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1.  Korean Red Ginseng Induced Cardioprotection against Myocardial Ischemia in Guinea Pig 
This study was designed to evaluate the protective effect of Korean red ginseng (KRG) against ischemia/reperfusion (I/R) injury in isolated guinea pig heart. KRG has been shown to possess various ginsenosides, which are the major components of Panax ginseng. These components are known naturally occurring compounds with beneficial effects and free radical scavenging activity. The heart was induced to ischemia for 60 min, followed by 120 min reperfusion. The hearts were randomly allocated into five groups (n=8 for each group): normal control (N/C), KRG control, I/R control, 250 mg/kg KRG group and 500 mg/kg KRG group. KRG significantly increased hemodynamics parameters such as aortic flow, coronary flow and cardiac output. Moreover, KRG significantly increased left ventricular systolic pressure (LVSP), the maximal rate of contraction (+dP/dtmax) and maximal rate of relaxation (-dP/dtmax). Also, treatment of KRG ameliorated electrocardiographic index such as the QRS, QT and RR intervals. Moreover, KRG significantly suppressed the lactate dehydrogenase, creatine kinase-MB fraction and cardiac troponin I and ameliorated the oxidative stress markers such as malondialdehyde and glutathione. KRG was standardized through ultra performance liquid chromatograph analysis for its major ginsenosides. Taken together, KRG has been shown to prevent cardiac injury by normalizing the biochemical and oxidative stress.
PMCID: PMC3741484  PMID: 23946687
Antioxidant; Cardioprotection; Hemodynamics; Ischemia and reperfusion injury; Korean red ginseng
2.  Altered heart rate dynamics associated with antipsychotic-induced subjective restlessness in patients with schizophrenia 
Antipsychotic-induced subjective inner restlessness is one of the common and distressing adverse effects associated with antipsychotics; however, its underlying neurobiological basis is not well understood. We examined the relationship between antipsychotic-induced subjective inner restlessness and autonomic neurocardiac function.
Twenty-two schizophrenia patients with antipsychotic-induced subjective restlessness, 28 schizophrenia patients without antipsychotic-induced subjective restlessness, and 28 matched healthy control subjects were evaluated. Assessments of the linear and nonlinear complexity measures of heart rate dynamics were performed. Multivariate analysis of variance and correlation analysis were conducted.
The mean interbeat (RR) interval value was significantly higher in control subjects than in patients with and without antipsychotic-induced subjective restlessness (P < 0.05). The low frequency/high frequency ratio was significantly higher in patients with antipsychotic-induced subjective restlessness than in control subjects and in patients without antipsychotic-induced subjective restlessness (P < 0.05), while the approximate entropy value was significantly lower in patients with antipsychotic-induced subjective restlessness than in control subjects and in patients without antipsychotic-induced subjective restlessness (P < 0.05). Correlation analyses controlling for psychotic symptom severity showed that the degree of antipsychotic-induced restlessness had a significant negative correlation with the value of approximate entropy (P < 0.05).
The results indicate that antipsychotic-induced subjective restlessness is associated with altered heart rate dynamics parameters, particularly the nonlinear complexity measure, suggesting that it might adversely affect autonomic neurocardiac integrity. Further prospective research is necessary to elucidate the precise interrelationships and causality.
PMCID: PMC3753732  PMID: 23986638
antipsychotics; subjective restlessness; heart rate dynamics
3.  HIV Transmission by Stage of Infection and Pattern of Sexual Partnerships 
Epidemiology (Cambridge, Mass.)  2010;21(5):676-684.
Most model analyses examining the role of primary HIV infection in the HIV epidemic ignore the fact that HIV is often transmitted through long-term, concurrent sexual partnerships. We sought to understand how duration and concurrency of sexual partnerships affect the role of transmissions during primary HIV infection.
We constructed a stochastic individual-based model of HIV transmission in a homogeneous population where partnerships form and dissolve. Using observed contagiousness by stage of HIV infection, the fraction of transmissions during primary HIV infection at equilibrium was examined across varying partnership durations and concurrencies.
The fraction of transmissions during primary HIV infection has a U-shaped relationship with partnership duration. The fraction drops with increasing partnership duration for partnerships with shorter average duration but rises for partnerships with longer average duration. Partnership concurrency modifies this relationship. The fraction of transmissions during primary HIV infection increases with increasing partnership concurrency for partnerships with shorter average duration, but decreases for partnerships with longer average duration.
Partnership patterns strongly influence the transmission of HIV and do so differentially by stage of infection. Dynamic partnerships need to be taken into account to make a robust inference on the role of different stages of HIV infection.
PMCID: PMC3018805  PMID: 20571409
4.  A comparison of Bonfils intubation fiberscopy and fiberoptic bronchoscopy in difficult airways assisted with direct laryngoscopy 
Korean Journal of Anesthesiology  2010;58(3):249-255.
To evaluate the usefulness of Bonfils intubation fiberscope assisted by direct laryngoscopy (BIF-DL) and flexible fiberoptic bronchoscope assisted by direct laryngoscopy (FOB-DL) using video recording in cases of unanticipated difficult intubation with respect to the time required to visualize the vocal cords and place the endotracheal tube. We compared two fiberscopes in patients with authentic difficult airways.
