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Bartolomeo C, Lemes R, Morais R, Pereria G, Nunes T, Costa A, Ivanov G, Maciel R, Braconi C, Maricatto J, Janini L, Okuda L, Lee K, Prado C, Uresh R. SARS-COV-2 INFECTION AND REPLICATION KINETICS IN DIFFERENT HUMAN CELL TYPES: THE ROLE OF AUTOPHAGY, CELLULAR METABOLISM AND ACE2 EXPRESSION. Cytotherapy 2022; 24. [PMCID: PMC9595395 DOI: 10.1016/s1465-3249(22)00919-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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Moutinho-Ribeiro P, Adem B, Batista I, Silva M, Silva S, Ruivo CF, Morais R, Peixoto A, Coelho R, Costa-Moreira P, Lopes S, Vilas-Boas F, Durães C, Lopes J, Barroca H, Carneiro F, Melo SA, Macedo G. Exosomal glypican-1 discriminates pancreatic ductal adenocarcinoma from chronic pancreatitis. Dig Liver Dis 2022; 54:871-877. [PMID: 34840127 DOI: 10.1016/j.dld.2021.10.012] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/08/2021] [Revised: 10/19/2021] [Accepted: 10/27/2021] [Indexed: 12/12/2022]
Abstract
BACKGROUND AND AIMS Pancreatic ductal adenocarcinoma (PDAC) diagnosis can be difficult in a chronic pancreatitis (CP) background, especially in its mass forming presentation. We aimed to assess the accuracy of glypican-1-positive circulating exosomes (GPC1+crExos) to distinguish PDAC from CP versus the state-of-the-art CA 19-9 biomarker. METHODS This was a unicentric prospective cohort. Endoscopic ultrasound with fine-needle aspiration or biopsy and blood tests (GPC1+crExos and serum CA 19-9) were performed. RESULTS The cohort comprised 60 PDAC and 29 CP (7 of which mass forming - MF) patients. Median levels of GPC1+crExos were significantly higher in PDAC (99.7%) versus CP (28.4%; p<0.0001) with an AUROC of 0.96 with 98.3% sensitivity and 86.2% specificity for a cut-off of 45.0% (p<0.0001); this outperforms CA 19-9 AUROC of 0.82 with 78.3% sensitivity and 65.5% specificity at a cut-off of 37 U/mL (p<0.0001). The superiority of% GPC1+crExos over CA 19-99 in differentiating PDAC from CP was observed in both early (stage I) and advanced tumors (stages II-IV). CONCLUSION Levels of GPC1+crExos coupled to beads enable differential diagnosis between PDAC and CP including its mass-forming presentation.
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Magalhães L, Silveira H, Prestes S, Costa Magalhães LK, Santana RA, Ramasawmy R, Oliveira J, Roque CCR, Silva Junior RCA, Fé N, Duarte R, Maciel M, Ortiz J, Morais R, Monteiro WM, Guerra JA, Barbosa Guerra MGV. Bioecological aspects of triatomines and marsupials as wild Trypanosoma cruzi reservoirs in urban, peri-urban and rural areas in the Western Brazilian Amazon. MEDICAL AND VETERINARY ENTOMOLOGY 2021; 35:389-399. [PMID: 33394514 DOI: 10.1111/mve.12507] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/04/2020] [Revised: 12/14/2020] [Accepted: 12/15/2020] [Indexed: 06/12/2023]
Abstract
In the Amazon region, Trypanosoma cruzi transmission cycles involve a great diversity of Triatominae vectors and mammal reservoirs. Some Rhodnius spp. mainly inhabit palm trees that act as microhabitats for hosts and vectors. The current study aimed to describe aspects of the bio-ecology of the vectors and reservoirs of T. cruzi in relation to human populations resident near areas with large quantities of palm trees, in rural, peri-urban and urban collection environments, located in the Western Brazilian Amazon. Rhodnius pictipes and Didelphis marsupialis were respectively the most predominant vector and reservoir, with rates of 71% for R. pictipes and 96.5% for D. marsupialis. The vast majority of T. cruzi isolates clustered with TcI. The most prevalent haplotype was TcI COII1 (69.7%). Mauritia flexuosa and Attalea phalerata were the main ecological indicators of infestation by triatomines. Birds were the most common food source (27,71%). T. cruzi isolated from R. robustus has the haplotype HUM-13, previously detected in a chronic Chagas patient living in the same area. Our results demonstrate the relevance of this study, with the occurrence of elevated infection rates in animals, and suggest the importance of the Amazon zones where there is a risk of infection in humans.
