21 research outputs found
The influence of semantic and phonological factors on syntactic decisions: An event-related brain potential study
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
Evaluation of volume-weighted mean nuclear volume in endometrial lesions
The individual nuclear size was studied in
three groups of endometrial samples (simple hyperplasia
-SH-, atypical hyperplasia -AH-, and well-differentiated
adenocarcinoma -WDA-). The application of recent
semiquantitative systems in combination with
stereological methods permits a simple, quick and
unbiased estimation of the volume-weighted mean
nuclear volume V,(nucl). We have found an increase in
the V,(nucl) from SH to AH to WDA. There are
significant differences between the mean of the three
groups (pc0.01). The variance associated with estimates
of V,(nucl) is mainly provided by differences among
lesions; i.e. patients. This capacity for discriminating
may be associated with gland and lumen endometrial
quantification to improve the correct diagnosis of
endometrial samples
Objective differential classification of thyroid lesions by nuclear quantitative assessment
Quantitative nuclear parameters estimated by
morphometric and stereological methods in combination
with discriminant analysis were used in order to evaluate
the diagnostic efficiency of thyroid lesions. This study
includes 55 patients with thyroid pathology. Samples of
follicular adenomas, follicular carcinoma, and papillary
carcinomas were exarnined by image analysis to obtain
size and form nuclear parameters. Stepwise discriminant
analyses were performed. There was an increase in
nuclear size from follicular adenomas to follicular
carcinomas, and a greater increase from follicular
carcinomas to papillary carcinomas. The increase was
more significant when the three-dimensional estimates
of the volume-weighted mean nuclear volume were
assessed. No significant differences between follicular
adenomas and follicular carcinomas were found with
respect to the nuclear form factors; however, a
significant increase in nuclear elongation and irregularity
was registered between follicular and papillary tumors
(pe0.01). The overall accuracy rate of discrimination
was 75% when the three lesions were included in the
analysis, with an efficiency of 85% for papillary
carcinoma samples. These percentages increased when
two lesion discrimination was performed. The worst
discrimination (69% of efficiency) was found between
follicular adenomas and follicular carcinomas
Multivariate discriminant analysis of normal, intraepithelial neoplasia and human papillomavirus infection of the uterine cervix samples
The present investigation studies the role of
multivariate statistical methods on quantitative
histopathological features of cells in uterine cervix
epithelium to discriminate between normal and abnormal
uterine cervix samples. 143 histological specimens were
included in the study involving normal cervix, cervical
intraepithelial neoplasia (CIN) lesions and cervical
human papillomavirus (HPV) infection with and without
CIN (condyloma-CIN and condyloma-NCIN
groups, respectively). Deep, middle and superficial
regions of the cervical squamous epithelium were
morphometrically analyzed. Identification of normal
cervix from pathological cases was highly achieved with
a specificity of 100%. The application of discriminant
statistical method within pathological specimens showed
an acceptable percentage of cases correctly classified;
thus, an efficiency of 83.0% and 74.6% was obtained in
order to discriminate within CIN and condyloma-CIN
grades respectively. These percentages increased when
differentiation between each grade of CIN versus
condyloma-CIN were considered, using only 1-3
morphometrical parameters. Our findings indicate that
the combination of nuclear and cytoplasmic quantitative
features, specially size parameters, permit a high correct
percentage classification of cervix samples. The
discrimination process was better when few diagnostic
categories were included; however, 100% specificity for
normal samples was always reached
Self-directed learning in the Gross Anatomy medical curriculum.
