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Vascular mild cognitive impairment (VMCI) is an early and reversible stage of dementia. Volume differences in regional gray matter may reveal the development and prognosis of VMCI. This study selected 2 of the most common types of VMCI, namely, periventricular white matter hyperintensities (PWMH, n = 14) and strategic single infarctions (SSI, n = 10), and used the voxel-based morphometry method to quantify their morphological characteristics. Meanwhile, age- and sex-matched healthy volunteers were included (n = 16). All the participants were neuropsychologically tested to characterize their cognitive function and underwent whole-brain magnetic resonance imaging scanning. Our results showed that the volumes of the bilateral temporal lobes and bilateral frontal gray matter were obviously diminished in the PWMH group. The atrophy volume difference was 4,086 voxels in the left temporal lobe, 4,154 voxels in the right temporal lobe, 1,718 voxels in the left frontal lobe, and 1,141 voxels in the right frontal lobe (P ≤ 0.001). Moreover, the characteristics of the gray matter atrophy associated with the PWMH were more similar to those associated with Alzheimer’s disease than SSI, which further revealed the susceptibility for escalation from PWMH to dementia. In conclusion, PWMH patients and SSI patients have different morphological characteristics, which explain the different prognoses of VMCI.

This study aimed to analyse cerebral grey matter changes in mild cognitive impairment (MCI) using voxel-based morphometry and to diagnose early Alzheimer's disease using deep learning methods based on convolutional neural networks (CNNs) evaluating these changes. Participants (111 MCI, 73 normal cognition) underwent 3-T structural magnetic resonance imaging. The obtained images were assessed using voxel-based morphometry, including extraction of cerebral grey matter, analyses of statistical differences, and correlation analyses between cerebral grey matter and clinical cognitive scores in MCI. The CNN-based deep learning method was used to extract features of cerebral grey matter images. Compared to subjects with normal cognition, participants with MCI had grey matter atrophy mainly in the entorhinal cortex, frontal cortex, and bilateral frontotemporal lobes (p < 0.0001). This atrophy was significantly correlated with the decline in cognitive scores (p < 0.01). The accuracy, sensitivity, and specificity of the CNN model for identifying participants with MCI were 80.9%, 88.9%, and 75%, respectively. The area under the curve of the model was 0.891. These findings demonstrate that research based on brain morphology can provide an effective way for the clinical, non-invasive, objective evaluation and identification of early Alzheimer's disease.

Stroke is the second leading cause of death globally and the most common cause of severe disability. Several barriers need to be addressed more effectively to treat stroke, including efficient delivery of therapeutic agents, rapid release at the infarct site, precise imaging of the infarct site, and drug distribution monitoring. The present study aimed to develop a bio-responsive theranostic nanoplatform with signal-amplifying capability to deliver rapamycin (RAPA) to ischemic brain tissues and visually monitor drug distribution. A pH-sensitive theranostic RAPA-loaded nanoparticle system was designed since ischemic tissues have a low-pH microenvironment compared with normal tissues. The nanoparticles demonstrated good stability and biocompatibility and could efficiently load rapamycin, followed by its rapid release in acidic environments, thereby improving therapeutic accuracy. The nano-drug-delivery system also exhibited acid-enhanced magnetic resonance imaging (MRI) and near-infrared fluorescence (NIRF) imaging signal properties, enabling accurate multimodal imaging with minimal background noise, thus improving drug tracing and diagnostic accuracy. Finally, in vivo experiments confirmed that the nanoparticles preferentially aggregated in the ischemic hemisphere and exerted a neuroprotective effect in rats with transient middle cerebral artery occlusion (tMCAO). These pH-sensitive multifunctional theranostic nanoparticles could serve as a potential nanoplatform for drug tracing as well as the treatment and even diagnosis of acute ischemic stroke. Moreover, they could be a universal solution to achieve accurate in vivo imaging and treatment of other diseases.