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Rocha ML, Cunha GC, Gomes RM, Morais R, Campos L, Araujo I, Fonseca MC. P5008Empagliflozin in a real-world chronic heart failure population. Eur Heart J 2019. [DOI: 10.1093/eurheartj/ehz746.0186] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Abstract
Introduction
Heart Failure (HF) is a burdensome syndrome with significant mortality, morbidity and costs. Its prognosis is further aggravated by diabetes mellitus (DM). The EMPA-REG OUTCOME trial suggested that empagliflozin significantly reduced HF hospitalizations compared to placebo in patients with DM.
Purpose
We aimed to investigate which patients with chronic HF and DM in the outpatient setting could have been enrolled in the main empagliflozin trial.
Methods
This analysis is based on a retrospective cohort enrolling chronic HF patients who consecutively attended the HF appointment between January and July 2018. Of these, those with concomitant DM were selected and further analysed. The key EMPA-REG OUTCOME trial inclusion criteria [(i.e., hemoglobin A1c 7–10%, high cardiovascular (CV) risk and glomerular filtration rate [GFR] ≥30mL/min/1,73m2) were considered. Further, the European Medicine Agency (EMA) restriction (GFR>60mL/min/1,73m2) was also considered in an additional analysis.
Results
Of 316 patients with HF, 114 (36%) concomitantly had DM. Mean age was 74±10 years, 63% were male and most (54%) had preserved left ventricular ejection fraction. Ischemic (51%) and hypertensive (27%) HF were the most often observed etiologies. According to the inclusion criteria, 21 (18.4%) (or 5.3% when further considering the EMA restriction) HF patients could have been potentially enrolled in the main trial and derive a HF hospitalization reduction benefit from starting empagliflozin. The remainder would be excluded due to GFR<30mL/min/1.73m2 (2.6%), absence of “high CV risk” as per trial's definition (7%), HbA1c off target (18,4%) or a combination of the above criteria (53.6%). In light of the new Standards of Medical Care in Diabetes 2019, controlled patients with HbA1c off target (i.e., <7% or >10%) could be switched to a SGLT2 inhibitors, hence possibly expanding the indication to start empagliflozin to 36.8% of our HF cohort.
Figure 1
Conclusions
Roughly 1 in every 5 patients with HF and DM could have been enrolled in the main empagliflozin trial, as per key inclusion criteria, and potentially derive CV benefit from it. Thus, only a minority of our cohort shared the features for EMPA-REG OUTCOME trial inclusion, limiting the extrapolation of the trial's observed CV benefits to our HF cohort. Indeed, whether these benefits also expand to overall HF cohort is eagerly awaited by ongoing trials.
Acknowledgement/Funding
None
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Cosme F, Morais R, Peres E, Cunha J, Fraga I, Milheiro J, Filipe-Ribeiro L, Mendes J, Nunes F. Precision enology in Tawny Port wine aging process: Monitoring barrel to barrel variation in oxygen, temperature and redox potential. BIO WEB OF CONFERENCES 2019. [DOI: 10.1051/bioconf/20191502026] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Tawny Port wine is a category of the famous Portuguese fortified wine commercialized worldwide and produced in the Douro Demarcated Region. Tawny Port wine oxidative aging is a multifactorial process critical for reaching the wanted quality. Real time monitoring of important intrinsic and extrinsic factors that are known to affect both time and quality of the aging process are important to optimize and to manage the natural variability between wines aged in different long-used wood barrels. This study presents the design, development and implementation of a remote distributed system to monitor parameters that are known to be critical for Tawny Port wine aging process. Results indicate that the distributed monitoring system was capable to detect differences between oak wood barrels and between the different storage conditions. Indeed, oxygen and redox potential were the wine's parameters where the differences found between different barrels were greater under the same storage conditions. Considering that Tawny Port wine aging process is oxidative, a variation in the wine's aging process between different wood barrels is to be expected. Actually, significant differences were detected in the oxygen consumption rate amongst the different barrels. Differences in the phenolic composition was also observed in the aged wine (controlled temperature and room temperature).
