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1.
J Vet Med Educ ; 48(2): 181-195, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-31873057

RESUMEN

Blended learning has received much interest in higher education as a way to increase learning efficiency and effectiveness. By combining face-to-face teaching with technology-enhanced learning through online resources, students can manage their own learning. Blended methods are of particular interest in professional degree programs such as veterinary medicine in which students need the flexibility to undertake intra- and extramural activities to develop the range of competencies required to achieve professional qualification. Yet how veterinary students engage with blended learning activities and whether they perceive the approach as beneficial is unclear. We evaluated blended learning through review of student feedback on a 4-week clinical module in a veterinary degree program. The module combined face-to-face sessions with online resources. Feedback was collected by means of a structured online questionnaire at the end of the module and log data collected as part of a routine teaching audit. The features of blended learning that support and detract from students' learning experience were explored using quantitative and qualitative methods. Students perceived a benefit from aspects of face-to-face teaching and technology-enhanced learning resources. Face-to-face teaching was appreciated for practical activities, whereas online resources were considered effective for facilitating module organization and allowing flexible access to learning materials. The blended approach was particularly appreciated for clinical skills in which students valued a combination of visual resources and practical activities. Although we identified several limitations with online resources that need to be addressed when constructing blended courses, blended learning shows potential to enhance student-led learning in clinical courses.


Asunto(s)
Educación en Veterinaria , Animales , Curriculum , Humanos , Aprendizaje , Percepción , Estudiantes
2.
Nurse Educ Pract ; 17: 167-73, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-26776315

RESUMEN

In work integrated learning, students may report difficulties applying theory learned at university to clinical practice. One contributing factor may be students' inability to engage in meaningful reflection and self-correcting behaviours. This paper reports the evaluation of a tool, process and resources developed to assist students to reflect on feedback and engage in self-assessment. Students were assisted to develop self-assessment skills by reflecting on, and engaging with feedback from previous workplace experiences to develop goals, learning outcomes and strategies to improve performance with mostly positive results. A secondary aim was to identify common learning strategies or barriers that impacted on student outcomes. Four themes emerged from the qualitative data: 1) preparing for clinical learning, 2) relationships and engagement levels, 3) shared awareness and, 4) developing clinical practice. Overall students felt the tool assisted them to narrow their attention on what needed to be improved. While supervisors believed the tool helped them to focus on specific needs of each student. Common barriers to clinical practice improvement related to a lack of opportunity in some settings, and lack of staff willingness to support students to achieve identified goals. Students and supervisors found the use of the tools beneficial and assisted students to demonstrate a greater understanding of how to apply feedback received to support their learning in the clinical environment.


Asunto(s)
Retroalimentación , Preceptoría , Estudiantes del Área de la Salud , Estudiantes de Enfermería , Encuestas y Cuestionarios , Humanos , Aprendizaje , Investigación Cualitativa , Autoevaluación (Psicología) , Lugar de Trabajo/psicología
3.
Curr Microbiol ; 69(5): 681-9, 2014 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-24972665

RESUMEN

Artificial climbing walls represent a unique indoor environment in which humans interact closely with a variety of surface types. Climbing wall holds may mediate transmission of organisms between individuals, and yet there are no studies that identify microorganisms present on these surfaces. In the current study, the microorganisms found on climbing wall holds were characterized by analysis of amplified SSU rRNA gene sequences. In contrast to many other studies of built environments, the majority of microorganisms on holds were most closely related to microbes annotated as being recovered from environmental sources, such as soil, with human skin also representing an important source. Regional patterns were evident as rRNA gene sequences from the marine cyanobacterium Prochlorococcus were abundant in gyms found within 16 km of the ocean. Enterobacteriaceae were present on 100 % of holds surveyed, and the members detected are commonly associated with fecal matter.


Asunto(s)
Bacterias/clasificación , Bacterias/genética , Biota , Microbiología Ambiental , Análisis por Conglomerados , ADN Ribosómico/química , ADN Ribosómico/genética , Humanos , Datos de Secuencia Molecular , Filogenia , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN , Deportes
4.
Int J Sports Med ; 34(3): 191-5, 2013 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-22972246

RESUMEN

We examined the possible negative interaction of the combined use of the NSAID indomethacin (IND) and exercise in mice. Mice were assigned to one of 4 groups: Exercise 2.5 mg/kg IND (Ex-2.5), Sedentary 2.5 mg/kg IND (Sed-2.5), Exercise 5.0 mg/kg IND (Ex-5.0) and Sedentary 5.0 mg/kg IND (Sed-5.0). Mice were given IND (gavage) 1 h prior to exercise (treadmill run at 30 m/min, 8% grade for 90 min) or rest for 14 consecutive days. Run times, body weight and mortality were recorded daily. Sed-5.0 was highly toxic and caused 70% mortality compared to Sed-2.5, which was well tolerated (0% mortality) (P<0.05). While the addition of exercise had no greater effect on mortality in Ex-5.0, it increased it in the 2.5 group (52% vs. 0%; P<0.05). Run time was reduced from baseline beginning on day 2 (Ex-5.0), or day 3 (Ex-2.5) (P<0.05). Body weight (recorded in the 2.5 mg/kg groups only) was decreased from baseline in Ex-2.5 and Sed-2.5 (P<0.05), but this effect occurred earlier and was of greater magnitude in Ex-2.5. Exercise combined with IND use can lead to serious side effects in mice. Future research is needed to test the hypothesis that this effect is due to increased GI permeability and whether humans are also at risk.


