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2.
J Am Assoc Lab Anim Sci ; 54(3): 317-27, 2015 May.
Artículo en Inglés | MEDLINE | ID: mdl-26045459

RESUMEN

Retroorbital blood collection is a common technique in laboratory rodents due to the ease with which it can be performed and the sample volumes obtained for subsequent blood analyses. However, its use has been discouraged recently due to aesthetic discomfort and anecdotal reports of potential for ocular injury during blood collection. We hypothesized that a single standardized session of in-person training would be sufficient to learn the appropriate technique and minimize the likelihood for adverse outcomes. Experienced instructors (n = 2) conducted hands-on training classes to teach novice personnel (n = 40) to perform this procedure. Blood was collected from anesthetized mice (n = 40) via a capillary tube first placed at the medial canthus of the right eye and then advanced into the retroorbital space; the left retroorbital spaces served as unmanipulated controls. For comparison, the experienced instructors similarly collected blood from 40 additional mice. The tube could be inserted only once in each mouse, with the goal of obtaining 50 to 100 µL blood. Overall, 79 of 80 mice (98.8%) showed normal body condition, posture, and behavior throughout the 14-d study. Thus, any clinical observation scores pertained specifically to ocular lesions, which occurred at least once after sampling in 43 (53.8%) of the mice. Clinical and histopathologic scores of mice after bleeding did not differ between experienced and novice personnel. We conclude that a coordinated hands-on training program can provide consistent and sufficient instruction for research personnel to conduct retroorbital blood collection with competence in anesthetized laboratory mice.


Asunto(s)
Recolección de Muestras de Sangre/veterinaria , Educación en Veterinaria , Animales , Recolección de Muestras de Sangre/efectos adversos , Femenino , Masculino , Ratones , Ratones Endogámicos C57BL , Órbita/patología , Medicina Veterinaria
3.
J Orthop Res ; 33(6): 882-8, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-25876927

RESUMEN

Patients with classic (type I) Ehlers-Danlos syndrome (EDS), characterized by heterozygous mutations in the Col5a1 and Col5a2 genes, exhibit connective tissue hyperelasticity and recurrent joint dislocations, indicating a potential regulatory role for collagen V in joint stabilizing soft tissues. This study asked whether the contribution of collagen V to the establishment of mechanical properties is tissue dependent. We mechanically tested four different tissues from wild type and targeted collagen V-null mice: the flexor digitorum longus (FDL) tendon, Achilles tendon (ACH), the anterior cruciate ligament (ACL), and the supraspinatus tendon (SST). Area was significantly reduced in the Col5a1(ΔTen/ΔTen) group in the FDL, ACH, and SST. Maximum load and stiffness were reduced in the Col5a1(ΔTen/ΔTen) group for all tissues. However, insertion site and midsubstance modulus were reduced only for the ACL and SST. This study provides evidence that the regulatory role of collagen V in extracellular matrix assembly is tissue dependent and that joint instability in classic EDS may be caused in part by insufficient mechanical properties of the tendons and ligaments surrounding each joint.


Asunto(s)
Tendón Calcáneo/fisiología , Ligamento Cruzado Anterior/fisiología , Colágeno Tipo V/fisiología , Animales , Fenómenos Biomecánicos , Masculino , Ratones Transgénicos
4.
Acad Psychiatry ; 38(4): 414-9, 2014 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-24570030

RESUMEN

OBJECTIVE: The aim of this study is to analyze qualitative data collected during field-testing of an instrument to assess psychiatric residents' experiences with systems-based practice (SBP). METHODS: A total of 237 psychiatry residents from 6 levels of training in 12 different psychiatry residency training programs responded to a 60-item instrument measuring their experiences with SBP during residency. Qualitative techniques adapted from content analysis were used to review narrative responses to open-ended questions on the instrument. RESULTS: Certain themes emerged in the residents' answers reflecting their opinions about the opportunities for (and barriers to) performing SBP in their work. CONCLUSIONS: Psychiatric residents express an eagerness for opportunities to learn about and perform SBP but often feel constrained by the lack of resources, teaching, and supervision. Moreover, many residents desire a better understanding of healthcare economics and how to factor cost consideration into clinical care.


