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Episodic memory consists of a core event and the associated contexts. Although the role of the hippocampus and its neighboring regions in contextual representations during encoding has become increasingly evident, it remains unclear how these regions handle various context-specific information other than spatio-temporal contexts. Using high-resolution functional MRI, we explored the patterns of the medial temporal lobe (MTL) and cortical regions’ involvement during the encoding of various types of contextual information (i.e., journalism principle 5W1H): “Who did it?,” “Why did it happen?,” “What happened?,” “When did it happen?,” “Where did it happen?,” and “How did it happen?” Participants answered six different contextual questions while looking at simple experimental events consisting of two faces with one object on the screen. The MTL was divided to sub-regions by hierarchical clustering from resting-state data. General linear model analyses revealed a stronger activation of MTL sub-regions, the prefrontal lobe (PFC), and the inferior parietal lobule (IPL) during social (Who), behavioral (How), and intentional (Why) contextual processing when compared with spatio-temporal (Where/When) contextual processing. To further investigate the functional networks involved in contextual encoding dissociation, a multivariate pattern analysis was conducted with features selected as the task-based connectivity links between the hippocampal subfields and PFC/IPL. Each social, behavioral, and intentional contextual processing was individually and successfully classified from spatio-temporal contextual processing, respectively. Thus, specific contexts in episodic memory, namely social, behavior, and intention, involve distinct functional connectivity patterns that are distinct from those for spatio-temporal contextual memory [ABSTRACT FROM AUTHOR]

Context: Early identification of the response of prolactinoma patients to dopamine agonists (DA) is crucial in treatment planning.Objective: To develop a radiomics model using an ensemble machine learning classifier with conventional magnetic resonance images (MRIs) to predict the DA response in prolactinoma patients.Design: Retrospective study.Setting: Severance Hospital, Seoul, Korea.Patients: A total of 177 prolactinoma patients who underwent baseline MRI (109 DA responders and 68 DA nonresponders) were allocated to the training (n = 141) and test (n = 36) sets. Radiomic features (n = 107) were extracted from coronal T2-weighed MRIs. After feature selection, single models (random forest, light gradient boosting machine, extra-trees, quadratic discrimination analysis, and linear discrimination analysis) with oversampling methods were trained to predict the DA response. A soft voting ensemble classifier was used to achieve the final performance. The performance of the classifier was validated in the test set.Results: The ensemble classifier showed an area under the curve (AUC) of 0.81 [95% confidence interval (CI), 0.74-0.87] in the training set. In the test set, the ensemble classifier showed an AUC, accuracy, sensitivity, and specificity of 0.81 (95% CI, 0.67-0.96), 77.8%, 78.6%, and 77.3%, respectively. The ensemble classifier achieved the highest performance among all the individual models in the test set.Conclusions: Radiomic features may be useful biomarkers to predict the DA response in prolactinoma patients. [ABSTRACT FROM AUTHOR]

BACKGROUND: Only a limited number of neuroimaging studies have explored the effects of ambient air pollution in adults. The prior studies have investigated only cortical volume, and they have reported mixed findings, particularly for gray matter. Furthermore, the association between nitrogen dioxide (NO2) and neuroimaging markers has been little studied in adults. OBJECTIVES: We investigated the association between long-term exposure to air pollutants (NO2, particulate matter (PM) with aerodynamic diameters of =10 µm (PM10) and =2.5 µm (PM2.5), and neuroimaging markers. RESULTS: A 10-µg/m³ increase in PM10 was associated with reduced thicknesses in the frontal [–0.02 mm (95% CI: –0.03, –0.01)] and temporal lobes [–0.06 mm (95% CI: –0.07, –0.04)]. A 10-µg/m³ increase in PM2.5 was associated with a thinner temporal cortex [–0.18 mm (95% CI: –0.27, –0.08)]. A 10-ppb increase in NO2 was associated with reduced thicknesses in the global [–0.01 mm (95% CI: –0.01, 0.00)], frontal [–0.02 mm (95% CI: –0.03, –0.01)], parietal [–0.02 mm (95% CI: –0.03, –0.01)], temporal [–0.04 mm (95% CI: –0.05, –0.03)], and insular lobes [–0.01 mm (95% CI: –0.02, 0.00)]. The air pollutants were also associated with increased thicknesses in the occipital and cingulate lobes. Subcortical structures associated with the air pollutants included the thalamus, caudate, pallidum, hippocampus, amygdala, and nucleus accumbens. DISCUSSION: The findings suggest that long-term exposure to high ambient air pollution may lead to cortical thinning and reduced subcortical volume in adults. [ABSTRACT FROM AUTHOR]

