[Exploratory study of clinical reasoning in nursing students with concept mapping]. / Etude exploratoire du raisonnement clinique chez les etudiants en soins infirmiers à l'aide de la carte conceptuelle.

BACKGROUND: The training reference leading to the state nursing diploma places the learning of clinical reasoning at the center of the training. We have been wondering about the possibilities of making visible the student nurse's mental processes when they provide nursing care in order to identify their strategies and reasoning difficulties. It turns out that concept mapping is a research tool capable of showing these two aspects. OBJECTIVES: The aim of this study is to verify a concept mapping made during an interview and built from the speech of a nursing student when analyzing a simulated clinical situation, is able to make visible its strategies clinical reasoning and reasoning difficulties. In a second phase of it, is to explore how the concept map once elaborated allows students to identify their own intellectual reasoning. METHOD: 12 nursing second year students have participated in the study. Concept maps were constructed by the trainer/researcher as the students analyzed aloud a simulated clinical situation written. Concept maps were analyzed from a reference grid. Interviews were conducted following the elaboration of concept maps and student's comments were analyzed. RESULTS: Students reasoning strategies were either mixed inductive dominant (5/12) or hypothetical-deductive dominant (5/12). Reasoning difficulties identified are related to the lack of identification of important information, the lack of analysis of data, lack of connection or the existence of faulty links. Analysis of the comments highlights that concept mapping contributed to the development of metacognitive skills. CONCLUSION: The concept mapping has shown benefits in contributing to a diagnostic assessment of clinical reasoning learning. It is an additional resource tool to facilitate the development of metacognitive skills for students. This tool can be useful to implement support learning strategies in clinical reasoning.

A flavivirus protein M-derived peptide directly permeabilizes mitochondrial membranes, triggers cell death and reduces human tumor growth in nude mice.

Dengue viruses belong to the Flavivirus family and are responsible for hemorrhagic fever in Human. Dengue virus infection triggers apoptosis especially through the expression of the small membrane (M) protein. Using isolated mitochondria, we found that synthetic peptides containing the C-terminus part of the M ectodomain caused apoptosis-related mitochondrial membrane permeabilization (MMP) events. These events include matrix swelling and the dissipation of the mitochondrial transmembrane potential (DeltaPsi(m)). Protein M Flavivirus sequence alignments and helical wheel projections reveal a conserved distribution of charged residues. Moreover, when combined to the cell penetrating HIV-1 Tat peptide transduction domain (Tat-PTD), this sequence triggers a caspase-dependent cell death associated with DeltaPsi(m) loss and cytochrome c release. Mutational approaches coupled to functional screening on isolated mitochondria resulted in the selection of a protein M derived sequence containing nine residues with potent MMP-inducing properties on isolated mitochondria. A chimeric peptide composed of a Tat-PTD linked to the 9-mer entity triggers MMP and cell death. Finally, local administration of this chimeric peptide induces growth inhibition of xenograft prostate PC3 tumors in immuno-compromised mice, and significantly enhances animal survival. Together, these findings support the notion of using viral genomes as valuable sources to discover mitochondria-targeted sequences that may lead to the development of new anticancer compounds.

Regional cerebral blood flow in deficit/nondeficit types of schizophrenia according to SDS criteria.

A relationship between "hypofrontality" and a negative form of schizophrenia is commonly found. The Schedule for the Deficit Syndrome (SDS) provides specific criteria for assessing the presence of negative symptoms, their duration and whether the symptoms are primary or secondary. The purpose of our study was to compare the regional cerebral blood flow (rCBF) at rest, in 62 deficit and nondeficit schizophrenic patients, according to the SDS criteria (French version). The deficit patients in our population were comparable to those described in the literature (stability of their negative symptoms with time, poor premorbid adjustment, duration of the illness, age at the first episode, etc.). No difference was found in the locoregional perfusion with respect to the DSM-III-R type of schizophrenia, the sex or the type of treatment received. The patients with a deficit form of schizophrenia showed a significant bilateral reduction in single photon emission computed tomography (SPECT) perfusion in the right frontodorsolateral cortex (P=.0105) and the left frontodorsolateral cortex (P=.0004) compared with the nondeficit schizophrenic patients. The contribution of SDS seems to be helpful in distinguishing between significant cerebral characteristics in deficit schizophrenics, as defined by Carpenter. These results suggest a decrease in prefrontal perfusion at rest, which corresponds with neuropsychological data.

SPECT imaging, clinical features, and cognition before and after low doses of amisulpride in schizophrenic patients with the deficit syndrome.

The aim of the study was to examine the action of low-dose amisulpride (100 mg/d), an atypical antipsychotic from the benzamide class with a high affinity for the D2 and D3 dopamine receptors, given for 4 weeks in 19 schizophrenic patients with the deficit syndrome, in terms of clinical response, modifications in their cognitive performance and changes in brain perfusion values. A secondary objective was to distinguish between primary and secondary deficit, according to Carpenter's definition. Both efficacy and a relatively low rate of side effects of low-dose amisulpride in the deficit forms of schizophrenia were found as expected from earlier placebo-controlled studies. Our study found significant changes in the cerebral blood flow, before and after treatment, more marked in the frontal area and particularly in the dorso-lateral frontal area. A significant improvement of cognitive function was found after treatment, without a link to any particular changes in a loco-regional perfusion value. Finally, a distinction between primary and secondary deficit showed a higher percentage of clinical improvement in the patients with a secondary deficit. The psychometric and cerebral perfusion changes were no different in the two groups.