Behavioral and functional neuroanatomical correlates of anterograde autobiographical memory in isolated retrograde amnesic patient M.L.

Patient M.L. [Levine, B., Black, S. E., Cabeza, R., Sinden, M., Mcintosh, A. R., Toth, J. P., et al. (1998). Episodic memory and the self in a case of isolated retrograde amnesia. Brain, 121, 1951-1973], lost memory for events occurring before his severe traumatic brain injury, yet his anterograde (post-injury) learning and memory appeared intact, a syndrome known as isolated or focal retrograde amnesia. Studies with M.L. demonstrated a dissociation between episodic and semantic memory. His retrograde amnesia was specific to episodic autobiographical memory. Convergent behavioral and functional imaging data suggested that his anterograde memory, while appearing normal, was accomplished with reduced autonoetic awareness (awareness of the self as a continuous entity across time that is a crucial element of episodic memory). While previous research on M.L. focused on anterograde memory of laboratory stimuli, in this study, M.L.’s autobiographical memory for post-injury events or anterograde autobiographical memory was examined using prospective collection of autobiographical events via audio diary with detailed behavioral and functional neuroanatomical analysis. Consistent with his reports of subjective disconnection from post-injury autobiographical events, M.L. assigned fewer “remember” ratings to his autobiographical events than comparison subjects. His generation of event-specific details using the Autobiographical Interview [Levine, B., Svoboda, E., Hay, J., Winocur, G., & Moscovitch, M. (2002). Aging and autobiographical memory: dissociating episodic from semantic retrieval. Psychology and Aging, 17, 677-689] was low, but not significantly so, suggesting that it is possible to generate episodic-like details even when re-experiencing of those details is compromised. While listening to the autobiographical audio diary segments, M.L. showed reduced activation relative to comparison subjects in midline frontal and posterior nodes previously identified as part of the autobiographical memory network. Reductions were also evident in M.L. in association with personal semantic stimuli (e.g., recordings describing personal habits and routines). These data suggest an association between M.L.’s impoverished recollection of autobiographical material and reduced activation in midline sectors of the autobiographical memory network that support the autonoetic, first-person element of episodic memory.     

Effects of childhood trauma on HPA-axis reactivity in women free of lifetime psychopathology

Exposure to childhood trauma may induce persistent changes in Hypothalamic-Pituitary-Adrenal (HPA)-axis functioning even in the absence of current psychopathology. Because previous studies did not systematically exclude subjects with lifetime psychiatric morbidity, prevalent psychopathology may have confounded the association. In this study we investigated whether women exposed to childhood trauma, but without a history of psychiatric disorders, show alterations in HPA-axis functioning. We included 10 women exposed to significant childhood trauma and 12 non-exposed women. All women were between 29 and 64 years old, mentally and physically healthy, and without current or lifetime psychopathology. HPA-axis functioning was assessed as 1) basal activity with salivary cortisol patterns over 8 time points on two consecutive sampling days and 2) plasma cortisol and adrenocorticotropic hormone (ACTH) reactivity over 7 time points after the combined dexamethasone/corticotropin-releasing hormone (dex/CRH) challenge test. Basal salivary cortisol output did not differ between trauma-exposed compared to non-exposed women. Significantly blunted plasma cortisol and ACTH responses in response to dex/CRH administration were found in the trauma-exposed compared to the non-exposed women (F(1,20) = 5.08, p = 0.04 and F(1,20) = 5.23, p = 0.03 respectively). Adjusting for age, body mass index (BMI), oral contraceptive use, and menopausal status, somewhat weakened the associations for cortisol as well as ACTH (F(1,16) = 3.30, p = 0.09) and F(1,16) = 2.17, p = 0.16 respectively), but for cortisol absolute differences in point estimates were largely unaffected. Although basal cortisol patterns were similar in the two groups, exposure to childhood trauma seemed to be related to a blunted HPA-axis reactivity in women who were free of current or lifetime psychopathology.     

Do schizophrenia and bipolar disorders share a common disease susceptibility variant at the MMP3 gene?

