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Minete NFA, Oliveira RTG, Borges DP, Melo MML, Teixeira MC, Cavalcante CBA, Araújo MA, Melo RPM, Magalhães SMM, Pinheiro RF. THROMBOSIS DURING VENETOCLAX TREATMENT FOR ACUTE MYELOID LEUKEMIA WITH THE 3Q21Q26 SYNDROME: CRITICAL SURVEILLANCE URGENTLY NEEDED. Hematol Transfus Cell Ther 2022. [DOI: 10.1016/j.htct.2022.09.284] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
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Fernandes GDS, Braghiroli MI, Artioli M, Paterlini ACCR, Teixeira MC, Gumz BP, Girardi DDM, Braghiroli OFM, Costa FP, Hoff PM. Combination of Irinotecan, Oxaliplatin and 5-Fluorouracil as a Rechallenge Regimen for Heavily Pretreated Metastatic Colorectal Cancer Patients. J Gastrointest Cancer 2019; 49:470-475. [PMID: 28884286 DOI: 10.1007/s12029-017-0001-3] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [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] [Indexed: 12/15/2022]
Abstract
PURPOSE Our objective was to evaluate the benefit of re-exposing patients with refractory metastatic colorectal cancer (mCRC) to a combination of oxaliplatin, irinotecan and 5-fluorouracil treatment. METHODS We retrospectively analysed patients with mCRC who received a combination of oxaliplatin, irinotecan and fluorouracil as a rechallenge regimen after progressing on the same drugs. Both FOLFOXIRI and FOLFIRINOX were used. Toxicity was evaluated for each treatment cycle, and survival analysis was performed using the Kaplan-Meier method. RESULTS A total of 21 patients who were treated between January 2011 and December 2013 were selected for this study. Most of the patients (95.2%) had an ECOG status of 0-1. The median age at diagnosis was 52.1 years (range 36-77 years), and 14 (66.6%) patients had wild-type KRAS. Thirteen patients received FOLFIRINOX, and eight received FOLFOXIRI. Most patients had previously received at least three regimens, with 80% receiving anti-VEGF and 66% anti-EGFR antibodies. The response rate was 38%, and 24% patients had stable disease. The median time to disease progression was 4.0 months (range 1.0-9.1 months), and the median overall survival duration was 8.6 months (range 6.3-11.5 months). Most patients required dose adjustment and treatment delays. One patient experienced grade 5 neutropenic sepsis. CONCLUSIONS Both FOLFIRINOX and FOLFOXIRI are active and potentially feasible rechallenge treatment options for heavily pretreated patients with good performance status. With dose reduction and close monitoring for toxicity, the risk of serious adverse events can be minimised.
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Affiliation(s)
| | - Maria Ignez Braghiroli
- Hospital Sírio-Libanês, São Paulo, Brazil
- Instituto do Câncer do Estado de São Paulo, Universidade de São Paulo, São Paulo, Brazil
| | | | | | | | - Brenda Pires Gumz
- Hospital Sírio-Libanês, SGAS 613-conjunto E lote 95-Asa Sul, Brasília, DF, 70200-001, Brazil
| | - Daniel da Motta Girardi
- Hospital Sírio-Libanês, SGAS 613-conjunto E lote 95-Asa Sul, Brasília, DF, 70200-001, Brazil
| | | | | | - Paulo M Hoff
- Hospital Sírio-Libanês, São Paulo, Brazil
- Instituto do Câncer do Estado de São Paulo, Universidade de São Paulo, São Paulo, Brazil
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Pimentel-Moral S, Teixeira MC, Fernandes AR, Arráez-Román D, Martínez-Férez A, Segura-Carretero A, Souto EB. Lipid nanocarriers for the loading of polyphenols - A comprehensive review. Adv Colloid Interface Sci 2018; 260:85-94. [PMID: 30177215 DOI: 10.1016/j.cis.2018.08.007] [Citation(s) in RCA: 72] [Impact Index Per Article: 12.0] [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: 05/03/2018] [Revised: 08/22/2018] [Accepted: 08/22/2018] [Indexed: 01/01/2023]
Abstract
Polyphenols are secondary metabolites found in all vascular plants and constitute a large group of at least 10,000 unique compounds. Particular attention is currently being paid to polyphenols attributed to their beneficial effects in the protection and prevention of several diseases. While their use in food, pharmaceutical and cosmetic industries is largely documented, several environmental conditions (e.g. light, temperature or oxygen) may affect the physicochemical stability of polyphenols, compromising their bioactivity in vivo. To overcome these limitations, the loading of polyphenols into nanoparticles has been proposed aiming at both increasing their bioavailability and reducing eventual side effects. Lipid nanoparticles offer several advantages, namely their biodegradability and low toxicity, with the additional capacity to modify the release profile of loaded drugs. This paper is a review of the recent advances of lipid nanocarriers commonly used for the encapsulation of polyphenols, highlighting their added value to increase bioavailability and bioactivity of this group of compounds as well as their application in several diseases.
