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In East Asian waters, concern about giant jellyfish blooms, including Nemopilema nomurai (Cnidaria: Scyphozoa: Rhizostomeae), has increased in recent decades. Based on surveys in 2012 and 2013, as a part of the Chinese Jellyfish 973... more
In East Asian waters, concern about giant jellyfish blooms, including Nemopilema nomurai (Cnidaria: Scyphozoa: Rhizostomeae), has increased in recent decades. Based on surveys in 2012 and 2013, as a part of the Chinese Jellyfish 973 Program, we investigated the life cycle in situ of the planktonic stages of this species in the Yellow Sea and the East China Sea. We found the following results: (1) Offshore of the Changjiang River is one of its principal breeding places, and is the area where the pelagic stages of N. nomurai appear earliest in the YS and ECS. (2) The general distribution pattern of pelagic stages of N. nomurai described previously in the YS and ECS is confirmed from the 2012 and 2013 surveys: From this small area (31.50-33.00°N, 122.00-122.75°E) usually in late May and early June, it expanded into the 31.5-36°N sea area (aggregating in 32-34°N) in June, then continued to expand northward and southward to 30-37°N by August, and then shrank to 34-37°N in October. (3) Th...
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To evaluate whether CT findings suggesting active pulmonary tuberculosis correlate with sputum microbiological studies, and to determine whether CT could predict infectivity. Total 108 patients with active pulmonary tuberculosis were... more
To evaluate whether CT findings suggesting active pulmonary tuberculosis correlate with sputum microbiological studies, and to determine whether CT could predict infectivity. Total 108 patients with active pulmonary tuberculosis were enrolled. We reviewed CT findings and sputum microbiological studies. Then, we analyzed the statistical difference in CT findings between the positive and negative groups of each sputum microbiological study (AFB smear, PCR, and culture). Also, we divided the patients into five groups according to sputum AFB smear grade and analyzed linear trends of CT findings between the five groups. Both frequencies and extents of centrilobular micronodules (63% vs 38%, p=0.011 for frequency; 1.6±1.6 vs 0.6±1.1, p=0.001 for extent), tree-in-bud opacities (63% vs 33%, p=0.002; 1.6±1.6 vs 0.5±0.9, p<0.001, respectively), consolidation (98% vs 81%, p=0.003; 2.7±1.5 vs 1.3±1.1, p<0.001, respectively), and cavitation (86% vs 33%, p<0.001; 1.5±1.2 vs 0.4±0.7, p<...
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To observe changes in pharyngeal pressure during the swallowing process according to postures in normal individuals using high-resolution manometry (HRM). Ten healthy volunteers drank 5 mL of water twice while sitting in a neutral... more
To observe changes in pharyngeal pressure during the swallowing process according to postures in normal individuals using high-resolution manometry (HRM). Ten healthy volunteers drank 5 mL of water twice while sitting in a neutral posture. Thereafter, they drank the same amount of water twice in the head rotation and head tilting postures. The pressure and time during the deglutition process for each posture were measured with HRM. The data obtained for these two postures were compared with those obtained from the neutral posture. The maximum pressure, area, rise time, and duration in velopharynx (VP) and tongue base (TB) were not affected by changes in posture. In comparison, the maximum pressure and the pre-upper esophageal sphincter (UES) maximum pressure of the lower pharynx in the counter-catheter head rotation posture were lower than those in the neutral posture. The lower pharynx pressure in the catheter head tilting posture was higher than that in the counter-catheter head tilting. The changes in the VP peak and epiglottis, VP and TB peaks, and the VP onset and post-UES time intervals were significant in head tilting and head rotation toward the catheter postures, as compared with neutral posture. The pharyngeal pressure and time parameter analysis using HRM determined the availability of head rotation as a compensatory technique for safe swallowing. Tilting the head smoothes the progress of food by increasing the pressure in the pharynx.
