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Shin JH, Choi BH, Lim YG, Jeong DU, Park KS. Automatic ballistocardiogram (BCG) beat detection using a template matching approach. ANNUAL INTERNATIONAL CONFERENCE OF THE IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. ANNUAL INTERNATIONAL CONFERENCE 2009; 2008:1144-6. [PMID: 19162866 DOI: 10.1109/iembs.2008.4649363] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
This paper suggests a beat detection method for ballistocardiogram (BCG) from an unconstrained cardiac signal monitoring devices. A fiducial peak point of BCG is an I-J-K complex which corresponds with ventricle contraction and Electrocardiogram (ECG) QRS complex. The goal of the method is extraction of J peak without ECG synchronization. The detection method is based on a "template matching" rule evaluated using a correlation function in a local moving-window procedure. The total beat detection algorithm operates in two stages, template definition stage and beat detection stage with defined template in previous stage. In the first stage, the BCG template is constructed by the expert with an empirical analysis of BCG signal and measurement device. In the second stage, the correlation function calculates an accuracy of template with BCG signal using a local moving-window. The data analysis has been performed on the subjects tested at Seoul National University Hospital Sleep Medicine Center and presents 95.16% of sensitivity and 94.76% of positive predictivity value for the J peak detection.
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Shin JH, Kim YS, Worley PF, Linden DJ. Depolarization-induced slow current in cerebellar Purkinje cells does not require metabotropic glutamate receptor 1. Neuroscience 2009; 162:688-93. [PMID: 19409231 DOI: 10.1016/j.neuroscience.2009.01.044] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2008] [Revised: 01/21/2009] [Accepted: 01/23/2009] [Indexed: 11/16/2022]
Abstract
Activation of cerebellar Purkinje cells by either brief depolarizing steps or bursts of climbing fiber synaptic activation evokes a slow inward current, which we have previously called depolarization-induced slow current or DISC. DISC is triggered by Ca influx via voltage-sensitive Ca channels and is attenuated by inhibitors of vacuolar ATPase or vesicle fusion. This led us to suggest that DISC required vesicular release of glutamate from the somatodendritic region of Purkinje cells. Furthermore, we found that DISC was attenuated by the mGluR1 antagonist 7-(hydroxyimino)cyclopropa[b]chromen-1a-carboxylate ethyl ester (CPCCOEt), indicating that DISC required autocrine activation of metabotropic glutamate receptor 1 (mGluR1). Here, we have revisited the role of mGluR1 and found that it is, in fact, not required for DISC. CPCCOEt, but not three other specific mGluR1 antagonists (JNJ16259685, alpha-amino-5-carboxy-3-methyl-2-thiopheneacetic acid (3-MATIDA), Bay 36-7620), attenuated DISC, even though all four of these drugs produced near-complete blockade of current evoked by puffs of the exogenous mGluR1/5 agonist DHPG. Cerebellar slices derived from mGluR1 null mice showed substantial DISC that was still attenuated by CPCCOEt. mGluR5 is functionally similar to mGluR1, but is not expressed at high levels in cerebellar Purkinje cells. 2-Methyl-6-(phenylethynyl)pyridine hydrochloride (MPEP), an mGluR5 antagonist, did not attenuate DISC, and DISC was still present in Purkinje cells derived from mGluR1/mGluR5 double null mice. Thus, neither mGluR1 nor mGluR5 is required for DISC in cerebellar Purkinje cells.
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Park BS, Park YJ, Kim YJ, Kang SW, Kim YH, Shin JH, Yoon YC, Kim YW. A case of disseminated Nocardia farcinica diagnosed through DNA sequencing in a kidney transplantation patient. Clin Nephrol 2008; 70:542-545. [PMID: 19049715] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/27/2023] Open
Abstract
Nocardia is a rare gram-positive bacteria causing opportunistic infection, and belongs to the aerobic Actinomycetes group. As the mortality in the immunocompromised patients with nocardiosis is high, early diagnosis and treatment is very important. However, clinical manifestations of infection caused by Nocardia are very variable and early diagnosis is limited by the difficulty in obtaining specimens and its isolation. Rapid diagnosis of Nocardia infection may allow for earlier effective therapy, thus improving patient outcome. We report a case of Nocardia farcinica diagnosed by DNA sequencing through blood culture in a renal transplant recipient with severe pneumonia and multiple brain abscesses.
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Doo EY, Shin JH, Kim JH, Song HY. Oesophageal strictures caused by the ingestion of corrosive agents: effectiveness of balloon dilatation in children. Clin Radiol 2008; 64:265-71. [PMID: 19185656 DOI: 10.1016/j.crad.2008.10.001] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2008] [Revised: 09/26/2008] [Accepted: 10/05/2008] [Indexed: 12/17/2022]
Abstract
AIM To evaluate the safety and clinical effectiveness of balloon dilatation in children for oesophageal strictures caused by the ingestion of corrosive agents. MATERIALS AND METHODS The study comprised 11 children (median age 6 years; range 1-14 years) with oesophageal strictures caused by corrosive agents, who underwent a total of 36 balloon dilatation sessions. The technical and clinical success, recurrence of dysphagia, complications, and primary and secondary patency rates were retrospectively evaluated. RESULTS Technical success was achieved in 91% of patients and in 97% of balloon dilatation sessions. Clinical success (defined as improved food intake and reduced dysphagia within 1 month of the first balloon dilatation session) was achieved in 64% of patients (7/11). During the mean 35-month follow-up period (range 1-89 months), 10 (91%) patients experienced recurrence. Oesophageal rupture (types 1 or 2) occurred in 45% of patients and in 31% of balloon dilatation sessions. Primary patency rates at 6 months and 1, 2, 3, 4, and 5 years were 36, 27, 14, 14, 14, and 14%, respectively. Secondary patency rates at 6 months and 1, 2, 3, 4, and 5 years were 82, 82, 82, 56, 42, and 42%, respectively. The secondary patency rate was higher than the primary patency rate (p<0.05). CONCLUSION The present study examined oesophageal balloon dilatation for paediatric oesophageal strictures caused by the ingestion of corrosive agents. Although the technical success rate was high and there were no deaths, the clinical success rate was low owing to a high recurrence rate. However, repeated balloon dilatations resulted in an acceptable secondary patency rate.
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Ohshima S, Shin JH, Yuasa K, Nishiyama A, Kira J, Okada T, Takeda S. Transduction efficiency and immune response associated with the administration of AAV8 vector into dog skeletal muscle. Mol Ther 2008; 17:73-80. [PMID: 18941441 DOI: 10.1038/mt.2008.225] [Citation(s) in RCA: 71] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
Recombinant adeno-associated virus (rAAV)-mediated gene transfer is an attractive approach to the treatment of Duchenne muscular dystrophy (DMD). We investigated the muscle transduction profiles and immune responses associated with the administration of rAAV2 and rAAV8 in normal and canine X-linked muscular dystrophy in Japan (CXMD(J)) dogs. rAAV2 or rAAV8 encoding the lacZ gene was injected into the skeletal muscles of normal dogs. Two weeks after the injection, we detected a larger number of beta-galactosidase-positive fibers in rAAV8-transduced canine skeletal muscle than in rAAV2-transduced muscle. Although immunohistochemical analysis using anti-CD4 and anti-CD8 antibodies revealed less T-cell response to rAAV8 than to rAAV2, beta-galactosidase expression in rAAV8-injected muscle lasted for <4 weeks with intramuscular transduction. Canine bone marrow-derived dendritic cells (DCs) were activated by both rAAV2 and rAAV8, implying that innate immunity might be involved in both cases. Intravenous administration of rAAV8-lacZ into the hind limb in normal dogs and rAAV8-microdystrophin into the hind limb in CXMD(J) dogs resulted in improved transgene expression in the skeletal muscles lasting over a period of 8 weeks, but with a declining trend. The limb perfusion transduction protocol with adequate immune modulation would further enhance the rAAV8-mediated transduction strategy and lead to therapeutic benefits in DMD gene therapy.
