PURPOSE: To evaluate the spatial distribution of various proton metabolites in the human brain with use of water-suppressed in vivo 1H MR spectroscopic imaging (MRSI) technique MATERIALS AND METHODS: All of water-suppressed in vivo 1H MRSI were performed on 1.5 T whole-body MRI/MRS system using Stimulated Echo Acquisition Method (STEAM) Chemical shift Imaging (CSI) pulse sequence. T1 -weighted MR images were used for CSl Field Of View (FOV; 24 cm). Voxel size of 1.S cm3 was designated from the periphery of the brain which was divided by 1024 x 16 x 16data points. RESULTS: Metabolite images of N-acetylaspartate (NAA), creatine/phosphocreatine (Cr) + choline/phosphocholine (Cho), and complex of gamma-aminobutyric acid (GABA) -I- glutamate (Glu) were obtained on the human brain. CONCLUSION: Our preliminary study suggests that in vivo 1H MRSl could provide the metabolite imaging to compensate for hypermetabolism on Positron Emission Tomography (PET) scans on the basis of the metabolic informations on brain tissues. The unique ability of in vivo 1H MRSI to offer noninvasive informations about tissue biochemistry in disease states will stimulate on clinical research and disease diagnosis.
Biochemistry ; Brain* ; Diagnosis ; gamma-Aminobutyric Acid ; Glutamic Acid ; Humans* ; Magnetic Resonance Imaging ; Positron-Emission Tomography ; Protons

Cholangiocytes, the lining epithelial cells in bile ducts, are an important subset of liver cells. They are activated by endogenous and exogenous stimuli and are involved in the modification of bile volume and composition. They are also involved in damaging and repairing the liver. Cholangiocytes have many functions including bile production. They are also involved in transport processes that regulate the volume and composition of bile. Cholangiocytes undergo proliferation and cell death under a variety of conditions. Cholangiocytes have functional and morphological heterogenecity. The immunobiology of cholangiocytes is important, particularly for understanding biliary disease. Secretion of different proinflammatory mediators, cytokines, and chemokines suggests the major role that cholangiocytes play in inflammatory reactions. Furthermore, paracrine secretion of growth factors and peptides mediates extensive cross-talk with other liver cells, including hepatocytes, stellate cells, stem cells, subepithelial myofibroblasts, endothelial cells, and inflammatory cells. Cholangiopathy refers to a category of chronic liver diseases whose primary disease target is the cholangiocyte. Cholangiopathy usually results in end-stage liver disease requiring liver transplant. We summarize the biology of cholangiocytes and redefine the concept of cholangiopathy. We also discuss the recent progress that has been made in understanding the pathogenesis of cholangiopathy and how such progress has influenced therapy.
Bile ; Bile Ducts ; Biology* ; Cell Death ; Chemokines ; Cytokines ; Endothelial Cells ; Epithelial Cells ; Hepatocytes ; Intercellular Signaling Peptides and Proteins ; Liver ; Liver Diseases ; Myofibroblasts ; Peptides ; Stem Cells

No abstract available.
Humans ; Hypertension* ; Kidney Failure, Chronic* ; Renal Insufficiency*

No abstract available.
Humans ; Hypertension* ; Kidney Failure, Chronic* ; Renal Insufficiency*

Purpose: Joint label fusion (JLF) is a popular multi-atlas-based segmentation algorithm, which compensates for dependent errors that may exist between atlases.However, in order to get good segmentation results, it is very important to set the several free parameters of the algorithm to optimal values. In this study, we first investigate the feasibility of a JLF algorithm for prostate segmentation in MR images, and then suggest the optimal set of parameters for the automatic prostate segmentation by validating the results of each parameter combination. Materials and Methods: We acquired T2-weighted prostate MR images from 20 normal heathy volunteers and did a series of cross validations for every set of parameters of JLF. In each case, the atlases were rigidly registered for the target image. Then, we calculated their voting weights for label fusion from each combination of JLF’s parameters (rpxy , rpz , rsxy , rsz , β). We evaluated the segmentation performances by five validation metrics of the Prostate MR Image Segmentation challenge. Results: As the number of voxels participating in the voting weight calculation and the number of referenced atlases is increased, the overall segmentation performance is gradually improved. The JLF algorithm showed the best results for dice similarity coefficient, 0.8495 ± 0.0392; relative volume difference, 15.2353 ± 17.2350; absolute relative volume difference, 18.8710 ± 13.1546; 95% Hausdorff distance, 7.2366 ± 1.8502; and average boundary distance, 2.2107 ± 0.4972; in parameters of rpxy = 10, rpz = 1, rsxy = 3, rsz = 1, and β = 3. Conclusion The evaluated results showed the feasibility of the JLF algorithm for automatic segmentation of prostate MRI. This empirical analysis of segmentation results by label fusion allows for the appropriate setting of parameters.

