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Background Few studies have investigated psychogenic sexual dysfunction including psychogenic erectile dysfunction (pED); the effect of tadalafil on sexual behavior of male rats induced by chronic unpredictable mild stress (CUMS) remains unclear. Aim The aim was to explore the influence of CUMS on sexual behavior of male rats and the effects of tadalafil on that. Methods Adult male rats were divided into 3 groups, including the normal group without CUMS, the model group with 6 weeks’ CUMS, and the tadalafil group with treatment of tadalafil during CUMS. CUMS consists of water deprivation, food deprivation, stroboscopic lightning, white noise, cage tilting, weeding packing, and housing 2 unfamiliar rats. The apomorphine test and vaginal smear test were conducted with the aim to screen out male rats with good erectile function and make preparation for the sexual behavior test, respectively. Outcomes At the end of the study period, the level of anhedonia and sexual function were evaluated by the sucrose preference test, sexual behavior test, and measurement of serum testosterone, dopamine, and 5-HT. Results Sucrose preference showed significant decrease in rats after CUMS. The intromission ratio and total intromission frequency decreased significantly, while the mount latency and ejaculation latency prolonged significantly in CUMS-induced rats when compared with normal rats. Meanwhile, the treatment of tadalafil reversed the level of anhedonia and sexual function in CUMS-induced rats. However, there were no statistical differences in the levels of serum testosterone, dopamine, and 5-HT among groups. Clinical Implications The study constructed an animal model that can provide clinical insights into the mechanism of psychogenic sexual dysfunction and supports the application of tadalafil in pED therapy. Strengths and Limitations We found that CUMS-induced rats exhibited anhedonia and poor sexual function that could be prevented by tadalafil administration. Future research needs to construct the standard of pED model and explore the mechanism of tadalafil on central nervous system. Conclusion Tadalafil could prevent the changes of depression and poor sexual function in rats induced by CUMS, and the method of CUMS and the sexual behavior test should be used in the future for pED modeling.

Introduction: Diabetes mellitus (DM) is one of the major chronic diseases, which enhances the risk of erectile dysfunction (ED). However, the central pathological mechanisms of ED in DM patients are still unclear. Methods: Resting-state functional magnetic resonance imaging (rs-fMRI) data were acquired in 30 type-2 diabetes mellitus (T2DM), 31 T2DM with ED (DM-ED) patients and 30 healthy controls (HCs). The measure of fractional amplitude of low-frequency fluctuation (fALFF) was calculated and compared among groups. Results: Differences of fALFF values were found in the left superior frontal gyrus (medial) and middle temporal gyrus among three groups. Compared with HCs group, T2DM group exhibited lower fALFF values in the left superior frontal gyrus (dorsolateral), anterior cingulate gyrus, calcarine fissure and increased fALFF values in the left postcentral gyrus. Compared with HCs group, DM-ED group exhibited lower fALFF values in the left superior frontal gyrus (medial), middle temporal gyrus, temporal middle (pole) and increased fALFF values in the right postcentral gyrus. Compared with T2DM group, DM-ED group exhibited increased fALFF values in the right median cingulum gyrus and left calcarine fissure. Conclusion: DM-ED patients showed functional changes in brain regions that were closely correlated with sexual dysfunction, which suggested that altered regional brain activity might be related to the pathophysiology of DM-ED.

