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Lee WJ, Park GH, Kang SM, Lee MW, Choi JH, Moon KC, Koh JK. Adult T-cell leukaemia/lymphoma presenting as a contact dermatitis-like localized patch. J Eur Acad Dermatol Venereol 2009; 23:847-9. [PMID: 19207648 DOI: 10.1111/j.1468-3083.2008.03048.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Qin X, Kang SM, Cho YJ. Convergence theorems on generalized equilibrium problems and fixed point problems with applications. PROCEEDINGS OF THE ESTONIAN ACADEMY OF SCIENCES 2009. [DOI: 10.3176/proc.2009.3.04] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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Song WY, Shin TI, Kang SM, Kim SW, Yang JH, Park MH, Yang CW, Yoon DH. Controllable dimension of ZnO nanowalls on GaN/c-Al2O3 substrate by vapor phase epitaxy method. JOURNAL OF NANOSCIENCE AND NANOTECHNOLOGY 2008; 8:4783-4786. [PMID: 19049108 DOI: 10.1166/jnn.2008.ic52] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
Vertically well-aligned ZnO nanowalls were successfully synthesized at 950-1050 degrees C. Ar gas was introduced into the furnace at a flow rate of 2000-2500 sccm. An Au thin film with a thickness of 3 nm was used as a catalyst. The ZnO nanowalls were successfully grown on the substrate and most of them had nearly the same thickness and were oriented perpendicular to the substrate. The morphology and chemical composition of the ZnO nanowalls were examined as a function of the growth conditions examined. It was found that the grown ZnO nanowalls have a single-crystalline hexagonal structure and preferred c-axis growth orientation based on the X-ray diffraction and high-resolution transmission electron microscope measurements. The room temperature photoluminescence showed a strong free-exciton emission band with negligible deep level emission, indicating the high optical property of our ZnO nanowall samples.
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Kang SM, Yoon SG, Kim SW, Yoon DH. Luminescence tuning of amorphous Si quantum dots prepared by plasma-enhanced chemical vapor deposition. JOURNAL OF NANOSCIENCE AND NANOTECHNOLOGY 2008; 8:2540-2543. [PMID: 18572680] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
Amorphous Si (a-Si) quantum dots (QDs) embedded in a silicon nitride film were prepared by a plasma-enhanced chemical vapor deposition (PECVD) technique using gaseous mixtures of silane, hydrogen and nitrogen. We observed that the Si QDs had an amorphous structure from the Raman spectroscopy measurement. The Fourier transform infrared (FTIR) spectra showed that the relative transmittance of the SiH bands decreased, but that of the NH bands increased, with increasing nitrogen flow rate. During the deposition of SiNx, the number of dangling bonds of silicon acting as nucleation sites increased. As the hydrogen flow rate increased the growth rate decreased, due to the reduction in the hydrogen partial pressure. The hydrogen and nitrogen gas flow rates were found to be important parameters for determining the size of the a-Si QDs. In addition, we observed that the PL peak shifted toward a higher energy with increasing hydrogen and nitrogen gas flow rates, which was attributed to the increase in the quantum confinement effect in the a-Si QDs.
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Kang SM, Choi SH, Park CY, Kim MH, Kim TK, Park JM, Koh MS, Kang HJ, Hwang SB. Monoclonal antibody recognizing N-terminal epitope of hepatitis C virus nonstructural 5B inhibits viral RNA replication. J Viral Hepat 2008; 15:305-13. [PMID: 18307593 DOI: 10.1111/j.1365-2893.2007.00945.x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/09/2022]
Abstract
The nonstructural 5B (NS5B) protein of hepatitis C virus (HCV) is an RNA-dependent RNA polymerase (RdRp) with a key role in HCV replication. To characterize the functional roles of NS5B in HCV replication, we produced a panel of 10 monoclonal antibodies (mAbs) directed against NS5B protein from mice immunized with functionally active RdRp. The epitopes of eight mAbs are localized in the middle region (amino acid 240-263) of NS5B protein. On the other hand, the epitopes of two mAbs are mapped to amino acids 67-88 at the N-terminus of NS5B protein. To examine the effects of mAbs on HCV-RNA replication, we performed in vitro RdRp assay using either the 3'-untranslated region (UTR) or the full-length of HCV-RNA as a template in the presence of each mAb. mAbs specific for the middle region of NS5B had no effect on RdRp activity. Surprisingly, mAb recognizing the N-terminal region of NS5B inhibited RdRp activity in a dose-dependent manner. We have confirmed the same result using the other subclass of mAb, whose epitope is also localized to the same N-terminal region of NS5B. These data show that NS5B contains a B-cell epitope located between amino acid residues 67 and 88. Binding of this epitope with an antibody interferes with the enzymatic function of NS5B.