Background Sepsis-associated encephalopathy is a severe complication due to systemic infection. Although early stages involve pathophysiological changes, detection using conventional imaging is challenging. Glutamate chemical exchange saturation transfer and diffusion kurtosis imaging can noninvasively investigate cellular and molecular events in the early stage of the disease by MRI. N-acetylcysteine, an antioxidant and precursor of glutathione, regulates the metabolism of the neurotransmitter glutamate and participates in neuroinflammation. We aimed to investigate the protective role of n-acetylcysteine in sepsis-associated encephalopathy using a rat model and monitor changes in the brain using magnetic resonance molecular imaging. Methods Bacterial lipopolysaccharide was injected intraperitoneally into the rats to induce a sepsis-associated encephalopathy model. The behavioural performance was assessed using the open field test. Tumour necrosis factor alpha and glutathione levels were detected biochemically. Imaging was performed using a 7.0-T MRI scanner. Protein expressions and cellular damage were assessed by western blotting and pathological staining, respectively. We also evaluated changes in the blood-brain barrier permeability by the Evans blue staining. Results The lipopolysaccharide-induced rats showed reduced anxiety and depression after treatment with n-acetylcysteine. Magnetic resonance molecular imaging can identify pathological processes at different stages of the disease. Furthermore, rats treated with n-acetylcysteine showed increased glutathione levels and decreased tumour necrosis factor alpha, suggesting enhanced antioxidant capacity and inhibition of inflammatory processes, respectively. Western blot analysis showed a reduced expression of nuclear factor kappa B (p50) protein after treatment, suggesting that n-acetylcysteine inhibits inflammation via this signalling pathway. Finally, n-acetylcysteine treated rats also showed reduced cellular damage by pathology and reduced extravasation of their blood-brain barrier by Evan Blue staining. Conclusion This study showed that n-acetylcysteine might be a therapeutic option for sepsis-associated encephalopathy and other neuroinflammatory diseases. Furthermore, non-invasive ‘dynamic visual monitoring’ of the physiological and pathological changes related to sepsis-associated encephalopathy was achieved for the first time using magnetic resonance molecular imaging, which provides a more sensitive imaging basis for early clinical diagnosis, identification, and prognosis.

The reliable and dynamic detection of amyloid β-protein (Aβ) deposition using imaging technology is necessary for preclinical Alzheimer's disease (AD), which may significantly improve prognosis. The present study aimed to evaluate the feasibility of applying angiopep-2 (ANG), a chemical exchange saturation transfer-magnetic resonance imaging (CEST-MRI) biomarker, for monitoring Aβ deposition in vivo. ANG exerted a good chemical exchange saturation transfer (CEST) effect and displayed a moderate binding affinity to Aβ1-42 in vitro. Six-month-old mice with AD injected with ANG exhibited a significantly enhanced CEST effect than controls in vivo; this effect gradually became more apparent at 8, 10, and 12 months. Spatial learning impairment caused by abundant Aβ deposition (representing mild cognitive impairment in AD patients) develops at 12 months in APPswe/PSEN1dE9 (line 85) AD mice. To conclude, the CEST of ANG could display very earlier age-related Aβ pathological progress in mice with AD, consistent with immunohistochemistry. ANG has extraordinary potential for clinical transformation as an imaging biomarker to diagnose early AD and track its progress dynamically and nonradiationally.

Sleep deprivation leads to hippocampal injury. Proteostasis disturbance is an important mechanism linking sleep deprivation and hippocampal injury. However, identifying noninvasive imaging biomarkers for hippocampal proteostasis disturbance remains challenging. Amide proton transfer-weighted (APTw) imaging is a chemical exchange saturation transfer technique based on the amide protons in proteins and peptides. We aimed to explore the ability of APTw imaging in detecting sleep deprivation-induced hippocampal proteostasis disturbance and its biological significance, as well as its biological basis. In vitro, the feasibility of APTw imaging in detecting changes of the protein state was evaluated, demonstrating that APTw imaging can detect alterations in the protein concentration, conformation, and aggregation state. In vivo, the hippocampal APTw signal declined with increased sleep deprivation time and was significantly lower in sleep-deprived rats than that in normal rats. This signal was positively correlated with the number of surviving neurons counted in Nissl staining and negatively correlated with the expression of glucose-regulated protein 78 evaluated in immunohistochemistry. Differentially expressed proteins in proteostasis network pathways were identified in the hippocampi of normal rats and sleep-deprived rats via mass spectrometry proteomics analysis, providing the biological basis for the change of the hippocampal APTw signal in sleep-deprived rats. These findings demonstrate that APTw imaging can detect hippocampal proteostasis disturbance induced by sleep deprivation and reflect the extent of neuronal injury and endoplasmic reticulum stress.