Chronic prostatitis/chronic pelvic pain syndrome (CP/CPPS) is characterized by chronic pain in pelvic area and lower urinary tract symptoms (LUTS). Previous neuroimaging studies demonstrated that chronic pain was associated with the altered brain activity. However, the pathological mechanisms associated with altered brain control of CP/CPPS are not well-understood. Therefore, we sought to investigate the topological properties of white matter brain networks in patients with CP/CPPS and whether the topological configuration of frontal-parietal control network was disrupted. We collected 19 patients with CP/CPPS and 32 matched healthy controls (HCs). Diffusion tensor imaging data of all participates were used to map the white matter structural networks. Graph theoretical method was applied to investigate the alterations of topological properties of brain network in patients. Moreover, we also investigated whether the alerted brain regions might be correlated with any clinical features of patients by the method of Pearson correlation analysis. Both CP/CPPS patients and HCs exhibited a 'small-world' behavior or economical small-world architecture of the white matter brain networks. In addition, CP/CPPS had a lower global efficiency in the right middle frontal gyrus (orbital part) and a higher global efficiency in the left middle cingulate and paracingulate gyri. CP/CPPS also showed increased local efficiency in the left middle cingulate and paracingulate gyri and paracentral lobule. Moreover, the local efficiency of the left middle cingulate gyrus was positively correlated with the scores of the influence of symptoms on the quality of life. The local efficiency of the left precuneus and right supplementary motor area were positively correlated with the total scores of NIH-CPSI and the scores of pain and discomfort symptoms, respectively. Together, we found that patients with CP/CPPS had alterations of connections within the frontal-parietal control network, which suggested that the altered connectivity involved in the executive control processing procedures might contribute to the pathogenesis of the pelvic pain and LUTS in CP/CPPS. Thus these results provided new insights into the understanding of CP/CPPS.

INTRODUCTION Hyperactivity of the sympathetic nervous system is considered as an important component involved in the pathological mechanisms of premature ejaculation (PE). However, the neural mechanisms of PE with high sympathetic activity are still not well understood. METHODS The activity of the sympathetic innervations in the penis was evaluated by the sympathetic skin response of the penis (PSSR) with an electromyograph and evoked potential equipment. Resting-state functional magnetic resonance imaging (fMRI) data were acquired from 18 PE patients with high sympathetic activity (sPE), 17 PE patients with normal sympathetic activity (nsPE), and 24 healthy controls (HC). We investigated the neural basis of sPE based on the measure of regional homogeneity (ReHo). Moreover, the correlations between brain regions with altered ReHo and PEDT scores and PSSR latencies in the patient group were explored. RESULTS Altered ReHo values among three groups were found in the temporal, cingulated, and parietal cortex in the default mode network (DMN), as well as the temporal cortex in the auditory network (AUD). Compared with HC, Patients with sPE had increased ReHo values of brain regions in DMN, AUD, and decreased ReHo values of brain regions in DMN. In addition, increased ReHo values were found in DMN of patients with nsPE, while decreased ReHo values were found in DMN and the attention network (AN). Moreover, sPE patients had increased ReHo values in AUD and decreased ReHo values in DMN when compared with nsPE patients. Finally, altered ReHo values of brain regions in DMN and AUD were associated with PEDT scores and PSSR latencies in the patient group. CONCLUSION Our results suggested that PE patients had abnormal ReHo values in DMN, AUD, and AN. Patients with sPE were characterized by increased neuronal activity in AUD and decreased activity in DMN. This highlighted the significances of DMN, AUD, and AN in the pathophysiology of PE and also provided potential neuroimaging biomarkers for distinguishing sPE from nsPE and HC.

BACKGROUND Estimated 30%-40% of patients with chronic prostatitis/chronic pelvic pain syndrome (CP/CPPS) suffer from premature ejaculation (PE), which is difficult to cure, but the mechanism is still unknown. Based on the results of our previous clinical studies and animal experiments, we propose that the glutamatergic system dysfunction in the paraventricular nucleus (PVN) may be involved. METHODS To test this hypothesis, we used experimental autoimmune prostatitis (EAP) rats to investigate the effects of CP/CPPS on ejaculation behavior through integrating copulatory behavior testing, neuroelectrophysiologic experiments, and molecular biology technologies. RESULTS Histological examination of prostate tissue in EAP rats exhibited consistent pathological findings with that in CP/CPPS patients. Behavior testing showed that ejaculation latency (EL) of EAP rats significantly shortened compared with the controls (5.1 ± 1.8 vs 9.1 ± 2.4 min, P