Asunto(s)
Antiinflamatorios no Esteroideos/toxicidad , Indometacina/toxicidad , Actividad Motora , Análisis de Varianza , Animales , Antiinflamatorios no Esteroideos/administración & dosificación , Peso Corporal/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Esquema de Medicación , Prueba de Esfuerzo , Indometacina/administración & dosificación , Masculino , Ratones , Ratones Endogámicos ICR , Resistencia Física/efectos de los fármacos , Distribución Aleatoria , Análisis de Supervivencia
5.
Cytokine ; 55(2): 274-9, 2011 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-21600785

RESUMEN

Many observational epidemiologic studies suggest an association between exercise and breast cancer risk. However, the lack of controlled experimental studies that examine this relationship and the mechanisms involved weaken the basis for inferring a causal relationship. Inflammation plays a role in breast cancer progression and exercise has been reported to reduce inflammation; however, the anti-inflammatory effects of exercise in breast cancer have yet to be established. We examined the relationship between exercise training and systemic inflammation in relation to breast cancer progression in C3(1)SV40Tag mice. Female C3(1)SV40Tag mice were assigned to either exercise (Ex) or sedentary (Sed) treatment (n=12-14/group). Beginning at 4 wks of age mice (Ex) were run on a treadmill for 60 min/d (20 m/min and 5% grade), 6 d/wk for a period of 20 wks. Mice were examined weekly for palpable tumors, and tumor number and volume were recorded. At 24 wks of age mice were sacrificed and a more direct measure of tumor number and volume, and spleen weight was recorded. Plasma was analyzed for MCP-1 and IL-6 concentration using ELISA. Ex reduced palpable tumor number at sacrifice (24 wks) by approximately 70% (P<0.05). Tumor volume was also reduced in Ex at 21-23 wks (P<0.05). This reduction in tumor progression by Ex was associated with a reduction in plasma concentration of MCP-1 and IL-6, and spleen weight (P<0.05). These data provide strong support for a beneficial effect of exercise training on tumor progression in the C3(1)SV40Tag mouse model of breast cancer that may be partly mediated by its anti-inflammatory potential.


Asunto(s)
Neoplasias de la Mama/patología , Neoplasias de la Mama/terapia , Progresión de la Enfermedad , Inflamación/patología , Inflamación/terapia , Condicionamiento Físico Animal , Animales , Biomarcadores de Tumor/metabolismo , Peso Corporal , Ingestión de Alimentos , Femenino , Masculino , Ratones , Ratones Transgénicos , Distribución Aleatoria , Bazo/anatomía & histología
6.
Brain Behav Immun ; 22(8): 1152-5, 2008 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-18616997

RESUMEN

Exercise stress is associated with an increased risk for upper respiratory tract infection (URTI) while moderate exercise has been associated with a decreased risk. We have shown that exercise stress can increase susceptibility (morbidity, symptom severity and mortality) to HSV-1 respiratory infection, but there is little evidence on the effects of stressful exercise on susceptibility to the principal etiological agents of human respiratory infections, including influenza viruses. This study examined the effects of stressful exercise on susceptibility to influenza virus (A/Puerto Rico/8/34 (H1N1)). Mice were assigned to one of two groups: exercise (Ex) or control (Con). Exercise consisted of a treadmill run to volitional fatigue ( approximately 120 min) performed on three consecutive days. Fifteen minutes after the last bout of exercise or rest, mice (n=20-21/group) were intranasally inoculated with a standardized dose of influenza virus (0.25 HAU). Mice were monitored daily for morbidity (time to sickness), symptom severity and mortality (time to death) for 21 days. Exercise stress was associated with an increase in susceptibility to infection (morbidity, mortality and symptom severity on days 6 and 7; P<0.05). These data from a controlled influenza virus challenge model add significantly to the growing body of evidence that severe exercise can increase susceptibility to URTI.