Early life stress (ELS) is associated with an increased risk of developing depression and anxiety disorders. Disturbances of the neurobiological glutamatergic system are implicated in depression; however, the long-term effects of ELS on glutamate (Glu) metabolites remain unclear. Our study used 7T proton magnetic resonance spectroscopy (7T 1H MRS) to detect metabolic Glu in a rat model to investigate maternal deprivation (MD)-induced ELS. MD was established in Sprague-Dawley rats by periodic separation from mothers and peers. Changes in the hippocampal volume and Glu metabolism were detected by 7T 1H MRS after testing for depression-like behavior via open field, sucrose preference, and Morris water maze tests. Adult MD offspring exhibited depression-like behavior. Compared to the control, the MD group exhibited reduced ratio of central activity time to total time and decreased sucrose consumption (p < 0.05). MD rats spent less time in the fourth quadrant, where the platform was originally placed, in the Morris water maze test. According to 7T 1H MRS, hippocampus of MD rats had elevated Glu and glutamate + glutamine (Glu+Gln) levels compared with the control group hippocampi, but Gln, γ-aminobutyric acid (GABA), and glutamate + glutamine (Glu+Gln) in the prefrontal cortex of MD rats showed a downward trend. Depression-like behavior and cognition deficits related to ELS may induce region-specific changes in Glu metabolism in the prefrontal cortex and hippocampus. The novel, noninvasive 7T 1H MRS-identified associations between Glu levels and ELS may guide future clinical studies.

Intracranial atherosclerotic stenosis of a major intracranial artery is the common cause of ischemic stroke. We evaluate the feasibility of using deep learning to automatically detect intracranial arterial steno-occlusive lesions from time-of-flight magnetic resonance angiography.In a retrospective study, magnetic resonance images with radiological reports of intracranial arterial stenosis and occlusion were extracted. The images were randomly divided into a training set and a test set. The manual annotation of lesions with a bounding box labeled "moderate stenosis," "severe stenosis," "occlusion," and "absence of signal" was considered as ground truth. A deep learning algorithm based on you only look once version 5 (YOLOv5) detection model was developed with the training set, and its sensitivity and positive predictive values to detect lesions were evaluated in the test set.A dataset of 200 examinations consisted of a total of 411 lesions-242 moderate stenoses, 84 severe stenoses, 70 occlusions, and 15 absence of signal. The magnetic resonance images contained 291 lesions in the training set and 120 lesions in the test set. The sensitivity and positive predictive values were 64.2 and 83.7%, respectively. The detection sensitivity in relation to the location was greatest in the internal carotid artery (86.2%).Applying deep learning algorithms in the automated detection of intracranial arterial steno-occlusive lesions from time-of-flight magnetic resonance angiography is feasible and has great potential.

PurposeTo observe and analyze the clinical and multi-mode imaging features of eyes with PHOMS, and to introduce two cases of PHOMS which underwent multi-mode imaging.MethodsRetrospective clinical observational study. A total of 26 patients (37 eyes) with hyperreflective structures surrounded by hyporeflective edges around the optic discs who were examined and diagnosed at Shandong Eye Hospital between January 2019 and June 2021 were included in the study. Among these patients, 12 were male and 14 were female. Fifteen were monocular. The average age was 39 years. All patients underwent the following examinations: Best-corrected visual acuity (BCVA), intraocular pressure examinations, slit-lamp anterior segment examinations, indirect ophthalmoscopy, visual field examinations, fundus color photography, fundus autofluorescence (FAF), optical coherence tomography (OCT), and optical coherence tomography angiography (OCTA). Some of the patients were examined with fundus fluorescein angiography (FFA). Clinical data and imaging characteristics from the OCT, OCTA, and FFA were analyzed retrospectively.ResultsWe found the hyperreflective structures surrounded by hyporeflective edges around the optic discs in 37 eyes. EDI-OCT results revealed hyperreflective structures surrounded by hyporeflective edges around the optic discs in all eyes. Typical hyperreflexia lesions occurred around the optic disc, located subretinally and above Bruch's membrane. OCTA revealed that the highly reflective perioptic material also had vascular structures.ConclusionEDI-OCT of PHOMS showed hyperreflective structures surrounded by hyporeflective edges around all of the optic discs. Infra-red photography showed temporal hyperreflexia. These characteristics can be seen in a variety of diseases and may be a relatively common feature revealed by EDI-OCT scanning. These characteristics may also be seen in elderly patients as well as children. PHOMS may be found in optic disc drusen (ODD), tilted disc syndrome (TDS), optic neuritis, ischemic optic neuropathy, and in white dot syndromes. Few patients may be developed into macular neovascularization (MNV). In order to improve the accuracy and robustness of the conclusions and provide better clinical guidance, we need to conduct more comprehensive research in the subsequent clinical work.

