High-Resolution Diffusion-Weighted Imaging of C6 Glioma on a 7T BioSpec MRI Scanner: Correlation of Tumor Cellularity and Nuclear-to-Cytoplasmic Ratio with Apparent Diffusion Coefficient.

RATIONALE AND OBJECTIVES: To determine the association of the apparent diffusion coefficient (ADC) with quantitative cellularity and the nuclear-to-cytoplasmic ratio in C6 glioma. MATERIALS AND METHODS: Animal models bearing C6 gliomas underwent MR scans with T1 rapid acquisition with relaxation enhancement (RARE), T2 RARE, and high-resolution diffusion-weighted imaging sequences. For each model, three consecutive sections were used to draw regions of interest (ROIs) and measure ADC values; the middle section was localized in the plane with the maximal solid tumor area. The minimal, mean, and maximal ADC values were recorded for each ROI. GFAP-immunostained sections coregistered with ADC measurements were used to calculate tumor cellularity and the nuclear-to-cytoplasmic (N/C) ratio. Spearman's correlation was used to assess the relationship between ADC values and quantitative tumor cellularity as well as N/C ratios with a significance level of p < 0.05. RESULTS: Thirty-three sections from 11 glioma-bearing rats were analyzed. The median values of the minimal, mean, and maximal ADC were 0.443 × 10-3, 0.744 × 10-3, and 1.140 × 10-3 mm2/s, respectively. The median cellularity and N/C ratio were 2151.234 per 0.025 mm2 and 0.857, respectively. The minimal, mean, and maximal ADCs were all significantly associated with cellularity, with correlation coefficients of -0.712 (p < 0.001), -0.631 (p < 0.001), and -0.460 (p = 0.007), respectively. The minimal and mean ADC had significant negative relationships with the N/C ratio, with correlation coefficients of -0.565 (p =  0.001) and -0.426 (p = 0.013), respectively. CONCLUSION: The minimal ADC correlated well with cellularity and N/C ratios in C6 glioma and may be used as a biomarker of these two pathological features.

Diffusion kurtosis imaging differs between primary central nervous system lymphoma and high-grade glioma and is correlated with the diverse nuclear-to-cytoplasmic ratio: a histopathologic, biopsy-based study.

OBJECTIVES: To determine whether water kurtosis and diffusional metrics derived from diffusional kurtosis imaging (DKI) within primary central nervous system lymphomas (PCNSLs) and high-grade gliomas (HGGs) correlate with cellularity and/or nuclear-to-cytoplasmic (N/C) ratio. METHODS: Forty-four and 43 pathologically confirmed high-grade glioma and primary central nervous system lymphoma specimens between May 2013 and November 2016 were retrospectively reviewed. Diffusional metrics, kurtosis metrics, cellularity, and N/C ratios in PCNSLs and HGGs were compared using the Mann-Whitney U test (significant level, p < 0.007 [0.05/7]); Bonferroni correction). RESULTS: Mean kurtosis (MK), axial kurtosis (K//), and radial kurtosis (K⊥) in PCNSLs were 0.857 (0.693-0.924), 0.837 (0.660-0.941), and 0.834 (0.685-0.937), respectively; and 0.629 (0.524-0.716), 0.575 (0.511-0.689), and 0.675 (0.532-0.766), respectively, in HGGs (all p < 0.001). No significant differences in fractional anisotropy (FA), mean diffusion (MD), axial diffusion (λ//), and radial diffusion (λ⊥) were found between HGGs and PCNSLs. Cellularity was higher in PCNSLs than in HGGs (p = 0.125); whereas, the N/C ratio in PCNSLs was significantly higher than that in HGGs (p < 0.001). All DKI metrics (FA, MD, λ//, λ⊥, MK, K//, and K⊥) were significantly correlated with N/C ratio in PCNSLs with correlation coefficients being rho = 0.418, - 0.722, - 0.525, - 0.768, 0.704, 0.579, and 0.686, respectively. Cellularity in PCNSLs and HGGs did not correlate with any kurtosis or diffusional metrics. CONCLUSIONS: Difference of kurtosis parameters between PCNSLs and HGGs is correlated with their diverse N/C ratio. KEY POINTS: • DKI has considerable value in differentiating between PCNSLs and HGGs. • DKI can provide important information on nuclear-to-cytoplasmic ratio. • Difference of kurtosis parameters between PCNSLs and HGGs correlated well with their diverse N/C ratios.

