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de Vrij N, Pollmann J, Rezende AM, Ibarra-Meneses AV, Pham TT, Hailemichael W, Kassa M, Bogale T, Melkamu R, Yeshanew A, Mohammed R, Diro E, Maes I, Domagalska MA, Landuyt H, Vogt F, van Henten S, Laukens K, Cuypers B, Meysman P, Beyene H, Sisay K, Kibret A, Mersha D, Ritmeijer K, van Griensven J, Adriaensen W. Persistent T cell unresponsiveness associated with chronic visceral leishmaniasis in HIV-coinfected patients. Commun Biol 2024; 7:524. [PMID: 38702419 DOI: 10.1038/s42003-024-06225-2] [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] [Received: 01/05/2023] [Accepted: 04/22/2024] [Indexed: 05/06/2024] Open
Abstract
A large proportion of HIV-coinfected visceral leishmaniasis (VL-HIV) patients exhibit chronic disease with frequent VL recurrence. However, knowledge on immunological determinants underlying the disease course is scarce. We longitudinally profiled the circulatory cellular immunity of an Ethiopian HIV cohort that included VL developers. We show that chronic VL-HIV patients exhibit high and persistent levels of TIGIT and PD-1 on CD8+/CD8- T cells, in addition to a lower frequency of IFN-γ+ TIGIT- CD8+/CD8- T cells, suggestive of impaired T cell functionality. At single T cell transcriptome and clonal resolution, the patients show CD4+ T cell anergy, characterised by a lack of T cell activation and lymphoproliferative response. These findings suggest that PD-1 and TIGIT play a pivotal role in VL-HIV chronicity, and may be further explored for patient risk stratification. Our findings provide a strong rationale for adjunctive immunotherapy for the treatment of chronic VL-HIV patients to break the recurrent disease cycle.
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Affiliation(s)
- Nicky de Vrij
- Clinical Immunology Unit, Department of Clinical Sciences, Institute of Tropical Medicine, 2000, Antwerp, Belgium
- Adrem Data Lab, Department of Computer Science, University of Antwerp, 2020, Antwerp, Belgium
| | - Julia Pollmann
- Department of Medical Oncology, University Hospital Heidelberg, National Center for Tumor Diseases (NCT) Heidelberg, 69120, Heidelberg, Germany
| | - Antonio M Rezende
- Department of Microbiology, Aggeu Magalhães Institute-FIOCRUZ/PE, Recife, Brazil
| | - Ana V Ibarra-Meneses
- Département de Pathologie et Microbiologie, Faculté de Médecine Vétérinaire, Université de Montréal, Saint-Hyacinthe, QC, Canada
| | - Thao-Thy Pham
- Clinical Immunology Unit, Department of Clinical Sciences, Institute of Tropical Medicine, 2000, Antwerp, Belgium
| | - Wasihun Hailemichael
- Department of Immunology and Molecular Biology, Faculty of Biomedical Sciences, University of Gondar, Gondar, Ethiopia
| | - Mekibib Kassa
- Leishmaniasis Research and Treatment Centre, University of Gondar, Gondar, Ethiopia
| | - Tadfe Bogale
- Leishmaniasis Research and Treatment Centre, University of Gondar, Gondar, Ethiopia
| | - Roma Melkamu
- Leishmaniasis Research and Treatment Centre, University of Gondar, Gondar, Ethiopia
| | - Arega Yeshanew
- Leishmaniasis Research and Treatment Centre, University of Gondar, Gondar, Ethiopia
| | - Rezika Mohammed
- Leishmaniasis Research and Treatment Centre, University of Gondar, Gondar, Ethiopia
| | - Ermias Diro
- Leishmaniasis Research and Treatment Centre, University of Gondar, Gondar, Ethiopia
| | - Ilse Maes
- Molecular Parasitology Unit, Department of Biomedical Sciences, Institute of Tropical Medicine, 2000, Antwerp, Belgium
| | - Malgorzata A Domagalska
- Molecular Parasitology Unit, Department of Biomedical Sciences, Institute of Tropical Medicine, 2000, Antwerp, Belgium
| | - Hanne Landuyt
- Clinical Trial Unit, Department of Clinical Sciences, Institute of Tropical Medicine, 2000, Antwerp, Belgium
| | - Florian Vogt
- National Centre for Epidemiology and Population Health, The Australian National University, Canberra, 2601, Australia
- The Kirby Institute, University of New South Wales, Sydney, 2052, Australia
- Unit of Neglected Tropical Diseases, Department of Clinical Sciences, Institute of Tropical Medicine, 2000, Antwerp, Belgium
| | - Saskia van Henten
- Unit of Neglected Tropical Diseases, Department of Clinical Sciences, Institute of Tropical Medicine, 2000, Antwerp, Belgium
| | - Kris Laukens
- Adrem Data Lab, Department of Computer Science, University of Antwerp, 2020, Antwerp, Belgium
| | - Bart Cuypers
- Adrem Data Lab, Department of Computer Science, University of Antwerp, 2020, Antwerp, Belgium
| | - Pieter Meysman
- Adrem Data Lab, Department of Computer Science, University of Antwerp, 2020, Antwerp, Belgium
| | | | | | | | | | | | - Johan van Griensven
- Unit of Neglected Tropical Diseases, Department of Clinical Sciences, Institute of Tropical Medicine, 2000, Antwerp, Belgium
| | - Wim Adriaensen
- Clinical Immunology Unit, Department of Clinical Sciences, Institute of Tropical Medicine, 2000, Antwerp, Belgium.
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Pollenus E, Prenen F, Possemiers H, Knoops S, Mitera T, Lamote J, De Visscher A, Vandermosten L, Pham TT, Matthys P, Van den Steen PE. Aspecific binding of anti-NK1.1 antibodies on myeloid cells in an experimental model for malaria-associated acute respiratory distress syndrome. Malar J 2024; 23:110. [PMID: 38637828 PMCID: PMC11025177 DOI: 10.1186/s12936-024-04944-9] [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] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2023] [Accepted: 04/12/2024] [Indexed: 04/20/2024] Open
Abstract
BACKGROUND Conventional natural killer (cNK) cells play an important role in the innate immune response by directly killing infected and malignant cells and by producing pro- and anti-inflammatory cytokines. Studies on their role in malaria and its complications have resulted in conflicting results. METHODS Using the commonly used anti-NK1.1 depletion antibodies (PK136) in an in-house optimized experimental model for malaria-associated acute respiratory distress syndrome (MA-ARDS), the role of cNK cells was investigated. Moreover, flow cytometry was performed to characterize different NK cell populations. RESULTS While cNK cells were found to be dispensable in the development of MA-ARDS, the appearance of a NK1.1+ cell population was observed in the lungs upon infection despite depletion with anti-NK1.1. Detailed characterization of the unknown population revealed that this population consisted of a mixture of monocytes and macrophages that bind the anti-NK1.1 antibody in an aspecific way. This aspecific binding may occur via Fcγ receptors, such as FcγR4. In contrast, in vivo depletion using anti-NK1.1 antibodies was proved to be specific for cNK cells. CONCLUSION cNK cells are dispensable in the development of experimental MA-ARDS. Moreover, careful flow cytometric analysis, with a critical mindset in relation to potential aspecific binding despite the use of commercially available Fc blocking reagents, is critical to avoid misinterpretation of the results.
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Affiliation(s)
- Emilie Pollenus
- Laboratory of Immunoparasitology, Department of Microbiology, Immunology and Transplantation, Rega Institute for Medical Research, KU Leuven, Leuven, Belgium
| | - Fran Prenen
- Laboratory of Immunoparasitology, Department of Microbiology, Immunology and Transplantation, Rega Institute for Medical Research, KU Leuven, Leuven, Belgium
| | - Hendrik Possemiers
- Laboratory of Immunoparasitology, Department of Microbiology, Immunology and Transplantation, Rega Institute for Medical Research, KU Leuven, Leuven, Belgium
| | - Sofie Knoops
- Laboratory of Immunoparasitology, Department of Microbiology, Immunology and Transplantation, Rega Institute for Medical Research, KU Leuven, Leuven, Belgium
| | - Tania Mitera
- Laboratory of Immunobiology, Department of Microbiology, Immunology and Transplantation, Rega Institute for Medical Research, KU Leuven, Leuven, Belgium
| | - Jochen Lamote
- Laboratory for Molecular Cancer Biology, Department of Oncology, VIB, KU Leuven, Leuven, Belgium
| | - Amber De Visscher
- Laboratory of Immunobiology, Department of Microbiology, Immunology and Transplantation, Rega Institute for Medical Research, KU Leuven, Leuven, Belgium
| | - Leen Vandermosten
- Laboratory of Immunoparasitology, Department of Microbiology, Immunology and Transplantation, Rega Institute for Medical Research, KU Leuven, Leuven, Belgium
| | - Thao-Thy Pham
- Laboratory of Immunoparasitology, Department of Microbiology, Immunology and Transplantation, Rega Institute for Medical Research, KU Leuven, Leuven, Belgium
- Currently at Clinical Immunology Unit, Department of Clinical Sciences, Institute of Tropical Medicine Antwerp, Antwerp, Belgium
| | - Patrick Matthys
- Laboratory of Immunobiology, Department of Microbiology, Immunology and Transplantation, Rega Institute for Medical Research, KU Leuven, Leuven, Belgium
| | - Philippe E Van den Steen
- Laboratory of Immunoparasitology, Department of Microbiology, Immunology and Transplantation, Rega Institute for Medical Research, KU Leuven, Leuven, Belgium.
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Tran NT, Phan TNT, Pham TT, Le TT, Le HM, Nguyen DT, Lam AN, Pham TT, Le HT, Dang NB, Tran KC, Tran VD. Urban-rural disparities in acceptance of human papillomavirus vaccination among women in Can Tho, Vietnam. Ann Ig 2023; 35:641-659. [PMID: 37313797 DOI: 10.7416/ai.2023.2575] [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] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Background In Vietnam, cervical cancer is a significant public health concern for women. Unfortunately, despite the availability of the HPV vaccine, low vaccination rates persist. Objectives This study investigates the discrepancy between urban and rural areas in the willingness to receive HPV vaccination with or without fees. Methods A cross-sectional study was conducted on a sample of 648 women aged between 15 and 49, living in two urban and two rural Vietnamese districts of Can Tho, between May and December 2021. Results The overall vaccination rate was 4%, with urban women having a higher rate of 4.9% compared to rural women at 3.1%. Among unvaccinated women, those from rural areas expressed a significantly higher desire to receive the free vaccine (91.4%) than urban women (84.4%). However, the intention to vaccinate declined when rural women and urban women were advised to pay the cost (63.4% and 57.1%, respectively). A strong correlation was found between a positive attitude and intention for vaccination, irrespective of its price or free availability. Education and access to information about the HPV vaccine were also identified as the most significant factors influencing the intention to vaccination among urban and rural women. Conclusion The low HPV vaccination rates among women aged 15-49 living in both urban and rural regions of Vietnam are a notable public health concern. These outcomes emphasize the critical need for effective programs of vaccine laterization, as an introduction to the offer of affordable and accessible HPV vaccines for women in Can Tho, Vietnam.