INTRODUCTION Recent neuroimaging studies have indicated that some brain areas are involved in the sexual behavior process. Pre-mature ejaculation patients exhibit altered brain activation and abnormal cortical structures. However, there has been no research evaluating the topological organization of structural brain network in anejaculation (AE). METHODS We employed diffusion tensor imaging data and graph theory to examine the whole-brain structural networks among 16 AE patients and 23 healthy controls. In addition, the results of sexual function assessment were also obtained from each patient for symptom assessment. Moreover, the relationships between these clinical features and the altered topological characteristics of AE patients were also explored. RESULTS Decreased clustering coefficient was found in the right amygdala, inferior temporal gyrus, and left pallidum of AE. AE also showed increased path length in the right post-central gyrus, supramarginal gyrus, putamen, pallidum and left heschl gyrus, temporal pole (superior temporal gyrus); however, these altered brain regions showed no significant differences after false discovery rate correction. Moreover, the path length between subcortical and frontal regions was increased in AE. In addition, negative correlations were found between the altered nodal parameters and the amplitudes of somatosensory evoked potentials of dorsal nerve, sympathetic skin response located in the penis. CONCLUSION Together, our results suggest that AE was associated with disruptions in the topological organization of structural brain networks. The decreased clustering coefficient in temporal and subcortical regions and the increased path length between subcortical and frontal regions may contribute to AE. These findings provide new insights into the pathophysiological mechanisms of AE.

Psychological account hypothesizes that premature ejaculation (PE) is a learned pattern of rapid ejaculation maintained by anxiety about sexual failure, whereas neuropsychological accounts hypothesizes that PE is the result of dysfunction of central nervous system regulating ejaculatory. However, the central neural mechanism underlying PE patients with anxiety remains unclear. Resting-state functional magnetic resonance imaging (fMRI) data were collected in 20 PE (diagnoses based on PE Guidelines drafted by the International Society for Sexual Medicine [ISSM]) patients with anxiety and 25 matched healthy controls (HCs) from January 2019 to December 2020. The values of fractional amplitude of low-frequency fluctuation (fALFF) were compared between groups. Moreover, the correlations between fALFF and the severity of PE and anxiety of patients were examined. PE patients with anxiety had increased fALFF values in the right inferior frontal gyrus (opercular part) and middle frontal gyrus. In addition, significant positive correlations were found between the scores of PE diagnostic tool (PEDT) and fALFF values of the right inferior frontal gyrus (opercular part), as well as the right middle frontal gyrus. Moreover, fALFF values of the right inferior frontal gyrus (opercular part) and middle frontal gyrus were positively correlated with the scores of self-rating anxiety scale (SAS). Our results suggested that increased attentional network activity might play a critical role in the neural basis of PE patients with anxiety.

Little is known about how the aberrant structural and functional connectivity relates to the rapid ejaculation. Data of diffusion tensor imaging and resting state functional magnetic resonance imaging were acquired from 32 PE patients and 38 healthy controls (HCs). Firstly, we investigated the structural connectivity (SC) disruptions of PE patients using the method of graph theoretical analysis. Brain regions with impaired nodal strength were then defined as regions of interest (ROI). Secondly, the corresponding functional connectivity (FC) changes were explored. Finally, the correlation analyses were performed between brain areas with abnormal connectivity and clinical characteristics. Structural analysis revealed that PE patients had increased nodal strength in the right superior frontal gyrus (dorsolateral), left middle frontal gyrus, right superior frontal gyrus (medial), right superior frontal gyrus (medial orbital) and decreased nodal strength in the left amygdala. FC analysis revealed that PE patients had decreased FC values in the default mode network, visual recognition network and subcortical network, as well as increased FC values in the attention network. Moreover, correlation analysis revealed that the nodal strength of right superior frontal gyrus (dorsolateral) was negatively associated with the intra-vaginal ejaculation latency, while FC values between the left middle frontal gyrus and middle occipital gyrus were positively related to the total scores of the premature ejaculation diagnostic tool (PEDT). Our results indicated that PE might be associated with the abnormal SC of areas in the prefrontal-amygdala pathway and aberrant FC in certain functional brain networks, especially in default mode network.

