997 resultados para agenesis of the corpus callosum


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A multimodal MR study including relaxometry, diffusion tensor imaging (DTI), and MR spectroscopy was performed on patients with classical phenylketonuria (PKU) and matched controls, to improve our understanding of white matter (WM) lesions. Relaxometry yields information on myelin loss or malformation and may substantiate results from DTI attributed to myelin changes. Relaxometry was used to determine four brain compartments in normal-appearing brain tissue (NABT) and in lesions: water in myelin bilayers (myelin water, MW), water in gray matter (GM), water in WM, and water with long relaxation times (cerebrospinal fluid [CSF]-like signals). DTI yielded apparent diffusion coefficients (ADCs) and fractional anisotropies. MW and WM content were reduced in NABT and in lesions of PKU patients, while CSF-like signals were significantly increased. ADC values were reduced in PKU lesions, but also in the corpus callosum. Diffusion anisotropy was reduced in lesions because of a stronger decrease in the longitudinal than in the transverse diffusion. WM content and CSF-like components in lesions correlated with anisotropy and ADC. ADC values in lesions and in the corpus callosum correlated negatively with blood and brain phenylalanine (Phe) concentrations. Intramyelinic edema combined with vacuolization is a likely cause of the WM alterations. Correlations between diffusivity and Phe concentrations confirm vulnerability of WM to high Phe concentrations.

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Progesterone secretion is crucial for maintaining pregnancy to parturition in mammalian species, and in cattle the corpus luteum is the primary source of this hormone. This study determined the roles of prolactin (PRL), growth hormone (GH) and luteinizing hormone (LH) in the luteotropic process in beef heifers hypophyseal stalk-transected (HST, n = 7) or sham operated on (SOC, n = 9) during midgestation. The main finding was that endogenous PRL and GH maintained progesterone secretion in HST heifers similar to that in SOC throughout pregnancy. Serum PRL averaged 37 vs 187 and GH 2 vs 4 ng/ml in HST compared with SOC, whereas LH abruptly decreased to undetectable levels after HST compared with a modest 0A4 ng/ml in SOC heifers. The second finding was that parturition and lactation occurred in HST heifers with calf delivery induced to occur at the same time as SOC. Milk production in HST animals was severely limited, and postpartum estrus obliterated compared with SOC. The suckling stimulus sustained milk ejection in HST heifers in spite of diminished PRL and GH secretion. The results suggest that PRL, GH and possibly placental lactogen are luteotropic during pregnancy in cattle.

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Progesterone secretion is crucial for maintaining pregnancy to parturition in mammalian species, and in cattle the corpus luteum is the primary source of this hormone. This study determined the roles of prolactin (PRL), growth hormone (GH) and luteinizing hormone (LH) in the luteotropic process in beef heifers hypophyseal stalk-transected (HST, n = 7) or sham operated on (SOC, n = 9) during midgestation. The main finding was that endogenous PRL and GH maintained progesterone secretion in HST heifers similar to that in SOC throughout pregnancy. Serum PRL averaged 37 vs. 187 and GH 2 vs. 4 ng/ml in HST compared with SOC, whereas LH abruptly decreased to undetectable levels after HST compared with a modest 0.4 ng/ml in SOC heifers. The second finding was that parturition and lactation occurred in HST heifers with calf delivery induced to occur at the same time as SOC. Milk production in HST animals was severely limited and postpartum estrus obliterated compared with SOC. The suckling stimulus sustained milk ejection in HST heifers in spite of diminished PRL and GH secretion. The results suggest that PRL, GH, and possibly placental lactogen are luteotropic during pregnancy in cattle.

