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1.
Vet J ; 307: 106203, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-39069166

RESUMEN

Virtual reality (VR)-based training has shown some benefits in medical education, supporting skill acquisition, and helping reduce anxiety in real-world settings. However, the use of VR simulators in veterinary education remains limited. This study aimed to introduce a VR simulator to support veterinarian training in canine anaesthesia induction and endotracheal intubation. This study involved a group that learned solely with instructional videos (video group), and one that learned concurrently with the video and VR simulator (VR group). Third- and fourth-year veterinary students were included and underwent a descriptive test on canine endotracheal intubation. Canine endotracheal intubation success rates were compared between the video (n = 364) and VR (n = 60) groups of fifth-year students. A survey on the VR usability was conducted (n=91). The median descriptive test scores improved in the VR (63.3/100) vs the video group (51.5/100). The canine intubation success rates were comparable in the VR and video groups at 84.3 % and 77.4 %, respectively. A total of 90.1 % of the surveyed students rated the ease of use of the simulator highly. Overall, VR simulators were well-received, suggesting benefits in new skill retention. Further studies are required to evaluate the extent of skill improvement through VR-based training, compared to conventional methods, and to assess its impact on student motivation. Evaluating the long-term effects of VR-based training on skill development and retention will also provide a deeper understanding of its educational benefits.


Asunto(s)
Educación en Veterinaria , Intubación Intratraqueal , Realidad Virtual , Animales , Perros , Educación en Veterinaria/métodos , Intubación Intratraqueal/veterinaria , Intubación Intratraqueal/métodos , Humanos , Competencia Clínica , Masculino , Femenino , Simulación por Computador
2.
J Neuropathol Exp Neurol ; 48(5): 577-90, 1989 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-2769310

RESUMEN

A spontaneous spongy degeneration of the brain stem and spinal cord was discovered in a murine model of accelerated senescence (SAM), cared for under both conventional (SAM-P/8) and specific pathogen-free (SAM-P/8/Ta) conditions. SAM-P/8 and SAM-P/8/Ta showed no clinical neurological abnormalities, yet there was a deterioration in learning and memory abilities. Light microscopic examination revealed a spongy degeneration in the brain stem and spinal cord, in the reticular formation, and proliferation of hypertrophic astrocytes in the spongy area. The spongiform degeneration progressed with advancing age from four to eight months, after which the entire brain was involved. Astrocytosis increased with advancing degeneration. Ultrastructurally, mild dendritic swelling occurred at one month of age. At two months of age, moderate postsynaptic swelling and a widening of intracellular membrane structure were observed, and at age five months there were large vacuoles circumscribed by membranous lamellae, identifiable as myelin. Vacuoles in SAM-P/8 proved to be swollen neuronal processes and oligodendroglial processes. These SAM-P/8 and SAM-P/8/Ta strains of mice are new memory-deficient strains with spontaneous spongy degeneration associated with aging.


Asunto(s)
Tronco Encefálico/patología , Trastornos de la Memoria/genética , Ratones Mutantes Neurológicos/anatomía & histología , Degeneración Nerviosa , Animales , Astrocitos/patología , Tronco Encefálico/ultraestructura , Macrófagos/patología , Trastornos de la Memoria/patología , Ratones , Microscopía Electrónica , Vaina de Mielina/ultraestructura , Orgánulos/ultraestructura , Médula Espinal/patología , Médula Espinal/ultraestructura , Vacuolas/ultraestructura
3.
Brain Res ; 669(2): 225-33, 1995 Jan 16.
Artículo en Inglés | MEDLINE | ID: mdl-7712178