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Affiliation(s)
- N T Tran
- Department of Environment and Occupational Health, Faculty of Public Health, Can Tho University of Medicine and Pharmacy, Can Tho, Vietnam
| | - T N T Phan
- Department of Environment and Occupational Health, Faculty of Public Health, Can Tho University of Medicine and Pharmacy, Can Tho, Vietnam
| | - T T Pham
- Department of Nutrition and Food Safety, Faculty of Public Health, Can Tho University of Medicine and Pharmacy, Can Tho, Vietnam
| | - T T Le
- Department of Environment and Occupational Health, Faculty of Public Health, Can Tho University of Medicine and Pharmacy, Can Tho, Vietnam
| | - H M Le
- Department of Epidemiology, Faculty of Public Health, Can Tho University of Medicine and Pharmacy, Can Tho, Vietnam
| | - D T Nguyen
- Department of Biostatistics and Demography, Can Tho University of Medicine and Pharmacy, Can Tho, Vietnam
| | - A N Lam
- Department of Epidemiology, Faculty of Public Health, Can Tho University of Medicine and Pharmacy, Can Tho, Vietnam
| | - T T Pham
- Department of Health Organization and Management, Can Tho University of Medicine and Pharmacy, Can Tho, Vietnam
| | - H T Le
- Department of Health Organization and Management, Can Tho University of Medicine and Pharmacy, Can Tho, Vietnam
| | - N B Dang
- Pharmaceutical Biotechnology, Faculty of Pharmacy, Dong Thap Medical College, Dong Thap, Vietnam
| | - K C Tran
- Science in Pharmacy, Faculty of Pharmacy, Dong Thap Medical College, Dong Thap, Vietnam
| | - V D Tran
- Department of Health Organization and Management, Can Tho University of Medicine and Pharmacy, Can Tho, Vietnam
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Pollenus E, Pham TT, Vandermosten L, Robalo Q, Possemiers H, Knoops S, Opdenakker G, Van den Steen PE. Corrigendum: CCR2 Is Dispensable for Disease Resolution but Required for the Restoration of Leukocyte Homeostasis Upon Experimental Malaria-Associated Acute Respiratory Distress Syndrome. Front Immunol 2022; 13:926032. [PMID: 35720305 PMCID: PMC9199370 DOI: 10.3389/fimmu.2022.926032] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2022] [Accepted: 05/16/2022] [Indexed: 12/02/2022] Open
Affiliation(s)
- Emilie Pollenus
- Laboratory of Immunoparasitology, Department of Microbiology, Immunology and Transplantation, Rega Institute for Medical Research, KU Leuven, University of Leuven, Leuven, Belgium
| | - Thao-Thy Pham
- Laboratory of Immunoparasitology, Department of Microbiology, Immunology and Transplantation, Rega Institute for Medical Research, KU Leuven, University of Leuven, Leuven, Belgium
| | - Leen Vandermosten
- Laboratory of Immunoparasitology, Department of Microbiology, Immunology and Transplantation, Rega Institute for Medical Research, KU Leuven, University of Leuven, Leuven, Belgium
| | - Queeny Robalo
- Laboratory of Immunoparasitology, Department of Microbiology, Immunology and Transplantation, Rega Institute for Medical Research, KU Leuven, University of Leuven, Leuven, Belgium
| | - Hendrik Possemiers
- Laboratory of Immunoparasitology, Department of Microbiology, Immunology and Transplantation, Rega Institute for Medical Research, KU Leuven, University of Leuven, Leuven, Belgium
| | - Sofie Knoops
- Laboratory of Immunoparasitology, Department of Microbiology, Immunology and Transplantation, Rega Institute for Medical Research, KU Leuven, University of Leuven, Leuven, Belgium
| | - Ghislain Opdenakker
- Laboratory of Immunobiology, Department of Microbiology, Immunology and Transplantation, Rega Institute for Medical Research, KU Leuven, University of Leuven, Leuven, Belgium
| | - Philippe E Van den Steen
- Laboratory of Immunoparasitology, Department of Microbiology, Immunology and Transplantation, Rega Institute for Medical Research, KU Leuven, University of Leuven, Leuven, Belgium
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Possemiers H, Pham TT, Coens M, Pollenus E, Knoops S, Noppen S, Vandermosten L, D’haese S, Dillemans L, Prenen F, Schols D, Franke-Fayard B, Van den Steen PE. Skeleton binding protein-1-mediated parasite sequestration inhibits spontaneous resolution of malaria-associated acute respiratory distress syndrome. PLoS Pathog 2021; 17:e1010114. [PMID: 34843584 PMCID: PMC8659713 DOI: 10.1371/journal.ppat.1010114] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2021] [Revised: 12/09/2021] [Accepted: 11/15/2021] [Indexed: 11/18/2022] Open
Abstract
Malaria is a hazardous disease caused by Plasmodium parasites and often results in lethal complications, including malaria-associated acute respiratory distress syndrome (MA-ARDS). Parasite sequestration in the microvasculature is often observed, but its role in malaria pathogenesis and complications is still incompletely understood. We used skeleton binding protein-1 (SBP-1) KO parasites to study the role of sequestration in experimental MA-ARDS. The sequestration-deficiency of these SBP-1 KO parasites was confirmed with bioluminescence imaging and by measuring parasite accumulation in the lungs with RT-qPCR. The SBP-1 KO parasites induced similar lung pathology in the early stage of experimental MA-ARDS compared to wildtype (WT) parasites. Strikingly, the lung pathology resolved subsequently in more than 60% of the SBP-1 KO infected mice, resulting in prolonged survival despite the continuous presence of the parasite. This spontaneous disease resolution was associated with decreased inflammatory cytokine expression measured by RT-qPCR and lower expression of cytotoxic markers in pathogenic CD8+ T cells in the lungs of SBP-1 KO infected mice. These data suggest that SBP-1-mediated parasite sequestration and subsequent high parasite load are not essential for the development of experimental MA-ARDS but inhibit the resolution of the disease. Malaria is still a severe global disease with more than 200 million cases and 400 000 deaths each year. Plasmodium falciparum is the species responsible for most malaria deaths globally. The propensity of these parasites to sequester in peripheral vascular beds is assumed to play an important role in disease severity and mortality. Although sequestration has been observed in lungs of malaria patients, its role in the pathogenesis of MA-ARDS, a severe lung complication in malaria, was previously unknown. Therefore, we used sequestration-deficient SBP-1 KO Plasmodium berghei NK65 parasites to study the role of sequestration in experimental MA-ARDS. We observed that MA-ARDS developed similarly in WT and SBP-1 KO infected mice, but the majority of SBP-1 KO-infected mice were able to resolve the lung pathology despite the continuous presence of the parasite. This coincided with a prolonged survival, a decrease in inflammatory cytokine expression and lower expression of cytotoxicity markers in pathogenic CD8+ T cells. These results give important new insights in the role of parasite sequestration in malaria pathology.
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Affiliation(s)
- Hendrik Possemiers
- Laboratory of Immunoparasitology, Department of Microbiology, Immunology and Transplantation, Rega Institute for Medical research, KU Leuven, Belgium
| | - Thao-Thy Pham
- Laboratory of Immunoparasitology, Department of Microbiology, Immunology and Transplantation, Rega Institute for Medical research, KU Leuven, Belgium
- Currently at Clinical Immunology Unit, Department of Clinical Sciences, Institute of Tropical Medicine Antwerp, Belgium
| | - Marion Coens
- Laboratory of Immunoparasitology, Department of Microbiology, Immunology and Transplantation, Rega Institute for Medical research, KU Leuven, Belgium
| | - Emilie Pollenus
- Laboratory of Immunoparasitology, Department of Microbiology, Immunology and Transplantation, Rega Institute for Medical research, KU Leuven, Belgium
| | - Sofie Knoops
- Laboratory of Immunoparasitology, Department of Microbiology, Immunology and Transplantation, Rega Institute for Medical research, KU Leuven, Belgium
| | - Sam Noppen
- Laboratory of Virology and Chemotherapy, Department of Microbiology, Immunology and Transplantation, Rega Institute for Medical research, KU Leuven, Belgium
| | - Leen Vandermosten
- Laboratory of Immunoparasitology, Department of Microbiology, Immunology and Transplantation, Rega Institute for Medical research, KU Leuven, Belgium
| | - Sigrid D’haese
- Laboratory of Immunoparasitology, Department of Microbiology, Immunology and Transplantation, Rega Institute for Medical research, KU Leuven, Belgium
- Currently at Neuro-Aging & Viro-Immunotherapy (NAVI), Vrije Universiteit Brussel (VUB), Brussels, Belgium
| | - Luna Dillemans
- Laboratory of Immunoparasitology, Department of Microbiology, Immunology and Transplantation, Rega Institute for Medical research, KU Leuven, Belgium
| | - Fran Prenen
- Laboratory of Immunoparasitology, Department of Microbiology, Immunology and Transplantation, Rega Institute for Medical research, KU Leuven, Belgium
| | - Dominique Schols
- Laboratory of Virology and Chemotherapy, Department of Microbiology, Immunology and Transplantation, Rega Institute for Medical research, KU Leuven, Belgium
| | | | - Philippe E. Van den Steen
- Laboratory of Immunoparasitology, Department of Microbiology, Immunology and Transplantation, Rega Institute for Medical research, KU Leuven, Belgium
- * E-mail:
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6
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Pollenus E, Pham TT, Vandermosten L, Possemiers H, Knoops S, Opdenakker G, Van den Steen PE. CCR2 Is Dispensable for Disease Resolution but Required for the Restoration of Leukocyte Homeostasis Upon Experimental Malaria-Associated Acute Respiratory Distress Syndrome. Front Immunol 2021; 11:628643. [PMID: 33664739 PMCID: PMC7921736 DOI: 10.3389/fimmu.2020.628643] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [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: 11/12/2020] [Accepted: 12/29/2020] [Indexed: 11/20/2022] Open
Abstract
Malaria complications are often lethal, despite efficient killing of Plasmodium parasites with antimalarial drugs. This indicates the need to study the resolution and healing mechanisms involved in the recovery from these complications. Plasmodium berghei NK65-infected C57BL/6 mice develop malaria-associated acute respiratory distress syndrome (MA-ARDS) at 8 days post infection. Antimalarial treatment was started on this day and resulted in the recovery, as measured by the disappearance of the signs of pathology, in >80% of the mice. Therefore, this optimized model represents an asset in the study of mechanisms and leukocyte populations involved in the resolution of MA-ARDS. C-C chemokine receptor type 2 (CCR2) knock-out mice were used to investigate the role of monocytes and macrophages, since these cells are described to play an important role during the resolution of other inflammatory diseases. CCR2 deficiency was associated with significantly lower numbers of inflammatory monocytes in the lungs during infection and resolution and abolished the increase in non-classical monocytes during resolution. Surprisingly, CCR2 was dispensable for the development and the resolution of MA-ARDS, since no effect of the CCR2 knock-out was observed on any of the disease parameters. In contrast, the reappearance of eosinophils and interstitial macrophages during resolution was mitigated in the lungs of CCR2 knock-out mice. In conclusion, CCR2 is required for re-establishing the homeostasis of pulmonary leukocytes during recovery. Furthermore, the resolution of malaria-induced lung pathology is mediated by unknown CCR2-independent mechanisms.
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Affiliation(s)
- Emilie Pollenus
- Laboratory of Immunoparasitology, Department of Microbiology, Immunology and Transplantation, Rega Institute for Medical Research, KU Leuven, University of Leuven, Leuven, Belgium
| | - Thao-Thy Pham
- Laboratory of Immunoparasitology, Department of Microbiology, Immunology and Transplantation, Rega Institute for Medical Research, KU Leuven, University of Leuven, Leuven, Belgium
| | - Leen Vandermosten
- Laboratory of Immunoparasitology, Department of Microbiology, Immunology and Transplantation, Rega Institute for Medical Research, KU Leuven, University of Leuven, Leuven, Belgium
| | - Hendrik Possemiers
- Laboratory of Immunoparasitology, Department of Microbiology, Immunology and Transplantation, Rega Institute for Medical Research, KU Leuven, University of Leuven, Leuven, Belgium
| | - Sofie Knoops
- Laboratory of Immunoparasitology, Department of Microbiology, Immunology and Transplantation, Rega Institute for Medical Research, KU Leuven, University of Leuven, Leuven, Belgium
| | - Ghislain Opdenakker
- Laboratory of Immunobiology, Department of Microbiology, Immunology and Transplantation, Rega Institute for Medical Research, KU Leuven, University of Leuven, Leuven, Belgium
| | - Philippe E Van den Steen
- Laboratory of Immunoparasitology, Department of Microbiology, Immunology and Transplantation, Rega Institute for Medical Research, KU Leuven, University of Leuven, Leuven, Belgium
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Pham TT, Lamb TJ, Deroost K, Opdenakker G, Van den Steen PE. Hemozoin in Malarial Complications: More Questions Than Answers. Trends Parasitol 2020; 37:226-239. [PMID: 33223096 DOI: 10.1016/j.pt.2020.09.016] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2020] [Revised: 09/29/2020] [Accepted: 09/29/2020] [Indexed: 02/07/2023]
Abstract
Plasmodium parasites contain various virulence factors that modulate the host immune response. Malarial pigment, or hemozoin (Hz), is an undegradable crystalline product of the hemoglobin degradation pathway in the parasite and possesses immunomodulatory properties. An association has been found between Hz accumulation and severe malaria, suggesting that the effects of Hz on the host immune response may contribute to the development of malarial complications. Although the immunomodulatory roles of Hz have been widely investigated, many conflicting data exist, likely due to the variability between experimental set-ups and technical limitations of Hz generation and isolation methods. Here, we critically assess the potential immunomodulatory effects of Hz, its role in malarial complications, and its potential effects after parasite clearance.
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Affiliation(s)
- Thao-Thy Pham
- Laboratory of Immunoparasitology, Department of Microbiology, Immunology and Transplantation, Rega Institute for Medical Research, KU Leuven, 3000 Leuven, Belgium
| | - Tracey J Lamb
- Department of Pathology, University of Utah, Salt Lake City, UT 84112, USA
| | - Katrien Deroost
- Malaria Immunology Laboratory, The Francis Crick Institute, London, UK
| | - Ghislain Opdenakker
- Laboratory of Immunobiology, Department of Microbiology, Immunology and Transplantation, Rega Institute for Medical Research, KU Leuven, 3000 Leuven, Belgium
| | - Philippe E Van den Steen
- Laboratory of Immunoparasitology, Department of Microbiology, Immunology and Transplantation, Rega Institute for Medical Research, KU Leuven, 3000 Leuven, Belgium.
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Nguyen TAH, Ngo HH, Guo WS, Nguyen THH, Soda S, Vu ND, Bui TKA, Vo TDH, Bui XT, Nguyen TT, Pham TT. White hard clam (Meretrix lyrata) shells media to improve phosphorus removal in lab-scale horizontal sub-surface flow constructed wetlands: Performance, removal pathways, and lifespan. Bioresour Technol 2020; 312:123602. [PMID: 32506045 DOI: 10.1016/j.biortech.2020.123602] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/21/2020] [Revised: 05/26/2020] [Accepted: 05/27/2020] [Indexed: 06/11/2023]
Abstract
This work examined the phosphorus (P) removal from the synthetic pretreated swine wastewater using lab-scale horizontal sub-surface flow constructed wetlands (HSSF-CWs). White hard clam (Meretrix lyrata) shells (WHC) and Paspalum atratum were utilized as substrate and plant, respectively. The focus was placed on treatment performance, removal mechanisms and lifespan of the HSSF-CWs. Results indicated that WHC-based HSSF-CW with P. atratum exhibited a high P removal (89.9%). The mean P efluent concentration and P removal rate were 1.34 ± 0.95 mg/L and 0.32 ± 0.03 g/m2/d, respectively. The mass balance study showed that media sorption was the dominant P removal pathway (77.5%), followed by microbial assimilation (14.5%), plant uptake (5.4%), and other processes (2.6%). It was estimated the WHC-based bed could work effectively for approximately 2.84 years. This WHC-based HSSF-CWs technology will therefore pave the way for recycling Ca-rich waste materials as media in HSSF-CWs to enhance P-rich wastewater purification.
