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Hong TH, Hwang S, Choi YL, Lee G, Park S, Ahn MJ, Lee Y, Jeon YJ, Lee J, Shin S, Park SY, Cho JH, Choi YS, Kim J, Shim YM, Cho J, Kim HK. Different prognostic role of EGFR mutation according to the IASLC histological grade in patients with resected early-stage lung adenocarcinoma. Histopathology 2023. [PMID: 36849852 DOI: 10.1111/his.14894] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2022] [Revised: 02/02/2023] [Accepted: 02/21/2023] [Indexed: 03/01/2023]
Abstract
AIMS The prognostic role of EGFR mutations remains controversial. We aimed to evaluate the prognostic role of EGFR mutation in consideration of the IASLC histological grade in patients with resected early-stage lung adenocarcinoma. METHODS AND RESULTS A total of 3297 patients with stages I-IIA resected lung adenocarcinoma who had had EGFR mutation tests between January 2014 and December 2019 at the Samsung Medical Center, Seoul, Korea were included. Recurrence-free survival (RFS) was compared by EGFR mutation status (EGFR-M+ versus EGFR-WT) and IASLC histological grade (G1, G2 and G3). Cox proportional hazards models were used to estimate the adjusted HRs (aHRs) and 95% confidence intervals (CIs). RESULTS Compared to the EGFR-WT group, the EGFR-M+ group had a significantly lower proportion of G3 tumour (16 versus 33%, P < 0.001). During a median follow-up of 41.4 months, 376 patients experienced recurrence. After adjusting for histological grade, the aHR for recurrence comparing the EGFR-M+ to the EGFR-WT was 1.30 (95% CI = 1.04-1.62, P = 0.022). The EGFR-M+ group had a significantly lower 5-year RFS than the EGFR-WT group among G3 patients (58.4 versus 71.5%, P < 0.001), but not among G1 and G2 patients. CONCLUSIONS EGFR mutation status was associated with a risk of recurrence after consideration of the IASLC histological grading, especially in G3 tumours. The results of this study would be useful for developing a new staging system and identifying a subset of patients who may benefit from adjuvant targeted therapy.
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Affiliation(s)
- Tae H Hong
- Department of Thoracic and Cardiovascular Surgery, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.,Department of Digital Health, SAIHST, Sungkyunkwan University, Seoul, Korea
| | - Soohyun Hwang
- Department of Pathology and Translational Genomics, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea
| | - Yoon-La Choi
- Department of Pathology and Translational Genomics, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea
| | - Genehee Lee
- Samsung Medical Center, Patient-Centered Outcomes Research Institute, Seoul, Korea.,Department of Clinical Research Design and Evaluation, SAIHST, Sungkyunkwan University, Seoul, Korea
| | - Sehhoon Park
- Division of Hematology-Oncology, Department of Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea
| | - Myung-Ju Ahn
- Division of Hematology-Oncology, Department of Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea
| | - Yoonseo Lee
- Department of Thoracic and Cardiovascular Surgery, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea
| | - Yeong J Jeon
- Department of Thoracic and Cardiovascular Surgery, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea
| | - Junghee Lee
- Department of Thoracic and Cardiovascular Surgery, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea
| | - Sumin Shin
- Department of Thoracic and Cardiovascular Surgery, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.,Department of Thoracic and Cardiovascular Surgery, School of Medicine, Ewha Womans University, Mok-Dong Hospital, Seoul, Korea
| | - Seong Y Park
- Department of Thoracic and Cardiovascular Surgery, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea
| | - Jong H Cho
- Department of Thoracic and Cardiovascular Surgery, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea
| | - Yong S Choi
- Department of Thoracic and Cardiovascular Surgery, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea
| | - Jhingook Kim
- Department of Thoracic and Cardiovascular Surgery, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea
| | - Young M Shim
