L-dopa (l-3,4-dihydroxyphenylalanine)-induced dyskinesia (LID) is a debilitating complication of dopamine replacement therapy for Parkinson's disease. The potential contribution of striatal D₂ receptor (D₂R)-positive neurons and downstream circuits in the pathophysiology of LID remains unclear. In this study, we investigated the role of striatal D₂R⁺ neurons and downstream globus pallidus externa (GPe) neurons in a rat model of LID. Intrastriatal administration of raclopride, a D₂R antagonist, significantly inhibited dyskinetic behavior, while intrastriatal administration of pramipexole, a D₂-like receptor agonist, yielded aggravation of dyskinesia in LID rats. Fiber photometry revealed the overinhibition of striatal D₂R⁺ neurons and hyperactivity of downstream GPe neurons during the dyskinetic phase of LID rats. In contrast, the striatal D₂R⁺ neurons showed intermittent synchronized overactivity in the decay phase of dyskinesia. Consistent with the above findings, optogenetic activation of striatal D₂R⁺ neurons or their projections in the GPe was adequate to suppress most of the dyskinetic behaviors of LID rats. Our data demonstrate that the aberrant activity of striatal D₂R⁺ neurons and downstream GPe neurons is a decisive mechanism mediating dyskinetic symptoms in LID rats.
Rats ; Animals ; Levodopa/toxicity* ; Dopamine ; Parkinsonian Disorders/drug therapy* ; Oxidopamine ; Dyskinesia, Drug-Induced ; Corpus Striatum/metabolism* ; Neurons/metabolism* ; Receptors, Dopamine D2/metabolism* ; Antiparkinson Agents/toxicity*

Objective To evaluate the value of procalcitonin(PCT) and endotoxin(ET) in early diagnosis and prognosis in critically illness patients with sepsis.Methods A total of 104 cases with suspected sepsis were prospectively collected in this study from February 2015 to October 2016 in ICU.There were 31 cases of systemic inflammatory response syndrome (SIRS group),30 cases of sepsis 24 cases of severe sepsis and 19 cases of septic shock.Prognosis was observed in patients with sepsis discharged,57 cases were survival (survival group) while 16 cases were dead (death group).The level of PCT and ET and the clinical characteristics were recorded,The the ROC curve was applied to evaluate the discriminative power of variables.Results The levels of PCT,APACHE-Ⅱ score,ET of cases with sepsis,severe sepsis and septic shock were significantly higher than those in SIRS group(P<0.05).The PCT and APACHE-Ⅱ scores were elevated by the severities of disease (P<0.05).ROC curve analysis showed that,the sensitivity of PCT value was 82.2% and specificity was 87.5%.PCT and APACHE-Ⅱ scores were higher in the death group (P<0.05),whereas there was no significant difference on ET between the two groups (P>0.05).ROC curve showed that AUC of PCT was 0.867,which was significantly higher than that for APACHE-Ⅱ score (AUC=0.762) (P>0.05).Conclusion Compared with APACHE-Ⅱ score and ET,PCT can help clinicians to early diagnose and treat cases with sepsis.

The fluorescence of Rhodamune B could be quenched by the manner of photo-unduced electron transfer wuth Cu2-x Se nanopartucles as the energy receptor and Rhodamune B as the energy donor. However, L-cysteune was capable of recoverung the fluorescence of Rhodamune B, and the fluorescence untensuty was proportuonal to the concentratuons of L-cysteune. Based on that, a novel method for detectung L-cysteune was establushed. After muxung L-cysteune and Rhodamune B pretreated by Cu2-x Se nanopartucles at pH 4. 6 and 30℃ for 2 mun, a lunear relatuonshup was obtauned between the fluorescence untensuty of Rhodamune B at 575 nm and the concentratuons of L-cysteune un the range of 2. 5 ×10-7-1. 1 ×10-6 mol/L. Thus method was used un the determunatuon of L-cysteune wuth a detectuon lumut (3σ/k) of 5. 5×10-8 mol/L. The common amuno acuds presented luttle unterference for the L-cysteune detectuon.

