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Abstract
Corneal neovascularization (NV) is a sight-threatening condition usually associated with inflammatory or infectious disorders of the ocular surface. It has been shown in the field of cancer angiogenesis research that a balance exists between angiogenic factors (such as fibroblast growth factor and vascular endothelial growth factor) and anti-angiogenic molecules (such as angiostatin, endostatin, or pigment epithelium derived factor) in the cornea. Several inflammatory, infectious, degenerative, and traumatic disorders are associated with corneal NV, in which the balance is tilted towards angiogenesis. The pathogenesis of corneal NV may be influenced by matrix metalloproteinases and other proteolytic enzymes. New medical and surgical treatments, including angiostatic steroids, nonsteroidal inflammatory agents, argon laser photocoagulation, and photodynamic therapy have been effective in animal models to inhibit corneal NV and transiently restore corneal "angiogenic privilege."
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Review |
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Scofield SR, Tobias CM, Rathjen JP, Chang JH, Lavelle DT, Michelmore RW, Staskawicz BJ. Molecular Basis of Gene-for-Gene Specificity in Bacterial Speck Disease of Tomato. Science 1996; 274:2063-5. [PMID: 8953034 DOI: 10.1126/science.274.5295.2063] [Citation(s) in RCA: 435] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Transient expression of the Pseudomonas syringae avirulence gene avrPto in plant cells resulted in a Pto-dependent necrosis. The AvrPto avirulence protein was observed to interact directly with the Pto resistance protein in the yeast two-hybrid system. Mutations in the Pto and avrPto genes which reduce in vivo activity had parallel effects on association in the two-hybrid assay. These data suggest that during infection the pathogen delivers AvrPto into the plant host cell and that resistance is specified by direct interaction of Pto with AvrPto.
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Chang JH, Vines E, Bertsch H, Fraker DL, Czerniecki BJ, Rosato EF, Lawton T, Conant EF, Orel SG, Schuchter L, Fox KR, Zieber N, Glick JH, Solin LJ. The impact of a multidisciplinary breast cancer center on recommendations for patient management: the University of Pennsylvania experience. Cancer 2001; 91:1231-7. [PMID: 11283921 DOI: 10.1002/1097-0142(20010401)91:7<1231::aid-cncr1123>3.0.co;2-k] [Citation(s) in RCA: 222] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
BACKGROUND Advances in the diagnosis and treatment of breast carcinoma have led to a multidisciplinary approach to management for patients with breast carcinoma. To assess the effect of this approach, the authors performed an evaluation for a cohort of patients examined in a multidisciplinary breast cancer center. METHODS An analysis was performed for the records of 75 consecutive women with 77 breast lesions examined in consultation in a multidisciplinary breast cancer center between January and June 1998. Each patient's case was evaluated by a panel consisting of a medical oncologist, surgical oncologist, radiation oncologist, pathologist, diagnostic radiologist, and, when indicated, plastic surgeon. A comprehensive history and physical examination was performed, and the relevant mammograms, pathology slides, and medical records were reviewed. Treatment recommendations made before this evaluation were compared with the consensus recommendations made by the panel. RESULTS For the 75 patients, the multidisciplinary panel disagreed with the treatment recommendations from the outside physicians in 32 cases (43%), and agreed in 41 cases (55%). Two patients (3%) had no treatment recommendation before consultation. For the 32 patients with a disagreement, the treatment recommendations were breast-conservation treatment instead of mastectomy (n = 13; 41%) or reexcision (n = 2; 6%); further workup instead of immediate definitive treatment (n = 10; 31%); treatment based on major change in diagnosis on pathology review (n = 3; 9%); addition of postmastectomy radiation treatment (n = 3; 9%); or addition of hormonal therapy (n = 1; 3%). CONCLUSIONS The multidisciplinary breast cancer evaluation program provided an integrated program in which individual patients were evaluated by a team of physicians and led to a change in treatment recommendation for 43% (32 of 75) of the patients examined. This multidisciplinary program provided important second opinions for many patients with breast carcinoma.