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Kang SM, Tang Q, Bluestone JA. CD4+CD25+ regulatory T cells in transplantation: progress, challenges and prospects. Am J Transplant 2007; 7:1457-63. [PMID: 17511675 DOI: 10.1111/j.1600-6143.2007.01829.x] [Citation(s) in RCA: 152] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
The involvement of CD4(+)CD25(+) regulatory T cells (Treg) in general immune homeostasis and protection from autoimmune syndromes is now well established. Similarly, there has been increasing evidence for Treg involvement in allograft rejection and current immunotherapies. However, despite significant advances in understanding the development, function, and therapeutic efficacy of Treg in certain well-defined rodent models, the relevance of Treg to clinical transplantation remains unclear. In this review, we summarize our current understanding of the role of Treg in immunity and organ transplantation in experimental and clinical settings. In addition, we review advances in using Treg as a form of immune therapy. The goal is to highlight the complexities and opportunities in the field and to provide evidence to support the use of antigen-specific Tregs in the context of transplantation to facilitate a robust and selective state of immune tolerance.
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Freise CE, Kang SM, Feng S, Posselt A, Hirose K, Hirose R, Stock P. Experience with steroid-free maintenance immunosuppression in simultaneous pancreas-kidney transplantation. Transplant Proc 2004; 36:1067-8. [PMID: 15194370 DOI: 10.1016/j.transproceed.2004.04.017] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
INTRODUCTION Steroid avoidance is possible in simultaneous pancreas-kidney transplantation with the use of newer immunosuppressive agents and induction therapy. We undertook a retrospective consecutive case review of patients treated at a university tertiary referral center. METHODS Medical records of 44 consecutive patients receiving a pancreas-kidney transplant from November 2000 to September 2002 were reviewed. The immunosuppression protocol used in this series of patients consisted of thymoglobulin induction, combined with mycophenolate mofetil, tacrolimus, and sirolimus for maintenance immunosuppression. Steroids were used only while thymoglobulin was given and were typically discontinued by postoperative week 1. Main outcome measures included graft and patient survival rates, rejection rates of the kidney or pancreas, infection rates, and surgical complication rates. RESULTS All 44 patients received a kidney-pancreas transplant with systemic venous anastomosis and enteric drainage of the pancreas. Patient kidney, and pancreas survival rates were 95.6%, 93.2%, and 88.7%, respectively. Biopsy-proven pancreas rejection rates at 1 and 6 months posttransplant were 2.3% and 2.3%. Kidney rejection rates at 1 and 6 months were 2.3% and 4.6%. Reasons for patient loss included one death from sepsis and one cardiovascular death. Reasons for kidney loss besides death included a thrombotic microangiopathy. Reasons for pancreas loss included three thromboses, one mild rejection/infection, and one duodenal segment leak with infection. All patients who have been free of rejection have been off steroids for the duration of follow-up. CONCLUSIONS Newer immunosuppression protocols without maintenance steroids are possible with minimal rejection in the first 3 months and equivalent patient and graft survival rates compared with earlier protocols utilizing steroids. The potential beneficial long-term impact of steroid avoidance will require further study.
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Meng MV, Kang SM, Duh QY, Stoller ML, Freise C. Laparoscopic live donor nephrectomy at the University of California San Francisco. CLINICAL TRANSPLANTS 2002:113-21. [PMID: 12211773] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/26/2023]
Abstract
Laparoscopic donor nephrectomy is quickly becoming the preferred technique for kidney retrieval, since it removes many of the disincentives of kidney donation. Our experience at UCSF has confirmed that the procedure is safe, with excellent donor recovery. The transplanted kidney appears to function as well as any kidney retrieved using an open technique, at least in the short-term. Development of a successful laparoscopic donor program is best done initially with a team approach, utilizing the skills of an advanced laparoscopic surgeon, and with careful patient selection. With time, the technique can be done well by properly trained transplant surgeons with basic laparoscopic skills, with or without a hand-assist technique. As experience grows, this procedure can be applied to virtually every potential donor, and hopefully will improve live kidney donation rates.
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Maeda K, Nishiguchi Y, Kang SM, Yashiro M, Onoda N, Sawada T, Ishikawa T, Hirakawa K. Expression of thrombospondin-1 inversely correlated with tumor vascularity and hematogenous metastasis in colon cancer. Oncol Rep 2001; 8:763-6. [PMID: 11410779 DOI: 10.3892/or.8.4.763] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Solid tumors require neovascularization for growth and metastasis. Angiogenesis depends on the local balance between various molecules that induce and inhibit neovascularization. Thrombospondin-1 (TSP-1) is thought to be an antiangiogenic factor. In this study, we examined the correlation between expression of TSP-1 and tumor vascularity, and determined its prognostic significance in colon cancer. Microvessel density, determined by immunostaining for factor VIII-related antigen, was significantly higher in tumors that were TSP-1-negative. TSP-1 expression was inversely correlated with prognosis. Patients with TSP-1-negative tumors had a significantly worse prognosis than did those with TSP-1-positive tumors. Frequency of hepatic recurrence was significantly higher in patients with tumors that were TSP-1-negative. In conclusion, TSP-1 is an important negative-regulator of tumor angiogenesis, and TSP-1 may be useful for predicting recurrence in patients with colon cancer.
