Volume 88  ·   Issue 23  ·  2008

Functional magnetic resonance imaging (fMRI) can reveal the functional activity of brain tissues and cells in real time without injury, and explore various complex advanced functions of human brain, which plays a very important role in the biomedical field [1-2]. Compared with positron emission computed tomography (PET) and single photon emission computed tomography (SPECT), fMRI has the advantages of high resolution and no need to inject radioactive substances, and provides a very effective technique for studying the neurobiological mechanism of drug addiction. 　　

Psychosis refers to the general term of diseases in which the functional activities of the brain are disturbed, resulting in different degrees of mental activities such as cognition, emotion, behavior and will. The pathogenic factors are mainly: congenital heredity, personality characteristics and constitution, organic diseases of the brain, society and environment, etc. Psychosis in broad sense includes mental disorders caused by functional, organic and physical diseases, mental retardation, personality disorders and sexual psychological disorders, etc. 　　

blood oxygenation level dependent functional magnetic resonance imaging (BOLD-fMRI) is a new magnetic resonance technique developed in 1990s. It can obtain anatomical, physiological and pathological information while brain function is active.

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 ηij 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 (η = 0. 5636 for CN, 77 =0. 555 for CT, 77 = 0. 5616 for PN, η = 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.

Objective Functional MRI (fMRI) was measured in responses to stimulations of different frequencies to investigate dominant hemisphere and tonotopic organization in primary and secondary auditory cortex. Methods 25 healthy subjects with normal hearing were examined using tones of 0. 5,2 or4 kHz that were amplitude modulated (AM) sinusoidally at 8 Hz. The AM signals were presented at 96 dB SPL Event-related design was combined with a sparse clustered volume acquisitioning paradigm for data collection in the attempt to reduce the influence of acoustic scanner noise. SPM2 software was used for offline data analyzing. Results Data from 9 subjects were discarded due to a large head movement during recording. In the rest of 16 subjects, activation was found mainly in the primary auditory cortex. In most of these cases, the activation area and intensity by BOLD were find to be decreased with increasing signal frequency. In a great portion of cases (6 left and 7 right hemispheres) , a lateral-medial preference for low-to-high frequency response shift was clearly demonstrated in the primary auditory cortex. However, this was not clear in all other cases. No significant rule could be found in secondary auditory cortex activation. Conclusion The responses to AM signals showed a clear lateralization to left cerebral hemisphere. The activated area and response intensity decreased with increasing frequency of stimulation. The activation is related to the signal frequency with high frequency AM activating more medially.

Objective To study the changes of amplitude of low-frequency fluctuation (ALFF) of the resting-fMRI in the mesial temporal lobe epilepsy (mTLE) with bilateral hippocampal sclerosis ( HS) , and discussed its underlying neuro-pathophysiological mechanism. Methods The resting-fMRI data of 20 TLE patients with HS and 20 normal volunteers were performed ALFF analysis. The amplitude of the blood oxygenation level-dependent activation of the resting-state brain was investigated. The brain structures showing increased and decreased ALFF in TLE patients were demonstrated by comparing to normal subjects with 2-sample t-test with threshold of P <0. 01. Results By comparison with that of normal subjects, the regions showing increased and decreased ALFF in TLE patients were distributed in the brain symmetrically and bilaterally. The regions showing increased ALFF were distributed with center of limbic system, such as parahippocampal gyri, araygdale, hypothalamus, dorsal anterior cingulate gyrus and part of posterior insular lobe, as well as the neocortices such as primary sensorimotor cortices, occipital cortices, inferior temporal gyri, orbital gyri, and the subcortical structures of verbal brainstem and mesial cerebellum. The point with maximal increased ALFF(T = 6. 02) located in the right precentral gyru (15, -12,51). While the regions showing decreased ALFF covered the areas of default mode, such as posterior cingulate cortex/ precuneus and medial prefrontal cortex /ventral anterior cingulate cortex, as well as other structures such as dorsal lateral prefrontal corties, superior temporal gyri, caudate heads, dorsal brain stem and the posterior cerebellum (3, -78, -21) with the maximal decreased ALFF(T= -4.42). Conclusion The method of ALFF allows the direct observation to the epileptic activation in TIE. The increased ALFF is considered the facilitation such as the epileptic activity generation and propagation; while the ALFF decrease is considered the function inhibition in these regions, especially implies the suspension in the default mode activity.

