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Social Psychiatry and Psychiatric Epidemiology - The negative effect of catastrophic financial loss on suicide risk is widely perceived but hardly studied in-depth because of various difficulties...  相似文献   
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ObjectivesTrauma appears within the discourse of mentally injured people, materializing what we have recently defined as “post traumatic psycholinguistic syndrome” (SPLIT). Translating unspeakability, revival, and dissociation, this clinical entity associates three significant disturbances : traumatic anomia (missing words, reduction of the elocutionary flow, deictic gestures, etc.); linguistic repetitions (of words and phrases, verbal intrusions, echophrasias, etc.); and phrasal and discursive disorganization (incomplete sentences, tense discordance, dysfluence, lack of logical connectors, etc.). What are the causes of these semiological and psycholinguistic expressions? What are their psychological and/or neuropsychological processes? It is time to come up with a new concept intended to go beyond the previous models in order to better identify people suffering from post-traumatic mental disorders, to better organize and evaluate psychotherapeutic care, and also to help practitioners collaborate more effectively on these first two goals. But how to evoke, affirm, or speak out about the consequences of unspeakability? Nothing is more apparently contradictory than wanting to define the language void. How to account for the fractures of psychic trauma in discourse? Nothing is more uncertain than to try to organize the upheavals, the disorders caused by dissociation in language. Finally, how to specify the reiteration of the trauma using words and sentences without this modeling being dissociative or repetitive? Today, thanks to a psycholinguistic reading, essential dimensions of post-traumatic suffering, hitherto hidden, can be clarified. Why exactly does an event cause trauma in the life of a subject at a given moment in her/his existence? Why is a latency phase structured between the traumatic event and the return of reviviscences under the influence of a re-triggering factor? How to differentiate the notion of dissociation as a normal phenomenon from the so-called traumatic dissociation? How to explain the multiple clinical forms of post-traumatic psychological disorders?MethodsFrom Pierre's clinical history, we chronologically detail the structuring and the consequences of the signified reflection that are constitutive of the psychic trauma: the psycholinguistic tools here help to formulate a new etiopathogenic conception of trauma and its psychological consequences. Then, thanks to Jean's testimony, taking up the retrospective meaning of the clinical analysis from chronic repetition syndrome, we discover the phases of tension regarding signified knowledge, up to the network prior to the traumatic confrontation. Finally, illustrated by Karima's disorder, beyond depersonalization, we explain that the analysis of the disturbances of a singular signified network, and also of an attack on its familial and societal bases, testifies to individual and collective subjectivities.ResultsComing from the real world, and therefore also from the body, the stimuli made up of signals picked up by our senses combine to compose an event that can be objectified by its temporal, spatial, biological, and physico-chemical coordinates. These elements combine into a unit, which is then interpreted by the mind, which attributes meaning to this event, which has become subjective reality. But when the subject is not sufficiently prepared to be confronted with this meaning that appears to be in extreme contradiction with her/his previous cardinal networks of significations, it makes “too much sense:” this irreconcilable hyper-signified (that we call the traumatic signified) results in post-traumatic dissociation. In other words, it is an impossibility of concordance of a signified with certain systems of prior significations that constitutes the pathogenesis of the trauma; and a situation runs a greater risk of being traumatic when it contradicts, or, moreso, endangers some or all of the subject's cardinal meanings. This unbearable signified reflexively blocks the capacities of significations immediately pre- and post-trauma, then dissociates the psychic functions to varying degrees and intensities. The traumatic signified, rejected, becomes unattainable: the stimuli that led to its formation find themselves confined to the state of reviviscences, each replication of which attempts to cross the barrier of inconceivability. Limiting sensory compounds to their raw states without the possibility of representational integration, associative pathways remain blocked. The signifier is referred to a hypo-signifier confined to the infra-linguistic by its confusion with the referent, the “objective and material” components of the traumatic event. Dissociation is therefore only a symptomatic reaction, secondary to the trauma, which it reinforces once again by limiting any possibility of representing the trauma. This dissociation does not involve forgetting the traumatic signified but “protects” the adjacent networks of meanings from it as much as it “keeps” this hypersignified intact, therefore ultimately “protecting” it as well. The traumatic signified persists somewhere, and even ends up being found everywhere: when the networks of meanings turn out to be globally disturbed, the tightest links remain those of the traumatic hypersignified that ultimately governs all the networks of meanings.DiscussionOur insufficient knowledge prevents us from precisely qualifying the architecture of the signified idiosyncratic networks and their evolutionary capacities; we cannot predict, beforehand, the reaction of an individual confronted with a potentially psychotraumatic situation. For most clinical situations, we affirm that the psychological trauma occurs in a psychically healthy subject, that is, not suffering from any psychiatric illness or any obvious psychopathological conflict. Psychotherapy will make it possible to discover the signified, sometimes ancient, origins of a trauma occurring in a singular subject. How was this subjectivity constructed? Beyond individual subjectivity, the intensity of certain confrontations such as serious attacks or macrosocial catastrophes such as genocide, would seem to lead to psychological wounds in any individual, even at the scale of a population. While, throughout existence, each subject produces a system of significations in connection with a unique psychic construction, the latter persists – resulting from, and often remaining overseen by, the community essence of a base of signifying networks, which we call “societal subjectivity.” Here, the psychological trauma can correspond to an individual