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Previous studies have demonstrated that habitual physical activity is associated with a reduced risk of incident coronary heart disease (CHD). However, the role of physical activity in lowering the risk of all-cause mortality, CHD mortality, reinfarction, or receipt of a revascularization procedure after a first myocardial infarction (MI) remains unresolved, particularly in minority populations. To investigate the associations between physical activity and risk of all-cause mortality, CHD mortality, reinfarction, and receipt of a revascularization procedure, this study was conducted among Mexican-American and non-Hispanic white women and men who survived a first MI. The Corpus Christi Heart Project, a population-based cardiovascular surveillance study, provide data which included vital status, survival time, medical history, CHD risk factor information, including level of physical activity among Mexican-American and non-Hispanic white adults who had experienced a first MI between May, 1988 and April, 1990. MI patients were interviewed at baseline and annually thereafter until their death or through May, 1995. A categorical variable was created to reflect change in level of physical activity following the first MI; categories included (1) sedentary with no change, (2) decreased activity, (3) increased activity, and (4) moderate activity with no change (the referent group). Proportional hazards regression analyses were used to assess the relationship of level of physical activity and risk of death, reinfarction, or receipt of a revascularization procedure adjusting for age, sex, ethnicity, severity of MI, and CHD risk factor status. Over a 7-year follow-up period, the relative risk (95% confidence intervals) of all-cause mortality was 4.67 (2.27, 9.60) for the sedentary-no change group, 2.33 (0.96, 5.67) for the decreased activity group, and 0.52 (0.11, 2.41) for the increased activity group. The relative risk of CHD mortality was 6.92 (2.05, 23.34) for the sedentary-no change group, 2.40 (0.55, 10.51) for the decreased activity group, and 1.58 (0.26, 9.65) for the increased activity group. The relative risk for reinfarction was 2.50 (1.52, 4.10) for the sedentary-no change group, 2.26 (1.24, 4.12) for the decreased activity group, and 0.52 (0.21, 1.32) for the increased activity group. Finally, the relative risk for receipt of a revascularization procedure was 0.65 (0.39, 1.07) for the sedentary-no change group, 0.45 (0.22, 0.92) for the decreased activity group, and 1.01 (0.51, 2.02) for the increased activity group. No interactions were observed for ethnicity or severity of first MI. These results are consistent with the hypothesis that moderate physical activity is independently associated with a lower risk of all-cause mortality, CHD mortality, and reinfarction, but not revascularization, among Mexican-American and non-Hispanic white, female and male, first MI patients. These results also support the current recommendation that physical activity plays an important role in the secondary prevention of CHD. ^

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Partial phallectomy or en bloc resection are surgical methods to address pathological conditions of the penis and/or prepuce including neoplasia, trauma, habronemiasis, chronic paraphimosis or permanent penile paralysis, and priapism. Haemorrhage associated with urination is a common complication observed after penile surgery but usually resolves spontaneously without specific treatment. This report describes a case of post urination haemorrhage (PUH) that recurred with each urination and persisted without significant improvement for a period of 2 weeks following en bloc resection of the penis and the prepuce. A perineal incision (PI) into the corpus spongiosum of the penis (CSP) resolved PUH by decreasing the blood pressure in the CSP distal to the PI. We propose that PI of the CSP can be an effective method to address PUH after penile surgery and may decrease time of hospitalisation for horses affected with PUH after phallectomy procedures.

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We report on the molecular characterization of a microdeletion of approximately 2.5 Mb at 2p11.2 in a female baby with left congenital aural atresia, microtia, and ipsilateral internal carotid artery agenesis. The deletion was characterized by fluorescence in situ hybridization, array comparative genomic hybridization, and whole genome re-sequencing. Among the genes present in the deleted region, we focused our attention on the FOXI3 gene. Foxi3 is a member of the Foxi class of Forkhead transcription factors. In mouse, chicken and zebrafish Foxi3 homologues are expressed in the ectoderm and endoderm giving rise to elements of the jaw as well as external, middle and inner ear. Homozygous Foxi3-/- mice have recently been generated and show a complete absence of the inner, middle, and external ears as well as severe defects in the jaw and palate. Recently, a 7-bp duplication within exon 1 of FOXI3 that produces a frameshift and a premature stop codon was found in hairless dogs. Mild malformations of the outer auditory canal (closed ear canal) and ear lobe have also been noted in a fraction of FOXI3 heterozygote Peruvian hairless dogs. Based on the phenotypes of Foxi3 mutant animals, we propose that FOXI3 may be responsible for the phenotypic features of our patient. Further characterization of the genomic region and the analysis of similar patients may help to demonstrate this point. © 2015 Wiley Periodicals, Inc.

