Association of iron metabolism with cognitive function in elderly patients with type 2 diabetes mellitus / 中华内分泌代谢杂志

Objective To investigate the association of iron overload with metabolic changes in hippocampal tissues, and to explore the relationship between iron metabolism abnormality and cognitive function in elderly patients with type 2 diabetes mellitus( T2DM) . Methods A total of 97 elderly inpatients with T2DM were enrolled. According to the Mini-mental state examination ( MMSE) score, the type 2 diabetic patients were divided into mild cognitive impairment ( MCI) and non-mild cognitive impairment ( Non-MCI) groups. A retrospective analysis was performed for their clinical data and laboratory parameters, including serum ferritin, MMSE, Montreal cognitive assessment ( MoCA) , carotid intima-media thickness, ankle brachial index, and the ELISA method was used to detect soluble transferring receptor ( sTfR ) . Proton MR spectroscopy ( 1 H-MRS ) was performed in the hippocampus of 26 patients. Results Compared with Non-MCI group, MCI group revealed higher age(P<0.01), higher incidence of carotid plaque (P<0.01), decreased sTfR(P=0.049) and left hippocampal height(P=0.034). Age, sTfR, and carotid plaque were independent risk factors for MCI in elderly patients with T2DM. Conclusion The abnormal iron metabolism may contribute to the occurrence of MCI in the elderly patients with T2DM.

Utility of in vitro proton magnetic resonance spectroscopy in aetiological characterisation of brain abscesses.

Purpose: Brain abscesses often present an aetiological dilemma. Microscopy is insensitive and culture techniques are time consuming. Hence, a new rapid technique in vitro Proton Magnetic Resonance Spectroscopy ( 1 HMRS) was evaluated for its usefulness in the identification of aetiology of brain abscesses. Materials and Methods: A total of 39 pus specimens from brain abscesses were subjected to in vitro 1 HMRS. These pus specimens were also processed by conventional culture methods. The spectral patterns generated by in vitro 1 HMRS were further correlated with culture results. Results: Pus specimens which showed the presence of anaerobes on culture revealed the presence of multiplet at 0.9 ppm (100%), lactate-lipid at 1.3 ppm (100%), acetate at 1.92 ppm (100%) and succinate at 2.4 ppm (75%). Pus specimens that revealed the presence of facultative anaerobes on culture showed a pattern B, i.e., the presence of lactate-lipid at 1.3 ppm (100%), acetate at 1.92 ppm (88.88%) along with the multiplet at 0.9 ppm (100%). Pattern C was seen in aerobic infection which showed the presence of lactate-lipid at 1.3 ppm (100%) along with the multiplet at 0.9 ppm. Pus from two tuberculous abscesses showed the complete absence of multiplet at 0.9 ppm. Conclusions: We observed in this study that it was possible to differentiate bacterial and tuberculous brain abscesses using in vitro 1 HMRS. Further, it was also possible to distinguish between aerobic and anaerobic brain abscesses on the basis of spectral patterns. In vitro 1 HMRS of fungal and actinomycotic brain abscess are also presented for its unusual spectra.

Real-Time fMRI-Guided Functional MR Spectroscopy: The Lactate Peaks at the Motor Cortex during Hand-Grasping Tasks

PURPOSE: There is debate concerning the observation of metabolite changes on MRS at the designated cortex during some tasks. The purpose of this study is to assess the change of the lactate content at the motor cortex during hand-grasping tasks with performing real-time fMRI-guided fMRS. MATERIALS AND METHODS: Seven healthy volunteers (23-28 years old) underwent realtime fMRI during right hand grasping tasks with using a 1.5 T system. After confirming the activating area, single voxel MRS was preformed at 1) the baseline, 2) during the task and 3) after the task on the activating cortex. The three consecutive spectra were compared for observing the changes of the lactate content by the tasks. The Cho/Cr, NAA/Cr and Lac/Cr ratios were calculated manually from those spectra. RESULTS: MRS during the tasks revealed the lactate peaks at the 1.33 ppm resonance frequency with great conspicuity at the activated area, which was identified on the real-time fMRI. After the task scan, the lactate peaks completely disappeared and the spectra recovered to the values of the baseline scan in all volunteers. At baseline, during the task and after the task, the Cho/Cr ratios were 0.81, 0.76 and 0.77, respectively, and the NAA/Cr ratios were 1.68, 1.65 and 1.72, respectively, and the Lac/Cr ratios were 0.28, 0.41 and 0.30, respectively. During the task, Lac was significantly increased by 46%. CONCLUSION: We observed prominent lactate peaks on MRS during hand-grasping tasks at the activated area, as was shown on the real-time fMRI. We suggest that fMRS can be used as a sensitive tool for observing the metabolite changes of the functioning brain.