ABSTRACT In recent decades, massive outbreaks of the giant jellyfish, Nemopilema nomurai have been appearing frequently in coastal seas of China. In the life cycle of N. nomurai, asexual reproduction by its benthic polyps may largely... more
ABSTRACT In recent decades, massive outbreaks of the giant jellyfish, Nemopilema nomurai have been appearing frequently in coastal seas of China. In the life cycle of N. nomurai, asexual reproduction by its benthic polyps may largely determine the jellyfish population size, and it was thought that asexual reproduction leading to medusae might be affected by differences in the duration at low winter temperature on different parts of the coast. To test this hypothesis, polyps were first stored at low temperature for two different durations, 5°C for either 40 or 117 days. They were then maintained at seven temperatures, (maintained at 5°C, and separately elevated to 10, 13, 16, 19, 22, 27°C) reached by raising the temperature 1°C every 2 days from 5°C, as well as a control temperature: 5°C. Polyps were fed with three frequencies (once per 5 days, once per 10 days, and unfed, prey concentration, 0.1 mgC l−1, being supplied once). The percentages of polyps strobilating, strobilation duration, ephyra and podocyst production were recorded. The results showed that longer duration at low temperature accelerated strobila formation at warmer temperature, as well as significantly enhancing podocyst production, but not for the strobilation percentage or ephyra production. Temperature had a marked influence on strobilation percentage, as well as on ephyra and podocyst production. The optimum temperature for strobilation by N. nomurai polyps ranged from 10 to 13°C. The maximum numbers of ephyrae appeared after polyps had been stored at longer low temperature then warmed to 10°C and fed once per 5 days, while the maximum production of podocysts occurred in polyps warmed to 27°C and fed once per 5 days. We conclude that longer duration at low temperature in winter, a continuous 10-13°C period in spring, and increasing food supply all accelerate the strobila formation, increase jellyfish production and are tend to increase blooms of N. nomurai medusae.
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We present the case of a surgically confirmed, invasive, cystic hypersecretory ductal carcinoma (CHDC) of the breast in a 43-year-old woman. The initial sonography showed a complex cyst, which required a core biopsy; however, the... more
We present the case of a surgically confirmed, invasive, cystic hypersecretory ductal carcinoma (CHDC) of the breast in a 43-year-old woman. The initial sonography showed a complex cyst, which required a core biopsy; however, the diagnosis was delayed as the patient refused to undergo the biopsy and the cyst decreased in size, as seen on follow-up sonography. Excision biopsy was performed, and invasive CHDC was diagnosed after regrowth of the cystic lesion. Meticulous sonographic evaluation of a cystic breast mass is always important, and pathology confirmation must be considered if the lesion shows features suspicious for malignancy, as a CHDC could be the cause of a cystic breast mass.
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In vivo tracking of the transplanted stem cells is important in pre-clinical research of stem cell therapy for myocardial infarction. We examined the feasibility of adenovirus-mediated sodium iodide symporter (NIS) gene to cell tracking... more
In vivo tracking of the transplanted stem cells is important in pre-clinical research of stem cell therapy for myocardial infarction. We examined the feasibility of adenovirus-mediated sodium iodide symporter (NIS) gene to cell tracking imaging of transplanted stem cells in a canine infarcted myocardium by clinical single photon emission computed tomography (SPECT). Beagle dogs were injected intramyocardially with NIS-expressing adenovirus-transfected canine stem cells (Ad-hNIS-canine ADSCs) a week after myocardial infarction (MI) development. (99m)Tc-methoxyisobutylisonitrile ((99m)Tc-MIBI) and (99m)Tc-pertechnetate ((99m)TcO4(-)) SPECT imaging were performed for assessment of infarcted myocardium and viable stem cell tracking. Transthoracic echocardiography was performed to monitor any functional cardiac changes. Left ventricular ejection fraction (LVEF) was decreased after LAD ligation. There was no significant difference in EF between the groups with the stem cell or saline inje...
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ABSTRACT
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To evaluate the utility of three-dimensional (3D) reconstruction when planning the surgical treatment of nasal bone fractures. The axial scan of high-resolution facial bone CT was reconstructed in 3D using the program V-works 4.0... more
To evaluate the utility of three-dimensional (3D) reconstruction when planning the surgical treatment of nasal bone fractures. The axial scan of high-resolution facial bone CT was reconstructed in 3D using the program V-works 4.0 (CyberMed, Seoul, Korea) with a volume and surface rendering technique. For detailed stereoscopic examination of the nasal valve area, an air-bone view with the volume rendering technique was obtained using thresholds for air, cartilage, and bone. In most nasal bone fractures, 2D and 3D CT had similar detection rates. However, to determine the fracture angle and dimpled area, and identify multiple fractures, surgeons can get better information to help with the reduction of the fractured bone from 3D reconstruction images. Additionally, with a septal deformity, this view helps in deciding on the need for septal surgery during nasal reduction. The air view of the nasal passage provides clues to obstruction of the nasal cavity. We could identify the contour an...