Background: Aging is the most important risk factor of development of dementia in Parkinson's disease (PD), but there are no data on clinical and radiological heterogeneity of PD dementia (PDD) depending on age at onset. Objectives: The goal of this study was to examine whether patients with PDD are clinically and radiologically heterogeneous depending on age at onset. Methods: A total of 116 patients with PD dementia and 121 age- and sex-matched normal controls were enrolled. The subjects were divided into early-onset (EOPDD; n = 39) and late-onset (LOPDD; n = 77) PDD with the respective age-matched control group based on a cutoff value of 70 years. The effects of diagnosis, age, and their interaction on neuropsychological tests, cortical thickness, and substantia innominata volume were assessed using analysis of covariance. Results: EOPDD patients had a poorer cognitive performance on digit backward, forward span test (p = 0.011 and 0.05), and visual recognition memory function (p = 0.012) compared with LOPDD patients. Additionally, EOPDD patients exhibited cortical thinning in the left anterior cingulate gyrus and the right inferior temporal gyrus, with significantly decreased normalized substantia innominata volume (p = 0.044). Conclusions: Our data demonstrated that EOPDD patients exhibit poorer cognitive performance and more severe atrophy in the cortex and substantia innominata, implying that EOPDD may be a distinct phenotype different from LOPDD. [ABSTRACT FROM AUTHOR]

A lymphoplasmacyte-rich meningioma (LPRM) is an extremely rare variant of meningioma. Here, we report a case of atypical LPRM with increased mitosis in a 55-year-old man. Preoperative magnetic resonance imaging suggested meningioma with brain invasion in the left tentorium cerebelli. Histological examination revealed sclerotic fibrosis and dense lymphoplasmacytic infiltration; based on these findings, the differential diagnosis included LPRM and fibroinflammatory lesions of the dura, such as idiopathic hypertrophic pachymeningitis (IHP), IgG4-related disease (IgG4-RD), and Rosai-Dorfman disease. Epithelial membrane antigen (EMA) immunostaining highlighted sheets of meningothelial cells, which strongly supported the diagnosis of meningioma. Although brain invasion was suspected in radiologic image, no histologic evidence of brain invasion was found. However, the mitoses were observed to be 8/10 high power fields, along with increased Ki-67 labeling index with focal spontaneous necrosis, and the final pathologic diagnosis was atypical LPRM. IgG4-RD was ruled out, because IgG4 counts and the IgG4:IgG ratio of plasma cells did not meet the diagnostic criteria for IgG4-RD. To date, only one case of LPRM with brain invasion has been reported as atypical LPRM. This case is therefore the second case of atypical LPRM with increased mitosis that histologically mimicked IHP. [ABSTRACT FROM AUTHOR]

Cardiovascular fibrosis resulted from pressure overload or ischemia could alter myocardial stiffness and lead to ventricular dysfunction. Fluorescently labeled collagen-binding protein CNA 35, derived from the surface component of Staphylococcus aureus, and a novel synthetic biphenylalanine containing peptide are applied to stain fibrosis associated collagen and myocytes, respectively. Detailed pathological characteristics of cardiovascular fibrosis could be identified clearly in 2 hours. This staining pair requires only simple staining and brief washing, generating less than 10 ml of waste. The image information collected by this novel fluorescent staining pair is compatible with it collected by the traditional Masson's Trichrome and Picrosirius Red staining which are widely used to stain cardiovascular fibrosis and isolated cells. [ABSTRACT FROM AUTHOR]