In this randomized, controlled clinical trial, 40 patients (grade 3 according to grades of difficulty in laryngoscopy), scheduled for surgery under general anesthesia were randomly allocated to BIF-DL group or FOB-DL group. Number of attempts, time required for visualization of the vocal cord (T1) and placement of the endotracheal tube (T2) from insertion of instrument during the last successful attempt, and duration of scope manipulation during all attempts (Ttotal) were recorded. If intubation failed with one method, the other method was tried; these cases were then excluded. The incidence of sore throat and hoarseness was assessed.
T1, T2, and Ttotal were significantly shorter in BIF-DL group (T1: 21.9 ± 8.2 sec vs. 80.4 ± 29.9 sec, P < 0.001, Ttotal: 77.9 ± 41.2 sec vs. 145.5 ± 83.9 sec, P = 0.003). In two cases, it was impossible to intubate with BIF-DL, but the procedure was subsequently successful using fibreoptic bronchoscope.
Intubation of difficult airways can be performed more rapidly with BIF-DL, but sometimes it may not be possible to intubate with the scope.
PMCID: PMC2872830  PMID: 20498773
Bronchoscopes; Fiberoptics; Intubation; Laryngoscopy; Video recording
5.  Effects of ethanol on insulin-like growth factor-I system in primary cultured rat hepatocytes: Implications of JNK1/2 and alcoholdehydrogenase 
AIM: To evaluate the effects of ethanol on the insulin-like growth factor-I (IGF-I) system involved in c-Jun N-terminal kinase (JNK1/2) and alcoholdehydrogenase (ADH) activity in primary cultured rat hepatocytes.
METHODS: Hepatocytes isolated from male Sprague-Dawley rats were incubated with various concentrations of ethanol for different durations of time. The cells were pretreated with SP600125 (10 μmol/L) and 4-MP (200 μmol/L), and then treated with ethanol (200 mmol/L). We then measured IGF-Isecretion, IGF-I mRNA expression, cell viability and JNK1/2 activity by radioimmunoassay, RT-PCR, MTT assay and Western blot, respectively (n = 6).
RESULTS: Ethanol induced the activity of phospho (p)-JNK1/2, reaching a maximum at 60 min and then decreasing at 180 min. The effects of ethanol on the IGF-I system were increased at 60 min (secretion: 7.11 ± 0.59 ng/mg protein vs 4.91 ± 0.51 ng/mg, mRNA expression: 150.2% ± 10.2% vs 101.5% ± 11.3%, P = 0.045) and then decreased at 180 min (secretion: 3.89 ± 0.25 ng/mg vs 5.4 ± 0.54 ng/mg protein; mRNA expression: 41.5% ± 10.4% vs 84.7% ± 12.1%, P = 0.04), however cell viability was decreased in a dose- and time-dependent manner. SP600125 blocked the ethanol-induced changes (at 60 min). Additionally, 4-methylpyrazole prevented the ethanol-induced decreases in the IGF-I system, cell viability and p-JNK1/2 activity (at 180 min).
CONCLUSION: This study suggests that ethanol-induced p-JNK1/2 activation is associated with the IGF-I system and cell viability in hepatocytes. Furthermore, alcohol dehydrogenase is involved in the relationship between ethanol-induced inactivation of p-JNK1/2 and the changes of the IGF-I system and cell viability.
PMCID: PMC2731183  PMID: 18666320
Insulin-like growth factor-I; Insulin-like growth factor-I receptor; C-Jun N-terminal kinase; Hepatocyte; Ethanol
6.  Electrolyte-free Amperometric Immunosensor using a Dendritic Nanotip† 
RSC advances  2013;3(13):4281-4287.
Electric detection using a nanocomponent may lead to platforms for rapid and simple biosensing. Sensors composed of nanotips or nanodots have been described for highly sensitive amperometry enabled by confined geometry. However, both fabrication and use of nanostructured sensors remain challenging. This paper describes a dendritic nanotip used as an amperometric biosensor for highly sensitive detection of target bacteria. A dendritic nanotip is structured by Si nanowires coated with single-walled carbon nanotubes (SWCNTs) for generation of a high electric field. For reliable measurement using the dendritic structure, Si nanowires were uniformly fabricated by ultraviolet (UV) lithography and etching. The dendritic structure effectively increased the electric current density near the terminal end of the nanotip according to numerical computation. The electrical characteristics of a dendritic nanotip with additional protein layers was studied by cyclic voltammetry and I–V measurement in deionized (DI) water. When the target bacteria dielectrophoretically captured onto a nanotip were bound with fluorescence antibodies, the electric current through DI water decreased. Measurement results were consistent with fluorescence- and electron microscopy. The sensitivity of the amperometry was 10 cfu/sample volume (103 cfu/mL), which was equivalent to the more laborious fluorescence measurement method. The simple configuration of a dendritic nanotip can potentially offer an electrolyte-free detection platform for sensitive and rapid biosensors.
