Thrombin disrupts vascular endothelial-cadherin and leads to hydrocephalus via protease-activated receptors-1 pathway.

AIMS: Previous studies indicated that intraventricular injection of thrombin would induce hydrocephalus. But how thrombin works in this process remains unclear. Since cadherin plays a critical role in hydrocephalus, we aimed to explore the mechanisms of how thrombin acted on choroid plexus vascular endothelium and how thrombin interacted with vascular endothelial-cadherin (VE-cadherin) during hydrocephalus. METHODS: There were two parts in this study. Firstly, rats received an injection of saline or thrombin into the right lateral ventricle. Magnetic resonance imaging was applied to measure the lateral ventricle volumes. Albumin leakage and Evans blue content were assessed to test the blood-brain barrier function. Immunofluorescence and Western blot were applied to detect the location and the expression of VE-cadherin. Secondly, we observed the roles of protease-activated receptors-1 (PAR1) inhibitor (SCH79797), Src inhibitor (PP2), p21-activated kinase-1 (PAK1) inhibitor (IPA3) in the thrombin-induced hydrocephalus, and their effects on the regulation of VE-cadherin. RESULTS: Our study demonstrated that intraventricular injection of thrombin caused significant downregulation of VE-cadherin in choroid plexus and dilation of ventricles. In addition, the inhibition of PAR1/p-Src/p-PAK1 pathway reversed the decrease of VE-cadherin and attenuated thrombin-induced hydrocephalus. CONCLUSIONS: Our results suggested that the thrombin-induced hydrocephalus was associated with the inhibition of VE-cadherin via the PAR1/p-Src/p-PAK1 pathway.

Excision of tumors in the parapharyngeal space using an endoscopically assisted transoral approach: a case series and literature review.

OBJECTIVE: Magnetic resonance imaging (MRI) provides important information regarding tumors in the parapharyngeal space (PPS), revealing their origin, whether they are benign or malignant, and their relationships with surrounding structures. METHODS: Twelve tumors in the PPS were completely excised using an endoscopically assisted transoral approach (EATA). The MRI features were analyzed. RESULTS: Ten pleomorphic adenomas confirmed on postoperative pathological examination had the parotid pedicle sign. A fat space between the tumor and parotid gland may distinguish such a tumor from a tumor arising from a minor salivary gland in the prestyloid space and a tumor arising from the deep lobe of the parotid gland. Both the jugular vein and carotid artery were displaced posteriorly in all 10 cases of pleomorphic adenomas. The principal features of the two schwannomas confirmed on postoperative pathological examination were separation of the internal carotid artery and internal jugular vein and anteromedial displacement of the internal carotid artery, suggesting that the tumors originated in the poststyloid space. In this review, 95 tumors were excised by the EATA in the English-language literature. CONCLUSIONS: MRI renders differential diagnosis possible. PPS tumors may be completely excised via an EATA guided by tumor features evident on preoperative MRI.

The diagnostic role of diffusion-weighted magnetic resonance imaging in hypopharyngeal carcinoma.

The aim of the present study was to assess the role of diffusion-weighted magnetic resonance imaging (DWI) and apparent diffusion coefficient (ADC) values in hypopharyngeal carcinoma. A total of 40 hypopharyngeal carcinoma tissues and 15 benign lesion tissues were retrospectively analyzed. DWI, and T1- and T2-weighted magnetic resonance imaging (MRI) was performed. The sensitivity, specificity and accuracy of conventional MRI were 97.5, 66.7, and 89.1%, respectively. The mean ADC value [diffusion sensitive factor (b)=1,000× sec/mm2) for hypopharyngeal carcinomas was (1.0285±0.0328)×10-3 mm2/sec, which was significantly lower than the mean ADC value for benign lesions [(1.5333±0.1061)×10-3 mm2/sec; P<0.001]. Receiver operating characteristic (ROC) curve analysis revealed that the area under the curve (AUC) was 0.921 while the optimal threshold for the cut-off point of the ADC was 1.075×10-3 mm2/sec. The mean ADC value of the metastatic nodes was (0.9184±0.0538)×10-3 mm2/sec, lower than the mean value for the benign nodes [(1.2538±0.1145)×10-3 mm2/sec; P=0.005]. Two groups were created according to the mean of the ADC value of hypopharyngeal carcinomas [≤(1.0285±0.0328)×10-3 mm2/sec vs. >(1.0285±0.0328)×10-3 mm2/sec]. The 2-year survival rates of the two groups were 55.6 and 100.0%, respectively (P=0.024). ADC values may aid in distinguishing hypopharyngeal carcinomas from benign lesions and differentiating metastatic lymph nodes of hypopharyngeal squamous cell carcinomas from reactive cervical lymph nodes. In conclusion, mean ADC values may be useful prognostic factors in univariate analysis of hypopharyngeal carcinoma.

Relationships between dorsolateral prefrontal cortex metabolic change and cognitive impairment in first-episode neuroleptic-naive schizophrenia patients.

