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1.
Front Nutr ; 10: 1278753, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38249601

RESUMEN

Introduction: Stunting and wasting are prevalent in low- and middle-income countries, putting children at risk for disease and disability. Eggs are a nutrient-rich food that can potentially facilitate growth. Purpose: The aim of this meta-analysis was to evaluate the potential beneficial effect of egg supplementation on growth in children. Methods: Following the PRISMA guidelines, PubMed and Healthline (Ovid) were systematically searched for interventional studies on egg supplementation for growth in children aged 6 months to 18 years, with no restrictions on date. Studies were evaluated for quality using Cochrane's GRADE technique. Data were pooled and reported as means and 95% confidence intervals. Results: Seven studies reporting on 9 unique interventions in 3,575 male and female participants were included in the meta-analysis. Participants in the intervention groups experienced significantly greater increases in height/length (by 0.47 [0.13, 0.80] cm, p < 0.01) and weight (by 0.07 [0.01, 0.13] kg, p = 0.03) when compared to those in the control groups. Conclusion: Eggs are an affordable, nutritious option for improving growth in children, though more studies with longer interventions are warranted.Systematic review registration: PROSPERO (CRD42021289609: https://www.crd.york.ac.uk/prospero/).

2.
Med Educ ; 56(8): 805-814, 2022 08.
Artículo en Inglés | MEDLINE | ID: mdl-35199378

RESUMEN

INTRODUCTION: During a health crisis, hospitals must prioritise activities and resources, which can compromise clerkship-based learning. We explored how health crises affect clinical clerkships using the COVID-19 pandemic as an example. METHODS: In a constructivist qualitative study, we conducted 22 semi-structured interviews with key stakeholders (i.e. medical students and doctors) from two teaching hospitals and 10 different departments. We used thematic analysis to investigate our data and used stakeholder theory as a sensitising concept. RESULTS: We identified three themes: (1) emotional triggers and reactions; (2) negotiation of legitimacy; and (3) building resilience. Our results suggest that the health crisis accentuated already existing problems in clerkships, such as students' feelings of low legitimacy, constant negotiation of roles, inconsistencies navigating rules and regulations and low levels of active participation. Medical students and doctors adapted to the new organisational demands by developing increased resilience. Students responded by reaching out for guidance and acceptance to remain relevant in the clinical clerkships. Doctors developed a behaviour of closing in and focused on managing themselves and their patients. This created tension between these two stakeholder groups. CONCLUSION: A health crisis can critically disrupt the hierarchical structure within the clinical clerkships and exacerbate existing conflicts between stakeholder groups. When medical students are not perceived as legitimate stakeholders in clinical clerkships during a health crisis, their attendance is perceived as unnecessary or even a nuisance. Despite increased student proactiveness and resilience, their roles inevitably shift from being doctors-to-be to students-to-be-managed.


Asunto(s)
COVID-19 , Prácticas Clínicas , Estudiantes de Medicina , COVID-19/epidemiología , Humanos , Pandemias , Investigación Cualitativa , Estudiantes de Medicina/psicología
3.
Mil Med ; 186(Suppl 3): 23-28, 2021 10 26.
Artículo en Inglés | MEDLINE | ID: mdl-34724050

RESUMEN

INTRODUCTION: The need to maintain medical ethical standards during conflict and peace has been the source of considerable academic discourse. Although still an unsolved challenge, scholars have made significant contributions to the literature, constructing categorizations that can help military providers contend with ethical conflicts. However, insights into the ethical comportment of military interprofessional healthcare teams (MIHTs) have yet to be reported. MATERIALS AND METHODS: This interview-based study collected insights from 30 military healthcare providers who participated in and/or led MIHTs. Altogether, participants represented 11 health professions, both officers and enlisted military members, and the U.S. Army, Navy, and Air Force. Following Grounded Theory methodology, data were collected and analyzed in iterative cycles until theme saturation was reached. RESULTS: The research team identified two themes of ethical bearing that enable MIHT success in and across care contexts. One theme of successful ethical bearing is "raising concerns," referring to speaking up when something needs to be addressed. The other is "making compromises," where individuals have to make sacrifices (e.g., lack of equipment, non-sterile environment, etc.) to give patient care. CONCLUSIONS: These data suggest that effective MIHTs have a collective moral compass. This moral compass is the team's ability to judge what is ethically right and wrong, as well as the team's willingness and ability to act accordingly-to consistently "do the right thing." There is a collective moral compass, and while the team may not all agree on what exactly is true north-they are all bending that way.