Recent research has shown that premature ejaculation (PE) is associated with negative psychological effects (e.g., depression) and the decline of control over ejaculation is accompanied by structural and functional abnormalities in specific brain areas and connections. However, little is known about the alterations of topological organization in the brain network of patients with PE and its relationship with depressive symptom. We acquired diffusion tensor images, sexual function and depression assessment in 16 lifelong PE patients with depressive symptom, 16 lifelong PE patients without depression and 32 age- and education matched healthy controls (HC). The differences in nodal centrality and different hub regions among the three groups were compared. Correlation analyses were conducted between the nodal centrality of brain regions displaying significant group differences and the clinical parameters of PE patients. PE patients with depression had increased nodal degree in the right middle frontal gyrus (orbital part) (ORBmid.R) (survived FDR-correction) compared with HC and PE without depression. PE patients with depression also had increased nodal degree in the left and right posterior cingulate gyrus (PCG.L; PCG.R) compared with HC. In addition, PE with depression had increased nodal betweenness in ORBmid.R compared with HC and PE without depression. Moreover, PE with depression had decreased nodal participation in the right rolandic operculum (ROL.R), postcentral gyrus (PoCG.R) and supramarginal gyrus (SMG.R) compared with HC, and had decreased nodal participation in ROL.R and the right inferior parietal gyrus (IPL.R) compared with PE without depression, while PE without depression had increased nodal participation in the left precuneus (PCUN.L) compared with HC. The degree and betweenness of ORBmid.R were positively correlated with the total scores of Beck depression inventory (BDI) while the participation of IPL.R had a negative association with the total scores of BDI. Different hubs were found among PE patients with and without depression and HC based on nodal degree, betweenness and participation, however, no significant group differences were found in the frequency distribution of high-degree hubs, high-betweenness hubs, provincial hubs and connector hubs. These findings demonstrated that PE was a brain disorder with altered structural connectivity pattern of brain network and depressive symptom, which suggested that altered structural connectivities of the fronto-cingulate-parietal control network were core neurobiological features associated with PE and depression. Together, these alterations could prove helpful for understanding the pathophysiological mechanisms of PE in depression.

Introduction Chronic prostatitis/chronic pelvic pain syndrome (CP/CPPS) is characterized by chronic pain in pelvic area and lower urinary tract symptoms (LUTS). Previous neuroimaging studies demonstrated that chronic pain was associated with altered brain activity. However, the pathological mechanisms associated with altered brain control of CP/CPPS is not well understood. Therefore, we sought to investigate the topological properties of white matter brain networks in patients with CP/CPPS and whether the topological configuration of frontal-parietal control network was disrupted. Methods We collected 19 patients with CP/CPPS and 32 matched healthy controls (HCs). Diffusion tensor imaging data of all participates were used to map the white matter structural networks. Graph theoretical method was applied to investigate the alterations of topological properties of brain network in patients. Moreover, the associations between the alerted brain regions of patients and clinical measurements were analysised by using Pearson correlation analyses. Results Both CP/CPPS patients and HCs exhibited a 'small-world' behaviour or economical small-world architecture of the white matter brain networks. In addition, CP/CPPS had a lower global efficiency in the right middle frontal gyrus (orbital part) and a higher global efficiency in the left middle cingulate and paracingulate gyri. CP/CPPS also showed decreased local efficiency in the left middle cingulate and paracingulate gyri and paracentral lobule. Moreover, the local efficiency of the left middle cingulate gyrus was positively correlated with the scores of the influence of symptoms on the quality of life. The local efficiency of the left precuneus and right supplementary motor area were positively correlated with the total scores of NIH-CPSI and the scores of pain and discomfort symptoms, respectively. Conclusion Together, we found that patients with CP/CPPS had alterations of connections within the frontal-parietal control network, which suggested that the altered connectivity involved in the executive control processing procedures might contribute to the pathogenesis of the pelvic pain and LUTS in CP/CPPS. Thus these results providing new insights into the understanding of CP/CPPS.

