taught in the same class through traditional lectures. A similar test on the same students (n = 142) was conducted in their fifth semester (2 years later). Results were better in dairy compared with other species questions in the first (9.6 vs. 3.7) and fifth (8.0 vs. 3.8) semesters. The virtual dairy herd is an effective tool for teaching introductory courses in dairy production. The program can be accessed at www.virtualdairyfarm.org, and a manual and videos with instructions for instructors and students are available online.


Asunto(s)
Bovinos/fisiología , Calostro/metabolismo , Industria Lechera/educación , Fertilidad , Leche/metabolismo , Interfaz Usuario-Computador , Animales , Dieta/veterinaria , Femenino , Inseminación , Lactancia , Sustitutos de la Leche/metabolismo , Embarazo
2.
Vet Res Commun ; 42(2): 121-130, 2018 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-29453596

RESUMEN

The use of natural products is a promising approach for treating visceral leishmaniosis. (-)-α-Bisabolol is a sesquiterpene that have been proved active in vivo on Leishmania infantum-infected mice without showing toxicity. A single-centre, parallel-group, randomized, exploratory study was designed to assess its efficacy in a canine leishmaniosis model involving naturally infected dogs. In this clinical trial, 12 dogs were allocated into two groups and were treated with either meglumine antimoniate (100 mg/kg) through subcutaneous route or (-)-α-bisabolol (30 mg/kg) through oral route for two treatment series of 30 days, separated by a 30-day interval. A 4-month follow-up period was established as well. Parasite loads in bone marrow, lymph node and blood were estimated through quantitative PCR. Antibody titres were determined through immunofluorescence antibody test and cytokine expression values were estimated through real-time reverse transcription-PCR. Treatment safety was assessed through the evaluation of weight, gastrointestinal alterations and hematological and biochemical parameters in blood. Analyses were performed before and after treatment, and after a 4-months follow-up period. Treatment with the sesquiterpene was effective at decreasing parasite loads and increasing gamma-interferon expression level. Dogs treated with (-)-α-bisabolol did not show any toxicity sign. These results were better than those obtained using the reference drug, meglumine antimoniate. The natural compound seemed to induce a Th1 immune response that led to parasitological and clinical improvement without showing any safety issue, suggesting a high potential for the treatment of canine and human visceral leishmaniosis.


Asunto(s)
Antiprotozoarios/uso terapéutico , Enfermedades de los Perros/tratamiento farmacológico , Leishmaniasis Visceral/veterinaria , Sesquiterpenos/uso terapéutico , Animales , Anticuerpos Antiprotozoarios/sangre , Perros , Leishmaniasis Visceral/tratamiento farmacológico , Meglumina/administración & dosificación , Meglumina/uso terapéutico , Antimoniato de Meglumina , Sesquiterpenos Monocíclicos , Compuestos Organometálicos/administración & dosificación , Compuestos Organometálicos/uso terapéutico , Carga de Parásitos , Sesquiterpenos/administración & dosificación , Resultado del Tratamiento
3.
Lupus ; 25(3): 307-9, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-26345674

RESUMEN

Renal tubular acidosis (RTA) is a rare complication of renal involvement of systemic lupus erythematosus (SLE). We describe a 24-year-old male with type IV lupus nephropathy as a presenting manifestation of SLE. He presented with improvement of renal function following induction therapy with three pulses of methylprednisolone and 500 mg biweekly pulses of cyclophosphamide. However, a week after the first pulse of cyclophosphamide, the patient presented with a significant increase in legs edema and severe hyperkalemia. Type IV RTA associated with hyporeninemic hypoaldosteronism was suspected in the presence of metabolic acidosis with a normal anion gap, severe hyperkalemia without worsening renal function, and urinary pH of 5. RTA was confirmed with a transtubular potassium concentration gradient of 2 and low levels of plasma aldosterone, renin, angiotensin II, and cortisol. Intravenous bicarbonate, high-dose furosemide, and fludrocortisone were administered with normalization of potassium levels and renal function.


