Circular RNA SNX27 Facilitates Gastric Cancer Progression By Sponging miR-638.

BACKGROUND/AIMS:  Accumulating evidences have shown an important role of circular RNAs (circRNAs) in the tumorigenesis of gastric cancer (GC). Nevertheless, whether circSNX27 plays a role in GC remains undetermined. MATERIALS AND METHODS:  Relative expression of circRNAs and related microRNAs (miRNAs) in GC tissues and cells were tested by quantitative reverse transcription polymerase chain reaction. Specific short hairpin RNAs were designed to knockdown the expression of circSNX27 in GC cells. CCK-8, colony formation, flow cytometry, wound healing, and transwell assays were used to access the function of circSNX27 silencing on GC cells. The target miRNAs of circSNX27 were predicted by 2 databases, circBank and Circinteractome. Dualluciferase reporter assay was used to verify the interaction between circSNX27 and miR-638. RESULTS:  circSNX27 was found to be upregulated in GC tissues and cell lines compared with normal controls. Silencing of circSNX27 repressed GC cell viability, proliferation, migration, and invasion. Moreover, circSNX27 silencing could accelerate GC cell apoptosis. Additionally, we found that circSXN27 decreased the expression of miR-638 by directly binding to it in GC cells. CONCLUSION:  Our results indicated that circSXN27 facilitated GC progression by acting as a sponge of miR-638.

Efficacy of Endoscopic Tissue Adhesive in Patients with Gastrointestinal Tumor Bleeding.

BACKGROUND: Gastrointestinal tumors bleeding remains a significantly clinical challenge due to its resistance to conventional endoscopic hemostasis methods. While the efficacy of endoscopic tissue adhesives (ETA) in variceal bleeding has been established, its role in gastrointestinal tumor bleeding (GITB) remains ambiguous. AIMS: This study aims to assess the feasibility and effectiveness of ETA in the treatment of GITB. METHODS: The study enrolled 30 patients with GITB who underwent hemostasis through Histoacryl® tissue glue injection. Hemostasis success rates, ETA-related adverse events, and re-bleeding rates were evaluated. RESULTS: ETA application achieved successful hemostasis at all tumor bleeding sites, with immediate hemostasis observed in all 30 (100.0%) patients. Among the initially hemostasis cases, 5 patients (17.0%) experienced re-bleeding within 30 days, and the 60 day re-bleeding rate was 20.0% (6/30). Expect for one case of vascular embolism, no adverse events related with ETA application were reported. The 6 month survival was 93%. CONCLUSION: ETA demonstrated excellent immediate hemostasis success rate in GITB cases and showed promising outcomes in prevention re-bleeding.

Circ-EIF3I Promotes Hepatocellular Carcinoma Progression Through Modulating miR-361-3p/DUSP2 Axis.

Hepatocellular carcinoma (HCC) is one of the most common malignant cancers globally. Circular RNAs (circRNAs) have been implicated in the development of HCC. Previous studies have confirmed that circ-EIF3I plays an important role in the progress of lung cancer. Nevertheless, the biological functions of circ-EIF3I and the underlying mechanisms by which they regulate HCC progression remain unclear. In this study, the regulatory mechanism and targets were studied with bioinformatics analysis, luciferase reporting analysis, transwell migration, Cell Counting Kit-8, and 5-Ethynyl-2'-deoxyuridine analysis. In addition, in vivo tumorigenesis and metastasis assays were employed to evaluate the roles of circ-EIF3I in HCC. The result shows that the circ-EIF3I expression was increased in HCC cell line, which means that circ-EIF3I plays a role in the progression of HCC. Downregulation of circ-EIF3I suppressed HCC cells' proliferation and migration in both in vivo and in vitro experiments. Bioinformatics and luciferase report analysis confirmed that both miR-361-3p and Dual-specificity phosphatase 2 (DUSP2) were the downstream target of circ-EIF3I. The overexpression of DUSP2 or inhibition of miR-361-3p restored HCC cells' proliferation and migration ability after silence circ-EIF3I. Taken together, our study found that downregulation of circ-EIF3I suppressed the progression of HCC through miR-361-3p/DUSP2 Axis.

Effect of perioperative high-dose transdermal nicotine patch on pain sensitivity among male abstinent tobacco smokers undergoing abdominal surgery: A randomized controlled pilot study.

