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INTRODUCTION: Developmental windows in which experiences can elicit long-lasting effects on brain circuitry and behavior are called "sensitive periods" and reflect a state of heightened plasticity. The classic example of a sensitive period comes from studies of sensory systems, like the visual system, where early visual experience is required for normal wiring of primary visual cortex and proper visual functioning. At a mechanistic level, loss of incoming visual input results in a decrease in activity in thalamocortical neurons representing the affected eye, resulting in an activity-dependent reduction in the representation of those inputs in the visual cortex and loss of visual perception in that eye. While associative cortical regions like the medial prefrontal cortex (mPFC) do not receive direct sensory input, recent findings demonstrate that changes in activity levels experienced by this region during defined windows in early development may also result in long-lasting changes in prefrontal cortical circuitry, network function, and behavior. For example, we recently demonstrated that decreasing the activity of mPFC parvalbumin-expressing (PV) interneurons during a period of time encompassing peripuberty (postnatal day P14) to adolescence (P50) led to a long-lasting decrease in their functional inhibition of pyramidal cells, as well as impairments in cognitive flexibility. While the effects of manipulating mPFC PV interneuron activity were selective to development, and not adulthood, the exact timing of the sensitive period for this manipulation remains unknown. METHODS: To refine the sensitive period in which inhibiting mPFC PV cell activity can lead to persistent effects on prefrontal functioning, we used a chemogenetic approach to restrict our inhibition of mPFC PV activity to two distinct windows: (1) peripuberty (P14-P32) and (2) early adolescence (P33-P50). We then investigated adult behavior after P90. In parallel, we performed histological analysis of molecular markers associated with sensitive period onset and offset in visual cortex, to define the onset and offset of peak-sensitive period plasticity in the mPFC. RESULTS: We found that inhibition of mPFC PV interneurons in peripuberty (P14-P32), but not adolescence (P33-P50), led to an impairment in set-shifting behavior in adulthood manifest as an increase in trials to reach criterion performance and errors. Consistent with a pubertal onset of sensitive period plasticity in the PFC, we found that histological markers of sensitive period onset and offset also demarcated P14 and P35, respectively. The time course of expression of these markers was similar in visual cortex. CONCLUSION: Both lines of research converge on the peripubertal period (P14-P32) as one of heightened sensitive period plasticity in the mPFC. Further, our direct comparison of markers of sensitive period plasticity across the prefrontal and visual cortex suggests a similar time course of expression, challenging the notion that sensitive periods occur hierarchically. Together, these findings extend our knowledge about the nature and timing of sensitive period plasticity in the developing mPFC.
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There are two dominant approaches to implementing permanent supportive housing (PSH), namely place-based (PB) and scattered-site (SS). Formal guidance does not distinguish between these two models and only specifies that PSH should be reserved for those who are most vulnerable with complex health needs. To consider both system- and self-selection factors that may affect housing assignment, this study applied the Gelberg-Anderson behavioral model for vulnerable populations to compare predisposing, enabling, and need factors among people experiencing homelessness (PE) by whether they were assigned to PB-PSH (n = 272) or SS-PSH (n = 185) in Los Angeles County during the COVID-19 pandemic. This exploratory, observational study also included those who were approved but did not receive PSH (n = 94). Results show that there are notable differences between (a) those who received PSH versus those who did not, and (b) those in PB-PSH versus SS-PSH. Specifically, PEH who received PSH were more likely to be white, US-born, have any physical health condition, and have lower health activation scores. PEH who received PB- versus SS-PSH were more likely to be older, Black, have any alcohol use disorder, and have higher health activation scores. These findings suggest that homeless service systems may consider PB-PSH more appropriate for PEH with higher needs but also raises important questions about how race may be a factor in the type of PSH that PEH receive and whether PSH is received at all.