Asunto(s)
Hipoaldosteronismo/etiología , Lupus Eritematoso Sistémico/complicaciones , Nefritis Lúpica/etiología , Acidosis/etiología , Antiinflamatorios/administración & dosificación , Bicarbonatos/administración & dosificación , Quimioterapia Combinada , Edema/etiología , Glucocorticoides/administración & dosificación , Humanos , Hiperpotasemia/etiología , Hipoaldosteronismo/diagnóstico , Hipoaldosteronismo/tratamiento farmacológico , Inmunosupresores/administración & dosificación , Lupus Eritematoso Sistémico/diagnóstico , Lupus Eritematoso Sistémico/tratamiento farmacológico , Nefritis Lúpica/diagnóstico , Nefritis Lúpica/tratamiento farmacológico , Masculino , Quimioterapia por Pulso , Inhibidores del Simportador de Cloruro Sódico y Cloruro Potásico/administración & dosificación , Resultado del Tratamiento , Adulto Joven
4.
Pediátr. Panamá ; 42(1): 31-40, Abril-Mayo 2013.
Artículo en Español | LILACS | ID: biblio-848906

RESUMEN

Metodología: Estudio retrospectivo, de casos y controles para comparar la morbilidad y mortalidad de los neonatos pretérminos tardíos (34 0/7 semanas a 36 6/7 semanas) en relación con los neonatos de término que fueron atendidos en el Hospital del Niño de Panamá, en el segundo semestre de 2011. Se tomaron todos los pretérminos tardíos en el período de estudio y se comparan con controles en relación 1:1. Los datos fueron obtenidos en la sección de Registros Estadísticos de Salud (REGES) del Hospital del Niño. Resultados: Hubo un total de 9118 nacimientos en este período, de los cuales 605 nacimientos fueron de pretérminos tardíos. Se excluyen 148 expedientes y se analizan 457 expedientes de cada grupo. Comparados con los neonatos de término, los pretérminos tardíos tienen mayor morbilidad (44.58% vs 8.10%): respiratoria (20.57% vs 1.75%), infecciosa (17.72% vs 2.63%), hipotermia (7.88% vs 0.44%), problemas de alimentación (6.78% vs 0.22%) y la Hiperbilirrubinemia que amerita fototerapia (22.92% vs 4.6%). Se encontró una mayor estancia intrahospitalaria (11.2 días vs 7.3 días) y costos intrahospitalarios (10 veces mayor). No se encontró asociación estadísticamente significativa en cuanto a hipoglicemia y mortalidad. Conclusión: los pretérminos tardíos tienen un riesgo importante de 11 veces más de desarrollar morbilidad y una mayor estancia intrahospitalaria generando más costos hospitalarios.


Methods: Case-control, retrospective study to compare the morbidity and mortality between late preterm infants (34 0/7 to 36 6/7 weeks of gestation) and full term infants that was attended in the Hospital del Niño of Panamá, in the period of second semester of 2011. All late preterm infants will be included and compared with 1:1 relationship to control term infants group. Data was obtained at Health Statistics Register (HSR) of Hospital del Niño. Results: During this study, born 9118 infants. 605 neonates born late preterm infants. Data of 148 late preterm infants were excluded and 457 infants were analyzed of each group. Compared with the full term infants, late preterm infants have a higher morbidity (44.58% vs 8.10%): respiratory distress (20.57% vs 1.75%), infectious problems (17.72% vs 2.63%), hypothermia (7.88% vs 0.44%), feeding problems (6.78% vs 0.22%) and jaundice requiring phototherapy (22.92% vs 4.6%). They have a higher hospitalization stay (mean, 11.2 days vs 7.3 days) and costs (10 times higher). Hypoglycemia and mortality was not statistically significant between the both groups. Conclusion: the late preterm has a significant risk of developing 11 times greater morbidity and hospital stay generating more hospital costs.