BACKGROUND AND AIMS: Previous studies have focused on the role of perioperative nicotine replacement therapy (NRT) in improving the success rate of long-term smoking cessation in tobacco smokers. This study aimed to measure the effectiveness of high-dose NRT in alleviating postoperative pain for male abstinent smokers receiving abdominal surgery. DESIGN: This was a parallel-group, randomized, double-blind and controlled pilot trial. SETTING AND PARTICIPANTS: In total, 101 male smoking-abstinent patients from the Eastern Hepatobiliary Surgery Hospital, Shanghai, China, from 8 October 2018 to 10 December 2021. INTERVENTIONS: Patients started smoking cessation on admission to the hospital ward. Patients received 24-hour transdermal nicotine patches (n = 50) or placebo (n = 51) every day from admission until 48 hours after surgery. MEASUREMENTS: The primary outcomes were pre-surgery pain thresholds and total consumption of analgesics within the first 48 hours after surgery. Secondary outcomes included postoperative pain and sedation scores, nausea, vomiting and fever frequency within the treatment period. FINDINGS: Both pre-surgery electrical and mechanical pain thresholds in the NRT group were higher than those in the placebo group (P = 0.004 and P = 0.020, respectively). The 48-hour postoperative analgesic consumption was significantly lower for smoking-abstinent patients receiving NRT than those receiving placebo (standardized morphine equivalent requirement, median [interquartile range], 1.80 [1.47, 2.32] mg/kg vs 2.22 [1.62, 2.82] mg/kg, P = 0.011). Postoperative pain intensity was significantly lower in the NRT group than that in the placebo group at 1st hour and 24th hour post-surgery (P < 0.001 and P = 0.012, respectively). The incidence of treatment-related adverse events was not significantly different between groups. CONCLUSIONS: Perioperative high-dose nicotine replacement therapy may help to relieve postoperative pain among male smoking-abstinent patients undergoing abdominal surgery.

The Effect of Tramadol Versus Sufentanil on Controlling Postoperative Pain for Men Who Smoke and Do Not Smoke: A Randomized Clinical Trial.

BACKGROUND: Smoking behavior alters the analgesic threshold, which challenges postoperative pain management for patients who smoke. OBJECTIVES: We aimed to assess the analgesic efficacy of tramadol versus sufentanil in relieving postoperative pain for patients who do and do not smoke who underwent a partial hepatectomy. STUDY DESIGN: Double-blinded randomized controlled trial. SETTING: Eastern Hepatobiliary Surgery Hospital, Shanghai, China. METHODS: All patients in this study were men. A total of 66 patients who smoke were randomly assigned to receive tramadol or sufentanil (n = 33 each). In addition, a total of 66 patients who do not smoke were randomly assigned to receive tramadol or sufentanil (n = 33 each). The primary outcome was the consumption of additional analgesics within the first 48 hours to control postoperative pain. Secondary outcomes included the postoperative pain level, the frequency of postoperative nausea and vomiting, the sedation score, and the frequency of fever within 48 hours postsurgery. RESULTS: A significant interaction between "analgesic strategy" and "smoking history" was detected on the consumption of additional analgesics. In those who smoke, the requests for additional doses of analgesics were significantly less in those receiving tramadol than those receiving sufentanil; such a difference was not observed in those who do not smoke. The postoperative pain level was not significantly different between the tramadol group and the sufentanil group within patients who smoke within 48 hours postsurgery. The incidence of treatment-related adverse events was not significantly different between the tramadol group and the sufentanil group within both those who do and do not smoke. LIMITATIONS: Only men patients were included. Also, the superior analgesic effect and the incidence of adverse events of tramadol in patients who smoke were only assessed within the first 48 hours postsurgery. CONCLUSIONS: Our data suggest that tramadol has a better analgesic effect than sufentanil in relieving postoperative pain in patients who smoke.

[Central neural mechanism of increased pain sensitivity induced by nicotine abstinence].