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Lee KE, Shin JH, Song HY, Kim SB, Kim KR, Kim JH. Management of airway involvement of oesophageal cancer using covered retrievable nitinol stents. Clin Radiol 2008; 64:133-41. [PMID: 19103342 DOI: 10.1016/j.crad.2008.08.001] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2008] [Revised: 07/18/2008] [Accepted: 08/01/2008] [Indexed: 10/21/2022]
Abstract
AIM To assess the efficacy and safety of covered retrievable nitinol stents in oesophageal cancer patients with airway involvement. MATERIALS AND METHODS Under fluoroscopic guidance, covered retrievable nitinol airway stents were placed in 23 oesophageal cancer patients with airway stricture and/or oesophagorespiratory fistula (ERF) over a long period of 12 years. Six patients only had aspiration by ERF and three patients had both airway stricture and asymptomatic ERF. Technical aspects, dyspnoea improvement, and/or resolution of ERF symptoms, complications, reinterventions, and survival data were evaluated. RESULTS A total of 27 airway stents (14 tracheal, 11 bronchial, and two hinged) were placed successfully in 23 patients with airway stricture or ERF. Dyspnoea score decreased significantly after stent placement (p<0.001). ERF were sealed off in all nine patients. Complications included stent migration or expectoration (n=4), haemoptysis (n=2), sputum retention (n=7), and tumour overgrowth (n=1). All three migrated stents were easily removed. Twenty-one patients died, with the median survival period of 76 days (range 2-197 days). CONCLUSION Placement of covered retrievable expandable nitinol stents was safe and effective for the palliative treatment of airway strictures and/or ERF, with a reasonable range of complications, in patients with advanced oesophageal cancer.
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Kim K, Rhee JE, Lee CC, Kim KS, Shin JH, Kwak MJ, Kim JH, Suh GJ, Hahn SK, Singer AJ. Impact of helical computed tomography in clinically evident appendicitis. Emerg Med J 2008; 25:477-81. [PMID: 18660392 DOI: 10.1136/emj.2006.044552] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
OBJECTIVES To determine the utility of multidetector computed tomography (MDCT) in patients with clinically evident acute appendicitis and to compare the test characteristics of overall clinical impression, Alvarado scores, and MDCT in suspected appendicitis. METHODS A prospective observational cohort study was conducted in two urban emergency departments (ED). Consecutive patients with suspected acute appendicitis were clinically evaluated by an emergency physician who was asked to determine whether appendicitis was clinically evident or not. Elements of the Alvarado scores were collected and all patients then underwent MDCT and a decision to operate, observe, or discharge the patients was made by a surgeon. The final diagnosis was based on surgical pathology or clinical follow-up. The test characteristics of clinical impression, Alvarado scores and MDCT were then calculated and the rates at which acute appendicitis was falsely diagnosed based on clinical impression and MDCT were compared using McNemar's test. RESULTS Of 157 study patients, 71 were considered to have clinically evident appendicitis before MDCT and 91 had findings of acute appendicitis on MDCT. 19 of the 71 patients with clinically evident appendicitis did not have appendicitis. 14 of 52 patients with an Alvarado score > or = 8 also did not have appendicitis. Three of 91 patients with acute appendicitis based on MDCT did not have appendicitis. The specificities of clinical impression and Alvarado score > or = 8 were 71.6% and 79.1%, respectively, and these were significantly lower than that of MDCT (95.5%, p<0.05). CONCLUSION The performance of abdominal MDCT in patients with a high degree of clinical suspicion for acute appendicitis reduces the number of false positives and has the potential to reduce negative appendectomies.
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Nishiyama A, Ampong BN, Ohshima S, Shin JH, Nakai H, Imamura M, Miyagoe-Suzuki Y, Okada T, Takeda S. Recombinant adeno-associated virus type 8-mediated extensive therapeutic gene delivery into skeletal muscle of alpha-sarcoglycan-deficient mice. Hum Gene Ther 2008; 19:719-30. [PMID: 18578595 DOI: 10.1089/hum.2007.184] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
Autosomal recessive limb-girdle muscular dystrophy type 2D (LGMD 2D) is caused by mutations in the alpha-sarcoglycan gene (alpha-SG). The absence of alpha-SG results in the loss of the SG complex at the sarcolemma and compromises the integrity of the sarcolemma. To establish a method for recombinant adeno-associated virus (rAAV)-mediated alpha-SG gene therapy into alpha-SG-deficient muscle, we constructed rAAV serotypes 2 and 8 expressing the human alpha-SG gene under the control of the ubiquitous cytomegalovirus promoter (rAAV2-alpha-SG and rAAV8-alpha-SG). We compared the transduction profiles and evaluated the therapeutic effects of a single intramuscular injection of rAAVs into alpha-SG-deficient (Sgca(-/-)) mice. Four weeks after rAAV2 injection into the tibialis anterior (TA) muscle of 10-day-old Sgca(-/-) mice, transduction of the alpha-SG gene was localized to a limited area of the TA muscle. On the other hand, rAAV8-mediated alpha-SG expression was widely distributed in the hind limb muscle, and persisted for 7 months without inducing cytotoxic and immunological reactions, with a reversal of the muscle pathology and improvement in the contractile force of the Sgca(-/-) muscle. This extensive rAAV8-mediated alpha-SG transduction in LGMD 2D model animals paves the way for future clinical application.
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Lee HS, Song HJ, Hong WK, Shin JH, Choi GS. Pseudoxanthoma elasticum-like papillary dermal elastolysis with solar elastosis. J Eur Acad Dermatol Venereol 2008; 22:368-9. [DOI: 10.1111/j.1468-3083.2007.02318.x] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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Yang ZQ, Shin JH, Song HY, Kwon JH, Kim JW, Kim KR, Kim JH. Fluoroscopically guided percutaneous jejunostomy: outcomes in 25 consecutive patients. Clin Radiol 2007; 62:1061-5; discussion 1066-8. [PMID: 17920864 DOI: 10.1016/j.crad.2007.02.023] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2006] [Revised: 01/17/2007] [Accepted: 02/24/2007] [Indexed: 01/28/2023]
Abstract
AIM To assess the feasibility and safety of fluoroscopically guided percutaneous jejunostomy. MATERIAL AND METHODS Between May 1999 and August 2006 percutaneous jejunostomy was attempted in 25 patients. A 5 F vascular catheter (n=20) or a 7.5 F multifunctional coil catheter (n=5) was used to insufflate the jejunum. The distended jejunum was punctured using a 17 G needle (n=19) or a 21 G Chiba needle (n=6) with the inserted catheter as a target. A 12 or 14 F loop feeding tube was inserted after serial dilations. The technical success, complications, 30-day mortality, and in-dwelling period of the feeding tube placement were evaluated. RESULTS The technical success rate was 92% (23/25). Technical failures (n=2) resulted from the inability to insufflate the jejunum secondary to failure to pass the catheter through a malignant stricture at the oesophagojejunostomy site and thus subsequent puncture of the undistended jejunum failed, or failure to introduce the Neff catheter into the jejunum. Pericatheter leakage with pneumoperitoneum was a complication in three patients (12%) and was treated conservatively. The 30-day mortality was 13% (3/23); however, there was no evidence that these deaths were attributed to the procedure. Except for four patients who were lost to follow-up and two failed cases, 15 of the 19 jejunostomy catheters were removed because of patient death (n=12) or completion of treatment (n=3), with a mean and median in-dwelling period of 231 and 87 days, respectively. CONCLUSIONS Fluoroscopically guided percutaneous jejunostomy is a feasible procedure with a high technical success and a low complication rate. In addition to a 17 G needle, a 21 G needle can safely be used to puncture the jejunum.