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Cunha G, Gomes R, Rocha B, Silva B, Morais R, Araujo I, Fonseca C. P6633Pacing as a treatment for recurrent cardioinhibitory vasovagal syncope: systematic review with meta-analysis. Eur Heart J 2018. [DOI: 10.1093/eurheartj/ehy566.p6633] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
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Gomes R, Rocha B, Cunha G, Silva B, Morais R, Araujo I, Fonseca C, Campos L. P4736Empagliflozin targeting the real-world heart failure population. Eur Heart J 2018. [DOI: 10.1093/eurheartj/ehy563.p4736] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
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Albuquerque A, Pessegueiro Miranda H, Lopes J, Gandara J, Rodrigues S, Gaspar R, Morais R, Ramalho R, Rodrigues-Pinto E, Cardoso H, Barroca H, Dias CC, Carneiro F, Macedo G. Liver transplant recipients have a higher prevalence of anal squamous intraepithelial lesions. Br J Cancer 2017; 117:1761-1767. [PMID: 29093575 PMCID: PMC5729480 DOI: 10.1038/bjc.2017.370] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2017] [Revised: 09/26/2017] [Accepted: 09/29/2017] [Indexed: 12/17/2022] Open
Abstract
Background: Anal squamous intraepithelial lesions (ASIL) are precancerous lesions of anal squamous cell carcinoma, with a higher prevalence in immunosuppressed patients. There are some studies in kidney transplant recipients, but there is no information regarding prevalence in liver transplantation. Our aim was to evaluate the prevalence of ASIL in this setting. Methods: Prospective case–control study involving liver transplant recipients without any other known risk factor for ASIL (n=59), which were compared with a healthy control group (n=57). All were submitted to anal cytology and high-resolution anoscopy was performed in those with abnormal results. Results: Ten (17%) of liver transplant recipients had abnormal cytological results, seven patients had atypical squamous cells of undetermined significance (ASC-US), one patient had atypical squamous cells that cannot exclude high-grade (ASC-H) and two patients had high-grade squamous intraepithelial lesions (HSIL). In the control group, one patient (2%) had an ASC-US result (P=0.005). Anal squamous intraepithelial lesions were confirmed in 7 out of 10 of liver transplant patients and 0 out of 1 in the controls (P=0.013) by high-resolution anoscopy with biopsies. Current smoking was the only risk factor for abnormal cytology (odds ratio=5.87, 95% confidence intervals=1.22–28.12, P=0.027). Conclusions: Liver transplant patients have a higher risk of ASIL. Screening should be considered, especially in smokers.
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Pinto-Lopes P, Carneiro-Leão L, Morais R, Pinheiro J, Vieira Lopes A, Bettencourt P. Acute heart failure and rhabdomyolysis: a clue for the diagnosis of polymyositis with cardiac involvement. Reumatismo 2017; 69:78-83. [PMID: 28776362 DOI: 10.4081/reumatismo.2017.924] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2016] [Revised: 02/08/2017] [Accepted: 04/27/2017] [Indexed: 11/23/2022] Open
Abstract
Polymyositis is an idiopathic inflammatory myopathy, characterized by proximal muscle weakness and sometimes extramuscular manifestations. We report the case of a 51-year-old male, with history of complete heart block, which required pacemaker implantation, and subsequently heart failure, presenting to the emergency department with worsening of dyspnea and peripheral edema. He was admitted to the Internal Medicine ward with acute heart failure and started on diuretic therapy. During hospitalization, he was discovered to have marked rhabdomyolysis. Examination revealed proximal symmetrical muscle weakness and arthralgia. The immunological study, electromyography and muscle biopsy confirmed polymyositis. The patient was started on prednisolone with clinical improvement and resolution of rhabdomyolysis. The presence of conduction defect, ventricular dysfunction, mitral valve regurgitation, segmental hypokinesia (myocardial scintigraphy without perfusion defects) and pulmonary hypertension, as well as elevated troponin with improvement after specific therapy, points to cardiac involvement. Polymyositis is a rare entity, with an insidious evolution and a myriad of extramuscular features that can mimic other conditions. In particular, cardiac involvement may be the first and only recognized manifestation. The key point for the diagnosis is to contemplate the possibility of polymyositis.