Nicotine is the main addictive component in cigarettes that motivates dependence on tobacco use for smokers and makes it difficult to quit through regulating a variety of neurotransmitter release and receptor activations in the brain. Even though nicotine has an analgesic effect, clinical studies demonstrated that nicotine abstinence reduces pain threshold and increases pain sensitivity in smoking individuals. The demand for opioid analgesics in nicotine abstinent patients undergoing surgery has greatly increased, which results in many side effects, such as nausea, vomiting, and respiratory depression, etc. In addition, these side effects would hinder patients' physical and psychological recovery. Therefore, identifying the neural mechanism of the increase of pain sensitivity induced by nicotine abstinence and deriving a way to cope with the increased demand for postoperative analgesics would have enormous basic and clinical implications. In this review, we first discussed different experimental pain stimuli (e.g., cold, heat, and mechanical pain)-induced pain sensitivity changes after a period of nicotine dependence/abstinence from both animal and human studies. Then, we summarized the effects of the brain neurotransmitter release (e.g., serotonin, norepinephrine, endogenous opioids, dopamine, and γ-aminobutyric acid) and their corresponding receptor activation changes after nicotine abstinence on pain sensitivity. Finally, we discussed the limits in recent studies. We proposed that more attention should be paid to human studies, especially studies among chronic pain patients, and functional magnetic resonance imaging might be a useful tool to reveal the mechanisms of abstinence-induced pain sensitivity changes. Besides, considering the influence of duration of nicotine dependence/abstinence and gender on pain sensitivity, we proposed that the effects of nicotine abstinence and individual differences (e.g., duration of abstinence from smoking, chronic/acute abstinence, and gender) on abstinence-induced pain sensitivity should be fully considered in formulating pain treatment protocols. In summary, this paper could deepen our understanding of nicotine abstinence-induced pain sensitivity changes and its underlying neural mechanism, and could also provide effective scientific theories to guide clinical pain diagnosis and treatment, which has important clinical significance.

Cyclin-dependent kinase like 3 promotes triple-negative breast cancer progression via inhibiting the p53 signaling pathway.

It has been reported that cyclin-dependent kinase like 3 (CDKL3) plays a crucial role in cell proliferation and migration in several cancers. However, the function of CDKL3 in triple-negative breast cancer (TNBC) is still unclear. In the present study, immunohistochemistry (IHC) was conducted to detect the CDKL3 expression. CCK-8, flow cytometry, Transwell assays, and mice xenograft models, were performed to explore the roles of CDKL3 on the proliferation and migration of TNBC in vitro and in vivo. Besides, protein chip analysis was used to screen the potential pathways, which was further confirmed by promoter activity assay, western blotting, and CCK-8 assay. Our findings reveal a high expression of CDKL3 in TNBC tissues, which is closely related to a poor prognosis of patients with TNBC. In TNBC cells, CDKL3 knockdown inhibits cell proliferation and migration, whereas CDKL3 overexpression has exactly the opposite effect. Consistently, CDKL3 knockdown induces cell apoptosis in vitro but suppresses tumor growth in vivo. Furthermore, CDKL3 knockdown increases p53 expression and reduces cell viability, and these effects are significantly weakened by the p53 inhibitor, PFT-α. In conclusion, the current study highlights that CDKL3 promotes TNBC progressions via regulating the p53 signaling pathway, suggesting that CDKL3 is a novel therapeutic target for TNBC treatment.

Serum IL-5 and IFN-γ Are Novel Predictive Biomarkers for Anti-PD-1 Treatment in NSCLC and GC Patients.

BACKGROUND: Because responses of patients with cancer to immunotherapy can vary in success, effective biomarkers are urgently needed for predicting clinical response with anti-PD-1 treatment. We aimed to evaluate the IL-5 and IFN-γ level with the response of anti-PD-1 blockade in non-small-cell lung cancer (NSCLC) and gastric cancer (GC). METHODS: Metastatic NSCLC and GC patients treated with anti-PD-1 monoclonal antibody were studied. Blood samples were taken before PD-1 McAb treatment, after the first cycle treatment, and during efficacy evaluation. The association between IL-5 and IFN-γ levels and clinical response were analyzed by the nonparametric Wilcoxon matched-pairs ranked tests. The progression-free survival (PFS) time was obtained by imaging evaluation and telephone follow-up of all the patients. Kaplan-Meier and the log rank test were used to plot the survival curve. RESULTS: IL-5 and IFN-γ levels were detected in the peripheral blood of 40 NSCLC and 35 GC patients who have received anti-PD-1 treatment. In effective group, IL-5 and IFN-γ levels at best response points significantly decreased (P < 0.001) compared with pretherapeutic levels in NSCLC and GC patients with lymph node or distant metastasis. Compared with pretherapeutic levels, IL-5 and IFN-γ levels largely increased as the tumor progresses (P < 0.01). Higher IL-5 and IFN-γ levels before treatment indicated shorter progression-free survival in patients with NSCLC metastasis (P = 0.007, P = 0.0111). Moreover, their levels also accurately reflected the pseudoprogression of two NSCLC patients to anti-PD-1 treatment. CONCLUSIONS: Our results suggested that serum IL-5 and IFN-γ levels could be an effective indicator for predicting clinical efficacy and survival with anti-PD-1 blockade in NSCLC and GC patients.