Asunto(s)
Personal Militar , Personal de Salud , Humanos , Principios Morales , Atención al Paciente , Grupo de Atención al Paciente
4.
Mil Med ; 186(Suppl 3): 16-22, 2021 10 26.
Artículo en Inglés | MEDLINE | ID: mdl-34724051

RESUMEN

INTRODUCTION: Interchangeability-i.e., the capacity to change places with another-is necessary for military interprofessional health care teams (MIHTs) to provide around-the-clock patient care. However, while interchangeability is clearly a necessity for modern health care delivery, it raises uncomfortable questions for civilian health care teams where it is usually labeled as unsafe. This perception surfaces because interchangeability runs counter to some of health care's cultural beliefs including those around patient ownership and professional scopes of practice. It is, therefore, not surprising that little is known about whether and how some level of interchangeability can be harnessed to improve the productivity of health care teams overall. In this article, we explore the notion of interchangeability in the particular context of MIHTs given that these health care teams are familiar with it. This exploration will offer insights into how interchangeability could maximize civilian health care teams' capacity to adapt. MATERIALS AND METHODS: We conducted a secondary analysis of interview data as an analytic expansion: "the kind of study in which the researcher makes further use of a primary data set in order to ask new or emerging questions that derive from having conducted the original analysis but were not envisioned within the original scope of the primary study aims". Within our secondary analysis approach, we used thematic analysis as our analytical tool to describe (1) what interchangeability looks like in MIHT teams, (2) how it is fostered in MIHTs, and (3) how it is enacted in MIHTs. RESULTS: Interchangeability was realized in MIHTs when individual team members adapted to take on roles and/or tasks that were not clearly niched in their specific areas of expertise but instead drew on the broad foundation of their clinical skill set. Cross-training and distributed leadership were ways in which MIHT members described how interchangeability was fostered. Furthermore, five features of working within MIHT teams were identified as key conditions to enact interchangeability: knowing your team members; being able to work with what/who you have; actively seeking others' expertise; situating your role within the broader picture of the mission; and maintaining a learning/teaching mindset. CONCLUSIONS: Interchangeability can be understood through the theoretical lens of Swarm Intelligence and more specifically, the principle of collective self-healing-which is the ability of collectives to continue to successfully perform despite disruption, challenges, or the loss of a team member. Our findings highlight how MIHTs have adopted interchangeability in a wide array of contexts to realize collective self-healing. Despite the discomfort it provokes, we suggest that interchangeability could be a powerful asset to civilian health care teams.


Asunto(s)
Personal Militar , Atención a la Salud , Humanos , Liderazgo , Atención al Paciente , Grupo de Atención al Paciente
5.
Mil Med ; 186(Suppl 3): 7-15, 2021 10 26.
Artículo en Inglés | MEDLINE | ID: mdl-34724052