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Affiliation(s)
- T A H Nguyen
- Vietnam Japan University (VNU-VJU), Vietnam National University, Hanoi, Luu Huu Phuoc St., Nam Tu Liem Dist., Hanoi 101000, Viet Nam
| | - H H Ngo
- Centre for Technology in Water and Wastewater, School of Civil and Environmental Engineering, University of Technology, Sydney (UTS), 15 Broadway, Ultimo, NSW 2007, Australia.
| | - W S Guo
- Centre for Technology in Water and Wastewater, School of Civil and Environmental Engineering, University of Technology, Sydney (UTS), 15 Broadway, Ultimo, NSW 2007, Australia
| | - T H H Nguyen
- University of Science (VNU-HUS), Vietnam National University, Hanoi, 334 Nguyen Trai Rd., Thanh Xuan Dist., Hanoi 120106, Viet Nam
| | - S Soda
- Graduate School of Science and Engineering, Ritsumeikan University (RITs), Biwako-Kusatsu Campus, Shiga 525-8577, Japan
| | - N D Vu
- University of Science (VNU-HUS), Vietnam National University, Hanoi, 334 Nguyen Trai Rd., Thanh Xuan Dist., Hanoi 120106, Viet Nam
| | - T K A Bui
- Institute of Environmental Technology (IET), Vietnam Academy of Science and Technology (VAST), 18 Hoang Quoc Viet Rd., Cau Giay Dist., Hanoi 100000, Viet Nam
| | - T D H Vo
- Faculty of Environmental and Food Engineering, Nguyen Tat Thanh University (NTTU), 300A Nguyen Tat Thanh St., Ward 13, Dist. 4, Ho Chi Minh City 700000, Viet Nam
| | - X T Bui
- Faculty of Environment and Natural Resources, Ho Chi Minh City University of Technology (HCMUT), 268 Ly Thuong Kiet St., Dist.10, Ho Chi Minh City 700910, Viet Nam
| | - T T Nguyen
- Graduate School of Science and Engineering, Ritsumeikan University (RITs), Biwako-Kusatsu Campus, Shiga 525-8577, Japan
| | - T T Pham
- Vietnam Japan University (VNU-VJU), Vietnam National University, Hanoi, Luu Huu Phuoc St., Nam Tu Liem Dist., Hanoi 101000, Viet Nam
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Trinh VT, Nguyen TMP, Van HT, Hoang LP, Nguyen TV, Ha LT, Vu XH, Pham TT, Nguyen TN, Quang NV, Nguyen XC. Phosphate Adsorption by Silver Nanoparticles-Loaded Activated Carbon derived from Tea Residue. Sci Rep 2020; 10:3634. [PMID: 32107469 PMCID: PMC7046672 DOI: 10.1038/s41598-020-60542-0] [Citation(s) in RCA: 49] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2019] [Accepted: 02/11/2020] [Indexed: 11/24/2022] Open
Abstract
This study presents the removal of phosphate from aqueous solution using a new silver nanoparticles-loaded tea activated carbon (AgNPs-TAC) material. In order to reduce costs, the tea activated carbon was produced from tea residue. Batch adsorption experiments were conducted to evaluate the effects of impregnation ratio of AgNPs and TAC, pH solution, contact time, initial phosphate concentration and dose of AgNPs-AC on removing phosphate from aqueous solution. Results show that the best conditions for phosphate adsorption occurred at the impregnation ratio AgNPs/TAC of 3% w/w, pH 3, and contact time lasting 150 min. The maximum adsorption capacity of phosphate on AgNPs-TAC determined by the Langmuir model was 13.62 mg/g at an initial phosphate concentration of 30 mg/L. The adsorption isotherm of phosphate on AgNPs-TAC fits well with both the Langmuir and Sips models. The adsorption kinetics data were also described well by the pseudo-first-order and pseudo-second-order models with high correlation coefficients of 0.978 and 0.966, respectively. The adsorption process was controlled by chemisorption through complexes and ligand exchange mechanisms. This study suggests that AgNPs-TAC is a promising, low cost adsorbent for phosphate removal from aqueous solution.
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Affiliation(s)
- Van Tuyen Trinh
- Institute of Environmental Technology, Vietnam Academy of Science and Technology, 18 Hoang Quoc Viet road, Ha Noi city, Vietnam
| | - Thi Minh Phuong Nguyen
- Faculty of Environment and Chemical Engineering, Duy Tan University (DTU), 254 Nguyen Van Linh road, Da Nang, Vietnam
| | - Huu Tap Van
- Faculty of Natural Resources and Environment, TNU-University of Sciences (TNUS), Tan Thinh Ward, Thai Nguyen City, Vietnam
| | - Le Phuong Hoang
- Faculty of Civil and Environmental Engineering, Thai Nguyen University of Technology (TNUT), Tich Luong Ward, Thai Nguyen City, Vietnam
| | - Tien Vinh Nguyen
- Faculty of Engineering and IT, University of Technology Sydney (UTS), Box 123, Broadway, Sydney, PO, Australia
| | - L T Ha
- Faculty of Physics and Technology, TNU-University of Sciences (TNUS), Tan Thinh Ward, Thai Nguyen City, Vietnam
| | - Xuan Hoa Vu
- Faculty of Physics and Technology, TNU-University of Sciences (TNUS), Tan Thinh Ward, Thai Nguyen City, Vietnam
| | - T T Pham
- Institute of Research and Development, Duy Tan University, Da Nang, 550000, Vietnam
| | - Thi Nu Nguyen
- Cao Bang Teacher's Training College, De Tham road, Cao Bang town, Cao Bang Province, Vietnam
| | - N V Quang
- Faculty of Chemistry, Ha Noi Pedagogical University 2, Vinh Phuc, Vietnam
| | - X C Nguyen
- Laboratory of Advanced Materials Chemistry, Advanced Institute of Materials Science, Ton Duc Thang University, Ho Chi Minh City, Vietnam.
- Faculty of Applied Sciences, Ton Duc Thang University, Ho Chi Minh City, Vietnam.
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10
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Pham TT, Punsawad C, Glaharn S, De Meyer SF, Viriyavejakul P, Van den Steen PE. Release of endothelial activation markers in lungs of patients with malaria-associated acute respiratory distress syndrome. Malar J 2019; 18:395. [PMID: 31796023 PMCID: PMC6891978 DOI: 10.1186/s12936-019-3040-3] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [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: 09/25/2019] [Accepted: 11/26/2019] [Indexed: 11/17/2022] Open
Abstract
Background Malaria-associated acute respiratory distress syndrome (MA-ARDS) is an understudied complication of malaria and is characterized by pulmonary inflammation and disruption of the alveolar-capillary membrane. Its pathogenesis remains poorly understood. Since endothelial activation plays an important role in other malarial complications, the expression of two endothelial activation markers, von Willebrand factor (VWF) and angiopoietin-2 (ANG-2), was investigated in the lungs of patients with MA-ARDS. Methods Post-mortem lung sections of Plasmodium falciparum-infected patients without alveolar oedema (NA), P. falciparum-infected patients with alveolar oedema (MA-ARDS), and uninfected people who died accidentally with no pathological changes to the lungs (CON) were immunohistochemically stained for VWF and ANG-2, and were evaluated with semi-quantitative analysis. Results Alveolar oedematous VWF and ANG-2 and intravascular VWF staining were significantly increased in patients with MA-ARDS versus infected and uninfected control groups. The levels of VWF in the alveolar septa and endothelial lining of large blood vessels of patients with MA-ARDS was significantly decreased compared to controls. ANG-2 expression was increased in the alveolar septa of malaria patients without alveolar oedema versus control patients, while ANG-2+ leukocytes were increased in the alveoli in both infected patient groups. Conclusions This study documents a high level of VWF and ANG-2, two endothelial activation markers in the oedematous alveoli of post-mortem lung sections of Thai patients with MA-ARDS. Decreased detection of VWF in the endothelial lining of blood vessels, in parallel with an increased presence of intravascular VWF staining suggests marked endothelial activation and Weibel–Palade body release in the lungs of patients with MA-ARDS.
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Affiliation(s)
- Thao-Thy Pham
- Laboratory of Immunoparasitology, Department of Microbiology and Immunology, Rega Institute for Medical Research, KU Leuven, University of Leuven, Leuven, Belgium
| | - Chuchard Punsawad
- School of Medicine, Walailak University, Nakhon Si Thammarat, Thailand
| | - Supattra Glaharn
- Department of Tropical Pathology, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand
| | - Simon F De Meyer
- Laboratory for Thrombosis Research, KU Leuven Campus Kulak Kortrijk, Kortrijk, Belgium
| | - Parnpen Viriyavejakul
- Department of Tropical Pathology, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand
| | - Philippe E Van den Steen
- Laboratory of Immunoparasitology, Department of Microbiology and Immunology, Rega Institute for Medical Research, KU Leuven, University of Leuven, Leuven, Belgium.
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11
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Kraisin S, Verhenne S, Pham TT, Martinod K, Tersteeg C, Vandeputte N, Deckmyn H, Vanhoorelbeke K, Van den Steen PE, De Meyer SF. von Willebrand factor in experimental malaria-associated acute respiratory distress syndrome. J Thromb Haemost 2019; 17:1372-1383. [PMID: 31099973 PMCID: PMC9906160 DOI: 10.1111/jth.14485] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2019] [Accepted: 05/02/2019] [Indexed: 12/22/2022]
Abstract
BACKGROUND Malaria-associated acute respiratory distress syndrome (MA-ARDS) is a lethal complication of severe malaria, characterized by marked pulmonary inflammation. Patient studies have suggested a link between von Willebrand factor (VWF) and malaria severity. OBJECTIVES To investigate the role of VWF in the pathogenesis of experimental MA-ARDS. METHODS Plasmodium berghei NK65-E (PbNK65) parasites were injected in Vwf+/+ and Vwf-/- mice. Pathological parameters were assessed following infection. RESULTS In accordance with patients with severe malaria, plasma VWF levels were increased and ADAMTS13 activity levels were reduced in experimental MA-ARDS. ADAMTS13- and plasmin-independent reductions of high molecular weight VWF multimers were observed at the end stage of disease. Thrombocytopenia was VWF-independent because it was observed in both Vwf+/+ and Vwf-/- mice. Interestingly, Vwf-/- mice had a shorter survival time compared with Vwf+/+ controls following PbNK65 infection. Lung edema could not explain this shortened survival because alveolar protein levels in Vwf-/- mice were approximately two times lower than in Vwf+/+ controls. Parasite load, on the other hand, was significantly increased in Vwf-/- mice compared with Vwf+/+ mice in both peripheral blood and lung tissue. In addition, anemia was only observed in PbNK65-infected Vwf-/- mice. Of note, Vwf-/- mice presented with two times more reticulocytes, a preferential target of the parasites. CONCLUSIONS This study suggests that parasite load together with malarial anemia, rather than alveolar leakage, might contribute to shortened survival in PbNK65-infected Vwf-/- mice. VWF deficiency is associated with early reticulocytosis following PbNK65 infection, which potentially explains the increase in parasite load.
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Affiliation(s)
- Sirima Kraisin
- Laboratory for Thrombosis Research, KU Leuven Campus Kulak Kortrijk, Kortrijk, Belgium
| | - Sebastien Verhenne
- Laboratory for Thrombosis Research, KU Leuven Campus Kulak Kortrijk, Kortrijk, Belgium
| | - Thao-Thy Pham
- Laboratory of Immunoparasitology, Rega Institute for Medical Research, KU Leuven, Leuven, Belgium
| | - Kimberly Martinod
- Laboratory for Thrombosis Research, KU Leuven Campus Kulak Kortrijk, Kortrijk, Belgium
| | - Claudia Tersteeg
- Laboratory for Thrombosis Research, KU Leuven Campus Kulak Kortrijk, Kortrijk, Belgium
| | - Nele Vandeputte
- Laboratory for Thrombosis Research, KU Leuven Campus Kulak Kortrijk, Kortrijk, Belgium
| | - Hans Deckmyn
- Laboratory for Thrombosis Research, KU Leuven Campus Kulak Kortrijk, Kortrijk, Belgium
| | - Karen Vanhoorelbeke
- Laboratory for Thrombosis Research, KU Leuven Campus Kulak Kortrijk, Kortrijk, Belgium
| | - Philippe E Van den Steen
- Laboratory of Immunoparasitology, Rega Institute for Medical Research, KU Leuven, Leuven, Belgium
| | - Simon F De Meyer
- Laboratory for Thrombosis Research, KU Leuven Campus Kulak Kortrijk, Kortrijk, Belgium
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12
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Vandermosten L, Pham TT, Knoops S, De Geest C, Lays N, Van der Molen K, Kenyon CJ, Verma M, Chapman KE, Schuit F, De Bosscher K, Opdenakker G, Van den Steen PE. Adrenal hormones mediate disease tolerance in malaria. Nat Commun 2018; 9:4525. [PMID: 30375380 PMCID: PMC6207723 DOI: 10.1038/s41467-018-06986-5] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2017] [Accepted: 10/05/2018] [Indexed: 12/17/2022] Open
Abstract
Malaria reduces host fitness and survival by pathogen-mediated damage and inflammation. Disease tolerance mechanisms counter these negative effects without decreasing pathogen load. Here, we demonstrate that in four different mouse models of malaria, adrenal hormones confer disease tolerance and protect against early death, independently of parasitemia. Surprisingly, adrenalectomy differentially affects malaria-induced inflammation by increasing circulating cytokines and inflammation in the brain but not in the liver or lung. Furthermore, without affecting the transcription of hepatic gluconeogenic enzymes, adrenalectomy causes exhaustion of hepatic glycogen and insulin-independent lethal hypoglycemia upon infection. This hypoglycemia is not prevented by glucose administration or TNF-α neutralization. In contrast, treatment with a synthetic glucocorticoid (dexamethasone) prevents the hypoglycemia, lowers cerebral cytokine expression and increases survival rates. Overall, we conclude that in malaria, adrenal hormones do not protect against lung and liver inflammation. Instead, they prevent excessive systemic and brain inflammation and severe hypoglycemia, thereby contributing to tolerance. Disease tolerance mechanisms counter the negative effects of infection without decreasing the pathogen load. Here, the authors show that in mouse models of malaria, such disease tolerance can be conferred by adrenal hormones, by preventing excessive inflammation and hypoglycemia.
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Affiliation(s)
- Leen Vandermosten
- Laboratory of Immunobiology, Department of Microbiology and Immunology, Rega Institute for Medical Research, KU Leuven, Leuven, 3000, Belgium
| | - Thao-Thy Pham
- Laboratory of Immunobiology, Department of Microbiology and Immunology, Rega Institute for Medical Research, KU Leuven, Leuven, 3000, Belgium
| | - Sofie Knoops
- Laboratory of Immunobiology, Department of Microbiology and Immunology, Rega Institute for Medical Research, KU Leuven, Leuven, 3000, Belgium
| | - Charlotte De Geest
- Laboratory of Immunobiology, Department of Microbiology and Immunology, Rega Institute for Medical Research, KU Leuven, Leuven, 3000, Belgium
| | - Natacha Lays
- Laboratory of Immunobiology, Department of Microbiology and Immunology, Rega Institute for Medical Research, KU Leuven, Leuven, 3000, Belgium
| | - Kristof Van der Molen
- Laboratory of Immunobiology, Department of Microbiology and Immunology, Rega Institute for Medical Research, KU Leuven, Leuven, 3000, Belgium
| | - Christopher J Kenyon
- Centre for Cardiovascular Science, The Queen's Medical Research Institute, University of Edinburgh, Edinburgh, EH16 4TJ, United Kingdom
| | - Manu Verma
- Centre for Cardiovascular Science, The Queen's Medical Research Institute, University of Edinburgh, Edinburgh, EH16 4TJ, United Kingdom
| | - Karen E Chapman
- Centre for Cardiovascular Science, The Queen's Medical Research Institute, University of Edinburgh, Edinburgh, EH16 4TJ, United Kingdom
| | - Frans Schuit
- Gene Expression Unit, Department of Cellular and Molecular Medicine, KU Leuven, Leuven, 3000, Belgium
| | - Karolien De Bosscher
- Nuclear Receptor Lab, Receptor Research Laboratories, VIB Center for Medical Biotechnology, Ghent University, Gent, 9000, Belgium
| | - Ghislain Opdenakker
- Laboratory of Immunobiology, Department of Microbiology and Immunology, Rega Institute for Medical Research, KU Leuven, Leuven, 3000, Belgium
| | - Philippe E Van den Steen
- Laboratory of Immunobiology, Department of Microbiology and Immunology, Rega Institute for Medical Research, KU Leuven, Leuven, 3000, Belgium.