Cholinesterase is Associated With Prognosis and Response to Chemotherapy in Advanced Gastric Cancer.

Background: Cholinesterase (CHE) is a routine serum biomarker in gastric cancer (GC). However, little research has been done on its clinical value in advanced GC. In addition, it is not clear whether it can be used as biomarker for the response and prognosis of advanced GC patients. Methods: Between Jan. 2013 and Dec. 2016, a total of 150 patients with advanced GC treated with first-line chemotherapy were admitted to Changzhou Tumor Hospital Affiliated to Soochow University. We retrospectively identified serum CHE level on the day before chemotherapy and at the end of chemotherapy and abstracted clinicopathologic features and treatment outcomes. Univariate and multivariate survival analyses were performed to assess the relationship between serum CHE levels and progression-free survival (PFS) and overall survival (OS). Results: A total of 150 advanced GC patients were included and divided into serum level ≥5,000 IU/L and serum level <5,000 IU/L. CHE level lower than 5,000 IU/L was associated with poorer PFS (HR, 1.60; 95% CI, 1.141-2.243; p = 0.006), poorer OS (HR, 1.76; 95% CI, 1.228-2.515; p = 0.002) and trend of poorer response (HR, 0.56; 95% CI, 0.272-1.129; p = 0.104). In univariate and multivariate logistic regression analysis, only liver metastasis and PS score were significantly associated with objective response (p < 0.05). The medium PFS was 8.0 months in patients with post-treatment CHE increased vs. 3.8 months in patients with CHE decreased after chemotherapy (HR, 1.82; 95% CI 1.28-2.57; p = 0.0002). The medium OS was 13.1 months in patients with increased post-treatment CHE vs. 8.1 months in patients with decreased post-treatment CHE (HR, 1.87; 95% CI 1.29-2.71; p = 0.0002). Conclusion: Advanced GC with CHE levels below 5,000 IU/L was significantly associated with poor PFS and OS. The results suggested that CHE analysis before chemotherapy was a promising prognostic marker for advanced GC.

The changes of brain functional networks in young adult smokers based on independent component analysis.

Intrinsic functional connectivity (FC) networks, including the default mode network (DMN), central executive network (CEN), and salience network (SN), have been implicated in nicotine addiction. However, litter evidence exists about the abnormalities in the three networks in young adult smokers. Forty-eight young adult smokers and 49 age- and gender-matched non-smokers were recruited in the present study. Resting-state functional magnetic resonance imaging (fMRI) data were analyzed by a combination of independent component analysis (ICA) and dual regression to identify potential differences of FC patterns in the DMN, CEN, and SN. Compared to non-smokers, young adult smokers showed enhanced FC of the left posterior cingulate cortex (LPCC), right medial prefrontal cortex (RMPFC) and right precuneus within the DMN network, of the right dorsolateral prefrontal cortex (DLPFC) within the right CEN, and of the left anterior insula (LAI) within the SN. We also found increased FC between the DMN, CEN and key node of the SN (anterior insula, AI). Correlation analysis showed that the increased FC within the networks was significantly correlated with smoking behaviors (pack-years, smoking duration, FTND, first smoking age, and number of cigarettes per day). Our findings may provide additional evidence for conceptualizing the framework of nicotine addiction as a disease of intercommunicating brain networks.

A retrospective analysis of plasma concentration monitoring of fluorouracil in patients with advanced colorectal cancer.