RESUMEN

The senescence-accelerated mouse (SAMP8) is a model of age-related deterioration of memory and learning ability. A semipurified diet supplemented either with safflower oil (rich in linoleate) or with perilla oil (rich in alpha-linolenate) was fed to SAMP8 mouse dams and their pups. The offspring (males from several mothers) at 28 weeks of age were used for behavioral tests. The proportions of n-3 and n-6 highly unsaturated fatty acids in brain phospholipids reflected the n-3/n-6 balance of the diets. The learning and memory abilities of the two dietary groups were tested with the Sidman active avoidance task and the light and dark discrimination learning test. The group given perilla oil showed much greater improvement in learning in the Sidman active avoidance task than did the group fed safflower oil. In the light and dark discrimination learning test, the total number of responses to positive and negative stimuli was lower in those fed perilla oil, and their responses to positive stimuli were higher than to negative stimuli after the 10th session. Consequently, the correct response ratios of discrimination were higher in the perilla oil group than in the safflower oil group. In the open field test, the total amount of locomotor activity during 5 min was lower in the perilla oil group at 7 months of age than in the group fed safflower oil.(ABSTRACT TRUNCATED AT 250 WORDS)


Asunto(s)
Reacción de Prevención/efectos de los fármacos , Grasas de la Dieta/farmacología , Ácidos Linoleicos/farmacología , Memoria/efectos de los fármacos , Factores de Edad , Envejecimiento/fisiología , Animales , Reacción de Prevención/fisiología , Ritmo Circadiano/efectos de los fármacos , Ritmo Circadiano/fisiología , Grasas de la Dieta/administración & dosificación , Femenino , Ácido Linoleico , Ácidos Linoleicos/administración & dosificación , Masculino , Memoria/fisiología , Ratones , Modelos Biológicos , Aceite de Cártamo
4.
Eur J Pharmacol ; 395(3): 183-91, 2000 May 03.
Artículo en Inglés | MEDLINE | ID: mdl-10812048

RESUMEN

Arachidonic acid and nitric oxide (NO) act as retrograde and intercellular messengers in the nervous system. Regulation of cyclooxygenase is well established, but regulation of phospholipase A(2), the enzyme responsible for the liberation of arachidonic acid, by NO has not been thoroughly investigated. Using the PC12 cell line as a neuronal model, we studied the effects of exogenous NO compounds on arachidonic acid release. Incubation with Ca(2+) ionophores or mastoparan (wasp venom peptide) stimulated [3H]arachidonic acid release from prelabeled PC12 cells. [3H]Arachidonic acid release was inhibited by cytosolic phospholipase A(2) inhibitors, but not by dithiothreitol. A cytosolic phospholipase A(2) protein band with a molecular mass of approximately 100 kDa was detected by immunoblotting. S-Nitroso-cysteine inhibited basal and stimulated [3H]arachidonic acid release in concentration-dependent manners. Other NO compounds such as sodium nitroprusside and S-nitroso-N-acetylpenicillamine did not affect [3H]arachidonic acid release. N-Ethylmaleimide also inhibited [3H]arachidonic acid release. The inhibitory effects of S-nitroso-cysteine and N-ethylmaleimide were irreversible, because [3H]arachidonic acid release from PC12 cells preincubated with S-nitroso-cysteine or N-ethylmaleimide was much lower than that from nontreated cells. These findings suggest (a) cytosolic phospholipase A(2) is activated by Ca(2+) or mastoparan, and inhibited by S-nitroso-cysteine in a cyclic GMP-independent manner, (b) N-ethylmaleimide also inhibits cytosolic phospholipase A(2) and arachidonic acid release in PC12 cells. S-Nitroso-cysteine can regulate the production of other retrograde messenger arachidonic acid.


Asunto(s)
GMP Cíclico/fisiología , Cisteína/análogos & derivados , Compuestos Nitrosos/farmacología , Fosfolipasas A/antagonistas & inhibidores , S-Nitrosotioles , Animales , Ácido Araquidónico/metabolismo , Cisteína/farmacología , Citosol/enzimología , Relación Dosis-Respuesta a Droga , Activación Enzimática , Inhibidores Enzimáticos/farmacología , Etilmaleimida/farmacología , Péptidos y Proteínas de Señalización Intercelular , Células PC12 , Péptidos , Fosfolipasas A/metabolismo , Ratas , Tritio , Venenos de Avispas/farmacología
5.
Phytopathology ; 90(3): 311-6, 2000 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-18944625