RESUMEN

INTRODUCTION: The U.S. Military has long been aware of the vital role effective leaders play in high-functioning teams. Recently, attention has also been paid to the role of followers in team success. However, despite these investigations, the leader-follower dynamic in military interprofessional health care teams (MIHTs) has yet to be studied. Although interprofessional health care teams have become a topic of increasing importance in the civilian literature, investigations of MIHTs have yet to inform that body of work. To address this gap, our research team set out to study MIHTs, specifically focusing on the ways in which team leaders and followers collaborate in MIHTs. We asked what qualities of leadership and followership support MIHT collaboration? MATERIALS AND METHODS: This study was conducted using semi-structured interviews within a grounded theory methodology. Participants were purposefully sampled, representing military health care professionals who had experience working within or leading one or many MIHTs. Thirty interviews were conducted with participants representing a broad range of military health care providers and health care specialties (i.e., 11 different health professions), ranks (i.e., officers and enlisted military members), and branches of the U.S. Military (i.e., Army, Navy, and Air Force). Data were collected and analyzed in iterative cycles until thematic saturation was achieved. The subsets of data for leadership and followership were further analyzed separately, and the overlap and alignment across these two datasets were analyzed. RESULTS: The insights and themes developed for leadership and followership had significant overlap. Therefore, we present the study's key findings following the two central themes that participants expressed, and we include the perspectives from both leader and follower viewpoints to illustrate each premise. These themes are as follows: (1) a unique collaborative dynamic emerges when team members commit to a shared mission and a shared sense of responsibility to achieve that mission; and (2) embracing and encouraging both leader and follower roles can benefit MIHT collaboration. CONCLUSIONS: This study focused on ways in which team leaders and followers on MIHTs collaborate. Findings focused on qualities of leadership and followership that support MIHT's collaboration and found that MIHTs have a commitment to a shared mission and a shared sense of responsibility to achieve that mission. From this foundational position of collective responsibility to achieve a common goal, MIHTs develop ways of collaborating that enable leaders and followers to excel to include (1) understanding your role and the roles of others; (2) mutual respect; (3) flexibility; and (4) emotional safety. The study data suggest that MIHT members work along a continuum of leadership and followership, which may shift at any moment. Military interprofessional health care teams members are advised to be adaptive to these shared roles and contextual changes. We recommend that all members of MIHTs acquire leadership and followership training to enhance team performance.


Asunto(s)
Liderazgo , Personal Militar , Atención a la Salud , Personal de Salud , Humanos , Relaciones Interprofesionales , Grupo de Atención al Paciente
6.
Mil Med ; 186(Suppl 3): 42-47, 2021 10 26.
Artículo en Inglés | MEDLINE | ID: mdl-34724055

RESUMEN

INTRODUCTION: Multiple aspects of interpersonal dynamics can help or hinder the success of teams, particularly those in a Military Interprofessional Healthcare Team (MIHT). One specific mechanism for MIHTs' success is camaraderie and how these military teams are able to achieve, maintain, and enable the development of this important characteristic. Despite our understanding of military service members as being bonded like a family, we have a limited understanding of how this bond is translated into their MIHT experiences. MATERIALS AND METHODS: This study conducted interviews among 30 individuals who had participated in, led individual, and/or led many MIHTs, using a grounded theory methodology. Participants represented 11 different health professions, including officers and enlisted military members, and three branches of the U.S. military (e.g., army, navy, and air force). Data were collected and analyzed in iterative cycles until saturation was achieved. RESULTS: We identified six themes that shaped the overarching concept of camaraderie in MIHTs. These themes were (1) confidence in competent peers, (2) shared goals, (3) mutual respect, (4) desire to help one another improve, (5) personal is professional, and (6) bonds of military service. This paper describes each of these themes, provides illustrative examples from the data, and describes how these components contribute to MIHTs' team dynamics. We present a model for how to understand these themes. CONCLUSIONS: Through the identification and exploration of these aspects of camaraderie, we are able to better understand how MIHTs are able to be successful. MIHTs that demonstrated confidence in their brother/sister in arms possessed shared goals and missions, while maintaining mutual respect, a desire to help one another do better, and creating a personal and professional overlap tended to form stronger bonds of military service. Critically, these six aspects support a more nuanced understanding of the spirit of camaraderie and how it underpins MIHT success.


