The effects of enriched environment on BDNF expression in the mouse cerebellum depending on the length of exposure.

Environmental enrichment (EE) has been proposed as a factor that improves neuronal connectivity and brain plasticity. The induction of molecular mechanisms that takes place in the cortex, nucleus accumbens and hippocampus resulting from exposure to EE has been attributed partly to the role of neurotrophins as brain-derived neurotrophic factor (BDNF). Recent data directly implicate this neurotrophin in the modulation of plasticity changes in the cerebellum produced by living under environmental enrichment. In the present study, we aimed to assess the effects of different lengths of exposure to EE on cerebellar BDNF expression and western blotting analysis. On the whole, the present data has shown that BDNF increased under EE. However, changes in expression as a result of extending the duration of EE were only seen in Purkinje neurons. In Purkinje neurons, long-term exposure was required in order to fully express this neurotrophin. These data support BDNF as one of the long-term plasticity mechanisms induced by environment, suggesting that cerebellar plasticity can be stimulated as a response to challenges generated by environment. Our findings could have functional implications for various neurodegenerative disorders such as spinocerebellar ataxias, autism, schizophrenia and certain prion encephalopathies, most of them pathologies which have demonstrated to be characterized by alterations in Purkinje neurons and to show a partial recovery by exposure to EE.

[A transesophageal color-coded pulsed Doppler echocardiographic study of the spatial distribution of mitral regurgitation jets]. / Estudo ecocardiográfico Doppler pulsado codificado a cor transesofágico da distribuição espacial dos jactos de regurgitação valvular mitral.

OBJECTIVE: Transesophageal echocardiographic analysis of color Doppler characteristics of mitral valvular regurgitation jets. DESIGN: Transesophageal echocardiographic prospective study. SETTING: Ambulatory patients referred to Echocardiographic Laboratory of Gregorio Marañon General Hospital, Madrid, Spain. MATERIAL AND METHODS: We studied a group of 100 consecutive patients with mitral regurgitation diagnosis. In each patient we calculated the degree of severity, percentage of wall intersection, maximal traced area, axis direction, atrial depth, maximal transversal diameter, perimeter and angle of the mitral regurgitation jet. We divided the entire population in three different groups according to the jet direction in central (CJ), eccentric (EJ) and wall jets (WJ). MAIN RESULTS: The direction of the mitral regurgitation jet was central in 49%, eccentric in 33% and impinging the left atrial wall in 18%. The mitral regurgitation jet angle was in the CJ 80 +/- 11 degrees, EJ 33 +/- 10 degrees and WJ 6 +/- 7 degrees. Maximal mitral regurgitant traced area in CJ was 732 +/- 104 mm2, EJ was 593 +/- 110 mm2 and WJ was 267 +/- 80 mm2. Maximal regurgitant jet depth in CJ was 36 +/- 17 mm, EJ 30 +/- 15 mm and WJ 49 +/- 14 mm. The perimeter of the mitral regurgitation jet in the CJ was 87 +/- 22 mm, EJ was 68 +/- 22 mm and WJ was 92 +/- 30 mm. CONCLUSIONS: Color Doppler quantification criteria are not useful in all patients with mitral regurgitation jets. The presence of atrial walls close to the mitral regurgitation jet area is an important factor in the mitral regurgitation color Doppler evaluation.

[A pulsed Doppler transesophageal echocardiographic study of pulmonary venous flow in mitral regurgitation jets in the parietal direction]. / Estudo Doppler pulsado do fluxo venoso pulmonar por ecocardiografia transesofágica em jactos de regurgitação mitral de direcção parietal.