Asunto(s)
Subtipo H1N1 del Virus de la Influenza A/inmunología , Infecciones por Orthomyxoviridae/inmunología , Estrés Fisiológico/inmunología , Análisis de Varianza , Animales , Peso Corporal/inmunología , Susceptibilidad a Enfermedades/inmunología , Masculino , Ratones , Ratones Endogámicos ICR , Condicionamiento Físico Animal , Esfuerzo Físico , Índice de Severidad de la Enfermedad
7.
Am J Physiol Regul Integr Comp Physiol ; 295(2): R505-9, 2008 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-18579649

RESUMEN

Exercise stress is associated with increased risk for upper respiratory tract infection. We have shown that exercise stress can increase susceptibility to infection. Quercetin, a flavonoid present in a wide variety of fruits and vegetables, has been reported to inhibit infectivity and replication of a broad spectrum of viruses and may offset the increase in susceptibility to infection associated with stressful exercise. This study examined the effects of quercetin feedings on susceptibility to the influenza virus A/Puerto Rico/8/34 (H1N1) following stressful exercise. Mice were randomly assigned to one of four treatment groups: exercise-placebo, exercise-quercetin, control-placebo, or control-quercetin. Exercise consisted of a run to fatigue (approximately 140 min) on a treadmill for 3 consecutive days. Quercetin (12.5 mg/kg) was administered via gavage for 7 days before viral challenge. At 30 min after the last bout of exercise or rest, mice (n=23-30) were intranasally inoculated with a standardized dose of influenza virus (0.04 hemagglutinating units). Mice were monitored daily for morbidity (time to sickness), symptom severity, and mortality (time to death) for 21 days. Exercise stress was associated with an increased susceptibility to infection [morbidity, mortality, and symptom severity on days 5-7 (P<0.05)]; quercetin offset the increase in susceptibility to infection [morbidity, mortality, and symptom severity on days 5-7 (P<0.05)] that was associated with stressful exercise. These data suggest that short-term quercetin feedings may prove to be an effective strategy to lessen the impact of stressful exercise on susceptibility to respiratory infection.


Asunto(s)
Fenómenos Fisiológicos Nutricionales de los Animales , Antivirales/farmacología , Infecciones por Orthomyxoviridae/prevención & control , Esfuerzo Físico , Quercetina/farmacología , Infecciones del Sistema Respiratorio/prevención & control , Estrés Fisiológico/tratamiento farmacológico , Animales , Modelos Animales de Enfermedad , Susceptibilidad a Enfermedades , Subtipo H1N1 del Virus de la Influenza A/patogenicidad , Masculino , Ratones , Ratones Endogámicos ICR , Infecciones por Orthomyxoviridae/fisiopatología , Infecciones por Orthomyxoviridae/virología , Infecciones del Sistema Respiratorio/fisiopatología , Infecciones del Sistema Respiratorio/virología , Índice de Severidad de la Enfermedad , Estrés Fisiológico/complicaciones , Estrés Fisiológico/fisiopatología , Factores de Tiempo
8.
Hum Vaccin ; 4(5): 389-92, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-18437056

RESUMEN

The presence of circulating tumor cells (CTC) from various cancers has provided a wealth of information and possibilities. As the role of CTC detection in the treatment assessment of metastatic breast cancer becomes standard, there is interest in applying this tool in cancer vaccine development and clinical trial monitoring. Since we lack a proven immunologic assay that correlates with clinical response, CTC detection, quantification and phenotypic characterization may be a useful surrogate for clinical outcome. The Cancer Vaccine Development Program is involved in the development of HER2/neu peptide based vaccine development for the prevention of recurrence in HER2/neu expressing cancers like breast cancer. The CellSearch System (Veridex, LLC Warren, NJ) has been used by our lab in conjunction with in vivo and/or in vitro immunologic measurements to define a monitoring tool that could predict clinical response. Once validated, this assay could significantly shorten clinical trials and lead to more efficient assessment of potentially promising cancer vaccines.


Asunto(s)
Células Sanguíneas , Neoplasias de la Mama/diagnóstico , Neoplasias de la Mama/inmunología , Vacunas contra el Cáncer/inmunología , Biomarcadores , Recuento de Células , Humanos , Resultado del Tratamiento
9.
Am J Physiol Regul Integr Comp Physiol ; 294(5): R1593-9, 2008 May.
Artículo en Inglés | MEDLINE | ID: mdl-18353878

RESUMEN

Exercise stress is associated with an increased risk for upper respiratory tract infection (URTI). We have shown that consumption of the soluble oat fiber beta-glucan (ObetaG) can offset the increased risk for infection and decreased macrophage antiviral resistance following stressful exercise; however, the direct role of macrophages is unknown. This study examined the effect of macrophage depletion on the benefits of orally administered ObetaG on susceptibility to infection (morbidity, symptom severity, and mortality) following exercise stress. CL(2)MDP (Ex- H(2)O-CL(2)MDP, Ex-ObetaG-CL(2)MDP, Con-H(2)O-CL(2)MDP, Con-ObetaG-CL(2)MDP)-encapsulated liposomes were administered intranasally to deplete macrophages, and PBS (Ex-H(2)O-PBS, Ex-ObetaG-PBS, Con-H(2)O-PBS, Con-ObetaG-PBS)-encapsulated liposomes were given to macrophage-intact groups. Ex mice ran to volitional fatigue on a treadmill for 3 consecutive days, and ObetaG mice were fed a solution of 50% ObetaG in their drinking water for 10 consecutive days before infection. Fifteen minutes following the final bout of Ex or rest, mice were intranasally inoculated with 50 microl of a standardized dose of herpes simplex virus-1. Ex increased morbidity (P < 0.001) and symptom severity (P < 0.05) but not mortality (P = 0.09). The increase in morbidity and symptom severity was blocked by ObetaG consumption for 10 consecutive days before exercise and infection [morbidity (P < 0.001) and symptom severity (P < 0.05)]. Depletion of macrophages negated the beneficial effects of ObetaG on reducing susceptibility to infection following exercise stress, as evidenced by an increase in morbidity (P < 0.01) and symptom severity (P < 0.05). Results indicate that lung macrophages are at least partially responsible for mediating the beneficial effects of ObetaG on susceptibility to respiratory infection following exercise stress.


