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Objective:To investigate the difference of brain activity intensity between abstinent methamphetamine-dependent (AMD) patients and healthy controls using amplitude of low-frequency fluctuation (ALFF).Methods:From April 2016 to March 2017, 29 male AMD patients from Pingtang compulsory rehabilitation center in Changsha City, Hunan Province and 31 healthy male controls were prospectively recruited. The general conditions of all AMD patients, including age of first use of MA, months of MA use, monthly MA consumption, MA use frequency of the last year and the last month, current months of drug withdrawal, times of drug withdrawal, self-assessment score of drug craving when taking drugs, smoking history (whether smoking and smoking years), drinking history (whether drinking and drinking years). The rest functional MRI data were collected. DPABI software package was used to preprocess the data and calculate ALFF value of each voxel in the whole brain of the subjects of two groups. Two samples t-test and alphasim multiple comparison correction were used. Nuclei with voxel level P<0.01 and voxel number>71 were considered as regions with significant differences between two groups, corresponding to corrected P<0.05. ALFF mean value was extracted for each region with significant differences. Taking smoking and drinking as covariates, the correlations between the mean ALFF values of regions with significant differences and MA use and abstinence were analyzed. Results:Compared with the healthy control group, it was found in the AMD group that ALFF value of left middle frontal gyrus was significantly lower ( t=-4.707), and that of right inferior frontal gyrus was significantly higher ( t=4.445). The results of correlation analysis showed that the ALFF value of right inferior frontal gyrus was negatively correlated with the frequency of MA use and the MA amounts used in the last month ( r=-0.396, P=0.034; r=-0.429, P=0.020). Conclusions:Abnormal brain activity intensity is found in AMD patients compared with healthy controls, with abnormalities mainly found in the prefrontal lobe, which is involved in cognitive, executive and emotion functions. The more MA is used, the more damages or alterations may exist in these regions.
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To explore the mechanism for changes in brain microstructure in long-term abstinent from methamphetamine-dependence by using the diffusion tensor imaging (DTI). Methods: A total of 26 patients with long-term abstinent methamphetamine-dependence, whose abstinence time more than 14 months, and 26 normal controls all underwent cognitive executive function tests and DTI scans. We used voxel-based analysis to compare the fractional anisotropy (FA) and mean diffusivity (MD) to obtain the abnormal brain regions of DTI parameters between the two groups. Spearman correlation analysis was used to explore the correlation between FA, MD of the brain regions with abnormal parameters and cognitive executive function tests. Results: There were no statistical differences in the cognitive executive function tests between the two groups (P>0.05). Compared with the normal control group, the long-term abstinent from methamphetamine-dependence group showed the decreased FA in the right precuneus, right superior frontal gyrus, right calcarine, left inferior temporal gyrus and the increased MD in the right triangular part of inferior frontal gyrus, right precuneus, right posterior cingulate, right middle temporal gyrus, bilateral middle occipital gyrus, left superior parietal lobule, and lobule VIII of cerebellar hemisphere. The MD values of the right middle temporal gyrus in the long-term abstinent group were negatively correlated with the number of completions within 60 seconds (r=-0.504) and within 120 seconds (r=-0.464) . Conclusion: The DTI parameters in multiple brain regions from the methamphetamine-dependence patients are still abnormal after a long-term abstinence. DTI can provide imaging evidence for brain microstructural abnormalities in long-term abstinent from methamphetamine-dependence.
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Humans , Amphetamine-Related Disorders , Anisotropy , Brain , Diffusion Tensor Imaging , MethamphetamineABSTRACT
Objective@#To investigate the changes of brain gray matter volume (GMV) and brain activity in patients with long-term methamphetamine (MA) abstinence compared with healthy controls.@*Methods@#This study included 44 abstinent MA patients and 40 demographically equivalent healthy controls. Structural magnetic resonance imaging (MRI) and resting-state functional MRI (rs-fMRI) were obtained on Siemens 3.0 T MR. Differences in GMV between abstinent MA group and control group were assessed using voxel-based morphometry (VBM) method. Within each region showed significant differences between two groups, the value of the fractional amplitude of low frequency fluctuation (fALFF) was calculated using the rs-fMRI data. Differences of fALFF between groups were also evaluated. Furthermore, partial correlation coefficients adjusted for age, years of education, smoking and drinking were calculated in the abstinent MA group to assess associations between the mean GMV and fALFF values in significant clusters and variables of MA use and abstinence.@*Results@#Compared with controls, abstinent MA group showed increased GMV in the right cerebellum crus and decreased GMV in the right calcarine. While fALFF values within bilateral cerebellum crus in abstinent MA patients were significantly increased. Moreover, GMV of the left cerebellar crus was positively correlated with the withdrawal time among abstinent MA patients.@*Conclusions@#Both structural and functional abnormalities were found in abstinent MA patients even after long-term abstinence. The positive correlation between GMV of left cerebellum crus and abstinent duration suggested that prolonged abstinence may be beneficial to brain recovery. The fALFF of the right calcarine was increased even with decreased GVM in the abstinent MA group. It indicates that the brain activity of this area is increased, which may imply that drug cue-induced craving is significant among methamphetamine patients even after long-term abstinence.