The present study aimed to explore the possible associations between the dorsolateral prefrontal cortex (DLPFC) metabolites and the cognitive function in first-episode schizophrenia (FES).This study included 58 patients with FES (29 males and 29 females; mean age, 22.66 ±â€Š7.64 years) recruited from the First Affiliated Hospital, College of Medicine, Zhejiang University, and 43 locally recruited healthy controls (16 males and 27 females; mean age, 23.07 ±â€Š7.49 years). The single-voxel proton magnetic resonance spectroscopy was used to measure the levels of N-acetylaspartate (NAA); complex of glutamate, glutamine, and γ-aminobutyric acid (Glx); choline-containing compounds; and myo-inositol in the DLPFC. The ratios of metabolites to creatine (Cr) were calculated. The cognitive function was assessed by Measurement and Treatment Research to Improve Cognition in Schizophrenia Consensus Cognitive Battery (MCCB). Correlation analysis was used to assess the relationships between the DLPFC metabolites and the cognitive function.Compared with the healthy controls, the patients with FES showed significantly reduced scores in each part of the MCCB, significantly reduced NAA/Cr, and significantly increased Glx/Cr in the left DLPFC. Poor performance in verbal learning and visual learning was correlated to the reduced NAA/Cr ratio in the left DLPFC.These findings suggest that a lower NAA/Cr ratio in the left DLPFC is associated with the cognitive deficits in patients with FES, and may be an early biochemical marker for the cognitive impairment in schizophrenia.

Differentiating laryngeal carcinomas from precursor lesions by diffusion-weighted magnetic resonance imaging at 3.0 T: a preliminary study.

BACKGROUND: Diffusion-weighted magnetic resonance imaging (DWI) has been introduced in head and neck cancers. Due to limitations in the performance of laryngeal DWI, including the complex anatomical structure of the larynx leading to susceptibility effects, the value of DWI in differentiating benign from malignant laryngeal lesions has largely been ignored. We assessed whether a threshold for the apparent diffusion coefficient (ADC) was useful in differentiating preoperative laryngeal carcinomas from precursor lesions by turbo spin-echo (TSE) DWI and 3.0-T magnetic resonance. METHODS: We evaluated DWI and the ADC value in 33 pathologically proven laryngeal carcinomas and 17 precancerous lesions. RESULTS: The sensitivity, specificity, and accuracy were 81.8%, 64.7%, 76.0% by laryngostroboscopy, respectively. The sensitivity, specificity, and accuracy of conventional magnetic resonance imaging were 90.9%, 76.5%, 86.0%, respectively. Qualitative DWI analysis produced sensitivity, specificity, and accuracy values of 100.0, 88.2, and 96.0%, respectively. The ADC values were lower for patients with laryngeal carcinoma (mean 1.195±0.32×10(-3) mm(2)/s) versus those with laryngeal precancerous lesions (mean 1.780±0.32×10(-3) mm(2)/s; P<0.001). ROC analysis showed that the area under the curve was 0.956 and the optimum threshold for the ADC was 1.455×10(-3) mm(2)/s, resulting in a sensitivity of 94.1%, a specificity of 90.9%, and an accuracy of 92.9%. CONCLUSIONS: Despite some limitations, including the small number of laryngeal carcinomas included, DWI may detect changes in tumor size and shape before they are visible by laryngostroboscopy. The ADC values were lower for patients with laryngeal carcinoma than for those with laryngeal precancerous lesions. The proposed cutoff for the ADC may help distinguish laryngeal carcinomas from laryngeal precancerous lesions.

Liver transplantation in Crigler-Najjar syndrome type I disease.

BACKGROUND: Crigler-Najjar syndrome type I (CNS I) is a very rare autosomal recessive inherited disease that liver transplantation can properly deal with. METHODS: We present one case of an 18-month-old child with CNS I diagnosed by clinical findings and genetic detecting. LTx was performed 5 days after kernicterus broke out and neurological symptoms were successfully reversed. RESULT: Magnetic resonance imaging and magnetic resonance spectroscopy showed encouraging results that brain pathology had a trend to return to normal in 1-year follow-up, combined with electroencephalogram and motor development estimate studies. CONCLUSIONS: Liver transplantation can cure CNS I with reversible neurological symptoms to some extent in time. Magnetic resonance spectroscopy may be a future option of predicting brain conditions and selecting suitable patients with CNS I for transplantation.

An unusual case of retrovesical ectopic prostate tissue accompanied by primary prostate cancer.

We report an unusual case of retrovesical ectopic prostate tissue in a 73-year-old man with primary prostate cancer. The man's prostate-specific antigen was 24.66 ng/ml.Transabdominal ultrasonography, pelvic computed tomography,and pelvic magnetic resonance imaging demonstrated a heterogeneous 8.5 × 8.0 × 7.0 cm mass in contact with the posterior wall of the urinary bladder. The patient underwent a retropubic radical prostatectomy and resection of tumor. Pathological examination of prostate revealed a prostatic adenocarcinoma, Gleason score of 4 + 5 = 9, and the retrovesical tumor was confirmed to be a benign prostate tissue.