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Ogawa M, Onoda N, Maeda K, Kato Y, Nakata B, Kang SM, Sowa M, Hirakawa K. A combination analysis of p53 and p21 in gastric carcinoma as a strong indicator for prognosis. Int J Mol Med 2001; 7:479-83. [PMID: 11295107 DOI: 10.3892/ijmm.7.5.479] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
We studied p53 and p21 expression simultaneously in gastric carcinoma tissues to investigate the clinical significance of p53-p21 pathway in this disease. One hundred sixty-four primary gastric carcinoma specimens were immunohistochemically stained for p53 and p21 protein, and clinicopathological features of the cases were examined. P53 was stained negatively, while p21 was stained positively in each normal stomach epithelium. P53, and p21 positive staining was observed in 82 (50%) and 61 (37.2%) tumors, respectively. Unexpectingly, no correlation was found between p53 and p21 staining status. Tumors demonstrating preserved p53-p21 pathway [p53(-)/p21(+)], observed in 20.1% of the tumors, displayed less aggressive characteristics, and no recurrent disease after curative resection. While tumors demonstrating disrupted p53-p21 pathway [p53(+)/p21(-)], observed in 32.9% of the tumors, displayed significantly more aggressive characteristics, poorer survival and higher recurrence rate than the tumors demonstrating other staining patterns. P53-p21 pathway was widely altered in gastric carcinomas. The combined evaluation of p53 and p21 expression in gastric carcinoma tissues is suggested to have clinical importance by indicating not only the malignant potential of each tumor, but also the prognosis of this disease.
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Zatzick DF, Kang SM, Hinton WL, Kelly RH, Hilty DM, Franz CE, Le L, Kravitz RL. Posttraumatic concerns: a patient-centered approach to outcome assessment after traumatic physical injury. Med Care 2001; 39:327-39. [PMID: 11329520 DOI: 10.1097/00005650-200104000-00004] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
BACKGROUND Approximately 2.5 million Americans are admitted to the hospital after traumatic physical injury each year. Few investigations have elicited patients' perspectives regarding posttraumatic outcomes. OBJECTIVE To identify and categorize physically injured trauma survivors' posttraumatic concerns. RESEARCH DESIGN Prospective longitudinal investigation; trauma survivors were interviewed during the post-injury hospitalization and again 1, 4, and 12 months after the trauma. SUBJECTS Ninety-seven, randomly selected, English speaking, hospitalized survivors of motor vehicle-crashes or assaults. MEASURES At the end of each interview patients were asked, "Of all the things that have happened to you since you were injured, what concerns you the most?" Using an iterative process and working by consensus, investigators categorized patient concerns in content domains. Concern domains were then compared with established measures of posttraumatic stress disorder (PTSD) symptoms and limitations in physical functioning. RESULTS Seven categories of posttraumatic concerns were identified. During the course of the year, 73% of patients expressed physical health concerns, 58% psychological concerns, 53% work and finance concerns, 40% social concerns, 10% legal concerns, 10% medical concerns, and 20% uncodable concerns. Rater agreement on concern categorization was substantial (kappa = 0.72). The mean number of concerns expressed per patient gradually decreased over time (1 month mean = 1.51; 12 month mean = 1.26) and resembled the trajectories of PTSD symptoms and functional limitations. CONCLUSIONS The concerns of physically injured trauma survivors are readily elicited and followed up during the course of the year after injury. Open-ended inquiry regarding posttraumatic concerns may complement standardized outcome assessments by identifying and contextualizing the outcomes of greatest importance to patients.
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Ko YG, Ha JW, Chung N, Shim WH, Kang SM, Rim SJ, Jang Y, Cho SY, Kim SS. Effects of left atrial compliance on left atrial pressure in pure mitral stenosis. Catheter Cardiovasc Interv 2001; 52:328-33. [PMID: 11246247 DOI: 10.1002/ccd.1076] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
In mitral stenosis (MS), left atrial (LA) pressure is commonly elevated because of increased LA afterload. There is a wide spectrum of LA pressure in patients with MS, however, despite a similar mitral valve orifice area. LA compliance is an important determinant of both cardiovascular performance and pathological physiology. Few data are available, however, regarding the effects of LA compliance on LA pressure. We hypothesized that LA pressure may be higher in patients with decreased LA compliance. We analyzed the right heart and transseptal catheterization data in 47 patients (41 female, mean age 40 +/- 10 years) with pure MS and sinus rhythm. The magnitude of LA a and v waves was measured from transseptal catheterization. Fick's method was used to determine cardiac output. LA compliance was calculated by dividing the systolic rise in LA pressure (DeltaP(LA) = P(LA(v)) - P(LA(x))) into the stroke volume. LA size, mitral valve area (MVA), mean diastolic pressure gradient (MG), left ventricular (LV) end-diastolic and end-systolic dimensions were obtained by using two-dimensional and Doppler echocardiography. Multiple regression analysis was performed to identify independent factors determining LA pressure. The mean MVA was 0.95 +/- 0.22 cm(2). MG and LA dimension were 11.2 +/- 5.2 mm Hg and 50.6 +/- 5.2 mm, respectively. The mean LA pressure and cardiac output obtained by cardiac catheterization were 23.4 +/- 8.4 mm Hg and 4.3 +/- 1.5 L/min, respectively. The calculated LA compliance was 4.9 +/- 2.8 cm(3)/mm Hg. Univariate analysis showed that factors associated with increased LA pressure were smaller MVA (r = -0.33, P < 0.05), higher MG (r = 0.69, P < 0.01) and lower LA compliance (r = -0.55, P < 0.01); among them, MG (beta coefficient 0.59, SE 0.19, P < 0.01) and LA compliance (beta coefficient -0.26, standard error 0.34, P < 0.05) were the strongest predictors of LA pressure. In conclusion, LA compliance, along with MG that reflects the severity of MS, is an important contributing factor determining LA pressure in patients with pure MS and sinus rhythm.