Background Nanomedicine is a promising new approach to cancer treatment that avoids the disadvantages of traditional chemotherapy and improves therapeutic indices. However, the lack of a real-time visualization imaging technology to monitor drug distribution greatly limits its clinical application. Image-tracked drug delivery is of great clinical interest; it is useful for identifying those patients for whom the therapy is more likely to be beneficial. This paper discusses a novel nanomedicine that displays features of nanoparticles and facilitates functional magnetic resonance imaging but is challenging to prepare. Results To achieve this goal, we synthesized an acylamino-containing amphiphilic block copolymer (polyethylene glycol-polyacrylamide-polyacetonitrile, PEG-b-P(AM-co-AN)) by reversible addition-fragmentation chain transfer (RAFT) polymerization. The PEG-b-P(AM-co-AN) has chemical exchange saturation transfer (CEST) effects, which enable the use of CEST imaging for monitoring nanocarrier accumulation and providing molecular information of pathological tissues. Based on PEG-b-P(AM-co-AN), a new nanomedicine PEG-PAM-PAN@DOX was constructed by nano-precipitation. The self-assembling nature of PEG-PAM-PAN@DOX made the synthesis effective, straightforward, and biocompatible. In vitro studies demonstrate decreased cytotoxicity of PEG-PAM-PAN@DOX compared to free doxorubicin (half-maximal inhibitory concentration (IC50), mean ~ 0.62 μg/mL vs. ~ 5 μg/mL), and the nanomedicine more efficiently entered the cytoplasm and nucleus of cancer cells to kill them. Further, in vivo animal experiments showed that the nanomedicine developed was not only effective against breast cancer, but also displayed an excellent sensitive CEST effect for monitoring drug accumulation (at about 0.5 ppm) in tumor areas. The CEST signal of post-injection 2 h was significantly higher than that of pre-injection (2.17 ± 0.88% vs. 0. 09 ± 0.75%, p Conclusions The nanomedicine with CEST imaging reflects the characterization of tumors and therapeutic functions has great potential medical applications.

The diagnostic performance difference between digital breast tomosynthesis (DBT) and conventional full-field digital mammography (FFDM) for breast suspicious calcifications from various populations is unclear. The objective of this study is to determine whether DBT exhibits the diagnostic advantage for breast suspicious calcifications from various populations compared with FFDM. Three hundred and five patients were enrolled (of which seven patients with bilateral lesions) and 312 breasts images were retrospectively analyzed by three radiologists independently. The postoperative pathology of breast calcifications was the gold standard. Breast cancer was diagnosed utilizing DBT and FFDM with sensitivities of 92.9% and 88.8%, specificities of 87.9% and 75.2%, positive predictive values of 77.8% and 62.1%, negative predictive values of 96.4% and 93.6%, respectively. DBT exhibited significantly higher diagnostic accuracy for benign calcifications compared with FFDM (87.9% vs 75.2%), and no advantage in the diagnosis of malignant calcifications. DBT diagnostic accuracy was notably higher than FFDM in premenopausal (88.4% vs 78.8%), postmenopausal (90.2% vs 77.2%), and dense breast cases (89.4% vs 81.9%). There was no significant difference in non-dense breast cases. In our study, DBT exhibited a superior advantage in dense breasts and benign calcifications cases compared to FFDM, while no advantage was observed in non-dense breasts or malignant calcifications cases. Thus, in the breast cancer screening for young women with dense breasts, DBT may be recommended for accurate diagnosis. Our findings may assist the clinicians in applying the optimal techniques for different patients and provide a theoretical basis for the update of breast cancer screening guideline., Graphical Abstract Unlabelled Image, Highlights • DBT exhibits higher diagnostic accuracy for benign calcifications compared to FFDM • DBT exhibits higher diagnostic accuracy in dense breast cases than FFDM • DBT exhibits higher diagnostic accuracy in premenopausal and postmenopausal cases • DBT has no advantage in non-dense breasts and malignant calcifications cases