MR Spectroscopy Evaluation and Short-term Outcome of Olfactory Ensheathing Cells Transplantation in Amyotrophic Lateral Sclerosis Patients / 中国修复重建外科杂志

Objective To evaluate proton MR spectroscopy (1H-MRS) for detection of the motor cortex and adjacent brain in amyotrophic lateral sclerosis (ALS) patients with apparent upper motor neuron involvement after olfactory ensheathing cells(OECs) transplantation. Methods From December 2004 to February 2005, 7 patients with clinically definite ALS who could safely undergo MRS were admitted into the perspective study. The neurological status, ALS functional rating scale (ALSFRS), EMG, and 1H-MRS taken before and 2 weeks after operations were carefully analyzed. The NAA/Cr and Cho/Cr ratios were measured in the cerebral peduncle, genu and posterior limb of the internal capsule, corona radiata and precentral gyrus. Results The ALSFRS in 2 cases improved obviously whose ALSFRS increased from 30 to 33 and from 29 to 34 respectively. And 5 cases remained stable 2 weeks after OECs transplantation. Statistical analyses for all seven cases showed both the NAA/Cr and Cho/Cr ratios decreased, but in the two cases with ALSFRS improvement the NAA/Cr increased in the certain anatomic position which confirmed the neurological and EMG findings. Conclusion The proton MR spectroscopy is a suitable noninvasive measure for ALS evaluation. The preliminary study suggests that two of the seven ALS cases improved apparently short-term after OECs transplantation. More patients are required for the clinical study and longer follow-up duration is needed for future research.

Evaluation of the Antenatal Fetal Brain Metabolites using Proton Magnetic Resonance Spectroscopy / 대한주산의학회잡지

OBJECTIVE:The purpose of this study was to compare the sensitivity of proton Magnetic Resonance Spectrography (MRS) for estimating absolute metabolite concentrations and ratio of fetal brains. METHODS:Between September 2005 and August 2006, our study was prospective single center trial and included 39 healthy women (Group 1: fetuses with risk factor of fetal distress or hypoxic damage [n=15], Group 2: fetal CNS anomalies on ultrasound [n=12], Group 3: normal fetuses [n=12]). We quantified resonances for the main proton MRS-detectable brain and calculated metabolite ratios of the three groups. We compared the obtained metabolite levels of the three groups with electronic fetal cardiotocography, Doppler ultrasound examination, Apgar score, and umbilical artery blood gas analysis. RESULTS:Abnormal amniotic fluid, abnormal Doppler studies, and abnormal cardiotocograms were significantly more prevalent in Group 1 compared with those of Group 2 and 3. In Group 1, choline (Cho) levels (7.86+/-3.51mmol/L) were significantly higher than in Group 2 or 3 (p=0.024). The ratios of N-acetylasparate (NAA)/creatinine-phosphocreatine (Cr) and Cho/Cr were increased whereas the ratios of NAA/Cho, lactate (Lac)/Cho, Lac/NAA, and Lac/Cr were decreased; however, there was no statistical significance. In patients who have oligohydramnios and absence of umbilical diastolic flow, choline and N-acetylasparate levels were significantly elevated (p<0.05, p<0.05, respectively). But, MRS metabolites and ratios showed no significant differences for low Apgar scores, umbilical arterial academia, uterine artery notching, maternal blood pressure or abnormal fetal cardiotocograms. CONCLUSION:This study demonstrates the possibility of performing proton MRS to assess the metabolic information of the fetal brain. Further technical progress may be useful of improving the degree of detection of hypoxic changes or an impending hypoxic state for prenatal diagnosis.