Boron-doped diamond electrodes covered with a nanostructured Pt nanoparticle-polyaniline composite have been fabricated and employed as sensitive amperometric sensors with low detection limit. A highly conductive boron-doped diamond thin film (BDD) was prepared by chemical vapor deposition, and its morphology was characterized by scanning electron microscopy and transmission electron microscopy. The nanostructured composite layer was grown on the BDD electrode by electrochemical deposition of polyaniline and Pt nanoparticles. Glucose oxidase (GOx) was then adsorptively immobilized on the modified BDD electrode. The biosensor displays a large surface area, high catalytic activity of the Pt nanoparticles, efficient electron mediation through the conducting polymer, and low background current of the electrode. The biosensor exhibits an excellent response to glucose, with a broad linear range from 5.9 μM to 0.51 mM, a sensitivity of 5.5 μA·mM, a correlation coefficient (R) of 0.9947, and a detection limit of 0.10 μM. The apparent Michaelis-Menten constant (K) and the maximum current density of the electrode are 4.1 mM and 0.021 mA, respectively. This suggests that the immobilized GOx possesses a higher affinity for glucose at the lower K, and that the enzymatic reaction rate constitutes the rate-limiting step of the response. [ABSTRACT FROM AUTHOR]

Background: Extranodal nasal-type natural killer (NK)/T-cell lymphoma (NKTL) is a rare, but distinct clinical entity in Asian populations. However, it is not uncommon for NKTL to be belatedly or postoperatively diagnosed because radiologists are not familiar with its radiological features. Purpose: To investigate the computed tomography (CT) findings in patients with extranodal nasal-type NKTL involving the head and neck. Material and Methods: Twenty-nine patients (18 male, 11 female; mean age 51.5 years) with pathologically proven extranodal nasal-type NKTL were enrolled in this study. Two head-and-neck radiologists retrospectively evaluated the CT scans with special attention to the primary site, the extent of involvement, and patterns of the lesions (i.e., morphologic features, ulceration or necrosis, and bone destruction). Results: The cases of nasal-type NKTL consisted of primary tumors arising from the sinonasal cavity in 13 patients (45%), the naso/oropharynx in three patients (10%), and simultaneous involvement in the nasal cavity and naso/oropharynx in 13 patients (45%). Fourteen patients (48%) showed tumor extension into adjacent structures. Of the 26 patients with involvement of the nasal cavity, 18 (69%) presented with an infiltrative pattern, seven (27%) with a polypoid pattern, and one (4%) with a combined pattern. Areas of necrosis within the tumor were observed in six patients (21%), bone destruction in five (17%), and regional lymphadenopathies in two (7%). Conclusion: Extranodal NKTL may be initially suggested by CT findings in the head and neck. Clinicians should consider these findings indicative of the possibility of NKTL, and should perform a histopathologic confirmation to establish a diagnosis. [ABSTRACT FROM AUTHOR]

Nitric oxide (NO) was applied to broccoli (Brassica oleracea L. var. italica) florets and analyzed its effect on chlorophyll degradation during postharvest senescence. Florets were treated with 1000 μL/L of NO for 5 h and placed in darkness at 20 °C. During storage, the NO treatment delayed yellowing and retarded the onset of chlorophyll degradation. The activity of lipoxygenase was not related to the development of yellowing during storage. However, the accumulation of malondialdehyde, which could be used as an index of lipid peroxidation, was higher in the control than observed in the NO treatment. In untreated broccoli florets during storage, lipid peroxidation influenced the yellowing of broccoli florets while NO-treated florets maintained chlorophyll levels and decreased lipid peroxidation. [ABSTRACT FROM AUTHOR]

The color-forming ability of amino acids with thiosulfinate in crushed garlic was investigated. We developed reaction systems for generating pure blue pigments using extracted thiosulfinate from crushed garlic and onion and all 22 amino acids. Each amino acid was reacted with thiosulfinate solution and was then incubated at 60 °C for 3 h to generate pigments. Unknown blue pigments, responsible for discoloration in crushed garlic cloves ( Allium sativum L.), were separated and tentatively characterized using high-performance liquid chromatography (HPLC) and a diode array detector ranging between 200 and 700 nm. Blue pigment solutions exhibited 2 maximal absorbance peaks at 440 nm and 580 nm, corresponding to yellow and blue, respectively, with different retention times. Our findings indicated that green discoloration is created by the combination of yellow and blue pigments. Eight naturally occurring blue pigments were separated from discolored garlic extracts using HPLC at 580 nm. This suggests that garlic discoloration is not caused by only 1 blue pigment, as reported earlier, but by as many as 8 pigments. Overall, free amino acids that formed blue pigment when reacted with thiosulfinate were glycine, arginine, lysine, serine, alanine, aspartic acid, asparagine, glutamic acid, and tyrosine. Arginine, asparagine, and glutamine had spectra that were more similar to naturally greened garlic extract. [ABSTRACT FROM AUTHOR]