Viruses exist wherever there is life. They can cause allergy, immune response, inflammation, and even fatal diseases directly or indirectly. Accumulating evidence shows that host RNA undergoes rapid degradation during virus infection. Herein, we focus on several possible mechanisms of infection-induced host RNA turnover, which seems to be a common strategy for both prokaryotic and eukaryotic viruses during the very early stage of infection and a potential application of live cell imaging on its visualization. Keywords: Virion, Bacteriophage, Host infection, Messenger RNA decay, Live cell imaging

Background Glutamate (GLU) is one of the most important excitatory neurotransmitters in central nervous system (CNS). GLU is involved in many CNS diseases, which is well reported that it is closely related to the infectious diseases in CNS. Brain abscess is a common disease in CNS. GLU chemical exchange saturation transfer MRI (GLUCEST) is used to explore the changes of glutamate concentration in the brain abscess models. Methods Firstly, a SD rat brain abscess model was established by using Staphylococcus aureus in the right frontal lobe of SD rats. Secondly, imaging of normal SD rats and brain abscess rats were obtained in Agilent 7.0T animal magnetic resonance scanner respectively. Finally, all data are processed on Matlab. Results GLUCEST clearly delineated brain abscess at Z spectra. The CEST map of the brain abscess rats showed that the glutamate CEST effect in the lesions was significantly higher than that in the normal SD rats (p Conclusions GLUCEST may provide new insight into brain abscess and help to improve the differential diagnosis.

Background: Early life stress (ELS) is associated with an increased risk of developing depression and anxiety disorders. Disturbances of the neurobiological glutamatergic system are implicated in depression; however, the long-term effects of early life stress on glutamate (Glu) metabolites remain unclear. Our study used 7T proton magnetic resonance spectroscopy (7T 1 HMRS) to detect metabolic Glu in a rat model to investigate maternal deprivation (MD)-induced ELS. Methods: MD was established in Sprague-Dawley rats by periodic separation from mothers and peers. Changes in the hippocampal volume and Glu metabolism were detected by 7T 1 HMRS after testing for depression-like behavior via open field, sucrose preference, and Morris water maze tests. Findings: Adult MD offspring exhibited depression-like behavior. Compared to control, the MD group exhibited reduced ratio of central activity time to total time and decreased sucrose consumption (18 ± 6 g vs. 31 ± 12 g, p = 0·02). MD rats spent less time in the fourth quadrant, where the platform was originally placed, in the Morris water maze test. According to 7T 1 HMRS, MD rats had elevated Glu and glutamate+glutamine (Glu+Gln) levels compared with the control group hippocampi, but Gln and gamma-aminobutyric acid (GABA), glutamate+glutamine (Glu+Gln) in the prefrontal cortex of MD rats showed a downward trend. Interpretation: Depression-like behavior and cognition deficits related to ELS may induce region-specific changes in Glu metabolism in the prefrontal cortex and hippocampus. The novel, noninvasive 7T 1 HMRS-identified associations between Glu levels and ELS may guide future clinical studies. Funding Statement: The Key Program of the National Natural Science Foundation of China, No. 30930027; Program of the National Natural Science Foundation of China, No. 60971075; Natural Science Foundation of Guangdong Province of China, Nos.S2011010005194 and 2015A030313444; Shantou University Scientific Research Foundation for the Doctoral Scholar of China, No.NTF10010; The Department of Education, Guangdong Government under the Top-tier University Development Scheme for Research and Control of Infectious Diseases of China, No. 2015034. Declaration of Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest. Ethics Approval Statement: All procedures used in the study were reviewed and approved by the Ethics Committee of School of Medicine, Shantou University Medical College, and comply with the National Institutes of Health’s Guide for the Care and Use of Laboratory Animals (NIH publication no. 85-23, revised 1985). In the handling and care of all animals, we followed the international guiding principles for animal research, as stipulated by the World Health Organization (WHO) Chronicle (World Health Organization, 1985), as adopted by the Laboratory Animal Center, Shantou University Medical College.