The Study of ~1 HMRS in Diagnosis of Astrocytoma / 实用放射学杂志

Objective To assess the value of ~1 HMRS in the classification and differential diagnosis of astrocytoma. Methods 58 cases of astrocytoma including 18 cases of diffuse astrocytoma, 24 cases of anaplastic astrocytoma and 16 cases of glioblastoma were all examined by routine MR scan and ~1 HMRS, statistical analysis was done on Cho/Cr, Cho/NAA and NAA/Cr ratio. Results Diffuse astrocytoma showed slightly elevated Cho, a bit decreased NAA and Cr. Lac wave did not appear. Anaplastic astrocytoma and glioblastoma both manifested distinctly elevated Cho, obviously decreased NAA and Cr. Lac wave existed in 6 cases. In diffuse astrocytoma the ratio of Cho/NAA was 2.72?1.16, Cho/Cr was 2.66?1.21, NAA/Cr was 1.02?0.34. In anaplastic astrocytoma the ratio of Cho/NAA was 5.69?1.32, Cho/Cr was 4.92?1.46, NAA/Cr was 0.92?0.16. In glioblastoma the value of Cho/NAA was 5.71?1.08, Cho/Cr was 5.12?1.76, NAA/Cr was 0.87?0.13.Conclusion It is very significant of ~1 HMRS in the classification and differential diagnosis of astrocytoma.

The Study of Brain Proton Magnetic Resonance Spectroscopy and the Volume of the Hippocampus in Mild Cognitive Impairment and Mild Alzheimer Disease / 实用放射学杂志

Objective To evaluate the roles of proton magnetic resonance spectroscopy(1H-MRS) and the volume of the hippocampus(HCV) measured by MRI in the diagnosis and the differential diagnosis of mild cognitive impairment (MCI) and mild Alzheimer disease (AD).Methods HCV and 1H-MRS were performed in the bilateral hippocampus and the bilateral medial temporal lobes(MTLS) in 30 cases with MCI,30 cases mild with AD and 30 healthy persons in age and sex-matched with controls by using volume analysis software and stimulates echo acquisition mode(STEAM). The ratios of NAA/Cr,Cho/Cr,MI/Cr,NAA/MI and HCV were compared among these groups.The contributions of HCV and 1H-MRS in diagnosis of MCI and AD was compared.Correlation coefficients were calculated for Mini Mental State Examination (MMSE) scores and HCV or the ratios of NAA/Cr,Cho/Cr,MI/Cr and NAA/MI in the MCI group and the mild AD group.Results Patients with mild AD showed significant reduction of HCV and NAA/Cr and NAA/MI ratios in the bilateral HCVand MTLS,and significant MI/Cr increase in the bilateral MTLS relative to control subjects. Patients with MCI demonstrates significant reduction of NAA/Cr in the left MTL , significant reduction of the bilateral HCV and NAA/MI ratio and significant MI/Cr increase in the bilateral HCV and MTLS relative to control subjects. Patients with mild AD showed statistical differences of MI/Cr and NAA/MI ratios in the left MTL relative to patients with MCI . Patients with mild AD showed no significant differences of HCV and NAA/Cr relative to patients with MCI .The Cho/Cr ratios among three groups showed no significant differences. HCV yielded the volume with the sensitivity 50% and specificity 83.33% in the diagnosis of MCI . 1H-MRS yielded the ratios with 43.33% in sensitivity and 81.25% in specificity in the di- agnosis of MCI.The combination of HCV and 1H-MRS yielded the volume and ratios with sensitivity of 73.33% and specificity of 84.62% in the diagnosis of MCI. HCV yielded the volume with sensitivity of 73.33% and specificity of 88% in the diagnosis of mild AD.1H-MRS yielded the ratios with sensitivity of 70% and specificity of 87.5% in the diagnosis of mild AD.The combination of HCV and 1H-MRS yielded the volume and ratios with sensitivity of 83.33% and specificity of 86.21% in the diagnosis of mild AD. HCV yielded the volume with the sensitivity of 50% and specificity of 62.5% in the differential diagnosis of MCI and mild AD.1H-MRS yielded the ratios with sensitivity of 56.67% and specificity of 65.38% in the differential diagnosis of MCI and mild AD.The combination of HCV and 1H-MRS yielded the volume and ratios with sensitivity of 66.67% and specificity of 64.52% in the differential diagnosis of MCI and mild AD. Patients with mild AD and MCI showed significant correlation between MMSE and the bilateral HCV ,NAA/Cr ratio. Patients with mild AD showed significant correlation between MMSE and right NAA/MI ratio .Patients with mild AD and MCI showed significant correlation between HCV and NAA/Cr ratio. Conclusion The combination of HCV and 1H-MRS are the best choice in the diagnosis and the differential diagnosis of MCI and mild AD.