Objective To explore a new index for reflecting the topological information of brain functional networks in patients at high risk of Alzheimer disease using characteristics of resting-state functional connectivity strengths(FCS) in patients with amnestic mild cognitive impairment(aMCI). Methods Thirty-one aMCI patients and 42 age, gender and years of education matched normal controls were enrolled between September 2009 and April 2011 in this study. The resting-state functional MRI (rs-fMRI) data of all participants were acquired and preprocessed. Then the whole-brain functional connectivities were constructed for exploring the distribution characteristics of hub regions which had higher FCS values. Using two-sample t test to compare group differences in age, years of education and each neuropsychological assessment. In addition, using Chi-squared test to compare group differences in gender. Group differences in FCS values were analyzed by general linear model. Finally, correlation analyses were used to evaluate the relationships between the FCS values of the brain regions with group differences and behavioral scores in aMCI patients. Results The hub regions of the functional networks in the aMCI patients were mainly located in the association cortices such as the precuneuses, posterior cingulate cortices, medial prefrontal cortices, angular gyri, superior occipital gyri, fusiform gyri and lingual gyri. The distribution models in the aMCI patients were consistent with those in the normal controls. However, the FCS values of these brain regions were significantly lower in the aMCI patients than those in the normal controls. In comparison to the normal controls, the aMCI patients had significantly decreased FCS values in the bilateral fusiform gyri, lingual gyri, superior occipital gyri, left middle occipital gyrus and postcentral gyrus (the cluster was 389, 230, 187 and 107 voxels, respectively;P<0.05, respectively), and they had decreased trends of FCS values in the bilateral posterior cingulate cortices and right insulas. The correlation analysis with uncorrected conditions showed that the FCS values of the left postcentral gyri were correlatid with the clock drawing test (CDT) scores (r=0.436, P=0.026). Conclusions aMCI mainly attacks the hub regions of brain functional networks. The changes of functional connectivities in aMCI may reflect the early pathophysiologic alterations of AD.

Purpose Two kinds of forward conditional reasoning including modus ponens (MP) and denial of the antecedent (DA) are the most common deductive reasoning in daily life. The present study aimed to explore the difference between the two neural machanisms. Materials and Methods Three kinds of tasks including MP, DA, and baseline were administrated to 14 undergraduates [7 males and 7 females, mean age (23.4±1.3) years] by using functional magnetic resonance imaging (fMRI) technique. fMRI data was analyzed. Results The reaction times were significantly slower for MP and DA than that of BS (P<0.001), while the effect was not significant for accuracy. In contrast to baseline, both MP and DA tasks activated the left inferior frontal cortex (BA 9), inferior parietal lobule (BA 40), and postcentral gyrus. Bilateral caudate significant activation was found in MP task when compared with DA, whereas the frontal, parietal, occipital lobe and anterior cingulate cortex were acivated more in the DA than in MP task. Conclusion Both forward conditional reasoning of MP and DA commonly activate the left frontoparietal cortex, while significant dissociations can be seen in the regions of caudate and bilateral frontal, parietal and occipital. These results firstly demonstrates the different neural mechanism underlying the two forward conditional reasoning, which might help to further uncover the brain mechanism of conditional reasoning.

By taking American Penn State University Medical Center as an example, the paper introduced the current American radiology resident education training situation and elaborated the radiology resident rotation system, multiform teaching model and academic research training. Medical education in American sheds light on how to reasonably arrange rotation, mobilize students' subjective initiative and improve scientific research ability, which radiology resident medical education in China can draw lessons from.

ObjectiveTo explore the normal range of the volume of internal capsules in Chinese adults of the Han nationality and its relationship with age,body habitus,and craniocerebral volume.Methods One thousand healthy volunteers (age range =18 to 80 years) were divided into 5 groups according to their age;Group A ( 18 to 30 years old),group B (31 to 40 years),group C (41 to 50 years),group D (51 to 60 years),and group E (61 to 80 years).Each group consisted of 100 males and 100 females.MR imaging was performed in all of the volunteers using T1 weighted three-dimensional nagnetization prepared rapid acquisition gradient echo sequence. After three dimension data reconstruction,the volumes of bilateral internal capsules were manually measured. The volumes of bilateral internal capsules were compared by paired sample t test.The internal capsule volumes were compared between male and female by independent sample t test,and the differences among 5 age groups were compared by one-way ANOVA.The relationship between the volumes of internal capsule and age,body habitus or cerebral volume were analyzed using bivariate correlation.ResultsThe left and right internal capsule volumes were (2809 ± 393) and (2677 ± 343 ) mm3 respectively.The left internal capsule volumes were significantly larger than that of right (t =12.078,P ＜ 0.05 ).The left and right side of internal capsule volumes in male were (2863 ± 396) and (2744 ±358) mm3 respectively,and (2754 ±385) and (2609 ±314) mm3 in female.The left and right internal capsule volumes were larger in males than in female (t =1.982,2.851 ;P ＜ 0.05 ).The left internal capsule volume of the 5 age groups were ( 3273 ± 361 ),( 2943 ± 299 ),( 2777 ± 255 ),( 2607 ± 199 ),(2444 ±213) mm3,and the right were (2993 ± 361 ),(2814 ± 270),(2682 ± 239),(2543 ± 219),(2351 ±210) mm3.There were significant differences among 5 age groups between left and right internal capsule volume ( F =55.244,34.493 ; P ＜ 0.05 ).There was significant negative correlation between the volume of left and right internal capsule and age ( r =- 0.718,- 0.637 ; P ＜ 0.05 ).Conclusions1.5 T MR scanner can be used to accurately measure the internal capsule volumes.There is a significant negative correlation between age and internal capsule volumes.