Asunto(s)
Fenómenos Fisiológicos Nutricionales de los Animales/fisiología , Avena/química , Pulmón/fisiología , Macrófagos/fisiología , Condicionamiento Físico Animal/fisiología , Infecciones del Sistema Respiratorio/tratamiento farmacológico , Infecciones del Sistema Respiratorio/etiología , Estrés Fisiológico , beta-Glucanos/farmacología , Analgésicos no Narcóticos/administración & dosificación , Analgésicos no Narcóticos/farmacología , Animales , Ácido Clodrónico/administración & dosificación , Ácido Clodrónico/farmacología , Dieta , Herpes Simple/tratamiento farmacológico , Herpes Simple/etiología , Herpesvirus Humano 1 , Inmunidad Celular/efectos de los fármacos , Liposomas , Pulmón/efectos de los fármacos , Macrófagos/efectos de los fármacos , Masculino , Ratones , Fatiga Muscular/fisiología , Infecciones del Sistema Respiratorio/mortalidad , Aumento de Peso/efectos de los fármacos
10.
Int J Sports Med ; 29(10): 856-63, 2008 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-18213545

RESUMEN

This study measured the influence of the flavonoid quercetin on immune changes and incidence rates of upper respiratory tract infections in ultramarathoners competing in the 160-km Western States Endurance Run. Sixty-three runners were randomized to quercetin and placebo groups, and under double-blinded methods ingested 1000 mg/day quercetin for 3 wks before, during, and 2 wks after the race. Thirty-nine of the 63 subjects (n = 18 for quercetin, n = 21 for placebo) finished the race and provided blood and saliva samples the morning before the race and 15 - 30 min postrace. Upper respiratory tract infections were assessed during the week before and the 2-wk period after the race using an illness symptom checklist. Race times did not differ significantly between quercetin and placebo groups. Significant pre- to postrace decreases were measured for natural killer cells (43 %), granulocyte respiratory burst activity (55 %), and salivary IgA output (48 %), and increases for neutrophil (288 %) and monocyte (211 %) cell counts, with no significant group differences. Postrace illness rates did not differ between groups. In conclusion, quercetin supplementation for 3 wks before and 2 wks after the Western States Endurance Run had no effect on illness rates, perturbations in leukocyte subset counts, or decreases in granulocyte respiratory burst activity and salivary IgA.


Asunto(s)
Antioxidantes/farmacología , Granulocitos/efectos de los fármacos , Inmunoglobulina A/análisis , Quercetina/farmacología , Estallido Respiratorio/efectos de los fármacos , Infecciones del Sistema Respiratorio/prevención & control , Adulto , Antioxidantes/administración & dosificación , Antioxidantes/uso terapéutico , Femenino , Granulocitos/fisiología , Humanos , Masculino , Persona de Mediana Edad , Quercetina/administración & dosificación , Quercetina/uso terapéutico , Estallido Respiratorio/fisiología , Infecciones del Sistema Respiratorio/epidemiología , Infecciones del Sistema Respiratorio/inmunología , Carrera/fisiología , Glándulas Salivales/metabolismo , Deportes
11.
J Appl Physiol (1985) ; 103(5): 1592-7, 2007 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-17823297

RESUMEN

Exhaustive exercise has been associated with an increased risk for upper respiratory tract infections in mice and humans. We have previously shown (Brown AS, Davis JM, Murphy AE, Carmichael MD, Ghaffer A, Mayer EP. Med Sci Sports Exerc 36: 1290-1295, 2004) that female mice are better protected from the lethal effects of herpes simplex virus type 1 (HSV-1) infection, both at rest and following exercise stress, but little is known about possible mechanisms. This study tested the effects of estrogen on HSV-1 infection and macrophage antiviral resistance following repeated exhaustive exercise. Female mice were assigned to either exercise (Ex) or control (C): intact female (I-C or I-Ex), ovariectomized female (O-C or O-Ex), or ovariectomized estrogen-supplemented female (E-C or E-Ex). Exercise consisted of treadmill running to volitional fatigue ( approximately 125 min) for 3 consecutive days. Intact female mice had a later time to death than O and E (P < 0.05) and fewer deaths than both O and E (P < 0.05). Exercise stress was associated with increased time to sickness (P < 0.05) and symptom severity at days 6 and 12-21 postinfection (P < 0.05) and decreased macrophage antiviral resistance (P < 0.001) in all groups. E had increased symptom severity at days 6 and 13-21 postinfection (P < 0.05). Results indicate that intact female mice are better protected from the lethal effects of HSV-1 infection and that exercise stress had a similar negative impact in all groups. This protective effect was lost in ovariectomized mice, but it was not reinstated by 17beta-estradiol replacement. This indicates that other ovarian factors, alone or in combination with estrogen, are responsible for the protective effects in females.


