293 research outputs found

    Anatomical pathways for auditory memory II: information from rostral superior temporal gyrus to dorsolateral temporal pole and medial temporal cortex

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    Auditory recognition memory in non-human primates differs from recognition memory in other sensory systems. Monkeys learn the rule for visual and tactile delayed matching-to-sample within a few sessions, and then show one-trial recognition memory lasting 10–20 min. In contrast, monkeys require hundreds of sessions to master the rule for auditory recognition, and then show retention lasting no longer than 30–40 s. Moreover, unlike the severe effects of rhinal lesions on visual memory, such lesions have no effect on the monkeys' auditory memory performance. The anatomical pathways for auditory memory may differ from those in vision. Long-term visual recognition memory requires anatomical connections from the visual association area TE with areas 35 and 36 of the perirhinal cortex (PRC). We examined whether there is a similar anatomical route for auditory processing, or that poor auditory recognition memory may reflect the lack of such a pathway. Our hypothesis is that an auditory pathway for recognition memory originates in the higher order processing areas of the rostral superior temporal gyrus (rSTG), and then connects via the dorsolateral temporal pole to access the rhinal cortex of the medial temporal lobe. To test this, we placed retrograde (3% FB and 2% DY) and anterograde (10% BDA 10,000 mW) tracer injections in rSTG and the dorsolateral area 38DL of the temporal pole. Results showed that area 38DL receives dense projections from auditory association areas Ts1, TAa, TPO of the rSTG, from the rostral parabelt and, to a lesser extent, from areas Ts2-3 and PGa. In turn, area 38DL projects densely to area 35 of PRC, entorhinal cortex (EC), and to areas TH/TF of the posterior parahippocampal cortex. Significantly, this projection avoids most of area 36r/c of PRC. This anatomical arrangement may contribute to our understanding of the poor auditory memory of rhesus monkeys

    The influence of semantic and phonological factors on syntactic decisions: An event-related brain potential study

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    During language production and comprehension, information about a word's syntactic properties is sometimes needed. While the decision about the grammatical gender of a word requires access to syntactic knowledge, it has also been hypothesized that semantic (i.e., biological gender) or phonological information (i.e., sound regularities) may influence this decision. Event-related potentials (ERPs) were measured while native speakers of German processed written words that were or were not semantically and/or phonologically marked for gender. Behavioral and ERP results showed that participants were faster in making a gender decision when words were semantically and/or phonologically gender marked than when this was not the case, although the phonological effects were less clear. In conclusion, our data provide evidence that even though participants performed a grammatical gender decision, this task can be influenced by semantic and phonological factors

    The Human Parahippocampal Region: I. Temporal Pole Cytoarchitectonic and MRI Correlation

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    The temporal pole (TP) is the rostralmost portion of the human temporal lobe. Characteristically, it is only present in human and nonhuman primates. TP has been implicated in different cognitive functions such as emotion, attention, behavior, and memory, based on functional studies performed in healthy controls and patients with neurodegenerative diseases through its anatomical connections (amygdala, pulvinar, orbitofrontal cortex). TP was originally described as a single uniform area by Brodmann area 38, and von Economo (area TG of von Economo and Koskinas), and little information on its cytoarchitectonics is known in humans. We hypothesize that 1) TP is not a homogenous area and we aim first at fixating the precise extent and limits of temporopolar cortex (TPC) with adjacent fields and 2) its structure can be correlated with structural magnetic resonance images. We describe here the macroscopic characteristics and cytoarchitecture as two subfields, a medial and a lateral area, that constitute TPC also noticeable in 2D and 3D reconstructions. Our findings suggest that the human TP is a heterogeneous region formed exclusively by TPC for about 7 mm of the temporal tip, and that becomes progressively restricted to the medial and ventral sides of the TP. This cortical area presents topographical and structural features in common with nonhuman primates, which suggests an evolutionary development in human species

    High-quality intake of carbohydrates is associated with lower prevalence of subclinical atherosclerosis in femoral arteries: The AWHS study

