Type 2 diabetes is causally associated with depression: a Mendelian randomization analysis / 医学前沿

Type 2 diabetes (T2D) has been associated with a high prevalence of depression.We aimed to determine the causal relation by performing a Mendelian randomization (MR) study using 34 T2D risk genetic variants validated in East Asians as the instrumental variable (IV). An MR analysis was performed involving 11 506 participants from a large longitudinal study. The T2D genetic risk score (GRS) was built using the 34 typical T2D common variants. We used T2D_GRS as the IV estimator and performed inverse-variance weighted (IVW) and Egger MR analysis. The T2D_GRS was found to be associated with depression with an OR of 1.21 (95% CI: 1.07-1.37) after adjustments for age, sex, body mass index, current smoking and drinking, physical activity, education, and marital status. Using T2D_GRS as the IV, we similarly found a causal relationship between genetically determined T2D and depression (OR: 1.84, 95% CI: 1.25-2.70). Though we found no association between the combined effect of the genetic IVs for T2D and depression with EggerMR(OR: 0.95, 95%CI: 0.42-2.14), we found an association for T2D and depression with IVW (OR: 1.75, 95% CI: 1.31-2.46) after excluding pleiotropic SNPs. Overall, the MR analyses provide evidence inferring a potential causal relationship between T2D and depression.

Abnormal Effective Connectivity of the Anterior Forebrain Regions in Disorders of Consciousness / 神经科学通报·英文版

A number of studies have indicated that disorders of consciousness result from multifocal injuries as well as from the impaired functional and anatomical connectivity between various anterior forebrain regions. However, the specific causal mechanism linking these regions remains unclear. In this study, we used spectral dynamic causal modeling to assess how the effective connections (ECs) between various regions differ between individuals. Next, we used connectome-based predictive modeling to evaluate the performance of the ECs in predicting the clinical scores of DOC patients. We found increased ECs from the striatum to the globus pallidus as well as from the globus pallidus to the posterior cingulate cortex, and decreased ECs from the globus pallidus to the thalamus and from the medial prefrontal cortex to the striatum in DOC patients as compared to healthy controls. Prediction of the patients' outcome was effective using the negative ECs as features. In summary, the present study highlights a key role of the thalamo-basal ganglia-cortical loop in DOCs and supports the anterior forebrain mesocircuit hypothesis. Furthermore, EC could be potentially used to assess the consciousness level.

The study of the relapsed patients with major depressive disorder based on spectral dynamic causal modeling / 实用放射学杂志

Objective To explore the effects of abnormal effective connectivity within the default mode network (DMN)in relapsed patients with major depressive disorder.Methods Resting-state functional magnetic resonance imaging (rs-fMRI)data were collected from 21 patients of first-episode depression and 16 patients with relapsed depression,and 37 matched healthy controls.The effective connectivity within the DMN was investigated with spectral dynamic causal modeling (spDCM)method.Results spDCM analysis showed that the effective connections from left parietal cortex(LPC)to right parietal cortex(RPC)and medial frontal cortex(mPFC)were significantly decreased,while the connection from posterior cingulate cortex(PCC)to mPFC was increased in patients of first episode depression compared to healthy controls.Furthermore,the connectivity between mPFC and LPC were enhanced in patients with recurrent depression compared withhealthy control subjects,as well as PCC.Meanwhile,the connectivity between mPFC and PCC was enhanced in patients with relapse depression compared with patients of first episode depression.Conclusion Both first-episode and relapsed patients demonstrated abnormal effective connectivity of LPC,implicating that abnormal LPC connectivity may be associated with the neural substrates of depression.In contrast,the patients with relapsed depression showed aberrant connectivity with the mPFC,suggesting that abnormal effective connectivity of the mPFC may play an important role in the relapse of depression.

Preliminary exploration of the frontal-cingulate functional connection during identifying sad facial expression in depressed patients / 中华行为医学与脑科学杂志

Objective To analyze the difference of frontal-cingulate functional connection between patients with major depression and healthy controls in recognization of sad facial expression, and discuss the neutral basis of emotional bias in preliminary. Methods 12 female patients with major depression and 12 matched healthy controls were scanned. The intensities of brain activation in the process of sad and neutral facial expression recognition were analyzed, and the strengths of frontal-cingulate functional connection were compared between the two groups based on dynamic causal modeling. Results Comparing the stimulus adjusting connection models with Bayesian model indicated that model Ⅱ matched with the observation data better. In the comparison between model Ⅱ and model I ,the average Bayes factor was more than 7.38. In the comparison between model Ⅱ and model Ⅲ,the average Bayes factor was more than 2.71. Calculating the intrinsic connection parameters and stimulus adjusting connection parameters based on intrinsic connection model and stimulus adjusting connection model( model Ⅱ ), the result showed that connection strength between anterior cingulate and right inferior frontal gyrus in depression was greater than that in healthy controls. Conclusion The frontal-cingulate functional connection of patients with major depression is increased abnormally ,which may be the neural basis of negative emotional bias.

Factors Influencing Family Functioning in Families with Breast Cancer in the Mother / 성인간호학회지

The purpose of this study was : 1) to develop and test a theoretical model examining relationships among social support( and social network size ), illness demands, marital adjustment, family coping, and an outcome measure of family functioning in response to a mother's breast cancer in the early postdiagnostic phase ; 2) to investigate the sources of functional social support : and 3) to assess characteristics of social support networks for Korean families with breast cancer. This study used a cross-sectional, correlational design with a causal modeling methodology to test the specified relationships in the recursive theoretical model. the convenience sample of this study consisted of 82 married Korean couples with recently diagnosed breast cancer in the child-rearing mother. Six standardized questionnaires were used to measure the theoretical concepts : social support (ISSB), social network(ASSIS), illness demands(DOII), marital adjustment(DAS), family coping(F-COPES), and family functioning(FACESII). The theoretical model was tested on the aggregated couples' data( family data ) and on mothers and fathers data. Path analysis results from the mothers and the fathers revealed different patterns. A core set of predictive variables were identified with three data sets showing consistent effects on family functioning level-marital adjustment and family coping, marital adjustment and family functioning, and family coping and family functioning. Namely, the level of family functioning was directly and positively affected by family coping behavior and the level of marital adjustment ; the level of marital adjustment had a direct positive effect on family coping behavior. In two reduced models from couples' and mothers' data, three sets of predicted relationships were supported, social support and marital adjustment, and s and marital adjustment. The level of social support received had a direct positive effect on both the level of marital adjustment and family coping behavior, and the experienced illness demands had a direct negative effect on the level of marital adjustment. Few significant gender differences were found in terms of 1) actual and perceived network sizes, need for support, and satisfaction with the support received for each type of functional social support, 20 total network size encompassing all types of functional social support, as well as, 3) the amount of functional social support received. These findings may prove useful for health care professionals working with Korean families with breast cancer or other chronic illness.