RESUMEN

ABSTRACT The 50-kDa protein (P50) encoded by the open reading frame 2 of Apple chlorotic leaf spot virus (ACLSV), a putative movement protein, was expressed in transgenic Nicotiana occidentalis plants. P50 in transgenic plants was mainly detected in a modified form in the cell wall fraction, similar to that in infected leaves. The P50-expressing plants (P50 plants) complemented the systemic spread of the P50-defective mutants of an infectious cDNA clone of ACLSV (pCLSF), indicating that P50 in transgenic plants was functional. Severity of symptoms was greatly enhanced and accumulation of virus in upper leaves was increased in P50 plants inoculated with pCLSF or ACLSV compared with that in nontransgenic control plants (NT plants). Conversely, transgenic plants expressing the coat protein of ACLSV (CP plants) showed a significant delay in symptom development and a reduction of virus accumulation. However, most P50 plants inoculated with Grapevine berry inner necrosis virus (GINV), another species of the genus Trichovirus, neither developed obvious symptoms nor supported virus accumulation in inoculated or upper leaves. In contrast, systemic symptoms developed and virus accumulated equally in NT and CP plants inoculated with GINV. After inoculation with Apple stem grooving virus or Apple stem pitting virus, there was no difference in symptom development and virus accumulation among P50, CP, and NT plants. Our results indicate that transgenic plants expressing a functional P50 were more susceptible to homologous virus and, on the contrary, showed strong resistance to the heterologous virus GINV.

6.
Phys Med ; 30(5): 555-8, 2014 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-24786663

RESUMEN

PURPOSE: Spot-scanning proton beam therapy (PBT) can create good dose distribution for static targets. However, there exists larger uncertainty for tumors that move due to respiration, bowel gas or other internal circumstances within the patients. We have developed a real-time tumor-tracking radiation therapy (RTRT) system that uses an X-ray linear accelerator gated to the motion of internal fiducial markers introduced in the late 1990s. Relying on more than 10 years of clinical experience and big log data, we established a real-time image gated proton beam therapy system dedicated to spot scanning. MATERIALS AND METHODS: Using log data and clinical outcomes derived from the clinical usage of the RTRT system since 1999, we have established a library to be used for in-house simulation for tumor targeting and evaluation. Factors considered to be the dominant causes of the interplay effects related to the spot scanning dedicated proton therapy system are listed and discussed. RESULTS/CONCLUSIONS: Total facility design, synchrotron operation cycle, and gating windows were listed as the important factors causing the interplay effects contributing to the irradiation time and motion-induced dose error. Fiducial markers that we have developed and used for the RTRT in X-ray therapy were suggested to have the capacity to improve dose distribution. Accumulated internal motion data in the RTRT system enable us to improve the operation and function of a Spot-scanning proton beam therapy (SSPT) system. A real-time-image gated SSPT system can increase accuracy for treating moving tumors. The system will start clinical service in early 2014.


Asunto(s)
Imagen Molecular , Movimiento , Neoplasias/radioterapia , Terapia de Protones/métodos , Diseño de Equipo , Marcadores Fiduciales , Humanos , Neoplasias/fisiopatología , Aceleradores de Partículas , Terapia de Protones/instrumentación , Terapia de Protones/normas , Dosis de Radiación , Factores de Tiempo
7.
Med Phys ; 39(6Part16): 3795, 2012 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-28517231

RESUMEN

PURPOSE: The purpose was to investigate the interplay of residual motion in realistically delivered respiratory gated spot scanning proton beam by a synchrotron. METHODS: A MatriXX 2D ion-chamber array detector was placed on a moving platform. The platform with the 2D ion-chamber array detector was moved based on sin4 motion with 3s and 5s cycle and 20 mm amplitude. Its motion was monitored by a laser displacement sensor (ZS-LDS2VT, omron, Japan). The respiration gate threshold level was set at 30% duty cycle and the residual motion within the gate window was approximately 6 mm. A 10×10 cm2 uniform field was delivered by a matrix of 13×13 spots with ∼ 8 mm spot size (s) and 8 mm spot spacing. Measurements were done for the field delivered with a single painting and multiple re-painting, from 2 to 12 times, for both orthogonal and parallel scan directions. The same field was also measured without moving the detector, defined as the static reference dose. Dose homogeneity was compared between with gated and the static dose distributions. RESULTS: The worst single painting result of the dose homogeneity ratio was 0.90 in 3s motion cycle and 0.93 in 5s motion cycle with the orthogonal scan pattern, and 0.97 in 3s and 0.98 in 5s motion with the parallel scan pattern, respectively . The homogeneity ratio improved to over 0.98 by 4∼6 times repainting in orthogonal and only 2 times re-painting with the parallel scan. CONCLUSIONS: The respiratory gated spot scanning proton beam delivery is sensitive to spot movement direction relative to the residual motion of the target. A proper selection of the number of repainting and the scan direction can improve beam delivery quality. The study offers a basic understanding when implementing respiratory gated spot scanning proton beam treatment.