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Background: The absence of the left atrial appendage is an exceedingly rare structural variant that could have important implications for anticoagulation regimens in patients with atrial fibrillation. Case summary: We report the case of a 63-year-old Puerto Rican female with a history of hypertension, cerebral artery aneurysms, and type 2 diabetes mellitus who suffered multiple haemorrhagic strokes. The patient had never received anticoagulation therapy. During the indicated stroke work-up, the patient was found to have paroxysmal atrial fibrillation. Given the patients high risk for thromboembolism and contraindications to anticoagulation therapy, the patient was referred for left atrial appendage occlusion. Pre-procedural transoesophageal echocardiography failed to identify the left atrial appendage. Evaluation by way of cardiac computed tomography confirmed absence of the left atrial appendage. Left atrial appendage occlusion could not be carried out. The patient had been deemed being at high risk of bleeding, was not anticoagulated, and was instead closely followed. The patient has not had thrombo-embolic events nor has she experienced a haemorrhagic stroke recurrence at follow-up appointments. Discussion: To our knowledge, this is the first such case report that reports left atrial appendage absence in the setting of multiple haemorrhagic strokes. Given the rarity of the condition and lack of available guidelines, the most viable way to currently manage this patient population is on a case-to-case basis. However, we propose that absence of the left atrial appendage could confer a decreased risk of thrombo-embolic phenomena in patients with atrial fibrillation.
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It is expected that CO2 concentration will increase in the air, thereby stimulating the photosynthesis process and, hence, plant biomass production. In the case of legumes, increased biomass due to higher CO2 concentration can stimulate atmospheric nitrogen (N2) fixation in the nodules. However, N2 fixation is inhibited by external N supply. Thus, biomass production and N2 fixation were analysed in two legumes (Pisum sativum L. and Vicia faba L.) grown at two levels of CO2 and three N levels. P. sativum reduces fixation with high soil N (facultative), while V. faba maintains high fixation regardless of soil N levels (obligate). The N2 fixation and plant and nodule biomass of the two species were evaluated in a pot experiment under controlled conditions using growth chambers with artificial CO2 supply and N addition. The proportion of N derived from the air (%Ndfa) present in the plants' biomass was calculated from the natural abundance of 15N and the N concentration of plant tissues using nonlegumes reference plants. Additionally, N content data are presented for both species growing at two levels of air CO2. The data may be useful for plant physiologists, especially those working on biological N2 fixation with non-model legumes at elevated CO2.
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Intercropping legumes with cereals can lead to increased overall yield and optimize the utilization of resources such as water and nutrients, thus enhancing agricultural efficiency. Legumes possess the unique ability to acquire nitrogen (N) through both N2 fixation and from the available N in the soil. However, soil N can diminish the N2 fixation capacity of legumes. It is postulated that in intercropping, legumes uptake N mainly through N2 fixation, leaving more soil N available for cereals. The latter, in turn, has larger root systems, allowing it to explore greater soil volume and absorb more N, mitigating its adverse effects on N2 fixation in legumes. The goal of this study was to evaluate how the supply of N affects the intercropping of faba beans (Vicia faba L.) and peas (Pisum sativum L.) with wheat under varying plant densities and N levels. We measured photosynthetic traits, biomass production, the proportion of N derived from air (%Ndfa) in the shoot of the legumes, the N transferred to the wheat, and the land equivalent ratio (LER). The results revealed a positive correlation between soil N levels and the CO2 assimilation rate (An), chlorophyll content, and N balance index (NBI) in wheat. However, no significant effect was observed in legumes as soil N levels increased. Transpiration (E) increased in wheat intercropped with legumes, while stomatal conductance (gs) increased with N addition in all crops. Water use efficiency (WUE) decreased in faba beans intercropped with wheat as N increased, but it showed no significant change in wheat or peas. The shoot dry matter of wheat increased with the addition of N; however, the two legume species showed no significant changes. N addition reduced the %Ndfa of both legume species, especially in monoculture, with peas being more sensitive than faba beans. The intercropping of wheat alleviated N2 fixation inhibition, especially at high wheat density and increased N transfer to wheat, particularly with peas. The LER was higher in the intercropping treatments, especially under limited N conditions. It is concluded that in the intercropping of wheat with legumes, the N2 fixation inhibition caused by soil N is effectively reduced, as well as there being a significant N transfer from the legume to the wheat, with both process contributing to increase LER.