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Affiliation(s)
- S Pimentel-Moral
- Department of Analytical Chemistry, University of Granada, 18071 Granada, Spain; Research and Development Centre for Functional Food (CIDAF), Health Science Technological Park, 18016 Granada, Spain; Department of Pharmaceutical Technology, Faculty of Pharmacy, University of Coimbra (FFUC), Pólo das Ciências da Saúde, Azinhaga de Santa Comba, 3000-548 Coimbra, Portugal.
| | - M C Teixeira
- Department of Pharmaceutical Technology, Faculty of Pharmacy, University of Coimbra (FFUC), Pólo das Ciências da Saúde, Azinhaga de Santa Comba, 3000-548 Coimbra, Portugal; REQUIMTE/LAQV, Group of Pharmaceutical Technology, Faculty of Pharmacy, University of Coimbra, Coimbra, Portugal
| | - A R Fernandes
- Department of Pharmaceutical Technology, Faculty of Pharmacy, University of Coimbra (FFUC), Pólo das Ciências da Saúde, Azinhaga de Santa Comba, 3000-548 Coimbra, Portugal; REQUIMTE/LAQV, Group of Pharmaceutical Technology, Faculty of Pharmacy, University of Coimbra, Coimbra, Portugal
| | - D Arráez-Román
- Department of Analytical Chemistry, University of Granada, 18071 Granada, Spain; Research and Development Centre for Functional Food (CIDAF), Health Science Technological Park, 18016 Granada, Spain.
| | - A Martínez-Férez
- Chemical Engineering Department, University of Granada, 18071 Granada, Spain.
| | - A Segura-Carretero
- Department of Analytical Chemistry, University of Granada, 18071 Granada, Spain; Research and Development Centre for Functional Food (CIDAF), Health Science Technological Park, 18016 Granada, Spain.
| | - E B Souto
- Department of Pharmaceutical Technology, Faculty of Pharmacy, University of Coimbra (FFUC), Pólo das Ciências da Saúde, Azinhaga de Santa Comba, 3000-548 Coimbra, Portugal; REQUIMTE/LAQV, Group of Pharmaceutical Technology, Faculty of Pharmacy, University of Coimbra, Coimbra, Portugal.
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Teixeira MC, Carbone C, Souto EB. Beyond liposomes: Recent advances on lipid based nanostructures for poorly soluble/poorly permeable drug delivery. Prog Lipid Res 2017; 68:1-11. [PMID: 28778472 DOI: 10.1016/j.plipres.2017.07.001] [Citation(s) in RCA: 103] [Impact Index Per Article: 14.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2017] [Revised: 07/28/2017] [Accepted: 07/30/2017] [Indexed: 01/03/2023]
Abstract
Solid lipid nanoparticle (SLN), nanostructured lipid carriers (NLC) and hybrid nanoparticles, have gained increasing interest as drug delivery systems because of their potential to load and release drugs from the Biopharmaceutical classification system (BCS) of class II (low solubility and high permeability) and of class IV (low solubility and low permeability). Lipid properties (e.g. high solubilizing potential, biocompatibility, biotolerability, biodegradability and distinct route of absorption) contribute for the improvement of the bioavailability of these drugs for a set of administration routes. Their interest continues to grow, as translated by the number of patents being field worldwide. This paper discusses the recent advances on the use of SLN, NLC and lipid-polymer hybrid nanoparticles for the loading of lipophilic, poorly water-soluble and poorly permeable drugs, being developed for oral, topical, parenteral and ocular administration, also discussing the industrial applications of these systems. A review of the patents filled between 2014 and 2017, concerning the original inventions of lipid nanocarriers, is also provided.
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Affiliation(s)
- M C Teixeira
- Department of Pharmaceutical Technology, Faculty of Pharmacy, University of Coimbra (FFUC), Pólo das Ciências da Saúde, Azinhaga de Santa Comba, 3000-548 Coimbra, Portugal; REQUIMTE/LAQV, Group of Pharmaceutical Technology, Faculty of Pharmacy, University of Coimbra, Coimbra, Portugal
| | - C Carbone
- Department of Pharmaceutical Technology, Faculty of Pharmacy, University of Coimbra (FFUC), Pólo das Ciências da Saúde, Azinhaga de Santa Comba, 3000-548 Coimbra, Portugal; Laboratory of Drug Delivery Technology, Dept. of Drug Sciences, University of Catania, Catania, Italy
| | - E B Souto
- Department of Pharmaceutical Technology, Faculty of Pharmacy, University of Coimbra (FFUC), Pólo das Ciências da Saúde, Azinhaga de Santa Comba, 3000-548 Coimbra, Portugal; REQUIMTE/LAQV, Group of Pharmaceutical Technology, Faculty of Pharmacy, University of Coimbra, Coimbra, Portugal.
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Teixeira MC, Severino P, Andreani T, Boonme P, Santini A, Silva AM, Souto EB. d-α-tocopherol nanoemulsions: Size properties, rheological behavior, surface tension, osmolarity and cytotoxicity. Saudi Pharm J 2016; 25:231-235. [PMID: 28344473 PMCID: PMC5355551 DOI: 10.1016/j.jsps.2016.06.004] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.0] [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: 04/19/2016] [Accepted: 06/16/2016] [Indexed: 10/26/2022] Open
Abstract
The aim of this study was the assessment of the physicochemical stability of d-α-tocopherol formulated in medium chain triglyceride nanoemulsions, stabilized with Tween®80 and Lipoid®S75 as surfactant and co-surfactant, respectively. d-α-tocopherol was selected as active ingredient because of its well-recognized interesting anti-oxidant properties (such as radical scavenger) for food and pharmaceutical industries. A series of nanoemulsions of mean droplet size below 90 nm (polydispersity index < 0.15) have been produced by high-pressure homogenization, and their surface electrical charge (zeta potential), pH, surface tension, osmolarity, and rheological behavior, were characterized as a function of the d-α-tocopherol loading. In vitro studies in Caco-2 cell lines confirmed the safety profile of the developed nanoemulsions with percentage of cell viability above 90% for all formulations.