Asunto(s)
Personal Militar , Humanos , Masculino , Grupo de Atención al Paciente
7.
Mil Med ; 186(Suppl 3): 29-34, 2021 10 26.
Artículo en Inglés | MEDLINE | ID: mdl-34724056

RESUMEN

INTRODUCTION: Perseverance-doing something despite difficulty-is an asset to healthcare professionals, yet not all providers display this trait. The literature offers no conceptualization of perseverance as it relates to military caregivers. This research sought to explore the perseverance displayed by members of military interprofessional healthcare teams (MIHTs) and to construct a framework for explaining the role of perseverance in MIHTs' collaborative work. METHODS: Using Grounded Theory, this interview-based study collected insights from 30 individuals who had participated in MIHTs and/or led MIHTs. Participants represented 11 different health professions, both officers and enlisted military members, and three branches of the U.S. military (i.e., Army, Navy, and Air Force). Data were collected and analyzed in iterative cycles until theme saturation was achieved. RESULTS: We identified practices through which perseverance was exhibited by members of MIHTs: (1) humility, (2) mission focus, (3) team effort, (4) failure is not an option, (5) comfort with discomfort, and (6) continuous improvement. We then clustered these practices into three subcategories, reflecting how certain practices may connect to support MIHT perseverance. CONCLUSIONS: These six practices appear connected in significant ways to support the MIHTs' efforts. Humility, mission focus, and team effort can help team members collaborate as a unified and mutually supportive team. From this base, MIHTs seemed able to become comfortable with discomfort and to refuse failure as an option. These orientations then allowed the team to engage in continuous improvement. Together, these practices may enhance team perseverance and ultimately team performance.


Asunto(s)
Personal Militar , Atención a la Salud , Personal de Salud , Humanos , Relaciones Interprofesionales , Grupo de Atención al Paciente
8.
Mil Med ; 186(Suppl 3): 35-41, 2021 10 26.
Artículo en Inglés | MEDLINE | ID: mdl-34724057

RESUMEN

INTRODUCTION: Military healthcare providers working in military interprofessional healthcare teams (MIHTs) require situational awareness (SA) to ensure safe and efficacious patient care. This study aimed to explore SA in MIHTs to understand how SA can be reinforced and maintained in MIHTs. The research team set out to answer two questions: "What aspects of individual and team SA are particularly important for MIHTs?" and "How can we enable military healthcare providers to be effective MIHTs members with robust SA?". METHODS: This study used Grounded Theory methodology collecting perspectives from 30 study participants from various backgrounds, including 11 different healthcare professions from the U.S. Army, Air Force, and Navy. Each study participant had experiences participating in, leading one, or leading many MIHTs. Data were collected in three cycles and analyzed within each cycle until saturation was reached. RESULTS: Five themes were robustly represented in the data set regarding SA: (1) contextually informed adaptability, (2) readiness, (3) trust, (4) communication, and (5) mission focus. CONCLUSIONS: The urgency often faced by MIHTs brings SA and the principles that underpin SA into sharper focus. The SA themes identified in this research may provide insight into training effectiveness, team strengths and weaknesses, and team performance.


Asunto(s)
Concienciación , Personal Militar , Personal de Salud , Humanos , Atención al Paciente , Grupo de Atención al Paciente
9.
Mil Med ; 186(Suppl 3): 1-6, 2021 10 26.
Artículo en Inglés | MEDLINE | ID: mdl-34724058

RESUMEN

Military interprofessional healthcare teams (MIHTs) are foundational to the care provided to military members and their families. However, to date, very little research has investigated MIHTs. Notably, we have few insights into what distinguishes successful MIHTs. This manuscript presents findings from a program of research that was carried out to address this gap. We review what is known about MIHTs to date and the Uniformed Services University's (USU) focused efforts to ensure that greater understanding of MIHTs was developed. We provide an overview of the USU-supported research and of the findings that were generated by that inquiry. After summarizing the manuscripts included in this special edition of Military Medicine, we close by acknowledging and thanking key members of the U.S. military healthcare system who supported this research.


