An Intracranial Gliosis Mimicking Neoplasm: A Dilemma.

Intracranial gliosis has no typical clinical signals or imaging characteristics. Therefore, it can be easily misdiagnosed as neoplasm. Hereby, we report a unique case of gliosis that grew outward from the surface of the brain. MRI depicted its signal and enhancement pattern similar to the cerebral gray matter. The diagnosis was confirmed by pathology and immunohistochemistry. Although it was difficult to reach a diagnosis, correlating its origin, growing pattern and MR features and knowing that gliosis can present this way may help in differentiating it from other diseases.

[In vivo labeling of rat neural progenitor cells in subventricular zone with superparamagnetic iron oxide for tracking of magnetic resonance imaging].

OBJECTIVE: To explore the feasibility of in vivo labeling of adult rat neural progenitor cells (NPCs) in subventricular zone (SVZ) with superparamagnetic iron oxide particles (SPIOs) for tracking of magnetic resonance imaging (MRI). METHODS: A total of 7 SD rats were stereotactically injected with 3 µl SPIOs (7 mg Fe/ml) into anterior horn of right lateral ventricle and then 5-bromo-2'-deoxyuridine (BrdU) was injected intraperitoneally once daily for 1 week. MRI was performed at 1, 3, 7 and 14 days post-injection. After the final MRI scan, all rats were transcardially perfused and their brains removed and fixed. The sections were processed for Prussian blue iron staining and Prussian blue plus BrdU immunohistochemical staining. RESULTS: In all experimental animals, SPIOs were predominantly located in the anterior horn of right lateral ventricle and partial SPIOs entered the ventricular system. A needle path and a distribution of SPIOs along rostral migratory stream (RMS) towards olfactory bulb (OB) were depicted at the sagittal view of T2(*)WI, moderate MR artifact was visible and SPIOs tracking NPCs were successful (success rate of 100%). The result of staining showed SPIOs labeling NPCs were effective. And the labeling rates were 75.5%, 42.3%, 23.6% in SVZ, RMS and OB respectively. CONCLUSION: Effective in vivo labeling of adult rat NPCs in SVZ with SPIOs is feasible. And dynamical migration of labeling NPCs along RMS towards OB may be visualized on MRI.

Malignant mesothelioma presenting as a giant chest, abdominal and pelvic wall mass.

Malignant mesothelioma (MM) is a relatively rare carcinoma of the mesothelial cells, and it is usually located in the pleural or peritoneal cavity. Here we report on a unique case of MM that developed in the chest, abdominal and pelvic walls in a 77-year-old female patient. CT and MRI revealed mesothelioma that manifested as a giant mass in the right flank and bilateral pelvic walls. The diagnosis was confirmed by the pathology and immunohistochemistry. Though rare, accurate investigation of the radiological features of a body wall MM may help make an exact diagnosis.

[Study of bone mesenchymal stem cells tropism for hepatic tumors and effect on the form of tumor stromal].

OBJECTIVE: To investigate the tropism capacity of the rat bone mesenchymal stem cells (BMSC) for hepatic tumors microenvironment and the effect on the form of tumor stromal. METHODS: Rat BMSC were isolated, cultured and expanded, then incubated with superparamagnetic iron oxide (SPIO) nanoparticles. Prussian blue stain was performed for showing intracellular irons. Walker-256 cells were injected into the rat livers directly to establish hepatic tumor models. The experiment was divided into two experimental groups (the group venous injected with BMSC after tumors becoming mass: tail venous injected with BMSC after MR showed the presence of tumors at 6-8 days after operation and the group venous injected with BMSC before tumors becoming mass: tail venous injected with BMSC when MR showed no presence of tumors at 3 days after operation) and one control group. To the experimental groups animals, MRI was made before venous injection of BMSC and at 5, 10, 15 days after BMSC transplantation. The rats were killed at corresponding period. The pathologic examinations were analyzed, including HE, Prussian blue stain. The expression of vascular endothelial growth factor (VEGF), CD31, von Willebrand factor (vWF) in the specimens harvested at 10 days after BMSC transplantation were detected immunohistochemically. RESULTS: Prussian blue staining of SPIO labeled BMSC demonstrated cells could be effectively labeled and the labeling efficiency was almost 90%. After BMSC transplantation, two experimental groups were showed tuberculous signal intensity loss at the margin of tumors on T(2) weighted MR images at 5, 10 days after transplantation and the signal intensity loss was not visualized at 15 days after transplantation. The control group was not observed signal intensity decrease. Prussian blue staining of histological analysis showed blue-stained iron particles distributed at the margin of tumor at 5, 10, 15 days after transplantation. Immunohistochemical examination showed that the expression of VEGF, CD31, vWF in two experimental groups at 10 days after transplantation were higher than that in the control group (F = 34.03, P < 0.01; F = 84.24, P < 0.01; F = 7.08, P < 0.05). CONCLUSION: Rat BMSC have the ability to migrate towards hepatic tumors in vivo and promote to form vascular endothelium.