Erectile dysfunction (ED) associated with type 2 diabetes is a severe problem that requires effective treatment. Pancreatic kininogenase (PK) has the potential to improve the erectile function of ED patients. This study aims to investigate the effect of PK on erectile function in streptozotocin-induced type 2 diabetic ED rats. To achieve this goal, we divided male Sprague-Dawley rats into five groups. One group was not treated, and the other four groups were treated with saline, sildenafil, PK or sildenafil, and PK, respectively, for 4 weeks after the induction of type 2 diabetic ED. Then, intracavernous pressure under cavernous nerve stimulation was measured, and penile tissue was collected for further study. Endothelial nitric oxide synthase levels, smooth muscle content, endothelium content, cyclic guanosine monophosphate (cGMP) levels in the corpus cavernosum, and neuronal nitric oxide synthase levels in the dorsal penile nerve were measured. Improved erectile function and endothelium and smooth muscle content in the corpus cavernosum were observed in diabetic ED rats. When treating diabetic ED rats with PK and sildenafil at the same time, a better therapeutic effect was achieved. These data demonstrate that intraperitoneal injection of PK can improve erectile function in a rat model of type 2 diabetic ED. With further research on specific mechanisms of erectile function improvement, PK may become a novel treatment for diabetic ED.

Background The role of abnormal communications among large-scale brain networks have been given increasing attentions in the pathophysiology of major depressive disorder (MDD). However, few studies have investigated the effect of antidepressant medication treatment on the information communication of structural brain networks, especially converged from the individual analysis. Methods Nineteen unipolar MDD patients completed two diffusion tensor imaging (DTI) scans before and after 8-week treatment with selective serotonin reuptake inhibitor. DTI data of 37 matched healthy controls were acquired. We focused on a hub-level community structure network, and investigated whether it had differences on the whole structure and which regions drove these differences in terms of modular affiliation and hub role shift. Data were analyzed by the novel permutation network framework, which appraised the topological consistency of hubs and reserved an individual information. Results Compared to the pre-treatment state, post-treatment patients exhibited increasing number of modular members in the modules that included the right medial superior frontal gyrus (SFGmed) or the thalamus. Moreover, the result suggested a hub role shift of the left insula from a provincial-hub before treatment to a connector-hub after treatment. Additionally, reduced inter-module degree in the right SFGmed was positively correlated with the reduced sum score of 17-item Hamilton depression rating scale at the follow-up. Conclusions Antidepressant medication treatment might be associated with modular reconfigurations of hubs within the fronto-limbic circuit. Moreover, increased inter-module connections of the left insula might improve its integration ability, promoting the remission of MDD. The correlation results of the right SFGmed suggested it might be a valuable indicator for treatment response.

Nonorganic erectile dysfunction is a problem with unknown central mechanisms. Changes in brain activity in the amygdala have been observed in human patients. This study aimed to investigate the dopamine system in the basolateral amygdala of male rats with nonorganic erectile dysfunction. We applied chronic mild stress to induce nonorganic erectile dysfunction. After exposure to chronic mild stress, the sucrose consumption test, sexual behaviour test and apomorphine test were used to select depression-like rats with erectile dysfunction as nonorganic erectile dysfunction model rats. The sexual behaviour of these rats after central infusion of a dopamine D1/D2 receptor agonist/antagonist was observed. The expression levels of dopamine D1/D2 receptors and tyrosine hydroxylase in the basolateral amygdala were also measured. The result of the sucrose consumption test, sexual behaviour test and apomorphine test indicated a successful nonorganic erectile dysfunction model. Central infusion of a dopamine D2 receptor agonist increased intromission ratio in model rats. Lower expression levels of tyrosine hydroxylase and the dopamine D2 receptor in the basolateral amygdala were observed in rats with nonorganic erectile dysfunction. These results suggest that impairment of the dopamine D2 receptor pathway in the basolateral amygdala may contribute to the development of nonorganic erectile dysfunction.

