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Large-sized crystals and state-of-the-art photosensors are desirable to cope with low environmental radioactivity (e.g., 1-2 Bq∙m-3137Cs in surface seawater) for homeland security purposes. We compared the performances of two different gamma-ray detector assemblies, GAGG crystal + silicon photomultiplier (SiPM) and NaI(Tl) crystal + photomultiplier tube, for our mobile in-situ ocean radiation monitoring system. We performed energy calibration, followed by water tank experiments with varying the depth of a137Cs point source. Experimental energy spectra were compared with MCNP-simulated spectra with identical setup and the consistency was validated. We finally assessed the detection efficiency and minimum detectable activity (MDA) of the detectors. Both GAGG and NaI detectors exhibited favorable energy resolutions (7.98 ± 0.13% and 7.01 ± 0.58% at 662 keV, respectively) and MDAs (33.1 ± 0.0645 and 13.5 ± 0.0327 Bq∙m-3 for 24-h 137Cs measurement, respectively). Matching the geometry of the GAGG crystal with that of the NaI crystal, the GAGG detector outperformed the NaI detector. The results demonstrated that the GAGG detector is potentially advantageous over the NaI detector in detection efficiency and compactness.

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The supernatant from rat intestinal acetone powder (RIAP) was used as a source of mammalian glucosidases to determine the digestion properties of glycemic-carbohydrates. We hypothesized that many glucosidases are still anchored to the precipitated-intestinal tissues with available enzymes, and developed a method using the RIAP suspension to optimize the in vitro carbohydrate digestion model. The glucose production from various types of glycemic ingredients by RIAP suspension showed that this carbohydrate-hydrolysis model using the entire spectrum of glucosidases can be applied in an in vitro assay to determine carbohydrate quality from glycemic food products at the mammalian level. This approach better mimics the mammalian situation compared to other assays to determine the glycemic-carbohydrate digestion properties that employ fungal/microbial glucosidases that have different hydrolytic activities compared to mammalian enzymes. The method can also be used to determine the inhibitory effects of α-glucosidase inhibitors to attenuate the post-prandial blood glucose level.

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Starch digestion in the gastrointestinal tract has different properties depending on its botanical source. In this study, corn, wheat, rice, and potato starches were used to test the digestion properties of mammalian mucosal α-glucosidase in an in vitro assay, and their physiological effects were investigated in male C57BL/6 mice. The results clearly demonstrated that potato starch caused the lowest rates of glucose generation, suggesting that it can attenuate the postprandial glucose spike. Interestingly, a potato starch-based diet caused significantly (P < 0.05) lower weight gain and fat accumulation compared to diets based on other starches, through increased insulin sensitivity. This result suggests that potato starch-based products can be used to regulate postprandial blood glucose levels, aiding in the control of metabolic diseases.

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OBJECTIVE: The purpose of this article is to retrospectively compare the accuracy of MRI and CT in characterizing lipid-poor adrenal adenomas with respect to lesion-attenuation values measured on unenhanced CT. MATERIALS AND METHODS: Fifty-two lipid-poor adrenal masses measuring greater than 10 HU on unenhanced CT were identified in 52 patients who underwent both chemical-shift MRI and washout CT. Accuracies using the adrenal-to-spleen ratio (< 0.71) or signal intensity index (> 16.5%) for MRI and using absolute (≥ 60%) or relative (≥ 40%) percentage washout for CT were calculated to determine which modality was more accurate for lipid-poor adenoma characterization. Sensitivities of MRI and CT were also compared according to the lesion-attenuation values measured on unenhanced CT. Follow-up imaging or histologic diagnosis was used as the standard reference. The McNemar test was used to compare the accuracies of CT and MRI. RESULTS: Lipid-poor adrenal masses consisted of 37 adenomas and 15 nonadenomas. The sensitivities and specificities for adenoma on MRI versus CT were 75.7% (28/37) versus 100% (37/37) and 60.0% (9/15) versus 80.0% (12/15), respectively. CT achieved a higher accuracy than did MRI (p = 0.008). The sensitivities for adenomas measuring 20 HU or less on unenhanced CT were 100% (12/12) in both MRI and CT, whereas those measuring more than 20 HU were 64.0% (16/25) and 100% (25/25) in MRI and CT, respectively. CONCLUSION: MRI is equivalent to CT for characterizing adenomas measuring 20 HU or less on unenhanced CT. However, MRI is inferior to CT for adenomas measuring more than 20 HU because of decreased MR sensitivity.