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Kang SM, Ha JW, Chung N, Jang KJ, Shin MS, Rim SJ, Cho SY. Assessment of elastic properties of the descending thoracic aorta by transesophageal echocardiography with acoustic quantification in patients with a stroke. Echocardiography 2000; 17:713-20. [PMID: 11153017 DOI: 10.1111/j.1540-8175.2000.tb01224.x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Abstract
Previous studies have described the use of transesophageal echocardiography (TEE) with acoustic quantification (AQ) in assessing aortic elastic properties. We hypothesized that patients with a prior history of stroke (ST) may have a higher risk of atherosclerotic change in great vessels compared to nonstroke subjects (NST) and thus have decreased elastic properties. We assessed the elastic properties of the descending thoracic aorta (DTA) by TEE in ST patients and compared them with data in NST patients. Subjects included 31 with ST without any evidence of emboli originating from the heart (age 51 +/- 10 years, M:F = 20:11) and 25 age-matched NST (M:F = 8:17). Patients with significant valvular heart disease including aortic and mitral regurgitation, left ventricular dysfunction (ejection fraction < 55%), and congenital heart disease were excluded. Compliance (C), distensibility (D), and stiffness index (SI) were measured using AQ and M-mode measurement at a level of the left atrium. We scored atherosclerotic risk factors (ARF) such as a history of diabetes, hypertension, smoking, hypercholesterolemia, and the presence of atheroma of DTA. There was no evidence of atheroma of DTA in NST. There were no significant differences in heart rate and systolic and diastolic blood pressure between ST and NST patients. Fractional area change (FAC) of DTA was significantly lower in ST than in NST patients (3.2 +/- 1.6 vs 5.4 +/- 2.5%, P = 0.000). ST patients had significantly lower C (1.2 +/- 0.4 vs 1.5 +/- 0.7 x 10(-3) cm2 mmHg(-1), P = 0.039), lower D (0.8 +/- 0.3 vs 1.5 +/- 0.8 x 10(-3) mmHg(-1), P = 0.000), and higher SI (10.3 +/- 8.8 vs 5.3 +/- 2.9, P = 0.006) than NST patients. ST patients without atheroma of DTA (n = 21) also had significantly lower C (1.1 +/- 0.4 vs 1.5 +/- 0.7 x 10(-3) cm2 mmHg(-1), P = 0.038) and lower D (3.5 +/- 1.4 vs 4.8 +/- 2.4 x 10(-3) mmHg(-1), P = 0.021) than NST patients. There was a significant positive correlation between SI and the score of ARF (r = 0.51, P = 0.000). The regional elastic properties of DTA measured by TEE with AQ and M-mode method were abnormal in ST. Therefore, TEE with AQ technique may have a possible clinical application for the detection of early atherosclerotic changes such as alteration of elastic properties in morphological normal DTA.
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Kwon HM, Hong BK, Kang TS, Kwon K, Kim HK, Jang Y, Choi D, Park HY, Kang SM, Cho SY, Kim HS. Expression of osteopontin in calcified coronary atherosclerotic plaques. J Korean Med Sci 2000; 15:485-93. [PMID: 11068982 PMCID: PMC3054686 DOI: 10.3346/jkms.2000.15.5.485] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Advanced atherosclerosis is often associated with dystrophic calcification and remodeling of extracellular matrix of vascular wall. Recently many studies have documented a general relationship between calcification and severity of coronary disease, and discussed the feasibility of electron beam computed tomography for detecting and quantifying the coronary artery calcification in the patients. The present study investigated the expression and the localization of osteopontin, one of noncollagenous bone matrix protein, within the calcified coronary arteries. Autopsy-derived coronary artery specimens were scanned and reconstructed to visualize the pattern of coronary calcification using a novel microscopic computed tomography technique. The localization of the osteopontin were evaluated by immunohistochemial stain with LF7. The present study showed that the pattern of coronary calcification is variable and the expression of osteopontin is localized mainly to calcified lesion. The smooth muscle cells in addition to macrophage expressed osteopontin protein in human coronary atherosclerotic plaques. Soluble osteopontin released near to the sites of vascular calcification may represent an adaptive mechanism aimed at regulating the process of vascular calcification.