Objective To analyze and compare the Imaging findings of adult idiopathic scoliosis and degenerative scoliosis which were the most common adult scoliosis, and evaluate imaging characteristics. Method The radiological and clinical data of 98 case, among them, 41 cases of adult idiopathic scoliosis and 57 cases of degenerative scoliosis,were analyzed retrospectively. Result There were differences at presence age, sex ratio, anatomic area of scoliosis and apex between two types of adult scoliosis. The analyses and comparison between the two groups revealed significant change in the Cobb angle, involved segment and convex side orientation (all P <0. 05). Conclusion Adult idiopathic scoliosis and degenerative scoliosis show distinctive imaging characteristics. These characteristics combining clinical data are decisive in diagnosis.

Objective To investigate and elucidate how to preserve the pituitary stalk in the microsurgery of giant pituitary adenoma ( GPA) and its clinical significance. Methods 45 GPA patients, 23 males and 22 female; aged 40. 8, including 12 cases of invasive pituitary adenoma ( IPA) underwent craniotomy based on the respective preoperative neuroradiological imaging characteristics. The anatomical relationship between the pituitary stalk and tumor was recorded. The methods to protect the pituitary stalk were summarized. Results Total tumor excision was achieved in 25 patients (55. 5% ) , near-total resection was done in 12 (26.7%), and subtotal resection in 8 (17.8%). During the surgical proceeding, the pituitary stalk was distinguished from the tumor and preserved well in all 33 cases with non-invasive giant pituitary adenoma On the contrary, in the 12 cases of invasive giant pituitary adenoma (IPA) the pituitary stalk was visualized in only 7 cases. In the patients with visualized pituitary stalks 4 pituitary stalks were not identified very well. In most cases(91% )the pituitary stalks were located laterally (on the left or right side) or supero-posterior to the tumor, only a few were located anteriorly. In all 12 IPA patients 2 cases of postoperative hemorrhage occurred associated with remnant tumor and immediate hematoma evacuation was performed, however, one patient died due to hypothalamus injury. Conclusion Pituitary stalk has various anatomical relationships to the entity of GPA; most are located lateral or supero-posterior to the tumor. However, the relationship between the stalk and tumor is not clear in IPA. Identifying and preserving the pituitary stalk well during surgical manipulation will be beneficial to get an excellent outcome.

Objective To investigate the differences in etiology, symptoms, treatment, and prognosis between the patients with cerebral venous and sinus thrombosis ( CVST) before December 31 2000 and those after that date. Methods The etiology, symptom, treatment, and prognosis of the 35 CVST patients admitted to Peking Union Medical College Hospital (PUMC) from January 1 1991 to December 31 2000 (Group A, n = 16) and those admitted from January 1 2000 to May 31 2007 ( Group B, n = 19) were analyzed and compared. Results (1) The first two common causes were infection and hematological disease in Group A, while the first two common causes were immune disease and hematological disease in Group B. (2) The common symptoms and signs and positive rates were as follows; headache (86%), seizures (34% ) , focal neurological deficits (40% ) , vision deficits (43% ) , altered consciousness (31% ) , and papilloedema (60% ) without significant differences between these 2 groups. The positive rates of the common symptoms and signs during discharge were as follows: headache (77% ) , altered consciousness (73%), seizures (67%), focal neurological deficits (57%), vision deficits (43%), and altered consciousness (31%) without significant differences between these 2 groups. (3) 38% of the patients in Group A (re =6) received anticoagulation therapy, a rate significantly lower than that of Group B(79% , n = 19) (P < 0.05). Four patients in Group B received thrombolytic therapy. Conclusion The etiological constituents of CVST patients admitted in PUMC has changed, the weight of infection has declined and that of the immune disease has risen. The spectrum of signs remains unchanged; however, the rate of anticoagulation has ascended.

Objective To investigate the characteristics of clinical manifestations, diagnostic imaging, pathology, and microsurgical treatment of spinal cavernous malformation. Methods The clinical data of 28 patients with spinal cavernous malformation undergoing total resection through posterior approach during 1991 -2006, all receiving MRI examination and 22 also receiving spinal DSA examination, were analyzed. Results Among the 28 cases, 8 lesions were located in the cervical segment of the spinal cord; 12 lesions in the cervical-thoracic segment; 4 lesions in the thoracic segment; 2 in the lumbar segment, and 2 in the thoraco-lumbar segment The MRI images looked like mulberry; a black ring around the cavernoma was indicated. The spinal cord tissues around the lesion were obviously stained by the deposited hemosiderin. Follow-up of 3 months to 6 year showed no recurrence. Conclusion MRI is the most reliable method for diagnosis of spinal cavernous malformation and surgical resection is the best treatment method. The key of success is meticulous surgical techniques. DSA helps differentiate spinal cavernous malformation from other arterio-venous malformations.