Study on denervated rat skeletal muscle by 7.0 T 31P-MR phosphorus spectroscopy / 中华放射学杂志

Objective@#To investigate the changes of 31P-MRS in denervated skeletal muscle at 7.0 T MR system.@*Methods@#In the experiment group, a total of 18 male Sprague-Dawley rats aged 6-8 weeks old and weighing 200-250 g were obtained. The right posterior femoral nerve were transected, and the proximal stumps were ligated by using 5-0 nylon stitches to preclude spontaneous repair. A sham surgery (incision and exploration of the nerve) was performed at the same time (n=6). Before rat model established and at varying times after initial surgery (3 d, and 1, 2, 4, 6, and 8 weeks). 31P-MR spectra of rat quadriceps femoris were acquired on 7.0 T Agilent small animal MR imaging system. We quantified the phosphocreatine (PCr), adenosine triphosphate(β-ATP), and inorganic phosphate (Pi) using Creatine phosphate disodium salt(10 mmol/L) as an external standard. The ratios, include PCr/Pi, Pi/β-ATP, PCr/β-ATP, PCr/(PCr+Pi) and Pi/(PCr+Pi) were quantified in jMRUI. All data were analyzed by one way analysis of variance (ANOVA) with posttest inter-group comparisons using Bonferroni test. Comparative analysis methods between the experimental and control group were performed via independent samples t test. P<0.05 was considered as statistically significance.@*Results@#The average measured concentrations of β-ATP, PCr, and Pi in control groups were (6.654±0.178) μmol/g, (25.656±0.738) μmol/g, and (1.594±0.096) μmol/g, respectively. There were significant statistically differences in β-ATP, PCr, Pi, PCr/Pi, PCr/PCr+Pi,Pi/PCr+Pi between the study and control group(P<0.05) at any measurement time point after denervation. Pi/β-ATP,PCr/β-ATP and pHi in the experimental group significantly statistically differed from those of the control group (all P<0.05)at each time point except on day 3 after operation. The total concentrations of β-ATP and PCr were reduced by 11.5% and 19.7% respectively on day 3. Thereafter, β-ATP and PCr declined rapidly by 63.1% and 68.8% at week 4 respectively, then decreased slowely by 74.0%和82.3% till week 10. The change of PCr/Pi is similar to β-ATP and PCr, but more remarkable. Pi, Pi/PCr+Pi, Pi/ATP showed a progressively increase till week 10. The intra-cellular pH (pHi) of normal rat muscles was 7.033±0.017, While the pHi gently in experiment rat muscles decreased during the entire experiment.@*Conclusion@#31P-MRS with 7.0 T can quantify the temporal changes of energy metabolism and pHi in normal and denervated rat muscles. It shows that the dysfunction of energy metabolism are progressive with time and that they begin within a short period following the nerve section, the change of β-ATP, PCr, PCr/Pi take place primarily within 4 weeks after denervation. β-ATP, PCr, and PCr/Pi may be potential biomarkers of energy metabolism in the evaluation of denervated muscle atrophy.

Perfusion imaging of brain gliomas using arterial spin labeling: correlation with histopathological vascular density in MRI-guided biopsies.

INTRODUCTION: This study was designed to determine if cerebral blood flow (CBF) derived from arterial spin labeling (ASL) perfusion imaging could be used to quantitatively evaluate the microvascular density (MVD) of brain gliomas on a "point-to-point" basis by matching CBF areas and surgical biopsy sites as accurate as possible. METHODS: The study enrolled 47 patients with treatment-naive brain gliomas who underwent preoperative ASL, 3D T1-weighted imaging with gadolinium contrast enhancement (3D T1C+), and T2 fluid acquisition of inversion recovery (T2FLAIR) sequences before stereotactic surgery. We histologically quantified MVD from CD34-stained sections of stereotactic biopsies and co-registered biopsy locations with localized CBF measurements. The correlation between CBF and MVD was determined using Spearman's correlation coefficient. P ≤ .05 was considered statistically significant. RESULTS: Of the 47 patients enrolled in the study, 6 were excluded from the analysis because of brain shift or poor co-registration and localization of the biopsy site during surgery. Finally, 84 biopsies from 41 subjects were included in the analysis. CBF showed a statistically significant positive correlation with MVD (ρ = 0.567; P = .029). CONCLUSION: ASL can be a useful noninvasive perfusion MR method for quantitative evaluation of the MVD of brain gliomas.

