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Soe MT, Shibata Y, Win Htun M, Abe K, Soe K, Win Than N, Lwin T, Phone Kyaw M, Koji T. Immunohistochemical Mapping of Bcl9 Using Two Antibodies that Recognize Different Epitopes Is Useful to Characterize Juvenile Development of Hepatocellular Carcinoma in Myanmar. Acta Histochem Cytochem 2019; 52:9-17. [PMID: 30923411 PMCID: PMC6434316 DOI: 10.1267/ahc.18045] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2018] [Accepted: 12/13/2018] [Indexed: 01/10/2023] Open
Abstract
B-cell lymphoma 9 (Bcl9) is the core component of Wnt/β-catenin signaling and overexpressed in nuclei of various tumors, including hepatocellular carcinoma (HCC). However, the extent of Bcl9 expression relative to HCC differentiation stage and its functional aspects are poorly understood. In this study, we examined the expression pattern of Bcl9 immunohistochemically, using two anti-Bcl9 antibodies; one was a conventional polyclonal-antibody (anti-Bcl9ABC) against amino acid no.800-900 of human-Bcl9, while the other (anti-Bcl9BIO) was against amino acid no.50-200, covering Pygopus-binding sites of Bcl9. Immunohistochemistry using anti-Bcl9BIO demonstrated distinctive staining in the cytoplasm, while the anti-Bcl9ABC signal was detected in both cytoplasm and nuclei of HCC cells, reflecting different states of Bcl9 function because Pygopus-binding to Bcl9 is essential to exert its function together with β-catenin in nucleus. Quantitative analysis revealed a significantly higher immunohistochemical-score by anti-Bcl9BIO in normal liver comparing various differentiation grades of HCC (P < 0.004), whereas no significant difference was noted with anti-Bcl9ABC. Interestingly, immunohistochemical-score of anti-Bcl9BIO in patients aged < 40 years was significantly lower than that of ≥ 40 years group (P < 0.01). The results indicated that anti-Bcl9BIO detected cytoplasmic Bcl9, which does not bind to Pygopus suggesting it could be a useful indicator for development of HCC in young Myanmar patients.
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Affiliation(s)
- Myat Thu Soe
- Department of Histology and Cell Biology, Nagasaki University Graduate School of Biomedical Sciences
| | - Yasuaki Shibata
- Department of Histology and Cell Biology, Nagasaki University Graduate School of Biomedical Sciences
| | - Myo Win Htun
- Department of Histology and Cell Biology, Nagasaki University Graduate School of Biomedical Sciences
| | - Kuniko Abe
- Department of Pathology, Japanese Red Cross Nagasaki Atomic Bomb Hospital
| | | | - Nay Win Than
- Department of Hepatobiliary and Pancreatic Surgery, Yangon Specialty Hospital
| | - Thann Lwin
- Department of Hepatobiliary and Pancreatic Surgery, Yangon Specialty Hospital
| | | | - Takehiko Koji
- Department of Histology and Cell Biology, Nagasaki University Graduate School of Biomedical Sciences
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Thu A, Win H, Nyunt MT, Lwin T. Knowledge, attitudes and practice concerning tuberculosis in a growing industrialised area in Myanmar. Int J Tuberc Lung Dis 2012; 16:330-5. [PMID: 22640446 DOI: 10.5588/ijtld.10.0754] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
SETTING Factories in industrial zones in Yangon, Myanmar, one of the 22 high tuberculosis (TB) burden countries. OBJECTIVES To assess workers' knowledge about TB, their health-seeking behaviour, acceptability of TB screening and predictors for approval of the dismissal of TB patients. DESIGN In a cross-sectional survey, structured interviews with 349 factory workers were followed by 27 in-depth interviews and two focus group discussions with employers. RESULTS Among 349 workers, 95% perceived TB as being curable, 50% correctly reported air as the main mode of transmission and 68% were aware of free treatment. Although 88% perceived screening before employment as necessary, only 14% underwent screening; 96% were willing to undergo contact screening for TB, but only 55% could afford it; 33% agreed with the dismissal of workers with TB, which was associated with lower education, shorter time in employment, not having a history of TB contact and unwillingness to work with an index TB case due to fear and lack of knowledge. CONCLUSION More effective communication strategies towards factory workers are needed to increase workers' knowledge about transmission and reduce stigma. Employers should be sensitised to protect employees with TB and invest in preventive activities.