Objectives: To analyse the results of fluorouracil (5-FU) plasma concentration monitoring in patients with advanced colorectal cancer after 5-FU treatment, and to provide a reference for the application prospect of 5-FU plasma concentration monitoring technology. Methods: A retrospective analysis was performed with advanced colorectal cancer patients treated with 5-FU from March 2015 to August 2018. The results of plasma concentration monitoring of 5-FU, severe adverse reactions, and anti-tumour efficacy were analysed. Results: Among 47 patients, 5-FU plasma concentration monitoring was carried out a total of 289 times. The area under the receiver operating characteristic (ROC) curve (AUC) reflecting 5-FU exposure in vivo was 2.8-158 mg*h/L (41±94.6 mg*h/L). Mean AUC range within the target range (20-30 mg*h/L) for each patient was observed in 28.8% of patients. The overall incidence of related severe adverse reactions in the AUC ≤30 mg*h/L group was lower than that in the >30 mg*h/L group (24.0% and 50.0%, respectively) (p=0.06), and the incidence of severe neutropenia was 12.0% and 40.9%, respectively (p=0.05). The disease control rate and overall response rate of the AUC <20 mg*h/L group was lower than that of the ≥20 mg*h/L group: 83.3% vs 97.1% (p=0.19) and 25.0% vs 51.4% (p = 0.10), respectively. Conclusions: The 5-FU plasma concentration monitoring technique can improve the safety and efficacy of 5-FU administration to advanced colorectal cancer patients. It is expected to become an important means to individualise 5-FU use in the Chinese population.

Transcutaneous Electrical Nerve Stimulation in Relieving Neuropathic Pain: Basic Mechanisms and Clinical Applications.

PURPOSE OF REVIEW: Transcutaneous electrical nerve stimulation (TENS) is widely used as a non-pharmacological approach for pain relief in a variety of clinical conditions. This manuscript aimed to review the basic mechanisms and clinical applications regarding the use of TENS for alleviating the peripheral (PNP) and central neuropathic pain (CNP). RECENT FINDINGS: Basic studies on animal models showed that TENS could alleviate pain by modulating neurotransmitters and receptors in the stimulation site and its upper levels, including the spinal cord, brainstem, and brain. Besides, many clinical studies have investigated the efficacy of TENS in patients with CNP (caused by spinal cord injury, stroke, or multiple sclerosis) and PNP (induced by diabetes, cancer, or herpes zoster). Most clinical trials have demonstrated the efficacy of TENS in attenuating neuropathic pain and suggested that appropriate stimulation parameters (e.g., stimulation frequency and intensity) were critical to improving the analgesic effects of TENS. However, there are some conflicting findings related to the efficacy of TENS in relieving neuropathic pain. With optimized stimulation parameters, TENS would be effective in attenuating neuropathic pain. To obtain sufficient evidence to support the use of TENS in the clinic, researchers recommended performing multicenter clinical trials with optimized TENS protocols for the treatment of various CNP and PNP.

12-h abstinence-induced functional connectivity density changes and craving in young smokers: a resting-state study.

Studying the neural correlates of craving to smoke is of great importance to improve treatment outcomes in smoking addiction. According to previous studies, the critical roles of striatum and frontal brain regions had been revealed in addiction. However, few studies focused on the hub of brain regions in the 12 h abstinence induced craving in young smokers. Thirty-one young male smokers were enrolled in the present study. A within-subject experiment design was carried out to compare functional connectivity density between 12-h smoking abstinence and smoking satiety conditions during resting state in young adult smokers by using functional connectivity density mapping (FCDM). Then, the functional connectivity density changes during smoking abstinence versus satiety were further used to examine correlations with abstinence-induced changes in subjective craving. We found young adult smokers in abstinence state (vs satiety) had higher local functional connectivity density (lFCD) and global functional connectivity density (gFCD) in brain regions including striatal subregions (i.e., bilateral caudate and putamen), frontal regions (i.e., anterior cingulate cortex (ACC) and orbital frontal cortex (OFC)) and bilateral insula. We also found higher lFCD during smoking abstinence (vs satiety) in bilateral thalamus. Additionally, the lFCD changes of the left ACC, bilateral caudate and right OFC were positively correlated with the changes in craving induced by abstinence (i.e., abstinence minus satiety) in young adult smokers. The present findings improve the understanding of the effects of acute smoking abstinence on the hubs of brain gray matter in the abstinence-induces craving and may contribute new insights into the neural mechanism of abstinence-induced craving in young smokers in smoking addiction.

Altered interhemispheric resting-state functional connectivity in young male smokers.