Asunto(s)
Curriculum/normas , Internado y Residencia/normas , Práctica Profesional , Psiquiatría/educación , Adulto , Actitud del Personal de Salud , Femenino , Humanos , Masculino , Investigación Cualitativa
6.
Circ Res ; 108(10): 1199-208, 2011 May 13.
Artículo en Inglés | MEDLINE | ID: mdl-21474816

RESUMEN

RATIONALE: Fetuses that develop in diabetic mothers have a higher incidence of birth defects that include cardiovascular defects, but the signaling pathways that mediate these developmental effects are poorly understood. It is reasonable to hypothesize that diabetic maternal effects are mediated by 1 or more pathways activated downstream of aberrant glucose metabolism, because poorly controlled maternal glucose levels correlate with the frequency and severity of the defects. OBJECTIVE: We investigated whether RasGRP3 (Ras guanyl-releasing protein 3), a Ras activator expressed in developing blood vessels, mediates diabetes-induced vascular developmental defects. RasGRP3 is activated by diacylglycerol, and diacylglycerol is overproduced by aberrant glucose metabolism in diabetic individuals. We also investigated the effects of overactivation and loss of function for RasGRP3 in primary endothelial cells and developing vessels. METHODS AND RESULTS: Analysis of mouse embryos from diabetic mothers showed that diabetes-induced developmental defects were dramatically attenuated in embryos that lacked Rasgrp3 function. Endothelial cells that expressed activated RasGRP3 had elevated Ras-ERK signaling and perturbed migration, whereas endothelial cells that lacked Rasgrp3 function had attenuated Ras-ERK signaling and did not migrate in response to endothelin-1. Developing blood vessels exhibited endothelin-stimulated vessel dysmorphogenesis that required Rasgrp3 function. CONCLUSIONS: These findings provide the first evidence that RasGRP3 contributes to developmental defects found in embryos that develop in a diabetic environment. The results also elucidate RasGRP3-mediated signaling in endothelial cells and identify endothelin-1 as an upstream input and Ras/MEK/ERK as a downstream effector pathway. RasGRP3 may be a novel therapeutic target for the fetal complications of diabetes.


Asunto(s)
Movimiento Celular/genética , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Experimental/patología , Células Madre Embrionarias/metabolismo , Células Endoteliales/metabolismo , Complicaciones Cardiovasculares del Embarazo/metabolismo , Complicaciones Cardiovasculares del Embarazo/patología , Factores de Intercambio de Guanina Nucleótido ras/fisiología , Animales , Células Cultivadas , Diabetes Mellitus Experimental/genética , Técnicas de Cultivo de Embriones , Desarrollo Embrionario/genética , Células Madre Embrionarias/patología , Células Endoteliales/patología , Femenino , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Embarazo , Complicaciones Cardiovasculares del Embarazo/genética , Factores de Intercambio de Guanina Nucleótido ras/deficiencia , Factores de Intercambio de Guanina Nucleótido ras/genética
7.
Am J Psychiatry ; 167(3): 253-9, 2010 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-20194488

RESUMEN

Aggressive patients often target psychiatrists and psychiatric residents, yet most clinicians are insufficiently trained in violence risk assessment and management. Consequently, many clinicians are reluctant to diagnose and treat aggressive and assaultive features in psychiatric patients and instead focus attention on other axis I mental disorders with proven pharmacological treatment in the hope that this approach will reduce the aggressive behavior. Unclear or nonexistent reporting policies or feelings of self-blame may impede clinicians from reporting assaults, thus limiting our knowledge of the impact of, and best response to, aggression in psychiatric patients. The authors pre-sent the case of a young adult inpatient with a long history of antisocial and assaultive behavior who struck and injured a psychiatric resident. With this case in mind, the authors discuss the diagnostic complexities related to violent patients, the importance of assessing violence risk when initially evaluating a patient, and the relevance of risk assessment for treatment considerations and future management. This report illustrates common deficiencies in the prevention of violence on inpatient psychiatric units and in the reporting and response to an assault, and has implications for residency and clinician training.