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Shin JH, Song HK, Lee JH, Kim WK, Chu MK. Paroxysmal stabbing headache in the multiple dermatomes of the head and neck: a variant of primary stabbing headache or occipital neuralgia? Cephalalgia 2007; 27:1101-8. [PMID: 17725653 DOI: 10.1111/j.1468-2982.2007.01395.x] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
A paroxysmal stabbing or icepick-like headache in the multiple nerve dermatomes, especially involving both trigeminal and cervical nerves, has not been fully explained or classified by the International Classification of Headache Disorder, 2(nd) Edition (ICHD-II). Of patients with acute-onset paroxysmal stabbing headache who had visited the Hallym University Medical Center during the last four years, 28 subjects with a repeated stabbing headache involving multiple dermatomes at the initial presentation or during the course were prospectively enrolled. All patients were neurologically and otologically symptom free. A coincidental involvement of both trigeminal and cervical nerve dermatomes included seven cases. Six cases involved initially the trigeminal and then cervical nerve dermatomes. Five cases showed an involvement of the cervical and then trigeminal nerve dermatomes. The remaining patients involved multiple cervical nerve branches (the lesser occipital, greater occipital and greater auricular). Pain lasted very shortly and a previous history of headache with the same nature was reported in 13 cases. Preceding symptom of an infection and physical and/or mental stress were manifested in seven and six subjects, respectively. All patients showed a self-limited benign course and completely recovered within a few hours to 30 days. Interestingly, a seasonal gradient in occurrence of a stabbing headache was found in this study. A paroxysmal stabbing headache manifested on multiple dermatomes can be explained by the characteristics of pain referral, and may be considered to be a variant of primary stabbing headache or occipital neuralgia.
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Abstract
The limb-girdle muscular dystrophy type 2A (LGMD2A) is a recessively inherited disease caused by a mutation of the calpain 3 gene (CAPN3), and is considered one of the most prevalent subtypes of limb-girdle muscular dystrophy (LGMD). In this study, we aimed to identify CAPN3 mutations and to characterize the phenotype of Korean patients with LGMD2A. Among 35 patients with LGMD, four patients, who showed calpain 3 deficiency on western blot analysis, were analyzed in this study. Total RNA extracted from frozen muscle tissue was amplified by reverse transcriptase polymerase chain reaction (RT-PCR) using six primer pairs covering all coding sequences of CAPN3, and direct sequencing was performed. Clinical and pathological features of the patients were also reviewed. We found four different mutations in five alleles from three patients. Of the pathogenic mutations identified, two were novel (c.2125T>C and c.2355-2357delTTC), and the others had been reported elsewhere (c.440G>C, c.1076C>T). All patients showed a high CK level with predominant proximal leg weakness, and the onset was in their childhood except for one patient. Among two novel CAPN3 mutations, one was a missense mutation (c.2125T>C [p.709Ser>Pro]), and the other was a small in-frame deletion causing omission of a single amino acid (c.2355-2357delTTC [p.786delPhe]). The clinical features of our patients were generally compatible with the characteristics of LGMD2A patients described in the previous studies.
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Song HY, Kim JH, Shin JH, Kim HC, Yu CS, Kim JC, Kang SG, Yoon CJ, Lee JY, Koo JH, Lee KH, Kim JK, Kim DH, Shin TB, Jung GS, Han YM. A dual-design expandable colorectal stent for malignant colorectal obstruction: results of a multicenter study. Endoscopy 2007; 39:448-54. [PMID: 17516352 DOI: 10.1055/s-2007-966270] [Citation(s) in RCA: 53] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
BACKGROUND AND STUDY AIMS It is known that metal stent placement is safe, easy, and effective for the treatment of malignant colorectal obstruction, but these stents are associated with delayed complications of tumor ingrowth and stent migration. The aim of this study was to prospectively investigate the technical feasibility, clinical effectiveness, and safety of a dual-design colorectal stent (consisting of an outer stent and an inner bare nitinol stent) in patients with malignant colorectal obstruction. PATIENTS AND METHODS Placement of the dual stent using a 4.5-mm stent delivery system was attempted in 151 patients with malignant colorectal obstruction, either before surgery (n = 50) or for palliation (n = 101). Multivariate logistic regression analysis was used to identify risk factors associated with complications. RESULTS Stent placement was technically successful in 145/151 patients (96%). Of the patients who had a technically successful placement, bowel obstruction resolved within 2 days after stent placement in 48/50 (96%) of the patients in the bridge-to-surgery group and in 87/95 (92%) of the patients in the palliative group. Perforation occurred in 16 patients, incomplete stent expansion in eight patients, stent migration in four patients, tumor overgrowth in five patients, severe rectal pain in five patients, and bleeding in eight patients. Complete obstruction was the only significant risk factor for perforation (odds ratio 6.88, 95% CI 2.04-23.17, P = 0.002). In the palliative group, the median survival was 152.0 days and the mean survival was 263.8 days. CONCLUSIONS The dual stent with a 4.5-mm stent delivery system is easy to insert, safe, and reasonably effective for the palliative treatment of malignant colorectal obstruction. However, a great deal of care is needed in its deployment because of the high rate of perforation.
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Shin JH, Takeda S. [Therapeutic strategy for muscular dystrophies]. BRAIN AND NERVE = SHINKEI KENKYU NO SHINPO 2007; 59:415-24. [PMID: 17447528] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/15/2023]
Abstract
A successful cure for muscular dystrophies has yet to be demonstrated, but we could notice spectacular progress for the past few years. Advances have been made in methods of delivering foreign genes into muscle cells, either as naked plasmid DNA or via viral vectors. Among the virus-based methods, results with adeno-associated viral vectors have been the most promising. Systemic administration of anti-sense oligonucleotides has shown incredible success in inducing dystrophin expression and ameliorating muscle pathology via exon skipping in canine models of muscular dystrophy. Biochemical and functional rescue of dystrophic muscle has also been demonstrated with the transplantation of normal or genetically modified myogenic stem cells, as well as with a number of pharmacological approaches in animal models. Here we review the current researches on the treatment of muscular dystrophies and clinical trials on Duchenne muscular dystrophy.
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Shin JH, Lee EJ, Lee HR, Ryu SM, Kim HR, Chang CL, Kim YJ, Lee JN. Prevalence of non-tuberculous mycobacteria in a hospital environment. J Hosp Infect 2007; 65:143-8. [PMID: 17174440 DOI: 10.1016/j.jhin.2006.10.004] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2006] [Accepted: 10/12/2006] [Indexed: 11/27/2022]
Abstract
In recent years, non-tuberculous mycobacteria (NTM) have emerged as an important cause of opportunistic nosocomial infections but there is little known about the isolation and identification of NTM in Korea. The aim of this study was to assess the prevalence of NTM in the hospital environment and identify the species. A total of 150 samples were collected from different parts of the hospital. NTM were isolated and identified by restriction fragment length polymorphism analysis of the gene encoding rpoB and partial sequencing analysis of hsp65 and rpoB. In this study, 60 strains of NTM were isolated from 50 of the 150 samples. Half of the tap water samples (50 of 100) were positive for mycobacteria. An estimated 73.3% of the isolates were saprophytic, 21.7% were potentially pathogenic and 5% were unidentified. The presence of NTM in hospital tap water is not uncommon. Such water isolates might cause true nosocomial infection in immunocompromised patients, in addition to the risk of false-positive culture results.
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Shin JH, Choi HY, Lee SN, Kim YJ. Microinvasive ductal carcinoma arising within a fibroadenoma: A case report. Acta Radiol 2006; 47:643-5. [PMID: 16950696 DOI: 10.1080/02841850600698838] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Abstract
Fibroadenomas are among the most common benign breast tumors in which carcinomas rarely develop. We report the imaging findings of a microinvasive ductal carcinoma arising within a fibroadenoma in a 51-year-old woman. This mass showed coarse heterogeneous microcalcifications within a circumscribed mass on mammography, a heterogeneous hypoechoic mass on ultrasound, and an early enhancing mass on magnetic resonance imaging. Although a fibroadenoma in an older woman appears benign-looking, the presence of any unusual signs should raise concerns about malignancy.
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167
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Kim JW, Shin JH, Ko GY, Yoon HG, Song HY, Sung KB. A case of successful embolotherapy for gastric ulcer bleeding from the intercostal artery after oesophagectomy and gastric reconstruction. Br J Radiol 2006; 79:e96-8. [PMID: 16940369 DOI: 10.1259/bjr/61547332] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
Abstract
We report a successful treatment with coil embolisation of an intercostal artery for ulcer bleeding in a gastric tube in a 70-year-old man who underwent a total oesophagectomy and gastric tube reconstruction for oesophageal cancer. This case teaches us to search aberrant feeding vessels when active bleeding is suspected in reconstructed gastric tube in the patient with oesophagectomy and oesophagogastrostomy.