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Affiliation(s)
- M C Teixeira
- Department of Pharmaceutical Technology, Faculty of Pharmacy, University of Coimbra (FFUC), Pólo das Ciências da Saúde, Azinhaga de Santa Comba, 3000-548 Coimbra, Portugal
| | - P Severino
- Laboratory of Nanotechnology and Nanomedicine (LNMed), University of Tiradentes (Unit), Institute of Technology and Research (ITP), Av. Murilo Dantas, 300, 49010-390 Aracaju, Brazil
| | - T Andreani
- Department of Biology and Environment, University of Trás-os-Montes e Alto Douro (UTAD), Quinta de Prados, P-5001-801 Vila Real, Portugal; Centre for Research and Technology of Agro-Environmental and Biological Sciences (CITAB), University of Trás-os-Montes e Alto Douro (UTAD), Vila Real, Portugal
| | - P Boonme
- Department of Pharmaceutical Technology, Faculty of Pharmaceutical Sciences, Prince of Songkla University, Songkhla, Thailand; Nanotec-PSU Center of Excellence on Drug Delivery System, Prince of Songkla University, Hat-Yai, Songkhla 90112, Thailand
| | - A Santini
- Department of Pharmacy, University of Napoli "Federico II", Via D. Montesano 49, 80131 Napoli, Italy
| | - A M Silva
- Department of Biology and Environment, University of Trás-os-Montes e Alto Douro (UTAD), Quinta de Prados, P-5001-801 Vila Real, Portugal; Centre for Research and Technology of Agro-Environmental and Biological Sciences (CITAB), University of Trás-os-Montes e Alto Douro (UTAD), Vila Real, Portugal
| | - E B Souto
- Department of Pharmaceutical Technology, Faculty of Pharmacy, University of Coimbra (FFUC), Pólo das Ciências da Saúde, Azinhaga de Santa Comba, 3000-548 Coimbra, Portugal; REQUIMTE/LAQV, Group of Pharmaceutical Technology, Faculty of Pharmacy, University of Coimbra, Coimbra, Portugal
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Crosara Teixeira M, Braghiroli MI, Sabbaga J, Hoff PM. Primary prevention of colorectal cancer: Myth or reality? World J Gastroenterol 2014; 20:15060-15069. [PMID: 25386054 PMCID: PMC4223239 DOI: 10.3748/wjg.v20.i41.15060] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/24/2014] [Revised: 06/21/2014] [Accepted: 07/25/2014] [Indexed: 02/06/2023] Open
Abstract
Colorectal cancer incidence has been rising strongly in parallel with economic development. In the past few decades, much has been learned about the lifestyle, dietary and medication risk factors for this malignancy. With respect to lifestyle, compelling evidence indicates that prevention of weight gain and maintenance of a reasonable level of physical activity can positively influence in lowering the risk. Although there is controversy about the role of specific nutritional factors, consideration of dietary pattern as a whole appears useful for formulating recommendations. Though quite often recommended, the role for many supplements, including omega-3, vitamin D, folate, and vitamin B6, remains unsettled. Only calcium and vitamin D supplementation appear to add a modest benefit, particularly in those with a low daily intake. With regard to chemoprevention, medications such as aspirin and nonsteroidal anti-inflammatory drugs, and postmenopausal hormonal replacement for women might be associated with substantial reductions in colorectal cancer risk, though their utility is affected by their side effect profile. However, the role of agents such as statins, bisphosphonates and antioxidants have yet to be determined. Ultimately, primary prevention strategies focusing on modifying environmental, lifestyle risk factors, and chemopreventive drugs are options that have already been tested, and may impact on colon cancer incidence.
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Crosara Teixeira M, Marques DF, Ferrari AC, Alves MFS, Alex AK, Sabbaga J, Hoff PM, Riechelmann RP. The effects of palliative chemotherapy in metastatic colorectal cancer patients with an ECOG performance status of 3 and 4. Clin Colorectal Cancer 2014; 14:52-7. [PMID: 25442812 DOI: 10.1016/j.clcc.2014.09.010] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2014] [Revised: 08/15/2014] [Accepted: 09/10/2014] [Indexed: 11/16/2022]
Abstract
BACKGROUND Although chemotherapy is standard for patients with mCRC and ECOG PS of 0/1, the real benefit for patients with ECOG PS > 2 remains uncertain, because they are generally excluded from clinical trials. Our objectives were to compare the survival and safety of ECOG PS 3/4 patients who were administered chemotherapy with those who received BSC only. PATIENTS AND METHODS We retrospectively analyzed all consecutive mCRC patients who started first-line chemotherapy at our institution in a 4-year period. A multivariable Cox regression model was used to adjust for prognostic factors and logistic regression, to identify predictive factors of Grade 3/4 toxicity. RESULTS From June 2008 to June 2012, 240 consecutive patients were included: 100 (41.7%) had an ECOG PS of 0/1, 75 (31.3%) ECOG PS of 2, and 65 (27%) ECOG PS of 3/4. Median survival for patients treated with chemotherapy was 18.4 months for patients with ECOG PS of 0/1, 10.8 months for those with ECOG PS of 2, and 6.8 months for patients with ECOG PS of 3/4. Among those with ECOG PS of 3/4, chemotherapy use led to a nonsignificant survival gain (median, 6.8 vs. 2.3 months for BSC; P = .13). Factors significantly associated with worse survival in an adjusted analysis were right-sided tumors (hazard ratio [HR], 2.97; P = .005) and ECOG PS status (ECOG PS 2 vs. 0/1; HR, 1.67; P = .025, and ECOG PS 3/4 vs. 0/1; HR, 2.67; P < .0001). The rate of Grade ≥ 3 toxicities during the first cycle did not differ significantly across ECOG groups; likely because 40% of ECOG PS 3/4 patients received upfront dose-reduced therapy. The rates of treatment-related hospitalization were similar across all ECOG groups. All deaths were disease-associated. CONCLUSION Our retrospective study suggests that chemotherapy might benefit selected mCRC patients with poor PS. With up-front dose reduction and close monitoring for toxicity, the risk of serious adverse events is minimized.