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Introduction: Schizophrenia patients frequently suffer from complex motor abnormalities including fine and gross motor disturbances, abnormal involuntary movements, neurological soft signs and parkinsonism. These symptoms occur early in the course of the disease, continue in chronic patients and may deteriorate with antipsychotic medication. Furthermore gesture performance is impaired in patients, including the pantomime of tool use. Whether schizophrenia patients would show difficulties of actual tool use has not yet been investigated. Human tool use is complex and relies on a network of distinct and distant brain areas. We therefore aim to test if schizophrenia patients had difficulties in tool use and to assess associations with structural brain imaging using voxel based morphometry (VBM) and tract based spatial statistics (TBSS). Methode: In total, 44 patients with schizophrenia (DSM-5 criteria; 59% men, mean age 38) underwent structural MR imaging and performed the Tool-Use test. The test examines the use of a scoop and a hammer in three conditions: pantomime (without the tool), demonstration (with the tool) and actual use (with a recipient object). T1-weighted images were processed using SPM8 and DTI-data using FSL TBSS routines. To assess structural alterations of impaired tool use we first compared gray matter (GM) volume in VBM and white matter (WM) integrity in TBSS data of patients with and without difficulties of actual tool use. Next we explored correlations of Tool use scores and VBM and TBSS data. Group comparisons were family wise error corrected for multiple tests. Correlations were uncorrected (p < 0.001) with a minimum cluster threshold of 17 voxels (equivalent to a map-wise false positive rate of alpha < 0.0001 using a Monte Carlo procedure). Results: Tool use was impaired in schizophrenia (43.2% pantomime, 11.6% demonstration, 11.6% use). Impairment was related to reduced GM volume and WM integrity. Whole brain analyses detected an effect in the SMA in group analysis. Correlations of tool use scores and brain structure revealed alterations in brain areas of the dorso-dorsal pathway (superior occipital gyrus, superior parietal lobule, and dorsal premotor area) and the ventro-dorsal pathways (middle occipital gyrus, inferior parietal lobule) the action network, as well as the insula and the left hippocampus. Furthermore, significant correlations within connecting fiber tracts - particularly alterations within the bilateral corona radiata superior and anterior as well as the corpus callosum -were associated with Tool use performance. Conclusions: Tool use performance was impaired in schizophrenia, which was associated with reduced GM volume in the action network. Our results are in line with reports of impaired tool use in patients with brain lesions particularly of the dorso-dorsal and ventro-dorsal stream of the action network. In addition an effect of tool use on WM integrity was shown within fiber tracts connecting regions important for planning and executing tool use. Furthermore, hippocampus is part of a brain system responsible for spatial memory and navigation.The results suggest that structural brain alterations in the common praxis network contribute to impaired tool use in schizophrenia.

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Aim Our aim was to discriminate different species of Pinus via pollen analysis in order to assess the responses of particular pine species to orbital and millennial-scale climate changes, particularly during the last glacial period. Location Modern pollen grains were collected from current pine populations along transects from the Pyrenees to southern Iberia and the Balearic Islands. Fossil pine pollen was recovered from the south-western Iberian margin core MD95-2042. Methods We measured a set of morphological traits of modern pollen from the Iberian pine species Pinus nigra, P. sylvestris, P. halepensis, P. pinea and P. pinaster and of fossil pine pollen from selected samples of the last glacial period and the early to mid-Holocene. Classification and regression tree (CART) analysis was used to establish a model from the modern dataset that discriminates pollen from the different pine species and allows identification of fossil pine pollen at the species level. Results The CART model was effective in separating pollen of P. nigra and P. sylvestris from that of the Mediterranean pine group (P. halepensis, P. pinea and P. pinaster). The pollen of Pinus nigra diverged from that of P. sylvestris by having a more flattened corpus. Predictions using this model suggested that fossil pine pollen is mainly from P. nigra in all the samples analysed. Pinus sylvestris was more abundant in samples from Greenland stadials than Heinrich stadials, whereas Mediterranean pines increased in samples from Greenland interstadials and during the early to mid-Holocene. Main conclusions Morphological parameters can be successfully used to increase the taxonomic resolution of fossil pine pollen at the species level for the highland pines (P. nigra and P. sylvestris) and at the group of species level for the Mediterranean pines. Our study indicates that P. nigra was the dominant component of the last glacial south-western/central Iberian pinewoods, although the species composition of these woodlands varied in response to abrupt climate changes.