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Comparative Study |
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Cheuk W, Chan JK, Shek TW, Chang JH, Tsou MH, Yuen NW, Ng WF, Chan AC, Prat J. Inflammatory pseudotumor-like follicular dendritic cell tumor: a distinctive low-grade malignant intra-abdominal neoplasm with consistent Epstein-Barr virus association. Am J Surg Pathol 2001; 25:721-31. [PMID: 11395549 DOI: 10.1097/00000478-200106000-00003] [Citation(s) in RCA: 216] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Follicular dendritic cell (FDC) tumors are uncommon neoplasms that can involve lymph nodes or extranodal sites. They can exhibit a broad spectrum of histologic appearances and behavior, but the intra-abdominal ones usually pursue an aggressive course. The purpose of this study was to characterize a distinctive variant of FDC tumor morphologically mimicking inflammatory pseudotumor through analysis of the clinicopathologic features of 11 cases. The patients included 10 women and one man (age range, 19-61 years; median age, 40 years) who presented with abdominal discomfort or pain. Six patients had systemic symptoms such as marked weight loss, fever, or malaise. All tumors occurred in intra-abdominal sites: liver (n = 7), spleen (n = 3), and peripancreatic region (n = 1). Of the nine patients with follow-up data, six were alive and well, one developed recurrence at 9 years, and two had repeated recurrences over many years. Grossly, the tumors were usually solitary and fleshy, punctuated by areas of hemorrhage and necrosis. Histologically, in a background of abundant lymphocytes and plasma cells were dispersed spindle or ovoid cells with vesicular nuclei and distinct nucleoli. The degree of nuclear atypia was variable, and some nuclei could be grotesque or resemble Reed-Sternberg cells. Focally, spindle cell fascicles could be formed. The atypical cells were immunoreactive for FDC markers such as CD21/CD35, CD23, and CNA.42. In situ hybridization for Epstein-Barr virus (EBV)-encoded RNA was positive in all cases, remarkably highlighting the spindle cells and their atypia. EBV-latent membrane protein-1 was expressed commonly, albeit often focally and weakly. Therefore, inflammatory pseudotumor-like FDC tumor represents a distinctive variant of FDC tumor that differs from conventional FDC tumor in the following aspects: marked female predominance; selective localization in intra-abdominal sites, especially the liver and spleen; frequent presence of systemic symptoms; indolent behavior despite an intra-abdominal location; dispersed distribution of tumor cells and prominent lymphoplasmacytic infiltration; and consistent association with EBV.
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Chang JH, Gill S, Settleman J, Parsons SJ. c-Src regulates the simultaneous rearrangement of actin cytoskeleton, p190RhoGAP, and p120RasGAP following epidermal growth factor stimulation. J Cell Biol 1995; 130:355-68. [PMID: 7542246 PMCID: PMC2199934 DOI: 10.1083/jcb.130.2.355] [Citation(s) in RCA: 211] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023] Open
Abstract
Analysis of C3H10T1/2 murine fibroblasts overexpressing wild type and dominant negative variants of c-Src has demonstrated a requirement for c-Src in EGF-induced mitogenesis. Correlating with the ability of c-Src variants to potentiate or inhibit EGF-dependent DNA synthesis is the phosphotyrosine content of multiple cellular proteins, including p190-RhoGAP, a protein thought to regulate growth factor-induced actin cytoskeleton remodeling by modulating the activity of the small GTP binding protein, Rho. Because the in vivo phosphotyrosine content of p190 varies with the level of active c-Src and not with EGF treatment, p190 is considered to be a preferred substrate of c-Src. To determine whether tyrosyl phosphorylation of p190 (by c-Src) could influence EGF-dependent actin remodeling, we used conventional and confocal immunofluorescence microscopy to examine the intracellular distribution of p190, actin, and p120RasGAP in EGF-stimulated or unstimulated 10T1/2 Neo control cells and cells that stably overexpress wild-type (K+) or kinase-defective (K-) c-Src. We found that in all cell lines, EGF induced a rapid and transient condensation of p190 and RasGAP into cytoplasmic, arclike structures. However, in K+ cells the rate of appearance and number of cells exhibiting arcs increased when compared with control cells. Conversely, K- cells exhibited delayed arc formation and a reduction in number of cells forming arcs. EGF-induced actin stress fiber disassembly and reassembly occurred with the same kinetics and frequency as did p190 and RasGAP rearrangements in all three cell lines. These results, together with the documented Rho-GAP activity intrinsic to p190 and the ability of Rho to modulate actin stress fiber formation, suggest that c-Src regulates EGF-dependent actin cytoskeleton reorganization through phosphorylation of p190.
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Rathjen JP, Chang JH, Staskawicz BJ, Michelmore RW. Constitutively active Pto induces a Prf-dependent hypersensitive response in the absence of avrPto. EMBO J 1999; 18:3232-40. [PMID: 10369664 PMCID: PMC1171404 DOI: 10.1093/emboj/18.12.3232] [Citation(s) in RCA: 128] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Resistance in tomato to Pseudomonas syringae pv tomato (avrPto) is conferred by the gene Pto in a gene-for-gene relationship. A hypersensitive disease resistance response (HR) is elicited when Pto and avrPto are expressed experimentally within the same plant cell. The kinase capability of Pto was required for AvrPto-dependent HR induction. Systematic mutagenesis of the activation segment of Pto kinase confirmed the homologous P+1 loop as an AvrPto-binding determinant. Specific amino acid substitutions in this region led to constitutive induction of HR upon expression in the plant cell in the absence of AvrPto. Constitutively active Pto mutants required kinase capability for activity, and were unable to interact with proteins previously shown to bind to wild-type Pto. The constitutive gain-of-function phenotype was dependent on a functional Prf gene, demonstrating activation of the cognate disease resistance pathway and precluding a role for Prf upstream of Pto.