Asunto(s)
Agresión/psicología , Trastorno de Personalidad Antisocial/psicología , Internado y Residencia , Psiquiatría/educación , Violencia/psicología , Adolescente , Trastorno de Personalidad Antisocial/diagnóstico , Trastorno de Personalidad Antisocial/terapia , Internamiento Obligatorio del Enfermo Mental , Comorbilidad , Conducta Peligrosa , Quimioterapia Combinada , Piromanía/psicología , Humanos , Masculino , Trastornos del Humor/diagnóstico , Trastornos del Humor/psicología , Trastornos del Humor/terapia , Prisioneros/psicología , Psicotrópicos/efectos adversos , Psicotrópicos/uso terapéutico , Medición de Riesgo , Gestión de Riesgos , Violencia/prevención & control
8.
Rejuvenation Res ; 10(3): 281-92, 2007 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-17665967

RESUMEN

Autophagy is a highly regulated intracellular process for the degradation of cellular constituents and essential for the maintenance of a healthy cell. We evaluated the effects of age and life-long calorie restriction on autophagy in heart and liver of young (6 months) and old (26 months) Fisher 344 rats. We observed that the occurrence of autophagic vacuoles was higher in heart than liver. The occurrence of autophagic vacuoles was not affected by age in either tissue, but was increased with calorie restriction in heart but not in liver. Next, we examined the expression of proteins involved in the formation and maturation of autophagosomes (beclin-1, LC3, Atg7, Atg9) or associated with autolysosomes and lysosomes (LAMP-1; cathepsin D). In hearts of both ad libitum-fed and calorie-restricted rats, we observed an increase in expression of beclin-1 and procathepsin D, but not mature cathepsin D, and a decrease in expression of LAMP-1 because of aging. In hearts, calorie restriction stimulated the expression of Atg7 and Atg9 and the lipidation of Atg8 (elevated LC3-II/I ratios) in aged rats. In hearts of ad libitum-fed rats, expression of Atg7 and lipidation of Atg8 were unaffected by age, while the cellular levels of Atg9 were lower in aged animals. Furthermore, we observed that the age- and diet-dependent expression levels of those proteins differed between heart and liver. In conclusion, autophagy in heart and liver did not decrease with age in ad libitum-fed rats, but was enhanced by calorie restriction in the heart. Thus, calorie restriction may mediate some of its beneficial effects by stimulating autophagy in the heart, indicating the potential for cardioprotective therapies.


Asunto(s)
Envejecimiento , Autofagia , Restricción Calórica , Corazón/fisiología , Hígado/fisiología , Animales , Proteínas Reguladoras de la Apoptosis/metabolismo , Beclina-1 , Catepsina D/metabolismo , Lípidos/química , Hígado/metabolismo , Masculino , Microscopía Electrónica de Transmisión , Miocardio/metabolismo , Miocitos Cardíacos/citología , Ratas , Ratas Endogámicas F344
9.
Oecologia ; 143(4): 645-51, 2005 May.
Artículo en Inglés | MEDLINE | ID: mdl-15800750

RESUMEN

Corridors connect otherwise isolated habitat patches and can direct movement of animals among such patches. In eight experimental landscapes, we tested two hypotheses of how corridors might affect dispersal behavior. The Traditional Corridor hypothesis posits that animals preferentially leave patches via corridors, following them into adjacent patches. The Drift Fence hypothesis posits that animals dispersing through matrix habitat are diverted into patches with corridors because they follow corridors when encountered. House flies (Musca domestica L.), a species that prefers the habitat of our patches and corridors, were released in a central patch (100x100 m) and recaptured in peripheral patches that were or were not connected by a corridor. Flies were captured more frequently in connected than unconnected patches, thereby supporting the Traditional Corridor hypothesis. The Drift Fence hypothesis was also supported, as flies were captured more frequently in unconnected patches with blind (dead end) corridors than in unconnected patches of equal area without blind corridors. A second experiment tested whether these results might be dependent on the type of patch-matrix boundary encountered by dispersing flies and whether edge-following behavior might be the mechanism underlying the observed corridor effect in the first experiment. We recorded dispersal patterns of flies released along forest edges with dense undergrowth in the forest ("closed" edges) and along edges with little forest understory ("open" edges). Flies were less likely to cross and more likely to follow closed edges than open edges, indicating that when patch and corridor edges are pronounced, edge-following behavior of flies may direct them along corridors into connected patches. Because edges in the first experiment were open, these results also suggest that corridor effects for flies in that experiment would have been even stronger if the edges around the source patches and corridors had been more closed. Taken together, our results suggest that corridors can affect dispersal of organisms in unappreciated ways (i.e., as drift fences) and that edge type can alter dispersal behavior.


Asunto(s)
Demografía , Ambiente , Moscas Domésticas/fisiología , Animales , Geografía , Modelos Lineales , Dinámica Poblacional , South Carolina
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