A deformable registration method is proposed for registering a normal brain atlas with images of brain tumor patients. The registration is facilitated by first simulating the tumor mass effect in the normal atlas in order to create an atlas image that is as similar as possible to the patient's image. An optimization framework is used to optimize the location of tumor seed as well as other parameters of the tumor growth model, based on the pattern of deformation around the tumor region. In particular, the optimization is implemented in a multiresolution and hierarchical scheme, and it is accelerated by using a principal component analysis (PCA)-based model of tumor growth and mass effect, trained on a computationally more expensive biomechanical model. Validation on simulated and real images shows that the proposed registration framework, referred to as ORBIT (optimization of tumor parameters and registration of brain images with tumors), outperforms other available registration methods particularly for the regions close to the tumor, and it has the potential to assist in constructing statistical atlases from tumor-diseased brain images. [ABSTRACT FROM AUTHOR]

Vitamin C plays a crucial role in the suppression of proliferation of several types of cancer. Over-expression of cyclooxygenase (COX)-2 and type I insulin-like growth factor (IGF) receptor are important for proliferation and protection from apoptosis in malignancies. However, its specific mechanisms, especially the interaction between COX-2 expression and IGF-I axis mediated by vitamin C, remain yet to be clarified. Therefore, we investigated the effects of vitamin C on the proliferation of melanoma cells via the modulation of COX-2 expression and IGF-I axis. As a result, we found that 1.0 mM vitamin C inhibits the proliferation of SK-MEL-2 without induction of apoptosis. At that moment, IGF-II production was decreased, followed by the inhibition of COX-2 activity. IGF-IR expression was also down-regulated by vitamin C treatment. It coincided with the result from the inhibition of COX-2 by NS-398 and COX-2 siRNA. In addition, the decreased IGF-IR expression by vitamin C was restored by the treatment of recombinant prostaglandin E2. Finally, we determined whether the signal pathway would be involved in vitamin C-induced IGF-II and IGF-IR down-regulation. When the cells were exposed to SB203580, a specific inhibitor of p38 MAPK, COX-2 expression was dramatically recovered. In addition, phosphorylated p38 MAPK was increased after vitamin C treatment. Taken together, vitamin C suppresses proliferation of the human melanoma cell line SK-MEL2 via the down-regulation of IGF-II production and IGF-IR expression, which is followed by the activation of p38 MAPK and the inhibition of COX-2 expression. J. Cell. Physiol. 216: 180–188, 2008. © 2008 Wiley-Liss, Inc. [ABSTRACT FROM AUTHOR]

The aquaporins (AQP) are water channel proteins playing a major role in transcellular and transepithelial water movement. Recently, the role of AQPs in human carcinogenesis has become an area of great interest. Here, by immunohistochemistry (IHC), we have found an expression of AQP5 protein in 35.3% (IHC-score: ⩾1, 144/408) of the resected NSCLC tissue samples. Cases with AQP5-positive status (IHC-score: ⩾2) displayed a higher rate of tumor recurrence than negative ones in NSCLC (54.7% vs. 35.1%, p = 0.005) and worse disease-free survival (p = 0.033; OR = 1.52; 95%CI:1.0422.23). Further in vitro invasion assay using BEAS-2B and NIH3T3 cells stably transfected with overexpression constructs for full length wild-type AQP5 (AQP5) and its two mutants, N185D which blocks membrane trafficking and S156A which blocks phosphorylation on Ser156, showed that AQP5 induced cell invasions while both mutants did not. In BEAS-2B cells, the expression of AQP5 caused a spindle-like and fibroblastic morphologic change and losses of cell-cell contacts and cell polarity. Only cells with AQP5, not either of two mutants, exhibited a loss of epithelial cell markers and a gain of mesenchymal cell markers. In a human SH3-domains protein array, cellular extracts from BEAS-2B with AQP5 showed a robust binding activity to SH3- domains of the c-Src, Lyn, and Grap2 C-terminal. Furthermore, in immunoprecipitation assay, activated c-Src, phosphorylated on Tyr416, showed a stronger binding activity to cellular extracts from BEAS-2B with AQP5 compared with N185D or S156A mutant. Fluorescence in situ hybridization (FISH) analysis failed to show evidence of genomic amplification, suggesting AQP5 expression as a secondary event. Based on these clinical and molecular observations, we conclude that AQP5, through its phosphorylation on Ser156 and subsequent interaction with c-Src, plays an important role in NSCLC invasion and, therefore, may provide a unique opportunity for developing a novel therapeutic target as well as a prognostic marker in NSCLC. [ABSTRACT FROM AUTHOR]