- Department of Thoracic and Cardiovascular Surgery, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.,Samsung Medical Center, Patient-Centered Outcomes Research Institute, Seoul, Korea
| | - Juhee Cho
- Samsung Medical Center, Patient-Centered Outcomes Research Institute, Seoul, Korea.,Department of Clinical Research Design and Evaluation, SAIHST, Sungkyunkwan University, Seoul, Korea.,Center for Clinical Epidemiology, Samsung Medical Center, Future Medicine Institute, Seoul, Korea
| | - Hong K Kim
- Department of Thoracic and Cardiovascular Surgery, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.,Samsung Medical Center, Patient-Centered Outcomes Research Institute, Seoul, Korea.,Department of Clinical Research Design and Evaluation, SAIHST, Sungkyunkwan University, Seoul, Korea
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2
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Kim EY, Hong TH. Changes in natural killer cell activity after surgery and predictors of its recovery-failure. J Surg Oncol 2021; 124:1561-1568. [PMID: 34351633 DOI: 10.1002/jso.26636] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2021] [Revised: 07/06/2021] [Accepted: 07/25/2021] [Indexed: 12/20/2022]
Abstract
BACKGROUND AND OBJECTIVES We evaluated the changes in natural killer cell activity (NKA) during the entire treatment period of patients with resectable biliopancreatic cancers and investigated the predictors of the failure of recovery of NKA after surgery. METHODS A total of 202 patients who underwent curative resection for biliopancreatic cancer were enrolled in the study. NKA levels were measured six times during the treatment period. We investigated whether there was any difference in postoperative NKA recovery according to the period-by-time NKA value. RESULTS NKA decreased after surgery (mean, 40 pg/ml) compared to the NKA value at admission (200.2 pg/ml), then began to increase from 3 weeks after surgery (139.7 pg/ml) and rose to normal NKA levels at 5 weeks (217.1 pg/ml). The pattern of NKA changes was distinct according to the NKA values at admission. In multivariate analysis, NKA values of less than 250 pg/ml at admission (odds ratio = 5.898, p = 0.044) were a predictor of NKA recovery failure 5 weeks after surgery. CONCLUSIONS NKA rapidly decreased after curative surgery for biliopancreatic cancer and recovered to normal levels about 5 weeks later. Clinicians should be aware and cautious that patients with low NKA at admission may fail to recover NKA postoperatively.
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Affiliation(s)
- Eun Y Kim
- Division of Trauma and Surgical Critical Care, Department of Surgery, Seoul St. Mary's Hospital, College of Medicine, The Catholic University of Korea, Seoul, Republic of Korea
| | - Tae H Hong
- Division of Hepato-biliary and Pancreas Surgery, Department of Surgery, Seoul St. Mary's Hospital, College of Medicine, The Catholic University of Korea, Seoul, Republic of Korea
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Hong TH, Lee JH, Seo CH, Kim KH, Kim HY. Vibration reduction during milling of highly flexible workpieces using active workpiece holder system. Rev Sci Instrum 2021; 92:045105. [PMID: 34243429 DOI: 10.1063/5.0046394] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/03/2021] [Accepted: 03/16/2021] [Indexed: 06/13/2023]
Abstract
The milling of highly flexible workpieces, such as thin-walled structures used in turbine blades, aerospace equipment, and jet engine compressors, requires vibration compensation to improve the quality of the workpiece surface. Vibration can be reduced by selecting appropriate cutting parameters. However, this approach reduces system productivity. This paper presents an active workpiece holder that controls the vibration of general computer numerical control machine tools. The proposed holder, which comprises a flexible guide mechanism, driver, and sensor, measures vibration and actively controls it using piezoactuators. A high-rigidity flexure mechanism was designed for the holder, and finite element method simulation and modal analysis were performed. Finally, the proposed system was fabricated, and experimental verification indicated that the system reduced vibration. The surface quality obtained using the controlled system was ∼50% better than that obtained using the uncontrolled system.
