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The effects of a computer-aided diagnosis (CAD) system based on quantitative intensity features with magnetic resonance (MR) imaging (MRI) were evaluated by examining radiologists' performance in grading gliomas. The acquired MRI database included 71 lower-grade gliomas and 34 glioblastomas. Quantitative image features were extracted from the tumor area and combined in a CAD system to generate a prediction model. The effect of the CAD system was evaluated in a two-stage procedure. First, a radiologist performed a conventional reading. A sequential second reading was determined with a malignancy estimation by the CAD system. Each MR image was regularly read by one radiologist out of a group of three radiologists. The CAD system achieved an accuracy of 87% (91/105), a sensitivity of 79% (27/34), a specificity of 90% (64/71), and an area under the receiver operating characteristic curve (Az) of 0.89. In the evaluation, the radiologists' Az values significantly improved from 0.81, 0.87, and 0.84 to 0.90, 0.90, and 0.88 with p = 0.0011, 0.0076, and 0.0167, respectively. Based on the MR image features, the proposed CAD system not only performed well in distinguishing glioblastomas from lower-grade gliomas but also provided suggestions about glioma grading to reinforce radiologists' confidence rating., Competing Interests: The authors have declared that no competing interests exist.

Background and Objectives: A computer-aided diagnosis (CAD) system based on quantitative magnetic resonance imaging (MRI) features was developed to evaluate the malignancy of diffuse gliomas, which are central nervous system tumors., Methods: The acquired image database for the CAD performance evaluation was composed of 34 glioblastomas and 73 diffuse lower-grade gliomas. In each case, tissues enclosed in a delineated tumor area were analyzed according to their gray-scale intensities on MRI scans. Four histogram moment features describing the global gray-scale distributions of gliomas tissues and 14 textural features were used to interpret local correlations between adjacent pixel values. With a logistic regression model, the individual feature set and a combination of both feature sets were used to establish the malignancy prediction model., Results: Performances of the CAD system using global, local, and the combination of both image feature sets achieved accuracies of 76%, 83%, and 88%, respectively. Compared to global features, the combined features had significantly better accuracy (p = 0.0213). With respect to the pathology results, the CAD classification obtained substantial agreement κ = 0.698, p < 0.001., Conclusions: Numerous proposed image features were significant in distinguishing glioblastomas from lower-grade gliomas. Combining them further into a malignancy prediction model would be promising in providing diagnostic suggestions for clinical use., (Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.)

Background: Tumors with epicenter in the thalamus occur in about 4 % of pediatric brain tumors. The histological diagnosis is mainly gliomas. Among them, low-grade glioma (LGG) constituted of a significant entity of the tumors (Cuccia et al., Childs Nerv Syst 13:514-521, 1997; Puget et al., J Neurosurg 106:354-362, 2007; Bernstein et al., J Neurosurg 61:649-656, 1984; Bilginer et al., Childs Nerv Syst 30:1493-1498, 2014). Since Kelly's report in 1989, >90 % resection of thalamic tumors were achieved in reported series (Ozek and Ture, Childs Nerv Syst 18:450-6, 2002; Villarejo et al., Childs Nerv Syst 10:111-114, 1994; Moshel et al., Neurosurgery 61:66-75, 2007; Albright, J Neurosurg 100(5 Suppl Pediatrics): 468-472, 2004; Kelly, Neurosurgery 25:185-195, 1989; Drake et al., Neurosurgery 29: 27-33, 1991)., Materials and Methods: Sixty-nine cases of thalamic tumors in children were retrospectively reviewed. There were 25 cases of LGGs. We analyzed our experience and correlated it with reported series., Results: Summing up of 4 reported series and the present series, there were 267 cases of thalamic tumors in children. Among these tumors, 107 (40.1 %) were LGGs and 91 (34.1 %) were low-grade astrocytomas (LGAs). In the present series, all of the 25 LGGs were LGAs that consisted of 11 pilocytic astrocytomas (PAs) and 14 diffuse astrocytomas (DAs). Six cases received biopsy sampling only. The remaining 19 cases received different degrees of surgical resection via several approaches. Radical (>90 %) resection was achieved better in PAs comparing with DAs. There was no operative mortality. Two patients had increased neurological deficits. In a mean follow-up period of 11.9 years, three patients died of tumor progression and one patient died of anaplastic change. The 5- and 10-year overall survival (OS) was 87.1 and 87.1 %, respectively., Conclusion: Thalamic LGGs are mainly LGAs and are indolent. The rate of >90 % resection was relatively low in the present series. By applying contemporary diagnostic MRI studies, surgical facilities, and appropriate approaches in selective cases, we may try maximum neuroprotective radical (>90 %) resection.