Safety and short-term efficacy of MR guided focused ultrasound surgery for bone metastasis-induced pain palliation / 中华放射学杂志

Objective To discuss the safety and short-term efficacy of MR-guided focused ultrasound surgery (MRgFUS) for pain palliation of bone metastases patients.Methods Fourteen patients with painful bone metastases were recruited in this prospective study.The treating efficacy was characterized by numerical rating scale (NRS),the brief pain inventory quality of life (BPI-QOL) survey,and Karnosky performance status scale (KPS).Adverse events occurred pre-and post-treatment were analyzed.Normal distributed statistics was analyzed by using paired-samples t test or Wilcoxon rank sum test.Results Fourteen patients were treated with MRgFUS,2 patients dropped out of the study.The NRS ratings are 6.50(4.00),5.00 (5.25),2.50(5.00),2.50(4.75),2.00 (6.00) for pre-treatment,one week,one month,two months,and three months,respectively.Such variances of NRS ratings were statistically significant (Z=-2.773,-2.740,-2.769,-2.675;P＜0.05).The BPI-QOL ratings were (42.42± 8.27),(30.67 ± 12.29),(29.17±15.38),(29.92± 17.67) and (35.67± 19.28),respectively.The BPI-QOL ratings decreased in the first two months after the treatment which is statistically significant (t=3.231,2.820 and 2.453;P＜0.05);whereas for the third month,the BPI-QOL rating was statistically insignificant compared with the one before the treatment (P＞0.05).The KPS ratings were 80(28),80(20),65(45) for pre-treatment,one week and three months after treatment,respectively.Three months after the treatment,the KPS ratings decreased which was statistically significant compared with the one before the treatment (Z=-2.204,P＜0.05).After the treatment,one patient developed deep venous thrombosis,three patients reported lower extremities numbness,two patients had soft tissue edema around the lesions.Conclusions MRgFUS is effective for short-term pain palliation of bone metastases.Such noninvasive technique is safe and can improve patients' living condition.

Non-Gaussian diffusion MR imaging of glioma: comparisons of multiple diffusion parameters and correlation with histologic grade and MIB-1 (Ki-67 labeling) index.

INTRODUCTION: This study was conducted to compare the association of Gaussian and non-Gaussian magnetic resonance imaging (MRI)-derived parameters with histologic grade and MIB-1 (Ki-67 labeling) index (MI) in brain glioma. METHODS: Sixty-five patients with pathologically confirmed glioma, who underwent diffusion-weighted MRI with 2 b values (0, 1000 s/mm(2)) and 22 b values (≤5000 s/mm(2)), respectively, were divided into three groups of grade II (n = 35), grade III (n = 8), and grade IV (n = 22). Comparisons by two groups were made for apparent diffusion coefficient (ADC), slow diffusion coefficient (Dslow), distributed diffusion coefficient (DDC), and heterogeneity index α. Analyses of receiver operating characteristic (ROC) curve were performed to maximize the area under the curve (AUC) for differentiating grade III + IV (high-grade glioma, HGG) from grade II (low-grade glioma, LGG) and grade IV (glioblastoma multiforme, GBM) from grade II + III (other grade glioma, OGG). Correlations with MI were analyzed for the MRI parameters. RESULTS: On tumor regions, the values of ADC, Dslow, DDC, and α were significantly higher in grade II [(1.37 ± 0.29, 0.70 ± 0.11, 1.39 ± 0.34) (×10(-3) mm(2)/s) and 0.88 ± 0.05, respectively] than in grade III [(0.99 ± 0.13, 0.55 ± 0.07, 1.04 ± 0.20) (×10(-3) mm(2)/s) and 0.80 ± 0.03, respectively] and grade IV [(1.03 ± 0.14, 0.50 ± 0.05, 1.02 ± 0.16) (×10(-3) mm(2)/s) and 0.76 ± 0.04, respectively] (all P < 0.001). The parameter α showed the highest AUCs of 0.950 and 0.922 in discriminating HGG from LGG and GBM from OGG, respectively. Significant correlations with histologic grade and MI were observed for the MRI parameters. CONCLUSION: The non-Gaussian MRI-derived parameters α and Dslow are superior to ADC in glioma grading, which are comparable with ADC as reliable biomarkers in noninvasively predicting the proliferation level of glioma malignancy.