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Pem, a member of the PEPP homeobox family, is expressed in somatic cells in male and female reproductive tissues. In the adult murine testis, Pem is specifically expressed in Sertoli cells, where it is restricted to stages IV–VIII of the seminiferous epithelial cycle. To identify Pem's function in Sertoli cells, transgenic mice were generated that express Pem in Sertoli cells during all stages of the seminiferous epithelial cycle. This resulted in an increase in double-strand DNA breaks in preleptotene spermatocytes and single-strand DNA breaks in elongating spermatids. My results suggest that Pem regulates Sertoli-cell genes that encode secreted or cell-surface proteins that serve to control premeiotic DNA replication, DNA repair, and/or chromatin remodeling in the adjacent germ cells. Three additional transgenic mouse containing varying lengths of the Pem male-specific promoter (Pp) were generated to identify the sequences responsible for regulating Pem expression in the testis and epididymis. My analysis suggests that there are at least two regulatory regions in the Pem Pp. In the testis, region II directs androgen-dependent expression specifically in Sertoli cells whereas region I fine-tunes stage-specific expression by acting as a negative regulator. In the epididymis, region II confers androgen-dependent, developmentally-regulated expression in the caput whereas region I prevents inappropriate expression in the corpus. I also report the identification and characterization of two human PEPP family members related to Pem that I have named hPEPP1 and hPEPP2. The hPEPP1 and hPEPP2 homeodomains are more closely related to PEPP subfamily homeodomains than to any other homeodomain subfamily. Both genes are localized to the specific region of the human X chromosome that shares synteny with the region on the murine X chromosome containing three PEPP homeobox genes, Pem, Psx-1, and Psx-2. hPEPP1 and hPEPP2 mRNA expression is restricted to the testis but is aberrantly expressed in tumor cells of different origins, analogous to the expression pattern of Pem but not of Psx-1 or Psx-2. Unlike all known PEPP members, neither hPEPP1 nor hPEPP2 are expressed in placenta, which suggests that the regulation of the PEPP family has undergone significant alteration since the split between hominids and rodents. ^

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Purpose. We performed a case-comparison study to describe the characteristics of LUS tumors and their association with risk factors for endometrial cancer. ^ Patients and Methods. From January 1996 through October 2007, 3,892 women were identified with a diagnosis of primary endometrial carcinoma or primary cervical adenocarcinoma. Pathology records from the 1,009 women who had a hysterectomy were reviewed. Subjects were included in the LUS group only if the tumor was clearly originating from the area between the lower corpus and upper cervix in the hysterectomy specimen. The LUS group was compared to all patients with endometrial corpus carcinoma who underwent hysterectomy at our institution in a 12-month period randomly selected from the study period. Risk factors for endometrial carcinoma such as body mass index (BMI) and Lynch Syndrome were assessed. Expression of estrogen receptor (ER), vimentin, carcinoembryonic antigen (CEA), p16, and human papilloma virus DNA (HPV DNA) was assessed; this panel is known to be effective in distinguishing adenocarcinomas of endometrial versus endocervical origin. Fisher's Exact, Chi-square, Mann-Whitney, and Student's t-tests were utilized for statistical analysis. ^ Results. Thirty-five of 1,009 women had endometrial carcinoma of the LUS (3.5%; 95% CI: 2–4%). Compared to patients with corpus tumors, LUS patients were younger (54.2 vs. 62.9 years, P = .001), had higher stage (P < .001), and more invasive tumors (P = .001). Preoperative diagnosis of the LUS tumors more frequently included the possibility of endocervical adenocarcinoma ( P < .001), leading to preoperative radiation therapy in 4 patients. Median BMI was similar in the LUS and corpus groups. Seventy-three percent of the available LUS tumors had a similar immunohistochemical expression pattern to conventional endometrioid adenocarcinoma. Because of the young median age for the LUS group, we performed immunohistochemistry for Lynch syndrome-associated DNA mismatch repair proteins MLH1, MSH2, MSH6, and PMS2. Microsatellite instability testing (MSI) and MLH1 promoter hypermethylation were performed when indicated. Thirty-six percent of the LUS tumors were MSI-high. Ten of thirty-five (29%) women with LUS tumors were either confirmed to have Lynch Syndrome or were strongly suspected to have Lynch Syndrome based on tissue-based molecular assays (95% CI, 16 to 45%). ^ Conclusions. Endometrial carcinoma arising in the LUS is a clinical and pathologic entity which can be diagnostically confused with cervical adenocarcinoma. In general, LUS tumors can be correctly identified as being endometrial carcinoma using the immunohistochemical panel noted above. The prevalence of Lynch Syndrome in patients with LUS tumors is much greater than that of the general endometrial cancer population (1.8%) or in endometrial cancer patients younger than 50 years of age (8–9%). Based on our results, the possibility of Lynch Syndrome should be considered in women with LUS tumors. ^

