-
[show abstract]
[hide abstract]
ABSTRACT: To evaluate the values of ocular hemodynamics and serum endothelin-1 (ET-1) in the early diagnosis of diabetic retinopathy (DRP).
A total of 85 DRP patients were examined by ophthalmoscope and fluorescein angiography and divided into 3 groups: no obvious retinopathy (n = 20), non-proliferative diabetic retinopathy (n = 35) and proliferative diabetic retinopathy (n = 30). Control group included 15 healthy volumterrs. The peak systolic velocity (PSV), end diastolic velocity (EDV) and resistance index (RI) of ophthalmic artery (OA) and central retinal artery (CRA) were measured by color Doppler energy imaging. The level of endothelin-1 was measured by radioimmunoassay. Then plasma ET-1 levels and eye vascular hemodynamic parameters were compared with correlation and diagnostic specificity after data analysis.
Compared with the control group, DRP, EDV and PSV decreased progressively while RI increased gradually (P < 0.05). EDV and RI were more sensitive than PSV in diagnosis. The plasma level of ET-1was significantly higher than that of control group (P < 0.05). And it was correlated positively with RI and negatively with PSV and EDV of CRA. The diagnostic value of EDV was higher than that of ET-1 level.
Ocular hemodynamics become abnormal during the early stage of DRP and worsen with the progress of DRP. An elevated plasma level of ET-1 may lead to the abnormity of retinal hemodynamics. The test of plasma ET-1 and the examination of ocular hemodynamics may play an important role in the early diagnosis of DRP.
Zhonghua yi xue za zhi 01/2013; 93(1):37-40.
-
[show abstract]
[hide abstract]
ABSTRACT: To clarify pathological basis of computed tomography (CT) presentations of colorectal cancer (CRC) with schistosomiasis for the purpose of improving the accuracy of CT diagnosis and differential diagnosis of the condition.
130 patients (87 male and 43 female; age range 49-86 years, mean 71.1) were selected whose diagnoses were pathologically confirmed as CRC with schistosomiasis. All the patients underwent abdominal plain CT and contrast enhanced scanning. The location, morphology, size, calcification features and enhancement modalities (patterns) were evaluated and compared with the pathological findings by two radiologists in a blind way.
CT showed that in 130 patients, the tumors occurred in the large intestine, among which 109 (83.9%) were solitary and 21 (16.1%) were multifocal. The intestinal wall was irregularly thickened in 123 patients, with soft tissue masses in 7 patients. Linear, spotty and small patchy calcifications were seen in 104 (80.0%) patients, with unclear margins in 96 patients. The tumors were markedly unevenly enhanced in 92 patients. Pathological examination revealed adenocarcinoma in 114 patients and in 104 patients, calcified Shistosoma japonicum (S. japonicum) ova inside the tumors, 15 patients were mucinous adenocarcinoma, and one patient was that of adenosquamous carcinoma.
Irregular thickening of the intestinal wall, soft tissue masses, multiple S. japonicum ova calcifications inside the tumor with obscured margins and multiple intestinal masses in some patients are important CT features of CRC with schistosomiasis.
European journal of radiology 06/2012; 81(8):e835-43. · 2.65 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: To construct the functional networks of human brains by resting-state functional magnetic resonance imaging (fMRI) and examine whether or not the small-world property of functional brain networks changes in patients with Alzheimer disease (AD).
A total of 33 AD patients and 20 healthy old volunteers were recruited. Their cognitive functions were evaluated by the mini-mental state examination (MMSE) and Mattis dementia rating scale (DRS). The resting-state BOLD-fMRI data were acquired and preprocessed. Then the correlation coefficient of every pair of 90 regions was calculated and correlation matrix Z (N×N, N = 90) generated by Fisher Z transformation. The small-world property of functional brain networks was tested for AD patients and normal elders according to the definition of small-worldness. The changes of relevant parameters in AD patients were examined by two sample t-tests.
Behavioral results: the MMSE scores of AD group and normal controls (NOR) were 20.60 ± 2.30 and 28.20 ± 1.80 respectively. The DRS scores of AD and NOR groups were 96.00 ± 10.82 and 123.22 ± 13.74 respectively. The MMSE and DRS scores were statistically different between two groups. Calculation of small-world parameters: Within the range of 0.1 ≤ Sparsity ≤ 0.4, both groups satisfied the small-world property. However, the clustering coefficient Cp and the average shortest path Lp of AD group were significantly higher than those of NOR group at each threshold (P < 0.05).
The functional brain networks in AD patients still have the property of small-world. But the levels of Cp and Lp are higher in AD patients than those in normal controls. It suggests that the capacity of information transmission in functional brain networks and the ability of information integration in different brain regions in AD patients are impaired. This finding is of great importance in elucidating the pathological mechanisms of AD from the viewpoint of networks.