To determine if defects in mitochondrial respiratory chain enzyme complexes (MRCs) contribute to the etiology of childhood epilepsy. We reviewed the clinical and laboratory features of 48 epileptic patients (23 male, 25 female) with MRC defects that were confirmed by biochemical assays using muscle biopsies. (1) Thirty-five cases (72.9%) were MRC I deficient, one case (2.1%) was MRC II deficient, 11 cases (22.9%) were MRC IV deficient, and one case (2.1%) had combined MRC I and IV deficiencies. (2) In our clinical diagnosis, there were 10 cases (20.8%) with Leigh disease and one case each with myopathy, encephalopathy, lactic acidosis, stroke-like episodes (MELAS) or Alpers' disease (2.1%). Most of the remaining cases (75.0%) had uncategorized mitochondrial cytopathy with nonspecific encephalopathy. (3) For epileptic classification, there were two cases (4.2%) of Ohtahara syndrome, 10 cases (20.8%) of West syndrome, 12 cases (25.0%) of Lennox-Gastaut syndrome, two cases (4.2%) of Landau-Kleffner syndrome, 14 cases (29.2%) of generalized epilepsy, and eight cases (16.7%) of partial epilepsy. (4) The mean age of seizure onset was 2.68 ± 2.21 (range: 1 month – 5.5 years). (5) Magnetic resonance imaging (MRI) showed diffuse cortical atrophy in 34 cases (70.8%), basal ganglia signal changes in 18 cases (37.5%) and thalamus signal changes in 12 cases (25.0%). (6) A ketogenic diet produced clinical improvements, including seizure reduction and global functional improvement in 75% of 24 patients. MRC defects are one of the important causes of probably symptomatic childhood epilepsy. A ketogenic diet should be carefully considered for treatment of intractable epilepsy related to MRC defects. [ABSTRACT FROM AUTHOR]

Abstract  The osteogenic potential of autologous cultured osteoblasts mixed with fibrin when transplanted to bone defects was evaluated. Radial shaft defects over 15 mm were made in 30 New Zealand white rabbits. A total of 15 rabbits in the control group underwent an iliac bone graft and 15 rabbits in the experimental group underwent an autologous cultured osteoblast injection mixed with fibrin. Both groups were compared radiologically and 5 rabbits in each group were sacrificed for histological evaluation using H-E and Masson’s trichrome stain at 3, 6, and 9 weeks. Osteogenesis in the control group progressed more rapidly than in the experimental group. However, at 9 weeks, bone formation in both groups were similar and showed no significant difference in terms of the amount of bone formation and the quality of bone union. Autologous cultured osteoblast transplantation mixed with fibrin in bone defects was found to produce bone efficiently. [ABSTRACT FROM AUTHOR]