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Zatzick DF, Kang SM, Kim SY, Leigh P, Kravitz R, Drake C, Sue S, Wisner D. Patients with recognized psychiatric disorders in trauma surgery: incidence, inpatient length of stay, and cost. THE JOURNAL OF TRAUMA 2000; 49:487-95. [PMID: 11003328 DOI: 10.1097/00005373-200009000-00017] [Citation(s) in RCA: 55] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
BACKGROUND Although psychiatric disturbances are highly prevalent among traumatically injured inpatients, few investigations have assessed the impact of these disorders on surgical length of stay (LOS) and cost. METHODS The authors identified all trauma-registry recorded psychiatric diagnoses among patients admitted to University of California Davis Medical Center between January 1993 and December 1996. Linear and logistic regressions were used to assess the unique effects of psychiatric diagnoses on inpatient LOS and cost. RESULTS A total of 29% of patients had one or more registry-recorded psychiatric diagnosis. Patients with alcohol abuse diagnoses demonstrated 10% to 12% decreases in LOS and cost (p < 0.01), whereas patients with stress disorders, delirium, and psychoses demonstrated 46% to 103% increases in LOS and cost (p < 0.01). CONCLUSION Patients with recognized psychiatric disorders uniquely impact inpatient trauma surgery LOS and cost. Additional investigations of the processes and outcomes of care could lead to cost-effective performance improvement efforts that target the amelioration of comorbid psychiatric disorders among physically injured trauma survivors.
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Ha JW, Chung N, Kang SM, Jang KJ, Kim IJ, Rim SJ, Jang Y, Shim WH, Cho SY, Kim SS. Enhanced detection of left atrial spontaneous echo contrast by transthoracic harmonic imaging in mitral stenosis. J Am Soc Echocardiogr 2000; 13:849-54. [PMID: 10980088 DOI: 10.1067/mje.2000.106791] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
BACKGROUND Spontaneous echo contrast (SEC) of the left atrium is associated with increased risk of thromboembolism in patients with mitral stenosis (MS). The determination of the presence and severity of left atrial (LA) SEC is of prognostic importance in these patients. Harmonic imaging (HI), a novel echocardiographic technique that differs from conventional fundamental imaging (FI) in that it involves transmitting ultrasound at one frequency and receiving at twice the transmitted frequency, produces better endocardial border definition and myocardial opacification. However, there are no data about its value for the detection of LA SEC. The purpose of this study was to investigate the utility of transthoracic noncontrast tissue HI in the detection of LA SEC in patients with MS. METHODS Seventy-four consecutive patients with MS (49 women, mean age 51 years) underwent standard transthoracic echocardiography (TTE) in both HI and FI modes and transesophageal echocardiography (TEE) to determine the presence and severity of LA SEC. Left atrial SEC was graded by TEE as either mild (only seen at high gain) or severe (visible in the entire left atrium at normal gain control of the equipment). The control group comprised 30 patients randomly selected from patients who did not have LA SEC at the TEE examination. RESULTS Atrial fibrillation was found in 46 patients (62.2%). The mean mitral valve area and mean mitral gradient were 1.0+/-0.3 cm(2) and 8.2+/-4.1 mm Hg, respectively. Nine patients (12.2%) had episodes of systemic embolism; 8 had stroke, and 1 had peripheral embolism. Left atrial thrombus was found in 11 patients (14.9%) by TEE. Left atrial SEC was present in all but one patient by TEE (mild in 35 patients, severe in 38). Fundamental imaging with TTE, however, revealed LA SEC in only 5 (6.8%) of the 73 patients. In contrast, with HI, LA SEC could be detected in 63 (86.3%) patients. In the detection of severe LA SEC, the sensitivities of FI and HI were 13.2% (5/38) and 100% (38/38), respectively. Left atrial SEC was not observed in control subjects by either FI or HI. CONCLUSIONS Transthoracic HI significantly enhances the detection of LA SEC in patients with MS.
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Kim JS, Rhee Y, Kang SM, Ko WK, Kim YS, Lee JG, Park JM, Kim SK, Kim SK, Lee WY, Chang J. A case of endobronchial aspergilloma. Yonsei Med J 2000; 41:422-5. [PMID: 10957902 DOI: 10.3349/ymj.2000.41.3.422] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
Abstract
Pulmonary aspergillosis may be classified under three categories, depending upon whether the host is atopic or immunocompromised: invasive aspergillosis, allergic bronchopulmonary aspergillosis (ABPA) or aspergilloma. However, it is not always possible to effectively categorize this disease. We experienced a case of endobronchial aspergilloma, which was difficult to categorize, in a healthy male patient. The chest X-ray and computed tomography showed an ill-defined nodule mimicking lung cancer. Fiberoptic bronchoscopy revealed an aspergilloma without cavity formation in the left lower laterobasal segmental bronchial orifice. The aspergilloma was removed and the patient's symptoms were relieved. We present this unusual case with a review of the literature.