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Affiliation(s)
- A Thu
- Clinical Research Division, Department of Medical Research, Lower Myanmar, Yangon, Myanmar
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Lwin T, Hazlehurst LA, Li Z, Dessureault S, Sotomayor E, Moscinski LC, Dalton WS, Tao J. Bone marrow stromal cells prevent apoptosis of lymphoma cells by upregulation of anti-apoptotic proteins associated with activation of NF-kappaB (RelB/p52) in non-Hodgkin's lymphoma cells. Leukemia 2007; 21:1521-31. [PMID: 17476277 DOI: 10.1038/sj.leu.2404723] [Citation(s) in RCA: 70] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Stromal cells are an essential component of the bone marrow microenvironment that regulate or supports tumor survival. In this study we therefore studied the role of stromal cells in lymphoma cell survival. We demonstrated that adhesion of the B-cell lymphoma cell lines SUDH-4 and 10 to bone marrow stroma inhibited mitoxantrone-induced apoptosis. This adhesion-dependent inhibition of mitoxantrone-induced apoptosis correlated with decreased activation of caspases-8 and 9, and cleavage of caspase 3 and PARP. Electrophoretic mobility shift assays (EMSA) analysis demonstrated significantly increased NF-kappaB binding activity in lymphoma cells adhered to stroma cells compared to lymphoma cells in suspension. This DNA binding activity could be attributed to cell adhesion-mediated proteolysis of the NF-kappaB precursor, p100 (NF-kappaB2). This resulted in the generation of active p52, which translocated to the nucleus in complex with p65 and RelB. Coculture with stromal cells also induced expression of the NF-kappaB-regulated anti-apoptotic molecules, XIAP, cIAP(1) and cIAP(2). Inhibition of NF-kappaB significantly suppressed HS-5-induced protection against apoptosis in lymphoma cell lines as well as in primary lymphoma cells. Thus, bone marrow stroma protects B-cell lymphoma cells against apoptosis, at least in part through activation of NF-kappaB dependent mechanism involving up-regulation of NF-kappaB regulated antiapoptotic proteins. Consequently, this study suggests a new approach to decrease the resistance of lymphoma to chemotherapy.
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Affiliation(s)
- T Lwin
- Department of Interdisciplinary Oncology and Experimental Therapeutics Program, H. Lee Moffitt Cancer Center and Research Institute at the University of South Florida, Tampa, FL 33613, USA
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Ti T, Lwin T, Mar TT, Maung W, Noe P, Htun A, Kluge HH, Wright A, Aziz MA, Paramasivan CN. National anti-tuberculosis drug resistance survey, 2002, in Myanmar. Int J Tuberc Lung Dis 2006; 10:1111-6. [PMID: 17044203] [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: 05/12/2023] Open
Abstract
SETTING Thirty townships of Myanmar. OBJECTIVES To determine the proportions of drug-resistant tuberculosis (TB) in new and previously treated pulmonary tuberculosis (PTB) cases in Myanmar. DESIGN A cross-sectional study. Drug susceptibility was tested by the proportion method at the National Tuberculosis Reference Laboratory, Yangon. RESULTS Of 874 TB patients included from 30 sites, 849 isolates obtained from individual patients (733 from new cases and 116 from previously treated cases) were tested for susceptibility to four primary anti-tuberculosis drugs. Of 733 isolates tested from new TB patients, 10% were resistant to any one of the anti-tuberculosis drugs, 6.5% to isoniazid (INH), 4.6% to rifampicin (RMP) and 4.0% were multidrug-resistant (MDR). Of the 116 previously treated patients, 30.2% were resistant to any one of the drugs, 26.7% to INH, 15.5% to RMP and 15.5% were MDR. Previous anti-tuberculosis treatment of more than 1 month was strongly associated with the development of MDR-TB (adjusted OR 4.8, 95% CI 2.5-9.1). CONCLUSION The first national drug resistance survey in Myanmar revealed 4% and 15.5% MDR-TB among new and retreatment cases, respectively. Previous antituberculosis treatment was an important risk factor for MDR-TB. Continuous monitoring of drug resistance trends is needed
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Affiliation(s)
- T Ti
- National Tuberculosis Programme, Yangon General Hospital Extension Compound, Myanmar.