PURPOSE: This study evaluated the efficacy for preventing venous thromboembolism (VTE) and adverse effects of low-molecular-weight heparin (LMWH) in order to launch a prospective clinical trial in Korea. METHODS: We reviewed the medical records of 108 consecutive patients who underwent gastric cancer surgery. These patients were divided into 2 groups according to the type of thromboprophylaxis: group A, LMWH combined with intermittent pneumatic compression (IPC); group B, IPC alone. The postoperative outcomes of the two groups were compared. RESULTS: Symptomatic VTE was observed in only 1 patient (0.9%) from group B. Postoperative bleeding was more common in group A than in group B (10.9% vs. 7.5%), although the difference was not significant (P = 0.055). Most bleeding episodes were minor and managed conservatively without intervention. Only a high body mass index was associated with a significantly increased risk of postoperative bleeding (odds ratio, 1.45; 95% confidence interval, 1.12-2.43; P = 0.051). CONCLUSION: A 40 mg of enoxaparin sodium is a safe and feasible dose for prevention of VTE. With the results of this study, we are planning a prospective randomized clinical trial to investigate the clinical efficacy of LMWH thromboprophylaxis in gastric cancer patients in Korea.
Body Mass Index ; Enoxaparin ; Hemorrhage ; Heparin* ; Heparin, Low-Molecular-Weight ; Humans ; Korea ; Medical Records ; Prospective Studies ; Sodium ; Stomach Neoplasms* ; Thromboembolism ; Venous Thromboembolism

This erratum is being published to correct the printing error on page 517 of the article. Corrections for Fig. 1 and main text in page 519 are needed. The authors apologize for any inconvenience that this may have caused.

Hydrops fetalis is diagnosed when abnormal fluid collections are manifest in two or more fetal compartments, including abdominal ascites, pleural effusions, pericardial effusions, skin edema, polyhydroamniosis and placental edema. Although fetal hydrops was hystorically most commonly associated with Rh blood group isoimmunization, the availability of Rh immunoglobulin has increased the proportion of fetuses affected due to nonimmune etiologies. We have experienced a case of nonimmune hydrops fetalis at 32 weeks of gestation in a 27-year-old woman and reported that with brief review of related literatures.
Adult ; Ascites ; Edema ; Female ; Fetus ; Humans ; Hydrops Fetalis* ; Immunoglobulins ; Pericardial Effusion ; Pleural Effusion ; Pregnancy ; Skin

PURPOSE: To review MR findings of the posterior fossa hemangioblastomas and to evaluate diagnostic value of MRI correlated with CT and anglographic findings. MATERIALS AND METHODS: The MR findings in twelve patients with surgically proven posterior fossa hemangioblastomas including one case of von Hippel- Lindau disease were retrospectively analyzed and correlated with CT (7 patients) and anglographic findings (9 patients). RESULTS: On MRI, five hemangioblastomas were located in the cerebellar hemisphere and seven in the vermis. The masses appeared to be solid in 3 cases(25%), solid tumors with central cyst in 2 cases(17%), and cyst with mural nodules in 7 cases(58%). Abnormal tumor vessels represented by characteristic signal voids on MRI were observed in 9 cases(75%) and were not seen in 3 cases(25%) with mural nodule below 1.5cm in diameter. On pre-contrast CT, hemangioblastomas appeared poorly marginated slightly hyperdense masses in solid tumors, and hypodense cystic masses in cysts. After contrast enhancement, solid tumors were markedly enhanced, but it was difficult to differentiate hemangioblastomas from other tumors. In nine patients, anglograms demonstrated hypervascular blush corresponding to the solid component of the tumors. CONCLUSION: MRI was superior to CT in evaluating the characteristic of abnormal tumor vessels and mural nodules, delineation of tumor margin and tumor extent. Angiography was useful in the diagnosis of cystic hemangioblastomas which contain small mural nodule (less than 1.5cm in diameter) without definite vascular signal voids on MRI. MRI demonstrated solid or cystic tumor with small mural nodule and abnormal vascular signal voids in the posterior fossa should suggest hemangioblastoma.
Angiography ; Diagnosis ; Hemangioblastoma* ; Humans ; Magnetic Resonance Imaging ; Retrospective Studies ; von Hippel-Lindau Disease

PURPOSE: The purpose is to evaluate the CT or MRI findings to help in the differentiation between benign and malignant meningiomas. MATERIAL AND METHODS: The CT and MRI findings of 8 patients with surgically proven malignant meningioma were reviewed. Four cases of 8 malignant meningiomas and 18 cases of 27 benign lesions were studied with a 1.5T or 0.5T MRI. Radiologic analysis was focused on the heterogeneity of tumor, grade of peritumoral edema, presence of cystic degeneration and calcification, tumoral enhancement pattern, dural enhancement, and tumoral border. RESULT: Histologic types of malignant meningioma were meningotheliomatous (n=4), papillary(n=1), fibroblastic(n=l), angioblastic(n=l), and sarcomatous(n=l). Tumoral Heterogeneity was seen in 8 of 8 malignant lesions(100%) and 8 of 27 benign ones(30%). (p<0.01) Marked peritumoral edema was seen in 8 of 8 malignant lesions(100%) and 2 of 27 benign ones. (7.3%)(p<0.01) Most of malignant lesions(6 of 8 cases, 75%) showed ill defined border. Calcification was not present in malignant lesions in contrast with benign ones (14 of 27 cases, 52%). (p<0.05) No statistical significance was noted in cystic degeneration, dural tail like enhancement or tumoral enhancement pattern between malignant and benign meningiomas. MRI signal intensity of malignant meningiomas was homogeneously or heterogeneously hypointense on T1WI, heterogeneously isointense or hypointense on T2WI and heterogeneous or mixed on Gd-DTPA enhancement study. CONCLUSION: The CT or MRI findings such as heterogeneity, ill defined tumoral border, marked peritumoral edema, and absence of calcification may suggest the possibility of malignancy in meningioma.
Edema ; Gadolinium DTPA ; Humans ; Magnetic Resonance Imaging* ; Meningioma* ; Population Characteristics