Zhonghua yi xue za zhi 03/2012; 92(9):579-82.
-
[show abstract]
[hide abstract]
ABSTRACT: Previous studies have shown that the functional brain activity in the resting state is impaired in Alzheimer's disease (AD) patients. However, most studies focused on the relationship between different brain areas, rather than the amplitude or strength of the regional brain activity. The purpose of this study was to explore the functional brain changes in AD patients by measuring the amplitude of the blood oxygenation level dependent (BOLD) functional MRI (fMRI) signals.
Twenty mild AD patients and twenty healthy elderly subjects participated in the fMRI scan. The amplitude of low frequency fluctuation (ALFF) was calculated using REST software.
Compared with the healthy elderly subjects, the mild AD patients showed decreased ALFF in the right posterior cingulate cortex, right ventral medial prefrontal cortex, and in the bilateral dorsal medial prefrontal cortex. No brain region with increased ALFF was found in the AD group compared with the control group.
The reduced activity in the posterior cingulate cortex and medial prefrontal cortex observed in the present study suggest that the functional abnormalities of those areas are at an early stage of AD. The ALFF analysis may provide a useful tool in fMRI study of AD.
Chinese medical journal 03/2012; 125(5):858-62. · 0.86 Impact Factor
-
Zhonghua yi xue za zhi 04/2011; 91(13):865-6.
-
[show abstract]
[hide abstract]
ABSTRACT: To explore the central mechanism of acupuncture in protecting gastric mucous membrane by a composite analysis of gastric mucous membrane related indices in peripheral blood and functional MRI (fMRI) signal changes after electric-acupuncturing Zusanli (ST36) acupoint.
Sixteen healthy adult volunteers were divided into true acupoint group (A) and sham acupoint group (B). Zusanli acupoint was used for Group A. Peripheral blood was drawn 5 min before and 5, 15, 25, 30 min after needle-removal for the detection of gastric mucous membrane related indices. fMRI was performed during acupuncture and the acquired fMRI data were analyzed by SPM2 (P < 0.001).
The levels of calcitonin gene related peptide (CGRP) and prostaglandin E2 (PGE2) increased while those of endothelin (ET) and gastrin (GAS) decreased significantly after acupuncture in Group A (P < 0.01). And there was no significant change in Group B (P > 0.05). Acupuncturing Zusanli activated the bilateral middle frontal gyrus, caudate, left precentral and postcentral gyri, hypothalamus, anterior cingulate cortex, right hippocampus, insula and cerebellar hemisphere. But acupuncturing the sham acupoint only activated the paracentral lobule and cerebellar hemisphere.
Acupuncturing Zusanli acupoint activates certain cortex areas and multiple systems to stimulate the release of neurotransmitters and regulate the peripheral humoral factors to achieve the protection of gastric mucous membrane.
Zhonghua yi xue za zhi 06/2010; 90(21):1458-62.
-
[show abstract]
[hide abstract]
ABSTRACT: To evaluate the effects of mesenchymal stem cell (MSC) transplantation on the growth of liver cancer.
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.
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).
MSC transplantation increases the expression of VEGF and PCNA, while decreases the expression of nm23 gene in cancer cells, thus favoring the tumor growth.
Zhonghua yi xue za zhi 03/2009; 89(7):491-6.
-
[show abstract]
[hide abstract]
ABSTRACT: 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.
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).
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.
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.
Zhonghua yi xue za zhi 07/2008; 88(23):1603-6.
-
Jing Zhang,
Pei-Jun Wang,
Xiao-Dong Yuan,
Cheng-Wei Shao, Xiao-Hu Zhao,
Wei-Guo Xu,
Ning-Xin Dong,
Guo-Liang Wang,
Zhi-Hong Shao,
Zong-Liang Huang,
Wei Zhang
[show abstract]
[hide abstract]
ABSTRACT: To evaluate the diagnostic value of CT in pancreas intraductal papillary mucinous neoplasm (IPMN) by analyzing its CT feature and pathological findings.
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.
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).
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.
Zhonghua yi xue za zhi 05/2008; 88(14):943-7.
-
[show abstract]
[hide abstract]
ABSTRACT: Anxiety disorder, a common mental disorder in our clinical practice, is characterized by unprovoked anxiety. Medial prefrontal cortex (MPFC) and posterior cingulate cortex (PCC), which closely involved in emotional processing, are critical regions in the default mode network. We used functional magnetic resonance imaging (fMRI) to investigate whether default mode network activity is altered in patients with anxiety disorder. Ten anxiety patients and 10 healthy controls underwent fMRI while listening to emotionally neutral words alternating with rest (Experiment 1) and threat-related words alternating with emotionally neutral words (Experiment 2). In Experiment 1, regions of deactivation were observed in patients and controls. In Experiment 2, regions of deactivation were observed only in patients. The observed deactivation patterns in the two experiments, which included MPFC, PCC, and inferior parietal cortex, were similar and consistent with the default model network. Less deactivation in MPFC and greater deactivation in PCC were observed for patients group comparing to controls in Experiment 1. Our observations suggest that the default model network is altered in anxiety patients and dysfunction in MPFC and PCC may play an important role in anxiety psychopathology.
