Accelerated Nonenhanced 3D T1-MPRAGE Using Wave-Controlled Aliasing in Parallel Imaging for Infant Brain Imaging.

BACKGROUND AND PURPOSE: MPRAGE is the most commonly used sequence for high-resolution 3D T1-weighted imaging in pediatric patients. However, its longer scan time is a major drawback because pediatric patients are prone to motion and frequently require sedation. This study compared nonenhanced accelerated MPRAGE using wave-controlled aliasing in parallel imaging (wave-T1-MPRAGE) with standard MPRAGE in infants. MATERIALS AND METHODS: We retrospectively evaluated 68 infants (mean age, 1.78 [SD. 1.70] months) who underwent nonenhanced standard and wave-T1-MPRAGE. Two neuroradiologists independently assessed each image for image quality, artifacts, myelination degree, and anatomic delineation using the 4-point Likert scale. For diagnostic performance, both observers determined whether nonenhancing lesions were present in the brain parenchyma in 2 types of nonenhanced MPRAGE sequences. RESULTS: Wave-T1-MPRAGE showed a significantly lower mean score and lower interobserver agreement for overall image quality and anatomic delineation than standard MPRAGE (P< .001 for each). However, there were no significant differences between the 2 types of MPRAGE sequences for motion artifacts (P = .90 for observer 1, P = .14 for observer 2) and degree of myelination (P = .16 for observer 1, P = .32 for observer 2). Among the nonenhancing pathologic lesions observed on standard MPRAGE by both observers, only 2 were missed on wave-T1-MPRAGE, and they were very tiny, faint, nonhemorrhagic WM injuries. CONCLUSIONS: Although wave-T1-MPRAGE showed lower overall image quality than standard MPRAGE, the diagnostic performance for nonenhancing parenchymal lesions was comparable. Wave-T1-MPRAGE could be an alternative for diagnosing intracranial lesions in infants, with marked scan time reduction.

Usefulness of Wave-CAIPI for Postcontrast 3D T1-SPACE in the Evaluation of Brain Metastases.

BACKGROUND AND PURPOSE: High-resolution postcontrast 3D T1WI is a widely used sequence for evaluating brain metastasis, despite the long scan time. This study aimed to compare highly accelerated postcontrast 3D T1-weighted sampling perfection with application-optimized contrasts by using different flip angle evolution by using wave-controlled aliasing in parallel imaging (wave-T1-SPACE) with the commonly used standard high-resolution postcontrast 3D T1-SPACE for the evaluation of brain metastases. MATERIALS AND METHODS: Among the 387 patients who underwent postcontrast wave-T1-SPACE and standard SPACE, 56 patients with suspected brain metastases were retrospectively included. Two neuroradiologists assessed the number of enhancing lesions according to lesion size, contrast-to-noise ratiolesion/parenchyma, contrast-to-noise ratiowhite matter/gray matter, contrast ratiolesion/parenchyma, and overall image quality for the 2 different sequences. RESULTS: Although there was no significant difference in the evaluation of larger enhancing lesions (>5 mm) between the 2 different sequences (P = .66 for observer 1, P = .26 for observer 2), wave-T1-SPACE showed a significantly lower number of smaller enhancing lesions (<5 mm) than standard SPACE (1.61 [SD, 0.29] versus 2.84 [SD, 0.47] for observer 1; 1.41 [SD, 0.19] versus 2.68 [SD, 0.43] for observer 2). Furthermore, mean contrast-to-noise ratiolesion/parenchyma and overall image quality of wave-T1-SPACE were significantly lower than those in standard SPACE. CONCLUSIONS: Postcontrast wave-T1-SPACE showed comparable diagnostic performance for larger enhancing lesions (>5 mm) and marked scan time reduction compared with standard SPACE. However, postcontrast wave-T1-SPACE showed underestimation of smaller enhancing lesions (<5 mm) and lower image quality than standard SPACE. Therefore, postcontrast wave-T1-SPACE should be interpreted carefully in the evaluation of brain metastasis.