Background: Neuroimaging studies have demonstrated that the prefrontal cortex and amygdala play an important role in sexual arousal (SA). However, little is known about the interactions between the prefrontal and cortex amygdala, which mediate the cognitive regulation of emotion and SA. Objective: We seek to determine whether nocturnal erection of psychogenic erectile dysfunction (pED) patients are normal and whether there are changes of topological organization in the prefrontal-amygdala pathway of brain network in pED. In addition, whether there are correlations between network property changes and self-reported emotion and erection. Design, setting, and participants: We used the RigiScan device to evaluate erectile function of patients and employed diffusion MRI and graph theory to construct brain networks of 21 pED patients and 24 healthy controls. Outcome measurements and statistical analysis: We considered four nodal metrics and their asymmetry scores, and nocturnal penile tumescence (NPT) parameters, to evaluate the topological properties of brain networks of pED and their relationships with the impaired self-reported emotion and erection. Results and limitations: All the pED patients showed normal nocturnal penile erection, however impaired self-reported erection and negative emotion. In addition, patients showed lower connectivity degree and strength in the left prefrontal-amygdala pathway. We also found that pED exhibited lower leftward asymmetry in the inferior frontal gyrus. Furthermore, patients showed more hub regions and fewer pivotal connections. Moreover, the degree of the left amygdala of pED showed significantly negative correlation with the self-reported erection and positive correlation with the self-reported negative emotion. Conclusions: Together, these results suggest normal nocturnal erection in pED. However, abnormalities of brain network organization in pED, particularly in the left prefrontal-amygdala pathway, are associated with the impaired self-reported erection and negative emotion.

Background Accumulated evidence has illuminated the topological infrastructure of major depressive disorder (MDD). However, the changes of topological properties of anatomical brain networks in remitted major depressive disorder patients (rMDD) remain an open question. The present study provides an exploratory examination of pattern changes among current major depressive disorder patients (cMDD), rMDD patients and healthy controls (HC) by means of a pattern recognition analysis. Methods Twenty-eight cMDD patients (age range: 22–54, mean age: 39.57), 15 rMDD patients (age range: 23–53, mean age: 38.40) and 30 HC (23–54, mean age: 35.57) were enrolled. For each subject, we computed five kinds of weighted white matter (WM) networks via employing five physiological parameters (i.e. fractional anisotropy, mean diffusivity, λ 1 , λ 2 and λ 3 ) and then calculated three network measures of these weighted networks. We treated these measures as features and fed into a feature selection mechanism to choose the most discriminative features for linear support vector machine (SVM) classifiers. Results Linear SVM could excellently distinguish the three groups with the 100% classification accuracy of recognizing cMDD/rMDD from HC, and 97.67% classification accuracy of recognizing cMDD from rMDD. The further pattern analysis found two types of discriminative patterns among cMDD, rMDD and HC. (i) Compared with HC, both cMDD and rMDD exhibited the similar deficit patterns of node strength primarily involving the salience network (SN), default mode network (DMN) and frontoparietal network (FPN). (ii) Compared with cMDD and rMDD showed the altered pattern of intra-communicability within DMN and inter-communicability between DMN and the other sub-networks including the visual recognition network (VRN) and SN. Limitations The present study had a limited sample size and a lack of larger independent data set to validate the methods and confirm the findings. Conclusions These findings implied that the impairment of MDD was closely associated with the alterations of connections within SN, DMN and FPN, whereas the remission of MDD was benefitted from the network compensatory of intra-communication within DMN and inter-communication between DMN and the other sub-networks (i.e., VRN and SN).