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Kang SM, Braat D, Schneider DB, O'Rourke RW, Lin Z, Ascher NL, Dichek DA, Baekkeskov S, Stock PG. A non-cleavable mutant of Fas ligand does not prevent neutrophilic destruction of islet transplants. Transplantation 2000; 69:1813-7. [PMID: 10830216 DOI: 10.1097/00007890-200005150-00014] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
BACKGROUND Fas ligand (FasL) mediates apoptosis of susceptible Fas-expressing lymphocytes, and may contribute to the maintenance of peripheral tolerance. In transplantation models, however, artificial expression of FasL on cellular as well as islet transplants results in accelerated rejection by neutrophils. The mechanism of the neutrophilic response to FasL expression is unknown. FasL, like other members of the tumor necrosis factor family, is cleaved to a soluble form by metalloproteases. We tested the hypothesis that soluble FasL (sFasL) was responsible for neutrophil migration by creating a non-cleavable mutant of FasL. METHODS Three mutants of FasL with serial deletions in the putative proteolytic cleavage site of human FasL were made using inverse polymerase chain reaction. The relative fractions of sFasL and membrane-bound FasL were assessed by Western blot and immunoprecipitation, as well as by cytotoxicity assay using Fas-expressing target cells. The fully non-cleavable mutant was transduced into murine islets as well as myoblasts and tumor cell lines, and tested in a murine transplantation model. RESULTS Serial deletions in the putative metalloprotease site of FasL resulted in a fully non-cleavable mutant of FasL (ncFasL). Expression of ncFasL in tumor lines induced higher levels of apoptosis in Fas bearing targets than wild-type FasL. Transplantation of ncFasL-expressing islets under the kidney capsule of allogenic mice resulted in accelerated rejection identical to that seen with wild-type Fas ligand-expressing islets. Myoblasts and tumor cell lines expressing ncFasL also induced neutrophil infiltration. CONCLUSIONS Membrane-bound Fas ligand is fully capable of inducing a neutrophilic response to transplants, suggesting an activation by Fas ligand of neutrophil chemotactic factors.
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Ha JW, Chung N, Jang Y, Kang WC, Kang SM, Rim SJ, Shim WH, Cho SY, Kim SS. Is the left atrial v. wave the determinant of peak pulmonary artery pressure in patients with pure mitral stenosis? Am J Cardiol 2000; 85:986-91. [PMID: 10760340 DOI: 10.1016/s0002-9149(99)00915-7] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
A large left atrial (LA) v. wave can be observed in patients with pure mitral stenosis (MS) because of decreased LA compliance. Few data are available regarding the relation between the magnitude of the LA v wave and pulmonary artery pressure in MS. We hypothesized that pulmonary artery pressure may be higher in patients with decreased LA compliance and thus a large v. wave. We analyzed the right-sided cardiac and transseptal catheterization data in 113 patients (16 men and 97 women, mean age 39 years) with pure rheumatic MS in sinus rhythm. Peak systolic, diastolic, and mean pulmonary artery pressures were measured with right-sided cardiac catheterization. The magnitude of LA a and v. waves were measured through transseptal catheterization. Two-dimensional and Doppler echocardiography were also performed to measure LA size, mitral valve area, mean mitral gradient, and valvular regurgitation. Multiple regression analysis was performed to identify the most important factor in the determination of pulmonary artery pressure. A large v wave, defined if peak v wave height exceeded the mean LA pressure by > or =10 mm Hg, was observed in 43 of 113 patients (38%). Increased pulmonary artery systolic pressure (> or =50 mm Hg) was observed in 38 patients (34%). Univariate analysis showed that the factors associated with increased pulmonary artery systolic pressure were smaller mitral valve area, higher mean mitral gradient, higher mean LA pressure, and higher LA v. wave; among them, LA v wave (p <0. 001) and mean mitral gradient (p<0.001) were significant independent factors for pulmonary artery systolic pressure in multivariate analysis. In conclusion, in patients with pure MS and sinus rhythm, the magnitude of the LA v. wave is strongly associated with pulmonary artery pressure. This finding may suggest that LA compliance is a major contributing factor determining pulmonary artery pressure in pure MS.