ObjectiveTo measure the volume of thalamus in 1000 healthy Chinese Han nationality adults,and to analyze the relationship between thalamic volume and age,sex,weight and cerebral volume,to provide reliable data for the construction of database of Chinese adults' digital standard brain.Methods Totally 1000 healthy Chinese adults of Han nationality aged from 18 to 80 years were recruited.They were divided into 5 groups by age:18-30,31-40,41-50,51-60 and 61-80 years.Each group included 100 males and 100 females.Brain images were obtained on a 1.5 T MR,and the outline of thalami was drawn with Aquariusws software.Then the thalamic volume was calculated automatically.The volumes of left and right thalamus were compared by paired sample t-test.Thalamic volumes of the same side were compared between males and females by independent sample t-test.And thalamic volumes of different age groups were compared by one-way ANOVA.The relationships between thalamic volume and age,sex,weight and cerebral volume were analyzed respectively.ResultsThe males' standardized volumes of left and right thalamus of healthy Chinese Han nationality adults were (5776 ± 780),(5655 ± 759) mm3,and they were (5464 ±573 ),(5360 ± 542) mm3 for female.The males' thalamic volume was more than the females' on the same side ( t =2.245,2.200,P ＜ 0.01 ).The left thalamic volumes of various age groups were ( 6180 ± 534 ),(6047 ± 562 ),( 5426 ± 471 ),( 5552 ± 526 ),( 4866 ± 552 ) mm3,respectively,while the right thalamic volumes of the 5 groups were ( 6069 ± 532 ),( 5895 ± 539 ),( 5357 ± 480 ),( 5396 ± 445 ),( 4791 ± 558)mm3,respectively.There were statistically significant difference among the 5 groups( F =165.686,165.235,P ＜ 0.01 ).The left and right thalamic volume were all negatively correlated with age ( r =- 0.633,-0.645,P ＜ 0.05 ).ConclusionsWith high resolution 1.5 T MR scanner,grey matter and white matter can be depicted clearly and the outline of thalamic can be discriminated specifically.It is useful for the measurement of thalamic volume and scientific data to build Chinese adults' digital standard brain.

Objective To explore the normal range of the caudate nucleus' volume in Chinese adults of the Han nationality and provide morphological data for the construction of database for Chinese Standard Brain.Methods This was a clinical multi-center study.One thousand Chinese healthy volunteers (age range=18 to 70)recruited from 16 hospitals were divided into 5 groups,i.e.,Group A(age range=18 to 30),B(age range=31 to 40),C(age range=41 to 50),D(age range=51 to 60),and E(age range=61 to 70).Each group contained 100 males and 100 females.All of the volunteers were scanned by MR using T1 weighted three-dimensional magnetization prepared rapid acquisition gradient echo sequence.The volume of eaudate was measured manually using 3D volume analysis software.The difierence of volumes of the eaudate between male and female were analyzed by independent sample t-test,and among age groups by ANOVA.Pearson's correlation coefficient was used to characterize the relationship between volunles and age.The differences of measurements between left and right caudate nucleus were analyzed by paired t test.Results (1)rnle mean volume of bilateral caudate nucleus in healthy Chinese adults wag(10.973±1.647)cm3.The mean volume of the the male's left and right caudate nucleus were(5.656±0.860)and (5.671±0.855)cm3 respectively,no significant differences were found between the volume of left and right eaudate nucleus(t=1.230.P>0.05).The mean volume of the the female's left and right eaudate nucleus were(5.287±0.774)and(5.331±0.766)cm3 respectively,and the right's wag larger than the left's with significant differences(t=3.999,P<0.01);(2)Pearson correlation analysis showed a significant negative correlation between the nucleus volume and age(male and female's,left and fight)(r=-0.561,-0.568,-0.548,-0.552,P<0.05).Conclusion With high-resolution MRI and 3D volumetric analytic software(Midob),the volume of the caudate nucleus can be accurately measured,so as to provide the basic data for establishing Chinese adults' standard digital brain.and provide nomad control standards for caudate nucleus volume-related diseases.