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BACKGROUND: Traumatic brain injury (TBI) is a debilitating neurological disorder caused by an impact to the head by an outside force. TBI results in persistent cognitive impairments, including fear generalization and the inability to distinguish between aversive and neutral stimuli. The mechanisms underlying fear generalization have not been fully elucidated, and there are no targeted therapeutics to alleviate this symptom of TBI. METHODS: To identify the neural ensembles mediating fear generalization, we utilized ArcCreERT2 × enhanced yellow fluorescent protein (EYFP) mice, which allow for activity-dependent labeling and quantification of memory traces. Mice were administered a sham surgery or the controlled cortical impact model of TBI. Mice were then administered a contextual fear discrimination paradigm and memory traces were quantified in numerous brain regions. In a separate group of mice, we tested if (R,S)-ketamine could decrease fear generalization and alter the corresponding memory traces in TBI mice. RESULTS: TBI mice exhibited increased fear generalization when compared with sham mice. This behavioral phenotype was paralleled by altered memory traces in the dentate gyrus, CA3, and amygdala, but not by alterations in inflammation or sleep. In TBI mice, (R,S)-ketamine facilitated fear discrimination, and this behavioral improvement was reflected in dentate gyrus memory trace activity. CONCLUSIONS: These data show that TBI induces fear generalization by altering fear memory traces and that this deficit can be improved with a single injection of (R,S)-ketamine. This work enhances our understanding of the neural basis of TBI-induced fear generalization and reveals potential therapeutic avenues for alleviating this symptom.
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Lesiones Traumáticas del Encéfalo , Ketamina , Ratones , Animales , Ketamina/farmacología , Hipocampo/metabolismo , Lesiones Traumáticas del Encéfalo/tratamiento farmacológico , Lesiones Traumáticas del Encéfalo/metabolismo , Miedo , Encéfalo , Ratones Endogámicos C57BLRESUMEN
BACKGROUND: Alcohol and tobacco are important risk factors for chronic pancreatitis (CP). AIM: To analyze the effect of etiological factors such as tobacco and alcohol and pancreatic enzyme replacement therapy (PERT) in the progression of CP. MATERIAL AND METHODS: Patients with a diagnosis of CP were recruited and grouped according to variables such as tobacco, alcohol and PERT. They were followed for 18 months. Subsequently, different variables and analytical parameters involved in the progression of the disease were analyzed. RESULTS: A total of 50 patients diagnosed with CP were included. Of these, 28 patients underwent PERT, 39 were smokers and 33 were alcohol users. Compared with patients without PERT, those with PERT had a higher proportion of diabetes (64 and 32%, respectively), had a higher need for endoscopic treatment (25 and 0%, respectively) and a normal body mass index (71 and 27.3%, respectively. The smokers had higher calcium levels and increased lymphocytosis and leukocytosis. The alcohol consumption group had a higher mean age (p = 0.04) CONCLUSIONS: PERT may improve the nutritional status but does not reduce the need for endoscopic or surgical treatment. Smoking and alcohol consumption favored the progression of CP. Also, smoking induced a pro-inflammatory state.