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Hao F, Lwin T, Bruckard WJ, Woodcock JT. Determination of aliphatic amines in mineral flotation liquors and reagents by high-performance liquid chromatography after derivatization with 4-chloro-7-nitrobenzofurazan. J Chromatogr A 2004; 1055:77-85. [PMID: 15560482 DOI: 10.1016/j.chroma.2004.08.130] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.0] [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: 11/15/2022]
Abstract
The method described here fulfils the need for a suitable analytical method to determine the concentrations of single and mixed aliphatic amines in the range from hexylamine (C6) to octadecylamine (C18) in flotation test solutions and in commercial flotation collectors. Amines do not have a UV-vis spectrum in aqueous solution but by reacting an amine-containing solution with 4-chloro-7-nitrobenzofurazan solution (chloro-NBD), derivatized products (amino-NBDs) are formed which have absorbance maxima at 470nm. Excess chloro-NBD and the amino-NBDs can be separated from each other by high-performance liquid chromatography (HPLC) and their concentrations measured with a UV-vis detector. Important variables in the derivatization stage are pH, temperature, chloro-NBD concentration, and reaction time, all of which interact with each other. A three-stage statistical procedure was used to determine the optimum conditions. In each stage, an 8-test design was used in which a high and low limit was set for each variable, and the chromatogram peak area of the derived amino-NBD was measured. The optimum derivatization conditions established were pH 8.9, chloro-NBD concentration 0.20% (w/v), temperature 70 degrees C, and reaction time 60 min. Optimum elution conditions for chromatography were an eluent containing 80% (v/v) acetonitrile in aqueous solution containing 40mM acetic acid at pH 4.5. With a flow rate of 2.0 ml/min, dodecylamine had a retention time of about 3 min, whereas octadecylamine had a retention time of 44 min. Straight-line calibration curves were obtained up to at least 200 ppm of amine in solution. The lower limit of detection was estimated to be 0.05 microM (10ppb) with a signal to noise ratio of 3. No interfering substances were found. The method was successfully applied to the analysis of solutions from an actual flotation test and to a solid commercial amine.
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Affiliation(s)
- F Hao
- CSIRO Minerals, Clayton South, Vic 3169, Australia.
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Mason DP, Pattarapotikul J, Chindanond D, Supavej S, Wongcharoenyong S, Lwin T, Silachamroon U, Looareesuwan S. Malaria in southern Thailand: relationship between parasitaemia and disease. Trans R Soc Trop Med Hyg 2001; 95:418-9. [PMID: 11579887 DOI: 10.1016/s0035-9203(01)90200-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Affiliation(s)
- D P Mason
- Faculty of Tropical Medicine, Mahidol University, Bangkok 10400, Thailand.
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Chaimanee Y, Thein T, Ducrocq S, Soe AN, Benammi M, Tun T, Lwin T, Wai S, Jaeger JJ. A lower jaw of Pondaungia cotteri from the Late Middle Eocene Pondaung Formation (Myanmar) confirms its anthropoid status. Proc Natl Acad Sci U S A 2000; 97:4102-5. [PMID: 10760279 PMCID: PMC18163 DOI: 10.1073/pnas.97.8.4102] [Citation(s) in RCA: 62] [Impact Index Per Article: 2.6] [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: 11/18/2022] Open
Abstract
Pondaungia cotteri is the largest primate known from the Late Middle Eocene Pondaung Formation, Myanmar. Its taxonomic status has been the subject of much debate because of the fragmentary nature of its remains. Initially described as an anthropoid, some authors recently have associated it with adapid primates. These debates have been fueled not only by the incompleteness of the fossils attributed to Pondaungia but also by the reticence of many authors to regard Asia as an important evolutionary theater for Eocene anthropoids. During the November 1998 Myanmar-French Pondaung Expedition, a right lower jaw was discovered that yields the most nearly complete dentition of Pondaungia cotteri ever found: it shows the complete horizontal ramus, alveoli for the second incisor and canine, three premolars, and three molars. The symphysis showed all characteristics of anthropoids but was unfused. The canine root is large, the first premolar is absent, and the second premolar is single-rooted, reduced, and oblique in the tooth row, as in anthropoids. The premolars show a reduced mesio-distal length compared with the tooth row, and their morphology is very similar to that of Amphipithecus mogaungensis. Therefore, the two Pondaung taxa appear to be closely related to each other, with Siamopithecus as their sister taxon.