10.
J Nutr ; 123(11): 1905-12, 1993 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-8229307

RESUMEN

The effects of replacing dietary casein with soybean protein on mean life span, mean life span of the last one-tenth of a group, grading scores of senescence and deposition of senile amyloid were investigated in senescence accelerated mice (SAM-P/1) compared with a control strain (SAM-R/1). SAM-R/1 mice fed the soybean protein-containing diet had mean life spans of 618 +/- 42 d (males) and 578 +/- 62 d (females), 58% (males) and 44% (females) longer than those of corresponding casein fed mice (P < 0.01). Similarly, in SAM-P/1 mean life-spans were 265 +/- 16 d (males) and 307 +/- 23 d (females) in the soybean diet group, 27% (males) and 30% (females) longer than in the casein diet groups (P < 0.01). The mean life span of the last one-tenth of each group fed soybean protein was significantly longer than the corresponding group fed casein. In SAM-R/1 mice, pathological studies revealed that severe secondary amyloid deposition (amyloid A protein) in the kidneys, spleen, stomach and liver was significantly suppressed, in males only, by replacing casein with soybean protein (P < 0.01). The occurrence of contracted kidneys caused by the infiltration of amyloid A protein was suppressed in SAM-R/1 mice fed the soybean protein-containing diet (P < 0.05). The deposition of senile amyloid in SAM-P/1 mice with aging was retarded by replacing casein with soybean protein (P < 0.01). These results indicate that dietary protein source is important in modulating the advance of senescence in SAM mice.


Asunto(s)
Envejecimiento/efectos de los fármacos , Caseínas/farmacología , Proteínas en la Dieta/farmacología , Glycine max , Envejecimiento/patología , Amiloide/metabolismo , Animales , Peso Corporal/efectos de los fármacos , Femenino , Masculino , Ratones , Ratones Endogámicos , Tasa de Supervivencia
11.
Lab Anim Sci ; 48(3): 256-63, 1998 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-10090025

RESUMEN

Age-related changes in systolic blood pressure were assessed, using the senescence-accelerated mouse (SAM) model for aging research with strains SAMR1, SAMP1, and SAMP8. Each of the strains manifested a characteristic change in blood pressure with age. The SAMR1 strain, with normal aging, did not have chronologic changes from 2 to 27 months of age. The SAMP1 strain, with accelerated senescence, had a significant increase in blood pressure with age, and some (8 of 39) mice manifested hypertensive vascular disease characterized by high blood pressure, cardiac hypertrophy, and arteriolar fibrinoid necrosis at 11 to 14 months of age. The gradual increase in blood pressure after 8 to 10 months was considered to be preceded by progressive renal changes, from glomerulonephritis to contraction of the kidney, suggesting that the high blood pressure in the SAMP1 strain was of renal origin. Blood pressure in the SAMP8 strain, with age-related deficits in learning and memory, gradually decreased after 5 to 7 months of age, and was suggested to be due to the astrogliotic changes in response to spongiform degeneration in the medulla oblongata at 11 to 14 and 15 to 18 months of age.