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To identify risk factors for nonalcoholic steatohepatitis following pancreaticoduodenectomy, with a focus on factors related to pancreatic secretions. The medical records of 228 patients who had a pancreaticoduodenectomy over a 16-mo... more
To identify risk factors for nonalcoholic steatohepatitis following pancreaticoduodenectomy, with a focus on factors related to pancreatic secretions. The medical records of 228 patients who had a pancreaticoduodenectomy over a 16-mo period were reviewed retrospectively. The 193 patients who did not have fatty liver disease preoperatively were included in the final analysis. Hepatic steatosis was diagnosed using the differences between splenic and hepatic attenuation and liver-to-spleen attenuation as measured by non-enhanced computed tomography. Fifteen patients (7.8%) who showed postoperative hepatic fatty changes were assigned to Group A, and the remaining patients were assigned to Group B. Patient demographics, preoperative laboratory findings (including levels of C-peptide, glucagon, insulin and glucose tolerance test results), operation types, and final pathological findings did not differ significantly between the two groups; however, the frequency of pancreatic fistula (P = ...
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The aim of this study was to determine the computed tomography (CT)-pathological correlation of malignant solitary fibrous tumors of the pleura (MSFP) and to compare these findings with CT findings of benign solitary fibrous tumors of the... more
The aim of this study was to determine the computed tomography (CT)-pathological correlation of malignant solitary fibrous tumors of the pleura (MSFP) and to compare these findings with CT findings of benign solitary fibrous tumors of the pleura (BSFTP). We retrospectively identified the clinical, CT, and pathological findings in seven cases of MSFP. There was a CT-pathological correlation for the MSFPs. Additionally, 12 cases of BSFTP from case files were compared with the clinical and CT features of the MSFPs. On CT, the MSFP appeared as a heterogeneously enhancing mass >10 cm (100%). Pleural metastasis (57.1%) and lung metastasis (14.3%) were associated. In the CT-pathological correlation, the enhancing area was mixed cellular and collagenous tissue with hypercellularity, mitosis, and pleomorphism. Hemorrhage, necrosis, cystic, or myxoid degeneration produced areas of intratumoral low attenuation. MSFPs showed a higher incidence of intratumoral low-attenuation areas (P = 0.034...
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Gastric complications following unintentional foreign body ingestion are extremely rare. Here, we report the case of a 59-year-old healthy woman who presented with nonspecific abdominal pain and an apparent gastric submucosal tumor that... more
Gastric complications following unintentional foreign body ingestion are extremely rare. Here, we report the case of a 59-year-old healthy woman who presented with nonspecific abdominal pain and an apparent gastric submucosal tumor that was incidentally detected by gastrofiberscopy. The patient underwent laparoscopic surgery, which revealed an intact gastric wall with no tumor invasion, deformity, or evidence of a gastric submucosal lesion. However, an impacted fish bone was found.
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It has not yet been determined whether chronic exposure to relatively low doses of pioglitazone increases risk of bladder cancer. We aimed to assess the risk of bladder cancer associated with pioglitazone in Korean patients. This was a... more
It has not yet been determined whether chronic exposure to relatively low doses of pioglitazone increases risk of bladder cancer. We aimed to assess the risk of bladder cancer associated with pioglitazone in Korean patients. This was a retrospective cohort study of diabetic patients who had ≥ 2 clinic visits between November 2005 and June 2011 at one of four tertiary referral hospitals in Korea. A prevalent case-control analysis nested within the cohort was conducted to further adjust confounders. A total of 101,953 control patients and 11,240 pioglitazone-treated patients were included, in which there were 237 and 30 cases of incidental bladder cancer (64.9 and 54.9 per 100,000 person-years; age, sex-adjusted HR 1.135, 95% confidence interval [CI] 0.769-1.677), respectively. In the prevalent case-control analysis nested within the cohort, use of pioglitazone for a duration of > 6 months, but not ever use of pioglitazone, was associated with an increased rate of bladder cancer as...