Comparison of contrast-enhanced SPACE and CISS in evaluating cavernous sinus invasion by pituitary macroadenomas on 3-T magnetic resonance.

PURPOSE: SPACE (sampling perfection with application-optimized contrasts by using different flip angle evolutions) and CISS (constructive interference in steady state) are 3-dimensional sequences that can increase the signal intensity of cavernous sinus. The purpose of this study was to determine whether contrast-enhanced (CE) SPACE and CE CISS can well demonstrate cavernous sinus invasion (CSI) by pituitary macroadenoma and which one performed better. METHODS: In 56 cavernous sinuses from 28 patients with pituitary macroadenoma, CSI grades and image quality were assessed by using CE SPACE and CISS. The assessment results were compared with Knops' classification on T1-weighted images. The interreader agreement of assessment results were analyzed with k statistics. Qualitative analyses were compared using the Wilcoxon signed-ranks test. RESULTS: Two radiologists were in substantial agreement of CSI evaluation on both CE SPACE (k = 0.87) and CE CISS (k = 0.83). The evaluation results on CE SPACE (k = 0.76) were more coincident with Knops' classification than CE CISS (k = 0.71). Identification of CSI worked well with either CE SPACE or CE CISS, but CE SPACE performed better (mean, 3.48 ± 0.61 vs 3.28 ± 0.80; P < 0.05). Contrast-enhanced SPACE had significantly higher image scores than CE CISS in description of the relationship between pituitary adenoma and internal carotid artery (mean, 3.26 ± 0.93 vs 2.96 ± 1.01; P < 0.05). Contrast-enhanced CISS demonstrated more susceptibility artifacts (10.7% vs 0%; P < 0.05) and vessel flow artifacts (53.6% vs 0%; P < 0.05). There was no significant difference regarding contrast enhancement of pituitary adenoma and cavernous sinus (mean, 3.07 ± 1.12 vs 3.04 ± 0.96; P > 0.05). CONCLUSIONS: Contrast-enhanced SPACE is superior than CE CISS for identification of CSI by pituitary macroadenoma.

Application of MR angiography and perfusion weighted imaging in the evaluation of abnormal vessels in Moyamoya disease, cerebral revascularization after operation and cerebral hemodynamics during the perioperative period / 中华放射学杂志

Objective To evaluate the clinical value of MRA on the abnormal vessels in Moyamoya and cerebral revascularization , and to evaluate PWI in the observation of cerebral hemodynamics before and after cerebral revascularization.Methods Twenty-four patients with Moyamoya disease ascertained by DSA received cerebral revascularization on one side.MRA and PWI were performed for all patients before and after the operation , while DSA was performed after operation in nine patients to compare the images of MRA and DSA by three experienced radiologists.Perfusion parameters in terminal branches of middle cerebral artery ( MCA) on the operative side were compared with those on the contralateral sides and the cerebellum , including cerebral blood flow (CBF), cerebral blood volume (CBV), mean transit time (MTT), and delay time ( DT) , as well as relative ratio ( values on the operative side/values on the contralateral side , and values on the operative side/values on the cerebellar region ) of perfusion parameters (rCBF, rCBV, rMTT and rDT) were calculated.Comparisons of the data between different groups were performed using paired Student′s t test.Results MRA was similar to DSA in displaying the internal carotid artery , main branches stenosis, Moyamoya vessels, and cerebral revascularization.DSA was better in displaying collateral vessels than MRA, but primary images of MRA provided anatomic and pathologic information of cerebral parenchyma.After the operations , rCBF (1.30 ±0.27) and rCBV (1.26 ±0.21) of MCA perfusion regions on the operative and the contralateral sides were higher than rCBF (0.73 ±0.15) and rCBV (0.98 ±0.12) before the operation significantly (t=-7.19,-6.64,P<0.05).rMTT (1.06 ±0.20) and rDT (1.07 ± 0.18) after the operation were lower than rMTT(1.53 ±0.34)and rDT (1.40 ±0.26) before the operation (t=5.62,5.40,P<0.05) .In MCA perfusion regions on the operative and cerebellar sides , rCBF(1.93 ± 0.34)and rCBV(2.25 ±0.35)were higher than rCBF(0.88 ±0.18)and rCBV(1.16 ±0.22)(t=-3.04,-3.06,P<0.05) before the operation.rMTT (1.13 ±0.29) and rDT (1.29 ±0.12) were lower than rMTT (1.88 ±0.19 ) and rDT ( 3.29 ±0.47 ) before the operation ( t =4.01, 4.72, P <0.05 ).Conclusions MRA is a safe , reliable method to evaluate abnormal vessels and cerebral revascularization after the operation in moyamoya disease.PWI can detect poor cerebral perfusion , and can be used for assessment of the effect of cerebral revascularization.