Asunto(s)
Medicina Militar , Personal Militar , Atención a la Salud , Humanos , Grupo de Atención al Paciente
10.
Mil Med ; 186(Suppl 3): 53-56, 2021 10 26.
Artículo en Inglés | MEDLINE | ID: mdl-34723321

RESUMEN

The success of the military is significantly supported by highly effective collaborative teams. While much is known about successful military teams outside the context of healthcare delivery, considerably less attention has been paid to teams working in patient care. Thus, this supplement has explored the features of successful military interprofessional healthcare teams (MIHTs). In this summary paper, the authors discuss what this supplement's investigations have taught us about MIHTs and offer a series of proposed future investigations of MIHTs and their role in military healthcare.


Asunto(s)
Personal Militar , Conducta Cooperativa , Atención a la Salud , Humanos , Relaciones Interprofesionales , Atención al Paciente , Grupo de Atención al Paciente
11.
Med Educ ; 55(6): 724-732, 2021 06.
Artículo en Inglés | MEDLINE | ID: mdl-33368489

RESUMEN

INTRODUCTION: Dyad learning occurs when two students work together to acquire new skills and knowledge. Several studies have provided evidence to support the educational rationale for dyad learning in the controlled simulated setting. However, the role of dyad learning in the clinical setting remains uncertain. Unlike the simulated setting, learning in the clinical setting depends on a complex interplay between medical students, doctors, nurses and patients potentially making dyad learning less valuable in clerkships. The objective of this study was to explore how key stakeholders perceive the value of implementing dyad learning during medical students' clinical clerkships. METHODS: In a constructivist qualitative study, we conducted 51 semi-structured interviews with 36 key stakeholders involved in dyad learning, including 10 medical students, 12 doctors, five nurses and nine patients. Data were coded inductively using thematic analysis, then coded deductively using stakeholder theory as a theoretical framework. RESULTS: We found that stakeholders generally perceived the educational impact of dyad learning in the clinical setting similarly but disagreed on its value. Students emphasised that dyad learning made them participate more actively during patient encounters and patients did not mind having two students present. Doctors and nurses considered dyad learning disruptive to the balance between service and training and reported that it did not resonate with their perception of good patient care. CONCLUSION: Dyad learning enables students to be more active during their clinical clerkships, but it easily disrupts the balance between service and training. This disruption may be exacerbated by the shifted balance in priorities and values between different stakeholder groups, as well as by making implicit teaching obligations more explicit for supervising doctors and nurses. Consequently, implementing dyad learning may not be perceived as valuable by doctors and nurses in the clinical setting, regardless of its pedagogical rationale.


Asunto(s)
Prácticas Clínicas , Educación de Pregrado en Medicina , Estudiantes de Medicina , Competencia Clínica , Humanos , Aprendizaje
13.
Mil Med ; 183(11-12): e448-e454, 2018 11 01.
Artículo en Inglés | MEDLINE | ID: mdl-29741728

RESUMEN

Introduction: Research into healthcare delivered via interprofessional healthcare teams (IHTs) has uncovered that IHTs can improve patient satisfaction, enhance collaborative behaviors, reduce clinical error rates, and streamline management of care delivery. Importantly, these achievements are attained by IHTs that have been trained via interprofessional education (IPE). Research indicates that IHT training must be contextualized to suit the demands of each care context. However, research into the unique demands required of military IHTs has yet to be explored. For any form of IPE to be successfully implemented in the military, we need a clear understanding of how IHT competencies must be tailored to suit military care contexts. Specifically, we must know: (1) What evidence is currently available regarding IHTs in the military?; and (2) What gaps in the evidence need to be addressed for IPE to be customized to meet the needs of military healthcare delivery? Method: A scoping review of the literature was conducted to identify the breadth of knowledge currently available regarding military interprofessional healthcare teams (MIHTs). A search of PubMed, EMBASE, PsycInfo, ERIC, DTIC.mil, and NYAM Gray Literature databases was conducted without date restrictions. The search terms were: (interprofessional* OR inter-professional*) AND (military OR Army OR Navy OR Naval OR Marines OR "Air Force" OR "Public Health Service") AND (health OR medicine). Of the 675 articles identified via the initial search, only 21 articles met inclusion criteria (i.e., involved military personnel, included teams that were medically focused, comprised at least two professional disciplines, and had at least two people). Results: The manuscripts included: seven original research studies, six commentaries, five reviews, one letter, one annual report, and one innovation report. Analyses identified three themes (i.e., effective communication, supportive team environments, shared role understanding, and equity among team members) related to successful MIHT collaborations and five related to unsuccessful MIHT collaborations (i.e., inability to develop team cohesion, lack of trust, ineffective communication and communication breakdowns, unaddressed or unresolved conflicts, and rank conflicts). These manuscripts highlighted contextual factors that shape MIHTs. For example, MIHTs often work and live together for extended periods of time when deployed. Also, military rank can facilitate collaboration by establishing clear lines of reporting but can problematize collaboration when inexperienced care providers (e.g., early career physicians) outrank other team members (e.g., medics) who have more experience providing care in deployment contexts. Discussion: Given that the experiences of military personnel can be perilous and unpredictable, the military has an obligation to study the unique contexts of care where MIHTs are employed. In doing so, educational interventions can be tailored to better aid our service men and women, as well as their families.