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Affiliation(s)
- Marcela Crosara Teixeira
- Disciplina de Radiologia e Oncologia, Faculdade de Medicina da Universidade de São Paulo, Instituto do Câncer do Estado de São Paulo, São Paulo, Brazil; Centro de Oncologia, Hospital Sírio Libanes, São Paulo, Brazil.
| | - Daniel Fernandes Marques
- Disciplina de Radiologia e Oncologia, Faculdade de Medicina da Universidade de São Paulo, Instituto do Câncer do Estado de São Paulo, São Paulo, Brazil; Centro de Oncologia, Hospital Sírio Libanes, São Paulo, Brazil
| | - Anezka Celis Ferrari
- Disciplina de Radiologia e Oncologia, Faculdade de Medicina da Universidade de São Paulo, Instituto do Câncer do Estado de São Paulo, São Paulo, Brazil; Centro de Oncologia, Hospital Sírio Libanes, São Paulo, Brazil
| | - Michel Fabiano Silva Alves
- Disciplina de Radiologia e Oncologia, Faculdade de Medicina da Universidade de São Paulo, Instituto do Câncer do Estado de São Paulo, São Paulo, Brazil
| | - Alexandra Khichfy Alex
- Disciplina de Radiologia e Oncologia, Faculdade de Medicina da Universidade de São Paulo, Instituto do Câncer do Estado de São Paulo, São Paulo, Brazil
| | - Jorge Sabbaga
- Disciplina de Radiologia e Oncologia, Faculdade de Medicina da Universidade de São Paulo, Instituto do Câncer do Estado de São Paulo, São Paulo, Brazil; Centro de Oncologia, Hospital Sírio Libanes, São Paulo, Brazil
| | - Paulo M Hoff
- Disciplina de Radiologia e Oncologia, Faculdade de Medicina da Universidade de São Paulo, Instituto do Câncer do Estado de São Paulo, São Paulo, Brazil; Centro de Oncologia, Hospital Sírio Libanes, São Paulo, Brazil
| | - Rachel P Riechelmann
- Disciplina de Radiologia e Oncologia, Faculdade de Medicina da Universidade de São Paulo, Instituto do Câncer do Estado de São Paulo, São Paulo, Brazil
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Remy E, Cabrito TR, Batista RA, Teixeira MC, Sá-Correia I, Duque P. The Pht1;9 and Pht1;8 transporters mediate inorganic phosphate acquisition by the Arabidopsis thaliana root during phosphorus starvation. New Phytol 2012. [PMID: 22578268 DOI: 10.1111/j.1469-8137.2012.04167] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/13/2023]
Abstract
• The activation of high-affinity root transport systems is the best-conserved strategy employed by plants to cope with low inorganic phosphate (Pi) availability, a role traditionally assigned to Pi transporters of the Pht1 family, whose respective contributions to Pi acquisition remain unclear. • To characterize the Arabidopsis thaliana Pht1;9 transporter, we combined heterologous functional expression in yeast with expression/subcellular localization studies and reverse genetics approaches in planta. Double Pht1;9/Pht1;8 silencing lines were also generated to gain insight into the role of the closest Pht1;9 homolog. • Pht1;9 encodes a functional plasma membrane-localized transporter that mediates high-affinity Pi/H⁺ symport activity in yeast and is highly induced in Pi-starved Arabidopsis roots. Null pht1;9 alleles exhibit exacerbated responses to prolonged Pi limitation and enhanced tolerance to arsenate exposure, whereas Pht1;9 overexpression induces the opposite phenotypes. Strikingly, Pht1;9/Pht1;8 silencing lines display more pronounced defects than the pht1;9 mutants. • Pi and arsenic plant content analyses confirmed a role of Pht1;9 in Pi acquisition during Pi starvation and arsenate uptake at the root-soil interface. Although not affecting plant internal Pi repartition, Pht1;9 activity influences the overall Arabidopsis Pi status. Finally, our results indicate that both the Pht1;9 and Pht1;8 transporters function in sustaining plant Pi supply on environmental Pi depletion.