The endovascular treatment of cerebral aneurysms with coils poses significant technical challenges, particularly with respect to wide-necked aneurysms. We present the results of our initial experiences in using a stent for endovascular treatment of aneurysms, with an emphasis on potential applications, technical aspects, and associated complications. Twenty-three wide-necked aneurysms from 22 patients were treated during the 13-month study period. Seven patients presented with subarachnoid hemorrhage. Aneurysms were located at the internal carotid artery ( n=14), the vertebral artery ( n=3), the basilar artery ( n=5), and the middle cerebral artery ( n=1). A Neuroform stent2 was used for stent-assisted procedures. Premedication with antithrombotic agents was available for unruptured cases. Postprocedural antithrombotic medication was prescribed for all patients. Nineteen aneurysms were primarily stented, followed by coil placement. For five of these aneurysms, stenting was performed subsequent to failure of an attempt to frame with an initial coil. Stenting for the remaining four aneurysms was performed as a rescue procedure to prevent the migration of previously placed coils. Complete occlusion was obtained in ten aneurysms, nearly complete occlusion (95% or more occluded) in 11 aneurysms, and partial occlusion (less than 95% occluded) in one aneurysm. In one aneurysm, we failed to navigate the microcatheter into the aneurysmal sac through the interstices of the stent. Stent thrombosis was noted during the procedure in one patient. Hemorrhagic complication on the 25th day after the procedure was noted in one patient. No procedure-related complications were observed during the procedure or during follow-up in the remaining 20 patients, including seven patients who did not receive antithrombotic agents prior to endovascular treatment owing to recent subarachnoid hemorrhage. To overcome the technical limitation in the coiling of wide-necked aneurysms, stent-assisted coil embolization may be a technically feasible and relatively safe method, even though longer periods of follow-up are required. [ABSTRACT FROM AUTHOR]

We aimed in this study to assess the clinical usefulness of fractional anisotropy (FA) maps in the evaluation of lacunar infarctions in striatum, internal capsule and thalamus. We retrospectively reviewed 28 patients (18 men, 10 women; mean age 63 years) who had acute lacunar infarction in striatum, internal capsule and thalamus on diffusion weighted MR imaging (DWI). Fractional anisotropy (FA) maps were generated in addition to conventional T2 weighted images (T2WI) and trace maps of DWI. Two radiologists reviewed the location of infarcts in combination with and without FA maps. Exact location of infarction was determined by FA maps, i.e. on the white band of internal capsule or outside the internal capsule. Accuracy and inter-observer agreement on determination of the location of infarction was evaluated. Accuracy of infarct localization by T2WI-DWI only was varied from 72 to 91% according to the observers. Inter-observer agreement value was moderate (Kappa=0.446), when images were interpreted by T2WI-DWI only. Clinical manifestation of each lesions were varied, but sensory motor stroke was mainly observed in thalamic lesion (50%), while pure motor hemiparesis was predominant in the case of infarct involving internal capsule, corona radiata (91%) and basal ganglia (83%). The FA map is useful in the evaluation of lacunar lesions in striatum, internal capsule and thalamus. Clinical presentation varies according to the exact location of lacunar infarctions, and more accurate diagnosis can be made by FA maps as well as conventional T2-weighted image and DWI. [ABSTRACT FROM AUTHOR]

A 63-year-old woman complained of a growing neck mass. Sonography revealed a solid and cystic mass in the right thyroid lobe. Color Doppler study and computed tomography revealed anechoic cystic portions within the thyroid nodule to be a pseudoaneurysm arising from the right inferior thyroid artery. The only identifiable risk factor was a past thyroid needle biopsy performed approximately 5 years previously according to the patient's recollection. Right lobectomy was performed and the pseudoaneurysm was treated without complication. [ABSTRACT FROM AUTHOR]

Antiphospholipid syndrome (APS) has been recognized as the leading cause of vascular thrombosis in children. The syndrome may occur in isolation or in association with an underlying systemic disease, particularly systemic lupus erythematosus. Less than 1% of patients with APS present with a life-threatening condition resulting from thrombosis in multiple organs and subsequent multiorgan failure, which is defined as catastrophic APS. Early recognition of APS is essential because prompt and appropriate management can result in favorable outcome. We present the case of a 7-year-old girl with APS who presented with cerebral, femoral, and renal involvement in the second week of the disease progress. The patient presented with multiple thrombotic episodes and rapidly progressive renal failure. Renal cortical infarction was diagnosed by magnetic resonance imaging. [ABSTRACT FROM AUTHOR]

We have built a tabletop frequency modulation (FM) communication system that uses a laser field as the carrier. Voice information is encoded on the laser beam using an acousto-optic modulator, and it is extracted by a Michelson-type interferometer and a FM radio. This system can easily be converted to an intensity-modulated communication system. We discuss similar systems based on phase or polarization modulation using an electro-optic modulator. [ABSTRACT FROM AUTHOR]