Asunto(s)
Relaciones Interprofesionales , Personal Militar/psicología , Grupo de Atención al Paciente/normas , Competencia Clínica/normas , Conducta Cooperativa , Personal de Salud/psicología , Humanos , Grupo de Atención al Paciente/tendencias
14.
Science ; 344(6179): 90-3, 2014 Apr 04.
Artículo en Inglés | MEDLINE | ID: mdl-24700858

RESUMEN

Redesigning lignin, the aromatic polymer fortifying plant cell walls, to be more amenable to chemical depolymerization can lower the energy required for industrial processing. We have engineered poplar trees to introduce ester linkages into the lignin polymer backbone by augmenting the monomer pool with monolignol ferulate conjugates. Herein, we describe the isolation of a transferase gene capable of forming these conjugates and its xylem-specific introduction into poplar. Enzyme kinetics, in planta expression, lignin structural analysis, and improved cell wall digestibility after mild alkaline pretreatment demonstrate that these trees produce the monolignol ferulate conjugates, export them to the wall, and use them during lignification. Tailoring plants to use such conjugates during cell wall biosynthesis is a promising way to produce plants that are designed for deconstruction.


Asunto(s)
Aciltransferasas/química , Aciltransferasas/genética , Lignina/química , Lignina/metabolismo , Populus/genética , Populus/metabolismo , Aciltransferasas/aislamiento & purificación , Angelica sinensis/enzimología , Angelica sinensis/genética , Pared Celular/química , Pared Celular/metabolismo , Ácidos Cumáricos/metabolismo , Genes de Plantas , Estructura Molecular , Raíces de Plantas/enzimología , Plantas Modificadas Genéticamente/genética , Plantas Modificadas Genéticamente/crecimiento & desarrollo , Populus/crecimiento & desarrollo , Árboles/genética , Árboles/metabolismo
15.
Phys Rev Lett ; 104(20): 200501, 2010 May 21.
Artículo en Inglés | MEDLINE | ID: mdl-20867015

RESUMEN

Molecular nanostructures may constitute the fabric of future quantum technologies, if their degrees of freedom can be fully harnessed. Ideally one might use nuclear spins as low-decoherence qubits and optical excitations for fast controllable interactions. Here, we present a method for entangling two nuclear spins through their mutual coupling to a transient optically excited electron spin, and investigate its feasibility through density-functional theory and experiments on a test molecule. From our calculations we identify the specific molecular properties that permit high entangling power gates under simple optical and microwave pulses; synthesis of such molecules is possible with established techniques.