European Journal of Radiology 09/2007; 63(3):373-8. · 2.61 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: To explore whether the hypertension patients with no clinical cognitive impairment manifestations have certain brain dysfunctions.
Twenty-five moderately to severely hypertensive patients, males and females, aged 63.0 +/- 1.6 (60 approximately 65), with a disease history if 5 to 10 years, and 25 sex, age, and educational level-matched healthy persons underwent tests by mini-mental status examination (MMSE) scales, state anxiety inventory (STAI-S) and trait anxiety inventory (STAI-T), and then underwent two functional magnetic resonance imaging (fMRI) studies. In Experiment 1, the subjects were demanded to listen actively to the meaningless words (pseudowords) and in Experiment 2 the subjects listened actively to real words and make the valence (abstract or concrete) of the words in silence. The subjects were told to listen passively the noise from the MR scanners during the resting period, which was used as the control task. The fMRI data were analyzed with statistical parametric mapping (SPM99) software.
The MMSE score of the patient group was 29.3 +/- 1.1, not significantly different from that of the control group (29.6 +/- 0.5, P > 0.05). The STAI-S score of the patient group was 47 +/- 5.3748, significantly higher than that of the control group (41.6 +/- 4.9777, P < 0.05). The STAI-S score of the patient group was 45 +/- 3, not significantly different from that of the control group (43 +/- 4, t = 1.0619, P = 0.3032). In Experiment 1, the activated patterns and deactivated patterns were nearly similar for the patient and control groups. The activated regions included the bilateral superior temporal lobe, bilateral inferior frontal cortex and supplementary motor areas. In Experiment 2, the activated patterns were also nearly similar for these 2 groups. The regions included the bilateral superior temporal lobe, bilateral inferior frontal cortex, left angular gyrus, bilateral superior frontal cortex, bilateral cerebellum, premotor areas, and supplementary motor areas. The deactivation patterns were similar for the patients and controls both in Experiment 1 and Experiment 2. These regions were medial prefrontal cortex, posterior cingulate and bilateral inferior parietal cortex, which nearly overlapping with the default model network proposed by Raichle et al. However, the activation and deactivation magnitude and extent of the brain were significantly greater for the patients than for the controls both in Experiment 1 and Experiment 2.
Some brain dysfunction may have already existed in patients with moderately to severely hypertension disorders, though their behavior performance scores are within the normal range of ages. The fMRI technique can be a useful tool to detect the preclinical brain abnormalities.
Zhonghua yi xue za zhi 01/2007; 87(3):170-3.
-
[show abstract]
[hide abstract]
ABSTRACT: The purpose of our study was to evaluate the correlation between the enhancement parameters of dynamic CT; the carcinoma tissue microvessel density (MVD, a hotspot method to provide a histologic assessment of tumor vascularity); and tumor nuclear grade in renal cell carcinomas.
Twenty-four patients with histologically diagnosed renal cell carcinoma underwent dynamic enhanced CT. Enhancement parameters, slope of the time-density curve, the density difference before and after tissue enhancement (deltaH), tissue blood ratio (TBR), and area under the time-density curve (AR), were calculated for all lesions. Pathology slides corresponding to the CT plane were stained using mouse antihuman CD34 monoclonal antibody and H and E. Fuhrman nuclear grade was used. Vascular hot spots of microvessels were recorded. Spearman's rank correlation was performed to determine the strength of the relationship between enhancement parameters, MVD determinations, and tumor nuclear grade.
MVD with CD34 staining revealed uneven distribution of positively stained vascular endothelial cells in renal cell carcinoma lesions. Heterogeneous distribution of contrast enhancement was seen among and within individual tumors. The tumors appeared as uneven patterns on time-density curves of renal cell carcinoma lesions. Enhancement parameters of H (median, 21.0 H; range, 2.2-105.8 H), TBR (median, 39%; range, 10.7-154.7%), AR (median, 1.58 H x sec; range, 0.23-3.67 H x sec), and slope (median, 2.76; range, 0.53-6.76) varied greatly. Renal cell carcinoma tissue MVD significantly correlated with all enhancement parameters of dynamic CT. The correlation coefficients (r) were 0.62, 0.54, 0.55, and 0.44, respectively, for delta H, slope, TBR, and AR (p < 0.0 5). All enhancement parameters did not significantly correlate with tumor nuclear grade. They were not predictive of nuclear grade.