Tumor immune microenvironment is influenced by frameshift mutations and tumor mutational burden in gastric cancer.

PURPOSE: Immunoscore can effectively predict prognosis in patients with colon cancer; however, its clinical application is limited. We modified the Immunoscore and created a tumor immune microenvironment (TIM) classification system for gastric carcinoma. Unlike previous studies that used small sample sizes or focused on particular immune-cell subtypes, our simplified system enables pathologists to classify gastric carcinomas intuitively using H&E-stained sections. METHODS: Samples from 326 patients with advanced gastric carcinoma were reviewed and analyzed by pathologists using simple determination and digital image analysis. Comprehensive results of cancer-panel sequencing, Epstein-Barr‒virus (EBV) status, and PD-L1, HER2, ATM, PTEN, MET, FGFR2, and EGFR immunohistochemistry were evaluated with respect to the TIM class. RESULTS: The TIM was classified as "hot" (n = 22), "immunosuppressed" (n = 178), "excluded" (n = 83), or "cold" (n = 43). TIM category was significantly associated with numbers of frameshift mutations (P < 0.001) and high tumor mutational burden (P < 0.004), and predicted overall survival. It was also significantly associated with age, histological type, degree of fibrosis, PD-L1 expression, loss of ATM and PTEN expression (P < 0.001), sex, EBV positivity, and HER2 overexpression (P < 0.04). "Hot" tumors were frequent in PD-L1 expressing and EBV-positive samples, and in those with ATM and PTEN loss. "Excluded" tumors were frequent in HER2-positive cases, whereas "cold" tumors were more frequent in younger patients with poorly cohesive histology and high fibrosis levels. CONCLUSIONS: TIM classification system for gastric carcinoma has prognostic significance and results in classes that are associated with molecular characteristics.

Usefulness of the Delay Alternating with Nutation for Tailored Excitation Pulse with T1-Weighted Sampling Perfection with Application-Optimized Contrasts Using Different Flip Angle Evolution in the Detection of Cerebral Metastases: Comparison with MPRAGE Imaging.

BACKGROUND AND PURPOSE: Contrast-enhanced T1-weighted sampling perfection with application-optimized contrasts by using different flip angle evolution (SPACE) with the delay alternating with nutation for tailored excitation (DANTE) pulse could suppress the blood flow signal and provide a higher contrast-to-noise ratio of enhancing lesion-to-brain parenchyma than the MPRAGE sequence. The purpose of our study was to evaluate the usefulness of SPACE with DANTE compared with MPRAGE for detecting brain metastases. MATERIALS AND METHODS: Seventy-one patients who underwent contrast-enhanced SPACE with DANTE and MPRAGE sequences and who were suspected of having metastatic lesions were included. Two neuroradiologists determined the number of enhancing lesions, and diagnostic performance was evaluated using figure of merit, sensitivity, positive predictive value, interobserver agreement, and reading time. Contrast-to-noise ratiolesion/parenchyma and contrast-to-noise ratiowhite matter/gray matter were also assessed. RESULTS: SPACE with DANTE (observer one, 328; observer two, 324) revealed significantly more small (<5 mm) enhancing lesions than MPRAGE (observer one, 175; observer two, 150) (P < 0.001 for observer 1, P ≤ .0001 for observer 2). Furthermore, SPACE with DANTE showed significantly higher figure of merit and sensitivity and shorter reading time than MPRAGE for both observers. The mean contrast-to-noise ratiolesion/parenchyma of SPACE with DANTE (52.3 ± 43.1) was significantly higher than that of MPRAGE (17.5 ± 19.3) (P ≤ .0001), but the mean contrast-to-noise ratiowhite matter/gray matter of SPACE with DANTE (-0.65 ± 1.39) was significantly lower than that of MPRAGE (3.08 ± 1.39) (P ≤ .0001). CONCLUSIONS: Compared with MPRAGE, SPACE with DANTE significantly improves the detection of brain metastases.