In Vivo Proton MR Spectroscopic Change of Experimental Rat Brain Abscess Model

OBJECTIVE: This study was designed to clarify the phasic changes and distinctive spectral features of the brain abscess in the in vivo proton MR spectroscopy during the processes of abscess formation in rats, in relation to MR images. METHODS: Staphylococcus aureus was stereotactically inoculated into the predetermined location of the right frontal brain of SPF controlled Sprague-Dawley female rats(200-250gm). T1 weighted image(WI), T2WI and gadolinium enhanced image(CEMR) were obtained serially prior to each MR spectroscopy in order to visualize the infected lesions. RESULT: Three characteristic peaks, from proton MR spectroscopy, were found. A dominant peak was shown at 1.3ppm, which was due to the high concentration of mobile lipid or lactate, and smaller two peaks were shown at 0.8-1.0ppm and 1.9ppm, due to the small concentration of aminoacid(leucine, isoleucine. valine) and acetate, respectively. The lactate peak has increased during the stage of cerebritis and started to decrease in its early capsulation stage, finally invisible in its late capsulation stage(p=0.0001). The change of lactate peak was conspicuous at the early stage of cerebritis while the change of MR image was rather subtle. The aminoacids peak remained small throughout all stages. The acetate peak was shown in the late stage of cerebritis. However, it's peak area of integration was not exactly measured because of overlapping on the N-acetylaspartate peak. On the other hand, the peak of N-acetylaspartate and creatines, which could be observed in normal brain, remained at low level after sharp decrease in the early stage of cerebritis(p=0.004, p=0.005). The cholines peak decreased in the early stage of cerebritis, but it was not statistically significant(p=0.124). CONCLUSION: From this study, we were able to observe the characteristic MR spectroscopic features of each stage even from such a small volume of abnormal lesions with a 2X2X3mm 3 voxel size. Furthermore, based on our results that inflammatory change could be detected earlier by MR spectroscopy than by MR images, MR spectroscopy may be applied for early diagnosis of the brain abscess.

: 1H-MR spectroscopic and SPECT findings in a patient with MELAS syndrome confirmed by molecular genetic analysis

An eighteen-year-old girl presented recurrent partial and generalized seizures associated with the T-2 high signal intensities of MR brain imaging. Serum and CSF lactate levels were elevated. Muscle biopsy revealed "ragged red fiber" . The diagnosis of MELAS was confirmed by molecular genetic analysis showing 3,243 mtDNA point mutation. Localized proton MR spectroscopy was performed on a GE 1.5 T SIGNA MRI/MRS system and analyzed by STEAM (Stimulated Echo Acquisition Method). 1H-MR spectrocopy demonstrated elevation of lactate contents and decrease of N-acetyl aspartate contents in the involed area. The Tc99m-ECD SPECT revealed multifocal decrease of perfusion in bilateral parietal, temporal and occipital lobe, especially right temporal and left occipital lobe. These features suggest that the pathology of brain lesions of MELAS syndrome may be sub-necrotic incomplete ischemic changes caused by metabolic derangement.