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Coronary perfusion with thrombolytic therapy and selective reperfusion by percutaneous transluminal coronary angioplasty (PTCA) were examined in the Corpus Christi Heart Project, a population-based surveillance program for hospitalized acute myocardial infarction (MI) patients in a biethnic community of Mexican-Americans (MAs) and non-Hispanic whites (NHWs). Results were based on 250 (12.4%) patients who received thromobolytic therapy in a cohort of 2011 acute MI cases. Out of these 107 (42.8%) underwent PTCA with a mean follow-up of 25 months. There were 186 (74.4%) men and 64 (25.6%) women; 148 (59.2%) were NHWs, 86 (34.4%) were MAs. Thrombolysis and PTCA were performed less frequently in women than in men, and less frequently in MAs than in NHWs.^ According to the coronary reperfusion interventions used, patients were divided in two groups, those that received no-PTCA (57.2%) and the other that underwent PTCA (42.8%) after thrombolysis. The case-fatality rate was higher in no-PTCA patients than in the PTCA (7.7% versus 5.6%), as was mortality at one year (16.2% versus 10.5%). Reperfusion was successful in 48.0% in the entire cohort and (51.4% versus 45.6%) in the PTCA and no-PTCA groups. Mortality in the successful reperfusion patients was 5.0% compared to 22.3% in the unsuccessful reperfusion group (p = 0.00016, 95% CI: 1.98-11.6).^ Cardiac catheterization was performed in 86.4% thrombolytic patients. Severe stenosis ($>$75%) obstruction was present most commonly in the left descending artery (52.8%) and in the right coronary artery (52.8%). The occurrence of adverse in-hospital clinical events was higher in the no-PTCA as compared to the PTCA and catheterized patients with the exception of reperfusion arrythmias (p = 0.140; Fisher's exact test p = 0.129).^ Cox regression analysis was used to study the relationship between selected variables and mortality. Apart from successful reperfusion, age group (p = 0.028, 95% CI: 2.1-12.42), site of acute MI index (p = 0.050) and ejection-fraction (p = 0.052) were predictors of long-term survival. The ejection-fraction in the PTCA group was higher than (median 78% versus 53%) in the no-PTCA group. Assessed by logistic regression analysis history of high cholesterol ($>$200mg/dl) and diabetes mellites did have significant prognostic value (p = 0.0233; p = 0.0318) in long-term survival irrespective of treatment status.^ In conclusion, the results of this study support the idea that the use of PTCA as a selective intervention following thrombolysis improves survival of patients with acute MI. The use of PTCA in this setting appears to be safe. However, we can not exclude the possibility that some of these results may have occurred due to the exclusion from PTCA of high risk patients (selection bias). ^

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A large number of later Neolithic sites (3900–3500BC) in Switzerland, Southern Germany and Eastern France offer outstandingly well preserved archaeological materials from cultural layers. Due to the wide use of dendrochronology, settlement remains and artefact assemblages can now be placed into a precise and fixed chronological framework, thus presenting a unique case within prehistoric archaeology. In earlier research, chronological and regional units were constructed on the basis of pottery. These spacial and temporal units of typical pottery sets were understood as Neolithic cultures, as culturally more or less homogenous entities connected with (ethnic) identities. Today, with a larger data corpus of excavated settlements at hand, we can begin to understand that this period of the past was in fact characterised by a multitude of cultural entanglements and transformations. This is indicated by the occurrence of local and non-local pottery styles in one and the same settlement: for example typically local Cortaillod pottery is found together with NMB-styled pottery in settlements at Lake Neuchâtel or Michelsberg pottery is regularly occurring in settlements at Lake Constance where Pfyn pottery style is the typical local one. These and many more examples show that there must have been complex entanglements of social ties expanding between Eastern France, Southern Germany and the Swiss Plateau. Given these circumstances the former notions of Neolithic culture should be critically revised. Therefore, in late 2014, the Prehistoric Archaeology Department at the Archaeological Institute of University of Berne started a four-year research project funded by Swiss National Science Foundation in late 2014: ‘Mobilities, Entanglements and Transformations in Neolithic Societies of the Swiss Plateau (3900-3500 BC)’. It’s objective is to address the topic sketched above by adopting a mixed methods research (MMR)-design combining qualitative and quantitative approaches from archaeology and archaeometry. The approach is theoretically based on Pierre Bourdieu’s reflexive sociology and his concept of habitus but includes further concepts of practice theories. By shifting the focus to the movement of people, ideas and things – to pottery production practices in contexts of mobility – a deeper understanding of the transformative capacities of encounters can be achieved. This opens the path for new insights of Neolithic societies including social, cultural and economic dynamics that were underestimated in former research.