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PURPOSE: To prospectively assess the usefulness of diffusion-weighted magnetic resonance imaging (MRI) with background body signal suppression (DWIBS) at 3T for the preoperative evaluation of endometrial cancer. MATERIALS AND METHODS: Fifty-two consecutive patients with biopsy-proven endometrial cancer were examined with a 3T MR scanner, followed by a hysterectomy. MR examinations included T2-weighted (T2WI), DWIBS, and dynamic contrast-enhanced T1-weighted imaging (DCEI). The apparent diffusion coefficient (ADC) was calculated in the tumor and normal myometrium. According to tumor grade, the mean ADC of the tumor was analyzed. The depth of myometrial invasion was independently assessed by two radiologists for three MRI datasets on a five-point scale. RESULTS: The mean ADC of the tumors was significantly lower than that of normal myometrium (P < 0.001). The mean ADC of grades 2 or 3 was significantly lower than grade 1 (P < 0.01). For predicting myometrial invasion, the specificity, accuracy, and area under the curve of combined T2WI and DWIBS in both readers were similar to DCEI (P > 0.05). Interreader agreement in all MRI datasets was excellent. CONCLUSION: DWIBS at 3T has potential for being an effective method for the preoperative evaluation of endometrial cancer.

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OBJECTIVES: To investigate the factors related to the successful computed tomography-guided nodule localization for subsequent nodule excision. METHODS: We retrospectively reviewed the medical records for 181 patients who had undergone computed tomography-guided nodule localization using hook wire and subsequent video-assisted thoracic surgery resection for lung nodules. The demographic factors, nodule factors, and technical factors were reviewed to determine what affects effective nodule localization for video-assisted thoracic surgery resection using both univariate and multivariate models. RESULTS: A total of 174 patients were included in our study. Successful localization was accomplished in 166 patients (95%). Univariate analysis implicated patient age, nodule solidity, zonal location, and a sufficient distance between the hook wire tip and pleural surface as significant factors for successful localization. Multivariate analysis focused on the distance between the wire tip and pleural surface as the sole independent factor for successful localization (P = .012). CONCLUSIONS: The distance between the hook wire tip and pleural surface was the major significant factor for successful computed tomography-guided nodule localization for subsequent video-assisted thoracic surgery resection. Thus, the localization of a hook wire adjacent to a target nodule with sufficient depth from the pleural surface is crucial to the success of the procedure.

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BACKGROUND: Three-dimensional (3D) turbo spin-echo (TSE) images have been used in imaging of the extremities and comparable diagnostic performance to two-dimensional (2D) TSE images has been reported in several studies. However, comparison of the 3D isotropic TSE intermediate-weighted sequence and 3D FFE sequence in terms of image quality has not been investigated. PURPOSE: To compare the image quality of a 3D isotropic TSE intermediate-weighted sequence with refocusing control (volume isotropic turbo spin echo acquisition [VISTA]) and a 3D isotropic fast-field echo (FFE) sequence of the knee joint. MATERIAL AND METHODS: 3.0 T knee MRI with VISTA and 3D FFE sequences was performed in 10 healthy volunteers (3 men, 7 women; age range 26-30 years). Two radiologists with specialties in the musculoskeletal system assessed tissue contrast between the fluid-cruciate ligament (F-L), fluid-meniscus (F-M), and fluid-cartilage (F-C) based on a 4-point scale (1, poor; 2, fair; 3, good; and 4, excellent). Statistical analysis for inter-observer agreement and differences in grades in tissue contrast between VISTA and 3D FFE images (Wilcoxon signed-rank) were performed. For a quantitative analysis, the signal-to-noise ratio (SNR) was obtained by imaging phantom and noise-only image. Image contrast ratios (CRs) were calculated between F-L, F-M, and F-C in volunteer images of VISTA and 3D FFE and compared statistically with a paired t-test. RESULTS: Based on qualitative analysis, VISTA had statistically superior grades of tissue contrast in F-L (P < 0.001) and F-M (P < 0.001). 3D FFE had superior but not statistically significant (P = 0.317) grades in F-C. Based on quantitative analysis, the SNR of the phantom imaging was higher in VISTA than that in 3D FFE (28.18 vs. 14.90). VISTA had superior CRs in F-L (P < 0.001) and F-M (P < 0.001). 3D FFE had superior CR in F-C (P = 0.038). CONCLUSION: The VISTA sequence was superior in tissue contrast between F-M and F-L, and 3D FFE was superior in tissue contrast between F-C, subjectively and quantitatively.

