Objective:To explore the distribution and clearance of 99mTc labeled diethylenetriamine pentaacetic acid(99mTc-DTPA)in different brain regions of adult rats after administration through brain extracellular space(ECS)pathway.Methods:After the injection of a volume of 2 μL and radioactive activity of about 3.7 MBq(100 μCi)of 99mTc-DTPA into the caudate nucleus and thalamus of SD rats through stereotactic positioning of rat brain,the single photon emission computed tomography/computed tomography(SPECT/CT)for small animals was used for imaging at different time points,and the dyna-mic distribution and clearance of the tracer in the whole body were observed continuously.The SD rats were injected with 99mTc-DTPA into thalamus and caudate nucleus respectively for biological distribution in vivo.They were put to death 4 h later.Their blood and urine were collected.The brain,cerebellum,heart,liver,spleen,lung,and kidney were taken and weighed by γ counter to measure its radioactivity.Results:SPECT/CT imaging results showed that after 99mTc-DTPA was administered through brain ECS,the radioactivity was concentrated in the brain,kidney and bladder.The tracer administered to the left caudate nucleus was preferentially drained to the right cerebellum,while the tracer administered to the right caudate nucleus was preferentially drained to the left cerebellum.There was a phenomenon of"con-tralateral cerebellar dominant drainage"in the caudate nucleus.The thalamic area preferentially drained to the ipsilateral cerebellum after administration.Four hours after administration via ECS,high radioac-tive uptake appeared in urine,cerebellum and brain,followed by blood and kidney.The radioactive up-take values of heart,liver,spleen and lung were low,which were mainly excreted through urinary sys-tem.Conclusion:Intracerebral ECS administration is a promising method of administration,but there are significant differences in distribution and clearance in different brain regions.This study further ex-pands the content and significance of"ECS regions",and also provides an important theoretical founda-tion for the treatment of encephalopathy and the research of new drugs through brain ECS in the future.

Objective:To explore the distribution and clearance of 99mTc labeled diethylenetriamine pentaacetic acid(99mTc-DTPA)in different brain regions of adult rats after administration through brain extracellular space(ECS)pathway.Methods:After the injection of a volume of 2 μL and radioactive activity of about 3.7 MBq(100 μCi)of 99mTc-DTPA into the caudate nucleus and thalamus of SD rats through stereotactic positioning of rat brain,the single photon emission computed tomography/computed tomography(SPECT/CT)for small animals was used for imaging at different time points,and the dyna-mic distribution and clearance of the tracer in the whole body were observed continuously.The SD rats were injected with 99mTc-DTPA into thalamus and caudate nucleus respectively for biological distribution in vivo.They were put to death 4 h later.Their blood and urine were collected.The brain,cerebellum,heart,liver,spleen,lung,and kidney were taken and weighed by γ counter to measure its radioactivity.Results:SPECT/CT imaging results showed that after 99mTc-DTPA was administered through brain ECS,the radioactivity was concentrated in the brain,kidney and bladder.The tracer administered to the left caudate nucleus was preferentially drained to the right cerebellum,while the tracer administered to the right caudate nucleus was preferentially drained to the left cerebellum.There was a phenomenon of"con-tralateral cerebellar dominant drainage"in the caudate nucleus.The thalamic area preferentially drained to the ipsilateral cerebellum after administration.Four hours after administration via ECS,high radioac-tive uptake appeared in urine,cerebellum and brain,followed by blood and kidney.The radioactive up-take values of heart,liver,spleen and lung were low,which were mainly excreted through urinary sys-tem.Conclusion:Intracerebral ECS administration is a promising method of administration,but there are significant differences in distribution and clearance in different brain regions.This study further ex-pands the content and significance of"ECS regions",and also provides an important theoretical founda-tion for the treatment of encephalopathy and the research of new drugs through brain ECS in the future.

OBJECTIVE: To explore the relationship among loneliness at workplace, job burnout, and turnover intention in prison policemen. METHODS: A convenience sampling method was used to select a total of 290 prison policemen officers as the study subjects in Guangxi Zhuang Autonomous Region. The Workplace Loneliness Scale, Job Burnout Scale and Turnover Intention Scale were used to investigate the loneliness at workplace, job burnout and turnover intention respectively.RESULTS: The scores of turnover intention of 31-40 age group were higher than that of 41 or over age group(P<0.01). The scores of turnover intention in the length of service 1-5 years group and 6-10 year length of service group were higher than that of length of service over 16 years or more(P<0.05). The scores of turnover intention of section group policemen were higher than that of division group(P<0.05). The loneliness in the workplace was positively correlated with job burnout[Spearman rank correlation coefficient(r_S)=0.343, P<0.01], and turnover intention(r_S=0.392, P<0.01), and job burnout was positively correlated with turnover intention(r_S=0.408, P<0.01). Job burnout was the intermediate variable between loneliness in the workplace and turnover intention with a mediating effect rate of 60.2%. CONCLUSION: The job burnout of prison policemen plays a partial role in mediating the influence of loneliness at workplace on turnover intention.

Objective To investigate diagnostic magnetic resonance imaging features of orbital Langerhans cell histocytosis (LCH)and improve its diagnostic accuracy.Methods The symptoms and image data of fourteen histophathology verified orbital LCH cases are reviewed and analyzed.Results Nine patients had swollen eyelids,accompanying with symptoms of inflammation, esphthalmos and orbital masses.One case had cough symptom and another had diabetes insipidus.Of these fourteen cases,seven occurred in right orbital,six occurred in left orbital and one involved bilateral orbital.As to the location of LCH,six cases located in super-lateral wall of the orbit,five cases located in lateral wall of the orbital,and three cases located in roof of orbital.On MRI, thirteen cases lesions show hypo or iso signal intensity on T1 WI,and eleven cases lesions show heterogeneous hyper or iso signal in-tensity on T2 WI.The lesions of eosinophilic granuloma has clear border,which differentiate it from other types.After contrast en-hancement,MR imaging showed marked inhomogeneous enhancement.Conclusion MRI is the primary modality in diagnosing of or-bital LCH,clearly and accurately manifesting the extent of orbital LCH.It will be helpful to diagnose LCH timely if combining with clinical data.MR could provide reliable information for making surgical operation and treatment plan.