The Medical School of the University of Castilla- La Mancha (UCLM) in Albacete is the most recent School of Medicine approved in Spain. The Institution was launched in the academic year 1998- 99 with the specific aim of implementing educational innovations in the medical curriculum. The ultimate goal is to provide future doctors with the competences and skills for medical practice among the people of the region of Castilla- La Mancha, and Spanish society in general, by providing the means for easy integration into the job market of our society. The medical curriculum at UCLM, as in any other medical school in the country, is six years long and is divided into a basic sciences part (first to third years) and clinical sciences part (fourth to sixth years). The teaching method of the UCLM Medical School departs from most Medical Schools in Spain by incorporating the most recent educational trends and technological advances, lead and directed by a Medical Education Unit. The UCLM Medical School organizes its medical curriculum according to two different, but not mutually exclusive, educational approaches: 1. self-directed learning, organized in modules of objectives (basic sciences), and 2. problem-based learning (PBL, for the clinical sciences). The ultimate goal of the curriculum is an integration of basic and clinical disciplines, both among courses in each year of the medical curriculum and among the different years of the degree at both the preclinical and clinical levels. Likewise, maximal interaction between Faculty and students is strongly encouraged, and indeed facilitated by restricting the number of new students per year to a maximum number of 80, divided into four groups of 20 students (basic sciences), and 6 students in the clinical sciences. Gross Anatomy courses are given in the first and second years. During the first year, the locomotor system is presented as a 10-credit course (one credit equals 10 hours of teaching activity). During the second year, Anatomy and Embryology are integrated as a single course, along with Physiology and Histology, comprising 70 credits altogether. In both instances, the contents are organized into modules of objectives two to three weeks long. Each module is divided into five phases. Phase 1 includes an introduction to the objectives and its resources (books, anatomical CD programs, and other educational material), in order to help the student to accomplish the objectives. Phase 2 is a self-learning period, followed by Phase 3, in which the students expound on and discuss the contents related to the objectives. Phase 4 is another period for self-learning and tutorials, while Phase 5 is the evaluation of individual or several thematically related modules. In Gross Anatomy, practical courses are interwoven in the modules in phases 2 and 4. In addition, this past year we have introduced 4 lectures per year in which the students attend to more general and clinical aspects of several modules of objectives. It is important to point out that in addition to the regular practical hours and learning periods, students carry out two gross anatomical dissections per year with the help of handouts and other reference material, after which they present a written report that is a percentage of the final score. Throughout the program, both the autonomy and interests of the students are emphasized. Here, preliminary theoretical and practical results will be discussed
Hippocampal Formation Projection To Ventral Tegmental Area: An Anatomical Study In The Non-Human Primate
The Hippocampal Formation (HF) has a critical role in episodic memory. One of the major components in episodic memory is the encoding of novel stimuli, which is associated to dopaminergic system. Lisman and Grace (2005) proposed that novelty signals in the hippocampus modulate the activity of dopaminergic neurons in the ventral tegmental area (VTA) and that, via a feedback loop, the increase of dopamine in hippocampal neurons promotes the encoding for the novel event. Retrograde tracer studies have demonstrated that the VTA projects directly to the HF in primates (Amaral and Cowan, 1980; Insausti et al., 1987) as well as in rodents. However, whether these projections are reciprocal or not is unknown. Despite this lack of evidence of a direct projection, functional studies indicate that the dopaminergic neurons of the VTA are strongly influenced by the hippocampus indirectly through either lateral septum (Luo et al. 2011) or nucleus accumbens-ventral pallidum pathways (Lisman and Grace 2005). In order to determine the existence of direct inputs from the HF to the VTA and which are the specific fields within the HF responsible of the projection, the retrograde tracers were placed in the mesencephalic ventral and dorsal tegmentum of the Macaca fascicularis monkey, including the VTA. The retrograde cell labeling was analyzed with an epifluorescence microscope coupled to a computerized charting system. Our preliminary results showed scarce labeled cells in the HF, specifically in dorsal subiculum, and deep layers of the caudomedial portion of the entorhinal cortex (subfield EO and medialmost EI). These results clarify the functional HF-VTA loop playing a role in learning and memory, and different neuropsychiatric diseases (schizophrenia, Alzheimer´s and Parkinson's disease
Postnatal development of calcium-binding proteins immunoreactivity (parvalbumin, calbindin, calretinin) in the human entorhinal cortex
The entorhinal cortex is an essential component in the organization of the human hippocampal formation related to cortical activity. It transfers, neocortical information (ultimately distributed to the dentate gyrus and hippocampus) and receives most of the hippocampal output directed to neocortex. At birth, the human entorhinal cortex presents similar layer organization as in adults, although layer II (cell islands) and upper layer III have a protracted maturation. The presence of interneurons expressing calcium-binding proteins (parvalbumin, calbindin–D28K (calbindin) and calretinin) is well documented in the adult human entorhinal cortex. In many of them the calcium binding is co-localized with GABA. Parvalbumin-immunoreactive cells and fibers were virtually absent at birth, their presence increasing gradually in deep layer III, mostly in the lateral and caudal portions of the entorhinal cortex from the 5th month onwards. Calbindin immunoreactive cells and fibers were present at birth, mainly in layers II and upper III; mostly at rostral and lateral portions of the entorhinal cortex, increasing in number and extending to deep layers from the 5th month onwards. Calretinin immunoreactivity was present at birth, homogeneously distributed over layers I, II and upper V, throughout the entorhinal cortex. A substantial increase in the number of calretinin neurons in layer V was observed at the 5th month. The postnatal development of parvalbumin, calbindin and calretinin may have an important role in the functional maturation of the entorhinal cortex through the control of hippocampal, cortical and subcortical information