With the help of advanced neuroimaging approaches, previous studies revealed structural and functional brain changes in smokers compared with healthy non-smokers. Homotopic resting-state functional connectivity between the corresponding regions in cerebral hemispheres may help us to deduce the changes of functional coordination in the whole brain of young male smokers. Functional homotopy reflects an essential aspect of brain function and communication between the left and right cerebral hemispheres, which is important for the integrity of brain function. However, few studies used voxel mirrored homotopic connectivity (VMHC) method to investigate the changes of homotopic connectivity in young male smokers. Twenty-seven young male smokers and 27 matched healthy male non-smokers were recruited in our study. Compared with healthy male non-smokers, young male smokers showed decreased VMHC values in the insula and putamen, and increased VMHC values in the prefrontal cortex. Correlation analysis demonstrated that there were significant positive correlations between the average VMHC values of the prefrontal cortex and pack-years in young male smokers. In addition, significant negative correlation was found between the average VMHC values in the insula and pack-years. Our results revealed the disrupted homotopic resting-state functional connectivity in young male smokers. The novel findings may extend our understanding of smoking.

Abnormal brain white matter network in young smokers: a graph theory analysis study.

Previous diffusion tensor imaging (DTI) studies had investigated the white matter (WM) integrity abnormalities in some specific fiber bundles in smokers. However, little is known about the changes in topological organization of WM structural network in young smokers. In current study, we acquired DTI datasets from 58 male young smokers and 51 matched nonsmokers and constructed the WM networks by the deterministic fiber tracking approach. Graph theoretical analysis was used to compare the topological parameters of WM network (global and nodal) and the inter-regional fractional anisotropy (FA) weighted WM connections between groups. The results demonstrated that both young smokers and nonsmokers had small-world topology in WM network. Further analysis revealed that the young smokers exhibited the abnormal topological organization, i.e., increased network strength, global efficiency, and decreased shortest path length. In addition, the increased nodal efficiency predominately was located in frontal cortex, striatum and anterior cingulate gyrus (ACG) in smokers. Moreover, based on network-based statistic (NBS) approach, the significant increased FA-weighted WM connections were mainly found in the PFC, ACG and supplementary motor area (SMA) regions. Meanwhile, the network parameters were correlated with the nicotine dependence severity (FTND) scores, and the nodal efficiency of orbitofrontal cortex was positive correlation with the cigarette per day (CPD) in young smokers. We revealed the abnormal topological organization of WM network in young smokers, which may improve our understanding of the neural mechanism of young smokers form WM topological organization level.

Reduced Thalamus Volume May Reflect Nicotine Severity in Young Male Smokers.

Introduction: Nicotine acts as an agonist at presynaptic nicotinic acetylcholine receptors and to facilitate synaptic release of several neurotransmitters including dopamine and glutamate. The thalamus has the highest density of nicotinic acetylcholine receptors in the brain, which may make this area more vulnerable to the addictive effects of nicotine. However, the volume of thalamus abnormalities and the association with smoking behaviors in young smokers remains unknown. Methods: Thirty-six young male smokers and 36 age-, gender- and education-matched nonsmokers participated in the current study. The nicotine dependence severity and cumulative effect were assessed with the Fagerström test for nicotine dependence (FTND) and pack-years. We used subcortical volume analyses method in FreeSurfer to investigate the thalamus volume differences between young smokers and nonsmokers. Correlation analysis was used to investigate the relationship between thalamus volume and smoking behaviors (pack-years and FTND) in young smokers. Results and Conclusions: Relative to nonsmokers, the young smokers showed reduced volume of bilateral thalamus. In addition, the left thalamus volume was correlated with FTND in young smokers. It is hoped that our findings can shed new insights into the neurobiology of young smokers. Implications: In this article, we investigated the changes of thalamus volume in young male smokers compared with nonsmokers. Reduced left thalamus volume was correlated with FTND in young smokers, which may reflect nicotine severity in young male smokers.

Decreased Global Network Efficiency in Young Male Smoker: An EEG Study during the Resting State.

Previous electroencephalogram (EEG) studies revealed reduced spectral power during the resting state in smokers. However, few studies investigated the changes of global brain networks during the resting state in young smokers by EEG. In the present study, we used minimum spanning tree (MST) to assess the differences of global network efficiency between young smoker (n = 20) and nonsmokers (n = 20). Compared with healthy nonsmokers, young smokers showed decreased leaf fraction, kappa value, increased diameter and eccentricity value in alpha band (r = 0.574, p = 0.008), which suggested the global network efficiency was decreased in young smokers. We also found positive correlation between leaf fraction and onset time of smoking in smokers. These results provided more scientific evidence of the abnormal neural oscillations of young smokers and improved our understanding of smoking addiction.

White matter integrity of central executive network correlates with enhanced brain reactivity to smoking cues.