Asunto(s)
Estradiol/metabolismo , Herpes Simple/metabolismo , Herpesvirus Humano 1/patogenicidad , Esfuerzo Físico , Estrés Fisiológico/complicaciones , Animales , Peso Corporal , Supervivencia Celular , Células Cultivadas , Modelos Animales de Enfermedad , Implantes de Medicamentos , Estradiol/administración & dosificación , Estradiol/sangre , Femenino , Herpes Simple/patología , Herpes Simple/fisiopatología , Herpes Simple/virología , Macrófagos Peritoneales/metabolismo , Macrófagos Peritoneales/virología , Ratones , Tamaño de los Órganos , Ovariectomía , Índice de Severidad de la Enfermedad , Estrés Fisiológico/metabolismo , Estrés Fisiológico/patología , Estrés Fisiológico/fisiopatología , Factores de Tiempo , Útero/metabolismo , Útero/patología
12.
Int J Clin Pract ; 61(3): 373-8, 2007 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-17263699

RESUMEN

Endovascular aneurysm repair (EVAR) has become an established alternative to open repair (OR). We present a consecutive series of 486 elective patients with large infra-renal aortic abdominal aneurysm, comparing OR with EVAR. Prospective data collected during an 8-year period from January 1997 to October 2005 was reviewed. Statistical analysis performed using SPSS data editor with chi(2) tests and Mann-Whitney U-tests. There were 486 patients with 329 OR (293 males, 36 females) with median age of 72 years with median diameter 6.3 cm and 157 EVAR (148 males, 9 females) with median age 75 years with median diameter 6.1 cm. Mortality was 13 (4%) for OR and 5 (3.2%) for EVAR (three of whom were in the UK EVAR 2 trial). Blood loss was significantly less for EVAR 500 ml vs. 1500 ml for OR. Sixty-five (19.8%) patients with OR had significantly more peri-operative complications compared with 14 (8.9%) with EVAR. The length of stay in hospital was significantly less for EVAR. This non-randomised study shows that although EVAR does not have a statistically significantly lower mortality, it does have statistically significantly lower complication rates compared with OR. EVAR can be achieved with good primary success, but long-term follow-up is essential to assess durability.


Asunto(s)
Aneurisma de la Aorta Abdominal/cirugía , Complicaciones Intraoperatorias/etiología , Arteria Renal/cirugía , Procedimientos Quirúrgicos Vasculares/métodos , Anciano , Aneurisma de la Aorta Abdominal/mortalidad , Implantación de Prótesis Vascular , Estudios de Cohortes , Femenino , Humanos , Tiempo de Internación , Masculino , Complicaciones Posoperatorias/etiología , Estudios Prospectivos , Resultado del Tratamiento , Procedimientos Quirúrgicos Vasculares/mortalidad
13.
Am J Physiol Regul Integr Comp Physiol ; 287(6): R1354-8, 2004 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-15308485

RESUMEN

Moderate exercise training is associated with a decreased risk for upper respiratory tract infection in human and animal studies, but the mechanisms have not been elucidated. Lung macrophages play an important role in resistance to respiratory infection, and moderate exercise can enhance macrophage antiviral resistance, but no studies have directly tested the role of lung macrophages in this response. This study tested the effect of lung macrophage depletion on susceptibility to infection following short-term moderate exercise training. Mice were assigned to one of four groups: exercise (Ex) and resting controls (Con) with and without clodronate encapsulated liposomes (CL(2)MDP-lip). Ex mice ran for 1 h on a treadmill for 6 days at 36 m/min, 8% grade. Fifteen minutes following exercise or rest on the last day of training, mice were intranasally inoculated with a standardized dose of herpes simplex virus type 1. Clodronate (Ex-CL(2)MDP-lip and Con-CL(2)MDP-lip) or PBS liposomes (Ex-PBS-lip and Con-PBS-lip) (100 microl) were intranasally administered following exercise or rest on the 4th day of training and again on the 4th day postinfection. Morbidity, mortality, and symptom severity were monitored for 21 days. Exercise decreased morbidity by 36%, mortality by 61%, and symptom severity score on days 5-7 (P < 0.05). Depletion of lung macrophages negated the beneficial effects of moderate exercise. This was indicated by no differences between Ex-CL(2)MDP-lip and Con-PBS-lip in morbidity (89 vs. 95%), mortality (79 vs. 95%), or symptom severity. Results indicate that lung macrophages play an important role in mediating the beneficial effects of moderate exercise on susceptibility to respiratory infection.