Pointwise Encoding Time Reduction with Radial Acquisition with Subtraction-Based MRA during the Follow-Up of Stent-Assisted Coil Embolization of Anterior Circulation Aneurysms.

BACKGROUND AND PURPOSE: Time-of-flight MR angiography, though widely used after coil embolization, is associated with limitations owing to magnetic susceptibility and radiofrequency shielding following stent-assisted coil embolization. We evaluated the pointwise encoding time reduction with radial acquisition (PETRA) sequence in subtraction-based MRA (qMRA) using an ultrashort TE relative to TOF-MRA during the follow-up of stent-assisted coil embolization for anterior circulation aneurysms. MATERIALS AND METHODS: Twenty-five patients (3 men and 22 women; mean age, 59.1 ± 14.0 years) underwent stent-assisted coil embolization for anterior circulation aneurysms and were retrospectively evaluated using TOF-MRA and PETRA qMRA data from the same follow-up session. Two neuroradiologists independently reviewed both MRA findings and subjectively graded flow within the stents (relative to the latest DSA findings) and occlusion status (complete occlusion or neck/aneurysm remnant). Interobserver and intermodality agreement for TOF-MRA and PETRA qMRA were evaluated. RESULTS: The mean score for flow visualization within the stents was significantly higher in PETRA qMRA than in TOF-MRA (P < .001 for both observers), and good interobserver agreement was reported (κ = 0.63). The aneurysm occlusion status of PETRA qMRA (observer 1, 92.0%; observer 2, 88.0%) was more consistent with DSA than with TOF-MRA (observer 1, 76.0%; observer 2, 80.0%), and there was a better intermodality agreement between DSA and PETRA qMRA than between DSA and TOF-MRA. CONCLUSIONS: These findings indicate that PETRA qMRA is a useful follow-up technique for patients who have undergone stent-assisted coil embolization for anterior circulation aneurysms.

The impact of the National Denture Service on oral health-related quality of life among poor elders.

The objective of this study was to assess the effects of the Korean National Denture Service (NDS) for poor elderly people requiring dentures on oral health-related quality of life (OHRQOL). Data from follow-up studies were collected from 439 subjects at eight public health centres who answered every question of a questionnaire, and the OHRQOL was measured at the baseline and at 3-month follow-up after receiving the NDS according to the type of denture provision. The multivariate linear mixed model with a public health centre as a random effect for the score change of Oral Health Impact Profile (OHIP)-14K was carried out to confirm the factors related to the improvement in OHRQOL. The mean OHIP-14K was 28.60 at the baseline time points, and there was a decrease in the OHIP-14 scores to 21.14 ± 12.52 at the 3-month follow-up of the removable partial denture beneficiaries. The changes in OHIP-14K among complete denture beneficiaries were 21.53 ± 12.01 for previously dentate subjects and 22.54 ± 11.12 for edentate subjects. The multivariate linear mixed model of dentate subjects demonstrated that the improvement in the OHRQOL was associated with the number of remaining teeth, satisfaction with denture and self-reported oral health status after 3 months. In the case of the edentate model, satisfaction with denture was the only factor related to the improvement in OHRQOL. This study revealed considerable improvement in OHRQOL among poor elderly people after NDS. Satisfaction with provision of dentures was associated with improvement in the OHRQOL.

Factors influencing the concentration of cytokines during liver transplantation.

Not only does the underlying disease that requires surgery constitute a significant stress to the human body, but also the surgery itself serves as a stressor. Cytokine secretion is activated in response to the surgical stress during liver transplantation. We examined 44 patients to compare cytokine levels, according to the underlying diseases causing liver failure (viral hepatitis vs alcoholic hepatitis), examining whether the values differed according to the model for end-stage liver disease (MELD) score [high (≥20) vs low (<20)]. Pro-inflammatory cytokines tumor necrosis factor (TNF)-α, interleukin (IL)1ß, and IL-6 and anti-inflammatory cytokines IL-4 and IL-10 were quantified using sandwich enzyme- linked immunoassays at three times: (1) after inducing anesthesia, (2) 60 minutes after the start of the anhepatic period, and (3) 60 minutes after reperfusion. No difference in the level of any cytokine measured in our study was detected at any time point between the viral and the alcoholic hepatitis groups. Among the high MELD group, IL-1ß and IL-4 contents were higher than in the low MELD group at all time points (P < .05). IL-10 concentrations at time 1 and TNF-α at time 2 were higher among the high MELD group (P < .05). In conclusion, the severity of the inflammatory and stress reactions expressed as cytokine concentrations did not differ according to the underlying liver disease, but did associate with the MELD score.