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    Background and aims: High-quality of the carbohydrates consumed, apart from their total amount, appear to protect from cardiovascular disease (CVD). However, the relationship between the quality of carbohydrates and the early appearance of atherosclerosis has not yet been described. Our objective was to estimate the association between the quality of dietary carbohydrates and subclinical atherosclerosis in femoral and carotid arteries. Methods: Cross-sectional study of femoral and carotid atherosclerosis assessed using ultrasounds of 2074 middle-aged males, 50.9 (SD 3.9) years old, with no previous CVD, and pertaining to the Aragon Workers’ Health Study (AWHS) cohort. Food frequency questionnaires were used to calculate a carbohydrate quality index (CQI) defined as: consumption of dietary fiber, a lower glycemic index, the ratio of whole grains/total grains, and the ratio of solid carbohydrates/total carbohydrates. The presence of plaques across four CQI intervals was studied using adjusted logistic regression models. Results: The CQI showed a direct inverse association with subclinical atherosclerosis in femoral territories. Participants with a higher consumption of high-quality carbohydrates (13–15 points) were less likely to have femoral plaques when compared with participants in the lowest index interval (4–6 points) (OR = 0.59; 95% CI = 0.39, 0.89; p = 0.005). No association was found between the CQI and the presence of subclinical atherosclerosis in carotid territories. A lower consumption of high-quality carbohydrates tended to be associated with a greater atherosclerosis extension, considered as the odds for having more affected territories (p = 0.011). Conclusions: Among middle-aged males, a high-quality intake of carbohydrates is associated with a lower prevalence of femoral artery subclinical atherosclerosis when compared with a lower consumption. Thus, indicating an early relationship between the quality of carbohydrates and the development of CVD. © 2021 The Author(s

    Assessment of dry-aged beef from commercial aging locations across the United States

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    Modern dry-aging is a culinary-inspired practice that involves storing meat at refrigerated temperatures without protective packaging. The dry-aging process has been observed to create unique flavors. The objective of the current study was to survey commercial dry-aging facility environments and observe palatability differences related to consumer acceptance. Seventy-two bone-in beef strip loins (Institutional Meat Purchase Specification #175) were acquired. Strip loins were randomly assigned to each of ten commercial dry-aging facilities. Additionally, a set of strip loins were wet-aged at the University of Idaho meat laboratory. Strip loins were shipped overnight to respective aging locations and dry-aged for 45-days then returned overnight to the University of Idaho meat laboratory. Strip loins were fabricated into steaks, vacuum packaged, and then frozen until further analyzed. Commercial dry-aging facility cooler conditions were observed to be different (P 0.05) among treatment-locations. Consumer taste panels indicated a difference (P < 0.01) in acceptability (6.27–7.24), tenderness (6.65–7.54), and flavor (5.58–6.79) based on aging treatment-location. Overall, the findings indicate that conditions within individual dry-aging facilities aid in producing unique dry-aged beef flavors.Funded by the Idaho Beef Council. We gratefully acknowledge Idaho Beef Council’s financial support (AG3963

    Tratamiento conservador del cáncer de mama: valoración de los resultados

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    Introducción: La asociación de cirugía limitada y radioterapia es el tratamiento de elección para un gran número de mujeres con cáncer de mama; no obstante esta opción terapéutica va asociada a un número no despreciable de recidivas sobre la mama tratada (1-1,5% por año de seguimiento). Material y Métodos: Se analizan 641 casos de mujeres con cáncer de mama, tratados mediante cirugía conservadora de la mama y radioterapia y seguidos durante una media de 50 meses. La técnica consistió preferentemente en la practica de una Resección Segmentaria de mama con vaciamiento axilar, al menos de los niveles I y II (excepto en los CIS a partir de 1997), complementada con la administración de Radioterapia (45-50 Gy sobre la mama y una sobreimpresión de 15-20 Gy). Resultados: La edad media fue de 52.3 años, con extremos en 21 y 82 años El tamaño medio tumoral fue pT: 1,7 cm y el 63,1% de los casos correspondieron a tumores pT1. En 41 casos no se realizó vaciamiento axilar (35 CIS y 6 pT1mic). En 4 casos existió afectación puntual de bordes (componente intraductal) que fueron sometidos a sobreimpresión radioterápica con 20Gy. Tras un seguimiento medio de 50 meses, el 91,4% están libres de enfermedad y en 12 casos (1,9%) se desconocía su estado. Se han producido 13 recidivas (2%) a nivel mamario (2 de ellas en un cuadrante distinto). Conclusiones: El estado de los bordes de resección en un factor fundamental en la cirugía conservadora del cáncer de mama. La resección del tumor debe ser suficientemente amplia e incluir el segmento mamario asiento del tumor, para asegurar un alto índice de control local, sin comprometer el resultado cosmético. El estudio histológico de los bordes de resección permite reducir significativamente la necesidad de una segunda cirugía.Introduction: Conservative surgery combined with radiotherapy is an effective treatment in many cases of breast cancer. Nevertheless this therapy is associated with a not inconsiderable number of recurrences in the remaining breast after excision (1-1.5% recurrences per year of follow-up). Material and Methods: We reviewed 641 cases of breast cancer (age average was 52.3 years (21-82) and tumour size average 1.7 cm, 3% corresponded to pT1 tumours) treated with conservative surgery combined with radiotherapy, average follow-up of 50 months. The technique consisted of segmentectomy and at least level I-II axilary dissection (excluding in situ carcinoma diagnosed since 1997, in which lymphadenectomy was not performed). Adjuvant radiotherapy was also indicated (giving a dose of 45-50 Gy to the breast, and another 15-20 Gy dose was given to tumour size). Results: In 41 cases lymphadenectomy was not performed (35 cases of Tis, and 6 pTmic). In 4 cases, 20 Gy radiotherapy was administered to the tumour excision site because of in situ carcinoma disease in the margins. During follow-up of 50 months, 91.4% of the patients were disease- free; in 12 cases we are not informed of the present status. 13 recurrences (2%) have been found, two of which were in a different quadrant. Conclusions: The status of the surgical margins is an important factor in the practice of conservative surgery. Tumour excision must be broad enough and must include the whole segment in which the tumour is located to obtain local control of the disease, maintaining an acceptable cosmetic appearance. The intraoperative study of specimen margins permits the reduction of cases in which a second operation is needed