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Daya Bay is a large bay along the southern coast of China. The composition, abundance, community structure and diversity of phytoplankton in Daya Bay were investigated to assess its status in different seasons in 2002, and a total of 48... more
Daya Bay is a large bay along the southern coast of China. The composition, abundance, community structure and diversity of phytoplankton in Daya Bay were investigated to assess its status in different seasons in 2002, and a total of 48 genera and 114 species of phytoplankton were identified. The cell abundance of phytoplankton varied from 5.79 × 104 cells/m3 to
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A non-invasive method to characterize human mesenchymal stromal cells during adipogenic differentiation was developed for the first time. Seven fatty acid methyl esters (FAMEs), including methyl laurate, methyl myristate, methyl... more
A non-invasive method to characterize human mesenchymal stromal cells during adipogenic differentiation was developed for the first time. Seven fatty acid methyl esters (FAMEs), including methyl laurate, methyl myristate, methyl palmitate, methyl linoleate, methyl oleate, methyl elaidate and methyl stearate, were used for characterizing adipogenic differentiation using headspace solid-phase microextraction (HS-SPME) which is a very simple and non-invasive method for the extraction of volatile compounds. Glassware was used for culturing mesenchymal stromal cells rather than the common plasticware to minimize contamination by volatile impurities. The optimal SPME fiber was selected by comparing diverse fibers containing two pure liquid polymers (PDMS and PA) and two porous solids (PDMS/DVB and CAR/PDMS). Using optimized procedures, we discovered that seven FAMEs were only detected in adipogenic differentiated mesenchymal stromal cells and not in the mesenchymal stromal cells before di...
The aims of this national survey were to determine the views of Korean people regarding the specialty of anesthesiology and the role of anesthesiologists and to consider the ways in which individual anesthesiologists and the Korean... more
The aims of this national survey were to determine the views of Korean people regarding the specialty of anesthesiology and the role of anesthesiologists and to consider the ways in which individual anesthesiologists and the Korean Society of Anesthesiologists inform the public. This off-line national survey was conducted by a professional research organization to obtain exact and reliable data. The questionnaire included structured questions to identify perceptions of the specialty of anesthesiology and the role of anesthesiologists inside and outside the operating room, people's desire for explanation of anesthesia by anesthesiologists, and their opinion about the best way to raise awareness about anesthesia and anesthesiologists. Of the respondents, 25.2% did not know that anesthesiologists are in charge of anesthesia during surgery. Furthermore, even respondents who knew that had very little knowledge of anesthesiologists' actual roles inside and outside the operating ro...
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Carpal tunnel release is required to treat patients with severe carpal tunnel syndrome. The regional anesthesia of the upper limb by brachial plexus block (BPB) may be a good alternative to general anesthesia for carpal tunnel release... more
Carpal tunnel release is required to treat patients with severe carpal tunnel syndrome. The regional anesthesia of the upper limb by brachial plexus block (BPB) may be a good alternative to general anesthesia for carpal tunnel release surgery, because it results in less complications. However, the regional anesthesia still has various side effects, such as hematoma, infection, and peripheral neuropathy. We hereby report a rare case of median nerve injury caused by BPB for carpal tunnel release.
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Attempt to identify the beneficial effects associated with surgical procedures on survival outcome of patients with recurrent cholangiocarcinoma. 921 patients diagnosed with cholangiocarcinoma underwent surgical resection with curative... more
Attempt to identify the beneficial effects associated with surgical procedures on survival outcome of patients with recurrent cholangiocarcinoma. 921 patients diagnosed with cholangiocarcinoma underwent surgical resection with curative intent in a single institute during the last 15 years. Patients with recurrent disease were divided into two groups according to whether surgical procedures were performed for the treatment of recurrence. Clinicopathologic variables, ranges of survival based on sites of recurrence, and types of treatment were analyzed retrospectively. The median follow-up period was 21.8 months and 316 (34.3%) patients had recurrence. 27 (group A) patients with recurrent disease were treated surgically and 289 patients (group B) were not treated. Liver resection, metastasectomy, pancreaticoduodenectomy, partial pancreatectomy, and regional lymph node dissection were performed on the patients in group A. The overall survival rate was statistically higher in group A (P = 0.001). Among the surgical procedures, resection of locoregional recurrences (except liver) in abdominal cavity (4.0 to 101.8 months vs. 0.6 to 71.6 months) and metastasectomy of abdominal or chest wall (3.5 to 18.9 months vs. 1.9 to 2.2 months) showed remarkable differences with respect to the range of survival. Better survival outcomes can be expected by performing surgical resection of locoregional recurrences (except liver) in abdominal cavity and abdominal or chest wall metastatic lesions in recurrent cholangiocarcinoma.