Background: Absence seizures are a subtype of epileptic seizures clinically characterized by transient alterations in states of consciousness and by electroencephalography indicating diffuse spike-wave discharges (SWD). Conventional brain magnetic resonance imaging (MRI) is not routinely used to establish the diagnosis, but rather to rule out other diseases. The present study investigated tissue integrity in children with SWD epilepsy using diffusion tensor imaging (DTI)., Methods: Magnetic resonance imaging (MRI)-DTI was conducted in 18 patients with absence seizures and 10 control participants. Brain areas were evaluated using diffusion maps, and fractional anisotropy (FA), mean diffusivity (MD), parallel diffusivity (λ||), and perpendicular diffusivity (λ⊥) values were extracted and analyzed. Tractography at the regions of abnormal diffusion indices was then reconstructed in each group, and tract symmetry was evaluated by an index of asymmetry (AI). Statistical analyses were performed using nonparametric Mann-Whitney U tests, with p values < 0.05 indicating statistical significance., Results: Compared to the control group, patients with SWD epilepsy had lower FA values and higher MD values at the genu of the corpus callosum. There was also a stronger negative correlation between MD and FA values at the genu of the corpus callosum in patients than in control participants. The AI for the fiber tracts through the genu of the corpus callosum in the SWD group was significantly higher than that of the control group, indicating that tract distribution was more asymmetric in patients with epilepsy. There were no significant differences between groups in diffusion indices for other brain areas., Conclusion: We observed microstructural changes in the genu of the corpus callosum, as well as reduced FA values, increased λ⊥ values, increased MD values, and asymmetric distribution of fiber tracts, indicating that DTI is more sensitive than conventional MRI to detect brain abnormalities in children with absence seizures., (Copyright © 2015. Published by Elsevier B.V.)

In radio-over-fiber systems, optical single-sideband (SSB) modulation signals are preferred to optical double-sideband (DSB) modulation signals for fiber distribution in order to mitigate the microwave power fading effect. However, typically adopted modulation schemes generate DSB signals, making DSB-to-SSB conversion necessary before or after fiber distribution. This study investigates a semiconductor laser at stable locking dynamics for such conversion. The conversion relies solely on the nonlinear dynamical interaction between an input DSB signal and the laser. Only a typical semiconductor laser is therefore required as the key conversion unit, and no pump or probe signal is necessary. The conversion can be achieved for a broad tunable range of microwave frequency up to at least 60 GHz. In addition, the conversion can be carried out even when the microwave frequency, the power of the input DSB signal, or the frequency of the input DSB signal fluctuates over a wide range, leading to high adaptability and stability of the conversion system. After conversion, while the microwave phase quality, such as linewidth and phase noise, is mainly preserved, a bit-error ratio down to 10 -9 is achieved for a data rate up to at least 8 Gb/s with a detection sensitivity improvement of more than 1.5 dB.

A mid-aged male presented with progressive lower urinary tract symptoms (LUTS) for years. Huge prostate with low serum prostate-specific antigen (PSA) level was detected. The specimen from transurethral resection revealed surprising pathology finding as malignant peripheral nerve sheath tumor (MPNST). Considering its huge size (more than 300 gm) and location, we prescribed neoadjuvant chemotherapy firstly. The tumor became regressive and then radical surgical resection was achieved. Adjuvant multimodality treatment including concurrent chemoradiotherapy (CCRT) and target therapy was given. However, he expired about one year later. MPNST originating from prostate is very rare and seldom reported before. We here present this extremely rare disease and share our treatment experience.

Objective: For unknown reasons, there is discordance among previous reports with regard to the association of contrast medium (CM) with nephropathy and the incidence of nephropathy after contrast-enhanced CT. This study aimed to determine the frequency of and possible factors related to CM-induced nephropathy in hospitalized patients, with an emphasis on detailing coprescriptions with nephrotoxic potential., Materials and Methods: Of 1378 inpatients who underwent CT, 208 (15.1%) met the inclusion criteria: receipt of IV iodinated CM and baseline serum creatinine level obtained within 45 days before and within 2 weeks after CT. Patient demographics, clinical characteristics, comorbidity, nephrotoxic comedications (nine classes of drugs), and type of CM administered were retrospectively reviewed. Relationships between CM-induced nephropathy (serum creatinine level increase ≥ 25% or ≥ 0.5 mg/dL after CT) and risk factors were assessed by stepwise multivariate logistic regression., Results: The cohort of 208 subjects had a high number of comorbidities (mean [± SD], 5.8 ± 3.5 diagnoses) and a high rate of receiving nephrotoxic comedications (45.2%). CM-induced nephropathy was detected in 27 (13.0%) patients. Concurrent use of four nephrotoxic agents (odds ratio [OR], 26.250; 95% CI, 3.673-233.993) was the most influential factor associated with CM-induced nephropathy; other predictors included preexisting renal disease (OR, 8.218; 95% CI, 1.622-42.357), baseline serum creatinine level less than 0.7 or greater than or equal to 1.3 mg/dL (OR, 3.463; 95% CI, 1.341-9.025), and hemoglobin level less than 9.3 g/dL (OR, 3.141; 95% CI, 1.087-8.946)., Conclusion: Among the known risk factors, such as preexisting renal disease, high serum creatinine level, and low hemoglobin level, a statistically significant association was identified between CM-induced nephropathy and concurrent receipt of four nephrotoxic medications. Relevant preventive measures are warranted for individuals at risk, especially hospitalized patients receiving multiple nephrotoxic medications who require contrast-enhanced CT.