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Affiliation(s)
- T H Hong
- Manufacturing System R&D Group, Korea Institute of Industrial Technology, Cheonan-si 31056, South Korea
| | - J H Lee
- Manufacturing System R&D Group, Korea Institute of Industrial Technology, Cheonan-si 31056, South Korea
| | - C H Seo
- Mechanical Engineering, Ajou University, 206, Worldcup-ro Yeongtong-gu, Suwon, Gyeonggi-do 16499, South Korea
| | - K H Kim
- Mechatronics Engineering, Korea Polytechnic University, Siheung-si 15073, South Korea
| | - H Y Kim
- Manufacturing System R&D Group, Korea Institute of Industrial Technology, Cheonan-si 31056, South Korea
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4
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Kim EY, Hong TH. Changes in total lymphocyte count and neutrophil‐to‐lymphocyte ratio after curative pancreatectomy in patients with pancreas adenocarcinoma and their prognostic role. J Surg Oncol 2019; 120:1102-1111. [DOI: 10.1002/jso.25725] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2019] [Accepted: 09/27/2019] [Indexed: 12/18/2022]
Affiliation(s)
- Eun Y. Kim
- Division of Trauma and Surgical Critical Care, Department of Surgery, Seoul St. Mary's Hospital, College of MedicineThe Catholic University of Korea Seoul Republic of Korea
| | - Tae H. Hong
- Division of Hepato‐biliary and Pancreas Surgery, Department of Surgery, Seoul St. Mary's Hospital, College of MedicineThe Catholic University of Korea Seoul Republic of Korea
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Na GH, Kim EY, Hong TH, You YK, Kim DG. Effects of loco regional treatments before living donor liver transplantation on overall survival and recurrence-free survival in South Korean patients with hepatocellular carcinoma. HPB (Oxford) 2016; 18:98-106. [PMID: 26776857 PMCID: PMC4750233 DOI: 10.1016/j.hpb.2015.08.008] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/30/2015] [Revised: 06/18/2015] [Accepted: 08/09/2015] [Indexed: 02/08/2023]
Abstract
BACKGROUND We evaluated the effects of pre-transplant locoregional treatment on survival in living donor liver transplantation (LDLT), and the most accurate method for predicting survival after LDLT in patients who received pre-transplant locoregional treatment. METHODS From December 2003 to December 2012, 234 patients underwent LDLT for hepatocellular carcinoma (HCC) at our transplant center. We retrospectively reviewed 86 patients newly diagnosed with HCC and who received pre-transplant locoregional treatments at our hospital. RESULTS Of the 33 patients with HCC initially beyond the Milan criteria, 12 experienced successful down-staging after locoregional treatments, and the 5-year recurrence-free survival was 81.8%, which was comparable to those in patients with HCC initially within the Milan criteria. A bad responder according to the modified Response Evaluation Criteria in Solid Tumors (mRECIST) [HR, 4.874 (1.059-22.442), p = 0.042], and increased AFP levels [HR 4.002 (1.540-10.397), p = 0.004] during pre-transplant locoregional treatments were independent risk factors for HCC recurrence after LDLT in multivariate analysis. CONCLUSIONS Liver transplantation may be considered after successful down-staging in patients with HCC initially beyond the Milan criteria. The mRECIST and serum AFP level changes are better selection criteria for LDLT in patients who have received locoregional treatments.
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Affiliation(s)
| | | | | | | | - Dong G. Kim
- Correspondence Dong G. Kim, Department of Surgery, Seoul St. Mary's Hospital, College of Medicine, The Catholic University of Korea, 505 Banpo-dong, Seocho-gu, Seoul 137-701, South Korea. Tel: +82 2 2258 6096. Fax: +82 2 595 2822.
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Choi HJ, You YK, Na GH, Hong TH, Shetty GS, Kim DG. Single-port laparoscopy-assisted donor right hepatectomy in living donor liver transplantation: sensible approach or unnecessary hindrance? Transplant Proc 2012; 44:347-52. [PMID: 22410013 DOI: 10.1016/j.transproceed.2012.01.018] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
BACKGROUND Single-port laparoscopic (SPL) surgery has rapidly gained attention worldwide. Since May 2008, we have propagated the use of SPL surgery, mainly for cholecystectomy and appendectomy. Recently, we have used this modality of minimally invasive surgery for various liver surgeries. We hereby discuss our outcomes of SPL-assisted donor right hepatectomies. METHODS The preoperative workup is the same as for a standard donor hepatectomy. We retrospectively reviewed the data of 150 patients who underwent donor right hepatectomy from October 2008 to May 2011. We divided them into 3 groups depending on the type of surgical procedure. RESULTS Among 150 patients, 20 underwent laparoscopy-assisted donor right hepatectomy (LADRH); 40 underwent single-port laparoscopy-assisted donor right hepatectomy (SPLADRH); and 90 underwent open donor right hepatectomy (ODRH). The donor demographics were comparable among the groups. Postoperative complication and reoperation rates revealed no significant differences. The SPLADRH group showed the lowest level of postoperative pain, thereby leading to a better quality of life postoperatively. CONCLUSIONS SPLADRH seems to be a simple, feasible approach.
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Affiliation(s)
- H J Choi
- Department of Surgery, Division of Hepatobiliary-Pancreas Surgery, Seoul St. Mary's Hospital, The Catholic University of Korea, Seoul, Korea
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Abstract
Female urinary retention is extremely rare. Two cases of female urethral carcinoma that presented as urinary retention are reviewed and discussed.