Objective To investigate the effectiveness of high frequency induced thermotherapy in the treatment of hepatocellular carcinoma Methods We included a 65 proven cases of hepatocellular carcinoma in which the diagnosis was confirmed by pathology, radio-imaging and AFP value. The patients were randomly divided into 2 groupsby odd or even hospitalization number. A total of 32 patients were enrolled in the TACE + PEI only group and 33 patients were enrolled in the TACE + HITT therapy group. Results For the 32 patients in TACE + PEI only therapy group, the 1,2, and 3 year of survival rates were 73% , 56% , and 23% , respectively, with a median survival of 1. 876 years. For patients in the therapy group, the 1,2, and 3 year survival rates were 87% , 76% , and 51% , respectively, with a median survival of 2. 134 years. Survival rate and duration in the therapy group was significantly greater in the combination therapy group compared to the control group (P < 0. 05 ). There was a negative correlation between the effectiveness of combination therapy and the mortality risk ( P < 0. 05). Conclusion HiTT + TACE can significantly increase survival rate and extend length of survival in patients with hepatocelluar carcinoma.

Objective To investigate the clinico-epidemiology features of infrarenal abdominal aortic aneurysm (AAA) and relevant prognostic factors. Methods The clinical records of 375 infrarenal AAA patients, 282 males and 93 females, aged (62 15) , hospitalized 1988～2007were analyzed. Results In recent ten years, the number of patients admitted because of AAA was 186. 6% as high as that in the last 10 years The rupture rate of the male AAA patients was 14. 4% , significantly higher than that of the female AAA patients (6. 5% , P < 0. 05). The rupture rate of the AAA aged patients >65 was 3. 6% , significantly lower than that of the AAA patients <65 (17. 7% , P <0. 01). The aneurysm diameter of the patients with hyperextension was (6. 1 3. 3 ) cm, significantly lower than that of the patients without hypertension [ (6. 8±2. 3) cm. P < 0. 05 ]. The general 5-year survival rate was 70. 1 %. The 5-year survival rates of the female patients, patients ≥ 65, without hypertension, and without coronary heart disease were, all significantly higher than those of the male patients, patients < 65, and patients with hypertension or coronary heart disease (all P < 0. 05 ) . Cox regression analysis showed that sex, smoking, and hypertension were all prognostic factors (all P < 0. 05 ). Conclusion The morbidity of AAA increases fiercely. The AAA patients being male, smoking, or with hypertension have poorer prognosis, and age and operation method are not related to prognoses.

Objective To explore the patterns of neuronal activity in the basal ganglia nucleus in parkinsonian patients with levodopa-induced dyskinesia ( LID). Methods Sixteen idiopathic parkinsonian patients, 11 males and 5 female;5; aged 56. 1±11. 9, with the mean disease duration of ( 10. 1±6.6) . Years and Hoehn & Yahr score ranging 2 -4, all with the symptoms of tremor, rigidity, and bradykinesia, 8 with severe LID [with the mean unified Parkinson's disease rating scale (UPDRS) IV score of 6. 1±1. 5 underwent pallidotomy ( n = 8) or subthalamic nucleus ( STN) deep brain stimulation (DBS) implantation (6 bilaterally and 2 unilaterally). Microrecording was performed in the globus pallidus internus (Gpi) and STN. Electromyogram (EMG) on the contralateral limbs to surgery was simultaneously recorded. Single unit analysis was performed. The interspike interval (ISI) and coefficient of variation ( CV) of ISI were calculated. One-way ANOVA and rank test were employed to compare the ISI and CV among the patients. Results Two hundred and thirty-eight neurons were identified from the Gpi ( n = 8) and STN n = 14). 22. 6% of them were tremor-related neurons, 33. 8% were rapid tonic neuronal activity related, and 29. 0% were irregular neuronal activity-related. It was discovered that 8. 0% of the neurons from Gpi and STN were with grouped discharge following long period pause with the CV of 87±0. 55, and 7. 5% of the neurons were with low frequency firing with the mean frequency of (17. 7±5. 9) Hz. ANOVA revealed that in the STN the CV of the neurons with irregular with grouped discharge was significantly higher than those of the neurons with irregular neuronal activity and with low frequency firing ( both P < 0. 05 ) , the ISI of the neurons with irregular grouped discharge was .significantly higher than that of the neurons with low frequency firing and significantly higher than that of the neurons irregular neuronal activity ( both P < 0. 05); and in the Gpi the CV of the neurons with irregular grouped discharge was significantly lower than those of the neurons with irregular neuronal activity and those with low frequency firing and the ISI of the neurons with irregular grouped discharge was significantly higher than those of the other groups (all P < 0. 05 ) . Chi square test showed that majority of the neurons with grouped discharge and neurons with low frequency firing mainly existed in the Gpi and STN of the PD patients with LID (all P < 0. 05 ). Conclusion The altered neuronal activity in the basal ganglia nucleus of Gpi and STN plays an important role in the pathophysiology of PD and LID.