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Kim JH, Kim YH, Shin JH, Sung DJ, Shim TS, Cho SB, OH YM, Chung KB, Song HY, Cha SH, Park HS, Um JW. Deep tracheal laceration after balloon dilation for benign tracheobronchial stenosis: case reports of two patients. Br J Radiol 2006; 79:529-35. [PMID: 16714758 DOI: 10.1259/bjr/17839516] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
We report two cases of deep tracheal laceration in female patients after balloon dilation for benign tracheobronchial stenosis. Immediate post-procedure bronchoscopy and CT including 3D reconstructions showed deep lacerations in the posterior tracheal wall. Clinically, the patients' dyspnoea subsided and there has been no recurrence during follow-up after balloon dilation. On the follow-up 3D-reconstructed CT scans obtained 2 months and 8 months following balloon dilation, respectively, the lacerations had healed completely and there was considerable improvement in lumen size.
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Ko K, Han BK, Shin JH, Choe YH, Chung HW, Lee EH, Choi SJ. The axillopectoral muscle seen on mammography. Clin Radiol 2006; 61:625-9. [PMID: 16784950 DOI: 10.1016/j.crad.2006.03.015] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2006] [Accepted: 03/06/2006] [Indexed: 11/30/2022]
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Shin JH, Han BK, Ko K, Choe YH, Oh YL. Value of repeat ultrasound-guided fine-needle aspiration in nodules with benign cytological diagnosis. Acta Radiol 2006; 47:469-73. [PMID: 16796308 DOI: 10.1080/02841850600635921] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Abstract
PURPOSE To assess the value of repeat ultrasound-guided fine-needle aspiration (US-FNA) in nodules with benign cytological diagnosis. MATERIAL AND METHODS One-hundred-and-eighty-seven patients undergoing repeat US-FNA were included after a benign cytological diagnosis had been made by the initial US-FNA. They were divided into a re-aspiration group, who underwent repeat US-FNA within 6 months for a discordant pathological and clinico-radiological result, and a follow-up aspiration group, who underwent repeat US-FNA after 6 months without any clinical or radiological suspicion. The cancer rate in each group and the US findings of the later-diagnosed malignant nodules were assessed. RESULTS Nine malignancies were verified in the 187 cases (4.8%) by repeat US-FNA or surgery. In 44 patients in the re-aspiration group, 6 malignancies were identified (13.6%), compared with 3 malignancies in the 143 patients in the follow-up aspiration group (2.1%) (P<0.05). The later-diagnosed malignant nodules were an average of 1.0 cm in diameter; 66.7% were round; 66.7% were circumscribed; 100% were solid; 88.9% were hypoechoic; and 55.6% contained calcifications on US. CONCLUSION The follow-up of nodules with benign cytological diagnosis without clinicoradiological suspicion of malignancy is warranted using imaging surveillance rather than repeated US-FNA.
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Nam DH, Shin JH, Song HY, Jung GS, Han YM. Malignant esophageal-tracheobronchial strictures: parallel placement of covered retrievable expandable nitinol stents. Acta Radiol 2006; 47:3-9. [PMID: 16498926 DOI: 10.1080/02841850500334989] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
PURPOSE To assess the safety and clinical effectiveness of the parallel placement of covered retrievable expandable metallic stents in the palliative treatment of malignant esophageal and tracheobronchial strictures. MATERIAL AND METHODS Under fluoroscopic guidance, parallel stents were placed in 12 symptomatic patients with both malignant esophageal and tracheobronchial strictures. Seven of these 12 patients also had an esophagorespiratory fistula (ERF) and one patient had an esophagocutaneous fistula. Technical success, clinical improvement, complications, and survival rates were evaluated. RESULTS A total of 28 esophageal and airway stents were successfully placed. The grade of dysphagia and dyspnea score significantly decreased after stent placement (P=0.002 and 0.003, respectively). ERF and esophagocutaneous fistula were sealed off in all eight patients after esophageal stent placement; however, the esophagocutaneous fistula reopened 1 month later. Complications included stent migration or expectoration (n=3), tracheal compression by the esophageal stent (n=3), new fistula development due to covering membrane degradation of the esophageal stent (n=1), and symptomatic sputum retention (n=1). Stent removal was easily performed for two stents; one migrated stent and the other with covering membrane degradation. All 12 patients died within the mean survival period of 72.50 days (range 7-375 days). CONCLUSION Parallel placement of covered retrievable expandable metallic stents is safe and effective for the palliative treatment of malignant esophageal and tracheobronchial strictures.
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Shin JH, Kim H, Lim D, Jeon M, Han BK, Park TS, Kim JK, Lillehoj HS, Cho BW, Han JY. Analysis of chicken embryonic gonad expressed sequenced tags. Anim Genet 2006; 37:85-6. [PMID: 16441308 DOI: 10.1111/j.1365-2052.2006.01411.x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Cho D, Lee JS, Yazer MH, Song JW, Shin MG, Shin JH, Suh SP, Jeon MJ, Kim JY, Park JT, Ryang DW. Chimerism and mosaicism are important causes of ABO phenotype and genotype discrepancies. Immunohematology 2006; 22:183-7. [PMID: 17430077] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/14/2023]
Abstract
Discrepancies between blood group genotype and RBC phenotype are important to recognize when implementing DNA-based blood grouping techniques. This report describes two such cases involving the ABO blood group in the Korean population. Propositus #1 was a 22-year-old healthy man undergoing pretransfusion testing for minor surgery. Propositus #2 was a 23- year-old male blood donor. RBCs from both propositi were determined to be group AB and demonstrated unusual agglutination patterns on forward typing, which were inconsistent with their ABO genotype determined by allele-specific (AS) PCR. RBCs from propositus #1 demonstrated mixed field agglutination with both anti-A and -B, while RBCs from propositus #2 demonstrated mixed field only with anti-A reagents. Both had B/O genotypes by AS-PCR. Cloning and sequencing of ABO exons 6 and 7 revealed three alleles in both propositi: propositus #1: A102/B101/O04; propositus #2: A102/B101/O01. A panel of nine short-tandem repeat (STR) loci was tested on DNA extracted from blood, buccal mucosal cells, and hair from the propositi and on DNA isolated from their parents' blood. In all tissues tested from propositus #1, three loci demonstrated a double paternal and a single maternal DNA contribution, indicating that he was a chimera or a mosaic; in those from propositus # 2, one STR locus demonstrated a double paternal DNA contribution, indicating that he was a tetragametic chimera. Chimerism and mosaicism are uncommon but important causes of ABO genotype and phenotype discrepancies. The evaluation of patients and donors with unusual or unexpected serology in pretransfusion testing and consensus ABO alleles may include the evaluation of STR loci to detect these phenomena.
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Cho D, Shin MG, Yazer MH, Kee SJ, Shin JH, Suh SP, Jeon MJ, Song JW, Ki CS, Ryang DW. The genetic and phenotypic basis of blood group A subtypes in Koreans. Transfus Med 2005; 15:329-34. [PMID: 16101812 DOI: 10.1111/j.0958-7578.2005.00598.x] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
A serological and genetic study of Korean blood donors with phenotypic group A subtypes was performed. There were 176 donors with phenotypic A subtypes identified. Exons 6 and 7 from 57 representative donors were sequenced. The A(var) allele (784 G > A) was cloned and sequenced, and a family study demonstrating its inheritance and unusual serological characteristics was performed. The A102 allele was the most frequently identified allele in phenotypically A2 (58%, 11/19) and A2B (68%, 17/25) donors. Anti-A1 was rarely present amongst A2 and A2B donors. The family study revealed that the A(var) allele was expressed as phenotype A(weak)B in A(var)/B heterozygote members, but as phenotype O in A(var)/O heterozygotes. The most frequent allele in Korean donors with the A2 phenotype differs from its Caucasian counterpart, as does the frequency of anti-A1. The A(var) allele demonstrates allelic enhancement in A(var)/B heterozygotes.