Asunto(s)
Envejecimiento/fisiología , Presión Sanguínea/fisiología , Hipertensión Renal/fisiopatología , Envejecimiento Prematuro/genética , Animales , Arteriolas/patología , Modelos Animales de Enfermedad , Femenino , Hipertensión Renal/genética , Hipertensión Renal/patología , Glomérulos Renales/patología , Masculino , Bulbo Raquídeo/patología , Ratones , Ratones Endogámicos , Miocardio/patología , Tamaño de los Órganos/fisiología , Especificidad de la Especie , Resistencia Vascular/fisiología
12.
Bone Miner ; 7(1): 1-12, 1989 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-2765711

RESUMEN

Inter-strain differences in bone mass and density during growth were followed in three strains of mice: SAM-P/2, SAM-R/1 and SAM-P/6 (a murine model of senile osteoporosis, Matsushita et al., Am J Pathol 1986;125:276-283). Photometrically, the inter-strain disparities first appeared in mice at about age 28 days and increased until age 60 days. During this period, tetracycline labelling revealed significant strain differences regarding rate of the appositional formation at the endosteal surface but not at the periosteal surface. The order coincided with results of the photometrical assay, that is, highest in SAM-P/2, followed by SAM-R/1 and SAM-P/6, respectively. Therefore, strain differences, especially the osteopenic state of SAM-P/6, occur, at least in part, by disparities in endosteal formation rates during cortical bone modelling.


Asunto(s)
Desarrollo Óseo , Envejecimiento , Animales , Huesos/citología , Huesos/diagnóstico por imagen , Fémur/anatomía & histología , Masculino , Ratones , Ratones Mutantes , Tamaño de los Órganos , Radiografía , Tetraciclina
13.
J Nutr ; 129(2): 431-7, 1999 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-10024623

RESUMEN

Semipurified diets incorporating either perilla oil [high in alpha-linolenate, 18:3(n-3)] or safflower oil [high in linoleate, 18:2(n-6)] were fed to senescence-resistant SAMR1 mouse dams and their pups. Male offspring at 15 mo were examined using behavioral tests. In the open field test, locomotor activity during a 5-min period was significantly higher in the safflower oil group than in the perilla oil group. Observations of the circadian rhythm (48 h) of spontaneous motor activity indicated that the safflower oil group was more active than the perilla oil group during the first and second dark periods. The total number of responses to positive and negative stimuli was higher in the safflower oil group than in the perilla oil group in the light and dark discrimination learning test, but the correct response ratio was lower in the safflower oil group. The difference in the (n-6)/(n-3) ratios of the diets reflected the proportions of (n-6) polyunsaturated fatty acids, rather than those of (n-3) polyunsaturated fatty acids in the brain total fatty acids, and in the proportions of (n-6) and (n-3) polyunsaturated fatty acids in the total polyunsaturated fatty acids of the brain phospholipids. These results suggest that in SAMR1 mice, the dietary alpha-linolenate/linoleate balance affects the (n-6)/(n-3) ratio of brain phospholipids, and this may modify emotional reactivity and learning ability.


Asunto(s)
Envejecimiento , Conducta Animal/fisiología , Grasas Insaturadas en la Dieta/administración & dosificación , Aprendizaje/fisiología , Ácido Linoleico/administración & dosificación , Ácido alfa-Linolénico/administración & dosificación , Animales , Química Encefálica , Ritmo Circadiano , Discriminación en Psicología , Ácidos Grasos Omega-3/análisis , Ácidos Grasos Omega-6 , Ácidos Grasos Insaturados/análisis , Femenino , Masculino , Ratones , Ratones Endogámicos , Actividad Motora/fisiología , Fosfolípidos/análisis , Aceites de Plantas , Aceite de Cártamo
14.
J Nutr ; 130(2): 221-7, 2000 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-10720173