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Affiliation(s)
- K C Kobashi
- Virginia Mason Medical Center, Seattle, Washington 98101, USA
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Hong JC, Hong TH, Chang JG, Chang TH. Production and characterization of monoclonal antibodies against alpha and beta spectrin subunits. J Formos Med Assoc 1993; 92:61-7. [PMID: 8099829] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
Twenty monoclonal antibodies against human erythrocyte spectrin were generated using purified native spectrin as the immunogen. Thirteen out of 20 monoclonal antibodies reacted to the alpha subunit, and the remaining seven monoclonal antibodies reacted to the beta subunit in Western blot analysis. One anti-beta subunit and two anti-alpha subunit monoclonal antibodies cross-reacted with the cell lysate of the non-erythroid T. lymphoma, J. Jhan, cell line. Identification of 20 monoclonal antibodies to the respective tryptic domains was also achieved. The specificity of these antibodies to respective tryptic domains of spectrin confirms the alignments and uniqueness of each of the previously identified five domains in the alpha subunit and four domains in the beta subunit, and establishes the identity of proteolytic daughter peptide fragments.
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Affiliation(s)
- J C Hong
- Cell Biology and Immunology Division, Development Center for Biotechnology, Taipei, Taiwan, R.O.C
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Hong TH, Hsiao SC, Sheu WJ, Chang TH. Characterization and nucleotide sequences of the variable regions of a monoclonal antibody against alpha-fetoprotein. Hybridoma (Larchmt) 1992; 11:339-50. [PMID: 1379974 DOI: 10.1089/hyb.1992.11.339] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
alpha-Fetoprotein (AFP) is a well-known tumor marker of hepatocellular carcinoma (HCC). Monoclonal antibodies against AFP possessing specific binding ability to HCC are potential candidates for immunoscintigraphy and immunotherapy. A new monoclonal antibody against AFP (0325-6-9) was isolated. Its specificity and targeting tumor ability were characterized by enzyme-linked immunosorbent assay (ELISA), cell immunostain and complement killing. These results suggest that 0325-6-9 is specific to hepatoma cells. The nucleotide sequences of variable regions of 0325-6-9 were determined by M13 dideoxynucleotide sequencing method. With the information of nucleotide sequence, this antibody then could be modified by recombinant technology for its usage in in vivo diagnosis and immunotherapy.
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Affiliation(s)
- T H Hong
- Cell Biology and Immunology Division, Development Center for Biotechnology, Taipei, Taiwan, R.O.C
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Hsu CH, Hong TH, Yin KW, Tang TK, Wang SC, Chen ST, Lee LS, Chang TH. Purification of radioiodinated human insulin by high performance liquid chromatography for a sensitive radioimmunoassay. J Formos Med Assoc 1992; 91:9-14. [PMID: 1352342] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/25/2023] Open
Abstract
The optimal sensitivity of a radioimmunoassay depends on the purity of the radiolabeled antigen. The conventional purification methods are not complete and are time consuming. The combination of a Sep-pak C18 cartridge and high performance liquid chromatography (HPLC) for the purification of 125I-labeled insulin in our study revealed that the Sep-pak cartridge can serve as the preliminary step to remove unreacted radioactive iodide, the reactants, and labeled but presumably damaged materials unadsorbed to the cartridge. The fractions eluted from the Sep-pak containing high radioactivity and high immunoreactivity to the antibody were chosen for further purification by HPLC to eliminate undesirable radiolabeled substances with a lesser immunoreactivity. The purified radiolabeled insulin was used to develop a sensitive radioimmunoassay with detecting limits of 0.03 microU/mL per tube.
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Affiliation(s)
- C H Hsu
- Department of Clinical Pathology, Taipei Municipal Jen-Ai Hospital, Taiwan R.O.C
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Hsu CH, Yin KW, Hong TH, Tang TK, Lee LS, Chang TH, Liu JD, Chen PH. Preparation of radioiodinated secretin for radioimmunoassay. Ann Nucl Med 1991; 5:83-7. [PMID: 1764343 DOI: 10.1007/bf03164619] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Radioiodination of synthetic human secretin on its N-terminal histidyl residue was not difficult when a greater amount of Chloramine T and a longer reaction time were employed to achieve better incorporation of 125I. The radioiodinated tracer for an optimal radioimmunoassay required purification. The combination of Sep-pak C18 Cartridge and high performance liquid chromatography for the purification of 125I-secretin in our study revealed that the Sep-pak cartridge was a preliminary step in removing unlabeled radioactive iodide, the reactant, and labeled materials unadsorbed to the cartridge. The eluate eluted from the Sep-pak containing high radioactivity and high immunoreactivity to the antibody were selected for further purification by HPLC which eliminated undesirable radiolabeled substances with lower immunoreactivity. The purified radiolabeled secretin was used in developing a sensitive radioimmunoassay.