Changes in the reproductive endocrine function in rat following intraovary microinjection of inhba overexpression lentivirus vectors.

OBJECTIVE: To investigate the reproductive endocrine changes after inhba overexpression into rat ovary. METHOD: Thirty Sprague-Dawley rats were randomly assigned to three groups. Inhba overexpression lentivirus vectors (LV-eGFP-inhba) were microinjected into rat ovary (INH group); Control animals received the same amount lentivirus vector empty (CON group) or LV-eGFP (GFP group). Antral follicle amount and diameter were counted and serum level of activin A, E2, P, FSH, and LH and the expression of ER-α, ER-ß, PR, FSHR, and LHR were measured. RESULTS: There was no significant difference among three groups in antral follicle amount; antral follicle diameter was increased in INH group rats compared with the other group rats. Serum levels of activin A, E2, P, and FSH were increased and LH was decreased in INH group rats compared with the other group rats. The mRNA and protein expression of ER-α, ER-ß, FSHR was higher in INH group rats than that in the other group rats. There was no significant difference in mRNA and protein expression of PR among the three group rats, LHR expression was decreased in INH group rats compared with the other two group rats. CONCLUSION: inhba overexpression in rat ovary in vivo may change reproductive endocrine function.

TEMPORARY REMOVAL: MRI and 1H-MRS on diagnosis of pineal region tumors.

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MR features of mice spleen lymphocytes labeled with super-paramagnetic iron oxide particles / 中华放射学杂志

Objective To investigate the feasibility of labeling mice spleen lymphocytes with superparamagnetic iron oxide(SPIO)and in vitro MR imaging of the labeled cells.Methods Spleen lymphocytes of 5 mice were isolated and then labeled with SPIO of 100,50,25,15,10,5 μg/ml,which was previously prepared with PLL.Prussian blue staining was performed to show the intracellular iron.Cell viability was compared among fresh,labeled and unlabeled cells.Different concentrations of mice spleen lymphocytes were screened using 3.0 T MR on T2WI,T2 * WI and SWI sequences in vitro.Cell viability was compared using independent-sample t test between groups.The MRI values among different groups were compared using one-way ANOVA.Results SPIO prepared with PLL could successfully label mice spleen lymphocytes,the optimum concentration of SPIO was 5 μg/ml.The Prussian blue staining showed intracellular blue spots and a labeling efficiency of(93.6 ± 2.1)％.Three groups of fresh,labeled and unlabeled cells showed a Trypan blue staining result of(94.8 ± 3.1)％,(88.7 ± 2.7)％,and(88.9 ±3.2)％,respectively; no statistically significant difference was found in cell viability between labeled and unlabeled lymphocytes(t =0.281,P ＞ 0.05); however,the cell viability of fresh cells were statistically significant higher than the labeled and unlabeled lymphocytes(t =8.125 and 7.253 respectively,P ＜0.05for all).Among the T2 WI,T2 * WI and SWI sequences under the same concentrations of cells,the SWI sequence was the most sensitive.Conclusions The mice spleen lymphocytes can be effectively labeled with SPIO with no impact on cell viability,and MR can be used to track these labeled cells in vitro.The SWI sequence is the most sensitive.

Transient ischemic attack and stroke can be differentiated by analyzing the diffusion tensor imaging.