RESUMEN

The senescence-accelerated mouse (SAMP8) is an animal model used in studies of aging. This study was undertaken to investigate the effects of dietary PUFA on longevity (Experiment 1) and serum lipid concentrations (Experiment 2) in SAMP8 mice. Male mice were fed either an (n-3) PUFA-rich (9 g/100 g perilla oil) or an (n-6) PUFA-rich (9 g/100 g safflower oil) diet beginning at 6 wk of age. Experiment 1: The groups did not differ in body weight gain, but those fed perilla oil had significantly lower scores of senescence relative to those fed safflower oil (P<0.05). The mean life span of mice fed perilla oil was 357+/-21 d and of those fed safflower oil, 426+/-24 d (P<0.05). Pathological studies revealed that the incidence of tumors was significantly lower in the perilla oil group than in the safflower oil group (P<0.05). Approximately half the mice fed perilla oil had died after 10 mo, and the direct causes closely connected with death could not be specified. Experiment 2: The serum total cholesterol, HDL cholesterol, triglyceride and phospholipid concentrations were significantly lower in the perilla oil group than in the safflower oil group (P<0.01). A marked decrease of serum HDL cholesterol and apolipoprotein A-II (ApoA-II)concentrations in advanced age were observed in the mice fed perilla oil (P<0.01). Ten-month-old mice fed perilla oil had a significantly greater ratio of apolipoprotein A-I (ApoA-I) to ApoA-II than those fed safflower oil. Separation of HDL subfractions revealed that the smaller HDL species were much more abundant than the larger HDL species in both dietary oil groups. These findings suggest that dietary (n-3) and (n-6) PUFA differ in their effects on serum lipid metabolism which may modulate the mean life span of SAMP8 mice fed each dietary oil.


Asunto(s)
Envejecimiento/efectos de los fármacos , Anticarcinógenos/administración & dosificación , Anticarcinógenos/uso terapéutico , HDL-Colesterol/sangre , Grasas de la Dieta/uso terapéutico , Longevidad/efectos de los fármacos , Aceite de Cártamo/uso terapéutico , Ácido alfa-Linolénico/uso terapéutico , Análisis de Varianza , Animales , Anticarcinógenos/efectos adversos , Apolipoproteínas A/sangre , Electroforesis en Gel de Poliacrilamida , Neoplasias Renales/patología , Masculino , Ratones , Modelos Biológicos , Aceites de Plantas , Aceite de Cártamo/administración & dosificación , Aceite de Cártamo/efectos adversos , Análisis de Supervivencia , Ácido alfa-Linolénico/administración & dosificación , Ácido alfa-Linolénico/efectos adversos
15.
J Nutr ; 120(11): 1393-400, 1990 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-2231028

RESUMEN

The effects of age and dietary restriction on immune response were investigated using an animal model of accelerated senescence (senescence accelerated mouse, SAM). The experimental groups consisted of control (ad libitum fed) and restricted groups (fed 60% of energy intake of the controls). Spleen weight and total number of splenic cells were significantly lower in the food-restricted group at 8 mo of age. Percentages of T (Thy-1.1+) and B (surface Ig+) cells in the splenic cells were not significantly different between the two groups. The number of direct hemolytic plaque-forming cells per 10(6) spleen cells 4 d following immunization with sheep red blood cells and dinitrophenyl-Ficoll was significantly greater in the 8-mo-old mice in the food-restricted group than in the control group. In the latter group, antibody responses Progressively decreased with age. Mitogen responses to concanavalin A and lipopolysaccharide were maintained in the food-restricted group but were depressed in the control group at 8 mo. In addition, though autoantibody to single-stranded DNA increased in the control group with advancing age, there was a steady decrease in the food-restricted group until 8 mo. Serum immunoglobulin (IgA and IgM) concentrations were significantly lower in the food-restricted group than in controls at 8 mo of age. Therefore, our results suggest that when senescence accelerated mice are subjected to food restriction, there may be a modulatory effect on the immune dysfunction associated with advancing age.


Asunto(s)
Envejecimiento/inmunología , Privación de Alimentos , Animales , Formación de Anticuerpos , Femenino , Tolerancia Inmunológica , Inmunoglobulinas/inmunología , Longevidad , Activación de Linfocitos , Masculino , Ratones , Ratones Mutantes , Bazo/inmunología
17.
Nihon Sanka Fujinka Gakkai Zasshi ; 19(4): 403-6, 1967 Apr.
Artículo en Japonés | MEDLINE | ID: mdl-5624471
18.
Phys Rev D Part Fields ; 39(12): 3672-3683, 1989 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-9959627
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