ABSTRACT
The 18 kDa translocator protein (TSPO), previously known as the peripheral benzodiazepine receptor, is predominately localized to the outer mitochondrial membrane in steroidogenic cells. Brain TSPO expression is relatively low under physiological conditions, but is upregulated in response to glial cell activation. As the primary index of neuroinflammation, TSPO is implicated in the pathogenesis and progression of numerous neuropsychiatric disorders and neurodegenerative diseases, including Alzheimer's disease (AD), amyotrophic lateral sclerosis (ALS), Parkinson's disease (PD), multiple sclerosis (MS), major depressive disorder (MDD) and obsessive compulsive disorder (OCD). In this context, numerous TSPO-targeted positron emission tomography (PET) tracers have been developed. Among them, several radioligands have advanced to clinical research studies. In this review, we will overview the recent development of TSPO PET tracers, focusing on the radioligand design, radioisotope labeling, pharmacokinetics, and PET imaging evaluation. Additionally, we will consider current limitations, as well as translational potential for future application of TSPO radiopharmaceuticals. This review aims to not only present the challenges in current TSPO PET imaging, but to also provide a new perspective on TSPO targeted PET tracer discovery efforts. Addressing these challenges will facilitate the translation of TSPO in clinical studies of neuroinflammation associated with central nervous system diseases.
ABSTRACT
Objective To investigate the imaging appearances of esophageal tuberculosis.Methods 5 cases of esophageal tuberculosis proved by pathology were retrospectively analyzed.There were 2 male and 3 female patients aged between 24 and 36 years median age 29 years. All cases were undergone esophageal barium examination, CT scan and gastroscopy. The surgical resection of the tumor was complemented in one case.Results Esophageal barium contrast study showed: the location of lesions at upper, middle and low esophagus in 1,3 and 1 cases respectively. The X-ray features included filling defect in 2 cases, centripetal strictures in 2 cases, intraluminal barium patch in 1 case, extramural irregular fistulous formation in 1 case, mucosa destruction in 2 cases and mucosa flattened or disappeared in 3 cases. On chest CT, bronchiectasis in the posterior basal segment of left inferior lung in 1 case, enlargement of right hilum of lung and small nodule in the right chest wall in 1 case, irregular thickening in the wall of inferior oesophagus in 1 case, pleural adhesion in 1 case were showed, and the other two were normal. The accurate diagnosis was confirmed only in 2 patients preoperation.Conclusion Esophageal tuberculosis extent is not of imaging characteristics, its diagnosis should be in combination with clinical data.
ABSTRACT
Objective To assess the overall diagnostic value of computed tomography pulmonary angiography (CTPA) in patients with suspected pulmonary embolism with the pulmonary angiography as the gold standard.Methods A search in Cochrane Library,PubMed,OVID,and China National Knowledge Infrastructure (CNKI) was performed to identify relevant English and Chinese-language articles from 01/01/1992 to 01/01/2003 (English) and from 01/01/1994 to 01/01/2003 (Chinese),respectively.Criteria for inclusion were established based on validity criteria for diagnostic research published by the Cochrane Methods Group on Screening and Diagnostic Tests.Subsequently,the characteristics of the included articles were appraised and extracted.Statistical analysis was performed employing Meta-Test version 0.9.Heterogeneity of the included articles was tested,which was used to select proper effect model to calculate pooled weighted sensitivity and specificity.Summary Receiver Operating Characteristic (SROC) curve was performed and the area under the curve (AUC) was calculated.Finally,sensitivity analysis was performed.Results Ten of 407 retrieved articles were included,with a total of 855 patients.The reported sensitivity of CTPA ranged from 0.57 to 1.00,and specificity ranged from 0.78 to 1.00.The pooled weighted sensitivity and specificity for CTPA with 95% confidence interval (95% CI) after correction for standard error were 0.84 (0.73,0.91) and 0.91 (0.87,0.94),respectively.The AUC of SROC was 94.95%. Sensitivity analysis demonstrated no disproportionate influences of individual study.Conclusion CTPA has a highly accurate sensitivity and specificity with a strong ROC curve making it an alternative non-invasive method of pulmonary angiography in the diagnosis of PE.