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Spinella MJ, Freemantle SJ, Sekula D, Chang JH, Christie AJ, Dmitrovsky E. Retinoic acid promotes ubiquitination and proteolysis of cyclin D1 during induced tumor cell differentiation. J Biol Chem 1999; 274:22013-8. [PMID: 10419526 DOI: 10.1074/jbc.274.31.22013] [Citation(s) in RCA: 126] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023] Open
Abstract
Mechanisms by which differentiation programs engage the cell cycle are poorly understood. This study demonstrates that retinoids promote ubiquitination and degradation of cyclin D1 during retinoid-induced differentiation of human embryonal carcinoma cells. In response to all-trans-retinoic acid (RA) treatment, the human embryonal carcinoma cell line NT2/D1 exhibits a progressive decline in cyclin D1 expression beginning when the cells are committed to differentiate, but before onset of terminal neuronal differentiation. The decrease in cyclin D1 protein is tightly associated with the accumulation of hypophosphorylated forms of the retinoblastoma protein and G(1) arrest. In contrast, retinoic acid receptor gamma-deficient NT2/D1-R1 cells do not growth-arrest or accumulate in G(1) and have persistent cyclin D1 overexpression despite RA treatment. Notably, stable transfection of retinoic acid receptor gamma restores RA-mediated growth suppression and differentiation to NT2/D1-R1 cells and restores the decline of cyclin D1. The proteasome inhibitor LLnL blocks this RA-mediated decline in cyclin D1. RA treatment markedly accelerates ubiquitination of wild-type cyclin D1, but not a cyclin D1 (T286A) mutant. Transient expression of cyclin D1 (T286A) in NT2/D1 cells blocks RA-mediated transcriptional decline of a differentiation-sensitive reporter plasmid and represses induction of immunophenotypic neuronal markers. Taken together, these findings strongly implicate RA-mediated degradation of cyclin D1 as a means of coupling induced differentiation and cell cycle control of human embryonal carcinoma cells.
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Chang JH, McCluskey PJ, Wakefield D. Toll-like receptors in ocular immunity and the immunopathogenesis of inflammatory eye disease. Br J Ophthalmol 2006; 90:103-8. [PMID: 16361678 PMCID: PMC1856909 DOI: 10.1136/bjo.2005.072686] [Citation(s) in RCA: 124] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Microbial agents have an important role in the pathogenesis of various inflammatory eye diseases, such as uveitis and keratitis. Microbial infections of the eye such as microbial keratitis, ocular onchocerciasis, bacterial endophthalmitis, viral retinitis, and other infectious uveitis are unfortunately common. In addition, microbial agents have been implicated in the pathogenesis of "non-infectious" immune mediated diseases such as HLA-B27 associated acute anterior uveitis. Toll-like receptors (TLR) are a family of pattern recognition receptors that initiates rapid host innate immune response to microbial components known as pathogen associated molecular patterns, which are unique to a given class of microbes, such as lipopolysaccharide of Gram negative bacteria. Recent in vitro and in vivo studies have demonstrated the expression and function of TLRs in the eye, with significant implications for better understanding of ocular immunity and the pathogenesis of inflammatory eye diseases affecting the cornea, uvea, and retina.
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Review |
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Park YW, Han K, Ahn SS, Bae S, Choi YS, Chang JH, Kim SH, Kang SG, Lee SK. Prediction of IDH1-Mutation and 1p/19q-Codeletion Status Using Preoperative MR Imaging Phenotypes in Lower Grade Gliomas. AJNR Am J Neuroradiol 2018; 39:37-42. [PMID: 29122763 DOI: 10.3174/ajnr.a5421] [Citation(s) in RCA: 115] [Impact Index Per Article: 16.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2017] [Accepted: 08/14/2017] [Indexed: 12/27/2022]
Abstract
BACKGROUND AND PURPOSE WHO grade II gliomas are divided into three classes: isocitrate dehydrogenase (IDH)-wildtype, IDH-mutant and no 1p/19q codeletion, and IDH-mutant and 1p/19q-codeleted. Different molecular subtypes have been reported to have prognostic differences and different chemosensitivity. Our aim was to evaluate the predictive value of imaging phenotypes assessed with the Visually AcceSAble Rembrandt Images lexicon for molecular classification of lower grade gliomas. MATERIALS AND METHODS MR imaging scans of 175 patients with lower grade gliomas with known IDH1 mutation and 1p/19q-codeletion status were included (78 grade II and 97 grade III) in the discovery set. MR imaging features were reviewed by using Visually AcceSAble Rembrandt Images (VASARI); their associations with molecular markers were assessed. The predictive power of imaging features for IDH1-wild type tumors was evaluated using the Least Absolute Shrinkage and Selection Operator. We tested the model in a validation set (40 subjects). RESULTS Various imaging features were significantly different according to IDH1 mutation. Nonlobar location, larger proportion of enhancing tumors, multifocal/multicentric distribution, and poor definition of nonenhancing margins were independent predictors of an IDH1 wild type according to the Least Absolute Shrinkage and Selection Operator. The areas under the curve for the prediction model were 0.859 and 0.778 in the discovery and validation sets, respectively. The IDH1-mutant, 1p/19q-codeleted group frequently had mixed/restricted diffusion characteristics and showed more pial invasion compared with the IDH1-mutant, no codeletion group. CONCLUSIONS Preoperative MR imaging phenotypes are different according to the molecular markers of lower grade gliomas, and they may be helpful in predicting the IDH1-mutation status.