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Yoon SZ, Shin JH, Hahn S, Oh AY, Kim HS, Kim SD, Kim CS. Usefulness of the carina as a radiographic landmark for central venous catheter placement in paediatric patients † †Presented, in part, at the 2005 Annual Meeting of European Society of Anaesthesiologists, Vienna, Austria. Br J Anaesth 2005; 95:514-7. [PMID: 16040638 DOI: 10.1093/bja/aei199] [Citation(s) in RCA: 56] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
BACKGROUND Several reports have proposed radiographic landmarks for the proper positioning of central venous catheters (CVC). The carina is one of the proposed landmarks in adults. Here, we evaluate the possibility of using the carina as a radiographic landmark for the identification of proper positioning of the CVC tip in paediatric patients. METHODS We studied 57 right internal jugular vein catheterizations in infants and children undergoing surgery for the treatment of congenital heart disease. After placing the CVC tip at the junction of the superior vena cava and the right atrium (SVC-RA junction) via intraoperative transoesophageal echocardiography, and by taking postoperative anterior-posterior chest radiographs, we measured the longitudinal distance from the carina to the SVC-RA junction, using the Picture Archiving and Communicating System. RESULTS The average distance between the carina and the SVC-RA junction was 1.5 cm (95% CI 1.3-1.8 cm). No catheter tip was above the carina. Although there was no particular relationship between this distance and the patient's age, height, or weight, the distance between the carina and the SVC-RA junction tended to be more variable in younger and smaller children. CONCLUSIONS The carina can be used as a radiographic landmark for the proper CVC tip placement in paediatric patients. If the tip of the CVC is not distal to the carina the chances are minute that it is in the right atrium.
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Han JY, Song KD, Shin JH, Han BK, Park TS, Park HJ, Kim JK, Lillehoj HS, Lim JM, Kim H. Identification and characterization of the peroxiredoxin gene family in chickens. Poult Sci 2005; 84:1432-8. [PMID: 16206565 DOI: 10.1093/ps/84.9.1432] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Peroxiredoxin (PRX) is a crucial antioxidant protein that protects against endogenously produced peroxides in prokaryotes to eukaryotes. To date, 6 different isoforms have been identified in mammals. In this study, we describe the first members of the PRX protein family to be characterized in Chicken. Through bioinformatics analysis, we observed that at least 4 different classes of PRX protein have been evolutionarily conserved in chickens. Furthermore, in vitro functional assays of the candidate chicken PRX proteins demonstrated that they had levels of antioxidant activity similar to those of the mammalian enzymes. The expression patterns of the PRX transcript in several chicken tissues were not tissue specific, suggesting that they might play an essential role as a housekeeping gene in all tissues to protect against oxidative damage. In conclusion, the sequences of the putative members of this functional gene family in chickens could be effectively retrieved in silico through bioinformatics analysis, and the functionality of their gene products evaluated by in vitro comparative assay.
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Shin JH, Kim H, Song KD, Han BK, Park TS, Kim DK, Han JY. A set of testis-specific novel genes collected from a collection of Korean Native Chicken ESTs. Anim Genet 2005; 36:346-8. [PMID: 16026346 DOI: 10.1111/j.1365-2052.2005.01268.x] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
We report a set of testis-specific novel genes by comparing the The Institute for Genomic Research (TIGR) chicken gene index with the 13,132 expressed sequence tag (EST) collection from Korean Native Chicken (KNC). A total of 553 novel transcripts have resulted after comparison of our EST contigs and singlets against the chicken gene index and chicken genome sequences. Interestingly, 76% of the new genes were from testis-specific EST contigs or singlet and analysis of exon/intron structure showed that a significant number of the contigs have intronless coding regions. A large portion of the testis-specific transcripts have intronless coding region indicating that the testis-specific expression pattern is related to a group of single exon genes in the chicken. The chicken EST data that are described in this paper have been submitted to the NCBI dbEST under accession numbers CO759017-CO764274, CO765331-CO768903 and CO769672-CO773972.
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Lee JH, Shin JH, Park KP, Kim IJ, Kim CM, Lim JG, Choi YC, Kim DS. Phenotypic variability in Kennedy's disease: implication of the early diagnostic features. Acta Neurol Scand 2005; 112:57-63. [PMID: 15932358 DOI: 10.1111/j.1600-0404.2005.00428.x] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
OBJECTIVES The clinical diagnosis of Kennedy's disease (KD) is not easy when the typical manifestations are lacking, especially in early stage of the disease. In our study, we tried to identify the relative frequency of common clinical features and early symptoms in KD. METHOD Eighteen Korean patients with KD were included. Clinical findings were subdivided into two parts: the age at onset of each clinical symptoms and characteristic signs on investigations. With detailed clinical examinations, the serum creatine kinase (CK) level, electrophysiologic study and DNA analysis were performed and analyzed in detail. RESULTS In KD, the most consistent clinical findings at evaluations included perioral fasciculation with variable bulbar paresis, limb weakness with wasting, hyporeflexia, hand tremor, and elevated CK level. Some distinguishing features, such as X-linked family history, gynecomastia, and sensory abnormalities were absent in a half of cases. Frequent initial clinical findings include tremor (50%) and symptoms other than weakness, such as cramps and fatigability (33.3%). CONCLUSION We conclude that KD shows variable clinical and electrophysiological features. Our description on the onset and subsequent progression of each clinical finding might help to identify KD in early stage and avoid misdiagnosis.
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Abstract
Sequences of candidate chicken testis-specific genes were analysed in order to develop a resource for functional genomic studies of the testis and male germ cells. Tentative consensus sequences (TC) containing expressed sequence tags expressed in testis libraries were selected from the TIGR Gallus gallus Gene Index, resulting in 292 TC. The transcriptional expression of these genes were evaluated in several chicken tissues, including testis and ovary. One hundred ten of the 292 TC were expressed in a testis-specific manner. Annotation of the TC using the Gene Ontology database terms showed that the proportion of testis-specific TC that were classified as having catalytic activity (within the molecular function branch) was higher than the proportion of total chicken TC classified in the same way. Our results may facilitate the investigation of testis-specific genes and their functional analysis in the chicken, as well as in other avian species.
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Shin JH, Sang BI, Chung YC, Choung YK. Feasibility study on the removal of nitrous compounds with a hollow-fiber membrane biofilm reactor. WATER SCIENCE AND TECHNOLOGY : A JOURNAL OF THE INTERNATIONAL ASSOCIATION ON WATER POLLUTION RESEARCH 2005; 51:365-71. [PMID: 16003998] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
The objective of this study was to develop an integrated nitrogen treatment system using autotrophic organisms. A treatment system consists of an aerobic hollow-fiber membrane biofilm reactor (HfMBR) and anaerobic HfMBR. In the aerobic HfMBR, a mixture gas of air and O2 was supplied through the fibers for nitrification. Denitrification occurred in the anaerobic HfMBR using H2 as the electron donor. The treatment system was continuously operated for 190 days. NH4-N removal efficiencies ranging from 95% to 97% were achieved at NH4-N concentrations of influent ranging from 50 to 100 mg N/L. When glucose was added to the influent, the simultaneous nitrification and denitrification occurred in the aerobic HfMBR, and nitrogen removal rates were changed according to the COD/NH4-N ratio of influent. In the anaerobic HfMBR, autotrophic denitrification using H2 occurred and the removal rates achieved in this study were 23-58 mg N/m2 d. In this study, the achieved removal efficiency was lower than other study findings; however, the result suggested that this hybrid HfMBR system can be used effectively for nitrogen removal in oligotrophic water.
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Gardel ML, Shin JH, MacKintosh FC, Mahadevan L, Matsudaira PA, Weitz DA. Scaling of F-actin network rheology to probe single filament elasticity and dynamics. PHYSICAL REVIEW LETTERS 2004; 93:188102. [PMID: 15525211 DOI: 10.1103/physrevlett.93.188102] [Citation(s) in RCA: 92] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/30/2003] [Indexed: 05/24/2023]
Abstract
The linear and nonlinear viscoelastic response of networks of cross-linked and bundled cytoskeletal filaments demonstrates remarkable scaling with both frequency and applied prestress, which helps elucidate the origins of the viscoelasticity. The frequency dependence of the shear modulus reflects the underlying single-filament relaxation dynamics for 0.1-10 rad/sec. Moreover, the nonlinear strain stiffening of such networks exhibits a universal form as a function of prestress; this is quantitatively explained by the full force-extension relation of single semiflexible filaments.