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Affiliation(s)
- Y Chaimanee
- Department of Mineral Resources, Geological Survey Division, Paleontological Section, Rama VI Road, Bangkok 10400, Thailand
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Jaeger J, Thein T, Benammi M, Chaimanee Y, Soe AN, Lwin T, Tun T, Wai S, Ducrocq S. A new primate from the Middle Eocene of Myanmar and the Asian early origin of anthropoids. Science 1999; 286:528-30. [PMID: 10521348 DOI: 10.1126/science.286.5439.528] [Citation(s) in RCA: 71] [Impact Index Per Article: 2.8] [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: 11/02/2022]
Abstract
A new genus and species of anthropoid primate, Bahinia pondaungensis gen. et sp. nov., is described from the Yashe Kyitchaung locality in the Late Middle Eocene Pondaung Formation (Myanmar). It is related to Eosimias, but it is represented by more complete remains, including upper dentition with associated lower jaw fragment. It is interpreted as a new representative of the family Eosimiidae, which corresponds to the sister group of the Amphipithecidae and of all other anthropoids. Eosimiidae are now recorded from three distinct Middle Eocene localities in Asia, giving support to the hypothesis of an Asian origin of anthropoids.
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Affiliation(s)
- J Jaeger
- Institut des Science de l'Evolution, Université Montpellier-II, case 064, 34095 Montpellier cedex 5, France
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Lwin T, Mra R, Aye KT, Oo K, Thein S, Moe K. HIV transmission in sexual partners of persons with HIV/AIDS attending the Infectious Diseases Hospital, Yangon. Southeast Asian J Trop Med Public Health 1999; 30:251-6. [PMID: 10774688] [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] [Subscribe] [Scholar Register] [Indexed: 02/16/2023]
Abstract
A study was conducted in the Infectious Diseases Hospital, Yangon, for one year from August 1996 to 1997, to assess the extent and the factors related to HIV transmission among sexual partners of HIV/AIDS cases. It was a cross-sectional comparative study on 67 (61 males, 6 females) HIV positive individuals with or without AIDS, and their sexual partners. Separate interviews of index cases and partners were done, and clinical examination and laboratory tests for HIV and sexually transmitted diseases (STDs) were performed. HIV transmission was found in 41.8% of the partners. Male-to-female transmission was 39.3% (n=61) and female to male transmission was 66.7% (n=6), Seven and one half percent of the partners were suffering from AIDS. There were 4 (6.6%) pregnant mothers and 1 (25%) was HIV positive. Though 75% of the partners did not use condoms during their married life, HIV transmission was significantly reduced in the condom users (odds ratio (OR) = 0.18, 95% confidence interval (CI) 0.02-0.98 p = < 0.05). The seropositive men who were less than 30 years of age had greater HIV transmission (OR = 5.67, 95% CI 1.13-36.46). However, socio-demographic factors, number of marital partners and age of first sex partners, duration of marriage, number of sexual relationships between these couples, duration of HIV positivity and AIDS infection, immunological status of the index group and STD positivity among partners had no significant association with the transmission of HIV. This study demonstrated that the transmission of HIV was high among the sexual partners of persons with HIV infection. It also highlighted the requirement of effective counseling and preventive measures against HIV infection among the couples.