PMCID: PMC3622275  PMID: 23585927
7.  Semi-Automated, Occupationally Safe Immunofluorescence Microtip Sensor for Rapid Detection of Mycobacterium Cells in Sputum 
PLoS ONE  2014;9(1):e86018.
An occupationally safe (biosafe) sputum liquefaction protocol was developed for use with a semi-automated antibody-based microtip immunofluorescence sensor. The protocol effectively liquefied sputum and inactivated microorganisms including Mycobacterium tuberculosis, while preserving the antibody-binding activity of Mycobacterium cell surface antigens. Sputum was treated with a synergistic chemical-thermal protocol that included moderate concentrations of NaOH and detergent at 60°C for 5 to 10 min. Samples spiked with M. tuberculosis complex cells showed approximately 106-fold inactivation of the pathogen after treatment. Antibody binding was retained post-treatment, as determined by analysis with a microtip immunosensor. The sensor correctly distinguished between Mycobacterium species and other cell types naturally present in biosafe-treated sputum, with a detection limit of 100 CFU/mL for M. tuberculosis, in a 30-minute sample-to-result process. The microtip device was also semi-automated and shown to be compatible with low-cost, LED-powered fluorescence microscopy. The device and biosafe sputum liquefaction method opens the door to rapid detection of tuberculosis in settings with limited laboratory infrastructure.
PMCID: PMC3899086  PMID: 24465845
8.  Whole pelvic intensity-modulated radiotherapy for high-risk prostate cancer: a preliminary report 
Radiation Oncology Journal  2013;31(4):199-205.
To assess the clinical efficacy and toxicity of whole pelvic intensity-modulated radiotherapy (WP-IMRT) for high-risk prostate cancer.
Materials and Methods
Patients with high-risk prostate cancer treated between 2008 and 2013 were reviewed. The study included patients who had undergone WP-IMRT with image guidance using electronic portal imaging devices and/or cone-beam computed tomography. The endorectal balloon was used in 93% of patients. Patients received either 46 Gy to the whole pelvis plus a boost of up to 76 Gy to the prostate in 2 Gy daily fractions, or 44 Gy to the whole pelvis plus a boost of up to 72.6 Gy to the prostate in 2.2 Gy fractions.
The study cohort included 70 patients, of whom 55 (78%) had a Gleason score of 8 to 10 and 50 (71%) had a prostate-specific antigen level > 20 ng/mL. The androgen deprivation therapy was combined in 62 patients. The biochemical failure-free survival rate was 86.7% at 2 years. Acute any grade gastrointestinal (GI) and genitourinary (GU) toxicity rates were 47% and 73%, respectively. The actuarial rate of late grade 2 or worse toxicity at 2 years was 12.9% for GI, and 5.7% for GU with no late grade 4 toxicity.
WP-IMRT was well tolerated with no severe acute or late toxicities, resulting in at least similar biochemical control to that of the historic control group with a small field. The long-term efficacy and toxicity will be assessed in the future, and a prospective randomized trial is needed to verify these findings.
PMCID: PMC3912233  PMID: 24501707
Prostate neoplasms; Intensity-modulated radiotherapy; Complications
9.  Cardioprotective potential of Korean Red Ginseng extract on isoproterenol-induced cardiac injury in rats 
Journal of Ginseng Research  2013;37(3):273-282.
The present study was designed to investigate the cardioprotective effects of Korean Red Ginseng extract (KRG) on isoproterenol (ISO)-induced cardiac injury in rats, particularly in regards to electrocardiographic changes, hemodynamics, cardiac function, serum cardiac enzymes, components of the myocardial antioxidant defense system, as well as inflammatory markers and histopathological changes in heart tissue. ISO (150 mg/kg, subcutaneous, two doses administered at 24-hour intervals) treatment induced significant decreases in P waves and QRS complexes (p<0.01), as well as a significant increase in ST segments. Moreover, ISO-treated rats exhibited decreases in left-ventricular systolic pressure, maximal rate of developed left ventricular pressure (+dP/dtmax) and minimal rate of developed left ventricular pressure (−dP/dtmax), in addition to significant increases in lactate dehydrogenase, aspartate transaminase, alanine transaminase and creatine kinase activity. Heart rate, however, was not significantly altered. And the activities of superoxide dismutase, catalase and glutathione peroxidase were decreased, whereas the activity of malondialdehyde was increased in the ISO-treated group. ISO-treated group also showed increased caspase-3 level, release of inflammatory markers and neutrophil infiltration in heart tissue. KRG pretreatment (250 and 500 mg/kg, respectively) significantly ameliorated almost all of the parameters of heart failure and myocardial injury induced by ISO. The protective effect of KRG on ISO-induced cardiac injury was further confirmed by histopathological study. In this regard, ISO treatment induced fewer morphological changes in rats pretreated with 250 or 500 mg/kg of KRG. Compared with the control group, all indexes in rats administered KRG (500 mg/kg) alone were unaltered (p>0.05). Our results suggest that KRG significantly protects against cardiac injury and ISO-induced cardiac infarction by bolstering antioxidant action in myocardial tissue.