Additional file 1 CEST imaging of AM at different saturation power and time; structure of PEG-PAM-PAN@DOX; TEM imaging; linear regression equation was calculated from the absorptance of different DOX concentration; the relationship between different saturation power/time and CEST ratio% of PEG-PAM-PAN@DOX; the body weight of mice; H&E staining (Figures S1–S6).

Introduction The accurate diagnosis and monitoring of idiopathic Parkinson disease (PD), a progressive neurodegenerative disorder, has not been fully developed. This study sought to identify a neurochemical profile in multiple regions of the PD brain and healthy controls by proton magnetic resonance spectroscopy (1H‐MRS). We aimed to track changes of the brain neurochemical, quantify neuronal loss, and further determine the diagnostic value of 1H‐MRS. Methods PD patients and healthy controls recruited from Second Affiliated Hospital of Shantou University Medical College, Shantou, southern China, underwent 1H‐MRS. Chemical information was obtained for ratios of N‐acetylaspartate to creatine (NAA/Cr), NAA to choline (NAA/Cho), and Cho to Cr for substantia nigra, globus pallidus, prefrontal lobe, hippocampus, cuneus gyrus, and dorsal thalamus regions. Results Compared to the 20 healthy controls (12 male, age 58.75 ± 5.03 years), the 42 patients (21 male, age 61.60 ± 6.40 years) showed lower NAA/Cr and NAA/Cho ratios in substantia nigra, globus pallidus, prefrontal lobe, hippocampus, cuneus gyrus and dorsal thalamus regions (p

Previous studies suggested patients with bipolar depressive disorder (BDd) or unipolar depressive disorder (UDd) have cerebral metabolites abnormalities. These abnormalities may stem from multiple sub-regions of gray matter in brain regions. Thirteen BDd patients, 20 UDd patients and 20 healthy controls (HC) were enrolled to investigate these abnormalities. Absolute concentrations of 5 cerebral metabolites (glutamate-glutamine (Glx), N-acetylaspartate (NAA), choline (Cho), myo-inositol (mI), creatine (Cr), parietal cortex (PC)) were measured from 4 subregions (the medial frontal cortex (mPFC), anterior cingulate cortex (ACC), posterior cingulate cortex (PCC), and parietal cortex (PC)) of gray matter. Main and interaction effects of cerebral metabolites across subregions of gray matter were evaluated. For example, the Glx was significantly higher in BDd compared with UDd, and so on. As the interaction analyses showed, some interaction effects existed. The concentrations of BDds’ Glx, Cho, Cr in the ACC and HCs’ mI and Cr in the PC were higher than that of other interaction effects. In addition, the concentrations of BDds’ Glx and Cr in the PC and HCs’ mI in the ACC were statistically significant lower than that of other interaction effects. These findings point to region-related abnormalities of cerebral metabolites across subjects with BDd and UDd.

Objectives Bipolar disorder (BD) is a mental disorder characterized by periods of elevated mood and depression. Many individuals with BD are initially misdiagnosed and treated for unipolar depression (UD). In this study, we report direct comparisons between medication-free individuals with BD and those with UD in terms of the neurometabolites in the anterior cingulate cortex (ACC), medial prefrontal cortex (mPFC), parietal cortex (PC), and posterior cingulate cortex (PCC) of the brain. Methods Participants included medication-free patients with BD or UD, and matched healthy controls. All patients were in the depressive state and had similar symptoms. All subjects were subjected to a multi-voxel proton magnetic resonance spectroscopy procedure with a 3.0 T GE Signa MR scanner. After post-processing, the absolute concentrations of glycerophosphocholine + phosphocholine (GPC + PC), phosphocreatine + creatine (PCr + Cr), Glx (glutamate + glutamine), myo-inositol (MI), and N-acetyl aspartate (NAA) from the above brain regions were compared across the three groups. Results Patients with BD showed significantly higher levels of Glx in their ACC, lower GPC + PC, PCr + Cr, MI, and NAA in their PC, and lower NAA in their mPFC, compared to healthy controls; patients with UD presented significantly lower levels of GPC + PC, PCr + Cr, and NAA in their PCC, and lower Glx in their mPFC. All analyzed brain metabolites, except Glx, were significantly lower in the PC of patients with BD, whereas levels of GPC + PC, PCr + Cr, and NAA were significantly reduced in the PCC of patients with UD. Conclusions These results add to the evidence of brain metabolite differences in brains of patients with UD and BD which may be of help in differentiating these two mood disorders.