OBJECTIVE: We wanted to differentiate between transient ischemic attack (TIA) and minor stroke using fractional anisotropy and three-dimensional (3D) fiber tractography. MATERIALS AND METHODS: The clinical data, conventional magnetic resonance imaging (MRI), diffusion weighted imaging (DWI) and diffusion tensor imaging (DTI) were obtained for 45 TIA patients and 33 minor stroke patients. The fractional anisotrophy ratio (rFA) between the lesion and the mirrored corresponding contralateral normal tissue was calculated and analyzed. The spatial relationship between the lesion and the corticospinal tract (CST) was analyzed and the lesion sizes in the minor stroke patients and TIA patients were compared. RESULTS: Twenty-two of the 45 TIA patients (49%) revealed focal abnormalities following DWI. The rFA was significantly lower (p < 0.05) in the stroke patients (0.71 ± 0.29) compared to that of the TIA patients (1.05 ± 0.37). The CST was involved in almost all stroke lesions, but it was not involved in 68% of the TIA lesions. The TIA patients had significantly lower CST injury scores (3.25 ± 1.75) than did the stroke patients (8.80 ± 2.39) (p = 0.004). CONCLUSION: Our data indicate that TIA and minor stroke can be identified by analyzing the rFA and the degree of CST involvement, and this may also allow more accurate prediction of a patient's long-term recovery or disability.

Study on p38 mitogen activated protein kinase in vascular endothelial cells dysfunction in preeclampsia / 中华妇产科杂志

Objective To study expression and activation of p38 mitogen activated protein kinase (MAPK) in vascular endothelial cells dysfunction in preeclampsia. Methods From Sept. 2009 to Mar.2010, 54 pregnant women underwent deliveries in the First Affiliated Hospital of Chongqing Medical University were enrolled in this study, including 20 patients in mild preeclampsia group, 16 patients in severe preeclampsia group and 18 women with term cesarean section without perinatal complications as control group. Placental endothelial cells were labeled by CD34 to assay microvessel density (MVD) of each group. Immunohistochemical SP and western blot were used to detect localization and expression of p-p38 MAPK protein, respectively. The levels of sera soluble fms-like tyrosine kinase-1 (sFlt-1)and soluble endoglin(sEng) were measured by ELISA. Results ①The MVD of placenta were 103 ± 3 in control group, 81 ±5 in mild preeclampsia group and 63±4 in severe group, respectively, which showed statistical difference among each group (P＜0.05).②The expression of p38 MAPK protein were 0.84±0.05 in control group,0.90±0.14 in mild group and 0. 86 ±0.18 in severe group, which did not reach remarkable difference among each group (P＞0.05). The expression of p-p38 MAPK protein were 0.13±0.05 in control group,0.59±0.12 in mild group and 1.16±0.18 in severe group, which show statistical difference among each group(P＜0.05).(3) The localization of p-p38 was in trophoblast, endothelial cells and a few (5.2±0.3)and(10.9±0.4)μg/L in control group,(12.5±1.2) and (20.4±5.3)μg/L in mild group and (19.3±3.0) and (29. 5 ±3.7) μg/L in severe group. When drawing paired comparison in those p-p38 MAPK protein levels and the concentrations of serum sFlt-1, sEng in preeclampsia groups (r=0.68,P＜0.05;r=0.87,P＜0.05). Conclusions The remarkable activation of the p38 MAPK in the placenta of patients with preeclampsia induced the increased levels of sFlt-1 and sEng in maternal serum, which confer the injury of vascular endothelial cells that caused the significant decline of MVD in placentas. p38 MAPK signaling might be one of the key pathways in vascular endothelial cell dysfunction in preeclampsia.

1H-MR spectroscopy changes in transient ischemic attack patients and their correlation with perfusion-weighted imaging.

PURPOSE: We investigated whether patients with transient ischemic attack (TIA) have metabolic changes in the brain. METHODS: 35 patients with clinically diagnosed TIA were prospectively included in our study. Clinical and neurological data were compiled. 1H-MR spectroscopy and perfusion-weighted imaging were performed in all patients within 3 days of the onset of symptoms. RESULTS: In TIA patients, the N-acetylaspartate (NAA)/choline (Cho) ratio in noninfarcted regions was significantly decreased in the symptomatic hemisphere (1.33 +/- 0.38) compared with the asymptomatic hemisphere (1.51 +/- 0.41, p < .05). Patients with a history of prior TIA had a significantly decreased NAA/Cho ratio in both the symptomatic (p < .05) and asymptomatic (p < .05) hemispheres compared with TIA patients without a prior TIA. TIA patients with diffusion-weighted imaging lesions had a significantly increased lactate/NAA ratio in both the symptomatic (p < .05) and asymptomatic (p < .05) hemispheres compared with TIA patients without lesions. The relative cerebral blood flow (rCBF) value was directly related to the symptomatic Cho/creatine (Cr) value (r = 0.81, p < .01). The higher the rCBF value, the higher the symptomatic Cho/Cr value. CONCLUSIONS: TIA patients have neurological deficits that are transient; however, metabolic damage to the brain is present up to 3 days after the onset of the symptoms. These metabolic changes are not restricted to the symptomatic hemisphere or to areas close to ischemic lesions and the changes are related in the CBF.