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Research Support, Non-U.S. Gov't |
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Chang JH, Chang JW, Choi JY, Park YG, Chung SS. Complications after gamma knife radiosurgery for benign meningiomas. J Neurol Neurosurg Psychiatry 2003; 74:226-30. [PMID: 12531956 PMCID: PMC1738258 DOI: 10.1136/jnnp.74.2.226] [Citation(s) in RCA: 115] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
OBJECTIVES To analyse the results of gamma knife radiosurgery (GKS) for the treatment of intracranial meningiomas and to assess possible factors related to the outcome and complications of such treatment. METHODS The authors retrospectively reviewed the clinical and radiological data of 179 patients (194 lesions) treated with GKS for meningiomas between May 1992 and October 2000. The mean follow up duration was 37.3 months (range 6.4 to 86.3 months). The study determined the correlation between radiosurgical outcome including imaging changes after GKS and multiple factors such as tumour location and size, patient characteristics, venous sinus status, pre-GKS degree of oedema, other treatment modalities, and radiosurgical parameters. RESULTS The radiological control rate was 97.1%. Magnetic resonance imaging (MRI) showed complications after GKS in 35 lesions (25.0%) among the 140 lesions followed up with MRI. Complications were divided into peritumorous imaging changes (33 lesions; 23.6%) and transient cranial nerve dysfunction (two lesions; 1.4%). Radiation induced imaging changes were seen mostly in convexity, parasagittal, and falx meningiomas that were deeply embedded in the cortex. About 60% of these were asymptomatic and the overall rate of symptomatic imaging changes was 9.3%. Neurological deficit related to imaging changes developed in only three patients, and all the symptoms were transient. CONCLUSION GKS for intracranial meningiomas seems to be a safe and effective treatment. However, meningiomas of the convexity, parasagittal region, or falx cerebri have a higher incidence of peritumorous imaging changes after GKS than those of the skull base. Therefore, the use of GKS needs to be considered very cautiously in cerebral hemispheric meningiomas, taking into consideration patient age and general condition, tumour size and location, pattern of cortical embedding, relation between the tumour and venous sinuses, presenting symptoms, and patient preference.
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Chang JH, Jiang Y, Pillarisetty VG. Role of immune cells in pancreatic cancer from bench to clinical application: An updated review. Medicine (Baltimore) 2016; 95:e5541. [PMID: 27930550 PMCID: PMC5266022 DOI: 10.1097/md.0000000000005541] [Citation(s) in RCA: 108] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
BACKGROUND Pancreatic cancer (PC) remains difficult to treat, despite the recent advances in various anticancer therapies. Immuno-inflammatory response is considered to be a major risk factor for the development of PC in addition to a combination of genetic background and environmental factors. Although patients with PC exhibit evidence of systemic immune dysfunction, the PC microenvironment is replete with immune cells. METHODS We searched PubMed for all relevant English language articles published up to March 2016. They included clinical trials, experimental studies, observational studies, and reviews. Trials enrolled at Clinical trial.gov were also searched. RESULTS PC induces an immunosuppressive microenvironment, and intratumoral activation of immunity in PC is attenuated by inhibitory signals that limit immune effector function. Multiple types of immune responses can promote an immunosuppressive microenvironment; key regulators of the host tumor immune response are dendritic cells, natural killer cells, macrophages, myeloid derived suppressor cells, and T cells. The function of these immune cells in PC is also influenced by chemotherapeutic agents and the components in tumor microenvironment such as pancreatic stellate cells. Immunotherapy of PC employs monoclonal antibodies/effector cells generated in vitro or vaccination to stimulate antitumor response. Immune therapy in PC has failed to improve overall survival; however, combination therapies comprising immune checkpoint inhibitors and vaccines have been attempted to increase the response. CONCLUSION A number of studies have begun to elucidate the roles of immune cell subtypes and their capacity to function or dysfunction in the tumor microenvironment of PC. It will not be long before immune therapy for PC becomes a clinical reality.