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Lee JH, Shin JH, Kim DS, Jung DS, Park KH, Lee MK, Kim JY. A case of Lambert-Eaton myasthenic syndrome associated with atypical bronchopulmonary carcinoid tumor. J Korean Med Sci 2004; 19:753-5. [PMID: 15483357 PMCID: PMC2816344 DOI: 10.3346/jkms.2004.19.5.753] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/02/2022] Open
Abstract
The Lambert-Eaton myasthenic syndrome (LEMS) is typically recognized as a paraneoplastic syndrome associated with a small cell lung carcinoma (SCLC), whereas LEMS with other neuroendocrine lung tumors, including carcinoids or large cell lung carcinoma, are highly unusual. Here, we report a rare case of LEMS with atypical bronchopulmonary carcinoid tumor: a 65-yr-old man presented with progressive leg weakness and a diagnosis of LEMS was made by serial repetitive nerve stimulation test. Chest CT revealed a lung nodule with enlargement of paratracheal lymph nodes, and surgically resected lesion showed pathological features of atypical carcinoid tumor. We concluded that LEMS could be associated with rare pulmonary neuroendocrine tumor other than SCLC, which necessitates pathologic confirmation followed by aggressive treatment for optimal management in these rare cases.
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Cho D, Kim SH, Ki CS, Choi KL, Cho YG, Song JW, Shin JH, Suh SP, Yazer MH, Ryang DW. A novel Bvar allele (547 G>A) demonstrates differential expression depending on the co-inherited ABO allele. Vox Sang 2004; 87:187-9. [PMID: 15569071 DOI: 10.1111/j.1423-0410.2004.00575.x] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
BACKGROUND AND OBJECTIVES Genetic analysis of group B donors in Korea was performed. MATERIALS AND METHODS Exons 6 and 7 were sequenced in 12 phenotypically B3 donors 6 B3, 6 A1B3. RESULTS Consensus sequences all B3 and 2/6 A1B3 donors were present. Four A1B3 donors demonstrated a novel B allele, B(var), in the context of A101/ or A102/B(var) genotypes. Family studies based on an A1B3 donor with the B(var) allele and on another unrelated subject with identical genotype and phenotype revealed B(var)/O01 genotypes with full B-antigen expression. CONCLUSIONS B(var) allele is subject to differential expression, depending on the co-inherited ABO allele.
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184
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Shin JH, Gardel ML, Mahadevan L, Matsudaira P, Weitz DA. Relating microstructure to rheology of a bundled and cross-linked F-actin network in vitro. Proc Natl Acad Sci U S A 2004; 101:9636-41. [PMID: 15210969 PMCID: PMC470727 DOI: 10.1073/pnas.0308733101] [Citation(s) in RCA: 171] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2003] [Accepted: 05/12/2004] [Indexed: 11/18/2022] Open
Abstract
The organization of individual actin filaments into higher-order structures is controlled by actin-binding proteins (ABPs). Although the biological significance of the ABPs is well documented, little is known about how bundling and cross-linking quantitatively affect the microstructure and mechanical properties of actin networks. Here we quantify the effect of the ABP scruin on actin networks by using imaging techniques, cosedimentation assays, multiparticle tracking, and bulk rheology. We show how the structure of the actin network is modified as the scruin concentration is varied, and we correlate these structural changes to variations in the resultant network elasticity.
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185
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Gardel ML, Shin JH, MacKintosh FC, Mahadevan L, Matsudaira P, Weitz DA. Elastic behavior of cross-linked and bundled actin networks. Science 2004; 304:1301-5. [PMID: 15166374 DOI: 10.1126/science.1095087] [Citation(s) in RCA: 789] [Impact Index Per Article: 39.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
Networks of cross-linked and bundled actin filaments are ubiquitous in the cellular cytoskeleton, but their elasticity remains poorly understood. We show that these networks exhibit exceptional elastic behavior that reflects the mechanical properties of individual filaments. There are two distinct regimes of elasticity, one reflecting bending of single filaments and a second reflecting stretching of entropic fluctuations of filament length. The mechanical stiffness can vary by several decades with small changes in cross-link concentration, and can increase markedly upon application of external stress. We parameterize the full range of behavior in a state diagram and elucidate its origin with a robust model.
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186
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Valentine MT, Perlman ZE, Gardel ML, Shin JH, Matsudaira P, Mitchison TJ, Weitz DA. Colloid surface chemistry critically affects multiple particle tracking measurements of biomaterials. Biophys J 2004; 86:4004-14. [PMID: 15189896 PMCID: PMC1304301 DOI: 10.1529/biophysj.103.037812] [Citation(s) in RCA: 184] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2003] [Accepted: 02/23/2004] [Indexed: 11/18/2022] Open
Abstract
Characterization of the properties of complex biomaterials using microrheological techniques has the promise of providing fundamental insights into their biomechanical functions; however, precise interpretations of such measurements are hindered by inadequate characterization of the interactions between tracers and the networks they probe. We here show that colloid surface chemistry can profoundly affect multiple particle tracking measurements of networks of fibrin, entangled F-actin solutions, and networks of cross-linked F-actin. We present a simple protocol to render the surface of colloidal probe particles protein-resistant by grafting short amine-terminated methoxy-poly(ethylene glycol) to the surface of carboxylated microspheres. We demonstrate that these poly(ethylene glycol)-coated tracers adsorb significantly less protein than particles coated with bovine serum albumin or unmodified probe particles. We establish that varying particle surface chemistry selectively tunes the sensitivity of the particles to different physical properties of their microenvironments. Specifically, particles that are weakly bound to a heterogeneous network are sensitive to changes in network stiffness, whereas protein-resistant tracers measure changes in the viscosity of the fluid and in the network microstructure. We demonstrate experimentally that two-particle microrheology analysis significantly reduces differences arising from tracer surface chemistry, indicating that modifications of network properties near the particle do not introduce large-scale heterogeneities. Our results establish that controlling colloid-protein interactions is crucial to the successful application of multiple particle tracking techniques to reconstituted protein networks, cytoplasm, and cells.
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Kim SJ, Kim BC, Kim DC, Kim MK, Cho KH, Seo JJ, Shin JH. A fatal case of Vibrio vulnificus meningoencephalitis. Clin Microbiol Infect 2003; 9:568-71. [PMID: 12848737 DOI: 10.1046/j.1469-0691.2003.00680.x] [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: 12/17/2022]
Abstract
The objective of this paper is to report a rare case of Vibrio vulnificus presenting as meningoencephalitis without a wound infection. Vibrio vulnificus is capable of causing severe and often fatal infections in susceptible individuals. It commonly causes necrotizing wound infections, primary septicemia, and gastroenteritis. A 69-year-old man had meningoencephalitis with lesion on the red nucleus, substantia nigra, basal ganglia, and dentate nucleus as the initial clinical manifestation of a V. vulnificus infection. This is the first case of V. vulnificus infection in which MRI demonstrated the involvement of deep nuclei of the brain.
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188
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Shin DH, Park JH, Yoon KW, Shin JH, Kim SJ. Clostridium perfringens septicemia with thrombophlebitis of the portal vein. J Infect 2003; 46:253-5. [PMID: 12799155 DOI: 10.1053/jinf.2002.1123] [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: 11/11/2022]
Abstract
We report a case of patient with Clostridium perfringens septicemia and thrombophlebitis of the portal vein (pylephlebitis), probably secondary to an initially unrecognized gastric ulcer. The extension of the thrombosis from the superior mesenteric vein to the main portal vein on a repeat CT scan and subsequent partial resolution of the thrombus with antibiotic therapy alone, suggested that Clostridium perfringens bacteremia may have enhanced the formation of thrombus. The coexistence of Clostridium perfringens septicemia and pylephlebitis should prompt a search for intra-abdominal processes as the portal of entry of infection.