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O'Rourke RW, Kang SM, Lower JA, Feng S, Ascher NL, Baekkeskov S, Stock PG. A dendritic cell line genetically modified to express CTLA4-IG as a means to prolong islet allograft survival. Transplantation 2000; 69:1440-6. [PMID: 10798768 DOI: 10.1097/00007890-200004150-00039] [Citation(s) in RCA: 51] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
BACKGROUND Dendritic cells are potent antigen-presenting cells that bind allogeneic T cells. They are thus candidates for targeting immunoregulatory molecules to the alloreactive T cell compartment and suppressing the alloimmune response. METHOD A dendritic cell line derived from the BALB/c mouse (H2d) was genetically modified to express the immunoregulatory molecule CTLA4-Ig. The ability of these dendritic cell transfectants to downregulate the alloimmune response was tested in an islet transplant model. Allogeneic C57Bl/6 (H2b) mice were rendered diabetic with streptozocin, and they received BALB/c islet (H2d) transplants. Mice were administered 25 million untransfected or CTLA4-Ig-transfected D2SC/1 cells i.v. on the day of islet transplantation and 6 days later[fnc]. RESULT Mice treated with CTLA4-Ig-transfected D2SC/1 cells demonstrated prolonged allograft survival (mean = 20 days, median = 17 days, SD = 9.39) compared with mice treated with untransfected D2SC/1 cells (mean = 12 days, median = 11 days, SD=2.74) or untreated control mice (mean = 11 days, median = 11 days SD = 1.41). Third party allograft survival was not prolonged in mice receiving similar treatment. CONCLUSIONS These results demonstrate that a genetically modified dendritic cell line can suppress the alloimmune response and prolong islet allograft survival in an allospecific manner. The findings also suggest that genetically modified dendritic cells may be useful in targeting alloreactive T cells and prolonging allograft survival.
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Maeda K, Nishiguchi Y, Yashiro M, Yamada S, Onoda N, Sawada T, Kang SM, Hirakawa K. Expression of vascular endothelial growth factor and thrombospondin-1 in colorectal carcinoma. Int J Mol Med 2000; 5:373-8. [PMID: 10719053 DOI: 10.3892/ijmm.5.4.373] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
Abstract
Solid tumors require neovascularization for growth and metastasis. Vascular endothelial growth factor (VEGF) is a well-characterized inducer of angiogenesis, while, thrombospondin-1 (TSP-1) is thought to be an antiangiogenic factor. In this study, we examined the expressions of these antigens and their relationship with microvessel density, and determined their prognostic significance. One hundred specimens resected from patients with colorectal adenocarcinoma were examined using immunohistochemical methods. Microvessel density, determined by immunostaining for factor VIII-related antigen, was significantly higher in tumors that were VEGF-positive and TSP-1-negative than in other tumors. Patients with VEGF-positive tumors had a significantly worse prognosis than did those with VEGF-negative tumors, and TSP-1 expression was inversely correlated with prognosis. The frequency of hepatic recurrence was significantly higher in patients with tumors that were VEGF-positive and TSP-1-negative than in all other patients. In conclusion, VEGF and TSP-1 are important regulators of tumor angiogenesis, and combined analysis of VEGF and TSP-1 may be useful for predicting recurrence in patients with colorectal adenocarcinoma.
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Kang SM, Kwon HM, Hong BK, Kim D, Kim IJ, Choi EY, Jang Y, Kim HS, Kim MS, Kwon HC. Expression of leptin receptor (Ob-R) in human atherosclerotic lesions: potential role in intimal neovascularization. Yonsei Med J 2000; 41:68-75. [PMID: 10731922 DOI: 10.3349/ymj.2000.41.1.68] [Citation(s) in RCA: 53] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
Abstract
Neovascularization of the adventitial vasa vasorum with extension into the intima of atherosclerotic lesions is frequently observed, but its pathophysiological significance is still subject to debate. Recently, leptin, the product of the Ob gene, was identified. Leptin, via activation of the endothelial receptor (Ob-R), generates a growth signal involving a tyrosine kinase-dependent intracellular pathway and promotes angiogenic processes. We hypothesized that a high concentration of leptin within vasa vasorum and plaque itself, may influence inflammatory and vascular neovascularization coupling with functional upregulation of the vascular endothelial growth factor (VEGF). Microscopic computerized tomography was utilized for the spatial distribution of vasa vasorum and intimal neovascularization from atherosclerotic human coronary arteries. Atherosclerotic coronary arteries showed a dense plexus of microvessels in the adventitia and plaque itself. Microscopic analysis from human atherosclerotic aortas revealed an increase in the intimal thickness with neovascularization. The immunoreactivity for Ob-R, VEGF and matrix metalloproteinase (MMP) increased in atherosclerotic plaque, predominantly in the endothelial lining of the intimal neovessel and macrophages/foam cells. Our observation of a prominent colocalization between Ob-R, VEGF and MMP supports this hypothesis and these factors participate in the neovascularization of atherosclerotic lesions. The present study is the first report on vascular tissue and it opens a promising perspective concerning future investigations of leptin-dependent modulation of atherogenesis and vascular neovascularization under pathophysiolgical conditions.