Determination of enantiomeric amphetamines as metabolites of illicit amphetamines and selegiline in urine by capillary electrophoresis using modified beta-cyclodextrin.

The determination of enantiomeric amphetamine and methamphetamine in urine samples is important in order to distinguish use of the prescription drug selegiline (metabolized to R(-)-A and R(-)-MA) from the illicit use of S(+)-A and S(+)-MA. For the analysis of enantiomeric amphetamine (A) and methamphetamine (MA) in biological samples, the optimization of analytical condition was performed by capillary electrophoresis using chiral selectors including beta-cyclodextrin, carboxymethyl-beta-cyclodextrin and 2-hydroxypropyl-beta-cyclodextrin. We have examined the factors to obtain the best chiral resolutions, separation efficiency and sensitivity, and wide concentration linearity. Optimum resolutions were achieved using 100 mM phosphate buffer, pH 2.5, containing 10 mM of carboxymethyl-beta-cyclodextrin. This method was applied for the quantitative determination of enantiomeric amphetamine and methamphetamine in urine samples obtained from patients taking illicit amphetamines or from rats and patients taking selegiline. Acceptable quantitative results in terms of resolution, precision, sensitivity and linearity were obtained from the real urine samples containing wide-ranging concentrations of A and MA by using two concentrations of internal standards, alpha(+)- (1 microg/ml) and beta-phenylethylamine (50 microg/ml).

Application of micellar electrokinetic capillary chromatography for the determination of benzoic acid and its esters in liquid formula medicines as preservatives.

We described a method for the simultaneous determination of preservatives including benzoic acid, methyl-, ethyl- and propyl-benzoate by micellar electrokinetic capillary chromatography (MECC). The factors affecting the reproducibility in the quantitative analysis of pharmaceuticals by MECC were investigated by varying the running buffer and washing condition in-between runs. Preservatives in liquid formula medicines have been determined by optimum MECC condition using p-hydroxy benzoic acid as an internal standard. The reproducibility of this method was acceptable as a validate method for the quality control of pharmaceuticals (RSD < 2%). Routine quantitative analysis of pharmaceuticals using MECC could be possible with well characterized reproducible procedure.

Quaternary structural analysis of nucleoside diphosphate kinases using capillary electrophoresis.

Capillary electrophoresis was used to monitor the quaternary structure and structural changes by denaturants of nucleoside diphosphate kinase (NDP kinase). NDP kinase from human erythrocyte consists of two kinds of polypeptide chains: A (Nm23-H1) and B (Nm23-H2), which are the products of nm23-H1 and -H2 genes, respectively. Structural characteristics of native NDP kinase, recombinant Nm23-H1 and -H2 were examined using capillary electrophoresis employing high pH running buffer in an uncoated fused-silica capillary as a separation column. The results were compared with those of the conventional sodium dodecyl sulfate and non-denaturing polyacrylamide gel electrophoresis. It shows that capillary electrophoresis is a possible tool to investigate protein structure, including the quaternary structure. This protocol was applied to the investigation of the denaturation process of each enzyme by denaturants (6 M urea or heating to 70 degrees C) and to the monitoring of the interaction between denatured Nm23-H1 and -H2. The structural information of NDP kinase obtained by analysis using capillary electrophoresis is valuable for understanding its suggested biological function as a tumor metastasis suppressor and c-myc transcription factor, etc.