Purpose: To test if MPO-Gd, a gadolinium-based magnetic resonance (MR) imaging probe that is sensitive and specific for the proinflammatory and oxidative enzyme myeloperoxidase (MPO), which is secreted by certain inflammatory cells, is more sensitive than diethylenetriaminepentaacetic acid (DTPA)-Gd in revealing early subclinical and chronic disease activity in the brain in experimental autoimmune encephalomyelitis (EAE), a mouse model of multiple sclerosis., Materials and Methods: The protocol for animal experiments was approved by the institutional animal care committee. A total of 61 female SJL mice were induced with EAE. Mice underwent MPO-Gd- or DTPA-Gd-enhanced MR imaging on days 6, 8, and 10 after induction, before clinical disease develops, and during chronic disease at remission and the first relapse. Brains were harvested at these time points for flow cytometric evaluation of immune cell subtypes and immunohistochemistry. Statistical analysis was performed, and P < .05 was considered to indicate a significant difference., Results: MPO-Gd helps detect earlier (5.2 vs 2.3 days before symptom onset, P = .004) and more (3.1 vs 0.3, P = .008) subclinical inflammatory lesions compared with DTPA-Gd, including in cases in which there was no evidence of overt blood-brain barrier (BBB) breakdown detected with DTPA-Gd enhancement. The number of MPO-Gd-enhancing lesions correlated with early infiltration of MPO-secreting monocytes and neutrophils into the brain (r = 0.91). MPO-Gd also helped detect more lesions during subclinical disease at remission (5.5 vs 1.3, P = .006) and at the first relapse (9.0 vs 2.7, P = .03) than DTPA-Gd, which also correlated well with the presence and accumulation of MPO-secreting inflammatory cells in the brain (r = 0.93)., Conclusion: MPO-Gd specifically reveals lesions with inflammatory monocytes and neutrophils, which actively secrete MPO. These results demonstrate the feasibility of detection of subclinical inflammatory disease activity in vivo, which is different from overt BBB breakdown., ((©) RSNA, 2014)

Objective: The purpose of this article is to use a mechanism-based approach to review the neuroimaging findings of abusive head trauma to infants. Advanced neuroimaging provides insights into not only the underlying mechanisms of craniocerebral injuries but also the long-term prognosis of brain injury for children on whom these injuries have been inflicted., Conclusion: Knowledge of the traumatic mechanisms, the key neuroimaging findings, and the implications of functional imaging findings should help radiologists characterize the underlying causes of the injuries inflicted, thereby facilitating effective treatment.

Coding productivity is expected to drop significantly during the lead-up to and in the initial stages of ICD-10-CM/PCS implementation, now expected to be delayed until October 1, 2015. This study examined the differences in coding productivity between ICD-9-CM and ICD-10-CM/PCS for hospital inpatient cases matched for complexity and severity. Additionally, interrater reliability was calculated to determine the quality of the coding. On average, coding of an inpatient record took 17.71 minutes (69 percent) longer with ICD-10-CM/PCS than with ICD-9-CM. A two-tailed T-test for statistical validity for independent samples was significant (p = .001). No coder characteristics such as years of experience or educational level were found to be a significant factor in coder productivity. Coders who had received more extensive training were faster than coders who had received only basic training. Though this difference was not statistically significant, it provides a strong indication of significant return on investment for staff training time. Coder interrater reliability was substantial for ICD-9-CM but only moderate for ICD-10-CM/PCS, though some ICD-10-CM/PCS cases had complete interrater (coder) agreement. Time spent coding a case was negatively correlated with interrater reliability (-0.425 for ICD-10-CM and -0.349 for ICD-10-PCS). This finding signals that increased time per case does not necessarily translate to higher quality. Adequate training for coders, as well as guidance regarding time invested per record, is important. Additionally, these findings indicate that previous estimates of initial coder productivity loss with ICD-10-CM/PCS may have been understated.