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This paper presents an approach to compare two types of data, subjective data (Polarity of Pan American Games 2011 event by country) and objective data (the number of medals won by each participating country), based on the Pearson corre- lation. When dealing with events described by people, knowledge acquisition is difficult because their structure is heterogeneous and subjective. A first step towards knowing the polarity of the information provided by people consists in automatically classifying the posts into clusters according to their polarity. The authors carried out a set of experiments using a corpus that consists of 5600 posts extracted from 168 Internet resources related to a specific event: the 2011 Pan American games. The approach is based on four components: a crawler, a filter, a synthesizer and a polarity analyzer. The PanAmerican approach automatically classifies the polarity of the event into clusters with the following results: 588 positive, 336 neutral, and 76 negative. Our work found out that the polarity of the content produced was strongly influenced by the results of the event with a correlation of .74. Thus, it is possible to conclude that the polarity of content is strongly affected by the results of the event. Finally, the accuracy of the PanAmerican approach is: .87, .90, and .80 according to the precision of the three classes of polarity evaluated.

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CREB, the cAMP response element binding protein, is a key transcriptional regulator of a large number of genes containing a CRE consensus sequence in their upstream regulatory regions. Mice with a hypomorphic allele of CREB that leads to a loss of the CREBα and Δ isoforms and to an overexpression of the CREBβ isoform are viable. Herein we report the generation of CREB null mice, which have all functional isoforms (CREBα, β, and Δ) inactivated. In contrast to the CREBαΔ mice, CREB null mice are smaller than their littermates and die immediately after birth from respiratory distress. In brain, a strong reduction in the corpus callosum and the anterior commissures is observed. Furthermore, CREB null mice have an impaired fetal T cell development of the αβ lineage, which is not affected in CREBαΔ mice on embryonic day 18.5. Overall thymic cellularity in CREB null mice is severely reduced affecting all developmental stages of the αβ T cell lineage. In contrast γδ T cell differentiation is normal in CREB mutant mice.