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Affiliation(s)
- T Lwin
- Department of Medical Research, Yangon, Myanmar
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Kato Y, Morikawa A, Sugiyama T, Koide N, Jiang GZ, Lwin T, Yoshida T, Yokochi T. Augmentation of lipopolysaccharide-induced thymocyte apoptosis by interferon-gamma. Cell Immunol 1997; 177:103-8. [PMID: 9178636 DOI: 10.1006/cimm.1997.1103] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.8] [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: 02/04/2023]
Abstract
The role of interferon (IFN)-gamma on thymocyte apoptosis in response to lipopolysaccharide (LPS) was investigated. The administration of LPS into mice induced marked apoptosis of thymocytes in vivo, but the simultaneous injection of anti-IFN-gamma antibody with LPS completely prevented thymocyte apoptosis. Pretreatment of mice with IFN-gamma markedly enhanced LPS-induced thymocyte apoptosis. Thymocyte apoptosis augmented by IFN-gamma occurred in the thymic cortex, and target cells undergoing apoptosis were CD4+8+ immature thymocytes. IFN-gamma itself did not induce thymocyte apoptosis in vivo and in vitro. IFN-gamma exhibited no synergistic action with effector molecules, such as tumor necrosis factor (TNF)-alpha and glucocorticoids. Further, it was shown that IFN-gamma did not enhance the susceptibility of thymocytes to apoptosis. Pretreatment of mice with IFN-gamma significantly augmented the serum TNF-alpha level and the serum cortisol level in response to LPS. Therefore, we suggest that IFN-gamma might augment LPS-induced thymocyte apoptosis through elevating serum TNF-alpha and cortisol levels.
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Affiliation(s)
- Y Kato
- Department of Microbiology and Immunology, Aichi Medical University, Nagakute, Japan
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Paeng N, Kido N, Kato Y, Sugiyama T, Koide N, Naruse M, Jiang GZ, Lwin T, Yoshida T, Yokochi T. Marked reduction of mouse peritoneal CD5+ B cells by intraperitoneal administration of lipopolysaccharide. Infect Immun 1997; 65:122-6. [PMID: 8975901 PMCID: PMC174565 DOI: 10.1128/iai.65.1.122-126.1997] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [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: 02/03/2023] Open
Abstract
Intraperitoneal administration of lipopolysaccharide to mice induced a marked reduction of CD5+ B cells in the peritoneal cavity. The reduction was not induced by intravenous, subcutaneous, or oral administration of lipopolysaccharide. The reduction continued for about 10 days after the injection, and the CD5+ B-cell count recovered to the normal state about 14 days after the injection. The reduction of peritoneal CD5+ B cells might be caused by apoptotic cell death. Injection of lipopolysaccharide did not result in production of antibody to lipopolysaccharide. On the other hand, intraperitoneal injection of heat-killed bacteria did not induce a reduction of peritoneal CD5+ B cells and elicited the definite production of antibody to lipopolysaccharide.
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Affiliation(s)
- N Paeng
- Department of Microbiology and Immunology, Aichi Medical University, Nagakute, Japan
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Nagase F, Lwin T, Nakashima I. Cytokine-independent proliferation of IL-2-nonproducing CTL clones in association with high TCR-signal transduction responses. Microbiol Immunol 1996; 40:505-11. [PMID: 8865156 DOI: 10.1111/j.1348-0421.1996.tb01101.x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [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: 02/02/2023]
Abstract
Alloreactive CTL clone D2-23 proliferated in response to antigenic cells without IL-2 production. Among subclones of D2-23, the F1 but not F2 clone proliferated in response to soluble aCD3 or PMA, although both clones proliferated in response to immobilized aCD3, antigenic cells or soluble aCD3 plus costimulatory cells. The difference in responsiveness between F1 and F2 was not caused by distinct expression of CD3 or Fe receptors. Cyclosporin A, which totally blocks IL-2 production of Th1 cells, barely or only partially inhibited PMA- or aCD3-induced proliferation of F1. F1 did not produce cytokines for proliferation of F2 in response to soluble aCD3. Tyrosine phosphorylation developed for various proteins of F1 and F2 at the levels apparently correlated to the extent of cell proliferation when the cells were stimulated with soluble aCD3 or PMA. The proliferative responsiveness of F1 and F2 to the described stimulators was maintained by stimulation with IL-2 plus antigenic cells, or even IL-2 alone, but was decreased during resting culture or by stimulation with immobilized aCD3. These results show evidence of a new TCR-linked mechanism for CTL proliferation that is independent of costimulatory cell- or cytokine-mediated signaling, but is originally prepared by prior stimulation with IL-2.