Objective To investigate the effects of glutamine on the changes of nuclear factor (NF) -KB and lung pathology in acute lung injury. Methods Forty SD rats underwent injection of lipopolysaccharide (LPS) 5 mg/kg into the femoral vein, and were randomly divided into 4 equal groups; Group B; undergoing injection of glutamine 0. 75 g/kg into the femoral vein Ih before LPS injection, Group C undergoing injection of glutamine and LPS simultaneously, and Group D undergoing injection of glutamine Ih after LPS injection, and Group E without glutamine injection. Another 10 rats underwent injection of normal saline to be used as controls (Group A). Four hours after the LPS injection the rats were killed with their lungs taken out. RT-PCR was used to detect the level of nuclear factor (NF)-KB mRNA expression. ELISA was used to detect the tumor necrosis factor (TNF) - in lung. The activity of superoxide dismutase (SOD) was examined by hydroxylamine method, and the malondialdehyde level was determined by thiobarbituric acid (TBA) method. Results The lung NF-KB mRNA expression levels and TNF- levels of Groups B, C, D, and E were all significantly higher than that of Group A ( all P < 0. 01). The lung NF-KB mRNA expression levels and TNF- levels of Groups C and D were all significantly lower than those of Group B (P <0. 01). However, there were no significant differences in lung NF-icB mRNA expression level and TNF- level between Group B and Group E (both P >0. 05). The SOD activity of Group B was significantly lower than that of Group A and the MDA content of Group B was significantly higher than that of Group A ( both P < 0. 05 ). The SOD activity levels of Groups C and D were significantly higher than that of Group B and the MDA content of Groups C and D were significantly lower than that of Group B ( P < 0. 01 or P < 0. 05). However there were no significant differences in lung SDD activity and MDA content between Groups B and E (both P > 0. 05 ). Obvious inflammatory changes were seen in the lungs of Groups B and E at the similar extent. Only slight infiltration could be seen in Groups C and D. The lung of Group A was normal. Conclusion Early glutamine administration protects the lung against acute LPS injury. The mechanism may be inhibition of the overexpression of NF-KB mRNA.

Objectives To investigate in vivo osteogenic potential in size-critical bone defect after percutaneous autologous grafting of culture-expanded rabbit autologous BMSCs, osteo-induced BMSCs and combination of both. Methods BMSCs were cultured and then induced with osteogenic supplement ( OS) medium. BMSCs with and without OS induction were collected and percutaneously autologously injected respectively into the 15 mm bone defect of 20 experimental rabbit model. The grafts were BMSCs, osteo-induced BMSCs, BMSCs and osteo-induced BMSCs, BMP combined with fibrin sealant, and 0.9% NaCl solution. Osteogenesis at the defect areas were observed by regular radiography, histology and biomechanics. Results the group transplanted with BMSCs + osteo-induced BMSCs aehived complete bone healing with medullary cavity united, which showed the largest quantity of new bone measured by X-ray analysis, and also their maximal load were better than those in other groups. Conclusion The bone-forming ability of rabbit osteo-induced BMSCs combined with BMSCs in bone defect is superior to those of BMSCs and osteo-induced BMSCs.