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Affiliation(s)
- E Remy
- Instituto Gulbenkian de Ciência, Rua da Quinta Grande, 6, 2780-156 Oeiras, Portugal
| | - T R Cabrito
- Institute for Biotechnology and BioEngineering (IBB), Center for Biological and Chemical Engineering, Department of Bioengineering, Instituto Superior Técnico, Technical University of Lisbon, Av. Rovisco Pais, 1049-001 Lisbon, Portugal
| | - R A Batista
- Instituto Gulbenkian de Ciência, Rua da Quinta Grande, 6, 2780-156 Oeiras, Portugal
| | - M C Teixeira
- Institute for Biotechnology and BioEngineering (IBB), Center for Biological and Chemical Engineering, Department of Bioengineering, Instituto Superior Técnico, Technical University of Lisbon, Av. Rovisco Pais, 1049-001 Lisbon, Portugal
| | - I Sá-Correia
- Institute for Biotechnology and BioEngineering (IBB), Center for Biological and Chemical Engineering, Department of Bioengineering, Instituto Superior Técnico, Technical University of Lisbon, Av. Rovisco Pais, 1049-001 Lisbon, Portugal
| | - P Duque
- Instituto Gulbenkian de Ciência, Rua da Quinta Grande, 6, 2780-156 Oeiras, Portugal
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Remy E, Cabrito TR, Batista RA, Teixeira MC, Sá-Correia I, Duque P. The Pht1;9 and Pht1;8 transporters mediate inorganic phosphate acquisition by the Arabidopsis thaliana root during phosphorus starvation. New Phytol 2012; 195:356-371. [PMID: 22578268 DOI: 10.1111/j.1469-8137.2012.04167.x] [Citation(s) in RCA: 139] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/20/2023]
Abstract
• The activation of high-affinity root transport systems is the best-conserved strategy employed by plants to cope with low inorganic phosphate (Pi) availability, a role traditionally assigned to Pi transporters of the Pht1 family, whose respective contributions to Pi acquisition remain unclear. • To characterize the Arabidopsis thaliana Pht1;9 transporter, we combined heterologous functional expression in yeast with expression/subcellular localization studies and reverse genetics approaches in planta. Double Pht1;9/Pht1;8 silencing lines were also generated to gain insight into the role of the closest Pht1;9 homolog. • Pht1;9 encodes a functional plasma membrane-localized transporter that mediates high-affinity Pi/H⁺ symport activity in yeast and is highly induced in Pi-starved Arabidopsis roots. Null pht1;9 alleles exhibit exacerbated responses to prolonged Pi limitation and enhanced tolerance to arsenate exposure, whereas Pht1;9 overexpression induces the opposite phenotypes. Strikingly, Pht1;9/Pht1;8 silencing lines display more pronounced defects than the pht1;9 mutants. • Pi and arsenic plant content analyses confirmed a role of Pht1;9 in Pi acquisition during Pi starvation and arsenate uptake at the root-soil interface. Although not affecting plant internal Pi repartition, Pht1;9 activity influences the overall Arabidopsis Pi status. Finally, our results indicate that both the Pht1;9 and Pht1;8 transporters function in sustaining plant Pi supply on environmental Pi depletion.
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Affiliation(s)
- E Remy
- Instituto Gulbenkian de Ciência, Rua da Quinta Grande, 6, 2780-156 Oeiras, Portugal
| | - T R Cabrito
- Institute for Biotechnology and BioEngineering (IBB), Center for Biological and Chemical Engineering, Department of Bioengineering, Instituto Superior Técnico, Technical University of Lisbon, Av. Rovisco Pais, 1049-001 Lisbon, Portugal
| | - R A Batista
- Instituto Gulbenkian de Ciência, Rua da Quinta Grande, 6, 2780-156 Oeiras, Portugal
| | - M C Teixeira
- Institute for Biotechnology and BioEngineering (IBB), Center for Biological and Chemical Engineering, Department of Bioengineering, Instituto Superior Técnico, Technical University of Lisbon, Av. Rovisco Pais, 1049-001 Lisbon, Portugal
| | - I Sá-Correia
- Institute for Biotechnology and BioEngineering (IBB), Center for Biological and Chemical Engineering, Department of Bioengineering, Instituto Superior Técnico, Technical University of Lisbon, Av. Rovisco Pais, 1049-001 Lisbon, Portugal
| | - P Duque
- Instituto Gulbenkian de Ciência, Rua da Quinta Grande, 6, 2780-156 Oeiras, Portugal
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Monteiro PT, Dias PJ, Ropers D, Oliveira AL, Sá-Correia I, Teixeira MC, Freitas AT. Qualitative modelling and formal verification of the FLR1 gene mancozeb response in Saccharomyces cerevisiae. IET Syst Biol 2011; 5:308-16. [PMID: 22010757 DOI: 10.1049/iet-syb.2011.0001] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
BACKGROUND Qualitative models allow understanding the relation between the structure and the dynamics of gene regulatory networks. The dynamical properties of these models can be automatically analysed by means of formal verification methods, like model checking. This facilitates the model-validation process and the test of new hypotheses to reconcile model predictions with the experimental data. RESULTS The authors report in this study the qualitative modelling and simulation of the transcriptional regulatory network controlling the response of the model eukaryote Saccharomyces cerevisiae to the agricultural fungicide mancozeb. The model allowed the analysis of the regulation level and activity of the components of the gene mancozeb-induced network controlling the transcriptional activation of the FLR1 gene, which is proposed to confer multidrug resistance through its putative role as a drug eflux pump. Formal verification analysis of the network allowed us to confront model predictions with the experimental data and to assess the model robustness to parameter ordering and gene deletion. CONCLUSIONS This analysis enabled us to better understand the mechanisms regulating the FLR1 gene mancozeb response and confirmed the need of a new transcription factor for the full transcriptional activation of YAP1. The result is a computable model of the FLR1 gene response to mancozeb, permitting a quick and cost-effective test of hypotheses prior to experimental validation.
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Affiliation(s)
- P T Monteiro
- INESC-ID/IST, Rua Alves Redol 9, Lisboa 1000-029, Portugal.
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Silva AM, Cruz FLS, Lima RMF, Teixeira MC, Leão VA. Manganese and limestone interactions during mine water treatment. J Hazard Mater 2010; 181:514-520. [PMID: 20570440 DOI: 10.1016/j.jhazmat.2010.05.044] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/24/2009] [Revised: 05/08/2010] [Accepted: 05/10/2010] [Indexed: 05/29/2023]
Abstract
Manganese removal from mining-affected waters is an important challenge for the mining industry. Addressed herein is this issue in both batch and continuous conditions. Batch experiments were carried out with synthetic solutions, at 23+/-2 degrees C, initial pH 5.5 and 8.3 g limestone/L. Similarly, continuous tests were performed with a 16.5 mg/L Mn(2+) mine water, at 23 degrees C, initial pH 8.0 and 20.8 g limestone/L. Calcite limestone gave the best results and its fine grinding proved to the most effective parameter for manganese removal. In either synthetic solutions or industrial effluents, the final manganese concentration was below 1 mg/L. A change in limestone surface zeta potential is observed after manganese removal and manganese carbonate formation was suggested by IR spectroscopy. The conclusion is that limestone can remove manganese from industrial effluents for values that comply with environmental regulations.