OBJECTIVE: Transesophageal echocardiographic analysis of the degree of severity of mitral regurgitation eccentric wall jets by color Doppler and pulsed Doppler interrogation of the pulmonary venous flow. DESIGN: Transesophageal echocardiographic prospective study. SETTING: consecutive out and in patients referred to the Echocardiographic Laboratory of Gregorio Marañon General Hospital, Madrid, Spain. MATERIAL AND METHODS: We studied 90 consecutive patients with the clinical and echocardiographic diagnosis of valvular mitral regurgitation. In each patient through pulsed Doppler transesophageal echocardiographic technique, we measured the peak velocities and areas of systolic forward flow and systolic reversed flow of the left superior pulmonary vein. By pulsed color Doppler transesophageal echocardiographic technique, we calculated total area, severity and spatial direction of the mitral regurgitant jet. MAIN RESULTS: There were 80% (72/90) of patients included in the JC group and 20% (18/90) in the JP group. The color Doppler maximal area in the JC group was 484 +/- 118 mm2 and 445 +/- 79 mm2 (p = NS) in the JP group. Mild mitral regurgitation was present in 32% (23/72) and 55% (10/18) of the patients in the JC and JP groups (p < 0.01) respectively. Severe mitral regurgitation was present in 29% (21/72) and 0% (0/18) of the same groups (p < 0.0001). Peak velocity of pulsed Doppler pulmonary venous systolic forward flow in JC and JP groups was 47 +/- 7 cm/sec and 29 +/- 8 cm/sec respectively (p < 0.01). Maximal area of pulmonary venous flow wave in JC and JP groups was 1215 +/- 140 mm2 and 568 +/- 176 mm2 (p < 0.001) respectively. Peak velocity of reversed systolic pulmonary venous flow in JC and JP groups was 28 +/- 10 cm/sec and 46 +/- 8 cm/sec (p < 0.01) respectively. Maximal area of reversed pulmonary venous flow of JC and JP groups was 124 +/- 30 mm2 and 389 +/- 40 mm2 (p < 0.001) respectively. CONCLUSIONS: Color Doppler echocardiographic evaluation of mitral regurgitation wall jets, is not an exact method to quantify their degree of severity. In the assessment of extreme eccentric mitral regurgitation jets that interact with the atrial wall, the color Doppler quantification criteria is not sufficient. In these cases of mitral regurgitation wall jets, pulmonary venous pulsed Doppler flow criteria can be useful.

[Transesophageal echocardiography study with dynamic spontaneous contrast of the left atrial appendage, its relationship with the anatomy and thrombus formation]. / Estudo ecocardiográfico transesofágico do contraste espontâneo dinâmico no apêndice auricular esquerdo, sua relação com a anatomia e formação de trombos.

OBJECTIVE: Transesophageal two-dimensional echocardiographic study of anatomical characteristics of the left atrial appendage and its relation to spontaneous dynamic echocardiographic contrast. DESIGN: Outpatients undergoing a prospective two-dimensional transesophageal echocardiographic study. SETTING: Consecutive outpatients studied at the Echocardiographic Laboratory of Gregorio Marañon General Hospital, Madrid. MATERIAL AND METHODS: In each patient at the level of the left atrial appendage we calculated the following transesophageal echocardiographic parameters: end-systolic and end-diastolic maximal longitudinal and transversal diameters, total systolic and diastolic areas, percentage of systolic fractional shortening, presence of left atrial appendage thrombus and spontaneous dynamic echo-contrast. MAIN RESULTS: Left atrial appendage spontaneous dynamic contrast was observed in 48% of the total population. In the group of patients with left atrial spontaneous echo-contrast we observed larger longitudinal systolic (44 +/- 14 mm vs 28 +/- 13 mm, p = 0.01) and diastolic (52 +/- 16 mm vs 38 +/- 12 mm, p = 0.005) diameters, larger transversal systolic (25 +/- 10 mm vs 19 +/- 6 mm, p = 0.03) and diastolic (28 +/- 8 mm vs 25 +/- 9 mm, p = NS) diameters and also larger systolic (601 +/- 204 mm2 vs 337 +/- 110 mm2, p < 0.0001) and diastolic (715 +/- 230 mm2 vs 507 +/- 184 mm2, p = 0.001) areas, compared to the group without this dynamic echocardiographic phenomena. Left atrial appendage percentage of fractional shortening was considerably reduced in patients with spontaneous dynamic echo-contrast (15 +/- 14% vs 39 +/- 18%, p = 0.001) and related to local thrombus formation (13% vs 1%, p < 0.001). CONCLUSIONS: Left atrial spontaneous dynamic echo-contrast is more common in patients with enlarged left atrial appendage systo-diastolic diameters and areas. In this group of patients the presence of left atrial spontaneous echo-contrast is related to a significant reduction in left atrial appendage contractile function and thrombus formation. Parameter analysis of left atrial appendage anatomy by two-dimensional transesophageal echocardiography may have clinical relevance in the assessment of patients with high risk for left atria thromboembolic phenomena.