Objective To investigate the correlation between ERK1/2 cascade and c-fos after hippocampal neuron epileptiform discharge. Methods Hippocampal neurons were collected from Wistar rats and cultured in magnesium-free extra-cellular fluid to establish hippocampal neuron epileptiform discharge model. Then the hippocampal neurons were divided into 2 groups: inhibitor group, added with 10 μmol/L U0126, inhibitor of ERK 1/2 pathway, and control group without any treatment, got at 0 min). Using double-label immunofluorescence, laser scanning confocal microscopy was performed to detect the disposition of phosphorylated-ERKl/2(p-ERKl/2) and c-fos in the neurons. Western blotting was used to detect the expression of p-ERKl/2 and c-fos 0 min, 30 min, 2 h, 6 h, 12 h, and 24 h following corresponding treatment Results Double-label immunofluorescence examination displayed that there was p-ERKl/2 in both the cytoplasm and nucleus, but c-fos in the nucleus only. Western blotting manifested that p-ERKl/2 was observed at each time points in the model group, and the expression pattern of c-fos was the same as p-ERK1/2, which peaked 30 min after treatment In the inhibitor group, p-ERKl/2 was inhibited completely, and c-fos was decreased obviously. The c-fos expression levels at different time points of the inhibitor group were all significantly lower than those of the model group (all P <0. 01). Conclusion After hippocampal neuron epileptiform discharge, ERK1/2 is activated for a long time, and the expression of c-fos is down-regulated by blocking the phosphorylation of ERK1/2.

Objective To explore the effects of intervertebral disc degeneration on the biomechanical behavior of the lumbar motion segment Methods A three-dimensional nonlinear finite element model of L4-L5 segment was established using CAD technique based on CT images. A normal disc model and three degenerative disc models were established by changing the parameters such as disc material properties and disc height The effects of disc degeneration on the biomechanical properties, including stiffness, nucleus pressure, maximum von Mises stress in the annulus, and force of posterior structure were studied under two moment loads (flexion and extension) and for three different direct forces (compression, and anterior and posterior shear forces) , and the stress distribution of vertebral body and end- plate was also analyzed. Results The stiffness of the lightly degenerative disc model was decreased compared with that of the normal disc, while it was increased in the moderately and severely degenerative disc models when compared with the normal disc. The force of posterior structure in the lightly degenerative disc model was increased while the values of force of posterior structure in the moderately and severely degenerative disc models were decreased gradually. The maximum von Mises stress in the annulus increased, and the nucleus pressure decreased as the disc degeneration progressed. Moreover, the stress of intervertebral disc, vertebral body, and end-plate was distributed more peripherally. Conclusion Light degeneration of intervertebral disc leads to instability of lumbar spine, while the stability restores with further degeneration of disc. There is a negative correlation between the force of posterior structure and the load on the intervertebral disc. With the disc degeneration progressing, the intervertebral disc load pattern changes, the stress of intervertebral disc, vertebral body, and end-plate is concentrated peripherally.

Objective To evaluate the teaching effects of emergency care simulator ( ECS) combined with problem-based learning ( PBL) in teaching of cardiopulmonary resuscitation ( CPR) . Methods 42 medical students were randomly divided into 2 equal groups, control group receiving PBL and training of specific operation such as artificial respiration, external cardiac compression, tracheal intubation, and defibrillation, and ECS group receiving ECS training in addition. Then test was given to record the scores in artificial respiration. A questionnaire survey was conducted to collect the feedback. Results There were no significant differences in the scores of artificial respiration, external cardiac compression, tracheal intubation, and defibrillation between the 2 groups (all P > 0. 05 ) . There were significant differences between the Control group and the ECS group (P < 0. 05 ) The percentages of students with enhanced emergency awareness、 emergency skill, team spirit and cooperative effort, with improved analytic skill in clinical setting and in amalgamating the theoretic learning with textbook knowledge and clinical practice were all higher in the ECS group than in the control group (all P<0. 05). More than 86% of the students considered that there was significant difference between these two groups. Conclusion Using ECS combined with PBL in teaching CPR technique directly involves the medical students in " emergency practice" , resolving of " all sorts of problems" , enhancing emergency awareness, and emergency skill. It can improve teaching quality significantly that is in accordance with the development of modern medicine.

A 37-year-old male was admitted to the hospital for the fourth time on December 1, 2001 due to repeated fatigue and pain in the liver area for more than 2.5 years and aggravated for half a month.

The patient was a 17-year-old female, unmarried, who denied sexual life history. He was admitted to hospital because of "leucorrhea increased for more than 1 year, and pelvic mass was found for 4 days". The patient usually had regular menstruation, but the leucorrhea increased in the past 1 year, without abdominal distension, abdominal pain, and no obvious vulvar itching.