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Affiliation(s)
- F Nagase
- Department of Medical Technology, Nagoya University College of Medical Technology, Aichi, Japan
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Lwin T, Nakashima I, Nagase F. Down-regulation of T-cell proliferation in response to soluble anti-CD3 antibodies through development of redirected cytolytic activity eliminating costimulatory cells. Microbiol Immunol 1995; 39:599-606. [PMID: 7494499 DOI: 10.1111/j.1348-0421.1995.tb02248.x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [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: 01/25/2023]
Abstract
CD4+ T-depleted spleen cells (CD8+ T cells) activated by anti-CD3 antibodies (aCD3) suppressed proliferation of CD8+ T-depleted spleen cells (CD4+ T cells) and fresh normal T cells in response to aCD3. Antigen-nonspecific cytolytic activity was induced in splenic CD8+ T cells by stimulation with aCD3 and showed the peak level on day 3, whereas cytolytic activity induced in CD4+ T cells was weak. Intact Ig but not F(ab')2 of aCD3 induced and mediated cytolytic activity. Correspondingly the cytolytic activity induced by aCD3 was directed against target cells bearing Ig-binding Fc-receptor activity and cytolysis was inhibited by the addition of free Ig into the assay system. We showed that aCD3-activated T cells carried a high level of aCD3 on their surface at the time after the peak proliferation when they attained high cytolytic activity. This raised the possibility that the anti-CD3-induced aCD3-redirected cytolytic activity eliminated Fc-receptor-bearing costimulatory cells in the culture for down-regulation of the T-cell proliferation. This view was supported by partial restoration of anti-CD3-induced low responsiveness of CD8+ T cells by the addition of fresh costimulatory cells. These results suggested a new pathway of down-regulation of T-cell proliferation by aCD3-activated cytolytic CD8+ T cells.
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Affiliation(s)
- T Lwin
- Department of Immunology, Nagoya University School of Medicine, Aichi, Japan
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Lwin T, Nakashima I, Nagase F. TCR-independent induction of low responsiveness by chemically fixed cells in alloreactive CTL clones and its prevention through cognate cell-cell interaction. Microbiol Immunol 1995; 39:509-15. [PMID: 8569536 DOI: 10.1111/j.1348-0421.1995.tb02235.x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [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: 01/31/2023]
Abstract
We established BALB/c-derived CD8+ CTL clones D2-22 (V beta 6+), D2-23 (V beta 8+) and D2-24 (V beta 8+) specific for B10.D2 minor H antigen. D2-22 and D2-23 proliferated without producing IL-2 in response to X-ray-irradiated antigenic cells, Con A, aCD3, PMA and IL-2. Paraformaldehyde-fixed antigenic spleen cells neither induced proliferation in the presence of costimulatory cells nor inhibited responses to irradiated antigenic cells added simultaneously. Unlike the previously reported results with IL-2-producing CTL clones and Th1 clones, the fixed antigenic cells failed to induce antigen-specific unresponsiveness in these IL-2-non-producing CTL clones. Instead, the responsiveness of these clones to fresh stimulation was found to be reduced severely after 2 days in the culture added with either antigenic or syngeneic fixed cells. Induction of their antigen-nonspecific low responsiveness by the fixed cells was prevented by adding irradiated syngeneic cells into the culture or even by increasing the concentration of responder D2-23 cells. Close contact of D2-23 and irradiated syngeneic cells was required to prevent the reduction of the responsiveness, although this cognate cell-cell interaction could be replaced by exogenously added IL-2 or PMA. Cytolytic and tumor cell growth inhibitory activities of D2-23 were also reduced by incubation with the fixed cells, which was prevented by the addition of irradiated syngeneic cells. These findings showed the unique properties of IL-2-nonproducing CTL clones in signal requirements for maintaining normal responsiveness for proliferation and cytolytic activity.