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Affiliation(s)
- A M Silva
- Bio&Hydrometallurgy Laboratory - Universidade Federal de Ouro Preto., Campus Morro do Cruzeiro, Ouro Preto, MG, 35400-000, Brazil
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Simões T, Teixeira MC, Fernandes AR, Sá-Correia I. Adaptation of Saccharomyces cerevisiae to the herbicide 2,4-dichlorophenoxyacetic acid, mediated by Msn2p- and Msn4p-regulated genes: important role of SPI1. Appl Environ Microbiol 2003; 69:4019-28. [PMID: 12839777 PMCID: PMC165130 DOI: 10.1128/aem.69.7.4019-4028.2003] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The possible roles of 13 Msn2p- and Msn4p-regulated genes in the adaptation of Saccharomyces cerevisiae to the herbicide 2,4-D-dichlorophenoxyacetic acid (2,4-D) were examined. Single deletion of genes involved in defense against oxidizing agents (CTT1, GRX1, and GRX2/TTR1) or encoding chaperones of the HSP70 family (SSA1, SSA4, and SSE2) showed a slight effect. A more significant role was observed for the heat shock genes HSP78, HSP26, HSP104, HSP12, and HSP42, most of which encode molecular chaperones. However, the SPI1 gene, encoding a member of the glycosylphosphatidylinositol-anchored cell wall protein family, emerged as the major determinant of 2,4-D resistance. SPI1 expression reduced the loss of viability of an unadapted yeast population suddenly exposed to the herbicide, allowing earlier growth resumption. Significantly, yeast adaptation to 2,4-D involves the rapid and transient Msn2p- and Msn4p-mediated activation (fivefold) of SPI1 transcription. SPI1 mRNA levels were reduced to values slightly above those in unstressed cells when the adapted population started duplication in the presence of 2,4-D. Since SPI1 deletion leads to the higher beta-1,3-glucanase sensitivity of 2,4-D-stressed cells, it was hypothesized that adaptation may involve an Spi1p-mediated increase in the diffusional restriction of the liposoluble acid form of the herbicide across the cell envelope. Such a cell response would avoid a futile cycle due to acid reentry into the cell counteracting the active export of the anionic form, presumably through an inducible plasma membrane transporter(s). Consistent with this concept, the concentration of (14)C-labeled 2,4-D in 2,4-D-energized adapted Deltaspi1 mutant cells and the consequent intracellular acidification are higher than in wild-type cells.
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Affiliation(s)
- T Simões
- Centro de Engenharia Biológica e Química, Instituto Superior Técnico, Av. Rovisco Pais, 1049-001 Lisbon, Portugal
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Cabral MG, Viegas CA, Teixeira MC, Sá-Correia I. Toxicity of chlorinated phenoxyacetic acid herbicides in the experimental eukaryotic model Saccharomyces cerevisiae: role of pH and of growth phase and size of the yeast cell population. Chemosphere 2003; 51:47-54. [PMID: 12586155 DOI: 10.1016/s0045-6535(02)00614-8] [Citation(s) in RCA: 23] [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] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
The inhibitory effect of the herbicides 2-methyl-4-chlorophenoxyacetic acid (MCPA) and 2,4-dichlorophenoxyacetic acid (2,4-D) in Saccharomyces cerevisiae growth is strongly dependent on medium pH (range 2.5-6.5). Consistent with the concept that the toxic form is the liposoluble undissociated form, at values close to their pK(a) (3.07 and 2.73, respectively) the toxicity is high, decreasing with the increase of external pH. In addition, the toxicity of identical concentrations of the undissociated acid form is pH independent, as observed with 2,4-dichlorophenol (2,4-DCP), an intermediate of 2,4-D degradation. Consequently, at pH values above 3.5 (approximately one unit higher than 2,4-D pK(a)), 2,4-DCP becomes more toxic than the original herbicide. A dose-dependent inhibition of growth kinetics and increased duration of growth latency is observed following sudden exposure of an unadapted yeast cell population to the presence of the herbicides. This contrasts with the effect of 2,4-DCP, which essentially affects growth kinetics. Experimental evidences suggest that the acid herbicides toxicity is not exclusively dependent on the liposolubility of the toxic form, as may essentially be the case of 2,4-DCP. An unadapted yeast cell population at the early stationary-phase of growth under nutrient limitation is significantly more resistant to short-term herbicide induced death than an exponential-phase population. Consequently, the duration of growth latency is reduced, as observed with the increase of the size of the herbicide stressed population. However, these physiological parameters have no significant effect either on growth kinetics, following growth resumption under herbicide stress, or on the growth curve of yeast cells previously adapted to the herbicides, indicating that their role is exerted at the level of cell adaptation.