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Hong BK, Kwon HM, Lee BK, Kim D, Kim IJ, Kang SM, Jang Y, Cho SH, Kim HK, Jang BC, Cho SY, Kim HS, Kim MS, Kwon HC, Lee N. Coexpression of cyclooxygenase-2 and matrix metalloproteinases in human aortic atherosclerotic lesions. Yonsei Med J 2000; 41:82-8. [PMID: 10731924 DOI: 10.3349/ymj.2000.41.1.82] [Citation(s) in RCA: 45] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
Abstract
Inflammation appears to have a major role in the development of atherosclerosis. Cyclooxygenase-2 (COX-2) is involved in the inflammatory response via the generation of prostanoids that, in turn, are involved in the production of matrix metalloproteinases (MMPs). This study aimed to investigate atherosclerosis in human aortas for in situ tissue distribution of COX-2, MMPs including MMP-9 and membrane type 1 MMP (MT1-MMP), and tissue inhibitor of metalloproteinase-2 (TIMP-2). Immunohistochemical studies were performed on atherosclerotic lesions of aortas from patients with aortic aneurysms (n = 4) and dissections (n = 3) by using antibodies to COX-2, MMP-9, MT1-MMP, and TIMP-2. Control tissues were obtained from traumatically dissected aortas (n = 2). All specimens from diseased aortas had atherosclerotic lesions ranging from fatty streak to atheromatous plaques. In control, there was no expression of COX-2, MMP-9, and MT1-MMP in all aortic layers. Immunoreactivity for COX-2 was predominantly noted in macrophages and smooth muscle cells (SMCs) of the intima including atherosclerotic plaque itself and the medial layer of the plaque base, as well as in SMCs and endothelial lining of the vasa vasorum in the adventitia. Immunoreactivity for MMP-9 and MT1-MMP was found in the same distribution as that of COX-2. Additionally, the expression of TIMP-2 increased in relation to MMP-9 expression. This study demonstrates that COX-2 is coexpressed with MMP-9 and MT1-MMP, not only by macrophages and SMCs in atherosclerotic lesions, but also in endothelial lining of the vasa vasorum of human aortas. Thus, vascular inflammatory reactions may influence extracellular matrix remodeling by coactivation of MMPs in the development of atherosclerosis and, in turn, the progression of disease.
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Malek AM, Higashida RT, Reilly LM, Smith WS, Kang SM, Gress DR, Meyers PM, Phatouros CC, Halbach VV, Dowd CF. Subclavian arteritis and pseudoaneurysm formation secondary to stent infection. Cardiovasc Intervent Radiol 2000; 23:57-60. [PMID: 10656908 DOI: 10.1007/s002709910009] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
Technically uncomplicated percutaneous angioplasty and stent placement of a left subclavian artery stenosis was performed in a 56-year-old man for treatment of subclavian steal syndrome and vertebrobasilar insufficiency. Six days later the patient was readmitted with Staphylococcus aureus bacteremia and stigmata of septic emboli isolated to the ipsilateral hand. Nine days later he had computed tomography (CT) evidence of a contrast-enhancing phlegmon surrounding the stent. Despite clinical improvement and resolution of bacteremia on intravenous antibiotic therapy, the phlegmon progressed, and at day 21 a pseudoaneurysm was angiographically confirmed. The patient underwent surgical removal of the stented arterial segment and successful autogenous arterial reconstruction. The possible contributory factors leading to stent infection were prolonged right femoral artery access and an infected left arm venous access. Although the role of prophylactic antibiotics remains to be defined, it may be important in cases where the vascular access sheath remains in place for a prolonged period of time.
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Hong BK, Kwon HM, Byun KH, Kim D, Choi EY, Kang TS, Kang SM, Chun KJ, Jang Y, Kim HS, Kim M. Apoptosis in dilated cardiomyopathy. Korean J Intern Med 2000; 15:56-64. [PMID: 10714093 PMCID: PMC4531747 DOI: 10.3904/kjim.2000.15.1.56] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
Abstract
OBJECTIVE Cardiomyopathy, a popular diagnosis that always obscures more than it reveals, nevertheless has several characteristic histological features. These prominently include widespread focal myocardial fibrosis and associated hypertrophy of surviving cardiac myocyte. In fact, focal noninflammatory degeneration (not necrosis) has been demonstrated as a feature of many forms of cardiac hypertrophy. We hypothesized that this loss of myocardial cells in dilated cardiomyopathy (DCMP) may result from cell death by apoptosis. METHODS Endomyocardial biopsy specimens from the right ventricles of six patients who suffered from DCMP were studied, and myocardial specimens from two persons who died in motor vehicle accidents were used as negative controls. For identification of apoptosis, immunohistochemistry with terminal deoxynucleotidyl transferase (TdT)-mediated dUTP-biotin nick end-labeling was performed. In addition, apoptosis was confirmed morphologically by confocal laser scanning microscopy with propidium iodide. RESULTS Apoptosis, that was represented by an apoptotic index ranging from 19.8 to 25.4%, could be extensively seen in myocytes and also rarely in non-myocytes of interstitium and vascular endothelium. Morphologically, there were a lot of nuclei with clumps of condensed chromatin, suggestive of apoptosis. CONCLUSION The present study demonstrated that myocyte loss in DCMP might be mainly due to the apoptosis of myocytes and interstitial cells, rather than inflammation or cell necrosis.
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