[Effects of mesenchymal stem cell transplantation on growth of liver cancer: experiment with rats].

OBJECTIVE: To evaluate the effects of mesenchymal stem cell (MSC) transplantation on the growth of liver cancer. METHODS: MSCs were isolated from the bone marrows of SD rats. Walker-256 cancer cells were isolated from the cancerous ascites of rat and cultured. Forty-five SD rats were randomly divided into 3 equal groups: mixed transplantation group undergoing laparotomy and transplantation of cancer cells mixed with MSCs into the liver, MSC IV transplantation group undergoing injection of MSCs into the caudal vein, and control group undergoing only MSC transplantation into the liver. MR imaging was performed s at days 3, 6, 9 and 12 after modeling to measure the maximum cross section area of the tumor. At day 12 the rats were killed after MR imaging with their livers taken out to undergo HE staining and pathological examination. Immunohistochemistry was used to detect the expression of vascular endothelial cell growth factors (VEGF), nm23 gene, a tumor metastasis inhibiting gene, and proliferating cell nuclear antigen (PCNA), a nuclear polypeptide necessary in the DNA synthesis. RESULTS: No significant evidence of tumor formation was detected by MRI at days 3 and 6 after modeling in all rats and tumor nodules were observed since day 9. The maximum cross section areas of tumor of the mixed transplantation group and MSC IV transplantation group were significantly larger than that of the control group at days 9 and 12 (F = 4.21, P < 0.05; F = 8.52, P < 0.01). Immunohistochemistry showed that VEGF expression levels of the two study groups were both significantly higher than that of the control group (F = 9.58, P < 0.01), while the nm23 gene expression levels of the 2 study groups were both significantly lower than that of the control group (F = 4.61, P < 0.05). The PCNA expression level of the mixed transplantation group was significantly higher than that of the control group (d'((1, 0.05)) = 0.34, d'((1, 0.01)) = 0.63, P < 0.05), however, there was no significant difference in the PCNA expression level between the MSCs IV transplantation group and the control group (d'((1, 0.05)) = 0.32, d'((1, 0.01)) = 0.48, P > 0.05). There was no significant difference in the tumor apoptotic index between the 2 study groups and the control group (F = 1.25, P > 0.05). CONCLUSION: MSC transplantation increases the expression of VEGF and PCNA, while decreases the expression of nm23 gene in cancer cells, thus favoring the tumor growth.

[Anxiety disease: decreased of functional connectivity in left superior temporal gyrus (GTs) and right GTs].