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Objective To investigate the changes of brain gray matter volume (GMV) and brain activity in patients with long?term methamphetamine (MA) abstinence compared with healthy controls. Methods This study included 44 abstinent MA patients and 40 demographically equivalent healthy controls. Structural magnetic resonance imaging (MRI) and resting?state functional MRI (rs?fMRI) were obtained on Siemens 3.0 T MR. Differences in GMV between abstinent MA group and control group were assessed using voxel?based morphometry (VBM) method. Within each region showed significant differences between two groups, the value of the fractional amplitude of low frequency fluctuation (fALFF) was calculated using the rs?fMRI data. Differences of fALFF between groups were also evaluated. Furthermore, partial correlation coefficients adjusted for age, years of education, smoking and drinking were calculated in the abstinent MA group to assess associations between the mean GMV and fALFF values in significant clusters and variables of MA use and abstinence. Results Compared with controls, abstinent MA group showed increased GMV in the right cerebellum crus and decreased GMV in the right calcarine. While fALFF values within bilateral cerebellum crus in abstinent MA patients were significantly increased. Moreover, GMV of the left cerebellar crus was positively correlated with the withdrawal time among abstinent MA patients. Conclusions Both structural and functional abnormalities were found in abstinent MA patients even after long?term abstinence. The positive correlation between GMV of left cerebellum crus and abstinent duration suggested that prolonged abstinence may be beneficial to brain recovery. The fALFF of the right calcarine was increased even with decreased GVM in the abstinent MA group. It indicates that the brain activity of this area is increased, which may imply that drug cue?induced craving is significant among methamphetamine patients even after long?term abstinence.
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OBJECTIVE： To study the improvement effects of Bee venom（BV） plastics on experimental cerebral thrombosis in rats. METHODS： Totally 96 SD rats were randomly divided into sham operation group （normal saline）， model group （plastics blank matrix）， Nimodipine group （positive drug， 4.00 mg/kg） and BV plastics low-dose， medium-dose， high-dose groups （1.67， 3.33， 6.67 mg/kg）， with 16 rats in each group. Rats in sham operation group and Nimodipine group were given medicine intragastrically， while rats in model group and BV plastics groups were given medicine by transdermal smearing. After 5 days of continuous administration， the experimental cerebral thrombosis model was established by ligating the right external carotid artery and pterygomandibular artery， and injecting compound thrombus inducer into the internal carotid artery. The wet mass ratio of right brain to left brain was measured to investigate the degree of brain edema on the infarcted side. The content of Evans blue （EB） in the left and right hemispheres of rats was determined by ultraviolet spectrophotometry to investigate the cerebral vascular permeability. Blood rheology and coagulation function indicators of rats were measured. The pathological changes of brain tissue in rats were observed by HE staining， and the number of survival neuron cells was counted. RESULTS： Compared with the indexes of sham operation group， the cerebral thrombosis model was established successfully. Compared with model group， the area of blue staining in the right brain （infarcted side） of rats in BV plastics groups was significantly reduced， and the right brain/left brain wet mass ratio and the content of EB in the right brain tissue were significantly reduced （P＜0.05 or P＜0.01）. The whole blood viscosity and Casson viscosity of rats in BV plastics groups， and the plasma viscosity of rats in BV plastics medium-dose and high-dose groups decreased significantly （P＜0.01）. PT and APTT of rats were prolonged significantly in BV plastics medium-dose group （P＜0.01）. The pathological changes of brain tissue in rats in BV plastics groups were significantly alleviated. The arrangement of neuron cells was more orderly， the shape and structure of cells were clear， the nucleolus was clear， the membrane was intact， and the number of survival neuron cells was significantly increased （P＜0.01）. CONCLUSIONS： BV plastics can alleviate brain edema， inhibit cerebral vascular permeability， improve hemorheology and coagulation function indicators of rats after the formation of cerebral thrombosis， and alleviate nerve cell injury after ischemia.