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Affiliation(s)
- T Lwin
- Department of Immunology, Nagoya University School of Medicine, Aichi, Japan
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Kato M, Pu MY, Isobe K, Iwamoto T, Nagase F, Lwin T, Zhang YH, Hattori T, Yanagita N, Nakashima I. Characterization of the immunoregulatory action of saikosaponin-d. Cell Immunol 1994; 159:15-25. [PMID: 7954839 DOI: 10.1006/cimm.1994.1291] [Citation(s) in RCA: 47] [Impact Index Per Article: 1.6] [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: 01/28/2023]
Abstract
The immunoregulatory action of saikosaponin-d (SSd), which was isolated from the root of Bupleurum falcatum L. and has a steroid-like structure, was examined on splenic T lymphocytes of C57BL/6 mice. SSd displayed a definite action in vitro to bidirectionally control the growth response of T lymphocytes stimulated by concanavalin A, anti-CD3 monoclonal antibody, and calcium ionophore A23187 plus phorbol 12-myristate 13-acetate. Low concentrations (1-3 micrograms/ml) of SSd upregulated the responses to suboptimum stimuli of agonists, particularly during the relatively late stage of the responses, whereas it downregulated the responses to supraoptimal stimuli. Under appropriate experimental conditions, SSd promoted interleukin-2 (IL-2) production and IL-2 receptor expression. It also accelerated c-fos gene transcription, but it did not modulate the level of tyrosine phosphorylation of cellular proteins. We concluded from these results that SSd uniquely modulates T lymphocyte function and that at least one target of the action of SSd is located at or before the step of c-fos gene transcription and after T-cell receptor/CD3-mediated protein tyrosine kinase activation.
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Affiliation(s)
- M Kato
- Department of Immunology, Nagoya University School of Medicine, Japan
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Zhang YH, Isobe K, Nagase F, Lwin T, Kato M, Hamaguchi M, Yokochi T, Nakashima I. Glycyrrhizin as a promoter of the late signal transduction for interleukin-2 production by splenic lymphocytes. Immunol Suppl 1993; 79:528-34. [PMID: 8406577 PMCID: PMC1421919] [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: 01/30/2023]
Abstract
Cellular and molecular mechanisms of the immunomodulatory action of glycyrrhizin (GL) were studied. We demonstrated that GL displays a unique action to prolong the duration of the T-cell receptor-mediated in vitro splenic T-lymphocyte growth response to anti-CD3 monoclonal antibody (mAb) or concanavalin A (Con A) through enhancement of interleukin-2 (IL-2) secretion and IL-2 receptor (IL-2R) expression. The augmentation by GL of IL-2 production was also found in spleen cells stimulated with A23187 plus phorbol 12-myristate 13-acetate (PMA), suggesting that GL primarily affects some post-receptor stage of the signal transduction. We also found that the time of GL action for promoting IL-2 production and growth response was 2 hr or more after receptor activation. Correspondingly, GL did not augment the anti-CD3 mAb or Con A-mediated protein tyrosine phosphorylation and c-fos transcription. We concluded from these results that GL acts as a promoter of the late signal transduction of T lymphocytes for IL-2 production.
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Affiliation(s)
- Y H Zhang
- Department of Immunology, Nagoya University School of Medicine, Japan
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Nakashima I, Yoshida T, Zhang YH, Pu MY, Taguchi R, Ikezawa H, Isobe K, Iwamoto T, Kato M, Lwin T. T Cell maturation stage-linked heterogeneity of the glycosylphosphatidylinositol membrane anchor of Thy-1. Immunobiology 1992; 185:466-74. [PMID: 1360444 DOI: 10.1016/s0171-2985(11)80088-4] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [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: 11/16/2022]
Abstract
We showed that some of Thy-1 molecules on murine thymocytes are resistant to phosphatidylinositol-specific phospholipase C (PI-PLC) derived from Bacillus thuringiensis. Both immature thymocytes with low CD3 expression and mature thymic T lymphocytes with high CD3 expression carried the PI-PLC-resistant Thy-1, and the PI-PLC-sensitivity of Thy-1 extensively varied among thymocyte subpopulations. In contrast, the same PI-PLC fully hydrolysed the anchor of Thy-1 on peripheral T lymphocytes. When the latter cells were activated with mitogen in vitro, however, some Thy-1 on them became resistant to PI-PLC. We then found that virtually all Thy-1 molecules on thymocytes became sensitive to PI-PLC when they were treated with hydroxylamine that should cleave ester-linked lipids. The result ruled out the possibility that the PI-PLC-resistant Thy-1 had a transmembranous peptide sequence, and suggested the presence of an additional fatty acyl group on the inositol ring of the Thy-1 anchor. In addition, the molecular size of the PI-PLC-resistant membrane-bound Thy-1 was only marginally larger than that of the PI-PLC-sensitive solubilized Thy-1 in detergent-partitioning SDS-PAGE analysis.