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Humanos , Masculino , Femenino , Adulto , Persona de Mediana Edad , Anciano , Pancreatitis Crónica/etiología , Pancreatitis Crónica/terapia , Pancreatitis Crónica/epidemiología , Páncreas , Insuficiencia Pancreática Exocrina/etiología , Insuficiencia Pancreática Exocrina/terapia , Nicotiana/efectos adversos , Consumo de Bebidas Alcohólicas/efectos adversos , Factores de Riesgo , Distribución por Sexo , Progresión de la Enfermedad , Terapia EnzimáticaRESUMEN
RESUMEN La lesión pulmonar aguda producida por transfusión (TRALI, por sus siglas en inglés) es un síndrome clínico relativamente raro, que puede constituir una amenaza para la vida y que se caracteriza por insuficiencia respiratoria aguda, edema pulmonar no cardiogénico e hipotensión arterial durante o en el transcurso de 6 horas después de una transfusión de productos hemáticos. Aunque su verdadera incidencia es desconocida, se le ha atribuido 1 caso por cada 5000 transfusiones de cualquier producto hemático y ha sido una de las causas más frecuentes de muerte relacionada con la transfusión. Se presenta un caso de TRALI en el perioperatorio de una cirugía cardíaca con manifestaciones clínicas extremas, cuyo abordaje terapéutico fue extremadamente difícil para el equipo médico-quirúrgico, debido al contexto clínico en el que se presentó: cirugía cardíaca con circulación extracorpórea por diagnóstico de endocarditis infecciosa, lesión pulmonar previa y antecedente de otro tipo de reacción postransfusional.
ABSTRACT Transfusion-Related Acute Lung Injury (TRALI) is a relatively unusual, life-threatening clinical syndrome, characterized by acute respiratory failure, hypotension, and non-cardiogenic pulmonary edema during or within 6 hours after a blood product transfusion. Although its true incidence is unknown, it has been attributed one case per 5.000 transfusions of any blood product and has been one of the most frequent causes of transfusion-related death. We present a case of TRALI in the perioperative period of cardiac surgery with extreme clinical manifestations, whose therapeutic approach was extremely difficult for the medical-surgical team, due to its complex clinical setting: cardiac surgery with cardiopulmonary bypass due to diagnosis of infective endocarditis, previous lung injury and history of other post-transfusion reaction.
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Respiración , Lesión Pulmonar Aguda , Lesión Pulmonar Aguda PostransfusionalRESUMEN
Objetivos: El presente estudio se plantea describir la efectividad de los programas psicoeducativos en la disminución de la sobrecarga y la sintomatología derivada de la misma en cuidadores principales de familiares con enfermedad de Alzheimer. Metodología: Se ha llevado a cabo un proceso de revisión bibliográfica en diferentes bases de datos electrónicas nacionales (IME, CUIDEN) e internacionales (CINAHL, COCHRANE y MEDLINE), que se ha completado con una búsqueda manual en editoriales electrónicas, guías de práctica clínica y motores de búsqueda y con una búsqueda secundaria de artículos. Se han admitido publicaciones realizadas entre enero de 2000 y febrero de 2014. Resultados: La bibliografía consultada ofrece resultados poco claros. Aunque existe un número importante de estudios en los que las intervenciones psicoeducativas han mostrado resultados positivos, en muchos de los casos no se obtienen los efectos esperados. Conclusiones: Se considera necesario profundizar en el desarrollo de nuevos programas psicoeducativos, superando las limitaciones metodológicas encontradas (AU)
Objectives: The present study considers describing the effectiveness of psychoeducational programs in the reduction of the overburden and the symptomatology derived from it in primary caregivers of relatives with Alzheimers disease. Methodology: A bibliographic review process has been carried out in different national (IME, CUIDEN) and international (CINAHL, COCHRANE and MEDLINE) electronic databases, completing it with a manual search in electronic editorials, clinical practice guides and search engines, and with a secondary search of articles. Publications published between January 2000 and February 2014 have been accepted. Results: The consulted literature offers unclear results; although there are a number of studies in which psychoeducational interventions have shown positive results, in many cases the expected effects are not obtained. Conclusions: It is considered necessary to delve into the development of new psychoeducational programs, overcoming the methodological limitations that have been encountered (AU)