There is growing evidence of partial etiological overlap between schizophrenia (SZ) and bipolar I disorder (BD-I) from linkage analysis, genetic epidemiology and molecular genetics studies. SZ and BD-I are neurodevelopmental disorders with genetic and environmental etiologies. Recent studies have demonstrated that matrix metalloproteinase 3 (MMP3) is a key event in associative memory formation, learning and synaptic plasticity, which are important in psychiatric disorders. In the light of these findings, we analyzed the genetic variations in the MMP3-1171 5A/6A in patients with SZ, patients with BD-I and healthy controls. To the best of our knowledge, this is the first study to report an association of variation in gene encoding MMP3 with SZ. Our study group consisted of 111 unrelated patients with SZ, 141 unrelated patients with BD-I, and 121 unrelated healthy controls. The frequencies of 6A6A genotype and 6A allele distributions of MMP3 in patients with SZ were significantly decreased when compared with controls. In contrast, in patients with SZ, the distributions of 5A5A genotype and 5A allele of MMP3 gene were significantly increased as compared with healthy controls. When the frequencies of genotypes or alleles in schizophrenic patients and bipolar patients were compared, 6A6A genotype and 6A allele in patients with BD-I were significantly higher than patients with SZ. In contrast, 5A5A genotype and 5A allele distributions of MMP3 gene were significantly frequent in patients with SZ. On the other hand, no significant differences were found in the allele or genotype distribution in patients with BD-I compared with controls. In conclusion, our data have supported the hypothesis that there is a possible relationship between − 1171 5A/6A polymorphism of MMP3 gene and SZ. A larger sample group is needed to confirm the potential role of this gene in the pathophysiology of psychiatric disorders.     

Body mass index in male Caucasian veterans with or without posttraumatic stress disorder

Obesity (defined as body mass index (BMI) higher than 30), is a serious and global public health problem, associated with increased morbidity and mortality and it represents a risk factor for developing various somatic and psychiatric disorders. Combat-related posttraumatic stress disorder (PTSD) is frequently associated with increased BMI which leads to overweight and obesity. We therefore evaluated BMI in the ethnically uniform Croatian male participants of the Caucasian origin, combat exposed veterans with or without PTSD, controlled for the effect of trauma, age, smoking, alcohol consumption, physical activity and comorbid psychiatric disorders, and in age matched healthy control subjects. BMI did not differ significantly between veterans with or without PTSD and healthy control subjects, or when participants were subdivided according to the age groups, BMI categories, or the presence of psychiatric disorders. Limitation of the study might be a small number of veterans with or without PTSD. Similar BMI was found in Croatian male veterans with or without PTSD, and age matched healthy control subjects. The data provided evidence of overweight and obesity in large number of veterans but also in healthy control subjects, and indicated that public health organizations should develop more effective strategies to prevent overweight and obesity.     

Diagnostic specificity of the insular cortex abnormalities in first-episode psychotic disorders

Volume reductions of the insular cortex have been described in schizophrenia, but it remains unclear whether other psychotic disorders such as affective psychosis also exhibit insular cortex abnormalities. In this study, we used magnetic resonance imaging to investigate the gray matter volume of the anterior (short) and posterior (long) insular cortices in 162 first-episode patients with various psychotic disorders (46 schizophrenia, 57 schizophreniform disorder, 34 affective psychosis, and 25 other psychoses) and 62 age- and gender-matched healthy comparison subjects. Patients with schizophrenia showed bilateral volume reduction of the anterior and posterior insular cortices compared with controls, but the remaining first-episode psychosis subgroups had normal insular volumes. The volumes of these insular subregions were significantly smaller in schizophrenia patients than in patients with schizophreniform disorder or affective psychoses. There was no association between the insular cortex volume and daily dosage or type of antipsychotic medication in any patient group. These findings suggest that the widespread volume reduction of the insular cortex is specific to established schizophrenia, implicating its role in the neurobiology of clinical characteristics associated with schizophrenia.     

Fatigue after stroke: the development and evaluation of a case definition

OBJECTIVE: While fatigue after stroke is a common problem, it has no generally accepted definition. Our aim was to develop a case definition for post-stroke fatigue and to test its psychometric properties. METHODS: A case definition with face validity and an associated structured interview was constructed. After initial piloting, the feasibility, reliability (test-retest and inter-rater) and concurrent validity (in relation to four fatigue severity scales) were determined in 55 patients with stroke. RESULTS: All participating patients provided satisfactory answers to all the case definition probe questions demonstrating its feasibility For test-retest reliability, kappa was 0.78 (95% CI, 0.57-0.94, P<.01) and for inter-rater reliability kappa was 0.80 (95% CI, 0.62-0.99, P<.01). Patients fulfilling the case definition also had substantially higher fatigue scores on four fatigue severity scales (P<.001) indicating concurrent validity. CONCLUSION: The proposed case definition is feasible to administer and reliable in practice, and there is evidence of concurrent validity. It requires further evaluation in different settings.     