PMCID: PMC3818953  PMID: 24198652
Panax ginseng; Isoproterenol; Cardiac ischemia; Hemodynamics; Myocardial preservation
10.  Ginsenoside-Re ameliorates ischemia and reperfusion injury in the heart: a hemodynamics approach 
Journal of Ginseng Research  2013;37(3):283-292.
Ginsenosides are divided into two groups based on the types of the panaxadiol group (e.g., ginsenoside-Rb1 and -Rc) and the panaxatriol group (e.g., ginsenoside-Rg1 and -Re). Among them, ginsenoside-Re (G-Re) is one of the compounds with the highest content in Panax ginseng and is responsible for pharmacological effects. However, it is not yet well reported if G-Re increases the hemodynamics functions on ischemia (30 min)/reperfusion (120 min) (I/R) induction. Therefore, in the present study, we investigated whether treatment of G-Re facilitated the recovery of hemodynamic parameters (heart rate, perfusion pressure, aortic flow, coronary flow, and cardiac output) and left ventricular developed pressure (±dp/dtmax). This research is designed to study the effects of G-Re by studying electrocardiographic changes such as QRS interval, QT interval and R-R interval, and inflammatory marker such as tissue necrosis factor-α (TNF-α) in heart tissue in I/R-induced heart. From the results, I/R induction gave a significant increase in QRS interval, QT interval and R-R interval, but showed decrease in all hemodynamic parameters. I/R induction resulted in increased TNF-α level. Treatment of G-Re at 30 and 100 μM doses before I/R induction significantly prevented the decrease in hemodynamic parameters, ameliorated the electrocardiographic abnormality, and inhibited TNF-α level. In this study, G-Re at 100 μM dose exerted more beneficial effects on cardiac function and preservation of myocardium in I/R injury than 30 μM. Collectively, these results indicate that G-Re has distinct cardioprotectective effects in I/R induced rat heart.
PMCID: PMC3818954  PMID: 24198653
Panax ginseng; Ginsenoside-Re; Cardiac injury; Hemodynamics; Myocardial preservation
11.  The application of PET-CT to post-mastectomy regional radiation therapy using a deformable image registration 
To evaluate the utility of the preoperative PET-CT using deformable image registration (DIR) in the treatment of patients with locally advanced breast cancer and to find appropriate radiotherapy technique for further adequate treatment of axillary nodal area.
Sixty-five breast cancer patients who had level II, III axillary or supraclavicular lymph node metastasis on 18F-FDG PET-CT and received postoperative radiotherapy after modified radical mastectomy were enrolled. One radiation oncologist contoured normal organs (axillary vessels, clavicular head, coracoids process and humeral head) and involved lymph nodes on PET-CT and simulation CT slices. After contouring, deformable image registration of PET-CT on simulation CT was carried out. To evaluate the performance of the DIR, Dice similarity coefficient (DSC) and Center of mass (COM) were used. We created two plans, one was the historically designed three field plan and the other was the modified plan based on the location of axillary lymph node, and we compared the doses that irradiated the axillary lymph nodes.
The DSCs for axillary artery, axillary vein, clavicular head, coracoids process and humeral head were 0.43 ± 0.15, 0.39 ± 0.20, 0.85 ± 0.10, 0.72 ± 0.20 and 0.77 ± 0.20, respectively. The distances between the COMs of axillary artery, axillary vein, clavicular head, coracoids process and humeral head in simulation CT and from PET-CT were 13.0 ±7.1, 20.2 ± 11.2, 4.4 ± 6.3, 3.7 ± 6.7, and 9.5 ± 25.0 mm, respectively. In the historically designed plan, only 57.7% of level II lymph nodes received more than 95% of prescribed dose and the coverage was improved to 70.0% with the modified plan (p < 0.01). For level III lymph nodes, the volumes received more than 95% of prescribed dose were similar in both plans (96.8 % vs 97.9%, p = 0.35).
Deformable image registration of PET-CT on simulation CT was helpful in the identification of the location of the preoperatively involved axillary lymph node. Historically designed three-field plan was not adequate to treat the axillary level II lymph node area. Novel treatment technique based on the location of axillary lymph node from PET-CT using DIR can result in more adequate coverage of nodal area.
PMCID: PMC3698158  PMID: 23621896
Breast cancer; Deformable image registration (DIR); Radiotherapy; PET-CT
12.  HIV Transmissions by Stage in Dynamic Sexual Partnerships 
Journal of Theoretical Biology  2012;298:147-153.
Most models assessing relative transmissions during different progressive stages of human immunodeficiency virus (HIV) infection assume that infections are transmitted through instantaneous sexual contacts. In reality, however, HIV will often be transmitted through repeated sex acts during partnerships that form and dissolve at varying rates. We sought to understand how dynamic sexual partnerships would influence transmissions during different progression stages of HIV infection: primary HIV infection (PHI) and chronic stage. Using a system of ordinary differential equations with a pair approximation technique, we constructed a model of HIV transmission in a homogeneous population in which sexual partnerships form and dissolve. We derived analytical expressions for useful epidemiological quantities such as basic reproduction number and also did simulation runs of the model. Partnership dynamics strongly influence transmissions during progressive stages of HIV infection. The fraction of transmissions during PHI has a U-shaped relationship with respect to the rate of partnership change, where the minimum and maximum occur given partnerships of about 100 days and fixed partnerships, respectively. Models that assume instantaneous contacts may overestimate transmissions during PHI for real, dynamic sexual partnerships with varying (non-zero) durations.