CT and MR Imaging Features of Dysembryoplastic Neuroepithelial Tumor / 实用放射学杂志

Objective To analyze CT and MR imaging features of dysembryoplastic neuroepithelial tumor(DNT),so that to improve its diagnostic accuracy.Methods CT and MRI fidnings of DNT in 10 cases proved surgically and pathologically were retrospectively reviewed.Results All lesions were located in the super-tentorial gray matter regions or involved the cererbral certex mainly.The lesions were round,lobular,triangular or irregular pseudocystic masses with definite borders mostly.The lesions were hypointense on T_1WI and hyperintense on T_2WI.On fluid attenuated inversion recovery weighted images,the hyperintense "ring sign" and septa of the lesions were seen.On diffuse-weighted images(DWI),the lesions were hypointense or slight hypointense.On MR spectroscopy,NAA of the lesions slightly decreased.There were no peripheral edema and mass effect with well-demarcated.7 lesions had no enhancement and 3 lesions had slight unhomogeneous enhancement after administration of contrast medium.The lesions in 2 cases on plain CT showed low attenuation and one had calcification inside the lesion.Conclusion DNTs are of typical neuroradiologic features,that may be helpful for the diagnosis of which preoperatively.

Clinical diagnosis of 5 cases of pituitary stalk interruption syndrome / 中华内分泌代谢杂志

Objective To raise the level of clinical diagnosis for the patients with pituitary stalk interruption syndrome (PSIS). Methods Five patients (4 males) with PSIS were retrospectively analyzed with respects to the clinical features, endocrine status and image characteristics. Magnetic resonance imaging (MRI) scan was performed at hypothalamic-pituitary region. Results The clinical manifestations of all patients consisted of growth retardation and delayed puberty without polyuria. Deficiency of multiple anterior pituitary hormones was revealed in all patients by the evaluation of endocrine status. The features of MRI included a lack of visible pituitary stalk, absence of posterior lobe hypersignal in the sella turcica and a hyperintense spot in the region of the thalamus opticus. Conclusion The clinical characteristics of patients with PSIS are growth retardation and delayed puberty. The evaluation of anterior pituitary function is necessary. The detection of an anatomical abnormality around hypothalamic-pituitary region by MRI is important diagnostic evidence.

Study of relationship of an androgen receptor CAG repeat polymorphism with postmenopausal osteoporosis / 中华老年医学杂志

Objective To study the relationship between a CAG repeat polymorphism of the androgen receptor (AR) gene and postmenopausal osteoporosis (PMO). Methods Genotypes for the AR polymorphisrn were determined by gene scan and DNA sequence methods in a case-control study,including 78 cases of PMO at femoral neck and 73 cases as controls, and 108 cases of PMO at lumbar spine (L2-4) and 60 cases as controls. Bone mineral density for the proximal femur and L2-4 was measured by NORLAND XR-46 dual-energy X-ray absorptiometry. The relationship between the CAG repeat polymorphism and PMO was investigated. Results Eleven different allelic variants,containing 18, 20, 21, 23, 24, 25, 26, 27, 28, 29, and 30 CAG repeats were detected, 16 genotypes were present in the subjects. There were no significant differences in the genotype and allele distributions of (CAG) n polymorphism between PMO group (SS : 25.6 %, SL : 39.7%, LL : 34.6 % ;S:45.5%,L:54.5%) and control group (SS: 23.3%,SL=45.2% ,LL:31.5%;S:45.9%,L:54.1%) at the femoral neck site (all P＞0.05). The risk of PMO at femoral neck in females with the genotypes of SL (0R:0.798,95%CI:0.335～1.797), the LL (0R:0.998,95%CI:0.425～2.341), and the combined SL and LL (OR:0.880, 95% CI: 0.419～1.852) were not significantly increased in comparison with those of females with the SS genotype (all P＞0.05). There were no significant differences in the genotype and allele distributions of (CAG)n polymorphism between PMO group(SS: 18.5%, SL: 49.1%, LL: 32.4%;S:43.1%, L: 56.9%) and control group (SS: 21.7%, SL:45.0% ,LL:33.3% ;S:44.2% ,L:55.8%) at the L2-4 site (P＞0. 05). The risk of PMO at L2-4 in females with the genotypes of SL (OR:1. 276,95%CI:0. 552～2. 950), the LL (OR:1. 137,95%CI:0.468～2.766), and the combined SL and LL (OR: 1. 217,95% CI: 0. 556 ～2. 663 ) were not significantly increased in comparison with those of females with the SS genotype (all P＞0.05). After adjustments for age, postmenopausal period, menopausal age, and body mass index, the logistic regression analyses revealed the (CAG)n polymorphism was not significantly associated with PMO at the femoral neck and L2-4 site (all P＞0.05). Conclusions The CAG repeat polymorphism in the AR gene may not be associated with PMO at the femoral neck and L2-4 site.