Cerebellar liponeurocytoma is a rare benign neuroepithelial tumour. We describe the case of a 50-year-old man presenting with signs of increased intracranial pressure and cerebellar dysfunction. Magnetic resonance imaging showed a heterogeneous, well-circumscribed cerebellar mass with a predominant adipose content. Diffusion-weighted imaging showed an isointense mass with a hyperintense rim. Craniotomy demonstrated a soft grey mass with intratumoral bright patchy yellow areas. Histological and immunohistochemical findings indicated an advanced neuronal, glial and focal lipomatous differentiation with a low level of mitotic activity.

Choroid plexus papillary carcinoma is a rare intracranial malignant epithelial tumor. We describe a case of choroid plexus tumor arising in the periventricular parenchyma. A 52-year-old man presented with headache for five months, aggravated by vomiting for three days. Brain computed tomography scan revealed an inhomogeneous density lesion in the right temporoparietal lobe with mild enhancement, and hemorrhage anterior to the lesion. Histological and immunohistochemical findings indicated a choroid plexus papillary carcinoma.

Nuclear Overhauser enhancement (NOE) is a type of magnetization transfer using cross-relaxation. It originates from mobile macromolecules, which may have relevance to the evaluation of tumor features. We studied the value of NOE imaging at 7 and 3 T and suggest a utility for diagnosing human brain tumors. Two types of protein solution at different concentrations and pH values, and six normal Sprague Dawley (SD) rats, were used to detect NOE signal with a 7 T scanner. Then, six healthy volunteers and 11 patients with brain tumors (six gliomas and five meningiomas) were included at 3 T. Z-spectra were measured and NOE weighted (NOE*) images were acquired with a three-offset measurement. Wide spectral separation was shown at both 7 T and 3 T delineating the NOE peak in the Z-spectrum. The concentration dependence and pH independence of NOE were confirmed in phantom experiments, and NOE values were greater in white matter than in gray matter in vivo. At 3 T, data indicated that NOE* maps were slightly hypointense in gliomas and were not obviously different from meningiomas. Thus, NOE imaging may help distinguish benign from malignant tumors, and as such may contribute to diagnosing brain tumors.

To investigate the activity of senescence-associated beta-galactosidase (SA-beta-GAL) in the hippocampus of aging rats. Hippocampi of 6-, 18-, and 24-month-old rats were observed by histochemical staining for SA-beta-GAL and cytochemical staining for SA-beta-GAL in cultured hippocampal neurons. The activity of SA-beta-GAL doubled in hippocampal pyramidal cells of the CA3 region in rats between 6 and 18 months (14.57+/-2.74% vs. 31.66+/-14.12% SA-beta-GAL-positive, respectively), and reached 50.76+/-14.41% positive at 24 months. The activity of SA-beta-GAL also increased as a function of time upon prolonged culture of cultured hippocampal neurons with 95% of cells being SA-beta-GAL-positive at 20 days in vitro. Interestingly, no SA-beta-GAL-positive cells were found in neurons of the hippocampal dentate gyrus, a neurogenic region of the brain, at any age examined. SA-beta-GAL can be used as a senescence biomarker in determining senescent neurons in hippocampal pyramidal cells of the CA3 region in advanced aging.

To study the transverse thoracic pedicle diameter of a Chinese population and to determine the feasibility and safety of transpedicular screw fixation. The authors studied the transverse pedicle diameter of the T1–T12 of the thoracic spine in a Chinese population using reformatted computed tomography. The data were compared with Caucasians and other Asians. The mean outer pedicle widths of the thoracic spine from T1 to T12 were 8.43, 6.65, 5.20, 4.44, 4.50, 4.87, 5.04, 5.32, 5.66, 6.65, 8.08 and 8.27 mm in males and 7.91, 6.03, 4.55, 3.91, 4.05, 4.31, 4.39, 4.60, 5.13, 5.67, 7.21 and 7.50 mm in females, respectively. Female patients have smaller dimensions compared with male patients. A significant percentage of patients have an outer pedicle width of less than 4.5 mm from T3 to T8, which is not suitable for transpedicular screw fixation with a 3.5 mm screw. The results of this study suggest that transpedicular screw fixation may not be suitable for the mid-thoracic regions in most Chinese females and that modified pedicle screw techniques or modified type of fixation is required in these patients. CT evaluation is a must before this procedure is performed.