PMCID: PMC3288157  PMID: 22261263
primary HIV infection; transmission model; network; pair approximation
13.  Cases report of unicentric Castleman's disease: revisit of radiotherapy role 
Radiation Oncology Journal  2013;31(1):48-54.
Castleman's disease or angiofollicular lymph node hyperplasia is a rare lymphoproliferative disorder. Complete surgical resection was recommended in unicentric Castleman's disease. Radiotherapy was considered alternative therapeutic option. However, there have been consistent favorable responses to radiotherapy. We also experienced two cases of uncentric Castleman's disease salvaged successfully with radiotherapy. This paper described these cases and reviewed the literature about Castleman's disease treated with radiotherapy. Reviewed cases showed that radiotherapy is a successful treatment option in unicentric Castleman's disease. Furthermore, our report confirms the radiotherapy role in uncentric Castleman's disease.
PMCID: PMC3633231  PMID: 23620869
Castleman's disease; Hyaline-vascular; Radiotherapy
14.  Postoperative radiotherapy for ependymoma 
Radiation Oncology Journal  2012;30(4):158-164.
To evaluated the patterns of failure, survival rate, treatment-related toxicity and prognostic factors in postoperative radiotherapy of patients with ependymoma.
Materials and Methods
Thirty patients who underwent surgery and postoperative radiotherapy for ependymoma between the period of June 1994 and June 2008 were reviewed retrospectively. The age of patients ranged from 21 months to 66 years (median, 19 years). Seventeen patients had grade II ependymoma, and 13 had grade III anaplastic ependymoma according to the World Health Organization grading system. The postoperative irradiation was performed with 4 or 6 MV photon beam with median dose of 52.8 Gy (range, 45 to 63 Gy), and radiation field including 2 cm beyond the preoperative tumor volume. Median follow-up period was 51 months (range, 12 to 172 months).
Fourteen out of 30 (46.7%) patients experienced recurrence, and 12 of those died. Among those 14 patients who experienced recurrence, 11 were in-field and 3 were out-of-field recurrence. The 5-year overall survival (OS) and progression-free survival (PFS) rates were 66.7% and 56.1%, respectively. On univariate analysis, tumor grade was a statistically significant prognostic factor for OS and PFS. There were two complications after surgery and postoperative radiotherapy, including short stature and facial palsy on the left side.
We observed good survival rates, and histologic grade was a prognostic factor affecting the OS and PFS. Almost all recurrence occurred in primary tumor site, thus we suggest further evaluation on intensity-modulated radiotherapy or stereotatic radiosurgery for high-risk patients such as who have anaplastic ependymoma.
PMCID: PMC3546283  PMID: 23346534
Ependymoma; Anaplastic ependymoma; Radiotherapy; Histologic grade; Stereotatic radiosurgery
15.  Prognostic value of 18F-fluorodeoxyglucose positron emission tomography, computed tomography and magnetic resonance imaging in oral cavity squamous cell carcinoma with pathologically positive neck lymph node 
Radiation Oncology Journal  2012;30(4):173-181.
To evaluate the prognostic value of preoperative neck lymph node (LN) assessment with 18F-fluorodeoxyglucose positron emission tomography (18F-FDG PET), computed tomography (CT), and magnetic resonance imaging (MRI) in oral cavity squamous cell carcinoma (OSCC) patients with pathologically positive LN.
Materials and Methods
In total, 47 OSCC patients with pathologically positive LN were retrospectively reviewed with preoperative 18F-FDG PET and CT/MRI. All patients underwent surgical resection, neck dissection and postoperative adjuvant radiotherapy and/or chemotherapy between March 2002 and October 2010. Histologic correlation was performed for findings of 18F-FDG PET and CT/MRI.
Thirty-six (76.6%) of 47 cases were correctly diagnosed with neck LN metastasis by 18F-FDG PET and 32 (68.1%) of 47 cases were correctly diagnosed by CT/MRI. Follow-up ranged from 20 to 114 months (median, 56 months). Clinically negative nodal status evaluated by 18F-FDG PET or CT/MRI revealed a trend toward better clinical outcomes in terms of overall survival, disease-free survival, local recurrence-free survival, regional nodal recurrence-free survival, and distant metastasis-free survival rates even though the trends were not statistically significant. However, there was no impact of neck node standardized uptake value (SUVmax) on clinical outcomes. Notably, SUVmax showed significant correlation with tumor size in LN (p < 0.01, R2 = 0.62). PET and CT/MRI status of LN also had significant correlation with the size of intranodal tumor deposit (p < 0.05, R2 = 0.37 and p < 0.01, R2 = 0.48, respectively).