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Objective:To explore the characteristics of brain structure in patients with long-term withdrawal of methamphetamine-dependence.Methods:A total of 44 patients with withdrawal of methamphetamine-dependent for more than 14 months were recruited,who met the diagnostic criteria for substance dependence in the fifth edition of the American Mental Disorders Diagnostic and Statistical Manual (DSM-Ⅴ),and 40 healthy subjects were used as the control.In addition to the general scale of drug-relevant survey,the subjects received the 3.0T magnetic resonance high-resolution scan.The voxel-based morphometric measurements for the subject's brain gray volume were conducted.Results:There was no significant difference in age,education,smoking and alcohol consumption between the methamphetamine-dependent withdrawal group and the control group (P＞0.05).The volumes for the bilateral cerebellum,the left side of temporal gyrus and the right side of the lingual gyrus in the methamphetamine-dependent withdrawal group were increased than those in the control group.The volumes for the bilateral lingual gyrus and bilateral cuneus in the methamphetamine-dependent withdrawal group were decreased than those in the control group.The volumes of left of cuneus and cerebellum were positively correlated with the duration of abstinence.Conclusion:After long-term abstinence,although the patients still show abnormal brain structure,their behavior and cognitive function is improved.The cerebral nerve structural is recovered from long-term abstinence.
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Objective To research the protective effect of Ento-Ⅰagainst cerebral ischemia-reperfusion injury in rats,and to evaluate its analgesic and anticoagulating effects in mice. Methods The ischemic model was established with line embolism to block the middle cerebral artery of male rats. The 56 rats were randomly assigned into 7 groups of sham-operation,blank-matrix,nor? mal saline,Ento-Ⅰplastic of 3 doses(6.67,3.33,1.67 mg/kg),and ozagrel sodium(8.3 mg/kg,ip). The effect of Ento-Ⅰplastic on anti-cerebral ischemia was measured by nervous function scores and the areas of cerebral infarction were determined by TTC staining for the calculation of cerebral infarction rates. The analgesic effect of Ento-Ⅰplastic was determined with acetic acid-induced twisting experiment. Sixty KM mice were randomly allocated into blank-matrix,aspirin,aspirin-plastic,and Ento-Ⅰplastic of 3 doses(5,10 and 20 mg/kg),the number of mouse twisting were recorded right after intraperitoneal injection of 0.7%acetic acid solution at the time of 1 h after the last administration. Moreover,the anticoagulant activity of Ento-Ⅰplastic was tested by glass capillary method. Re?sults The results of acetic acid-induced twisting experiment displayed that Ento-Ⅰplastic of all 3 dose groups(5,10 and 20 mg/kg) could significantly reduce the number of body torsion and increase the inhibitory rates of twisting,compared with that of blank matrix group(the inhibitory rates of twisting for 3 dose groups were 21.79%,48.89%,and 56.15%,respectively),with dose-response man?ner. According to the results of glass capillary test,the clotting time of mouse blood could be significantly prolonged by mid-(10 mg/kg)and low-dose(5 mg/kg)of Ento-Ⅰplastic with corresponding clotting time of(155.20±54.19)s and(155.80±73.84)s,compared with normal saline group at(92.10 ± 24.61)and blank-matrix group at(80.40 ± 48.09,P<0.05). The experiment results of the isch?emia-reperfusion injury by line embolism method in rats exhibited that Ento-Ⅰplastic in mid-dose(3.33 mg/kg)could significantly re?duce the neurological scores after 24 h of reperfusion injury,from(2.33 ± 0.52)of normal saline group to(1.00 ± 0.00)of mid-dose group(P<0.01). The results from TTC staining revealed that the cerebral infarction rates of normal saline group and blank-matrix group were(24.89±7.24)%and(27.72±7.89)%,respectively,whereas those of 6.67 mg/kg and 3.33 mg/kg group of Ento-Ⅰplastic were(14.01±2.65)%and(14.73±4.94)%,respectively. Compared to the 2 negative-control groups,both the high-and mid-dose of Ento-Ⅰplastic could significantly reduce the cerebral infarction rates after ischemic reperfusion injury in rats (P<0.01). Conclu?sion Ento-Ⅰplastic demonstrates strong analgesic and anticoagulant effects,and could substantially reduce the neurological scores and reduce cerebral infarction rates for ischemia-reperfusion injured rats. These are likely to be the mechanism of action for Ento-Ⅰplastic realizing its anti-cerebral ischemia effect.
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Susceptibility weighted imaging (SWI) is a magnetic resonance technology with a high resolution, three-dimensional gradient echo and fully velocity compensated sequence. It is also sensitive to substance with different magnetisability. Based on the quantitative reconstruction of SWI, quantitative susceptibility mapping (QSM) has been used in monitoring the change of intravenous iron, calcium, microbleeds and oxygen content. This article summarizes principle of QSM and the latest progress of QSM application in the diseases of central nervous system.