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Affiliation(s)
- C H Hsu
- Department of Clinical Pathology, Taipei Municipal Jen-Ai Hospital, Taiwan, R.O.C
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Abstract
Two novel immunization methods (intrasplenic and intra-inguinal lymph node) have been developed for the production of polyclonal and monoclonal antibodies in mice. Freund's complete adjuvant and antigen were mixed in the ratio of 1:2 (v/v). Various concentrations of human serum albumin (HSA) were used as antigen. No primary immune response was induced with 0.1 microgram of HSA in either of the methods studied. Intrasplenic immunization resulted in the strongest primary immune responses using all other doses of HSA. The primary immune response induced by intrasplenic immunization with 0.5 microgram of HSA was higher than any response induced by subcutaneous immunization with various doses of HSA. Inguinal lymph node immunization was less effective than intrasplenic immunization but better than subcutaneous immunization with 1-50 micrograms of HSA. Comparisons were also made of the efficacy of different adjuvants when inducing primary immune responses with 1 microgram of HSA. Freund's complete adjuvant resulted in a much stronger response than Freund's incomplete adjuvant and alum. Both intrasplenic and inguinal lymph node immunization using 1-5 micrograms of HSA were able to induce strong primary immune responses. Secondary immunization with either method or intravenous injection 3 days before fusion resulted in a higher frequency of specific monoclonal antibodies.
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Affiliation(s)
- T H Hong
- Cell Biology and Immunology Division, Development Center for Biotechnology, Taipei, Taiwan
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Oppermann T, Hong TH, Surzycki SJ. Chloroplast and nuclear genomes of Chlamydomonas reinhardtii share homology with Escherichia coli genes for DNA replication, repair and transcription. Curr Genet 1989; 15:39-46. [PMID: 2663186 DOI: 10.1007/bf00445750] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Most of the cpDNA genes studied to date are genes encoding elements of the photosynthetic apparatus and translational machinery. Much less is known about genes encoding the polypeptides involved in transcription, cpDNA replication, recombination and repair. The similarities between bacterial and some cpDNA genes were exploited to identify some of these chloroplast genes using bacterial probes. Probes derived from the Escherichia coli genes dnaA, recA, uvrC, transcriptional factor rho, and rpoC were used to search for homologous DNA sequences in chloroplast and nuclear genomes of Chlamydomonas reinhardtii. Regions homologous to all of these genes were located on the cpDNA physical map by probing restriction fragments of cpDNA with plasmid fragments containing these genes. Probing nuclear DNA with bacterial gene probes revealed DNA fragments homologous to dnaA and rpoC genes.
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Affiliation(s)
- T Oppermann
- Department of Biology, Indiana University, Bloomington 47405
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Abstract
We examined the mitochondrial transcription and translation products of somatic cell hybrids constructed by the fusion of Chinese hamster and mouse cells. The hybrid cell lines OAC-k, OAC-l, and OAC-m contain approximately equal amounts of hamster and mouse mitochondrial DNA and produced mitochondrial rRNA from both parental species in the same ratio. Cell lines OAC-k, OAC-l, and OAC-m also produced poly(A)+ mouse mitochondrial RNA transcripts comparable in complexity and quantity to poly(A)+ RNA from the mouse parent. However, the overall level of poly(A)+ hamster mitochondrial RNA from these hybrids was significantly reduced compared with that from the hamster parent. The hybrid cells also lacked several poly(A)+ RNA species found in the hamster parent, but contained additional minor transcripts. The mitochondrially coded proteins of the OAC-k, OAC-l, and OAC-m cells were predominantly encoded by the mouse mitochondrial DNA.