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Kim JH, Eun HW, Lee HK, Park SJ, Shin JH, Hwang JH, Goo DE, Choi DL. Renal perfusion abnormality. Coded harmonic angio US with contrast agent. Acta Radiol 2003. [PMID: 12694103 DOI: 10.1034/j.1600-0455.2003.00025.x] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
PURPOSE Coded harmonic angio (CHA) US is a recently developed technique that can depict the effects of contrast agents. The purpose of this study was to determine the role of this technique in depicting the enhancement patterns of various renal perfusion abnormalities compared with dynamic CT. MATERIAL AND METHODS During a 6-month period, various renal lesions including renal cell carcinoma (n=12), transitional cell carcinoma (n=5), acute pyelonephritis (n=5), and renal trauma (n=2) were evaluated with CHA US using a microbubble contrast agent. US images were obtained before contrast administration and with a bolus injection of 4 g of microbubble contrast agent (300 mg/ml) every 10 s for 1 min and every minute for 5 min. The contrast enhancement patterns of various renal masses were compared with dynamic CT. RESULTS Of 12 renal cell carcinomas, 9 (75%) showed heterogeneous enhancement and the remaining 3 (25%) showed homogeneous enhancement. Enhancement of more than adjacent renal parenchyma was seen 16-252 s after injection. The duration of enhancement was 13-208 s (mean, 80 s). All transitional cell carcinomas showed peripheral enhancement. Enhancement was seen 22-270 s after injection. The duration of enhancement was 191-238 s (mean, 291 s). Five patients with acute pyelonephritis and 2 with renal trauma showed focal perfusion defects not shown on the pre-contrast examinations. CONCLUSION CHA US with microbubble contrast agent is an effective US technique for the evaluation of both tumor vascularity and renal perfusion abnormality.
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Kim JH, Eun HW, Lee HK, Park SJ, Shin JH, Hwang JH, Goo DE, Choi DL. Renal perfusion abnormality. Coded harmonic angio US with contrast agent. Acta Radiol 2003; 44:166-71. [PMID: 12694103 DOI: 10.1080/j.1600-0455.2003.00025.x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/20/2023]
Abstract
PURPOSE Coded harmonic angio (CHA) US is a recently developed technique that can depict the effects of contrast agents. The purpose of this study was to determine the role of this technique in depicting the enhancement patterns of various renal perfusion abnormalities compared with dynamic CT. MATERIAL AND METHODS During a 6-month period, various renal lesions including renal cell carcinoma (n=12), transitional cell carcinoma (n=5), acute pyelonephritis (n=5), and renal trauma (n=2) were evaluated with CHA US using a microbubble contrast agent. US images were obtained before contrast administration and with a bolus injection of 4 g of microbubble contrast agent (300 mg/ml) every 10 s for 1 min and every minute for 5 min. The contrast enhancement patterns of various renal masses were compared with dynamic CT. RESULTS Of 12 renal cell carcinomas, 9 (75%) showed heterogeneous enhancement and the remaining 3 (25%) showed homogeneous enhancement. Enhancement of more than adjacent renal parenchyma was seen 16-252 s after injection. The duration of enhancement was 13-208 s (mean, 80 s). All transitional cell carcinomas showed peripheral enhancement. Enhancement was seen 22-270 s after injection. The duration of enhancement was 191-238 s (mean, 291 s). Five patients with acute pyelonephritis and 2 with renal trauma showed focal perfusion defects not shown on the pre-contrast examinations. CONCLUSION CHA US with microbubble contrast agent is an effective US technique for the evaluation of both tumor vascularity and renal perfusion abnormality.
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Yoon HJ, Shin JH, Yang SH, Chae DW, Kim H, Lee DS, Kim HL, Kim S, Lee JS, Kim YS. Association of the CD14 gene -159C polymorphism with progression of IgA nephropathy. J Med Genet 2003; 40:104-8. [PMID: 12566518 PMCID: PMC1735366 DOI: 10.1136/jmg.40.2.104] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
The risk factors associated with the progression of IgA nephropathy (IgAN), the most common form of glomerulonephritis, are unclear. It has been suggested that CD14 signalling in response to various microbes affects the natural history of chronic inflammatory conditions. It has been hypothesised that variants in the promoter region of the CD14 gene might alter the expression of CD14, and this in turn could influence the progressive nature of IgAN. PCR-RFLP was used to determine the polymorphism at the -159 site (T to C). The distribution of the CD14/-159 polymorphism was no different in patients with IgAN (n=216) compared to 171 healthy controls. After follow up for 86 months, it was found that an excess of the C genotype occurred in patients with progressive disease (p=0.03) and the risk of disease progression increased as the number of C alleles increased (p for trend = 0.002). The hazard ratio for progression in the patients with the CC genotype was 3.2 (p=0.025) compared with the patients possessing the TT genotype. After LPS stimulation, sCD14 was released more abundantly from the PBMCs of the TT subjects than from that of the CC subjects (p=0.006), even though mCD14 expression level was no different. In addition, the TT subjects released less IL-6 than the CC subjects after stimulation (p=0.0003). These results suggest that the CD14/-159 polymorphism is an important marker for the progression of IgAN and may modulate the level of the inflammatory responses.
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Lee SJ, Shin JH, Sung NJ, Kim JG, Hotchkiss JH. Effect of cooking on the formation of N-nitrosodimethylamine in Korean dried seafood products. FOOD ADDITIVES AND CONTAMINANTS 2003; 20:31-6. [PMID: 12519716 DOI: 10.1080/0265203021000014770] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
Only N-nitrosodimethylamine (NDMA) was detected when N-nitrosamines (NA) were analysed in seven dried seafood products, either uncooked or cooked. The cooking methods used were a briquet fire, a gas range, an electric oven, a microwave oven, a steam cooker and an electric coil cooker. The contents of NDMA ranged from 1.0 to 46.9 microgram kg(-1) in uncooked products. When these samples were cooked, regardless of the cooking method, the content of NDMA tended to increase, ranging from 1.1 to 630.5 microgram kg(-1). In general, indirect heating such as a steam cooker and a microwave oven, as compared with direct heating such as a gas range and a briquet fire, caused less increase in NDMA during cooking.
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Skerrett IM, Aronowitz J, Shin JH, Cymes G, Kasperek E, Cao FL, Nicholson BJ. Identification of amino acid residues lining the pore of a gap junction channel. J Cell Biol 2002; 159:349-60. [PMID: 12403817 PMCID: PMC2173043 DOI: 10.1083/jcb.200207060] [Citation(s) in RCA: 71] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2002] [Revised: 08/28/2002] [Accepted: 08/28/2002] [Indexed: 11/23/2022] Open
Abstract
Gap junctions represent a ubiquitous and integral part of multicellular organisms, providing the only conduit for direct exchange of nutrients, messengers and ions between neighboring cells. However, at the molecular level we have limited knowledge of their endogenous permeants and selectivity features. By probing the accessibility of systematically substituted cysteine residues to thiol blockers (a technique called SCAM), we have identified the pore-lining residues of a gap junction channel composed of Cx32. Analysis of 45 sites in perfused Xenopus oocyte pairs defined M3 as the major pore-lining helix, with M2 (open state) or M1 (closed state) also contributing to the wider cytoplasmic opening of the channel. Additional mapping of a close association between M3 and M4 allowed the helices of the low resolution map (Unger et al., 1999. Science. 283:1176-1180) to be tentatively assigned to the connexin transmembrane domains. Contrary to previous conceptions of the gap junction channel, the residues lining the pore are largely hydrophobic. This indicates that the selective permeabilities of this unique channel class may result from novel mechanisms, including complex van der Waals interactions of permeants with the pore wall, rather than mechanisms involving fixed charges or chelation chemistry as reported for other ion channels.