16.
Cell Mol Life Sci ; 66(4): 681-96, 2009 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-19137261

RESUMEN

hShroom1 (hShrm1) is a member of the Apx/Shroom (Shrm) protein family and was identified from a yeast two-hybrid screen as a protein that interacts with the cytoplasmic domain of melanoma cell adhesion molecule (MCAM). The characteristic signature of the Shrm family is the presence of a unique domain, ASD2 (Apx/Shroom domain 2). mRNA analysis suggests that hShrm1 is expressed in brain, heart, skeletal muscle, colon, small intestine, kidney, placenta and lung tissue, as well a variety of melanoma and other cell lines. Co-immunoprecipitation and bioluminescence resonance energy transfer (BRET) experiments indicate that hShrm1 and MCAM interact in vivo and by immunofluorescence microscopy some co-localization of these proteins is observed. hShrm1 partly co-localises with beta-actin and is found in the Triton X-100 insoluble fraction of melanoma cell extracts. We propose that hShrm1 is involved in linking MCAM to the cytoskeleton.


Asunto(s)
Actinas/metabolismo , Citoesqueleto/metabolismo , Proteínas de la Membrana/metabolismo , Proteínas de Microfilamentos/metabolismo , Isoformas de Proteínas/metabolismo , Empalme Alternativo , Secuencia de Aminoácidos , Animales , Antígeno CD146/genética , Antígeno CD146/metabolismo , Línea Celular , Humanos , Melanoma/genética , Melanoma/metabolismo , Proteínas de la Membrana/genética , Proteínas de Microfilamentos/genética , Datos de Secuencia Molecular , Isoformas de Proteínas/genética , Proteínas Recombinantes de Fusión/genética , Proteínas Recombinantes de Fusión/metabolismo , Técnicas del Sistema de Dos Híbridos
17.
Neuroscience ; 142(3): 843-58, 2006 Oct 27.
Artículo en Inglés | MEDLINE | ID: mdl-16934941

RESUMEN

Studies in congenitally blind and bilaterally enucleated individuals show that an early loss of sensory driven activity can lead to massive functional reorganization. However, the anatomical substrate for this functional reorganization is unknown. In the present study, we examined patterns of corticocortical and thalamocortical connections in adult opossums that had been bilaterally enucleated neonatally, prior to the formation of retinogeniculate and geniculocortical connections. We show that in addition to normal thalamocortical projection patterns from visual nuclei, enucleated animals also receive input from nuclei associated with the somatosensory (ventral posterior nucleus, VP), auditory (medial geniculate nucleus, MGN), motor (ventrolateral nucleus, VL), and limbic/hippocampal systems (anterior dorsal nucleus, AD; and anterior ventral nucleus, AV). Likewise, in addition to normal corticocortical projections to area 17, bilaterally enucleated opossums also receive input from auditory, somatosensory, and multimodal cortex. These aberrant patterns of thalamocortical and corticocortical connections can account for alterations in functional organization observed in the visual cortex of bilateral enucleated animals, and indicate that factors extrinsic to the cortex play a large role in cortical field development and evolution. On the other hand, the maintenance of normal patterns of connections in the absence of visual input suggests that there are formidable constraints imposed on the developing cortex that highly restrict the types of evolutionary change possible.


Asunto(s)
Ceguera/patología , Tálamo/patología , Corteza Visual/patología , Vías Visuales/patología , Factores de Edad , Animales , Animales Recién Nacidos , Mapeo Encefálico , Modelos Animales de Enfermedad , Electrofisiología/métodos , Enucleación del Ojo/métodos , Femenino , Lateralidad Funcional , Masculino , Modelos Neurológicos , Tálamo/crecimiento & desarrollo , Corteza Visual/crecimiento & desarrollo , Corteza Visual/fisiopatología , Vías Visuales/crecimiento & desarrollo
19.
J Allergy Clin Immunol ; 106(5): 941-7, 2000 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-11080718