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Abstract
This correspondence describes a method of building and maintaining a spatial respresentation for the workspace of a robot, using a sensor that moves about in the world. From the known camera position at which an image is obtained, and two-dimensional silhouettes of the image, a series of cones is projected to describe the possible positions of the objects in the space. When an object is seen from several viewpoints, the intersections of the cones constrain the position and size of the object. After several views have been processed, the representation of the object begins to resemble its true shape. At all times, the spatial representation contains the best guess at the true situation in the world with uncertainties in position and shape explicitly represented. An octree is used as the data structure for the representation. It not only provides a relatively compact representation, but also allows fast access to information and enables large parts of the workspace to be ignored. The purpose of constructing this representation is not so much to recognize objects as to describe the volumes in the workspace that are occupied and those that are empty. This enables trajectory planning to be carried out, and also provides a means of spatially indexing objects without needing to represent the objects at an extremely fine resolution. The spatial representation is one part of a more complex representation of the workspace used by the sensory system of a robot manipulator in understanding its environment.
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Affiliation(s)
- T H Hong
- Robot Systems Division, National Bureau of Standards, Gaithersburg, MD 20899
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Abstract
This correspondence describes a method of extracting compact regions from images using three multiresolution (``pyramid'') representations of image features. The method makes use of a gray-level pyramid in which linking of similar nodes at successive levels smooths the image into uniform regions; an edge pyramid in which linking of similarly oriented edge elements serves to delineate the boundaries of the detected regions; and a ``surroundedness'' pyramid in which pixels surrounded by edges are detected.
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Affiliation(s)
- T H Hong
- Center for Automation Research, University of Maryland, College Park, MD 20742; National Bureau of Standards, Washington, DC 20234
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Abstract
This correspondence describes a method of image segmentation based on a ``pyramid'' of reduced-resolution versions of the image. It defines link strengths between pixels at adjacent levels of the pyramid, based on proximity and similarity, and iteratively recomputes the pixel values and adjusts the link strengths. After a few iterations, the strengths stabilize, and the links that remain strong define subtrees of the pyramid; the leaves of each tree are the pixels belonging to a compact (piece of a) homogeneous region in the image.
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Affiliation(s)
- T H Hong
- Center for Automation Research, University of Maryland, College Park, MD 20742; National Bureau of Standards, Washington, DC 20234
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Chooi WY, Macklin MD, Leiby KR, Hong TH, Scofield SR, Sabatini LM, Burns DK. Purification of Drosophila acidic ribosomal proteins. Eur J Biochem 1982; 127:199-205. [PMID: 6814910 DOI: 10.1111/j.1432-1033.1982.tb06856.x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
The relatively acidic proteins (group A80) of Drosophila melanogaster ribosomes were separated by ion-exchange chromatography. Fractions containing one or more acidic proteins were combined into thirteen pools. The criterion for the combination was the migration pattern in one-dimensional polyacrylamide gels containing sodium dodecyl sulphate. Five proteins (7/8, S25/S27, S14, L1/L2 and L5/L6) required no further purification. The others were further purified as follows: proteins S7, and S9 by preparative gel electrophoresis: and protein 13 (to newly identified protein) by adsorption with conconavalin-A--agarose. Four proteins had no detectable contamination, and in each of the others the impurities were no greater than 3%. The amount of purified protein recovered from a starting amount of 2.63 g total 80-S ribosomal protein and a starting amount of 105 mg group A80 varied from 0.4 mg to 8.8 mg. The molecular weight of the proteins was estimated by polyacrylamide gel electrophoresis in sodium dodecyl sulphate. The amino acid composition of the individual purified proteins was determined. Several phosphorylated proteins were identified. Proteins 13b and 13c are phosphorylated derivatives of 13a; 7b/8b and 7c/8c are phosphorylated derivatives of 7a and/or 8a. Proteins 7/8 and 13 are distinct proteins but are very similar in amino acid composition.
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Abstract
A simple class of piecewise constant approximations to an image is constructed as follows: start with the entire image, subdivide it into quadrants if its gray level standard deviation is high, and repeat the process for each quadrant. This yields a decomposition of the image into blocks, each having low standard deviation, so that each of them can be approximated by a constant value, namely, its mean. The histogram of this approximated image tends to have sharper peaks than that of the original image since the block averaging reduces the variability of the gray levels within homogeneous regions. A possible way of further improving the histogram is based on the fact that small blocks tend to occur near region borders; thus, suppressing these blocks should tend to deepen the valleys on the histogram, making threshold selection (to separate regions of different types) easier. Conversely, the histogram of the small blocks only represents a population of pixels near region borders, and if there are only two types of regions (e.g., objects and background), the mean of this histogram should be a useful threshold for separating them; but in practice, this method is not very reliable since background fluctuations also give rise to border pixels.
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Affiliation(s)
- A Y Wu
- Computer Vision Laboratory, Computer Science Center, University of Maryland, College Park, MD 20742
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