Enhancement parameters of dynamic CT may be suited to evaluate tumor vascularity in vivo. Dynamic enhanced CT images may reflect the heterogeneity of tumor angiogenesis on the basis of the correlation between enhancement parameters and MVD of renal cell carcinoma.
American Journal of Roentgenology 05/2006; 186(5):1423-30. · 2.78 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: To explore the potential mechanism of generalized anxiety disorders (GAD).
Ten GAD patients and 10 sex- and age-matched healthy persons underwent functional magnetic resonance imaging (fMRI) study in 2 stages by block design: auditory presentation of the stimulation task. In experiment 1 emotionally neutral words were given and then alternated with a no word period for 8 cycles. In experiment 2 emotionally neutral words and threat-related words were given alternately for 8 cycles. The subjects were asked to listen carefully and then judge their subjective feeling in mind. By the end of experiment they were asked to fill in a state anxiety inventory (STAI-S) so as to calculate the STAI-S scores.
The mean STI-S score of the patients in the experiment 1 was 57 +/- 5, significantly higher than that of the healthy persons (37 +/- 3, P < 0.01); and the mean STAI-S score in the experiment 2 of the patients was 66 +/- 6, significantly higher than that of the healthy persons (41 +/- 4, P < 0.01). The fMRI findings showed that in the experiment 1 the activated cerebral regions of the 2 groups were mostly overlapped, including bilateral superior temporal gyri (BA22/42) and middle temporal gyri (BA21), premotor areas (B46), and supplementary motor areas (BA6), and cerebellar hemisphere, and left inferior prefrontal gyrus (BA44/45). However, the activation intensity levels (mean T values) of the bilateral superior temporal gyri of the patients were both significantly higher than those of the control (for the left side: P = 0.051, and for the right side: P = 0.035). In addition, activation of the dorsal lateral prefrontal cortex (BA8/9) and bilateral inferior parietal lobules (BA39/40). In the experiment 2 activation of brain areas could be seen only in the patients, including bilateral superior temporal gyri, middle temporal gyri, inferior prefrontal gyri, inferior parietal lobules, anterior motor areas, supplemental motor areas, and anterior cingulate gyri (BA8/24/32), and left dorsal lateral prefrontal cortex. No significantly activated brain area could be shown in the control at the same stringent statistic level (P < 0.01, uncorrected); however, when the threshold value (P value) was reduced to 0.01, the left anterior cingulate gyrus (BA24/32), posterior cingulate gyrus (BA29/30), and inferior parietal lobules (BA40) were all significantly activated.
Dysfunction of superior temporal lobe and dorsal prefrontal cortex, characterized by hyperactivity in response to outer stimuli, may play an important role in the psychopathologic mechanism of GAD.
Zhonghua yi xue za zhi 04/2006; 86(14):955-60.
-
[show abstract]
[hide abstract]
ABSTRACT: Kapton, a commonly used spacecraft material, is studied to investigate the atomic oxygen (AO) erosion effects in a plasma-type ground-based AO effects simulation facility. The samples before and after the experiments are compared in aspect, mass and surface morphology. The reaction characteristics of the material in the facility are obtained. The contribution of AO and ionic oxygen to mass loss in the sample and the reaction mechanism between the different particles and samples are analysed. It is concluded that neutral AO is the major cause of material erosion and mass loss and that the collision of energetic ions may accelerate the oxidation reaction.
Journal of Physics D Applied Physics 07/2001; 34(15):2308. · 2.54 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: Spacecraft traveling in low earth orbit (LEO) will react with environmental factors, such as atomic oxygen (AO), ultraviolet radiation (UV) and vacuum ultraviolet radiation (VUV), which may severely affect the lifetime of the spacecraft. Teflon, including PTFE (polytetrafluoroethylene) Teflon and FEP Teflon, is a commonly used spacecraft material. Existing studies showed that Teflon could be eroded by AO in LEO but with a lower erosion yield than most of other spacecraft materials. However, its erosion yield increases in long-term flight experiments, which might be caused by synergism of several environmental effects. In this work, experiments were conducted to investigate the erosion effects of atomic oxygen on PTFE Teflon in a ground-based simulation facility. The samples, before and after the experiments, were compared in appearance, mass, surface morphology, optical properties and surface composition. We also analysed the influence of temperature, ultraviolet radiation and vacuum ultraviolet radiation on the atomic oxygen effects. Four conclusions can be drawn: first, PTFE Teflon is eroded severely in the ground-based facility, where the erosion yield is higher than that in the flight experiments and identical to those from other ground-based facilities. Secondly, the erosion yield increases with the sample temperature. Thirdly, ultraviolet radiation has little effect on the mass loss and erosion yield of the Teflon sample in the AO experiment. Lastly, there may be some synergistic effects of atomic oxygen and vacuum ultraviolet radiation, which could be one of the main factors that cause the more severe erosion of Teflon.
Polymer Degradation and Stability.