Change of heart rate power spectrum and its association with sudden death in the fetuses of rats with intrahepatic cholestasis of pregnancy / 生物医学工程学杂志

<p><b>UNLABELLED</b>To investigate the relationship between imbalance of cardiac autonomic nervous system and sudden death in fetuses of rats with intrahepatic cholestasis of pregnancy (ICP), the animal model of ICP was induced by hypodermic injection of 17-alpha-ethinylestradiol and progesterone. The electrocardiograms and frequency domain analysis of heart rate variability (HRV) including low frequency (LF), high frequency (HF) and the ratio between low and high frequencies (LF/HF) of fetal rats by the 21st day of gestation were evaluated with Chart 5 software of Powerlab biologic signal extracting and analyzing system.</p><p><b>RESULTS</b>(1) The serum total bile acids (TBA) levels of pregnant rats were (78.5 +/- 4.5) micromol/L in Group ICP and (24.6 +/- 3.6) micromol/L in Group control; significant difference was noted between the two groups (P < 0.01). (2) In Group ICP, fetal rats arrhythmias appeared after (29.3 +/- 6.4) minutes' observation, and fetal rats died suddenly after (23.5 +/- 4.6) minutes' arrhythmias; However, the fetal rats in Group control all showed normal electrocardiograms over 90 minutes' continuous observation. (3) The values of LF and LF/HF of fetal rats in Group ICP within 20 minutes before fetal rats arrhythmias were significantly higher than those in Group control (LF 48.45 +/- 4.11 nu vs. 33.87 +/- 4.31 nu, and LF/HF 0.99 +/- 0.14 vs. 0.61 +/- 0.10, respectively, P < 0.01). (4) Dynamic power spectral analysis of HRV indicated that the values of LF and LF/HF of fetal rats in Group ICP increased progressively within 15 minutes before the sudden death of fetal rats. These demonstrated that autonomic imbalance in association with increased sympathetic activity has been strongly implicated in the pathophysiology of fetal arrhythmogenesis and sudden death in ICP. HRV analysis could be a useful tool for fetal surveillance, especially for ICP.</p>

Chaotic analysis on cardiac systems of normal pregnant rats and fetuses / 生物医学工程学杂志

<p><b>UNLABELLED</b>This investigation was made to explore the chaotic characteristics of cardiac system and differences of autonomic nervous system development of normal pregnant rats and fetuses. The electrocardiograms, chaotic graphics and digital characteristics of heart period signal (HPS) of normal pregnant rats and fetuses by day 21st were evaluated with a computerized HPS extracting and analyzing system.</p><p><b>RESULTS</b>(1) The mean values of frequency and voltage of fetal rats electrocardiograms were lower than those of pregnant rats significantly (P < 0.01). (2) Being similar to those in human, the chaotic graphics showed three-amplitudes spectral features in both normal pregnant rats and fetuses. However, the second amplitude and third amplitude were lower in fetal rats than in pregnant rats. (3) The Heart Relative Dispersion, Lyapunov Exponent and Fractional Dimension were significantly lower in fetal rats than in pregnant rats (P < 0.01). These findings demonstrated that the autonomic nervous system development of fetal rat was still immature and it exhibited lower complexity of HPS and chaotic degree than that of pregnant rat did.</p>