[Meaning of mosaic color area in mitral regurgitation. Echocardiographic transesophageal study]. / Significado da área de mosaico cor na regurgitação mitral. Estudo ecocardiográfico transesofágico.

OBJECTIVE: The purpose of our study was to analyse the meaning of total and mosaic color Doppler area of the mitral regurgitation jet, in terms of the degree of mitral regurgitation severity. PATIENTS: In and out patients referred to the Echocardiographic Laboratory of Gregorio Marañon General Hospital, Madrid. SETTING: Transesophageal echocardiographic prospective study MATERIAL AND METHODS: By pulsed and color Doppler transesophageal approach we studied 94 consecutive patients with mitral regurgitation diagnosis. We divided the entire population in three groups according to the degree of transthoracic mitral regurgitation severity and mitral regurgitation color area index (Groups I, II and III). In each patient we systematically measured the regurgitant maximal area (AT) and of the aliasing color area, as well as maximal peak velocity (VIS) and area (AIS) of the reversed pulmonary venous pulsed Doppler flow obtained at the level of the left upper pulmonary vein. RESULTS: For the group I, color Doppler AT was 411 +/- 315 mm2 and AN was 204 +/- 123 mm2 (R = 0.25), pulmonary venous pulsed Doppler VIS was 4 +/- 8 cm/sec (R = NS for AT and 0.79 for AN) and AIS was 9 +/- 6 mm2 (R = NS for AT and 0.82 for AN). In the group II, color Doppler AT was 802 +/- 447 mm2, AN was 671 +/- 307 mm2 (R = 0.42). the pulmonary venous pulsed Doppler VIS was 22 +/- 12 cm/sec (R = NS for AT and 0.66 for AN). In the group III we obtained an AT value of 1174 +/- 462 mm2 and an AN value of 1092 +/- 417 mm2 (R = 0.62). In this group the pulmonary venous pulsed Doppler VIS was 50 +/- 13 cm/sec (R = 0.57 for AT and 0.76 for AN) and the correspondent AIS was 671 +/- 570 mm2 (R = 0.38 for AT and 0.91 for AN). CONCLUSIONS: Mosaic transesophageal echocardiographic color Doppler area of mitral regurgitant jets has a direct relationship with the reversal criteria of pulsed Doppler pulmonary venous flow. This relationship is greater than the total color Doppler area of the same regurgitant jet. The mosaic color Doppler area of mitral regurgitant jets is a more correct estimation of the systolic variation of left atrial pressure, when compared with the total color area of mitral regurgitation.

[Occurrence of dynamic atrial spontaneous contrast in patients with mitral disease]. / Estudo da ocorrência de contraste espontâneo dinâmico intra-auricular em pacientes com doença mitral.

OBJECTIVE: The aim of this study was to analyze, through transesophageal echocardiography, different factors related to left atrial spontaneous echocardiographic formation. DESIGN: Transthoracic and transesophageal comparative study of left atrial thrombotic phenomena. SETTING: Ambulatory and in hospital patients referred to Gregorio Marañon General Hospital Echocardiographic Laboratory. PATIENTS: 120 consecutive patients with mitral valve disease or prosthesis were included in this transesophageal echocardiographic prospective study. All patients were divided in two groups, according with left atrial spontaneous contrast. In each patient we measured total left atrial area, rhythm abnormalities, mitral valve area, left atrial cavity thrombus and maximal mitral regurgitation area. MEASUREMENTS AND RESULTS: Transthoracic echocardiography did not detect any patient with left atrial spontaneous contrast, compared to 57.5% diagnosed through the transesophageal technique. Transesophageal echocardiography diagnosed left atrial thrombosis in 19% (n = 23) of patients compared to 1% (n = 2) through the transthoracic technique. In the group with left atrial contrast, 59% of patients had mitral regurgitation less than 600 mm2, 64% were in atrial fibrillation and left atrial total area was 28 +/- 10.8 mm2. CONCLUSIONS: Transesophageal echocardiography is the technique of choice to diagnose, with greater security, left atrial cavity thrombosis, and establish the relationship of echocardiographic variables and left atrial thrombotic phenomena. Among these echocardiographic factors, left atrial dynamic spontaneous echocontrast is fundamental.