Age groups of Antarctic krill (Euphausia superba Dana) in the Prydz Bay region were studied by distribution mixture analysis based on length/frequency data collected by R/VJidi during the 1989/1990 and 1990/1991 austral summer. Five age... more
Age groups of Antarctic krill (Euphausia superba Dana) in the Prydz Bay region were studied by distribution mixture analysis based on length/frequency data collected by R/VJidi during the 1989/1990 and 1990/1991 austral summer. Five age groups were determined, i.e. 1+, 2+, 3+, 4+, and 5+, or six age groups in all, if the 0+ larvae were included. The mean body
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This study compared the glycemic effectiveness of three metformin-based dual therapies according to baseline hemoglobin A1c (HbA1c) to evaluate the appropriateness of the guideline enforced by the National Health Insurance Corporation of... more
This study compared the glycemic effectiveness of three metformin-based dual therapies according to baseline hemoglobin A1c (HbA1c) to evaluate the appropriateness of the guideline enforced by the National Health Insurance Corporation of Korea for initial medication of type 2 diabetes (T2D). This prospective observational study was conducted across 24 weeks for drug-naïve Korean T2D patients with HbA1c greater than 7.5%. Subjects were first divided into three groups based on the agent combined with metformin (group 1, gliclazide-modified release or glimepiride; group 2, pioglitazone; group 3, sitagliptin). Subjects were also classified into three categories according to baseline HbA1c (category I, 7.5%≤HbA1c<9.0%; category II, 9.0%≤HbA1c<11.0%; category III, 11.0%≤HbA1c). Among 116 subjects, 99 subjects completed the study, with 88 subjects maintaining the initial medication. While each of the metformin-based dual therapies showed a significant decrease in HbA1c (group 1, 8.9%...
We assessed the tolerability, effectiveness and predictive parameters for the therapeutic usefulness of exenatide in obese Korean participants with type 2 diabetes. We also evaluated the characteristics of participants who respond... more
We assessed the tolerability, effectiveness and predictive parameters for the therapeutic usefulness of exenatide in obese Korean participants with type 2 diabetes. We also evaluated the characteristics of participants who respond adequately to glucagon-like peptide-1 (GLP-1) analog therapy in terms of glycated hemoglobin (HbA1c) level reductions and weight loss. This prospective, observational, single-arm (exenatide b.i.d. in combination with both metformin and sulphonylurea), open-label study of GLP-1 analog treatment with close monitoring of metabolic parameters and weight changes was carried out for up to 22 weeks. Of the 110 enrolled obese participants, 37 participants dropped out during the 22-week treatment period. A total of 73 participants completed the study (median age 55.0 years, interquartile range 44.0-65.0). The median duration of diabetes was 8.0 years (interquartile range 3.5-12.5) with a mean HbA1c value of 7.6% (interquartile range 7.00-8.55). The median body mass...
The purpose of this study was to investigate the efficacy of cartilage regeneration when using a mixture of transforming growth factor-beta1 (TGF-beta1)-producing human chondrocytes (hChon-TGF-beta1) and primary human chondrocytes (hChon)... more
The purpose of this study was to investigate the efficacy of cartilage regeneration when using a mixture of transforming growth factor-beta1 (TGF-beta1)-producing human chondrocytes (hChon-TGF-beta1) and primary human chondrocytes (hChon) (&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;quot;mixed cells&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;quot;), compared with either hChon-TGF-beta1 or hChon cells alone. Specifically, mixed cells or hChon cells were first injected intradermally into the backs of immune-deficient nude mice to test the feasibility of cartilage formation in vivo. Both the mixed cells and the hChon-TGF-beta1 cells alone induced cartilage formation in nude mice, whereas hChon cells alone did not. To further test the efficacy of the cells in generating cartilage, an artificially induced partial thickness defect of the femoral condyle of a rabbit knee joint was loaded with hChon-TGF-beta1 cells with or without mixing additional untransduced hChon cells, and hyaline cartilage regeneration was observed at 4 or 6 weeks. The efficiency of complete filling of the defect and the quality of tissue generated after implanting were evaluated on the basis of a histological grading system modified from O&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;#39;Driscoll et al. (J. Bone Joint Surg. 70A, 595, 1988). Significantly, mixed cells (14.2 +/- 0.9) produced significantly better results than hChon-TGF-beta1 (9.0 +/- 1.7) or hChon (8.0 +/- 1.8) cells alone. Histological and immunohistochemical staining of the newly repaired tissues produced after treatment with either mixed cells or hChon-TGF-beta1 cells alone showed hyaline cartilage- like characteristics. These results suggest that the implantation of mixed cells may be a clinically efficient method of regenerating hyaline articular cartilage.