and “common” injury as a failure of a sharing, or of ancestral beliefs anchored in the collective memory, defining the culture. By the collapse of acquired certainties, the cognitive patterns transmitted by education, language, and everything that establishes one's belonging to a society, trauma shakes the networks of individual and group meanings. Horror has a higher traumatogenic risk, because it defeats the fundamentals of humankind, the foundations of a signified network common to a culture, or even to all cultures, to the human condition. This is the case with murder, rape, torture, wars, genocides. Testifying to an instinct for survival stemming from the biological foundations of every living being, the impossibility of “living death” appears to be anchored in our networks of meanings and is manifested by indescribability, traumatic as such: being deserted by the language collides with the condition of speaking. And yet, it remains possible to say something about it... As a path of progressive desocialization, the occasional loss of the community of language, followed by its lasting traumatic ravages, can be appeased by the reestablishment of a speech link, either within the mind of the subject alone, or promoted by the exchange with others, in a psychotherapeutic setting, for example.ConclusionWhere theoretical discourses have sometimes proved divisive, going beyond the symptoms of indescribability and dissociation, psychodynamic practice today offers to unite. Thanks to psycholinguistic listening, phenomena that have never been explained take on meaning: the singularity of traumatic perception, the chronology of disorders including the latency phase, factors that trigger reviviscences, and the diversity of chronic clinical forms. All these post-traumatic symptoms are consequential to a linguistic wound, a difficulty in accessing meaning, the undermining of two dimensions characterizing and constructing the human being. As much as it integrates extralinguistic determinants, if the traumatic signified is undoubtedly not only speech, language appears the optimal way to identify it as such, while in the same movement appeasing it. The traumatic hypersignified is discovered through clinical analysis and psychotherapy, through deferred action, through the attribution of meaning, through the retrospective reconstruction of an unstable “real,” through a changing narration eternally distancing itself from reviviscences. But what precisely are the mechanisms of effective therapies ? What are the intersubjective links called for in the discussion between patient and practitioner? Could the operations that we call “psychotherapy” be made up of mobilizations of the networks of meanings by speech acts?  相似文献   
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Amacrine cells of the retina are conspicuously variable in their morphologies, their population demographics, and their ensuing functions. Vesicular glutamate transporter 3 (VGluT3) amacrine cells are a recently characterized type of amacrine cell exhibiting local dendritic autonomy. The present analysis has examined three features of this VGluT3 population, including their density, local distribution, and dendritic spread, to discern the extent to which these are interrelated, using male and female mice. We first demonstrate that Bax-mediated cell death transforms the mosaic of VGluT3 cells from a random distribution into a regular mosaic. We subsequently examine the relationship between cell density and mosaic regularity across recombinant inbred strains of mice, finding that, although both traits vary across the strains, they exhibit minimal covariation. Other genetic determinants must therefore contribute independently to final cell number and to mosaic order. Using a conditional KO approach, we further demonstrate that Bax acts via the bipolar cell population, rather than cell-intrinsically, to control VGluT3 cell number. Finally, we consider the relationship between the dendritic arbors of single VGluT3 cells and the distribution of their homotypic neighbors. Dendritic field area was found to be independent of Voronoi domain area, while dendritic coverage of single cells was not conserved, simply increasing with the size of the dendritic field. Bax-KO retinas exhibited a threefold increase in dendritic coverage. Each cell, however, contributed less dendrites at each depth within the plexus, intermingling their processes with those of neighboring cells to approximate a constant volumetric density, yielding a uniformity in process coverage across the population.SIGNIFICANCE STATEMENT Different types of retinal neuron spread their processes across the surface of the retina to achieve a degree of dendritic coverage that is characteristic of each type. Many of these types achieve a constant coverage by varying their dendritic field area inversely with the local density of like-type neighbors. Here we report a population of retinal amacrine cells that do not develop dendritic arbors in relation to the spatial positioning of such homotypic neighbors; rather, this cell type modulates the extent of its dendritic branching when faced with a variable number of overlapping dendritic fields to approximate a uniformity in dendritic density across the retina.  相似文献   
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Comprehensive evidence regarding the treatment of non-anaemic iron deficiency in patients undergoing valvular heart surgery is lacking. This study aimed to investigate the association between non-anaemic iron deficiency and postoperative outcomes in these patients. We retrospectively analysed 321 patients of which 180 (56%) had iron deficiency (defined as serum ferritin < 100 ng.ml-1 or < 300 ng.ml-1 with transferrin saturation < 20%). While the iron-deficient group had lower pre-operative haemoglobin levels than the non-iron deficient group (median (IQR [range]) 134 (127–141 [120–172]) g.l-1, 143 (133–150 [120–179]) g.l-1, p = 0.001), there was no between-group difference in allogeneic red blood cell transfusion. Median (IQR [range]) days alive and out of hospital at postoperative day 90 was 1 day shorter in the iron-deficient group (80 (77–82 [9–85]) days vs. 81 (79–83 [0–85]) days, p = 0.026). In multivariable analysis, only cardiopulmonary bypass duration (p = 0.032) and intra-operative allogeneic red blood cell transfusion (p = 0.011) were significantly associated with reduced days alive and out of hospital at postoperative day 90. Iron deficiency did not exert any adverse influence on secondary outcomes except length of hospital stay. Our findings indicate that non-anaemic iron deficiency alone is not associated with adverse effects in patients undergoing valvular heart surgery when it does not translate into an increased risk of allogeneic transfusion.  相似文献   
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Background

