Altered intrinsic functional brain architecture in female patients with bulimia nervosa.

BACKGROUND: Bulimia nervosa is a severe psychiatric syndrome with uncertain pathogenesis. Neural systems involved in sensorimotor and visual processing, reward and impulsive control may contribute to the binge eating and purging behaviours characterizing bulimia nervosa. However, little is known about the alterations of functional organization of whole brain networks in individuals with this disorder. METHODS: We used resting-state functional MRI and graph theory to characterize functional brain networks of unmedicated women with bulimia nervosa and healthy women. RESULTS: We included 44 unmedicated women with bulimia nervosa and 44 healthy women in our analyses. Women with bulimia nervosa showed increased clustering coefficient and path length compared with control women. The nodal strength in patients with the disorder was higher in the sensorimotor and visual regions as well as the precuneus, but lower in several subcortical regions, such as the hippocampus, parahippocampal gyrus and orbitofrontal cortex. Patients also showed hyperconnectivity primarily involving sensorimotor and unimodal visual association regions, but hypoconnectivity involving subcortical (striatum, thalamus), limbic (amygdala, hippocampus) and paralimbic (orbitofrontal cortex, parahippocampal gyrus) regions. The topological aberrations correlated significantly with scores of bulimia and drive for thinness and with body mass index. LIMITATIONS: We reruited patients with only acute bulimia nervosa, so it is unclear whether the topological abnormalities comprise vulnerability markers for the disorder developing or the changes associated with illness state. CONCLUSION: Our findings show altered intrinsic functional brain architecture, specifically abnormal global and local efficiency, as well as nodal- and network-level connectivity across sensorimotor, visual, subcortical and limbic systems in women with bulimia nervosa, suggesting that it is a disorder of dysfunctional integration among large-scale distributed brain regions. These abnormalities contribute to more comprehensive understanding of the neural mechanism underlying pathological eating and body perception in women with bulimia nervosa.

Down-regulation of Bcl-XL by RNA interference suppresses cell growth and induces apoptosis in human esophageal cancer cells.

AIM: To determine the inhibitory effect of the vector-generated small interfering RNAs (siRNAs) on the expression of the Bcl-X(L) gene in established human esophageal cancer cells, and to investigate the effect of the Bcl-X(L) siRNAs on cell growth and apoptosis in esophageal cancer cells. METHODS: Three siRNA-expressing vectors targeting different sites of the Bcl-X(L) gene were constructed from pTZ-U6+1 vector. Cultured esophageal cancer cells were transfected with the siRNA-expressing vector (or the control vector) using lipofectamine 2000. Bcl-X(L) gene expression was determined with semiquantitative RT-PCR assay and Western blotting. Among the three siRNA-expressing vectors, the most highly functional vector and its effect on cell growth and apoptosis in esophageal cancer cells was further analyzed. RESULTS: Of the three siRNA-expressing vectors, siRNA-expressing vector No.1 was the most potent one which suppressed Bcl-X(L) mRNA production to 32.5% of that in the untreated esophageal cancer cells. Western blotting analysis showed that siRNA-expressing vector No.1 markedly down-regulated the expression of Bcl-X(L) in human esophageal cancer cells. Treatment of esophageal cancer cells with siRNA-expressing vector No.1 resulted in inhibition of cell growth and induction of apoptosis. CONCLUSION: Down-regulation of Bcl-X(L) by vector-generated small interfering RNAs can suppress cell growth and induce apoptosis in human esophageal cancer cells.

Analysis of clinical characteristics of dyspeptic symptoms in Shanghai patients.

OBJECTIVE: To improve the management of dyspepsia by analyzing the clinical characteristics of dyspeptic symptoms in patients from Shanghai. METHODS: 782 patients with functional dyspepsia (FD) or organic dyspepsia (OD) completed a questionnaire about dyspepsia. The questionnaire asked participants to score 12 previously validated common upper abdominal symptoms. The clinical characteristics of dyspepsia including severe symptoms; and the relationship between symptoms and meals were then analyzed. RESULTS: Among the 782 dyspeptic patients, 543 cases (69.4%) were classed as FD and 239 (30.6%) OD. The proportion of males was significantly higher in the OD group. There was no difference in average dyspepsia scores between the 2 dyspeptic groups (21.5 vs 20.4, P > 0.05), but the scores of 'stomach' pain and 'stomach' pain before meals were higher in OD patients than in FD patients (2.65 +/- 1.11 vs 2.16 +/- 0.92, 2.26 +/- 1.26 vs 1.79 +/- 0.92, P < 0.05). In 45.2% of the OD patients and 47.7% of the FD patients, respectively, the severity of symptoms was not related to meals. In subgroups of ulcer-like, dysmotility-like and unspecified dyspepsia, the proportion of patients with symptoms not related to meals was 59.6%, 50.9% and 35.2%, respectively. 2.5% (6/239) of OD patients presented with progressive dysphagia, compared with 2.8% (15/543) of FD patients who presented with intermittent dysphagia. Approximately 8.8% (21/239) of OD patients reported dramatic weight loss accompanied with other severe symptoms, compared with 5.9% (32/543) of FD patients who had no other severe symptoms. A shift in symptom subtypes during the follow-up period was found in 13.8% of FD patients. The infection rate of Helicobacter pylori was higher in the OD group than in the FD group (53.1%vs 42.2%, P < 0.01), but no difference was found among the three subgroups of FD patients (P > 0.05). Halitosis was more often found in dyspeptic patients with H. pylori infection (44.9%vs 17.0% in OD, 47.3%vs 25.4% in FD, P < 0.01). CONCLUSIONS: When dyspepsia patients present with 'stomach' pain or 'stomach' pain before meals, a diagnosis of OD should be considered. Intermittent dysphagia, weight loss not accompanied with other severe symptoms, and halitosis (more often seen in patients with H. pylori infection) might be regarded as the relatively unique symptoms of dyspepsia in some FD patients. In FD, we found that the severity of dyspepsia symptoms was not related to meals in half of the patients, and symptom subtypes might shift over time, this adds difficulty to the management of FD.