RESUMEN

BACKGROUND: Previous reports indicate that IL-12 may be involved in the development of chronic atopic dermatitis. However, the cellular source of this cytokine in the skin and its expression during successful treatment of the skin lesions are not known. OBJECTIVE: Our purpose was to delineate the precise in situ localization of IL-12 and its modulation under topical treatment with corticosteroids. METHODS: Skin biopsy specimens were obtained from nonlesional, lesional, and treated skin of patients with atopic dermatitis and from healthy skin of nonatopic control subjects. IL-12 was investigated by real-time quantitative reverse transcriptase-PCR and immunohistochemistry. RESULTS: Expression of IL-12 p40 mRNA was significantly enhanced in lesional skin from atopic dermatitis and strongly down-regulated after treatment with topical corticosteroids for 9 to 10 days. In contrast, similar levels of IL-12 p35 transcripts were found in all the samples without any significant differences after treatment. In addition, a strong enhancement of IL-12 immunoreactivity was observed on the mononuclear cell infiltrate in the lesional skin samples, which was also markedly reduced after treatment. IL-12 immunoreactivity was mainly located in the cytoplasm of dermal dendritic cells and macrophages as well as some Langerhans cells. CONCLUSION: Our data suggest that the enhanced local production of IL-12 in dendritic cells and macrophages may be responsible for up-regulating production of IFN-gamma in chronic lesions and strengthen the idea that IL-12 may have a pivotal role in promoting inflammation in atopic dermatitis.


Asunto(s)
Corticoesteroides/uso terapéutico , Antiinflamatorios/uso terapéutico , Dermatitis Atópica/inmunología , Regulación hacia Abajo/efectos de los fármacos , Interleucina-12/genética , Administración Tópica , Adolescente , Adulto , Animales , Línea Celular Transformada , Enfermedad Crónica , Células Dendríticas/inmunología , Dermatitis Atópica/tratamiento farmacológico , Dermatitis Atópica/patología , Femenino , Glucocorticoides , Humanos , Técnicas para Inmunoenzimas , Macrófagos/inmunología , Masculino , Persona de Mediana Edad , ARN Mensajero , Conejos , Piel/inmunología , Piel/patología
20.
J Invest Dermatol ; 115(4): 668-73, 2000 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-10998141

RESUMEN

The melanoma cell adhesion molecule is a membrane glycoprotein whose expression is associated with tumor progression and the development of metastatic potential. The mechanisms for upregulation of the melanoma cell adhesion molecule during melanoma progression are still poorly understood. In this study, we show further evidence that melanoma cell adhesion molecule expression is tightly regulated at the transcriptional level. Using a combination of chloramphenicol acetyl transferase reporter assays and DNA mobility shift experiments, we investigated the role played by three putative melanoma cell adhesion molecule regulatory elements, namely the initiator sequence, the SCA element, and the ASp element. The SCA and the ASp boxes can potentially interact with the transcription factors Sp1 and AP-2. Sp1 binding to both sites was confirmed, but only the SCA sequence could form a complex with AP-2. AP-2-driven downregulation of the melanoma cell adhesion molecule promoter, however, did not depend only on a functional SCA element. The pyrimidine-rich CTCACTTG initiator, which overlaps the RNA start site, was essential for promoter function and was shown to interact with proteins related to basic helix-loop-helix transcription factors. Binding in nonmetastatic melanoma cells was induced by cAMP. In metastatic cells, however, binding was constitutive, but could be markedly decreased upon treatment with phorbol esters. As melanoma cell adhesion molecule expression is modulated by cAMP and phorbol ester signaling, these results suggest that the initiator is the central element that mediates cAMP and phorbol ester sensitivity and initiates melanoma cell adhesion molecule overexpression in melanomas.


Asunto(s)
Antígenos CD , Antígenos de Superficie/genética , Codón Iniciador/fisiología , Glicoproteínas de Membrana , Moléculas de Adhesión de Célula Nerviosa , Animales , Antígeno CD146 , Proteínas de Unión al ADN/fisiología , Regulación hacia Abajo , Regulación de la Expresión Génica , Ratones , Regiones Promotoras Genéticas/fisiología , Neoplasias Cutáneas/química , Neoplasias Cutáneas/genética , Factores de Transcripción/fisiología , Transcripción Genética/efectos de los fármacos
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