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13
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Vandermosten L, Pham TT, Possemiers H, Knoops S, Van Herck E, Deckers J, Franke-Fayard B, Lamb TJ, Janse CJ, Opdenakker G, Van den Steen PE. Experimental malaria-associated acute respiratory distress syndrome is dependent on the parasite-host combination and coincides with normocyte invasion. Malar J 2018; 17:102. [PMID: 29506544 PMCID: PMC5839036 DOI: 10.1186/s12936-018-2251-3] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [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: 11/28/2017] [Accepted: 02/27/2018] [Indexed: 12/13/2022] Open
Abstract
Background Malaria-associated acute respiratory distress syndrome (MA-ARDS) is a complication of malaria with a lethality rate of up to 80% despite anti-malarial treatment. It is characterized by a vast infiltration of leukocytes, microhaemorrhages and vasogenic oedema in the lungs. Previously, a mouse model for MA-ARDS was developed by infection of C57BL/6 mice with the Edinburgh line NK65-E of Plasmodium berghei. Results Here, both host and parasite factors were demonstrated to play crucial roles in the development and severity of lung pathology. In particular, the genetic constitution of the host was an important determinant in the development of MA-ARDS. Both male and female C57BL/6, but not BALB/c, mice developed MA-ARDS when infected with P. berghei NK65-E. However, the New York line of P. berghei NK65 (NK65-NY) did not induce demonstrable MA-ARDS, despite its accumulation in the lungs and fat tissue to a similar or even higher extent as P. berghei NK65-E. These two commonly used lines of P. berghei differ in their red blood cell preference. P. berghei NK65-NY showed a stronger predilection for reticulocytes than P. berghei NK65-E and this appeared to be associated with a lower pathogenicity in the lungs. The pulmonary pathology in the C57BL/6/P. berghei NK65-E model was more pronounced than in the model with infection of DBA/2 mice with P. berghei strain ANKA. The transient lung pathology in DBA/2 mice infected with P. berghei ANKA coincided with the infection phase in which parasites mainly infected normocytes. This phase was followed by a less pathogenic phase in which P. berghei ANKA mainly infected reticulocytes. Conclusions The propensity of mice to develop MA-ARDS during P. berghei infection depends on both host and parasite factors and appears to correlate with RBC preference. These data provide insights in induction of MA-ARDS and may guide the choice of different mouse-parasite combinations to study lung pathology.
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Affiliation(s)
- Leen Vandermosten
- Laboratory of Immunobiology, Department of Microbiology and Immunology, Rega Institute for Medical Research, KU Leuven-University of Leuven, Herestraat 49, box 1044, 3000, Leuven, Belgium
| | - Thao-Thy Pham
- Laboratory of Immunobiology, Department of Microbiology and Immunology, Rega Institute for Medical Research, KU Leuven-University of Leuven, Herestraat 49, box 1044, 3000, Leuven, Belgium
| | - Hendrik Possemiers
- Laboratory of Immunobiology, Department of Microbiology and Immunology, Rega Institute for Medical Research, KU Leuven-University of Leuven, Herestraat 49, box 1044, 3000, Leuven, Belgium
| | - Sofie Knoops
- Laboratory of Immunobiology, Department of Microbiology and Immunology, Rega Institute for Medical Research, KU Leuven-University of Leuven, Herestraat 49, box 1044, 3000, Leuven, Belgium
| | - Evelien Van Herck
- Laboratory of Immunobiology, Department of Microbiology and Immunology, Rega Institute for Medical Research, KU Leuven-University of Leuven, Herestraat 49, box 1044, 3000, Leuven, Belgium
| | - Julie Deckers
- Laboratory of Immunobiology, Department of Microbiology and Immunology, Rega Institute for Medical Research, KU Leuven-University of Leuven, Herestraat 49, box 1044, 3000, Leuven, Belgium.,Laboratory of Immunoregulation, VIB Center for Inflammation Research, Department of Internal Medicine, Ghent University, Technologiepark 927, 9052, Ghent, Belgium
| | - Blandine Franke-Fayard
- Leiden Malaria Research Group, Department of Parasitology, Leiden University Medical Center (LUMC), Albinusdreef 2, 2333 ZA, Leiden, The Netherlands
| | - Tracey J Lamb
- Department of Pathology, University of Utah, 15 N Medical Drive E, Salt Lake City, UT, 84112, USA
| | - Chris J Janse
- Leiden Malaria Research Group, Department of Parasitology, Leiden University Medical Center (LUMC), Albinusdreef 2, 2333 ZA, Leiden, The Netherlands
| | - Ghislain Opdenakker
- Laboratory of Immunobiology, Department of Microbiology and Immunology, Rega Institute for Medical Research, KU Leuven-University of Leuven, Herestraat 49, box 1044, 3000, Leuven, Belgium
| | - Philippe E Van den Steen
- Laboratory of Immunobiology, Department of Microbiology and Immunology, Rega Institute for Medical Research, KU Leuven-University of Leuven, Herestraat 49, box 1044, 3000, Leuven, Belgium.
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14
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Pham TT, Verheijen M, Vandermosten L, Deroost K, Knoops S, Van den Eynde K, Boon L, Janse CJ, Opdenakker G, Van den Steen PE. Pathogenic CD8 + T Cells Cause Increased Levels of VEGF-A in Experimental Malaria-Associated Acute Respiratory Distress Syndrome, but Therapeutic VEGFR Inhibition Is Not Effective. Front Cell Infect Microbiol 2017; 7:416. [PMID: 29034214 PMCID: PMC5627041 DOI: 10.3389/fcimb.2017.00416] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [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: 05/24/2017] [Accepted: 09/06/2017] [Indexed: 12/29/2022] Open
Abstract
Malaria is a severe disease and kills over 400,000 people each year. Malarial complications are the main cause of death and include cerebral malaria and malaria-associated acute respiratory distress syndrome (MA-ARDS). Despite antimalarial treatment, lethality rates of MA-ARDS are still between 20 and 80%. Patients develop pulmonary edema with hemorrhages and leukocyte extravasation in the lungs. The vascular endothelial growth factor-A (VEGF-A) and the placental growth factor (PlGF) are vascular permeability factors and may be involved in the disruption of the alveolar-capillary membrane, leading to alveolar edema. We demonstrated increased pulmonary VEGF-A and PlGF levels in lungs of mice with experimental MA-ARDS. Depletion of pathogenic CD8+ T cells blocked pulmonary edema and abolished the increase of VEGF-A and PlGF. However, neutralization of VEGF receptor-2 (VEGFR-2) with the monoclonal antibody clone DC101 did not decrease pulmonary pathology. The broader spectrum receptor tyrosine kinase inhibitor sunitinib even increased lung pathology. These data suggest that the increase in alveolar VEGF-A and PlGF is not a cause but rather a consequence of the pulmonary pathology in experimental MA-ARDS and that therapeutic inhibition of VEGF receptors is not effective and even contra-indicated.
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Affiliation(s)
- Thao-Thy Pham
- Laboratory of Immunobiology, Department of Microbiology and Immunology, Rega Institute for Medical Research, KU Leuven-University of LeuvenLeuven, Belgium
| | - Melissa Verheijen
- Laboratory of Immunobiology, Department of Microbiology and Immunology, Rega Institute for Medical Research, KU Leuven-University of LeuvenLeuven, Belgium
| | - Leen Vandermosten
- Laboratory of Immunobiology, Department of Microbiology and Immunology, Rega Institute for Medical Research, KU Leuven-University of LeuvenLeuven, Belgium
| | - Katrien Deroost
- Laboratory of Immunobiology, Department of Microbiology and Immunology, Rega Institute for Medical Research, KU Leuven-University of LeuvenLeuven, Belgium
| | - Sofie Knoops
- Laboratory of Immunobiology, Department of Microbiology and Immunology, Rega Institute for Medical Research, KU Leuven-University of LeuvenLeuven, Belgium
| | | | | | - Chris J Janse
- Leiden Malaria Research Group, Department of Parasitology, Leiden University Medical CenterLeiden, Netherlands
| | - Ghislain Opdenakker
- Laboratory of Immunobiology, Department of Microbiology and Immunology, Rega Institute for Medical Research, KU Leuven-University of LeuvenLeuven, Belgium
| | - Philippe E Van den Steen
- Laboratory of Immunobiology, Department of Microbiology and Immunology, Rega Institute for Medical Research, KU Leuven-University of LeuvenLeuven, Belgium
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15
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Do TC, Boettiger D, Law M, Pujari S, Zhang F, Chaiwarith R, Kiertiburanakul S, Lee MP, Ditangco R, Wong WW, Nguyen KV, Merati TP, Pham TT, Kamarulzaman A, Oka S, Yunihastuti E, Kumarasamy N, Kantipong P, Choi JY, Ng OT, Durier N, Ruxrungtham K. Smoking and projected cardiovascular risk in an HIV-positive Asian regional cohort. HIV Med 2017; 17:542-9. [PMID: 27430354 DOI: 10.1111/hiv.12358] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/30/2015] [Indexed: 11/28/2022]
Abstract
OBJECTIVES The aim of the study was to assess the prevalence and characteristics associated with current smoking in an Asian HIV-positive cohort, to calculate the predictive risks of cardiovascular disease (CVD), coronary heart disease (CHD) and myocardial infarction (MI), and to identify the impact that simulated interventions may have. METHODS Logistic regression analysis was used to distinguish associated current smoking characteristics. Five-year predictive risks of CVD, CHD and MI and the impact of simulated interventions were calculated utilizing the Data Collection on Adverse Effects of Anti-HIV Drugs Study (D:A:D) algorithm. RESULTS Smoking status data were collected from 4274 participants and 1496 of these had sufficient data for simulated intervention calculations. Current smoking prevalence in these two groups was similar (23.2% vs. 19.9%, respectively). Characteristics associated with current smoking included age > 50 years compared with 30-39 years [odds ratio (OR) 0.65; 95% confidence interval (CI) 0.51-0.83], HIV exposure through injecting drug use compared with heterosexual exposure (OR 3.03; 95% CI 2.25-4.07), and receiving antiretroviral therapy (ART) at study sites in Singapore, South Korea, Malaysia, Japan and Vietnam in comparison to Thailand (all OR > 2). Women were less likely to smoke than men (OR 0.11; 95% CI 0.08-0.14). In simulated interventions, smoking cessation demonstrated the greatest impact in reducing CVD and CHD risk and closely approximated the impact of switching from abacavir to an alternate antiretroviral in the reduction of 5-year MI risk. CONCLUSIONS Multiple interventions could reduce CVD, CHD and MI risk in Asian HIV-positive patients, with smoking cessation potentially being the most influential.
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Affiliation(s)
- T C Do
- HIVNAT/Thai Red Cross AIDS Research Center, Bangkok, Thailand
| | - D Boettiger
- The Kirby Institute, UNSW Australia, Sydney, Australia
| | - M Law
- The Kirby Institute, UNSW Australia, Sydney, Australia
| | - S Pujari
- Institute of Infectious Diseases, Pune, India
| | - F Zhang
- Beijing Ditan Hospital, Capital Medical University, Beijing, China
| | - R Chaiwarith
- Research Institute for Health Sciences, Chiang Mai, Thailand
| | - S Kiertiburanakul
- Faculty of Medicine, Ramathibodi Hospital, Mahidol University, Bangkok, Thailand
| | - M P Lee
- Queen Elizabeth Hospital, Hong Kong, China
| | - R Ditangco
- Research Institute for Tropical Medicine, Manila, Philippines
| | - W W Wong
- Taipei Veterans General Hospital, Taipei, Taiwan
| | - K V Nguyen
- National Hospital for Tropical Diseases, Hanoi, Vietnam
| | - T P Merati
- Faculty of Medicine Udayana University & Sanglah Hospital, Bali, Indonesia
| | - T T Pham
- Bach Mai Hospital, Hanoi, Vietnam
| | - A Kamarulzaman
- University Malaya Medical Center, Kuala Lumpur, Malaysia
| | - S Oka
- AIDS Clinical Center, National Center for Global Health and Medicine, Tokyo, Japan
| | - E Yunihastuti
- Working Group on AIDS Faculty of Medicine, University of Indonesia/Cipto Mangunkusumo Hospital, Jakarta, Indonesia
| | - N Kumarasamy
- Chennai Antiviral Research and Treatment Clinical Research Site (CART CRS), YRGCARE Medical Centre, VHS, Chennai, India
| | - P Kantipong
- Chiangrai Prachanukroh Hospital, Chiang Rai, Thailand
| | - J Y Choi
- Department of Internal Medicine and AIDS Research Institute, Yonsei University College of Medicine, Seoul, South Korea
| | - O T Ng
- Tan Tock Seng Hospital, Singapore
| | - N Durier
- TREAT Asia, amfAR - The Foundation for AIDS Research, Bangkok, Thailand
| | - K Ruxrungtham
- HIVNAT/Thai Red Cross AIDS Research Center, Bangkok, Thailand.,Department of Medicine, Faculty of Medicine, Chulalongkorn University, Bangkok, Thailand
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16
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Pham TT, Bayle Iniguez X, Mansat P, Maubisson L, Bonnevialle N. Postoperative pain after arthroscopic versus open rotator cuff repair. A prospective study. Orthop Traumatol Surg Res 2016; 102:13-7. [PMID: 26797002 DOI: 10.1016/j.otsr.2015.11.005] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/07/2015] [Revised: 08/31/2015] [Accepted: 11/02/2015] [Indexed: 02/02/2023]
Abstract
INTRODUCTION Although the arthroscopic technique is becoming the gold standard for rotator cuff tendon repair, there is no proof that this technique results in less postoperative pain compared to open repair. The aim of this study was to prospectively compare the postoperative pain level after arthroscopic or open rotator cuff repair and to define factors that could influence its course. MATERIALS AND METHODS Between January 2012 and January 2013, 95 patients were operated for a rotator cuff tear: 45 using an arthroscopic technique and 50 an open technique. Daily analgesic use and self-evaluation of pain level using a visual analogic scale were recorded preoperatively and twice a day postoperatively during the first 6 weeks. These data were compared between the two groups and analyzed according to patients' demographic data and preoperative evaluation of the tear. RESULTS The preoperative pain level was equivalent in the two groups (P=0.22). Postoperatively, level-2 analgesic medication use was greater in the arthroscopic group after the 4th week (P=0.01). A pain-free shoulder was obtained before the 6th week in 75% and 66% of the patients after arthroscopic or open repair, respectively (P=0.34). There was a positive correlation between the preoperative and postoperative pain level (r=0.25; P=0.02). Work compensation patients experienced more pain postoperatively (P=0.08). Level-III analgesic medication use was greater for patients with massive rotator cuff tear (P=0.001). CONCLUSION No evidence was found on the superiority of arthroscopy versus open repair of rotator cuff tear concerning the postoperative pain level. The choice of the surgical technique should not be based on this argument. LEVEL OF EVIDENCE II.