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Affiliation(s)
- M G Cabral
- Centro de Engenharia Biológica e Química, Instituto Superior Técnico, Av. Rovisco Pais, 1049-001, Lisboa, Portugal
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Teixeira MC, Coelho RR, Leal-Cardoso JH, Criddle DN. Comparative effects of niflumic acid and nifedipine on 5-hydroxytryptamine- and acetylcholine-induced contraction of the rat trachea. Eur J Pharmacol 2000; 394:117-22. [PMID: 10771043 DOI: 10.1016/s0014-2999(00)00089-3] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.5] [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
The effects of niflumic acid, an inhibitor of Ca(2+)-activated Cl(-) (Cl((Ca))) channels, were compared with those of the voltage-dependent Ca(2+) channel (VDCC) blocker nifedipine on 5-hydroxytryptamine (5-HT)- and acetylcholine-induced contractions of the rat isolated trachea. Niflumic acid (3-100 microM) induced a concentration-dependent inhibition of 5-HT (10 microM)-induced contractions, with a reduction to 37.0+/-9.5% of the control at the highest concentration. One micromolar nifedipine, which completely blocked 60 mM KCl-induced contractions, reduced the response to 5-HT similarly to 39.2+/-11.5% of the control. The inhibition of the 5-HT response was not significantly different from that produced by the combined presence of nifedipine (1 microM) and niflumic acid (100 microM), suggesting that their effects were not additive. In contrast, neither niflumic acid (3-100 microM) nor nifedipine (1 microM) inhibited acetylcholine-induced contractions. The contraction to 5-HT (10 microM) in Cl(-)-free solution was decreased by more than approximately 85% of the control, whilst that of acetylcholine was reduced only by approximately 36%. Our data show that niflumic acid exerts selective inhibitory effects on 5-HT-induced contraction, and suggest that activation of Cl((Ca)) channels may be a mechanism whereby 5-HT (but not acetylcholine) induces Ca(2+) entry via VDCCs to elicit contraction.
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Affiliation(s)
- M C Teixeira
- Laboratório de Eletrofisiologia, Departamento de Ciências Fisiológicas, CCS, Universidade Estadual do Ceará, Fortaleza, Brazil
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Borges AS, Machado AA, Ferreira MS, de Castro Figueiredo JF, Silva GF, Cimerman S, Bacha HA, Teixeira MC. [Concurrent leishmaniasis and human immunodeficiency virus (HIV) infection: a study of four cases]. Rev Soc Bras Med Trop 1999; 32:713-9. [PMID: 10881110] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/16/2023] Open
Abstract
Few cases of concurrent leishmaniasis and HIV infection have been reported in Brazil, despite both infections being in expansion. Two cases of visceral leishmaniasis and two cases of mucocutaneous leishmaniasis are discussed. Disseminated skin and oral lesions were found in the patients with the cutaneous form of the disease. Prolonged fever, hepatosplenomegaly and pancytopenia were the main manifestations of the visceral form. The CD4 T lymphocyte count was low in all cases. Direct examination of bone marrow aspirate for leishmania and biopsy of cutaneous lesions are the techniques of choice to confirm diagnosis. Pentavalent antimonials and amphotericin B are preferred drugs for the treatment of leishmaniasis, including patients with AIDS. The authors recommend the inclusion of this parasitosis in the differential diagnosis of opportunistic diseases in patients with AIDS.
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Affiliation(s)
- A S Borges
- Departamento de Clínica Médica, Universidade Federal de Uberlândia, Uberlândia, MG, Brasil
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Teixeira MC, Nahas WC, Mazucchi E, Ianhez LE, David-Neto E. Role of the peripheral renin profile in predicting blood pressure control after bilateral nephrectomy in renal-transplanted patients. Nephrol Dial Transplant 1998; 13:2092-7. [PMID: 9719172 DOI: 10.1093/ndt/13.8.2092] [Citation(s) in RCA: 4] [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] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
BACKGROUND The unregulated renin release by native kidneys is one of the factors responsible for the high incidence of hypertension after renal transplantation but, even after three decades of transplantation, there is still a lack of a method to identify it as the major cause of hypertension. METHODS We investigated whether or not peripheral renin activity, before and 90 min after 25 mg of captopril, can play this role. One hundred and five consecutive patients with SCr less than 2 mg/dl were studied 18 +/- 8 months after renal transplantation. Forty-seven of them were considered hypertensive and 58 normotensive. All hypertensive patients were submitted to the captopril test to analyse the peripheral renin activity profile. RESULTS In the hypertensive group, 17 patients (36%) were considered Renin-pos and 30 (64%) Renin-neg. All Renin-pos (stimulated renin = 19.1 +/- 6.4 ng/ml/h) patients were submitted to bilateral nephrectomy (bNx) and re-evaluated 6 months later. All of them normalized renin activity (4.4 +/- 3.0 ng/ml/h, P = 0.0001) and 10 of 17 (60%) became normotensive and off drugs. The remaining seven (40%) decreased the number of hypotensive drugs from 2.2 +/- 0.5 to 0.5 +/- 0.7/pt/day. There was a correlation between b-Renin and dBP (r = 0.47, P < 0.05) which was lost after bNx. An 'in situ' renal-cell carcinoma was found in two cases. Serum creatinine did not change. CONCLUSIONS This study shows that the unregulated renin-angiotensin system from the native kidneys plays a major role in the maintenance of hypertension in some patients with normal graft function and that peripheral renin activity can identify those who will benefit from bilateral nephrectomy.