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194
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Yoon HJ, Kim H, Kim HL, Lee SG, Zheng SH, Shin JH, Lim CS, Kim S, Lee JS, Lee DS, Kim YS. Interdependent effect of angiotensin-converting enzyme and platelet-activating factor acetylhydrolase gene polymorphisms on the progression of immunoglobulin A nephropathy. Clin Genet 2002; 62:128-34. [PMID: 12220450 DOI: 10.1034/j.1399-0004.2002.620205.x] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
In order to investigate the interdependent action of the insertion/deletion polymorphism of the angiotensin-converting enzyme (ACE) gene and polymorphism in exon 11 (C1136-->T; Ala379Val) of the platelet-activating factor acetylhydrolase (PAF-AH) gene, which encodes a functional antagonist of PAF, on the progression of immunoglobulin A (IgA) nephropathy, we analysed both polymorphisms in patients with primary IgA nephropathy, who were followed-up for longer than 3 years. During the follow-up (87.3 +/- 50.0 months), the disease progressed in 38 of the 191 patients (19.9%). The D allele of the ACE gene in the absence of the T allele of the PAF-AH gene did not affect the prognosis [odds ratio (OR), 3.6; 95% confidence interval (CI), 0.8-16.4] and neither did the T allele in the absence of the D allele (OR, 3.0; 95% CI, 0.4-24.2). However, the presence of both was a significant prognostic factor (OR, 6.6; 95% CI, 1.4-31.3). After adjusting for other risk factors, the presence of both proved to be an independent risk factor (OR, 4.5; 95% CI, 1.6-12.7). These results suggest that the interdependent effects of ACE and PAF-AH polymorphisms on the progression of IgA nephropathy might be more important than the effect of the individual polymorphisms.
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Shin JH, Kim MJ, Cho S, Whang KK, Hahm JH. A case of giant congenital nevocytic nevus with neurotization and onset of vitiligo. J Eur Acad Dermatol Venereol 2002; 16:384-6. [PMID: 12224698 DOI: 10.1046/j.1468-3083.2002.00563.x] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
The authors report the case of a 21-year-old woman with a giant congenital nevocytic nevus (GCNN) who developed vitiligo at the age of 16 years on skin areas remote from the GCNN. This is the first reported case of GCNN developing neurotization combined with vitiliginous changes within the GCNN lesion. Treatment with PUVA achieved repigmentation of the vitiligo lesions, except for the hypochromic areas within the area of the nevus that were shielded from UVA radiation.
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Lee CK, Ahn MS, Lee EY, Shin JH, Cho YS, Ha HK, Yoo B, Moon HB. Acute abdominal pain in systemic lupus erythematosus: focus on lupus enteritis (gastrointestinal vasculitis). Ann Rheum Dis 2002; 61:547-50. [PMID: 12006332 PMCID: PMC1754133 DOI: 10.1136/ard.61.6.547] [Citation(s) in RCA: 143] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
OBJECTIVE To determine the causes of acute abdominal pain in systemic lupus erythematosus (SLE) and to compare the clinical and laboratory data, especially antiphospholipid antibodies and the SLE Disease Activity Index (SLEDAI), between lupus enteritis (gastrointestinal vasculitis) and acute abdominal pain without lupus enteritis in patients with SLE. METHODS A retrospective study was carried out for all patients admitted with SLE from 1993 to March 2001. The SLEDAI and laboratory data were collected at the time of diagnosis of SLE and at the time of acute abdominal pain. Lupus enteritis (gastrointestinal vasculitis) was diagnosed by clinical investigation and abdominal computed tomographic findings. RESULTS Chart review identified 175 patients (20 male, 155 female) who had been admitted with SLE. Of these patients, 38 (22%) presented with acute abdominal pain. Lupus enteritis was the most common cause of acute abdominal pain. Patients were divided into three groups: group 1: lupus enteritis (n=17), group 2: acute abdominal pain without lupus enteritis (n=21), and group 3: SLE without acute abdominal pain (n=137). There was no difference in age and sex among the three groups. Antiphospholipid, anti-RNP, anti-Sm, anti-Ro, and anti-La antibodies did not differ among the three groups. There was no difference in the SLEDAI at the time of diagnosis and at the time of acute abdominal pain between groups 1 and 2. Complement, erythrocyte sedimentation rate, C reactive protein, and anti-dsDNA measured at the time of acute abdominal pain did not differ between groups 1 and 2. A drop in the white blood cell count at the time of abdominal pain was more prominent in group 1 than group 2. In lupus enteritis, the jejunum and ileum were the sites most commonly affected. Rectal involvement was rare. Even though four patients relapsed, all the patients with lupus enteritis, including those who relapsed, responded well to corticosteroid. CONCLUSION Lupus enteritis is the most common cause of acute abdominal pain in SLE. All patients with lupus enteritis responded well to a high dose of a corticosteroid without surgical intervention. The SLEDAI and laboratory data, except leucopenia, do not correlate with the occurrence of lupus enteritis.
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Shin JH, Lee HK, Kim SY, Choi CG, Suh DC. Imaging of parapharyngeal space lesions: focus on the prestyloid compartment. AJR Am J Roentgenol 2001; 177:1465-70. [PMID: 11717108 DOI: 10.2214/ajr.177.6.1771465] [Citation(s) in RCA: 41] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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198
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Shin JH, Sung IY, Suh JH, Yang SO, Jeong YK, Lee JH, Hwang JC. Solitary fibrous tumor in the buccal space: MR findings with pathologic correlation. AJNR Am J Neuroradiol 2001; 22:1890-2. [PMID: 11733322 PMCID: PMC7973830] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/22/2023]
Abstract
We report MR findings in a case of a solitary fibrous tumor involving the buccal space in a middle-aged man. On MR images, most of the mass was isointense and hyperintense to the muscle on T1- and T2-weighted images, respectively, and showed homogeneously strong enhancement on contrast-enhanced T1-weighted images. The medial peripheral portion, which was isointense on T2-weighted images and showed less enhancement on contrast-enhanced T1-weighted images, corresponded to the hypocellular and collagenous sclerotic area on pathologic correlation.
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Shin JH, Bridgewater BM, Churchill DG, Parkin G. Synthesis and structural characterization of PHP[(C(5)Me(4))(2)], a monodentate chiral phosphine derived from intramolecular C-C coupling of tetramethylcyclopentadienyl groups: an evaluation of steric and electronic properties. Inorg Chem 2001; 40:5626-35. [PMID: 11599963 DOI: 10.1021/ic010443j] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The chiral monodentate phosphine PhP[(C(5)Me(4))(2)] is readily obtained by oxidation of the lithium complex Li(2)[PhP(C(5)Me(4))(2)] with I(2), which couples the two cyclopentadienyl groups to form a five-membered heterocyclic ring. The steric and electronic properties of PhP[(C(5)Me(4))(2)] have been evaluated by X-ray diffraction and IR spectroscopic studies on a variety of derivatives, including Ph[(C(5)Me(4))(2)]PE (E = S, Se), Cp*MCl(4)[P[(C(5)Me(4))(2)]Ph] (M = Mo, Ta), Ir[P[(C(5)Me(4))(2)]Ph](2)(CO)Cl, and CpFe(CO)[PhP[(C(5)Me(4))(2)]]Me. For comparison purposes, derivatives of the related phospholane ligand PhP[Me(2)C(4)H(6)] have also been investigated, including Ph[Me(2)C(4)H(6)]PS, Ir[Ph[Me(2)C(4)H(6)]](2)(CO)Cl, Ir[Ph[Me(2)C(4)H(6)]](2)(CO)Me, Ir[PPh[Me(2)C(4)H(6)]](COD)(Cl), and Pd[P[Me(2)C(4)H(6)]Ph][eta(2)-C(6)H(4)C(H)(Me)NMe(2)]Cl. The steric and electronic properties of PhP[(C(5)Me(4))(2)] are determined to be intermediate between those of PPh(2)Me and PPh(3). Thus, the crystallographic cone angles increase in the sequence PPh(2)Me (134.5 degrees) < PhP[(C(5)Me(4))(2)] (140.2 degrees) < PPh(3) (148.2 degrees), while the electron donating abilities decrease in the sequence PPh(2)Me > PhP[(C(5)Me(4))(2)] > PPh(3). Finally, PhP[(C(5)Me(4))(2)] has a smaller cone angle and is less electron donating than the structurally similar phosphine, PhP[Me(2)C(4)H(6)].
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Shin JH, Bridgewater BM, Churchill DG, Baik MH, Friesner RA, Parkin G. An experimental and computational analysis of the formation of the terminal nitrido complex (eta3-Cp*)2Mo(N)(N3) by elimination of N2 from Cp*2Mo(N3)2: the barrier to elimination is strongly influenced by the exo versus endo configuration of the azide ligand. J Am Chem Soc 2001; 123:10111-2. [PMID: 11592896 DOI: 10.1021/ja011416v] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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