[Value of 3D-DCE MRA in diagnosis of cavernous transformation of portal vein].

OBJECTIVE: To evaluate three dimensional dynamic contrast-enhanced magnetic resonance angiography (3D-DCE MRA) in diagnosis of cavernous transformation of portal vein (CTPV). METHODS: Twenty-four patients with CTPV underwent 3D-DCE MRA examinations and the reconstructed images were retrospectively analyzed. A series of clinical, laboratory and imaging studies were performed on all these cases. Among all cases 14 underwent operations and 2 with hepatocellular carcinoma complicated portal thrombosis received transhepatic artery chemoembolization. RESULT: The CTPA was located in the main trunk in 10 cases, in both the main trunk and left/right branches in 8, and in left or right branches of the portal vein in 4. In the remaining 2 cases CTPA was located at the level of superior mesenteric vein. MRA revealed multiple circuitous collateral veins striding over obstruction to extend into the liver in 9 cases,and in 7 it simultaneously showed streaky or dot-like low signal intensities representing thrombi in the extensively dilated network of portal system. MRA did not clearly demonstrate the structure of the portal vein but only showed multiple sinuous network of venous collaterals strangling together in 6 cases. In 15 cases it also showed the route and distribution of multiple hepatofugal venous collaterals. CONCLUSION: 3D-DCE MRA can provide adequate information about the site and severity of CTPA.

[Clinical value of three-dimensional dynamic contrast-enhanced MR angiography in diagnosis of angiostenosis after liver transplantation].

OBJECTIVE: To evaluate the clinical application of three-dimensional dynamic contrast-enhanced MR angiography (3D DCE MRA) in diagnosis of angiostenosis after liver transplantation. METHODS: Twenty recipients of liver transplantation underwent 3D DCE MRA examination. The blood vessel rating grades were accessed and the relative diameter of vascular anastomosis was measured; and the results were compared with those of US or DSA examination. RESULTS: Satisfactory angiography images were obtained in all cases by 3D DCE MRA, including 11 cases with normal and mild stenosis, 5 with moderate and 4 with severe stenosis in hepatic artery. Except one case in which 3D DCE MRA showed severe stenosis but DSA showed moderate stenosis, the results of MRA were all consistent with those of US or/and DSA in the stenosis degree of the portal vein, hepatic vein and the postcava. CONCLUSION: 3D DCE MRA is an effective technique to evaluate the degree of angiostenosis after liver transplantation.

Cortical language activation in aphasia: a functional MRI study.

BACKGROUND: Functional neuroimaging has been used in neurolinguistic research on normal subjects and on patients with brain damage. This study was designed to investigate the differences of the neural basis underlying language processing between normal subjects and aphasics. METHODS: Functional magnetic resonance imaging (fMRI) was used to map the language network in 6 normal subjects and 3 patients with aphasia who were in the stage of recovery from acute stroke. The participants performed a word generation task during multi-slice functional scanning for the measurement of signal change associated with regional neural activity induced by the task. RESULTS: In normal subjects, a distributed language network was activated. Activations were present in the frontal, temporal, parietal and occipital regions. In the patient group, however, no activation was detected in the left inferior frontal gyrus whether the patient had a lesion in the left frontal lobe or not. Two patients showed activations in some right hemisphere regions where no activation appeared in normal subjects. CONCLUSIONS: fMRI with word generation task is feasible for evaluating language function in aphasic patients. Remote effect of focal lesion and functional redistribution or reorganisation can be found in aphasic patients.

MRS study on lentiform nucleus in idiopathic Parkinson's disease with unilateral symptoms.

OBJECTIVE: To investigate changes in magnetic resonance spectroscopy (MRS) of lentiform nucleus during the early stage of Parkinson's disease. METHODS: Twenty-five patients with idiopathic Parkinson disease with unilateral symptoms (IPDUS) and 25 healthy volunteers were enrolled in this study. MRS of the lentiform nucleus in each patient was taken and then concentrations of N-acetylaspartate (NAA), Creatine (Cr) and Choline (Cho) were calculated. RESULTS: Compared to that in the control, NAA/ (Cho+Cr) was significantly lower in the lentiform nucleus contralateral to symptoms and even that in the ipsilateral side in IPDUS patients (all P<0.05); while there was no difference between the two sides in the healthy volunteer (P>0.05). The ratio of NAA/(Cho+Cr) ipsilateral to the sympatomatic side of the patient was also lower than that of the control (P<0.05). CONCLUSIONS: There might be some changes with MRS on the lentiform nucleus during the early stage of idiopathic Parkinson's disease with unilateral symptom. MRS may be one of the reliable methods for early or even sub-clinical diagnosis.