The attentional bias to smoking cues contributes to smoking cue reactivity and cognitive declines underlines smoking behaviors, which were probably associated with the central executive network (CEN). However, little is known about the implication of the structural connectivity of the CEN in smoking cue reactivity and cognitive control impairments in smokers. In the present study, the white matter structural connectivity of the CEN was quantified in 35 smokers and 26 non-smokers using the diffusion tensor imaging and deterministic fiber tractography methods. Smoking cue reactivity was evaluated using cue exposure tasks, and cognitive control performance was assessed by the Stroop task. Relative to non-smokers, smokers showed increased fractional anisotropy (FA) values of the bilateral CEN fiber tracts. The FA values of left CEN positively correlated with the smoking cue-induced activation of the dorsolateral prefrontal cortex and right middle occipital cortex in smokers. Meanwhile, the FA values of left CEN positively correlated with the incongruent errors during Stroop task in smokers. Collectively, the present study highlighted the role of the structural connectivity of the CEN in smoking cue reactivity and cognitive control performance, which may underpin the attentional bias to smoking cues and cognitive deficits in smokers. The multimodal imaging method by forging links from brain structure to brain function extended the notion that structural connections can modulate the brain activity in specific projection target regions. Hum Brain Mapp 38:6239-6249, 2017. © 2017 Wiley Periodicals, Inc.

The left dorsolateral prefrontal cortex and caudate pathway: New evidence for cue-induced craving of smokers.

Although the activation of the prefrontal cortex (PFC) and the striatum had been found in smoking cue induced craving task, whether and how the functional interactions and white matter integrity between these brain regions contribute to craving processing during smoking cue exposure remains unknown. Twenty-five young male smokers and 26 age- and gender-matched nonsmokers participated in the smoking cue-reactivity task. Craving related brain activation was extracted and psychophysiological interactions (PPI) analysis was used to specify the PFC-efferent pathways contributed to smoking cue-induced craving. Diffusion tensor imaging (DTI) and probabilistic tractography was used to explore whether the fiber connectivity strength facilitated functional coupling of the circuit with the smoking cue-induced craving. The PPI analysis revealed the negative functional coupling of the left dorsolateral prefrontal cortex (DLPFC) and the caudate during smoking cue induced craving task, which positively correlated with the craving score. Neither significant activation nor functional connectivity in smoking cue exposure task was detected in nonsmokers. DTI analyses revealed that fiber tract integrity negatively correlated with functional coupling in the DLPFC-caudate pathway and activation of the caudate induced by smoking cue in smokers. Moreover, the relationship between the fiber connectivity integrity of the left DLPFC-caudate and smoking cue induced caudate activation can be fully mediated by functional coupling strength of this circuit in smokers. The present study highlighted the left DLPFC-caudate pathway in smoking cue-induced craving in smokers, which may reflect top-down prefrontal modulation of striatal reward processing in smoking cue induced craving processing. Hum Brain Mapp 38:4644-4656, 2017. © 2017 Wiley Periodicals, Inc.

12h abstinence-induced right anterior insula network pattern changes in young smokers.

BACKGROUND: The strong craving to smoke is a core factor of smoking abstinence that precipitates relapse. Insula plays critical roles in maintaining nicotine dependence, especially in the interoceptive awareness of craving. Despite evidence indicating a link between insula and abstinence-induced craving, less is known about the neural basis of abstinence-induced craving from the circuit level of insula. METHODS: The present study examined the effects of 12h of abstinence from smoking on the resting state functional connectivity (RSFC) of anterior (AI) and posterior insula in young smokers using a within-subject design. Thirty-three young male smokers underwent functional magnetic resonance imaging scanning on two separate sessions: (1) smoking satiety and (2) abstinence (after ≥12h of smoking deprivation), in counterbalanced order. Multiple regression analysis was applied to investigate the possible relationships between the RSFC changes of insula (abstinence minus satiety) and the abstinence-induced craving changes. RESULTS: Smoking abstinence state (versus satiety) was associated with increased RSFC between right AI and right medial orbitofrontal cortex (OFC), ventromedial prefrontal cortex as well as anterior cingulate cortex. The abstinence-induced RSFC changes between right AI and right lateral OFC was significantly correlated with the craving changes. CONCLUSIONS: These findings improve the understanding of the effects of short-term smoking abstinence on insula circuit connectivity and may contribute new insights into the neural basis of abstinence-induced craving to smoke.