Asunto(s)
Herpes Simple/fisiopatología , Pulmón/fisiopatología , Macrófagos Alveolares/fisiología , Condicionamiento Físico Animal , Infecciones del Sistema Respiratorio/fisiopatología , Animales , Muerte , Susceptibilidad a Enfermedades , Herpesvirus Humano 1 , Masculino , Ratones , Consumo de Oxígeno , Factores de Tiempo
14.
J Appl Physiol (1985) ; 97(3): 955-9, 2004 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-15145923

RESUMEN

Both moderate exercise and the soluble fiber beta-glucan can have beneficial effects on the initiation and growth of tumors, but the data are limited, and there is no information on their combined effects. This study tested the independent and combined effects of short-term moderate-exercise training and the soluble oat fiber beta-glucan (ObetaG) on the metatastic spread of injected tumor cells and macrophage antitumor cytotoxicity. Male C57BL/6 mice were assigned to one of four groups: exercise (Ex)-H2O, Ex-ObetaG, control (Con)-H2O, or Con-ObetaG. ObetaG was fed in the drinking water for 10 days before tumor administration and death. Exercise consisted of treadmill running (1 h/day) for 6 days. After rest or exercise on the last day of training, syngeneic B16 melanoma cells (2 x 10(5)) were administered via intravenous injection (n = 8-11 per group). Lungs were removed 14 days later, and tumor foci were counted. Additional mice (n = 8 per group) were killed, and peritoneal macrophages were assayed for cytotoxicity against the same mouse tumor cell line at various effector-to-target ratios. Both moderate exercise and ObetaG decreased lung tumor foci and increased macrophage cytotoxicity. However, there were no differences in lung tumor foci and macrophage cytotoxicity between Ex-ObetaG and either Ex-H2O or Con-ObetaG. These data suggest that, although not additive in their effects, both short-term moderate-exercise training and consumption of the soluble ObetaG can decrease the metatastic spread of injected B16 melanoma cells, and these effects may be mediated in part by an increase in macrophage cytotoxicity to B16 melanoma.


Asunto(s)
Citotoxicidad Inmunológica/inmunología , Terapia por Ejercicio/métodos , Neoplasias Pulmonares/secundario , Neoplasias Pulmonares/terapia , Activación de Macrófagos/inmunología , beta-Glucanos/uso terapéutico , Administración Oral , Animales , Terapia Combinada , Citotoxicidad Inmunológica/efectos de los fármacos , Suplementos Dietéticos , Neoplasias Pulmonares/inmunología , Neoplasias Pulmonares/prevención & control , Activación de Macrófagos/efectos de los fármacos , Masculino , Melanoma/inmunología , Melanoma/prevención & control , Melanoma/secundario , Melanoma/terapia , Ratones , Ratones Endogámicos C57BL , Condicionamiento Físico Animal/métodos , Resultado del Tratamiento
15.
Am J Physiol Regul Integr Comp Physiol ; 286(2): R366-72, 2004 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-14551169

RESUMEN

Both moderate exercise and the soluble oat fiber beta-glucan can increase immune function and decrease risk of infection, but no information exists on their possible combined effects. This study tested the effects of moderate exercise and oat beta-glucan on respiratory infection, macrophage antiviral resistance, and natural killer (NK) cell cytotoxicity. Mice were assigned to four groups: exercise and water, exercise and oat beta-glucan, control water, or control oat beta-glucan. Oat beta-glucan was fed in the drinking water for 10 days before intranasal inoculation of herpes simplex virus type 1 (HSV-1) or euthanasia. Exercise consisted of treadmill running (1 h/day) for 6 days. Macrophage resistance to HSV-1 was increased with both exercise and oat beta-glucan, whereas NK cell cytotoxicity was only increased with exercise. Exercise was also associated with a 45 and 38% decrease in morbidity and mortality, respectively. Mortality was also decreased with oat beta-glucan, but this effect did not reach statistical significance. No additive effects of exercise and oat beta-glucan were found. These data confirm a positive effect of both moderate exercise and oat beta-glucan on immune function, but only moderate exercise was associated with a significant reduction in the risk of upper respiratory tract infection in this model.