Hyperglycaemia is common in patients with acute brain injury admitted to an intensive care unit (ICU). Many studies have found associations between development of hyperglycaemia and increased mortality in hospitalised patients. However, the optimal target for blood glucose control is unknown. We want to conduct a systematic review with meta-analysis and trial sequential analysis to explore the beneficial and harmful effects of restrictive versus liberal glucose control on patient outcomes in adults with severe acute brain injury.

Methods

We will systematically search medical databases including CENTRAL, Embase, MEDLINE and trial registries. We will search the following websites for ongoing or unpublished trials: http://www.controlled-trials.com/ , http://www.clinicaltrials.gov/ , www.eudraCT.com , http://centerwatch.com/ , The Cochrane Library's CENTRAL, PubMed, EMBASE, Science Citation Index Expanded and CINAHL. Two authors will independently review and select trials and extract data. We will include randomised trials comparing levels of glucose control in our analyses and observational studies will be included to address potential harms. The primary outcomes are defined as all-cause mortality, functional outcome and health-related quality of life. Secondary outcomes include serious adverse events including hypoglycaemia, length of ICU stay and duration of mechanical ventilation, and explorative outcomes including intracranial pressure and infection. Trial Sequential Analysis will be used to investigate the risk of type I error due to repetitive testing and to further explore imprecision. Quality of trials will be evaluated using the Cochrane Risk of Bias tool, and quality of evidence will be assessed using the Grading of Recommendations, Assessment, Development and Evaluations (GRADE) approach.

Discussion

The results of the systematic review will be disseminated through peer-reviewed publication. With the review, we hope to inform future randomised clinical trials and improve clinical practice.  相似文献   
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Post-induction hypotension is common and associated with postoperative complications. We hypothesised that pneumatic leg compression reduces post-induction hypotension in elderly patients undergoing robot-assisted laparoscopic prostatectomy. In this double-blind randomised study, patients were allocated randomly to the pneumatic leg compression group (n = 50) or control (n = 50). In the intervention group, pneumatic leg compression was initiated before induction of anaesthesia. In the control group, pneumatic leg compression was initiated 20 min after anaesthesia induction. The primary outcome was the incidence of post-induction hypotension in these groups. Post-induction hypotension was defined as systolic blood pressure < 90 mmHg during the first 20 min after induction. Haemodynamic variables and area under the curve of post-induction systolic blood pressure over time were assessed. Complications associated with pneumatic leg compression were recorded, including: peripheral neuropathy; compartment syndrome; extensive bullae beneath the leg sleeves; and pulmonary thromboembolism. The incidence of post-induction hypotension decreased in the pneumatic leg compression group compared with that in the control group; 5 (10%) vs. 29 (58%), respectively, p < 0.001. In the pneumatic leg compression group, the lowest systolic, diastolic and mean blood pressures 20 min after induction of anaesthesia were significantly greater than the control group. Pneumatic leg compression resulted in an increased area under the curve of systolic blood pressure in the first 20 min after induction, p = 0.001. There were no pneumatic leg compression-related complications. Pneumatic leg compression reduced post-induction hypotension in elderly patients undergoing robot-assisted laparoscopic prostatectomy, suggesting that it is an effective and safe intervention to prevent post-induction hypotension among elderly patients undergoing general anaesthesia.  相似文献   
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