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Affiliation(s)
- T T Pham
- Institut de l'appareil locomoteur, hôpital Pierre-Paul-Riquet, place du Docteur-Baylac, 31059 Toulouse, France.
| | - X Bayle Iniguez
- Institut de l'appareil locomoteur, hôpital Pierre-Paul-Riquet, place du Docteur-Baylac, 31059 Toulouse, France
| | - P Mansat
- Institut de l'appareil locomoteur, hôpital Pierre-Paul-Riquet, place du Docteur-Baylac, 31059 Toulouse, France
| | - L Maubisson
- EA CNRS 6296, IAE de Tours, université François-Rabelais, 37200 Tours, France
| | - N Bonnevialle
- Institut de l'appareil locomoteur, hôpital Pierre-Paul-Riquet, place du Docteur-Baylac, 31059 Toulouse, France
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Deroost K, Pham TT, Opdenakker G, Van den Steen PE. The immunological balance between host and parasite in malaria. FEMS Microbiol Rev 2015; 40:208-57. [PMID: 26657789 DOI: 10.1093/femsre/fuv046] [Citation(s) in RCA: 76] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/04/2015] [Indexed: 12/16/2022] Open
Abstract
Coevolution of humans and malaria parasites has generated an intricate balance between the immune system of the host and virulence factors of the parasite, equilibrating maximal parasite transmission with limited host damage. Focusing on the blood stage of the disease, we discuss how the balance between anti-parasite immunity versus immunomodulatory and evasion mechanisms of the parasite may result in parasite clearance or chronic infection without major symptoms, whereas imbalances characterized by excessive parasite growth, exaggerated immune reactions or a combination of both cause severe pathology and death, which is detrimental for both parasite and host. A thorough understanding of the immunological balance of malaria and its relation to other physiological balances in the body is of crucial importance for developing effective interventions to reduce malaria-related morbidity and to diminish fatal outcomes due to severe complications. Therefore, we discuss in this review the detailed mechanisms of anti-malarial immunity, parasite virulence factors including immune evasion mechanisms and pathogenesis. Furthermore, we propose a comprehensive classification of malaria complications according to the different types of imbalances.
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Affiliation(s)
- Katrien Deroost
- Laboratory of Immunobiology, Rega Institute for Medical Research, KU Leuven - University of Leuven, 3000 Leuven, Belgium The Francis Crick Institute, Mill Hill Laboratory, London, NW71AA, UK
| | - Thao-Thy Pham
- Laboratory of Immunobiology, Rega Institute for Medical Research, KU Leuven - University of Leuven, 3000 Leuven, Belgium
| | - Ghislain Opdenakker
- Laboratory of Immunobiology, Rega Institute for Medical Research, KU Leuven - University of Leuven, 3000 Leuven, Belgium
| | - Philippe E Van den Steen
- Laboratory of Immunobiology, Rega Institute for Medical Research, KU Leuven - University of Leuven, 3000 Leuven, Belgium
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Pham TT, Lenoir H, Coulet B, Wargny M, Lazerges C, Chammas M. Proximal row carpectomy in total arthrodesis of the rheumatoid wrist. Orthop Traumatol Surg Res 2015; 101:919-22. [PMID: 26611715 DOI: 10.1016/j.otsr.2015.09.032] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/07/2015] [Revised: 07/09/2015] [Accepted: 09/10/2015] [Indexed: 02/02/2023]
Abstract
BACKGROUND Advanced proximal carpal row damage is common in rheumatoid arthritis (RA). Proximal row carpectomy (PRC) simplifies total wrist arthrodesis, obviating the need for an iliac bone graft. In theory, PRC also improves the chances of healing, as fusion of a single joint space is needed for the procedure to be successful. Potential effects of the loss of carpal height related to PRC are unknown. HYPOTHESIS We hypothesised that PRC performed concomitantly with total wrist arthrodesis in patients with RA produces good clinical and radiological outcomes, without inducing loss of strength or digital deformities. MATERIAL AND METHODS In 38 total arthrodeses of rheumatoid wrists, a clinical evaluation was performed, including a visual analogue scale (VAS) pain score, the Patient-Rated Wrist Evaluation (PRWE), grip strength, digital deformities, and patient satisfaction. A standard radiographic workup was obtained to assess healing and carpal height indices. RESULTS After a mean follow-up of 50 months, the mean VAS pain score was 0.4 (range: 0-7), the mean PRWE score was 21 (range: 0-80.5), and grip strength as a percentage of the contralateral limb was 76%. The healing rate was 92% (35/38 wrists), and 34 (90%) patients reported being satisfied or very satisfied. No effects of carpal height loss on clinical or radiographic parameters was detected. DISCUSSION Total wrist arthrodesis combined with PRC provides reliable and reproducible benefits. This study found no evidence of adverse effects related to the loss of carpal height. LEVEL OF EVIDENCE IV, retrospective study.
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Affiliation(s)
- T T Pham
- Service de chirurgie orthopédique et traumatologique, hôpital Pierre-Paul-Riquet, CHRU de Toulouse, rue Jean-Dausset, 31000 Toulouse, France
| | - H Lenoir
- Service de chirurgie orthopédique et traumatologique, hôpital Pierre-Paul-Riquet, CHRU de Toulouse, rue Jean-Dausset, 31000 Toulouse, France.
| | - B Coulet
- Service de chirurgie de la main et du membre supérieur, hôpital Lapeyronie, CHRU de Montpellier, 34295 Montpellier, France
| | - M Wargny
- Laboratoire d'épidémiologie, CHRU de Toulouse, 31073 Toulouse, France
| | - C Lazerges
- Service de chirurgie de la main et du membre supérieur, hôpital Lapeyronie, CHRU de Montpellier, 34295 Montpellier, France
| | - M Chammas
- Service de chirurgie de la main et du membre supérieur, hôpital Lapeyronie, CHRU de Montpellier, 34295 Montpellier, France
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Lemaire T, Pham TT, Capiez-Lernout E, de Leeuw NH, Naili S. Water in hydroxyapatite nanopores: Possible implications for interstitial bone fluid flow. J Biomech 2015; 48:3066-71. [PMID: 26283410 DOI: 10.1016/j.jbiomech.2015.07.025] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2015] [Revised: 07/20/2015] [Accepted: 07/23/2015] [Indexed: 11/19/2022]
Abstract
The role of bone water in the activity of this organ is essential in structuring apatite crystals, providing pathways for nutrients and waste involved in the metabolism of bone cells and participating in bone remodelling mechanotransduction. It is commonly accepted that bone presents three levels of porosity, namely the vasculature, the lacuno-canalicular system and the voids of the collagen-apatite matrix. Due to the observation of bound state of water at the latter level, the interstitial nanoscopic flow that may exist within these pores is classically neglected. The aim of this paper is to investigate the possibility to obtain a fluid flow at the nanoscale. That is why a molecular dynamics based analysis of a water-hydroxyapatite system is proposed to analyze the effect of water confinement on transport properties. The main result here is that free water can be observed inside hydroxyapatite pores of a few nanometers. This result would have strong implications in the multiscale treatment of the poromechanical behaviour of bone tissue. In particular, the mechanical properties of the bone matrix may be highly controlled by nanoscopic water diffusion and the classical idea that osteocytic activity is only regulated by bone fluid flow within the lacuno-canalicular system may be discussed again.
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Affiliation(s)
- T Lemaire
- Université Paris-Est, Laboratoire Modélisation et Simulation Multi Echelle, MSME UMR 8208 CNRS, France; 94010 Créteil cedex, France.
| | - T T Pham
- Université Paris-Est, Laboratoire Modélisation et Simulation Multi Echelle, MSME UMR 8208 CNRS, France; 94010 Créteil cedex, France
| | - E Capiez-Lernout
- Université Paris-Est, Laboratoire Modélisation et Simulation Multi Echelle, MSME UMR 8208 CNRS, France; 77454 Marne la Vallée cedex 2, France
| | - N H de Leeuw
- Department of Chemistry, University College London, 20 Gordon Street, London WC1H 0AJ, UK
| | - S Naili
- Université Paris-Est, Laboratoire Modélisation et Simulation Multi Echelle, MSME UMR 8208 CNRS, France; 94010 Créteil cedex, France
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Deroost K, Lays N, Pham TT, Baci D, Van den Eynde K, Komuta M, Prato M, Roskams T, Schwarzer E, Opdenakker G, Van den Steen PE. Hemozoin induces hepatic inflammation in mice and is differentially associated with liver pathology depending on the Plasmodium strain. PLoS One 2014; 9:e113519. [PMID: 25419977 PMCID: PMC4242621 DOI: 10.1371/journal.pone.0113519] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2014] [Accepted: 10/29/2014] [Indexed: 12/26/2022] Open
Abstract
Malaria is a global disease that clinically affects more than two hundred million people annually. Despite the availability of effective antimalarials, mortality rates associated with severe complications are high. Hepatopathy is frequently observed in patients with severe malarial disease and its pathogenesis is poorly understood. Previously, we observed high amounts of hemozoin or malaria pigment in livers from infected mice. In this study, we investigated whether hemozoin is associated with liver injury in different mouse malaria models. C57BL/6J mice infected with the rodent parasites Plasmodium berghei ANKA, P. berghei NK65 or P. chabaudi AS had elevated serum liver enzymes without severe histological changes in the liver, in line with the observations in most patients. Furthermore, liver enzymes were significantly higher in serum of P. chabaudi AS-infected mice compared to mice infected with the P. berghei parasite strains and a strong positive correlation was found between hepatic hemozoin levels, hepatocyte damage and inflammation in the liver with P. chabaudi AS. The observed liver injury was only marginally influenced by the genetic background of the host, since similar serum liver enzyme levels were measured in infected C57BL/6J and BALB/c mice. Intravenous injection of P. falciparum-derived hemozoin in malaria-free C57BL/6J mice induced inflammatory gene transcription in the liver, suggesting that hemozoin may be involved in the pathogenesis of malaria hepatopathy by inducing inflammation.
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Affiliation(s)
- Katrien Deroost
- Department of Microbiology & Immunology, Laboratory of Immunobiology, Rega Institute for Medical Research, KU Leuven - University of Leuven, Leuven, Belgium
| | - Natacha Lays
- Department of Microbiology & Immunology, Laboratory of Immunobiology, Rega Institute for Medical Research, KU Leuven - University of Leuven, Leuven, Belgium
| | - Thao-Thy Pham
- Department of Microbiology & Immunology, Laboratory of Immunobiology, Rega Institute for Medical Research, KU Leuven - University of Leuven, Leuven, Belgium
| | - Denisa Baci
- Department of Oncology, University of Torino, Torino, Italy
- Department of Biology, Tor Vergata Rome University, Rome, Italy
| | | | - Mina Komuta
- Translational Cell & Tissue Research, KU Leuven – University of Leuven, Leuven, Belgium
| | - Mauro Prato
- Department of Neuroscience, University of Torino, Torino, Italy
| | - Tania Roskams
- Translational Cell & Tissue Research, KU Leuven – University of Leuven, Leuven, Belgium
| | - Evelin Schwarzer
- Department of Oncology, University of Torino, Torino, Italy
- Department of Genetics, Biology, and Biochemistry, University of Torino, Torino, Italy
| | - Ghislain Opdenakker
- Department of Microbiology & Immunology, Laboratory of Immunobiology, Rega Institute for Medical Research, KU Leuven - University of Leuven, Leuven, Belgium
| | - Philippe E. Van den Steen
- Department of Microbiology & Immunology, Laboratory of Immunobiology, Rega Institute for Medical Research, KU Leuven - University of Leuven, Leuven, Belgium
- * E-mail:
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Pham TT, Bonnevialle N, Rongières M, Bonnevialle P, Mansat P. Mechanical failure of the Coonrad-Morrey linked total elbow arthroplasty: A case report. Orthop Traumatol Surg Res 2014; 100:831-4. [PMID: 25262098 DOI: 10.1016/j.otsr.2014.07.013] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/10/2014] [Revised: 05/16/2014] [Accepted: 07/25/2014] [Indexed: 02/02/2023]
Abstract
Semiconstrained (linked design) total elbow arthroplasty is indicated in a wide variety of cases. Long-term survival is better than with non-linked prostheses. However, mechanical failure of the hinge mechanism is a complication that may occur during follow-up. We report a case of failure of the axle assembly of a Coonrad-Morrey elbow prosthesis 8 years after implantation for nonunion of a supracondylar distal humerus fracture. Initial revision surgery included changing the axle and the polyethylene bushings. Revision surgery was necessary 1 year later when the axle failed again. A custom-designed locking axle had to be used to stabilize the hinge mechanism. After 3 years follow-up, the hinge was intact, there was no loosening of the components and function of the elbow was good.