Asunto(s)
Avena/química , Glucanos/farmacología , Herpes Simple/inmunología , Sistema Inmunológico/efectos de los fármacos , Sistema Inmunológico/fisiología , Actividad Motora/fisiología , Infecciones del Sistema Respiratorio/inmunología , beta-Glucanos , Fenómenos Fisiológicos Nutricionales de los Animales , Animales , Citotoxicidad Inmunológica , Susceptibilidad a Enfermedades , Glucanos/aislamiento & purificación , VIH-1/inmunología , Herpes Simple/epidemiología , Herpes Simple/mortalidad , Incidencia , Células Asesinas Naturales/inmunología , Macrófagos Peritoneales/inmunología , Masculino , Ratones , Ratones Endogámicos , Infecciones del Sistema Respiratorio/epidemiología , Infecciones del Sistema Respiratorio/mortalidad , Factor de Necrosis Tumoral alfa/metabolismo , Aumento de Peso
16.
Gen Comp Endocrinol ; 117(2): 218-24, 2000 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-10642444

RESUMEN

There are few published reports of an alternative, less invasive method than blood sampling to obtain reproductive hormone concentrations from captive dolphins. The aims of this study were to: (1) validate milk as an effective alternative to blood plasma for determining progesterone concentrations; and (2) utilize milk samples collected frequently to obtain progesterone concentration profiles and determine reproductive status. During the course of this study 16 plasma/milk sample pairs were collected from four adult bottlenose dolphins to correlate plasma and milk concentrations of progesterone. Milk samples were also collected approximately weekly for 4-5 months during three independent lactational periods. Additionally, milk samples were collected daily for approximately 1 year during three other independent lactational periods. A highly significant correlation was found between progesterone concentrations in plasma and milk (r(2) = 0.91, P < 0. 01). Progesterone contained in milk whey, fat, and solids were 3.95 +/- 1.3, 8.5 +/- 1.1, and 52.0 +/- 0.6%, respectively. Progesterone profiles from milk samples collected from two dolphins during 1995 indicated pregnancies (with progesterone concentrations between 8 and 46.5 ng/ml) which resulted in parturition. High progesterone concentrations in a third dolphin that did not give birth indicated a possible pseudopregnancy or fetal resorption. A possible ovulation not resulting in pregnancy was evident in one female in 1998, follicular activity in another female in 1998, and a year-long anestrous period in the third animal studied in 1998. It is confirmed that dolphins can become pregnant while lactating and that the approximate time of conception is identifiable in milk profiles, illustrating the potential application of this method in pregnancy detection and reproductive monitoring.


Asunto(s)
Delfines/metabolismo , Leche/metabolismo , Progesterona/metabolismo , Reproducción/fisiología , Anestro/metabolismo , Animales , Femenino , Leche/química , Periodo Posparto/metabolismo , Embarazo , Factores de Tiempo
17.
Am J Physiol ; 274(6): C1661-6, 1998 06.
Artículo en Inglés | MEDLINE | ID: mdl-9611132

RESUMEN

To assess the role of distal nephron apical Na channel (ENaC) gene expression in Na wasting by the immature kidney, ENaC alpha-, beta-, and gamma-subunit mRNA levels were examined in the rat by RT-PCR. In microdissected nephron segments, all three ENaC subunit mRNAs were detected in the distal convoluted tubule, connecting tubule, cortical collecting duct, and outer medullary collecting duct. The inner medullary collecting duct and all other nephron segments were consistently negative. The mRNA levels were quantified in kidneys at different developmental stages by multiplex RT-PCR with "primer dropping," with endoplasmic reticulum-specific cyclophilin mRNA as an internal standard. All three ENaC mRNA levels were low or undetectable on gestational day 16 and only slightly higher 3 days before birth. A sharp rise was observed between 3 days before and 1-3 days after birth; the levels at postnatal days 1-3 were already similar to those of adult kidneys. The results suggest that ENaC subunit gene expression is not a limiting factor in the full-term newborn rat kidney, but low levels of expression may limit distal Na absorption in more immature kidneys, such as those of very premature human infants.


Asunto(s)
Regulación del Desarrollo de la Expresión Génica , Riñón/crecimiento & desarrollo , ARN Mensajero/metabolismo , Canales de Sodio/genética , Animales , Animales Recién Nacidos , Riñón/embriología , Riñón/metabolismo , Reacción en Cadena de la Polimerasa , ADN Polimerasa Dirigida por ARN , Ratas , Ratas Sprague-Dawley
18.
Pediatr Res ; 39(1): 176-9, 1996 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-8825406

RESUMEN

Measurements of body composition are being made increasingly widely in pediatrics. Tetrapolar whole body impedance (BI) is particularly suitable as a method of estimating body composition in children and is therefore the subject of great interest at present. However, the ability of BI to accurately estimate fat-free mass (FFM) in children is unclear, and users of BI are faced with a growing choice of prediction equations for estimation of FFM. Studies in adults have suggested that choice of prediction equation can have a profound effect on the estimate obtained. The aim of the present study was to measure the ability of four published pediatric BI equations to predict FFM in 98 Caucasian prepubertal children (mean age 9.0 y). For three of the published equations, limits of agreement between predicted and reference FFM were wide and distinct biases were apparent. With mean FFM of 25 kg, the equation of L. Cordain et al. overestimated reference FFM (95% CI +2.1 to +3.1 kg), whereas those of P. Deurenberg et al. (95% CI -1.9 to -2.9 kg) and F. Schaefer et al. (95% CI -1.4 to -2.5 kg) systematically underestimated reference FFM. The equation of Houtkooper et al. (95% CI -0.2 to +0.8 kg) predicted FFM with negligible bias and had narrower limits of agreement relative to the reference method than the other three equations tested. We conclude that the ability of BI to predict body composition in children depends on the equation chosen and that the general applicability of BI equations cannot be safely assumed. Cross-validation of BI equations is recommended before they are used routinely for estimation of body composition in children.