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BACKGROUND: Progressive multifocal leukoencephalopathy (PML) is a demyelinating central nervous system disease caused by JC virus (JCV) reactivation in immunocompromised patients. The disease course of PML is often progressive, fatal and at present, there are few reports on successful treatment outcomes. CASE REPORT: A 45-year-old man with systemic sarcoidosis presented with rapidly progressive dementia and right hemiparesis. The patient was diagnosed with PML as confirmed via brain biopsy and JCV PCR. With a combination treatment of cidofovir and mirtazapine, there was significant improvement of neurological symptoms without measurable functional deficit. CONCLUSION: This case suggests that dual therapy with cidofovir and mirtazapine might be an effective treatment option in PML patients with sarcoidosis.

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BACKGROUND: There are very few reports regarding the use of 3D rotational angiography (3D RA) in embolization of renal artery aneurysms (RAAs). No valuable data have been reported on the follow-up result of coil embolization for RAAs on computed tomography (CT). Purpose To evaluate the clinical and multidetector computed tomography (MDCT) follow-up results of renal artery aneurysms treated by detachable coil embolization using 3D RA. MATERIAL AND METHODS: Six patients diagnosed with RAAs were included. Five patients underwent detachable coil embolization. Five patients underwent 3D RA and the parameters used for planning endovascular treatment obtained by 2D CT, reformatted 3D CT angiography (3D CTA), 2D digital subtraction angiography (2D DSA) and 3D RA were compared. The postembolization MDCT follow-up findings were analyzed retrospectively. RESULTS: The technical success rate for detachable coil embolization was 40%. The 3D CTA showed the dome-to-neck ratio (DNR) and tangential view of the renal artery aneurysm in five patients (83.3%) and the 2D CT showed it in four (66.7%). An optimal working angle assessment could not be obtained on the 2D CT and 3D CTA. The 3D RA showed the DNR, tangential view, and optimal working angle in all patients. Renal infarction occurred in three patients and postprocedural hypertension developed in two patients during the follow-up period. CONCLUSION: The 3D RA was useful in preoperative determination of adequate working angle for detachable coil embolization of RAAs. Late complications of detachable coil embolization for RAAs were renal infarction and hypertension.

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Pancreatic arteriovenous malformations (AVM) are extremely rare diseases frequently complicated by gastrointestinal hemorrhage. While surgical resection of affected lesion is preferred for the treatment of pancreatic AVM, angiographic intervention can be used as an alternative treatment, especially in surgically high-risk patients. We experienced a patient with pancreatic AVM manifested by hemobilia and biliary sepsis. Superior mesenteric and common hepatic arteriography showed pancreaticoduodenal AVM composed of nidus supplied by numerous fine feeding arteries and of draining veins encircling the common bile duct (CBD). Hemobilia was controlled by transportal coil embolization of draining veins of AVM around the CBD. Herein, we report this case with the review of literatures.

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[reaction: see text]. Inter- and intramolecular titanium-mediated coupling reactions of N-acylpyrroles are reported for convenient functionalization of terminal olefins. Comparison with the Kulinkovich reaction of esters and other carboxylic acid derivatives is also included.

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