18F-FDG PET and CT/MRI at the neck LNs might improve risk stratification in OSCC patients with pathologically positive neck LN in this study, even without significant prognostic value of SUVmax.
PMCID: PMC3546285  PMID: 23346536
Oral cavity squamous cell carcinoma; Neck lymph node; Magnetic resonance imaging; X-ray computed tomography; 18F-FDG PET; Prognostic value
16.  Dermoscopy: A Useful Tool for the Diagnosis of Angiokeratoma 
Annals of Dermatology  2012;24(4):468-471.
Angiokeratoma is a rare vascular malformation of the upper dermis that presents clinically as deep red to blue-black in color and tends to take a diverse configuration without self-limiting. Here, we reported dermoscopic findings by two cases of angiokeratoma; solitary angiokeratoma and angiokeratoma circumscriptum. A 24-year-old male presented with a 2-months history of 5 mm sized black colored papule on the right buttock. A dermoscopic pattern characterized by red and dark lacunae, whitish veil covered with scale. A 26-year-old woman presented with multiple, 2~10 mm, dark colored papules on the anterior neck with zosteriform fashion since childhood. A dermoscopic pattern presented by red lacunae intermingled with whitish veil. As a previous report, our two cases was the most common dermoscopic pattern of angiokeratoma; red lacunae and whitish veil. Angiokeratoma is often diagnosed as melanocytic nevi, Spitz nevi, malignant melanomas, pigmented basal cell carcinomas, seborrheic keratoses, dermatofibromas and other vascular lesions including hemangiomas and pyogenic granulomas. However, in the dermoscopic view, these above lesions hardly show red lacunae with whitish veils. Therefore, the dermscopic view is a useful differential method of angiokeratoma.
PMCID: PMC3505781  PMID: 23197916
Angiokeratoma; Dermoscopy
17.  Transorbital Penetrating Intracranial Injury by a Chopstick 
A 38-year-old man fell from a chair with a chopstick in his hand. The chopstick penetrated his left eye. He noticed pain, swelling, and numbness around his left eye. On physical examination, a linear wound was noted at the medial aspect of the left eyelid. Noncontrast computed tomography (CT) study showed a linear hypodense structure extending from the medial aspect of the left orbit to the occipital bone, suggesting a foreign body. This foreign body was hyperdense relative to normal parenchyma. From a CT scan with 3-dimensional reconstruction, the foreign body was found to be passing through the optic canal into the cranium. The clear plastic chopstick was withdrawn without difficulty. The patient was discharged home 3 weeks after his surgery. A treatment plan for a transorbital penetrating injury should be determined by a multidisciplinary team, with input from neurosurgeons and ophthalmologists.
PMCID: PMC3488655  PMID: 23133735
Penetrating; Foreign body; Orbit; Craniocerebral trauma
18.  Isolation and Characterization of Chorionic Mesenchymal Stromal Cells from Human Full Term Placenta 
Journal of Korean Medical Science  2012;27(8):857-863.
This study focused on the characterization of mesenchymal stromal cells (MSCs) from the chorion of human full term placenta from 15 donors. Chorionic MSCs revealed homologous fibroblast-like morphology and expressed CD73, CD29, CD105, and CD90. The hematopoietic stem cell markers including HLA DR, CD11b, CD34, CD79a, and CD45 were not expressed. The growth kinetics of their serial passage was steady at the later passages (passage 10). The multilineage capability of chorionic MSCs was demonstrated by successful adipogenic, osteogenic and chondrogenic differentiation and associated gene expression. Chorionic MSCs expressed genes associated with undifferentiated cells (NANOG, OCT4, REX1) and cardiogenic or neurogenic markers such as SOX2, FGF4, NES, MAP2, and NF. TERT was negative in all the samples. These findings suggest that chorionic MSCs undifferentiated stem cells and less likely to be transformed into cancer cells. A low HLA DR expression suggests that chorionic MSCs may serve as a great source of stem cells for transplantation because of their immune-privileged status and their immunosuppressive effect. Based on these unique properties, it is concluded that chorionic MSCs are pluripotent stem cells that are probably less differentiated than BM-MSCs, and they have considerable potential for use in cell-based therapies.
PMCID: PMC3410231  PMID: 22876050
Chorion; Mesenchymal Stromal Cells; Human Placenta; Gene Expression
19.  Anti-apoptotic Activity of Ginsenoside Rb1 in Hydrogen Peroxide-treated Chondrocytes: Stabilization of Mitochondria and the Inhibition of Caspase-3 
Journal of Ginseng Research  2012;36(3):242-247.