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Affiliation(s)
- T T Pham
- Institut de l'appareil locomoteur du CHU de Toulouse, Département d'Orthopédie et traumatologie, Hôpital Pierre-Paul-Riquet, place du Docteur-Baylac, 31059 Toulouse Cedex, France
| | - N Bonnevialle
- Institut de l'appareil locomoteur du CHU de Toulouse, Département d'Orthopédie et traumatologie, Hôpital Pierre-Paul-Riquet, place du Docteur-Baylac, 31059 Toulouse Cedex, France
| | - M Rongières
- Institut de l'appareil locomoteur du CHU de Toulouse, Département d'Orthopédie et traumatologie, Hôpital Pierre-Paul-Riquet, place du Docteur-Baylac, 31059 Toulouse Cedex, France
| | - P Bonnevialle
- Institut de l'appareil locomoteur du CHU de Toulouse, Département d'Orthopédie et traumatologie, Hôpital Pierre-Paul-Riquet, place du Docteur-Baylac, 31059 Toulouse Cedex, France
| | - P Mansat
- Institut de l'appareil locomoteur du CHU de Toulouse, Département d'Orthopédie et traumatologie, Hôpital Pierre-Paul-Riquet, place du Docteur-Baylac, 31059 Toulouse Cedex, France.
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22
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Nishijo M, Pham TT, Nguyen ATN, Tran NN, Nakagawa H, Hoang LV, Tran AH, Morikawa Y, Ho MD, Kido T, Nguyen MN, Nguyen HM, Nishijo H. 2,3,7,8-Tetrachlorodibenzo-p-dioxin in breast milk increases autistic traits of 3-year-old children in Vietnam. Mol Psychiatry 2014; 19:1220-6. [PMID: 24637425 DOI: 10.1038/mp.2014.18] [Citation(s) in RCA: 64] [Impact Index Per Article: 6.4] [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: 08/02/2013] [Revised: 01/18/2014] [Accepted: 02/03/2014] [Indexed: 01/29/2023]
Abstract
Dioxin levels in the breast milk of mothers residing near a contaminated former airbase in Vietnam remain much higher than in unsprayed areas, suggesting high perinatal dioxin exposure for their infants. The present study investigated the association of perinatal dioxin exposure with autistic traits in 153 3-year-old children living in a contaminated area in Vietnam. The children were followed up from birth using the neurodevelopmental battery Bayley-III. The high-2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) exposed groups (⩾3.5 pg per g fat) showed significantly higher Autism Spectrum Rating Scale (ASRS) scores for both boys and girls than the mild-TCDD exposed groups, without differences in neurodevelopmental scores. In contrast, the high total dioxin-exposed group, indicated by polychlorinated dibenzo-p-dioxins/furans (PCDDs/Fs)--the toxic equivalents (TEQ) levels⩾17.9 pg-TEQ per g fat, had significantly lower neurodevelopmental scores than the mild-exposed group in boys, but there was no difference in the ASRS scores. The present study demonstrates a specific impact of perinatal TCDD on autistic traits in childhood, which is different from the neurotoxicity of total dioxins (PCDDs/Fs).
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Affiliation(s)
- M Nishijo
- Department of Public Health, Kanazawa Medical University, Ishikawa, Japan
| | - T T Pham
- Biomedical and Pharmaceutical Research Center, Vietnam Military Medical University, Ha Noi, Vietnam
| | - A T N Nguyen
- Department of Public Health, Kanazawa Medical University, Ishikawa, Japan
| | - N N Tran
- Department of Public Health, Kanazawa Medical University, Ishikawa, Japan
| | - H Nakagawa
- Department of Public Health, Kanazawa Medical University, Ishikawa, Japan
| | - L V Hoang
- Biomedical and Pharmaceutical Research Center, Vietnam Military Medical University, Ha Noi, Vietnam
| | - A H Tran
- Biomedical and Pharmaceutical Research Center, Vietnam Military Medical University, Ha Noi, Vietnam
| | - Y Morikawa
- School of Nursing, Kanazawa Medical University, Ishikawa, Japan
| | - M D Ho
- Faculty of Health Sciences, Institute of Medical, Pharmaceutical and Health Sciences, Kanazawa University, Ishikawa, Japan
| | - T Kido
- Faculty of Health Sciences, Institute of Medical, Pharmaceutical and Health Sciences, Kanazawa University, Ishikawa, Japan
| | - M N Nguyen
- 1] Biomedical and Pharmaceutical Research Center, Vietnam Military Medical University, Ha Noi, Vietnam [2] System Emotional Science, Graduate School of Medicine and Pharmaceutical Science, University of Toyama, Toyama, Japan
| | - H M Nguyen
- 1] Biomedical and Pharmaceutical Research Center, Vietnam Military Medical University, Ha Noi, Vietnam [2] System Emotional Science, Graduate School of Medicine and Pharmaceutical Science, University of Toyama, Toyama, Japan
| | - H Nishijo
- System Emotional Science, Graduate School of Medicine and Pharmaceutical Science, University of Toyama, Toyama, Japan
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Rochelle-Newall EJ, Chu VT, Pringault O, Amouroux D, Arfi R, Bettarel Y, Bouvier T, Bouvier C, Got P, Nguyen TMH, Mari X, Navarro P, Duong TN, Cao TTT, Pham TT, Ouillon S, Torréton JP. Phytoplankton distribution and productivity in a highly turbid, tropical coastal system (Bach Dang Estuary, Vietnam). Mar Pollut Bull 2011; 62:2317-2329. [PMID: 21945560 DOI: 10.1016/j.marpolbul.2011.08.044] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/09/2011] [Revised: 08/26/2011] [Accepted: 08/31/2011] [Indexed: 05/31/2023]
Abstract
Phytoplankton diversity, primary and bacterial production, nutrients and metallic contaminants were measured during the wet season (July) and dry season (March) in the Bach Dang Estuary, a sub-estuary of the Red River system, Northern Vietnam. Using canonical correspondence analysis we show that phytoplankton community structure is potentially influenced by both organometallic species (Hg and Sn) and inorganic metal (Hg) concentrations. During March, dissolved methylmercury and inorganic mercury were important factors for determining phytoplankton community composition at most of the stations. In contrast, during July, low salinity phytoplankton community composition was associated with particulate methylmercury concentrations, whereas phytoplankton community composition in the higher salinity stations was more related to dissolved inorganic mercury and dissolved mono and tributyltin concentrations. These results highlight the importance of taking into account factors other than light and nutrients, such as eco-toxic heavy metals, in understanding phytoplankton diversity and activity in estuarine ecosystems.
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Affiliation(s)
- E J Rochelle-Newall
- ECOSYM, UMR 5119 (CNRS-IRD-UM2-IFREMER), Université Montpellier II, Case 093, Place Bataillon, 34095 Montpellier, France.
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Pham TT, Giesert F, Röthig A, Floss T, Kallnik M, Weindl K, Hölter SM, Ahting U, Prokisch H, Becker L, Klopstock T, Hrabé de Angelis M, Beyer K, Görner K, Kahle PJ, Vogt Weisenhorn DM, Wurst W. DJ-1-deficient mice show less TH-positive neurons in the ventral tegmental area and exhibit non-motoric behavioural impairments. Genes Brain Behav 2009; 9:305-17. [PMID: 20039949 DOI: 10.1111/j.1601-183x.2009.00559.x] [Citation(s) in RCA: 59] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Loss of function of DJ-1 (PARK7) is associated with autosomal recessive early-onset Parkinson's disease (PD), one of the major age-related neurological diseases. In this study, we extended former studies on DJ-1 knockout mice by identifying subtle morphological and behavioural phenotypes. The DJ-1 gene trap-induced null mutants exhibit less dopamine-producing neurons in the ventral tegmental area (VTA). They also exhibit slight changes in behaviour, i.e. diminished rearing behaviour and impairments in object recognition. Furthermore, we detected subtle phenotypes, which suggest that these animals compensate for the loss of DJ-1. First, we found a significant upregulation of mitochondrial respiratory enzyme activities, a mechanism known to protect against oxidative stress. Second, a close to significant increase in c-Jun N-terminal kinase 1 phosphorylation in old DJ-1-deficient mice hints at a differential activation of neuronal cell survival pathways. Third, as no change in the density of tyrosine hydroxylase (TH)-positive terminals in the striatum was observed, the remaining dopamine-producing neurons likely compensate by increasing axonal sprouting. In summary, the present data suggest that DJ-1 is implicated in major non-motor symptoms of PD appearing in the early phases of the disease-such as subtle impairments in motivated behaviour and cognition-and that under basal conditions the loss of DJ-1 is compensated.
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Affiliation(s)
- T T Pham
- Institute of Developmental Genetics, Helmholtz Zentrum München, German Research Center for Environmental Health, Ingolstaedter, Neuherberg, Germany
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Abstract
We study a system of grafted polymers in a poor solvent by self-consistent-field methods as well as Monte-Carlo simulation methods. We observe a number of different morphological structures including an inverted solvent micelle or hole in the polymer layer, a lamella-like micelle structure, and fused, spherical micelle structures. These structures can be obtained by either varying the grafting density or chain length. We also develop a scaling theory for the existence of these structures and find reasonable agreement between this theory and our numerical calculations.
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Affiliation(s)
- Sudip K Pattanayek
- School of Aerospace, Mechanical and Mechatronic Engineering, University of Sydney, Sydney 2006, Australia
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Abstract
We study a system of grafted semiflexible polymers in a poor solvent which form toroidal or rodlike conformations in the bulk. However, because of the physical constraint of surface grafting, macrophase separation is inhibited and a number of different polymer aggregates (or micelles) form which can be related to the chains' stiffness and their affinity for each other. In contrast to the fully flexible Gaussian case, we observe a number of novel micelle structures, including tower micelles, archway micelles, and spider micelles. We also attempt to develop a phase diagram for the occurrence of these structures with respect to the variables of chain length, chain stiffness, and polymer grafting density.
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Affiliation(s)
- T T Pham
- School of Aerospace, Mechanical and Mechatronic Engineering, University of Sydney, Australia
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Pham TT, Bouloudian S, Moreau PE, Mofid R, Garcier JM, Boyer L, Soubrier M. Recurrent hemarthrosis following total knee arthroplasty. Report of a case treated with arterial embolization. Joint Bone Spine 2003; 70:58-60. [PMID: 12639619 DOI: 10.1016/s1297-319x(02)00012-x] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.1] [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: 10/27/2022]
Abstract
Recurrent spontaneous hemarthrosis of the knee is common and often related to a detectable cause. In contrast, hemarthrosis after knee arthroplasty is rare and frequently unexplained. We report a case of recurrent hemarthrosis 6 years after total knee arthroplasty. The cause was hypervascularization about the joint, and embolization therapy was effective.
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Affiliation(s)
- T T Pham
- Radiology department, CHU Montpied, BP 69, 63003 Clermont-Ferrand cedex, France
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Gervaz P, Efron J, Poza AA, Chun SW, Pham TT, Woodhouse S, Wexner SD, Carethers JM. Loss of heterozygosity and HIV infection in patients with anal squamous-cell carcinoma. Dis Colon Rectum 2001; 44:1503-8. [PMID: 11598481 DOI: 10.1007/bf02234606] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
PURPOSE This study was designed to determine whether loss of heterozygosity and/or microsatellite instability correlate with HIV infection and tumor recurrence after chemoradiation therapy in patients with squamous-cell carcinoma of the anus. BACKGROUND The molecular mechanisms leading to the progression of HIV-related squamous-cell carcinoma of the anus are poorly understood. In particular, genetic alterations responsible for resistance to chemoradiation have important clinical and functional implications. METHODS In a case-control study, we analyzed normal and tumor DNA samples of four patients with squamous-cell carcinoma of the anus who were successfully treated with chemoradiotherapy and four patients with radio-resistant squamous-cell carcinoma of the anus who required abdominoperineal resection for local recurrence. To determine the presence of microsatellite instability, we used the reference panel of five pairs of microsatellite primers recommended for colorectal cancer specimens. These include the microsatellite markers BAT25, BAT26, D5S346 (APC), D2S123 (hMSH2), and D17S250 (P53). In addition, we used microsatellite markers for loss of heterozygosity analyses that were tightly linked to tumor suppressor genes. These included D3S1611 (hMLH1), D17S513 (P53), D18S46 and 18qTA (DCC/SMAD4), D5S107 (APC), and CA5 (hMSH2). RESULTS There were two HIV-positive and two HIV-negative patients in each group. Three HIV-positive patients (one in the chemoradiotherapy group and two in the nonchemoradiotherapy group) demonstrated loss of heterozygosity. In the chemoradiotherapy group, one HIV-positive patient demonstrated loss of heterozygosity at the hMLH1 locus. In the nonchemoradiotherapy group, two HIV-positive patients exhibited a total of four instances of loss of heterozygosity. One tumor had loss of heterozygosity at hMSH2 and DCC/SMAD4; another tumor demonstrated loss of heterozygosity at hMSH2 and APC. Microsatellite instability-low was found in two HIV-positive patients. No instances of loss of heterozygosity and microsatellite instability were detected in HIV-negative patients. CONCLUSION Loss of heterozygosity and microsatellite instability, which reflect inactivation of tumor-suppressor genes and genomic instability, occur with increased frequency in HIV-associated squamous-cell carcinoma. These data demonstrate for the first time evidence of loss of heterozygosity at the APC and DCC/SMAD4 gene loci in anal carcinoma. Although the findings presented here need to be expanded in a larger study, the recurrent loss of heterozygosity at D2S123, which was demonstrated in HIV-positive patients with radio-resistant squamous-cell carcinoma of the anus, is notable.