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El estudio de Lakoff y Johnson Metáforas de la vida cotidiana (1980) ha dotado al campo de la metáfora de un renovado interés, y a éste siguieron numerosas publicaciones abordándolo desde diversas perspectivas. Lakoff y Johnson (1980) aseguran que la metáfora es, de hecho, una característica del pensamiento y, por consiguiente, ya no es una propiedad exclusiva del lenguaje. La metáfora sería en realidad un reflejo de cómo concebimos e interpretamos el mundo en que vivimos, en la medida en que está conformada por nuestras experiencias corporales, un fenómeno al que Lakoff y Johnson se refieren como la “mente corpórea”. La metáfora cumple la función de “comprender” y facilitar la interpretación de un ámbito o experiencia en los términos de otro ámbito o experiencia (Lakoff & Johnson, 1980: 36). Los conceptos abstractos son difíciles de ser pensados per se; consecuentemente, las personas recurren a la metáfora para concebirlos en los términos de otras nociones más concretas que están, en cierto grado, vinculadas a nuestras experiencias somáticas. Si bien no escasean las investigaciones en el campo de las metáforas, parece haber, sin embargo, cierto vacío en lo tocante a la manifestación de la metáfora en modos distintos del modo verbal. Forceville (2009: 19) afirma que uno de los principios fundamentales de la Teoría de la Metáfora Conceptual es la idea de que el variado empleo de metáforas por parte del ser humano sugiere “que piensa en gran medida metafóricamente”. Esto lleva a la conclusión de que la manifestación de la metáfora debería estar presente en los diversos modos del pensamiento, y no únicamente en el verbal. Estos otros modos de pensamiento incluyen, entre otros, las imágenes, la música, los sonidos y los gestos. Asimismo, la mayoría de estudios que se han realizado en el área de las metáforas multimodales ha sido aplicada al terreno de la publicidad. Los anunciantes parecen advertir el ! 2! poder que se invierte en las metáforas, y las usan profusamente para transmitir mensajes a los consumidores. No obstante, recientemente existe un nuevo interés por investigar el uso de metáforas multimodales en las caricaturas (véase, por ejemplo, El Refaie 2003, 2009; Schilperoord y Maes 2009; Yus 2009; Bergen 2003; Marin Aresse 2008). Las tiras cómicas se distinguen de los anuncios principalmente por el hecho de que las caricaturas transmiten una postura negativa frente a un sujeto particular, mientras que los anuncios presentan una actitud positiva. Igualmente, les diferencia el hecho de que las tiras cómicas requieren un conocimiento social y político específico. El presente escrito examina y compara el uso de metáforas multimodales en caricaturas políticas – tanto inglesas como árabes – que retratan la Primavera Árabe en Egipto, con el fin de determinar: (1) si la mayoría de caricaturas son conceptualmente específicas o culturalmente específicas; (2) los principales dominios fuente empleados por los caricaturistas ingleses y árabes para interpretar la Primavera Árabe; (3) si hay semejanzas o diferencias entre las caricaturas inglesas y las árabes en su elección del dominio meta; y (4) observar también cómo los distintos modos (aquí esencialmente los modos verbal y pictórico) contribuyen a representar la Primavera Árabe. El corpus para este estudio se compone de un total de 50 tiras cómicas, 25 de ellas inglesas y las 25 restantes árabes. En cada una de estas tiras debe haber al menos una metáfora que representa la Primavera Árabe o alguno de sus subtemas. Las tiras han sido seleccionadas aleatoriamente a través de Internet. Para el análisis, la investigadora ha seguido el marco teórico propuesto por Bounegru y Forceville (2011) en cuanto a la determinación de metáforas en general, así como la determinación de metáforas multimodales de tipo verbovisual en particular. Por cada tira cómica se ha llevado a cabo un análisis independiente, determinando el dominio fuente y el dominio meta, las metáforas, las asignaciones, qué se está representando verbalmente y qué se representa pictóricamente. Además, la autora ha analizado ! 3! posteriormente si estas metáforas son culturalmente específicas o no, y/o si están relacionadas con metáforas más genéricas o universales. El análisis que comprende este trabajo se divide en dos secciones. La primera parte es un estudio detallado de los dos corpora, abordando los distintos escenarios de los dominios fuente empleados por los dibujantes según su similitud. Esta sección presenta a su vez un análisis de los diversos modos que se utilizan para revelar el dominio fuente así como el dominio meta. Del mismo modo, se incluyen las metáforas específicas manejadas en cada tira cómica y, cuando se da el caso, aquellas metáforas genéricas o universales a las que remite. La segunda sección del análisis presenta una comparativa entre ambos corpora basada en el análisis expuesto en la primera parte. Además, trata varios de los fenómenos lingüísticos a los que han recurrido frecuentemente los dibujantes ingleses y árabes. Estos fenómenos son principalmente la metonimia y la personificación. Igualmente, en esta sección la autora investiga en mayor profundidad las metáforas usadas por los dibujantes ingleses y los árabes, determinando si son ora conceptualmente específicas, ora culturalmente específicas, a partir del hecho de que las metáforas sirven como herramienta para reconocer la forma en que personas distintas, o bien culturas distintas, interpretan varias cuestiones. Por ejemplo, a la hora de conceptualizar el futuro, algunas culturas lo representan espacialmente como delante del hablante, mientras que otras se refieren al mismo como localizado detrás del sujeto (Lakoff y Johnson 1980: 14). Este trabajo ha permitido varios hallazgos. En cuanto a las metáforas empleadas para representar la Primavera Árabe, tanto las tiras inglesas como las árabes han recurrido a una cierta variedad de metáforas. Algunas de las tiras presentan más de una metáfora operando a la vez. Los dibujantes ingleses y árabes parecen haberse apoyado siempre en el modo pictórico para presentar el dominio fuente, así como en el modo verbal para mostrar el dominio meta. ! 4! Además, respecto a la naturaleza de las metáforas que figuran en sendos corpora, casi todas las metáforas son conceptuales en cuanto que se corresponden con nuestras experiencias corporales; no hay, por otro lado, ninguna metáfora culturalmente específica. Asimismo, la única diferencia a este respecto entre ambos corpora es una variación en lo que constituye el prototipo de una categoría particular – aquí concretamente la categoría “primavera” en cada una de las culturas –. En las tiras inglesas, una flor es empleada para representar la primavera, mientras que en las árabes el elemento natural más frecuente para simbolizar la primavera es un árbol.