Chondrocyte apoptosis has been recognized as an important factor in the pathogenesis of osteoarthritis (OA). Hydrogen peroxide (H2O2), which produces reactive oxygen species, reportedly induces apoptosis in chondrocytes. The ginsenoside Rb1 (GRb1) is the principal component in ginseng and has been shown to have a variety of biological activities, such as anti-arthritis, anti-inflammation, and anti-tumor activities. In this study, we evaluated the effects of G-Rb1 on the mitochondrial permeability transition (MPT) and caspase-3 activity of chondrocyte apoptosis induced by H2O2. Cultured rat articular chondrocytes were exposed to H2O2 with or without G-Rb1 and assessed for viability, MPT, Bcl-xL/Bax expression, caspase-3 activity, and apoptosis. The co-treatment with G-Rb1 showed an inhibition of MPT, caspase-3 activity, and cell death. Additionally, the levels of the apoptotic protein Bax were significantly lower and the levels of the anti-apoptotic protein Bcl-xL were higher compared with H2O2 treatment alone. The results of this study demonstrate that G-Rb1 protects chondrocytes against H2O2-induced apoptosis, at least in part via the inhibition of MPT and caspase-3 activity. These results demonstrate that G-Rb1 is a potentially useful drug for the treatment of OA patients.
PMCID: PMC3659597  PMID: 23717124
Ginsenoside Rb1; Hydrogen peroxide; Chondrocytes; Apoptosis; Caspase-3
20.  Low-dose external beam radiotherapy as a postoperative treatment for patients with diffuse pigmented villonodular synovitis of the knee 
Acta Orthopaedica  2012;83(3):256-260.
Background and purpose
Pigmented villonodular synovitis (PVNS) is a rare proliferative disorder involving synovial membranes, and patients with PVNS have a variable prognosis. We retrospectively analyzed clinical outcomes after synovectomy plus low-dose external beam radiotherapy for diffuse PVNS of the knee.
We reviewed the medical records of 23 patients who underwent postoperative radiotherapy between 1998 and 2007. 19 patients had primary disease and 4 had recurrent disease with an average of 2.5 prior surgeries. After synovectomy (17 arthroscopic surgeries; 6 open), all 23 patients received 4-MV or 6-MV external beam radiotherapy with a median dose of 20 (12–34) Gy in 10 fractions.
At a median follow-up of 9 (0.8–12) years, 4 patients had recurrent disease, with a median disease-free interval of 5 years. Of these 4 patients, 3 received salvage synovectomy and regained local control. Univariate analysis showed that age, sex, history of trauma, and total dose of radiation were not predictive of local control. 22 patients reported excellent or good joint function, and 1 who refused salvage synovectomy had poor joint function. None of the patients experienced grade 3 or higher radiation-related toxicity or radiation-induced secondary malignancies.
Postoperative external beam radiotherapy is an effective and acceptable modality to prevent local recurrence and preserve joint function in patients with diffuse PVNS of the knee. Low-dose (20 Gy) radiotherapy appears to be as effective as moderate-dose treatment (around 35 Gy).
PMCID: PMC3369151  PMID: 22489888
21.  Generation of CD2+CD8+ NK Cells from c-kit+ Bone Marrow Cells in Porcine 
Natural killer (NK) cells provide one of the initial barriers of cellular host defense against pathogens, in particular intracellular pathogens. Because bone marrow-derived hematopoietic stem cells (HSCs), lymphoid protenitors, can give rise to NK cells, NK ontogeny has been considered to be exclusively lymphoid. Here, we show that porcine c-kit+ bone marrow cells (c-kit+ BM cells) develop into NK cells in vitro in the presence of various cytokines [interleukin (IL)-2, IL-7, IL-15, IL-21, stem cell factor (SCF), and fms-like tyrosine kinase-3 ligand (FLT3L)]. Adding hydrocortisone (HDC) and stromal cells greatly increases the frequency of c-kit+ BM cells that give rise to CD2+CD8+ NK cells. Also, intracellular levels of perforin, granzyme B, and NKG2D were determined by RT-PCR and western blotting analysis. It was found that of perforin, granzyme B, and NKG2D levels significantly were increased in cytokine-stimulated c-kit+ BM cells than those of controls. And, we compared the ability of the cytotoxicity of CD2+CD8+ NK cells differentiated by cytokines from c-kit+ BM cells against K562 target cells for 28 days. Cytokines-induced NK cells as effector cells were incubated with K562 cells as target in a ratio of 100:1 for 4 h once a week. In results, CD2+CD8+ NK cells induced by cytokines and stromal cells showed a significantly increased cytotoxicity 21 days later. Whereas, our results indicated that c-kit+ BM cells not pretreated with cytokines have lower levels of cytotoxicity. Taken together, this study suggests that cytokines-induced NK cells from porcine c-kit+ BM cells may be used as adoptive transfer therapy if the known obstacles to xenografting (e.g. immune and non-immune problems) were overcome in the future.
PMCID: PMC3394918  PMID: 22802697
Hematopoietic stem cells; Natural killer cells; Differentiation; Cytokines; Cytotoxicity
22.  Protective Effect of Ginsenoside Rb1 on Hydrogen Peroxide-induced Oxidative Stress in Rat Articular Chondrocytes 
Journal of Ginseng Research  2012;36(2):161-168.