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Review |
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Hong CY, Kim YK, Chang JH, Kim SH, Choi H, Nam DH, Kim YZ, Kwak JH. Novel fluoroquinolone antibacterial agents containing oxime-substituted (aminomethyl)pyrrolidines: synthesis and antibacterial activity of 7-(4-(aminomethyl)-3-(methoxyimino)pyrrolidin-1-yl)-1-cyclopropyl-6- fluoro-4-oxo-1,4-dihydro[1,8]naphthyridine-3-carboxylic acid (LB20304). J Med Chem 1997; 40:3584-93. [PMID: 9357525 DOI: 10.1021/jm970202e] [Citation(s) in RCA: 102] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
New pyrrolidine derivatives, which bear an alkyloxime substituent in the 4-position and an aminomethyl substituent in the 3-position of the pyrrolidine ring, have been synthesized and coupled with various quinolinecarboxylic acids to produce a series of new fluoroquinolone antibacterials. These fluoroquinolones were found to possess potent antimicrobial activity against both Gram-negative and Gram-positive organisms, including methicillin resistant Staphylococcus aureus (MRSA). Variations at the C-8 position of the quinolone nucleus included fluorine, chlorine, nitrogen, methoxy, and hydrogen atom substitution. The activity imparted to the substituted quinolone nucleus by the C-8 substituent was in the order F (C5-NH2) > F (C5-H) > naphthyridine > Cl = OMe = H against Gram-positive organisms. In the case of Gram-negative strains, activity was in the order F (C5-NH2) > naphthyridine = F (C5-H) > H > Cl > OMe. The advantages provided by the newly introduced oxime group of the quinolones were clearly demonstrated by their comparison to a desoximino compound 30. In addition, the oxime moiety greatly improved the pharmacokinetic parameters of the novel quinolones. Among these compounds, compound 20 (LB20304) showed the best in vivo efficacy and pharmacokinetic profile in animals, as well as good physical properties. The MICs (microgram/mL) of LB20304, compound 30, and ciprofloxacin against several test organisms are as follows: S. aureus 6538p (0.008, 0.031, and 0.13), methicillin resistant S. aureus 241 (4, 16, and 128), Streptococcus epidermidis 887E (0.008, 0.016, and 0.13), methicillin resistant S. epidermidis 178 (4, 32, and 128), Enterococcus faecalis 29212 (0.063, 0.13, and 1), Pseudomonas aeruginosa 1912E (0.25, 0.5, and 0.13), Escherichia coli 3190Y (0.008, 0.016, and 0.008), Enterobacter cloacae P99 (0.008, 0.031, and 0.008), Actinobacter calcoaceticus 15473 (0.063, 0.13, and 0.25). On the basis of these promising results, LB20304 was selected as a candidate for further evaluation.
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Kato T, Kure T, Chang JH, Gabison EE, Itoh T, Itohara S, Azar DT. Diminished corneal angiogenesis in gelatinase A-deficient mice. FEBS Lett 2001; 508:187-90. [PMID: 11718713 DOI: 10.1016/s0014-5793(01)02897-6] [Citation(s) in RCA: 99] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
The goal of the present study was to define the role of gelatinase A in angiogenesis. We performed corneal micropocket assays in gelatinase A-deficient mice and their age-matched wild-type littermates. The corneal neovascular area in gelatinase A-deficient mice (0.15+/-0.14 mm(2)) was significantly less than that of wild-type littermates (0.53+/-0.35 mm(2); P<0.01). Similarly, aortic ring assays showed significant reduction of endothelial outgrowth in gelatinase A-deficient mice (0.26+/-0.14 mm(2)) as compared to wild-type littermates (0.44+/-0.06 mm(2); P<0.05). These results suggest that gelatinase A may play an important role in the regulation of corneal angiogenesis.
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Abstract
PURPOSE This clinical study was undertaken to examine the feasibility of a laparoscopic approach for the treatment of documented malrotation. METHODS From May 1994 through January of 1997, 12 patients, aged 5 days to 4 months, weighing 3 to 7 kg, underwent laparoscopic Ladd's procedure for malrotation. All patients had symptoms of intermittent upper intestinal obstruction, and malrotation was documented by an upper gastrointestinal contrast study. None of the patients had acute volvulus or compromised bowel. The procedure was performed using 3 trocars of 3.5 mm diameter. Ports were placed in the infraumbilical ring, and the right and left mid to lower quadrants. A standard Ladd's procedure with appendectomy was performed in all cases. RESULTS All procedures were completed successfully through the laparoscope. Operative times averaged 58 minutes (35 to 120 minutes). One patient with Pierre-Robin underwent a laparoscopic Nissen fundoplication and gastrostomy tube placement at the same time requiring 120 minutes. Feedings were started on postoperative day (POD) 1 in 10 cases and POD 2 in two cases. Hospital stay ranged from 2 to 4 days (average, 2.2) in the patients with isolated malrotation. The patient with Pierre-Robin had a prolonged hospitalization because of chronic respiratory problems not associated with surgery. There were no complications. All patients had resolution of their symptoms. CONCLUSIONS Laparoscopic Ladd's procedure is a safe and effective technique. It can be performed in neonates in times equivalent to standard open techniques, and it appears to allow for earlier feeds and decreased hospital stays.