Background Non-organic erectile dysfunction (noED) at functional imaging has been related to abnormal brain activity and requires animal models for further research on the associated molecular mechanisms. Aim To develop a noED animal model based on chronic mild stress and investigate brain activity changes. Methods We used 6 weeks of chronic mild stress to induce depression. The sucrose consumption test was used to assess the hedonic state. The apomorphine test and sexual behavior test were used to select male rats with ED. Rats with depression and ED were considered to have noED. Blood oxygen level-dependent–based resting-state functional magnetic resonance imaging (fMRI) studies were conducted on these rats, and the amplitude of low-frequency fluctuations and functional connectivity were analyzed to determine brain activity changes. Outcomes The sexual behavior test and resting-state fMRI were used for outcome measures. Results The induction of depression was confirmed by the sucrose consumption test. A low intromission ratio and increased mount and intromission latencies were observed in male rats with depression. No erection was observed in male rats with depression during the apomorphine test. Male rats with depression and ED were considered to have noED. The possible central pathologic mechanism shown by fMRI involved the amygdaloid body, dorsal thalamus, hypothalamus, caudate-putamen, cingulate gyrus, insular cortex, visual cortex, sensory cortex, motor cortex, and cerebellum. Similar findings have been found in humans. Clinical Translation The present study provided a novel noED rat model for further research on the central mechanism of noED. Strengths and Limitations The present study developed a novel noED rat model and analyzed brain activity changes based at fMRI. The observed brain activity alterations might not extend to humans. Conclusion The present study developed a novel noED rat model with brain activity alterations related to sexual arousal and erection, which will be helpful for further research involving the central mechanism of noED.

Aim: Despite increasing understanding of the cerebral functional changes and structural abnormalities in erectile dysfunction, alterations in the topological organization of brain networks underlying psychogenic erectile dysfunction remain unclear. Materials and methods: Here, based on the diffusion tensor image data of 25 patients and 26 healthy controls, we investigated the topological organization of brain structural networks and its correlations with the clinical variables using the graph theoretical analysis. Results: Patients displayed a preserved overall small-world organization and exhibited a less connectivity strength in the left inferior frontal gyrus, amygdale and the right inferior temporal gyrus. Moreover, an abnormal hub pattern was observed in patients, which might disturb the information interactions of the remaining brain network. Additionally, the clustering coefficient of the left hippocampus was positively correlated with the duration of patients and the normalized betweenness centrality of the right anterior cingulate gyrus and the left calcarine fissure were negatively correlated with the sum scores of the 17-item Hamilton Depression Rating Scale. Conclusions: These findings suggested that the damaged white matter and the abnormal hub distribution of the left prefrontal and limbic cortex might contribute to the pathogenesis of psychogenic erectile dysfunction and provided new insights into the understanding of the pathophysiological mechanisms of psychogenic erectile dysfunction.