The abnormal maturation and ossification of articular chondrocytes play a central role in the pathogenesis of osteoarthritis (OA). Inhibiting the enzymatic degradation of the extracellular matrix and maintaining the cellular phenotype are two of the major goals of interest in managing OA. Ginseng is frequently taken orally, as a crude substance, as a traditional medicine in Asian countries. Ginsenoside Rb1, a major component of ginseng that contains an aglycone with a dammarane skeleton, has been reported to exhibit various biological activities, including anti-inflammatory and anti-tumor effects. However, a chondroprotective effect of ginsenoside Rb1 related to OA has not yet been reported. The purpose of this study was to demonstrate the chondroprotective effect of ginsenoside Rb1 on the regulation of pro-inflammatory factors and chondrogenic genes. Cultured rat articular chondrocytes were treated with 100 μM ginsenoside Rb1 and/or 500 μM hydrogen peroxide (H2O2) and assessed for viability, reactive oxygen species production, nitric oxide (NO) release, and chondrogenic gene expression. Ginsenoside Rb1 treatment resulted in reductions in the levels of pro-inflammatory cytokine and NO in H2O2-treated chondrocytes. The expression levels of chondrogenic genes, such as type II collagen and SOX9, were increased in the presence of ginsenoside Rb1, whereas the expression levels of inflammatory genes related to chondrocytes, such as MMP1 and MMP13, were reduced by approximately 50%. These results suggest that ginsenoside Rb1 has potential for use as a therapeutic agent in OA patients.
PMCID: PMC3659580  PMID: 23717116
Panax ginseng; Ginsenoside Rb1; Inflammation; Hydrogen peroxide; Chondrocytes; Osteoarthritis
23.  Hypertensive crisis during wide excision of gastrointestinal stromal cell tumor (GIST): Undiagnosed paraganglioma -A case report- 
Korean Journal of Anesthesiology  2012;62(3):289-292.
Although paraganglioma (PGL), an extra-adrenal retroperitoneal pheochromocytoma (PHEO), is a rare catecholamine-secreting neuroendocrine tumor, it can cause severe hypertensive crisis during anesthesia or surgery if undiagnosed preoperatively. Extraluminal perigastric masses may be presumed to be gastrointestinal stromal tumors (GISTs) or soft tissue sarcomas even when histologic confirmation is not possible. Therefore, without a histologic diagnosis or symptoms of excessive catecholamine secretion, PGL may be mistaken for GIST. We report a case of preoperatively undiagnosed PGL which caused hypertensive crisis during anesthesia for retroperitoneal mass excision.
PMCID: PMC3315663  PMID: 22474560
Gastrointestinal stromal tumor; Hypertensive crisis; Paraganglioma; Pheochromocytoma
24.  Biochemical and Morphological Effects of Hypoxic Environment on Human Embryonic Stem Cells in Long-Term Culture and Differentiating Embryoid Bodies 
Molecules and Cells  2011;31(2):123-132.
The mammalian reproductive tract is known to contain 1.5-5.3% oxygen (O2), but human embryonic stem cells (hESCs) derived from preimplantation embryos are typically cultured under 21% O2 tension. The aim of this study was to investigate the effects of O2 tension on the long-term cul-ture of hESCs and on cell-fate determination during early differentiation. hESCs and embryoid bodies (EBs) were grown under different O2 tensions (3, 12, and 21% O2). The expression of markers associated with pluripotency, em-bryonic germ layers, and hypoxia was analyzed using RT-PCR, immunostaining, and Western blotting. Proliferation, apoptosis, and chromosomal aberrations were examined using BrdU incorporation, caspase-3 immunostaining, and karyotype analysis, respectively. Structural and morpho-logical changes of EBs under different O2 tensions were comparatively examined using azan- and hematoxylineosin staining, and scanning and transmis-sion electron microscopy. Mild hypoxia (12% O2) increased the number of cells expressing Oct4/Nanog and reduced BrdU incorporation and aneuploidy. The percentage of cells positive for active caspase-3, which was high during normoxia (21% O2), gradually decreased when hESCs were continuously cultured under mild hypoxia. EBs subjected to hypoxia (3% O2) exhibited well-differentiated microvilli on their surface, secreted high levels of collagen, and showed enhanced differentiation into primitive endoderm. These changes were associated with increased expression of Foxa2, Sox17, AFP, and GATA4 on the EB periphery. Our data suggest that mild hypoxia facilitates the slow mitotic division of hESCs in long-term culture and reduces the frequency of chromosomal abnormalities and apoptsis. In addition, hypoxia promotes the differentiation of EBs into extraembryonic endoderm.
PMCID: PMC3932683  PMID: 21347709
differentiation; embryoid body; germ-layer; human embryo stem cell; hypoxia
25.  Electric Field Guided Assembly of One-Dimensional Nanostructures for High Performance Sensors 
Sensors (Basel, Switzerland)  2012;12(5):5725-5751.
Various nanowire or nanotube-based devices have been demonstrated to fulfill the anticipated future demands on sensors. To fabricate such devices, electric field-based methods have demonstrated a great potential to integrate one-dimensional nanostructures into various forms. This review paper discusses theoretical and experimental aspects of the working principles, the assembled structures, and the unique functions associated with electric field-based assembly. The challenges and opportunities of the assembly methods are addressed in conjunction with future directions toward high performance sensors.
PMCID: PMC3386709  PMID: 22778610
review; electric field; nanowire; nanotubes; assembly; sensors

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