Cannabis induces different cognitive changes in schizophrenic patients and in healthy controls

It is known that 60 to 80% of schizophrenic patients show deficits in cognition. There may be an increase in these deficits as a result of additional regular use of cannabis. The aim of the study was to evaluate the effect of chronic cannabis consumption on the cognitive functions of schizophrenic patients and healthy control subjects after a minimum abstinence time of 28 days. The study sample consisted of 39 schizophrenics (19 cannabis-abusers and 20 non-abusers) and 39 healthy controls (18 cannabis-abusers, 21 non-abusers). In a 2x2-factorial design (Diagnostic Groups [healthy controls, schizophrenic patients]xCannabis abuse [without, with]) with diagnostic group and cannabis consumption considered between-subject factors) we tested the hypothesis that dually diagnosed patients (i.e. suffering both from schizophrenia and cannabis abuse) perform worse in neuropsychological tests than schizophrenic patients without cannabis abuse. On the whole, schizophrenic patients performed worse than healthy control subjects. Surprisingly, rather than deteriorating neuropsychological performance, regular cannabis abuse prior to the first psychotic episode improved cognition in some tests. This was even more pronounced when regular consumption started before the age of 17. On the other hand, cannabis use deteriorated test performance in healthy controls, especially in cases when regular consumption started before the age of 17. To sum up, regular cannabis abuse has a different effect on cognitive function in schizophrenic patients and healthy controls.     

Association between the MnSOD Ala-9Val polymorphism and development of schizophrenia and abnormal involuntary movements in the Xhosa population

Reactive oxygen species (ROS)-mediated damage has been hypothesized to play a role in the development and poor outcome of schizophrenia, as well as the development of neuroleptic-induced abnormal involuntary movements. Recently, the functional polymorphism (Ala-9Val) in the manganese superoxide dismutase (MnSOD) gene (part of the antioxidant defense mechanism) was found to be associated with schizophrenia in a Turkish population. This study was aimed at replicating this finding in a Xhosa population. In addition, the role of Ala-9Val in abnormal involuntary movement and tardive dyskinesia development in the Xhosa population was also investigated. The schizophrenic patient group (n=286) and a healthy control group (n=243) were genotyped for the Ala-9Val polymorphism using heteroduplex-single stranded conformational polymorphism (HEX-SSCP) analysis. No significant difference in genotype or allele frequency could be observed between the schizophrenia and control group (P=0.294 and P=0.528 respectively). In addition no association could be found between the polymorphism and symptom severity (SANS and SAPS). The Xhosa schizophrenia patient group with abnormal involuntary movements (n=54) and a subgroup with tardive dyskinesia (n=30) was found to significantly differ in Ala-9Val genotype frequency (P=0.008 and P=0.011 respectively) compared to the Xhosa schizophrenia patient group without abnormal involuntary movements (n=204). However, no significant difference was found for the allele frequencies (P=0.955 and P=0.161). Further, using ANCOVA no association was found between AIMS score and genotype in the group with abnormal involuntary movements (P=0.1234). However, in the patient group with tardive dyskinesia an association was observed between genotype and AIMS score (P=0.0365). These results do not support a major role of the MnSOD Ala-9Val polymorphism in the development of schizophrenia or symptom severity in the Xhosa population. Yet it seems to be involved in the development of abnormal involuntary movements and tardive dyskinesia and may even modulate the severity of tardive dyskinesia.     

新入伍士兵自杀意念与自杀行为影响因素调查

目的调查分析影响新入伍士兵自杀意念与自杀行为的主要因素,为自杀预防干预提供依据。方法采取随机整群抽样的方式对5345名官兵使用SCL-90问卷筛查,对筛查阳性者再实施半结构式访谈定性,确认自杀意念形成的主要相关因素。结果存在不同程度自杀意念者共171人,占调查人数的3.1%,其中13人有过对有关实施方式的计划。自杀意念和行为形成的因素中,家庭因素影响较多,主要是家庭关系、家族史、家庭经济等。结论新入伍士兵自杀意念和自杀行为形成过程中,家庭是重要的因素,进行预防性自杀干预时,应对其家庭因素给予充分的关注。     

基层医疗机构负责人对零差率基本药物政策的短期效果评价

目的 了解我国零差率基本药物政策实施的短期效果和存在问题,提出政策建议.方法 对福建省某市参与基本药物零差率试点12家基层医疗机构的负责人进行访谈,采用频数统计和文字归纳整理资料.结果 被访谈者认为,零差率基本药物政策有利于改善居民用药的经济可及性,但短期内难以达到规范临床用药行为的目的.结论 要适时、科学地调整<基本药物目录>,完善财政补偿机制,实现政策同步推进,以促进国家基本药物制度的可持续发展.