Asunto(s)
Composición Corporal , Impedancia Eléctrica , Cómputos Matemáticos , Niño , Densitometría , Femenino , Humanos , Masculino
19.
J Urol ; 153(3 Pt 2): 1015-9, 1995 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-7853549

RESUMEN

Deoxyribonucleic acid (DNA) ploidy image analysis was used postoperatively to predict recurrence of 112 clinically localized adenocarcinomas of the prostate. All men underwent radical retropubic prostatectomy between 1978 and 1991. Patients with positive lymph nodes or positive seminal vesicles were excluded because progression is nearly inevitable in these men. The minimum followup for men without progression was 5 years (range 5 to 15). Patients were considered to have clinically evident disease progression based on local recurrence (8%), distant metastases (4%) and/or an isolated elevation of serum prostate specific antigen (87%). Of the tumors 43% were diploid and 57% were nondiploid. In a multivariate analysis comparing grade, ploidy, capsular penetration and surgical margins, Gleason sum was the best predictor of progression (p < 0.0001). Nevertheless, a subset of patients remained with well to moderately differentiated Gleason grade tumors (Gleason sum 6 or less) who failed. DNA ploidy was able to predict recurrence in this particular group (p = 0.034). In addition, we compared different methods of tissue preparation to determine which best predicted progression. We found that ploidy analysis on tissue sections was more predictive than ploidy performed on disaggregated tissue. In summary, our study revealed that DNA ploidy analysis can offer additional prognostic information following radical prostatectomy for men with low grade prostatic adenocarcinoma.


Asunto(s)
Adenocarcinoma/patología , Adenocarcinoma/cirugía , ADN de Neoplasias/análisis , Recurrencia Local de Neoplasia/patología , Ploidias , Prostatectomía , Neoplasias de la Próstata/patología , Neoplasias de la Próstata/cirugía , Análisis Actuarial , Adenocarcinoma/genética , Estudios de Seguimiento , Humanos , Masculino , Análisis Multivariante , Recurrencia Local de Neoplasia/epidemiología , Recurrencia Local de Neoplasia/genética , Estadificación de Neoplasias , Valor Predictivo de las Pruebas , Neoplasias de la Próstata/genética
20.
J Urol ; 153(3 Pt 2): 987-92, 1995 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-7853589

RESUMEN

The aim of this study was to characterize the pathological features of hereditary prostate cancer, a recently recognized variant of prostate cancer with an autosomal dominant inheritance of a rare highly penetrant gene associated with early onset of disease. We compared the histology at radical prostatectomy of clinical stage T2 prostate cancer, including its relationship to prostatic intraepithelial neoplasia, in men with a family history of prostate cancer to those without a family history of prostate cancer. Three cohorts (hereditary, familial and sporadic) were identified based on pedigree analysis. A hereditary subgroup (28 patients) met 1 of the following 3 criteria: 1) cluster of greater than 3 affected relatives within the nuclear family, 2) occurrence of prostate cancer in each of 3 generations in either the proband paternal or maternal lineage, or 3) a cluster of 2 relatives affected at an early age of less than 55 years. This subgroup was compared to an age-matched subgroup with family history of prostate cancer (26 patients) yet the aforementioned conditions for inclusion within the hereditary subgroup were not met and to a sporadic subgroup without a family history of prostate cancer (27 patients). All parameters were statistically similar among the groups except that hereditary and familial group multifocal tumors were of lower grade (p = 0.0001), sporadic cases had a greater proportion of small multifocal cancers associated with prostatic intraepithelial neoplasia (p = 0.02) and the familial group had a weaker correlation between total tumor volume and grade. In conclusion, our analysis failed to demonstrate substantial pathological differences among hereditary, familial and sporadic forms of prostate cancer. Rather, our data are remarkable for the wide range of all parameters studied in each group. Even the sporadic cases had features, such as increased numbers of precursor lesions and tumor multifocality, which in other organs are commonly associated with either hereditary cancer or cancer arising in a field effect due to diffuse exposure to a carcinogen.


Asunto(s)
Adenocarcinoma/genética , Adenocarcinoma/patología , Neoplasias de la Próstata/genética , Neoplasias de la Próstata/patología , Estudios de Cohortes , Humanos , Masculino , Persona de Mediana Edad , Invasividad Neoplásica , Estadificación de Neoplasias
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