Objective To explore the morphological characteristics of optic tracts in healthy Chinese Han adults on the high-resolution MRI and fill the database of Chinese standard brain with morphological data of optic tracts.Methods Cerebral MRI scans with T1 WI 3D MPRAGE sequence of 1000 healthy Chinese volunteers from 15 hospitals were divided into five stages, ranging in age from 18 to 70.With the technique of multi-baseline, structure and morphology of optic tracts were displayed optimally on the images with multiplanar reconstruction.Data were measured as following: transverse distance of the cisternal optic tract (TD1) and peri-crural optic tract (TD2), length from the cisternal optic tract to the peri-crural optic tract (L) ,angle between optic tract(AOT) and height of optic tract from its first segment to plane of anterior commissure (H) including H1, H2, H3, H4 and HS.The measurements of optic tracts between sexualities and among age groups were compared by anasis of covariance; those among five age groups were compared pairwisedly by least significant difference analysis (LSD); and the differences of measurements between left and right optic tracts were analyzed using paired t test.Results (1) Comparisons of optic tract structures between male and female: the mean optic tract length of male [(11.69±1.45),(11.56±1.44) mm] was significant longer than that of female [(10.58±1.29),(10.40±1.34) mm] (F=22.236, 29.703, P=0.000); the mean H1 of male [(2.56±0.28),(2.60±0.29) mm] and female [(2.57±0.31 ), (2.63±0.32) mm] were significantly different ( F =11.130,7.805, P = 0.000, 0.005).No significant differences of the other measurements were found between male and female ( P > 0.05 ).(2) Comparisons among age groups: among 5 age groups, TD1 of both sides [left TD1 :(4.64±0.51 ), (4.64±0.57), (4.55±0.58), (4.39±0.53), (4.36±0.58)mm;right TD1 :(4.84±0.53) ,(4.80±0.60), (4.77±0.65), (4.60±0.59), (4.57±0.59) mm] and the right TD2[(3.33±0.45),(3.34±0.41),(3.33±0.36),(3.23±0.38),(3.23±0.39) mm] had statistical differences ( F = 3.458, 2.735, 4.711, P = 0.008,0.028, 0.001 ).The LSD analysis found that the 50 years old group was the watershed with significant differences ( P < 0.05 ).The results also showed that the L of both sides had statistical differences among 5 age groups ( F = 14.510,14.532, P = 0.000).The LSD analysis found that the 60 years old group was the watershed with significant differences (P <0.05).Left TD2 and the H1-H5 of both sides had no significant differences among age groups ( P >0.05).(3) Comparisons of the measurements between left and right optic tracts: TD1 of bilateral optic tracts were (4.52±0.57)and(4.72±0.60) mm respectively; H1 of bilateral optic tracts were (2.56±0.30)and (2.61±0.30) mm respectively; H2 of bilateral optic tracts were (2.66±0.30)and (2.70±0.30) mm respectively; and L of bilateral optic tracts were ( 11.14±1.47 ) and ( 10.98±1.50 )mm respectively.There were significant differences in these measurements between left and right optic tracts( t =12.460, - 6.013,5.595,4.784, P = 0.000 ), while there were no significant differences in TD2, H3, H4 and H5( P > 0.05 ).Conclusions With high-resolution MR1 and 3D reconstruction, optic tract can be displayed clearly and measured accurately.There are definite differences in anterior segments of optic tracts between sexualities, sides and among ages in normal Chinese Han adults, while the posterior segments of optic tracts keep stable.Normal reference values of optic tracts in Chinese Han adults are provided to clinical practices and scientific researches, which are valuable for building of Chinese standard brain.