    A Milestone in the Chemical Synthesis of Fe3O4 Nanoparticles Unreported Bulklike Properties Lead to a Remarkable Magnetic Hyperthermia

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    Among iron oxide phases, magnetite Fe3O4 is often the preferred one for nanotechnological and biomedical applications because of its high saturation magnetization and low toxicity. Although there are several synthetic routes that attempt to reach magnetite nanoparticles NPs , they are usually referred as IONPs iron oxide NPs due to the great difficulty in obtaining the monophasic and stoichiometric Fe3O4 phase. Added to this problem is the common increase of size shape polydispersity when larger NPs D gt; 20 nm are synthesized. An unequivocal correlation between a nanomaterial and its properties can only be achieved by the production of highly homogeneous systems, which, in turn, is only possible by the continuous improvement of synthesis methods. There is no doubt that solving the compositional heterogeneity of IONPs while keeping them monodisperse remains a challenge for synthetic chemistry. Herein, we present a methodical optimization of the iron oleate decomposition method to obtain Fe3O4 single nanocrystals without any trace of secondary phases and with no need of postsynthetic treatment. The average dimension of the NPs, ranging from 20 to 40 nm, has been tailored by adjusting the total volume and the boiling point of the reaction mixture. Mössbauer spectroscopy and DC magnetometry have revealed that the NPs present a perfectly stoichiometric Fe3O4 phase. The high saturation magnetization 93 2 A m2 kg at RT and the extremely sharp Verwey transition at around 120 K shown by these NPs have no precedent. Moreover, the synthesis method has been refined to obtain NPs with octahedral morphology and suitable magnetic anisotropy, which significantly improves the magnetic hyperthemia performance. The heating power of properly PEGylated nano octahedrons has been investigated by AC magnetometry, confirming that the NPs present negligible dipolar interactions, which leads to an outstanding magnetothermal efficiency that does not change when the NPs are dispersed in environments with high viscosity and ionic strength. Additionally, the heat production of the NPs within physiological media has been directly measured by calorimetry under clinically safe conditions, reasserting the excellent adequacy of the system for hyperthermia therapies. To the best of our knowledge, this is the first time that such bulklike magnetite NPs with minimal size shape polydispersity, minor agglomeration, and exceptional heating power are chemically synthesize

    Tracing of temporo-entorhinal connections in the human brain: cognitively impaired argyrophilic grain disease cases show dendritic alterations but no axonal disconnection of temporo-entorhinal association neurons

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    Argyrophilic grain disease (AGD), a neurodegenerative disorder, is often associated with mild to moderate Alzheimer’s disease (AD)-related pathology. The development of dementia in AGD is associated with the extent of coexisting AD-related pathology. Therefore, the question arises whether the degenerative changes in the neuronal network of demented AGD-patients represent a distinct pattern or show similar changes of disconnection as considered for AD. We were able to apply DiI-tracing in two human autopsy cases with mild AD-related pathology (controls), in one AD-patient, in one non-demented patient with advanced AD-related pathology, and in three cognitively impaired AGD-patients. DiI-crystals were injected into the entorhinal cortex. Pyramidal neurons of layers III and V of the adjacent temporal neocortex (area 35) were retrogradely marked with the tracer and analyzed. The AD case did not exhibit any retrogradely labeled neurons in the temporal neocortex. In the non-demented case with advanced AD-related pathology, the number of traced neurons was reduced as compared to that in the two controls and in the three AGD cases. In contrast, all three cognitively impaired AGD cases exhibited labeled pyramidal neurons in area 35 in an almost similar number as in the controls. However, alterations in the dendritic tree were observed in the AGD cases. These results show the existence of temporo-entorhinal connections in the adult human brain similar to those reported in animal models. Furthermore, the present study based on seven cases is the first attempt to study changes in the neuronal network in a human tauopathy with targeted axonal tracing techniques. Our findings in three cognitively impaired AGD cases suggest that AGD-related dementia constitutes a distinct disorder with a characteristic pattern of degeneration in the neuronal network
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