Cerebellar liponeurocytoma is a rare benign neuroepithelial tumor. We describe the case of a 50- year-old man, presenting with signs of increased intracranial pressure and cerebellar dysfunction. Magnetic Resonance Imaging (MRI) showed a heterogeneous, well-circumscribed cerebellar mass with a predominant adipose content. Diffusion Weighted Imaging (DWI) showed an isointense mass with a hyperintense rim Craniotomy demonstrated a soft, gray mass with intratumoral bright patchy yellow areas. Histological and immunohistochemical findings indicated an advanced neuronal, glial and focal lipomatous differentiation with a low level of mitotic activity.

This paper aims to detect the normal standard of metabolic ratios in the Pons of healthy adult Chinese subjects by using proton magnetic resonance spectroscopy (1HMRS). Eighty healthy Chinese subjects were divided into four groups, containing of 20 subjects per decade, ranging 21 to 60 years. Spectra were obtained from at 1.5 T MR scanner by using a PRESS sequence with Repetition Time (TR)/ Echo Time (TE) of 1500/144 ms. Results: The total mean ratios of N-acetylasparate/ creatine- phosphocreatine(NAA/Cr), NAA/Cr+ choline- containing compound(Cho) and Cho/Cr in subjects ranging from 21 to 60 years were 2.127plusmn0.071, 0.811plusmn0.059 and 1.814plusmn0094, respectively. The metabolic ratios in men were higher than in women. However, there was no significant difference with respect to age or gender. The ratios of NAA/Cr, NAA/Cr+Cho, Cho/Cr in the Pons did not correlate with age or gender of healthy subjects.

Objective: To determine the normal mean reference normal value for metabolic ratios in the pons of healthy adult Chinese subjects by using proton magnetic resonance spectroscopy (1HMRS). Materials and methods: Eighty healthy Chinese subjects, ranging in age from 21 to 60 years, were divided into four groups, each containing 20 subjects per decade. The pons of every subject was scanned on single-voxel 1HMRS by using the point-resolved proton spectroscopy sequence (PRESS) with echo time (TE) = 144 ms and repetition time (TR) = 1500 ms. Results: The total mean ratios of N-acetylasparate/creatine–phosphocreatine (NAA/Cr), NAA/choline-containing compounds (Cho) and Cho/Cr in subjects ranging from 21 to 60 years were 2.13 ± 0.07, 1.22 ± 0.11 and 1.81 ± 0.09 respectively. The highest metabolite ratios were seen in the 41–50 year group. There was no significant difference with respect to age or gender. Conclusions: The ratios of NAA/Cr, NAA/Cho or Cho/Cr in the pons did not correlate with the age or gender of healthy subjects.

Purpose Functional MR imaging of the human cervical spinal cord was carried out on volunteers during alternated rest and a complex finger tapping task, in order to detect image intensity changes arising from neuronal activity. Methods Functional MR imaging data using single-shot fast spin-echo sequence (SSFSE) with echo time 42.4 ms on a 1.5 T GE Clinical System were acquired in eight subjects performing a complex finger tapping task. Cervical spinal cord activation was measured both in the sagittal and transverse imaging planes. Postprocessing was performed by AFNI (Analysis of Functional Neuroimages) software system. Results Intensity changes (5.5–7.6%) were correlated with the time course of stimulation and were consistently detected in both sagittal and transverse imaging planes of the cervical spinal cord. The activated regions localized to the ipsilateral side of the spinal cord in agreement with the neural anatomy. Conclusion Functional MR imaging signals can be reliably detected with finger tapping activity in the human cervical spinal cord using a SSFSE sequence with 42.4 ms echo time. The anatomic location of neural activity correlates with the muscles used in the finger tapping task.