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Humanos , Enfermedad de Alzheimer/epidemiología , Cuidadores/educación , Atención Domiciliaria de Salud/educación , Cuidadores/psicología , Evaluación Educacional , Estrés Psicológico/epidemiologíaRESUMEN
Objetivo: Describir un brote epidémico de enfermedad gastrointestinal en un grupo de 56 pacientes de Medellín, Colombia. Metodología En abril de 2002 se presentó un número inusitado de casos de diarrea y a partir del hallazgo de Cyclospora cayetanensis en uno de los pacientes, se recolectaron 56 muestras de materia fecal de igual número de individuos. Se realizó una encuesta clínico-epidemiológica, coprológico directo, concentración con formol-éter y coloración de Zielh Neelsen modificada. Además, se estudiaron por directo y Zielh Neelsen muestras de algunos alimentos para la búsqueda del parásito. Resultados Del total de pacientes evaluados, 55,4 por ciento (31/56) fueron positivos para C. cayetanensis, de éstos, el 77,4 por ciento (24/31) fueron mujeres, y el 83,9 por ciento (26/31) pertenecía a la Universidad de Antioquia, de los cuales el 88,6 por ciento eran empleados no docentes. No se encontraron diferencias significativas entre pacientes positivos y negativos para Cyclospora con respecto a las manifestaciones clínicas, excepto en la deshidratación que fue mayor en los pacientes con ciclosporidiasis. Sin embargo, se encontró una diferencia significativa con relación al consumo de ensaladas y jugos, la cual fue mayor entre los pacientes positivos que los negativos. Conclusión Se presentó un brote epidémico de C. cayetanensis en pacientes sintomáticos atendidos por el grupo GIEPI en abril de 2002.
Objective: Describing an outbreak of gastrointestinal disease in a group of 56 patients from Medellín, Colombia. Methods An unusual number of cases of diarrhoea appeared in April 2002 and 56 samples of stool from the same number of individuals were collected because a patient proved Cyclospora cayetanensis positive. A clinical-epidemiological survey, direct coprology, formol-ether concentration and modified Zielhs Neelsen staining were then carried out. Some food samples were also studied for parasites by direct and modified Zielh Neelsen staining. Results 55,4 percent (31/56) of the patients being evaluated proved positive for C. cayetanensis. 77,4 percent (24/31) were women and 83,9 percent (26/31) belonged to the University of Antioquia, 88,6 percent of whom were not teachers. There was no statistically significant difference between positive and negative patients for Cyclospora regarding clinical manifestations, except for dehydration which was greater in patients having cyclosporiasis. However, there was a significant difference regarding consuming salads and juice, this being greater amongst positive patients than negative ones. Conclusion An outbreak of C. cayetanensis appeared in symptomatic patients being taken care of by the GIEPI group during April 2002.
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Adolescente , Adulto , Animales , Niño , Preescolar , Femenino , Humanos , Lactante , Recién Nacido , Masculino , Persona de Mediana Edad , Cyclospora , Ciclosporiasis/epidemiología , Brotes de Enfermedades , Factores de Edad , Colombia/epidemiología , Cyclospora/aislamiento & purificación , Ciclosporiasis/diagnóstico , Interpretación Estadística de Datos , Deshidratación/etiología , Factores SexualesRESUMEN
El absceso hepático amibiano (AHA) es la complicación extraintestinal más frecuente de la amibiasis; su cuadro clínico es generalmente agudo y se lo considera una urgencia médica. Se manifiesta con síntomas generales, acompañado de dolor en hipocondrio derecho, que se puede irradiar al hombro; la hepatomegalia dolorosa es un signo sugestivo pero no diagnóstico; debe diferenciarse del absceso hepático piógeno y del hepatoma necrótico; para el enfoque diagnóstico se requieren ayudas imaginológicas y pruebas de laboratorio como las inmunológicas. En este estudio se puso a punto la prueba de ELISA para la determinación de anticuerpos antiamibianos en sueros controles de pacientes con AHA, estandarizada en el Instituto Nacional de Salud de Bogotá. Además se evaluaron 67 muestras de pacientes con sospecha clínica de AHA, procedentes del Hospital González Valencia de Bucaramanga y del Hospital Universitario San Vicente de Paúl de Medellín. El 70.2 por ciento de los sueros problema evaluados fueron positivos, con una tasa de positividad significativamente mayor en los procedentes de Bucaramanga.