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Huang HC, Chang JH, Tung SF, Wu RT, Foegh ML, Chu SH. Immunosuppressive effect of emodin, a free radical generator. Eur J Pharmacol 1992; 211:359-64. [PMID: 1535596 DOI: 10.1016/0014-2999(92)90393-i] [Citation(s) in RCA: 91] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
The possible mechanism of immunosuppressive effect of emodin (1,3,8-trihydroxy-6-methylanthraquinone) was investigated in this study. Human mononuclear cells (10(6) cells/ml) were stimulated with 0.25% phytohemagglutinin for 24, 48 and 72 h, and the proliferative response was determined by the uptake of tritiated thymidine. In the presence of emodin (10(-6) to 3 x 10(-5) M), the proliferative response was reduced in a dose-dependent manner. Emodin (3 x 10(-7) to 3 x 10(-5) M) also dose dependently reduced the proliferative response to mixed lymphocyte reaction. After 72 h exposure to emodin (10 microM), interleukin-1 (IL-1), interleukin-2 (IL-2) production and IL-2 receptor expression were all reduced. The structure-activity relationship of emodin and 10 other anthraquione derivatives indicates that the free hydroxyl group at the beta-position of the anthraquinone nucleus plays an important role in the immunosuppressive effect. The suppressive activity of emodin was significantly inhibited by catalase (a scavenger of hydrogen peroxide), but little affected by superoxide dismutase (a scavenger of superoxide radical) and mannitol (a scavenger of hydroxyl radical). Methylene blue and hemoglobin, guanylate cyclase inhibitors, did not significantly affect the suppressive activity of emodin. Nordihydroguaiaretic acid (a lipoxygenase inhibitor) significantly potentiated the suppressive activity whereas quinacrine (a phospholipase A2 inhibitor) and indomethacin (a cyclooxygenase inhibitor) did not significantly affect it. The results suggest that the immunosuppressive effect of emodin may be partly mediated through hydrogen peroxide generated from semiquinone and regulated by arachidonic acid metabolites or byproducts.
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Bugler B, Bourbon H, Lapeyre B, Wallace MO, Chang JH, Amalric F, Olson MO. RNA binding fragments from nucleolin contain the ribonucleoprotein consensus sequence. J Biol Chem 1987. [DOI: 10.1016/s0021-9258(18)60904-4] [Citation(s) in RCA: 90] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
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Chan-Yeung M, Chang JH, Manfreda J, Ferguson A, Becker A. Changes in peak flow, symptom score, and the use of medications during acute exacerbations of asthma. Am J Respir Crit Care Med 1996; 154:889-93. [PMID: 8887581 DOI: 10.1164/ajrccm.154.4.8887581] [Citation(s) in RCA: 86] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
Changes in symptom score and peak expiratory flow (PEF) and the use of medications during the first acute exacerbation of asthma were studied in 41 patients and matched controls who took part in a panel study. An acute exacerbation was defined as the presence of at least one of the following: any unscheduled physician visit, visit to an emergency room, or hospitalization for treatment of asthma; a decrease in PEF by 30% from the patient's best reading; an increase in asthma symptoms during the day and night for over 48 h and not responding to usual medications; and the commencement or doubling of the dose of oral or inhaled steroids for any of the foregoing reasons. Data from -9 to -7 d before the onset of an acute exacerbation were taken as the baseline data, with which the values of the subsequent 14 d were compared. Significant increases in symptoms occurred before a significant reduction in PEF. None of the patients had a decrease of more than 30% in PEF before the onset of symptoms. Daily variation in PEF was not significantly increased from the baseline. Our results suggest that PEF monitoring is not as sensitive as a symptom diary for revealing acute exacerbations of asthma, and that a 30% decrease in PEF is too stringent a criterion for defining an acute exacerbation.
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van den Brink MR, Kapeller R, Pratt JC, Chang JH, Burakoff SJ. The extracellular signal-regulated kinase pathway is required for activation-induced cell death of T cells. J Biol Chem 1999; 274:11178-85. [PMID: 10196203 DOI: 10.1074/jbc.274.16.11178] [Citation(s) in RCA: 84] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
T cells can undergo activation-induced cell death (AICD) upon stimulation of the T cell receptor-CD3 complex. We found that the extracellular signal-regulated kinase (ERK) pathway is activated during AICD. Transient transfection of a dominant interfering mutant of mitogen-activated/extracellular signal-regulated receptor protein kinase kinase (MEK1) demonstrated that down-regulation of the ERK pathway inhibited FasL expression during AICD, whereas activation of the ERK pathway with a constitutively active MEK1 resulted in increased expression of FasL. We also found that pretreatment with the specific MEK1 inhibitor PD98059 prevented the induction of FasL expression during AICD and inhibited AICD. However, PD98059 had no effect on other apoptotic stimuli. We found only very weak ERK activity during Fas-mediated apoptosis (induced by Fas cross-linking). Furthermore, preincubation with the MEK1 inhibitor did not inhibit Fas-mediated apoptosis. Finally, we also demonstrated that pretreatment with the MEK1 inhibitor could delay and decrease the expression of the orphan nuclear steroid receptor Nur77, which has been shown to be essential for AICD. In conclusion, this study demonstrates that the ERK pathway is required for AICD of T cells and appears to regulate the induction of Nur77 and FasL expression during AICD.