OBJECTIVE: Neuronal circuits involved in the pathophysiology of anxiety are not yet fully understood. We used functional connectivity MRI to explore the characteristic of functional connectivity in anxiety disorders patient and the neural mechanism of this disease. This work was selected as an oral presentation in 2006 ISMRM. METHODS: Twenty right-handed subjects were included in this study, and were divided into two groups. The anxiety (P) group (n = 10; 7 male, mean age 42 years) consisted of patients meeting DSM-IV criteria for a principal diagnosis of anxiety disorder. The control (C) group consisted of volunteers free of psychiatric symptoms, and was matched on age and gender (n = 10; 7 male) with the panic patients. The subjects underwent noninvasive functional magnetic resonance imaging while listening actively to (1): emotionally neutral word alternating with no word as the control condition (CN, PN), and (2): threat-related words alternating with emotionally neutral word as the experimental condition (CT, PT). Each word was presented in pseudorandom order in each 16 s block of 12 words of the same type. Eight alternating blocks of neutral words were presented for about 256 s. The subject was only asked to passively listen to each word. All MRI data were obtained on a 1.5-Tesla scanner Data analysis was performed with SPM99 to find significant activations in two tasks for two groups. Based on group t-test, we chose two anatomically defined regions: left superior temporal gyrus (GTs) and right GTs. Then, based on individual t-map, the voxel with the largest t-value within two regions was taken as the subject-specific peak voxel. We define clusters based on faces and edges, but not corners, so each voxel has 18 neighbors. Subject-specific averaged time series were extracted by averaging the time series of 19 voxels. Since healthy control subjects showed no significant activation (corrected, P < 0.05) during processing of anxiety word to neutral word, region of interest during processing of neutral word to no word was used as substitution. The connectivity degree eta(i j) between the node i and the node j is used to identify the change of the functional connectivity associated with differential tasks, which calculated by using the methods that have developed by ourselves. Moreover, we just consider coherence in low-frequency (0-0.15 Hz). RESULTS: The activation brain regions have been reported in our previous work. Patients were significant different from normal controls on two experiments. The connectivity degree of left Gts and right Gts in two tasks across all subjects was calculated. Comparing during processing neutral word to blank, a significant decrease (P < 0.001) in functional degree was observed during processing of threaten word to neutral word (eta = 0.5636 for CN, eta = 0.555 for CT, eta = 0.5616 for PN, eta = 0.4926 for PT). Especially, the greater decrease connectivity degree was identified for patient group compared with normal control during threat-related words alternating with emotionally neutral word condition. The connectivity degree identifies that functional interactions change with differential task. CONCLUSION: This result suggests decreased functional connectivity among left superior temporal gyrus and right GTs during processing of anxiety word to neutral word in anxiety patients. This dysfunction may mediate the neural mechanism of this sort of disease.

[CT and pathological manifestations of intraductal papillary mucinous neoplasm of pancreas: a comparative study].

OBJECTIVE: To evaluate the diagnostic value of CT in pancreas intraductal papillary mucinous neoplasm (IPMN) by analyzing its CT feature and pathological findings. METHODS: The clinical and CT data was analyzed among 39 patients with IPMN whose diagnosis was confirmed by pathology. The CT manifestations were classified into 3 types: simple main pancreatic duct enlargement; main pancreatic duct enlargement combined with pancreatic cystic lesion; and simple pancreatic cystic lesion. The correlation between the CT types and Takada pathological types (main duct type, branch type, and mixed type) was analyzed. All the cases were pathologically classified into benign and malignant/boundary groups. Statistical tests of the difference of CT features (mural nodule, septa, size, caliber of main pancreatic duct and common bile duct) between the 2 groups were performed. RESULTS: The CT type I matched the main duct type, the CT type II mainly matched the branch type and mixed type, and the CT type III matched the branch type (P < 0.001). The probability of benign lesion was 92% with no mural nodule in the lesion, while the probability of benign lesion was only 42% with mural nodule presented (P = 0.003). In terms of the septa, there was no significant difference between benign and malignant lesions (P = 0.793). The size of malignant/boundary lesions exceeded that of benign lesions (P = 0.016). There were no significant difference in calibers of main pancreatic duct and common bile duct between the benign and malignant/ boundary groups. Without considering pathological grouping the caliber of main pancreatic duct exceeded that of the common bile duct in all the cases (P = 0.02). CONCLUSION: CT typing of IPMN well matches the pathological typing which benefits the CT diagnosis of IPMN. The caliber of main pancreatic duct usually exceeds that of common bile duct in IPMN. This feature contributes to its diagnosis.