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Affiliation(s)
- P Gervaz
- Department of Colorectal Surgery, Cleveland Clinic Florida, Weston, Florida 33331, USA
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Heitz A, Hernandez JF, Gagnon J, Hong TT, Pham TT, Nguyen TM, Le-Nguyen D, Chiche L. Solution structure of the squash trypsin inhibitor MCoTI-II. A new family for cyclic knottins. Biochemistry 2001; 40:7973-83. [PMID: 11434766 DOI: 10.1021/bi0106639] [Citation(s) in RCA: 121] [Impact Index Per Article: 5.3] [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: 11/29/2022]
Abstract
The "knottin" fold is a stable cysteine-rich scaffold, in which one disulfide crosses the macrocycle made by two other disulfides and the connecting backbone segments. This scaffold is found in several protein families with no evolutionary relationships. In the past few years, several homologous peptides from the Rubiaceae and Violaceae families were shown to define a new structural family based on macrocyclic knottin fold. We recently isolated from Momordica cochinchinensis seeds the first known macrocyclic squash trypsin inhibitors. These compounds are the first members of a new family of cyclic knottins. In this paper, we present NMR structural studies of one of them, MCoTI-II, and of a beta-Asp rearranged form, MCoTI-IIb. Both compounds display similar and well-defined conformations. These cyclic squash inhibitors share a similar conformation with noncyclic squash inhibitors such as CPTI-II, and it is postulated that the main effect of the cyclization is a reduced sensitivity to exo-proteases. On the contrary, clear differences were detected with the three-dimensional structures of other known cyclic knottins, i.e., kalata B1 or circulin A. The two-disulfide cystine-stabilized beta-sheet motif [Heitz et al. (1999) Biochemistry 38, 10615-10625] is conserved in the two families, whereas in the C-to-N linker, one disulfide bridge and one loop are differently located. The molecular surface of MCoTI-II is almost entirely charged in contrast to circulin A that displays a well-marked amphiphilic character. These differences might explain why the isolated macrocyclic squash inhibitors from M. cochinchinensis display no significant antibacterial activity, whereas circulins and kalata B1 do.
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Affiliation(s)
- A Heitz
- Centre de Biochimie Structurale, UMR5048 CNRS-Université Montpellier I, UMR554 INSERM-Université Montpellier I, Faculté de pharmacie, 15 avenue Charles Flahault, 34060 Montpellier, France
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Huang SC, Lavine JE, Boland PS, Newbury RO, Kolodner R, Pham TT, Arnold CN, Boland CR, Carethers JM. Germline characterization of early-aged onset of hereditary non-polyposis colorectal cancer. J Pediatr 2001; 138:629-35. [PMID: 11343035 DOI: 10.1067/mpd.2001.113620] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
OBJECTIVES Hereditary non-polyposis colorectal cancer (HNPCC) is characterized by the early onset of colorectal cancer (approximately 40 years). Adolescent colorectal cancer is unusual in HNPCC families. We speculated that some DNA mismatch repair germline mutations might be associated with early onset of disease. STUDY DESIGN Genomic DNA was extracted from members of a kindred with virulent HNPCC fitting the Amsterdam Criteria for HNPCC and sequenced for 2 DNA mismatch repair genes, hMSH2 and hMLH1. A sigmoid adenocarcinoma from the 14-year-old proband was analyzed for highfrequency microsatellite instability and immunostained for DNA mismatch repair gene expression. RESULTS A germline mutation was identified at nucleotide 676 (codon 226) of the hMLH1 gene. The C to T transition created a nonsense mutation, truncating the hMLH1 protein. This mutation also alters the splice donor sequence, because nucleotide 676 is 2 base pairs from the 3' end of the exon 8. The proband's tumor demonstrated high-frequency microsatellite instability and displayed loss of hMLH1 expression, indicating bi-allelic inactivation of hMLH1. CONCLUSIONS A complex mutation of hMLH1 at codon 226 is associated with adolescent onset of colorectal cancer in an HNPCC family. Genetic screening of other suspected HNPCC families with unusually young members with cancer might reveal certain genotypes with particularly virulent forms of this disease.
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Affiliation(s)
- S C Huang
- Division of Gastroenterology and Nutrition, Department of Pediatrics, University of California, San Diego, California, USA
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31
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Huang SC, Chen CR, Lavine JE, Taylor SF, Newbury RO, Pham TT, Ricciardiello L, Carethers JM. Genetic heterogeneity in familial juvenile polyposis. Cancer Res 2000; 60:6882-5. [PMID: 11156385] [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] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/18/2023]
Abstract
Juvenile polyposis syndrome (JPS) is an autosomal dominant syndrome characterized by multiple gastrointestinal hamartomatous polyps in the absence of the extraintestinal features that are classic for other hamartomatous polyposis syndromes, such as Bannayan-Riley-Ruvalcaba syndrome (BRRS) and Cowden disease (CD). About 50% of BRRS and >80% of CD demonstrate germ-line mutations in the tumor suppressor and dual phosphatase, PTEN. Germ-line mutation of PTEN as a cause for JPS in a child is controversial because extraintestinal manifestations that would exclude JPS could appear after adolescence, altering the clinical diagnosis. Here, we investigated a family in which the 55-year-old father, who lacks thyroid or skin findings characteristic of CD, demonstrated a germ-line mutation in PTEN that was passed to identical twin daughters, who both manifested JPS. The mutation was a deletion of five bases beginning seven bases from the start of exon 4 of PTEN, which caused aberrant transcripts by reverse transcription-PCR that were absent from a normal individual. Thus, mutations in PTEN are associated with JPS in addition to CD and some BRRS families, although the incidence of PTEN germ-line mutations in JPS might be more rare than that reported for SMAD4, a gene found to be mutated in approximately one-half of the JPS families investigated.
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Affiliation(s)
- S C Huang
- Department of Pediatrics, Universitv of California, San Diego 92093, USA
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Hernandez JF, Gagnon J, Chiche L, Nguyen TM, Andrieu JP, Heitz A, Trinh Hong T, Pham TT, Le Nguyen D. Squash trypsin inhibitors from Momordica cochinchinensis exhibit an atypical macrocyclic structure. Biochemistry 2000; 39:5722-30. [PMID: 10801322 DOI: 10.1021/bi9929756] [Citation(s) in RCA: 280] [Impact Index Per Article: 11.7] [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: 11/28/2022]
Abstract
Three trypsin inhibitors (TIs), from the seeds of the squash Momordica cochinchinensis (MCo), have been isolated and purified using gel filtration, ion exchange chromatography, and reverse-phase HPLC. Their sequences could be determined only after proteolytic cleavages. In the case of MCoTI-I and -II, it was shown that their polypeptide backbones are cyclic, a structure that has never been described in squash TIs. They contain 34 amino acid residues with 3 disulfide bridges and measured molecular masses of 3453.0 and 3480.7, respectively. They are the largest known macrocyclic peptides containing disulfide bridges. Their sequences show strong homology to other squash TIs, suggesting a similar three-dimensional structure and an analogous mechanism of action. A model of MCoTI-II was constructed by analogy to the crystal structure of the complex between bovine trypsin and CMTI-I, indicating that the linker connecting the two termini is flexible and does not impose significant geometrical constraints. This flexibility allows an Asp-Gly peptide bond rearrangement to occur in this region, giving rise to two isoforms of MCoTI-II. Although the importance of cyclization is not clear, it might confer increased stability and resistance to proteolysis. A minor species, MCoTI-III, was also characterized as containing 30 amino acid residues with a molecular mass of 3379.6. This component possesses a linear backbone with a blocked N-terminus. MCoTIs represent interesting candidates for drug design, either by changing their specificity of inhibition or by using their structure as natural scaffolds bearing new binding activities.
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Affiliation(s)
- J F Hernandez
- Institut de Biologie Structurale Jean-Pierre Ebel (CEA-CNRS), 41, rue Jules Horowitz, 38027 Grenoble Cedex 1, France
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Carethers JM, Pham TT. Mutations of transforming growth factor beta 1 type II receptor, BAX, and insulin-like growth factor II receptor genes in microsatellite unstable cell lines. In Vivo 2000; 14:13-20. [PMID: 10757056] [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] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/16/2023]
Abstract
Inactivation of the DNA mismatch repair (MMR) system allows the genome to accumulate mutations because of failure to correct mispairing of nucleotides and slippage mistakes at microsatellite sequences (termed microsatellite instability ¿MSI¿). While most mutations are acquired in noncoding regions by virtue of its larger share of DNA, mutations may occur in exons of genes that contain microsatellite sequences. The type II receptor for TGF beta 1 (TGF beta RII), the insulin-like growth factor II receptor (IGFIIR), and the proapoptotic gene BAX have been shown to contain mononucleotide microsatellites, and in MSI tumors, mutations may occur in these sequences late in the multistep carcinogenesis pathway. Here, we characterize 9 cell lines for MSI and mutations in TGF beta RII, BAX, and IGFIIR by PCR-based assays. The MMR-proficient cell lines SW480 and HT29 demonstrate stability at microsatellite sequences and do not have mutations in TGF beta RII, BAX, or IGFIIR. The MMR-deficient cell lines LoVo, SW48, LS174t, and HCT116 all demonstrate MSI and have only mutant alleles of TGF beta RII. Additionally, SW48 cells were heterozygous for wild-type and mutant IGFIIR. While LoVo and LS174t cells possessed only mutant BAX alleles, HCT116 was heterozygous and SW48 had only the wild-type allele. The MMR-deficient ovarian cell line 2774 demonstrated MSI, but showed only wild-type TGF beta RII, IGFIIR, and BAX alleles. In HCT116+ch2 cells, there was no genotypic change from the hMLH1-mutated HCT116 cells. In HCT116+ch3 cells, MSI was corrected, and this cell line became heterozygous for mutant and wild-type TGF beta RII because wild-type hMLH1 and TGF beta RII are both located on chromosome 3. Thus, the presence of a defective MMR system correlates with MSI, and the wild-type allele of TGF beta RII was absent in all microsatellite unstable colon cell lines, whereas the absence of wild-type BAX occurred in only two colon cell lines. In ovarian cancer cells with MSI, mutations in TGF beta RII, BAX, and IGFIIR may be unimportant in the genesis of this tumor.
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Affiliation(s)
- J M Carethers
- Department of Medicine and Cancer Center, University of California, San Diego, USA.
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Michael LH, Ballantyne CM, Zachariah JP, Gould KE, Pocius JS, Taffet GE, Hartley CJ, Pham TT, Daniel SL, Funk E, Entman ML. Myocardial infarction and remodeling in mice: effect of reperfusion. Am J Physiol 1999; 277:H660-8. [PMID: 10444492 DOI: 10.1152/ajpheart.1999.277.2.h660] [Citation(s) in RCA: 63] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Anatomic and functional changes after either a permanent left anterior descending coronary artery occlusion (PO) or 2 h of occlusion followed by reperfusion (OR) in C57BL/6 mice were examined and compared with those in sham-operated mice. Both interventions generated infarcts comprising 30% of the left ventricle (LV) measured at 24 h and equivalent suppression of LV ejection velocity and filling velocity measured by Doppler ultrasound at 1 wk. Serial follow-up revealed that the ventricular ejection velocity and filling velocity returned to the levels of the sham-operated controls in the OR group at 2 wk and remained there; in contrast, PO animals continued to display suppression of both systolic and diastolic function. In contrast, ejection fractions of PO and OR animals were depressed equivalently (50% from sham-operated controls). Anatomic reconstruction of serial cross sections revealed that the percentage of the LV endocardial area overlying the ventricular scar (expansion ratio) was significantly larger in the PO group vs. the OR group (18 +/- 1.7% vs. 12 +/- 0.9%, P < 0.05). The septum that was never involved in the infarction had a significantly (P < 0.002) increased mass in PO animals (22.5 +/- 1.08 mg) vs. OR (17.8 +/- 1.10 mg) or sham control (14.8 +/- 0.99 mg) animals. Regression analysis demonstrated that the extent of septal hypertrophy correlated with LV expansion ratio. Thus late reperfusion appears to reduce the degree of infarct expansion even under circumstances in which it no longer can alter infarct size. We suggest that reperfusion promoted more effective ventricular repair, less infarct expansion, and significant recovery or preservation of ventricular function.
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Affiliation(s)
- L H Michael
- DeBakey Heart Center and Department of Medicine, Baylor College of Medicine, Houston, Texas 77030-3498, USA.
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Quémerais B, Cossa D, Rondeau B, Pham TT, Fortin B. Mercury distribution in relation to iron and manganese in the waters of the St. Lawrence river. Sci Total Environ 1998; 213:193-201. [PMID: 9652128 DOI: 10.1016/s0048-9697(98)00092-8] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
Waters entering the St. Lawrence River from Lake Ontario and from the Ottawa River have been sampled on a quaternary basis between March 1995 and October 1996. Mercury, iron, manganese, organic carbon and other chemical parameters have been determined in the filtered water (< 0.5 micron) and suspended particles (> 0.5 micron). Average total mercury concentrations (+/- standard deviation, number of determinations) in filtered samples were 1.3 +/- 0.9 pM (39) at the mouth of Lake Ontario and 4.0 +/- 2.3 pM (54) at the outlet of the Ottawa River. The respective average concentrations in suspended particles were 1.1 +/- 0.4 (39) and 0.6 +/- 0.2 (55) nmol g-1. Partial correlation analyses reveal that in the fraction < 0.5 micron--which seems to consist of a significant fraction of colloids--mercury was significantly linked to iron, while in the particulate phase, mercury was related to manganese. Mercury was not correlated with organic carbon. A sorption model on iron and manganese hydroxides is proposed to explain these observations.
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Affiliation(s)
- B Quémerais
- St. Lawrence Centre, Environment Canada, Montréal, Qué, Canada.
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36
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Taffet GE, Pham TT, Hartley CJ. The age-associated alterations in late diastolic function in mice are improved by caloric restriction. J Gerontol A Biol Sci Med Sci 1997; 52:B285-90. [PMID: 9402929 DOI: 10.1093/gerona/52a.6.b285] [Citation(s) in RCA: 79] [Impact Index Per Article: 2.9] [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: 02/05/2023] Open
Abstract
Caloric restriction reduces the magnitude of many age-related changes in rodents. Cardiac function is altered with senescence in mice, rats, and healthy humans. We examined the effects of life-long caloric restriction on diastolic and systolic cardiac function in situ using Doppler techniques in ad libitum-fed 30- to 32-month-old (AL) and calorically restricted (CR) 32- to 35-month-old female B6D2-F1 hybrid mice. The heart weight to body weight ratio was similar in AL (5.74 +/- .24 mg/g) and CR (5.68 +/- .20 mg/g) mice. Two systolic functional parameters known to decrease with age in both humans and mice, peak aortic velocity and aortic acceleration, were unchanged by CR compared to AL. In contrast, diastolic function was altered by caloric restriction. Although left ventricular peak early filling velocity (E) was not different between CR and AL, peak atrial filling velocity (A) was 50% lower in CR compared to AL (p < .001). The ratio of early diastolic filling to atrial filling (E/A ratio) was 64% higher in the CR (2.74 +/- .31) than the AL (1.55 +/- .07; p = .004). The fraction of ventricular filling due to atrial systole, the atrial filling fraction, was also reduced in CR (.21 +/- .04) compared to AL (.36 +/- .02; p = .007). These changes occurred in CR without alteration in E deceleration time, which is consistent with improved diastolic function in CR. Through mechanisms that remain unknown, lifelong caloric restriction may prevent the age-related impairments in late diastolic function but does not alter the impairments in systolic or early diastolic cardiac function.