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Kim JS, Chang JH, Chung SI, Yum JS. Molecular cloning and characterization of the Helicobacter pylori fliD gene, an essential factor in flagellar structure and motility. J Bacteriol 1999; 181:6969-76. [PMID: 10559162 PMCID: PMC94171 DOI: 10.1128/jb.181.22.6969-6976.1999] [Citation(s) in RCA: 81] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/1999] [Accepted: 09/07/1999] [Indexed: 11/20/2022] Open
Abstract
Helicobacter pylori colonizes the human stomach and can cause gastroduodenal disease. Flagellar motility is regarded as a major factor in the colonizing ability of H. pylori. The functional roles of flagellar structural proteins other than FlaA, FlaB, and FlgE are not well understood. The fliD operon of H. pylori consists of flaG, fliD, and fliS genes, in the order stated, under the control of a sigma(28)-dependent promoter. In an effort to elucidate the function of the FliD protein, a hook-associated protein 2 homologue, in flagellar morphogenesis and motility, the fliD gene (2,058 bp) was cloned and isogenic mutants were constructed by disruption of the fliD gene with a kanamycin resistance cassette and electroporation-mediated allelic-exchange mutagenesis. In the fliD mutant, morphologically abnormal flagellar appendages in which very little filament elongation was apparent were observed. The fliD mutant strain was completely nonmotile, indicating that these abnormal flagella were functionally defective. Furthermore, the isogenic fliD mutant of H. pylori SS1, a mouse-adapted strain, was not able to colonize the gastric mucosae of host mice. These results suggest that H. pylori FliD is an essential element in the assembly of the functional flagella that are required for colonization of the gastric mucosa.
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research-article |
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Rothenberg SS, Bealer JF, Chang JH. Primary laparoscopic placement of gastrostomy buttons for feeding tubes. A safer and simpler technique. Surg Endosc 1999; 13:995-7. [PMID: 10526034 DOI: 10.1007/s004649901154] [Citation(s) in RCA: 81] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
Abstract
BACKGROUND During a 4-year period, 240 gastrostomy buttons were placed in children, as the initial surgical feeding tube, using laparoscopic techniques. MATERIALS AND METHODS The technique requires the use of a minilaparoscope (1.6-mm) and a single 5-mm trocar placed at the exit site for the gastrostomy button. It can also be performed in addition to a laparoscopic fundoplication using the same trocar sites. The technique requires no special instrumentation or kits. When performed alone, operative times average 15 min. When performed with fundoplication, it adds approximately 5-10 min to the time for the procedure. RESULTS There were no intraoperative complications and five (2.1%) postoperative complications. CONCLUSIONS This technique has proven to be simple and effective. It allows primary placement of a gastrostomy button that is cosmetically and functionally superior to a gastrostomy tube.
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Chang JH, Lee IS, Choi JY, Yoon SK, Kim DG, You YK, Chun HJ, Lee DK, Choi MG, Chung IS. Biliary Stricture after Adult Right-Lobe Living-Donor Liver Transplantation with Duct-to-Duct Anastomosis: Long-Term Outcome and Its Related Factors after Endoscopic Treatment. Gut Liver 2010; 4:226-33. [PMID: 20559526 DOI: 10.5009/gnl.2010.4.2.226] [Citation(s) in RCA: 78] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/04/2009] [Accepted: 03/29/2010] [Indexed: 12/11/2022] Open
Abstract
BACKGROUND/AIMS Biliary stricture is the most common and important complication after right-lobe living-donor liver transplantation (RL-LDLT) with duct-to-duct biliary anastomosis. This study evaluated the efficacy and long-term outcome of endoscopic treatment for biliary stricture after LDLT, with the aim of identifying the factors that influence the outcome. METHODS Three hundred and thirty-nine adults received RL-LDLTs with duct-to-duct biliary anastomosis between January 2000 and May 2008 at Kangnam St. Mary's Hospital. Endoscopic retrograde cholangiography (ERC) was performed in 113 patients who had biliary stricture after LDLT. We evaluated the incidence of post-LDLT biliary stricture and the long-term outcome of endoscopic treatment for biliary stricture. The factors related to the outcome were analyzed. RESULTS Biliary strictures developed in 121 (35.7%) patients, 95 (78.5%) of them within 1 year of surgery. The mean number of ERCs performed per patient was 3.2 (range, 1 to 11). The serum biochemical markers decreased significantly after ERC (p<0.001). Stent insertion or stricture dilatation during ERC was successful in 90 (79.6%) patients. After a median follow-up period of 33 months from the first successful treatment with ERC, 48 (42.5%) patients achieved treatment success and 12 (10.6%) patients remained under treatment. The factors related to the outcome of endoscopic treatment were nonanastomotic stricture and stenosis of the hepatic artery (p=0.016). CONCLUSIONS Endoscopic treatment is efficacious and has an acceptable long-term outcome in the management of biliary strictures related to RL-LDLT with duct-to-duct biliary anastomosis. Nonanastomotic stricture and stenosis of the hepatic artery are correlated with a worse outcome of endoscopic treatment.