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Affiliation(s)
- M C Teixeira
- Division of Urology of the Hospital das Clínicas of the University of São Paulo School of Medicine, Brazil
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Teixeira MC, Mazucchi E, Nahas WC, Ianhez LE, Machado MM, Arap S, Sabbaga E, David-Neto E. Peripheral renin activity predicts blood pressure control after bilateral nephrectomy in renal transplant patients. Transplant Proc 1997; 29:220-1. [PMID: 9122969 DOI: 10.1016/s0041-1345(96)00068-1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Affiliation(s)
- M C Teixeira
- Renal Transplantation Unit, Hospital das Clinicas, University of São Paulo, Brazil
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Teixeira MC, Alcântara-Neves NM, Sterling CR, Pontes-de-Carvalho LC, Sant'Anna OA. Incomplete dominance of the low antibody response to Cryptosporidium parvum antigens in mice selected for high and low antibody responsiveness. Braz J Med Biol Res 1996; 29:1479-83. [PMID: 9196549] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
The humoral antibody response to Cryptosporidium was investigated in mice genetically selected for high (H) and low (L) antibody responsiveness. Groups of 4-5 mice from two different selections, general primary (GP) and general secondary (GS), were studied. Following immunization with Cryptosporidium parvum antigens, the maximum levels of IgG in the HGP (X +/- SD = 1.13 +/- 0.35, N = 5) in the HGS (0.42 +/- 0.15, N = 4) lines, and of IgM in the HGP line (0.86 +/- 0.53, N = 5) were significantly higher than those in their L counterparts (0.04 +/- 0.02, N = 5; 0.05 +/- 0.02, N = 4 and 0.24 +/- 0.07, N = 5, respectively). These findings were similar to those reported for other immunogens. However, the IgG (0.22 +/- 0.05, N = 4) and the IgM (0.33 +/- 0.08, N = 4) responses to immunization of F1 (LGP x HGP) hybrids indicated an incomplete dominance of the low response, in contrast to the incomplete dominance of the high response described for many other antigens and representing an important exception. In addition, the H, L and F1 mice did not develop detectable infections when inoculated with live Cryptosporidium oocysts, supporting the view that a reduced or zero antibody production itself is not enough to permit the establishment of Cryptosporidium infection in adult mice.
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Affiliation(s)
- M C Teixeira
- Centro de Pesquisas Gonçalo Moniz, Fundação Oswaldo Cruz, Brasil
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Teixeira MC. [Promotion of mental health--new attitudes]. Servir 1996; 44:129-33. [PMID: 8718244] [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: 02/01/2023]
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Teixeira MC, David-Neto E, Sequeira DM, Mazucchi E, Machado MM, Arap S, Sabbaga E. Enhanced peripheral renin activity identifies high-renin hypertension in renal transplant patients with native kidneys. Transplant Proc 1995; 27:970-1. [PMID: 7879249] [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] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Affiliation(s)
- M C Teixeira
- Renal Transplantation Unit, Hospital das Clinicas, University of São Paulo, Brazil
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Marques-Silva VM, De Souza MH, Teixeira MC, Arcuri RA, Rumjanek VM. Myeloid leukemia differentiation by phorbol ester and retinoic acid: a practical approach. J Clin Lab Anal 1990; 4:342-9. [PMID: 2231180 DOI: 10.1002/jcla.1860040506] [Citation(s) in RCA: 8] [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] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
The effects of TPA (12-0-tetradecanoylphorbol-13-acetate) and RA (retinoic acid) were investigated on the cell lines HL60 (acute promyelocytic leukemia) and K562 (erythroleukemia) and on cells from patients with several kinds of leukemia. There were 14 cases of acute lymphocytic leukemia (ALL), 2 cases of chronic lymphocytic leukemia (CLL), 23 cases of acute myeloid leukemia (M1-M7), 5 cases of chronic myelocytic leukemia in blast crisis (CML-BC) and 2 mixed leukemias. In almost all of the cases examined, after TPA exposure cells from patients with proven myeloid leukemia became adherent to the substrate, while lymphoid leukemia cells remained in suspension, allowing the differentiation of lymphoid from myeloid blasts. The only exception was in one case of CLL, which had cells that became adherent with long filamental projections. In addition, increased phagocytosis following TPA exposure permitted characterization of M7 as this was the only myeloid leukemia negative for phagocytosis. Further discrimination between the subtypes of myeloid leukemia could be based on the increased lysozyme production seen after TPA in M4 and M5. Esterase positivity allowed the discrimination of M1 cells, which were negative before and after TPA treatment. In agreement with the results of other authors, TPA and RA led to independent ways of differentiation, granulocytic-like lineage and monocytic-like cells being favored by RA and TPA, respectively. The capacity of the same cell to differentiate into more than one lineage, depending on whether RA or TPA was used, was only seen in the present study with M3 cells.(ABSTRACT TRUNCATED AT 250 WORDS)
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MESH Headings
- Cell Transformation, Neoplastic/drug effects
- Diagnosis, Differential
- Humans
- Leukemia, Erythroblastic, Acute/diagnosis
- Leukemia, Erythroblastic, Acute/pathology
- Leukemia, Lymphocytic, Chronic, B-Cell/diagnosis
- Leukemia, Myeloid/diagnosis
- Leukemia, Myeloid/pathology
- Leukemia, Promyelocytic, Acute/diagnosis
- Leukemia, Promyelocytic, Acute/pathology
- Precursor Cell Lymphoblastic Leukemia-Lymphoma/diagnosis
- Tetradecanoylphorbol Acetate/pharmacology
- Tretinoin/pharmacology
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Affiliation(s)
- V M Marques-Silva
- Basic Research Centre, Instituto Nacional de Cancer, Rio de Janeiro, Brazil
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Abstract
Nocardia rhodochrous grown on glucose-supplemented medium produced a high yield of a glycolipid fraction (m.p. 65-70 degrees C and [alpha]25D = + 31.4 degrees), identified as 6-(C40-C46) nocardomycoloylglucose. It accounted for approx. 3.4% of the cell dry wt. and 41% of the diethyl ether soluble lipids obtained from ethanol-diethyl ether extract. Dimycoloyltrehalose (cord factor) was found in a very small amount (0.11%).
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