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Affiliation(s)
- G E Taffet
- Section of Cardiovascular Sciences, Baylor College of Medicine, Houston, USA
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Abstract
Some transgenic mice have abnormal vascular function, but arterial geometry and dynamics are difficult to evaluate. To examine whether ultrasonic velocimetry could be used to determine arterial pulse-wave velocity (PWV) in mice, a custom-made 20-MHz pulsed Doppler instrument was used to obtain blood flow velocity signals from the aortic arch and the abdominal aorta 4 cm downstream. The upstroke (foot) of the velocity wave was timed at each site with respect to the R wave of the electrocardiogram, and PWV was calculated by dividing the separation distance by the difference in R-foot times. Doppler determinations were compared with invasive tonometry, and PWV was altered pharmacologically. It was found that the upstrokes of pressure (by tonometry) and velocity were coincident (+/-1 ms) and that PWV could be calculated by either method on exposed vessels. With the use of Doppler methods, pulse transit time was determined noninvasively with +/-1-ms resolution in 140 of 142 attempts in 82 mice. The calculated PWV in mice ranged from 220 to 850 cm/s with vasodilating anesthetics producing the low values and vasoconstricting agents producing the higher values. Thus PWV can be determined noninvasively in mice, is similar to that in other mammals, and responds as expected to vasoactive agents.
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Affiliation(s)
- C J Hartley
- Department of Medicine, Baylor College of Medicine, Houston, Texas 77030, USA
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Cao XT, Bethell DB, Pham TP, Ta TT, Tran TN, Nguyen TT, Pham TT, Nguyen TT, Day NP, White NJ. Comparison of artemisinin suppositories, intramuscular artesunate and intravenous quinine for the treatment of severe childhood malaria. Trans R Soc Trop Med Hyg 1997; 91:335-42. [PMID: 9231212 DOI: 10.1016/s0035-9203(97)90099-7] [Citation(s) in RCA: 66] [Impact Index Per Article: 2.4] [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] Open
Abstract
Severe malaria remains a major cause of mortality and morbidity for children living in many tropical regions. With the emergence of strains of Plasmodium falciparum resistant to both chloroquine and quinine, alternative antimalarial agents are required. The artemisinin group of compounds are rapidly effective in severe disease when given by intramuscular or intravenous injection. However, these routes of administration are not always available in rural areas. In an open, randomized comparison 109 Vietnamese children, aged between 3 months and 14 years, with severe P.falciparum malaria, were allocated at random to receive artemisinin suppositories followed by mefloquine (n = 37), intramuscular artesunate followed by mefloquine (n = 37), or intravenous quinine followed by pyrimethamine/sulfadoxine (n = 35). There were 9 deaths: 2 artemisinin, 4 artesunate and 5 quinine-treated children. There was no difference in fever clearance time, coma recovery, or length of hospital stay among the 3 groups. However, parasite clearance times were significantly faster in artemisinin and artesunate-treated patients than in those who received quinine (P < 0.0001). Both artemisinin and artesunate were very well tolerated, but children receiving these drugs had lower peripheral reticulocyte counts by day 5 of treatment than those in the quinine group (P = 0.011). No other adverse effect or toxicity was found. There was no treatment failure in these 2 groups, but 4 patients in the quinine group failed to clear their parasites within 7 d of starting treatment and required alternative antimalarial therapy. Artemisinin suppositories are easy to administer, cheap, and very effective for treating children with severe malaria. In rural areas where medical facilities are lacking these drugs will allow antimalarial therapy to be instituted earlier in the course of the disease and may therefore save lives.
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Affiliation(s)
- X T Cao
- Dong Nai Paediatric Centre, Bien Hoa, Viet Nam
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Bethell DB, Teja-Isavadharm P, Cao XT, Pham TT, Ta TT, Tran TN, Nguyen TT, Pham TP, Kyle D, Day NP, White NJ. Pharmacokinetics of oral artesunate in children with moderately severe Plasmodium falciparum malaria. Trans R Soc Trop Med Hyg 1997; 91:195-8. [PMID: 9196768 DOI: 10.1016/s0035-9203(97)90222-4] [Citation(s) in RCA: 46] [Impact Index Per Article: 1.7] [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: 02/04/2023] Open
Abstract
The pharmacokinetic properties of oral artesunate (3 mg/kg) were determined in 10 Vietnamese children, aged from 6 to 15 years, with acute falciparum malaria of moderate severity. Plasma concentrations were measured using a bioassay and expressed in terms of antimalarial activity equivalent to dihydroartemisinin, the principal biologically active metabolite. Oral artesunate was absorbed rapidly with a mean time to peak plasma bioactivity of 1.7 h (95% confidence interval [95% CI] 0.8-2.6). There was wide variation in peak plasma concentrations with a mean value equivalent to 664 ng of dihydroartemisinin/mL (95% CI 387-9410, range 179-1395) and a four-fold variation in the area under the plasma concentration-time curves. Elimination from plasma was rapid with a mean (95% CI) half-life of 1.0 h (95% CI 0.8-1.4). Plasma antimalarial levels were below the limit of detection in all cases by 12 h, despite the relatively high dose of artesunate used. Oral artesunate is rapidly absorbed and rapidly eliminated in children with moderately severe malaria but there is considerable variation between individuals.
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Affiliation(s)
- D B Bethell
- Wellcome Trust Clinical Research Unit, Centre for Tropical Diseases, Cho Quan Hospital, Ho Chi Minh City, Viet Nam
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Pham TT, Chillapagari S, Suarez AR. Preparation of pure plasmid or cosmid DNA using single-strand affinity matrix and gel-filtration spin columns. Biotechniques 1996; 20:492-7. [PMID: 8679211 DOI: 10.2144/19962003492] [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: 02/01/2023] Open
Abstract
A rapid method has been developed for ultrapure plasmid or cosmid DNA isolation from ten-mL to several hundred-mL cultures of Escherichia coli (midi to maxi prep). A cleared lysate is prepared by alkaline lysis, followed by a quick alcohol precipitation step. Denatured bacterial DNA and RNA having at least 20 nucleotides of single-stranded regions are removed from the supercoiled plasmid by binding strongly to the single-strand affinity matrix (SSAMTM). Plasmid DNA is then effectively purified on a gel-filtration spin column to remove SSAM, proteins, small RNA and salts. This method produces consistent yields of high-quality plasmids that are suitable for use in many molecular biology applications. In addition, recombinant cosmids of approximately 46 kb can be purified intact, free of chromosomal DNA.
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Affiliation(s)
- T T Pham
- CLONTECH Laboratories, Inc., Palo Alto, CA, USA
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Tran TH, Bethell DB, Nguyen TT, Wain J, To SD, Le TP, Bui MC, Nguyen MD, Pham TT, Walsh AL. Short course of ofloxacin for treatment of multidrug-resistant typhoid. Clin Infect Dis 1995; 20:917-23. [PMID: 7795095] [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] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
In recent years, multiresistant strains of Salmonella typhi have emerged in many tropical countries. These strains remain highly sensitive to the fluoroquinolone antibiotics, although use of these drugs by children is considered contraindicated because of their reported toxicity in the cartilage of experimental animals. In a paired, open, randomized study during an epidemic of multidrug-resistant typhoid in southern Vietnam, two short-course ofloxacin regimens (15 mg/kg daily for 3 days and 10 mg/kg daily for 5 days) were compared for the treatment of uncomplicated typhoid fever. Of 438 patients enrolled (of whom 286 were < or = 14 years old), 228 had blood cultures positive for Salmonella species (S. typhi, 207; S. paratyphi A, 19; and S. choleraesuis, 2). There was one treatment failure in a patient who took only one dose of ofloxacin. Otherwise, both regimens were completely effective; there were no proven carriers, and there was no evidence of toxicity, particularly in children. A 3-day course of ofloxacin proved to be safe and highly effective in the treatment of uncomplicated, multidrug-resistant typhoid fever.
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Affiliation(s)
- T H Tran
- Centre for Tropical Diseases, Cho Quan Hospital, Ho Chi Minh City, Vietnam
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Taffet GE, Pham TT, Bick DL, Entman ML, Pownall HJ, Bick RJ. The calcium uptake of the rat heart sarcoplasmic reticulum is altered by dietary lipid. J Membr Biol 1993; 131:35-42. [PMID: 8381872 DOI: 10.1007/bf02258532] [Citation(s) in RCA: 41] [Impact Index Per Article: 1.3] [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: 01/30/2023]
Abstract
Small amounts of dietary n-3 fatty acids can have dramatic physiological effects, including the reduction of plasma triglycerides and an elevation of cellular eicosapentanoic (EPA) and docosahexanoic acids (DHA) at the expense of arachidonic acid (AA). We investigated the effects of alterations in the fatty acid compositions of cardiac sarcoplasmic reticulum (CSR) produced by dietary manipulation on the calcium pump protein that is required for energy dependent calcium transport. CSR was isolated from rats fed menhaden oil, which is rich in n-3 fatty acids, and from control animals that were given corn oil. Relative to control membranes, those isolated from rats fed menhaden oil, had a lower content of saturated phospholipids, an increased DHA/AA ratio, and an increased ratio of n-3 to n-6 fatty acids. These changes were associated with a 30% decrease in oxalate-facilitated, ATP-dependent calcium uptake and concomitant decreased Ca-ATPase activity in the membranes from the animals fed menhaden oil. In contrast, there was no alteration in active pump sites as measured by phosphoenzyme formation. Thus, the CSR Ca-ATPase function can be altered by dietary interventions that change the composition, and possibly structure, of the phospholipid membranes thereby affecting enzyme turnover.
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Affiliation(s)
- G E Taffet
- Department of Medicine, Baylor College of Medicine, Houston, Texas
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Nakasato SK, Pham TT, Berman SM. Impact of treatment guidelines on the use of aerosolized pentamidine for prevention of Pneumocystis carinii pneumonia. Am J Hosp Pharm 1991; 48:2440-2. [PMID: 1746581] [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] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
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44
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King GC, Martin CT, Pham TT, Coleman JE. Transcription by T7 RNA polymerase is not zinc-dependent and is abolished on amidomethylation of cysteine-347. Biochemistry 1986; 25:36-40. [PMID: 3082355 DOI: 10.1021/bi00349a006] [Citation(s) in RCA: 68] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
T7 RNA polymerase has been purified to homogeneity from an overproducing clone of Escherichia coli containing pAR1219. Preparations have a zinc content as low as 0.01 mol/mol of enzyme and a high specific activity, 300 000-500 000 units/mg. There are no intrinsic zinc sites. Furthermore, extrinsic Zn2+ does not function as an activator. Supplementation of the assay mix with up to 5 mM ethylenediaminetetraacetic acid has little effect on activity while added Zn2+ is strongly inhibitory at concentrations above 10 microM. This monomeric RNA polymerase is not a zinc metalloenzyme, unlike its multimeric bacterial counterparts. Titration of the urea-denatured protein with 5,5'-dithiobis(2-nitrobenzoic acid) reveals that all 12 Cys residues are present in the free sulfhydryl form, 5 of which are readily accessible to reagent in the native enzyme. More preferential labeling of the sulfhydryls can be achieved with low concentrations of [14C]iodoacetamide, where inactivation of the enzyme proceeds with incorporation of approximately 1.2 mol of [14C]iodoacetamide/mol of polymerase. Amidomethylation primarily occurs at Cys-347, with lesser reaction at Cys-723 and Cys-839. Cys-347 and Cys-723 are in segments of the primary sequence containing numerous basic residues. These same segments have previously been implicated in promoter binding, suggesting that both residues are located within or near the active site region.
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Abstract
The structural gene for the single-stranded endonuclease coded for by gene 3 of bacteriophage T7 has been cloned in pGW7, a derivative of the plasmid pBR322, which contains the lambda PL promoter and the gene for the temperature-sensitive lambda repressor, cI857. The complete gene 3 DNA sequence has been placed downstream of the PL promoter, and the endonuclease is overproduced by temperature induction at mid-log phase of Escherichia coli carrying the recombinant plasmid pTP2. Despite the fact that cell growth rapidly declines due to toxic effects of the excess endonuclease, significant amounts of the enzyme can be isolated in nearly homogeneous form from the induced cells. An assay of nuclease activity has been devised using gel electrophoresis of the product DNA fragments from DNA substrates. These assays show the enzyme to have an absolute requirement for Mg(II) (10 mM), a broad pH optimum near pH 7, but significant activity from pH 3 to pH 9, and a 10-100-fold preference for single-stranded DNA (ssDNA). The enzyme is readily inactivated by ethylenediaminetetraacetic acid or high salt. The differential activity in favor of ssDNA can be exploited to map small single-stranded regions in double-stranded DNAs as shown by cleavage of the melted region of an open complex of T7 RNA polymerase and its promoter.
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46
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Orlov VM, Ivashchuk AG, Iartsev SS, Pham TT. [Pyromecaine in the therapy of disorders of the heart rhythm]. Klin Med (Mosk) 1985; 63:38-9. [PMID: 3990186] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
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47
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Ton DL, Ha TK, Chu MK, Nguyen TN, Pham TT. Blood coagulation monitoring and anticoagulant therapy after liver resection: brief report. Crit Care Med 1984; 12:1071-2. [PMID: 6510004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
In this sample of 140 patients undergoing hepatic resection to remove cancerous tissue, hypercoagulation was the most common postoperative BCD; in ten patients, this complication led to hepatic failure and hepatic coma. These findings differ from those previously reported in the literature, possibly because our patients had advanced hepatomas which had already infiltrated the great vessels of the liver, and/or the remaining liver was seriously cirrhotic. We found that blood-coagulation monitoring and anticoagulation therapy yielded encouraging results, and it is our hope that this treatment in combination with immunotherapy will prolong the survival of these patients.
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