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Affiliation(s)
- I Nakashima
- Department of Immunology, Nagoya University School of Medicine, Aichi, Japan
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Young K, Maritz J, Lwin T. Empirical Bayes Methods. J R Stat Soc Ser C Appl Stat 1992. [DOI: 10.2307/2348097] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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Bagghi P, Maritz JS, Lwin T. Empirical Bayes Methods. J Am Stat Assoc 1991. [DOI: 10.2307/2289739] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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Koh P, Lwin T, Albrecht D. Analysis of weight frequency particle size distributions: With special application to bimodal floc size distributions in shear-flocculation. POWDER TECHNOL 1989. [DOI: 10.1016/0032-5910(89)80032-4] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Lwin T, Martin PJ. Probits of mixtures. Biometrics 1989; 45:721-32. [PMID: 2790119] [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: 01/02/2023]
Abstract
The tolerances of individuals (insects, parasites) in a population have a frequency or probability distribution called a tolerance distribution. Many tolerance distributions in bioassay studies can be the result of a rather heterogeneous population of individuals and can often be modelled as a mixture of a number of standard unimodal distributions. A probit analysis can be generalized to the case where the tolerance distribution is a mixture of location and scale parameter distributions. In this article, the existence and determination of the maximum likelihood estimates are investigated. An expectation-maximization (EM) algorithm for probits of mixtures is developed and it is shown that by application of the EM algorithm, the problem of probits of mixtures can be separated into a series of probits of individual component tolerance distributions.
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Affiliation(s)
- T Lwin
- Division of Mathematics and Statistics, CSIRO, Clayton, Victoria, Australia
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Lwin T, Maritz JS. Empirical Bayes approach to multiparameter estimation: with special reference to multinomial distribution. ANN I STAT MATH 1989. [DOI: 10.1007/bf00049111] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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Abstract
The incidence of unilobar or bilobar pathology is disproportionately high in patients with duplication of the gallbladder. The results of ultrasound and Tc-99m DISIDA studies in one case of gallbladder duplication are presented. An awareness of gallbladder anomalies may improve the accuracy of hepatobiliary imaging by eliminating some false-negative results.
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Martin PJ, Anderson N, Lwin T, Nelson G, Morgan TE. The association between frequency of thiabendazole treatment and the development of resistance in field isolates of Ostertagia spp. of sheep. Int J Parasitol 1984; 14:177-81. [PMID: 6735581 DOI: 10.1016/0020-7519(84)90046-8] [Citation(s) in RCA: 40] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
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Fletcher S, Halliday C, Gates D, Westcott M, Lwin T, Nelson G. The response of some nucleation/growth processes to triangular scans of potential. ACTA ACUST UNITED AC 1983. [DOI: 10.1016/s0022-0728(83)80627-5] [Citation(s) in RCA: 282] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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Lwin T. [A Bayesian Analysis of the Linear Calibration Problem]: Discussion. Technometrics 1981. [DOI: 10.2307/1268221] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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Probert AJ, Lwin T. Fasciola hepatica: the subcellular distribution and kinetic and electrophoretic properties of malate dehydrogenase. Exp Parasitol 1977; 41:89-94. [PMID: 838035 DOI: 10.1016/0014-4894(77)90133-3] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
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Probert AJ, Lwin T. Kinetic properties, and location of nonspecific phosphomonoesterases in subcellular fractions of fasciola hepatica. Exp Parasitol 1974; 35:253-61. [PMID: 4821450 DOI: 10.1016/0014-4894(74)90030-7] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
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