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Journal Article |
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Rothenberg SS, Wagner JS, Chang JH, Fan LL. The safety and efficacy of thoracoscopic lung biopsy for diagnosis and treatment in infants and children. J Pediatr Surg 1996; 31:100-3; discussion 103-4. [PMID: 8632258 DOI: 10.1016/s0022-3468(96)90328-0] [Citation(s) in RCA: 75] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
Thoracoscopic techniques were used to perform lung biopsies and limited resections in 36 consecutively treated cases. Biopsies were performed for interstitial lung disease in 27 cases, presumed metastatic lesions in 5, and cavitary lesions in 4. Histological diagnosis was obtained in 35 of the 36 cases, and therapy was directly affected by the results in 30 of 36 cases. There were no postoperative complications, and the average hospital stay for patients admitted the morning of surgery was less than 2 days. Limited thoracoscopic resection provides a safe and effective means for diagnosing and treating parenchymal disease of the lung.
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Chang JH, Lunt DK, Smith SB. Fatty acid composition and fatty acid elongase and stearoyl-CoA desaturase activities in tissues of steers fed high oleate sunflower seed. J Nutr 1992; 122:2074-80. [PMID: 1359038 DOI: 10.1093/jn/122.11.2074] [Citation(s) in RCA: 75] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
The effects of a high oleate sunflower seed diet on tissue composition and on fatty acid elongation and desaturation enzyme activities were investigated. Three Simmental calves were fed a standard corn-based diet (2.6% fat); three others were fed the corn-based diet containing 20% high oleate sunflower seed (10.4% fat). Blood samples and perianal adipose tissue samples were obtained at 7, 90 and 180 d on trial. Samples of liver, longissimus dorsi muscle and intestinal mucosa were obtained at the termination of the experiment (195 d on trial). Plasma oleate was higher (P < 0.05) in the cattle fed the sunflower seed, and oleate, myristate (P < 0.05) and stearate (P < 0.06) were elevated in perianal adipose tissue in response to the greater lipid content of the dietary sunflower seed. Dietary sunflower seed decreased the concentration of stearate (P < 0.05) in liver. The high oleate diet significantly (P < 0.05) increased the activity of stearoyl-CoA desaturase activity in muscle, and numerical increases in desaturase activity were observed in liver, adipose and small intestine samples. Elongase activity was unaffected by diet. Because stearate is the primary fatty acid available for absorption in ruminants, elevated oleate in plasma and depressed stearate in liver of cattle fed sunflower seed may have reflected an adaptive response of stearoyl-CoA desaturase in their tissues.
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Research Support, Non-U.S. Gov't |
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Chang JH, Pratt JC, Sawasdikosol S, Kapeller R, Burakoff SJ. The small GTP-binding protein Rho potentiates AP-1 transcription in T cells. Mol Cell Biol 1998; 18:4986-93. [PMID: 9710582 PMCID: PMC109083 DOI: 10.1128/mcb.18.9.4986] [Citation(s) in RCA: 73] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The Rho family of small GTP-binding proteins is involved in the regulation of cytoskeletal structure, gene transcription, specific cell fate development, and transformation. We demonstrate in this report that overexpression of an activated form of Rho enhances AP-1 activity in Jurkat T cells in the presence of phorbol myristate acetate (PMA), but activated Rho (V14Rho) has little or no effect on NFAT, Oct-1, and NF-kappaB enhancer element activities under similar conditions. Overexpression of a V14Rho construct incapable of membrane localization (CAAX deleted) abolishes PMA-induced AP-1 transcriptional activation. The effect of Rho on AP-1 is independent of the mitogen-activated protein kinase pathway, as a dominant-negative MEK and a MEK inhibitor (PD98059) did not affect Rho-induced AP-1 activity. V14Rho binds strongly to protein kinase Calpha (PKCalpha) in vivo; however, deletion of the CAAX site on V14Rho severely diminished this association. Evidence for a role for PKCalpha as an effector of Rho was obtained by the observation that coexpression of the N-terminal domain of PKCalpha blocked the effects of activated Rho plus PMA on AP-1 transcriptional activity. These data suggest that Rho potentiates AP-1 transcription during T-cell activation.
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Chung SS, Chang JH, Choi JY, Chang JW, Park YG. Microvascular decompression for hemifacial spasm: a long-term follow-up of 1,169 consecutive cases. Stereotact Funct Neurosurg 2002; 77:190-3. [PMID: 12428639 DOI: 10.1159/000064620] [Citation(s) in RCA: 68] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
We analyzed the records of 1,169 patients with hemifacial spasm (HFS) who underwent microvascular decompression (MVD) and were followed up for more than 6 months from January 1987. The mean follow-up duration was 23.8 months (6-145 months). Excellent surgical outcome was obtained in 90.5% and good in 4.5%, giving an overall success rate of 95.0%. There was statistically significant relationship between vertebral artery (VA) shift and side of symptom. Permanent facial weakness and hearing impairment were 1.4% and 2.3%, respectively. There were no anatomical differences at the root entry zone (REZ) and significant differences of surgical outcome in young HFS (34 patients). Factors such as type of offender, severity of compression on the facial nerve root, and the degree of decompression of the REZ on postoperative MRI did not correlate with surgical outcome.
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Comparative Study |
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68 |