Primary melanoma of the central nervous system is a rare melanocytic tumor typically located in the leptomeninges. We report a 57-year-old woman with an intracranial leptomeningeal melanoma who presented with myoclonic seizures. Brain CT scan and MRI revealed a hemorrhagic intracranial tumor. The tumor was completely removed and leptomeningeal melanoma was proven pathologically. Follow-up imaging studies up to 19 months showed no recurrence of the disease. Here we present radiological, gross, and pathological images of leptomeningeal melanoma, discuss its characteristics, and review the relevant literature., (Copyright © 2013 Elsevier Ltd. All rights reserved.)

Background: Enzymatic activity measurements of the highly oxidative enzyme myeloperoxidase (MPO), which is implicated in many diseases, are widely used in the literature, but often suffer from nonspecificity and lack of uniformity. Thus, validation and standardization are needed to establish a robust method that is highly specific, sensitive, and reproducible for assaying MPO activity in biological samples., Principal Findings: We found conflicting results between in vivo molecular MR imaging of MPO, which measures extracellular activity, and commonly used in vitro MPO activity assays. Thus, we established and validated a protocol to obtain extra- and intracellular MPO from murine organs. To validate the MPO activity assays, three different classes of MPO activity assays were used in spike and recovery experiments. However, these assay methods yielded inconsistent results, likely because of interfering substances and other peroxidases present in tissue extracts. To circumvent this, we first captured MPO with an antibody. The MPO activity of the resultant samples was assessed by ADHP and validated against samples from MPO-knockout mice in murine disease models of multiple sclerosis, steatohepatitis, and myocardial infarction. We found the measurements performed using this protocol to be highly specific and reproducible, and when performed using ADHP, to be highly sensitive over a broad range. In addition, we found that intracellular MPO activity correlated well with tissue neutrophil content, and can be used as a marker to assess neutrophil infiltration in the tissue., Conclusion: We validated a highly specific and sensitive assay protocol that should be used as the standard method for all MPO activity assays in biological samples. We also established a method to obtain extra- and intracellular MPO from murine organs. Extracellular MPO activity gives an estimate of the oxidative stress in inflammatory diseases, while intracellular MPO activity correlates well with tissue neutrophil content. A detailed step-by-step protocol is provided.

Four new 11-nor-iridoids, 6-O-p-hydroxybenzoyl-10-deoxyeucommiol (1), 6-O-benzoyl-10-deoxyeucommiol (2), 6-O-benzoyl-dihydrocatalpolgenin (a mixture of 3 and 4), as well as two known iridoids, ningpogenin (5) and 6-O-p-hydroxybenzoylaucubin (6), were isolated from the fruits of Crescentia cujete Linn. The structures of these compounds were established on the basis of spectroscopic analysis.

To recognize the DNA sequence and mine the hidden information to achieve the classification of organisms are viewed as a difficult work to biologists. As we know, the amino acids are the basic elements to construct DNA. Hence, if the codon usage of amino acids can be analyzed well, the useful information about classification of organisms may be obtained. However, if we choose too many amino acids to perform the clustering analysis, the high dimensions also lead the clustering analysis to be a complicated structure. Hence, in this study, we will incorporate the principle component analysis and fuzzy-ART clustering techniques into constructing an integrated approach. The useful information about organisms classification based on the codon usage can be mined by using the proposed approach. Finally, we also employ a case including 18 bacteria to demonstrate the rationality and feasibility of our proposed approach.

Guajadial (1), a novel caryophyllene-based meroterpenoid, was isolated from the Leaves of Psidium guajava (guava). The structure and relative stereochemistry of guajadial (1) were elucidated by extensive spectroscopic analysis. A possible biosynthetic pathway for 1 was proposed.

A cDNA clone GmPM4 which encodes mRNA species in mature or dry soybean seeds was characterized. DNA sequence analysis shows that the deduced polypeptides have a molecular mass of 68 kDa. GmPM4 proteins have a relatively high amino acid sequence homology with a major biotinylated protein isolated from pea seeds, SBP65, but both of these proteins differ markedly from that of presently known biotin enzymes. The accumulation of GmPM4 mRNA is detectable in the leaf primodium and the vascular tissues of the hypocotyl-radicle axis of mature seeds, and the GmPM4 proteins are present at high levels in dry and mature soybean seeds, but not in fresh immature seeds. It degrades rapidly at the early stage of seed germination. These proteins are boiling-soluble and biotinylated when they are present endogenously in soybean seeds; however, the same recombinant protein expressed in Escherichia coli is boiling-soluble, but it is not biotinylated.