The human brain is a complex network of regions that are structurally interconnected by white matter (WM) tracts. Schizophrenia (SZ) can be conceptualized as a disconnection syndrome characterized by widespread disconnections in WM pathways.To assess whether or not anatomical disconnections are associated with disruption of the topological properties of inter- and intra-hemispheric networks in SZ.We acquired the diffusion tensor imaging data from 24 male patients with paranoid SZ during an acute phase of their illness and from 24 healthy age-matched male controls. The brain FA-weighted (fractional anisotropy-weighted) structural networks were constructed and the inter- and intra-hemispheric integration was assessed by estimating the average characteristic path lengths (CPLs) between and within the left and right hemisphere networks.The mean CPLs for all 18 inter-and intra-hemispheric CPLs assessed were longer in the SZ patient group than in the control group, but only some of these differences were significantly different: the CPLs for the overall inter-hemispheric and the left and right intra-hemispheric networks; the CPLs for the interhemisphere subnetworks of the frontal lobes, temporal lobes, and subcortical structures; and the CPL for the intra- frontal subnetwork in the right hemisphere. Among the 24 patients, the CPL of the inter-frontal subnetwork was positively associated with negative symptom severity, but this was the only significant result among 72 assessed correlations, so it may be a statistical artifact.Our findings suggest that the integrity of intra- and inter-hemispheric WM tracts is disrupted in males with paranoid SZ, supporting the brain network disconnection model (i.e., the (')connectivity hypothesis(')) of schizophrenia. Larger studies with less narrowly defined samples of individuals with schizophrenia are needed to confirm these results.人类大脑是由白质(WM) 束结构性互相连结的 复杂网络。精神分裂症(schizophrenia, SZ) 可以被概念 化为以WM 路径广泛断开为特征的中断综合征。.评估解剖性断开是否与SZ 患者的大脑半球内与 大脑半球间的拓扑性质破坏有关。.我们采集了24 例处于发病急性期的偏执型精 神分裂症男性患者和24 例与之年龄匹配的健康男性对 照组的弥散张量成像(diffusion tensor imaging) 数据。 本研究构建了大脑的部分各向异性加权的(fractional anisotropy-weighted, FA-weighted) 结构网络， 并且通 过估计平均特征路径长度(characteristic path lengths, CPLs) 评估大脑内半球间与半球内的整合。.SZ 患者组的全部18 个所评估的半球间与半球 内的CPL 值均值均长于对照组，但这些差异中只有一 些具有显著性，包括：整体半球间、左半球内部和右 半球内部网络的CPL；额叶、颞叶和皮质下结构的半 球间子网络的CPL；以及右半球内额叶子网络的CPL。 在24 例患者中，双侧额叶子网络间的CPL 与阴性症状 严重程度正相关，但这是72 个相关性分析中唯一显著 的结果，所以它可能只有统计学上的显著意义。.我们的研究结果表明，男性偏执型SZ 患者的脑 半球内和半球间白质束的完整性被破坏，这支持了精 神分裂症的大脑网络中断模型（即“连通性假说”）。 我们需要对更特异的精神分裂症患者样本进行更大规 模的研究来证实这些结果。.本文全文中文版从2015年08月06日起在http://dx.doi.org/10.11919/j.issn.1002-0829.215036可供免费阅览下载.

Previous studies had explored the diagnostic and prognostic value of the structural neuroimaging data of MDD and treated the whole brain voxels, the fractional anisotropy and the structural connectivity as classification features. To our best knowledge, no study examined the potential diagnostic value of the hubs of anatomical brain networks in MDD. The purpose of the current study was to provide an exploratory examination of the potential diagnostic and prognostic values of hubs of white matter brain networks in MDD discrimination and the corresponding impaired hub pattern via a multi-pattern analysis. We constructed white matter brain networks from 29 depressions and 30 healthy controls based on diffusion tensor imaging data, calculated nodal measures and identified hubs. Using these measures as features, two types of feature architectures were established, one only included hubs (HUB) and the other contained both hubs and non hubs. The support vector machine classifiers with Gaussian radial basis kernel were used after the feature selection. Moreover, the relative contribution of the features was estimated by means of the consensus features. Our results presented that the hubs (including the bilateral dorsolateral part of superior frontal gyrus, the left middle frontal gyrus, the bilateral middle temporal gyrus, and the bilateral inferior temporal gyrus) played an important role in distinguishing the depressions from healthy controls with the best accuracy of 83.05%. Moreover, most of the HUB consensus features located in the frontal-parieto circuit. These findings provided evidence that the hubs could be served as valuable potential diagnostic measure for MDD, and the hub-concentrated lesion distribution of MDD was primarily anchored within the frontal-parieto circuit.