5.
Radiat Prot Dosimetry ; 119(1-4): 197-200, 2006.
Artículo en Inglés | MEDLINE | ID: mdl-16709711

RESUMEN

This work presents a study of commercial SiO2 optical fibre thermoluminescence (TL) properties as part of the efforts within the Dosimetric Application Project at the Physics Institute of the University of Mexico to develop new radiation detection materials and technologies. The SiO2 commercial optical fibre studied demonstrates useful TL properties and is an excellent candidate for use in TL dosimetry of ionising radiation. The optical fibre's glow curve was observed between 30 and 400 degrees C after exposure to 60Co gamma radiation. One very well-defined glow peak has a maximum at 230 degrees C. The TL response between 100 and 350 degrees C increases monotonically over a wide dose range, from 0.1 Gy to several kGy. It is linear in the range 0.1-3 Gy, which is important for clinical high dose or accident dosimetry. The optical fibre demonstrated high data reproducibility, low residual signal and almost no fading in our study. Moreover, the optical fibre can be re-used several times, after thermal annealing, without any detriment in the dose-response. All these TL characteristics, plus the small size of the 150 microm diameter SiO2 optical fibre, the high flexibility, easy handling and low cost compared with other TL materials, make the commercial optical fibre a very promising TL material for use in research, medicine, industry, reactors, and a variety of other applications.


Asunto(s)
Tecnología de Fibra Óptica/instrumentación , Dióxido de Silicio/química , Dióxido de Silicio/efectos de la radiación , Dosimetría Termoluminiscente/instrumentación , Dosimetría Termoluminiscente/métodos , Relación Dosis-Respuesta en la Radiación , Diseño de Equipo , Análisis de Falla de Equipo , Materiales Manufacturados , Ensayo de Materiales , Dosis de Radiación
6.
Radiat Prot Dosimetry ; 101(1-4): 561-4, 2002.
Artículo en Inglés | MEDLINE | ID: mdl-12382812

RESUMEN

In this paper we present a method for the measurement of alpha particle energy using polycarbonate materials as nuclear track detectors (NTDs). This method is based on the interaction of the radiation with the solid-state materials, using the relationship between the energy deposited in the material by the ionising particle and the track developed after an established chemical process. The determination of the geometrical parameters of the formed track, such as major axis, minor axis and overall track length, permit determination of the energy of the alpha particle. The track analysis is performed automatically using a digital image system, and the data are processed in a PC with commercial software. In this experiment 148Gd, 238U, 230Th, 239Pu and 244Cm alpha particle emitters were used. The values for alpha particle energy resolution, the linear response to energy, the confidence in the results and the automatisation of the procedure make this method a promising analysis system.


Asunto(s)
Partículas alfa , Radioisótopos de Cadmio , Plutonio , Radiometría/métodos , Termodinámica , Torio , Uranio
7.
J Nat Prod ; 55(2): 221-4, 1992 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-1624942

RESUMEN

Major components of MeOH extracts from the plant roots of Cnidosculus urens purified by cc and tlc and crystallization were lupeol acetate and the previously unreported compounds isoxochitlolone [1] and xochitloldione [2], which were identified through mass, ir, nmr, and uv spectroscopy and X-ray crystallography. In preliminary testing, isoxochitlolone has been found to be active against Escherichia coli and Staphylococcus aureus.


Asunto(s)
Antibacterianos/aislamiento & purificación , Ciclohexanonas/aislamiento & purificación , Fenoles/aislamiento & purificación , Plantas Medicinales/química , Antibacterianos/análisis , Antibacterianos/farmacología , Cromatografía en Capa Delgada , Cristalización , Ciclohexanonas/análisis , Ciclohexanonas/farmacología , Escherichia coli/efectos de los fármacos , México , Pruebas de Sensibilidad Microbiana , Fenoles/análisis , Fenoles/farmacología , Staphylococcus aureus/efectos de los fármacos , Difracción de Rayos X
8.
Electrophoresis ; 11(10): 810-2, 1990 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-2150371

RESUMEN

A method is described for detecting polymorphisms of cephalothorax and tail homogenates of 25 puerulus staged Panulirus argus in phosphoglucomutase (PGM) and esterases. Isoelectric focusing in immobilized pH gradients was used. In the pH 6.0-8.0 interval for phosphoglucomutase and in the pH 3.5-5.0 and 4.2-4.9 ranges for esterases, both enzymes appeared as polymorphic band patterns. These could be explained by one locus with 2 alleles for phosphoglucomutase and 3 loci with 2, 3 and 4 alleles for esterases. Esterases exhibit a more extensive polymorphism in immobilized pH gradients than in polyacrylamide gel electrophoresis.


Asunto(s)
Esterasas/química , Nephropidae/enzimología , Fosfoglucomutasa/química , Polimorfismo Genético , Alelos , Animales , Concentración de Iones de Hidrógeno , Focalización Isoeléctrica , Fenotipo
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