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Albuquerque RS, Morais R, Reis AN, Miranda MS, Dias EAR, Monteiro FM, Paz CCP, Nichi M, Kawai GKV, Della'Aqua CPF, Papa FO, Viana RB, Gimenes LU. Comparison of two methods of seminal plasma removal on buffalo (Bubalus bubalis) sperm cryopreservation. Reprod Domest Anim 2017; 52:905-910. [DOI: 10.1111/rda.12992] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2017] [Accepted: 04/04/2017] [Indexed: 11/27/2022]
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Silva N, Santos P, Ferreira J, Santos M, Reis M, Morais R. Multi-purpose and Multi-source Energy Management System for Biomedical Implants. ACTA ACUST UNITED AC 2012. [DOI: 10.1016/j.proeng.2012.09.249] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Morais R, Silva N, Santos P, Frias C, Ferreira J, Ramos A, Simõesd J, Baptista J, Reis M. Permanent magnet vibration power generator as an embedded mechanism for smart hip prosthesis. ACTA ACUST UNITED AC 2010. [DOI: 10.1016/j.proeng.2010.09.221] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Vorreau P, Sygletos S, Parmigiani F, Hillerkuss D, Bonk R, Petropoulos P, Richardson DJ, Zarris G, Simeonidou D, Klonidis D, Tomkos I, Weerasuriya R, Ibrahim S, Ellis AD, Cotter D, Morais R, Monteiro P, Ben Ezra S, Tsadka S, Freude W, Leuthold J. Optical grooming switch with regenerative functionality for transparent interconnection of networks. OPTICS EXPRESS 2009; 17:15173-15185. [PMID: 19687996 DOI: 10.1364/oe.17.015173] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
We demonstrate a regenerative optical grooming switch for buffer-less interconnection of metro/access and metro/core ring networks with switching functionality in time, space and wavelength domain. Key functionalities of the router are the traffic aggregation with time-slot interchanging (TSI) functionality, the WDM-to-ODTM multiplexing and the OTDM-to-WDM demultiplexing of high-speed channel into lower bit-rate tributaries as well as multi-wavelength all-optical 2R regeneration of several higher-speed signals. BER and Q-factor measurements of different switching scenarios show excellent performance with no error floor and Q-factors above 21 dB.
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Neves M, Ferreira M, Terreaux C, Hostettmann K, Morais R. Phytochemical profiles of Targionia lorbeeriana: grown in vitro and in the open. Z NATURFORSCH C 2001; 56:726-30. [PMID: 11724376 DOI: 10.1515/znc-2001-9-1010] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
The terpenoid constituents of Targionia lorbeeriana grown in vivo and in vitro were compared. The analysis of the dichloromethane extract was performed by HPLC-UV and by HPLC-MS. The obtained results revealed that the sesquiterpene lactones isolated from the dichloromethane extract of the wild Targionia lorbeeriana were also produced by the liverwort in in vitro cultures, in the same relative amounts. The composition of essential oils was evaluated by GC and GC-MS. Both, the yield and diversity of the essential oil obtained from wild growing T. lorbeeriana gametophytes were higher than those growing in vitro. Although, a significant number of compounds produced in vivo were maintained in vitro, a considerable number of other ones were not detected. Instead, under in vitro conditions, some new compounds were found which do not accumulate under wild conditions.
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Orset S, Leach GC, Morais R, Young AJ. Spray-drying of the microalga Dunaliella salina: effects on beta-carotene content and isomer composition. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 1999; 47:4782-4790. [PMID: 10552890 DOI: 10.1021/jf990571e] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
The effects of spray-drying of the unicellular microalga Dunaliella salina on its beta-carotene content and geometric isomer composition have been studied. The efficacy of a range of synthetic and natural antioxidants in preventing degradation of beta-carotene has been determined. Losses of beta-carotene and isomerization were minimal during processing for both the control (no exogenous antioxidants) and the samples containing butylated hydroxytoluene (BHT) and tert-butylhydroquinone (TBHQ). However, the use of tocopherol-based antioxidants resulted in degradation of 52-72% of beta-carotene during the drying process. All dried powders of Dunaliella proved to be unstable during storage in the presence of light and air, with beta-carotene degraded according to a first-order kinetic model. Of the antioxidants studied, only TBHQ was successful in significantly minimizing degradation (degradation constants of 0.03 and 0.04 days(-)(1), compared to 0.53 days(-)(1) for the respective control). For control powders and those with BHT added to the feed, the degradation constants were reduced to values between 0.27 and 0.37 days(-)(1) by restricting light and flushing with nitrogen; however, storage in the dark alone had no effect. For more slowly degrading powders having TBHQ added to the feed, it was clear that degradation of beta-carotene was influenced by both light and oxygen. During storage the 9-cis isomer of beta-carotene was significantly more unstable than the all-trans form. TBHQ was, however, successful in reducing relative losses of this isomer for samples stored in the dark. The results suggest a dominant photodegradative mechanism for the loss of the 9-cis isomer of beta-carotene.
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Leach G, Oliveira G, Morais R. Spray-drying of Dunaliella salina to produce a ? -carotene rich powder. J Ind Microbiol Biotechnol 1998. [DOI: 10.1038/sj.jim.2900485] [Citation(s) in RCA: 64] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Neves M, Morais R, Gafner S, Hostettmann K. Three triterpenoids and one flavonoid from the liverwort Asterella blumeana grown in vitro. Phytother Res 1998. [DOI: 10.1002/(sici)1099-1573(1998)12:1+3.0.co;2-1] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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Wang H, Meury L, Morais R. Cloning and characterization of cDNAs encoding chicken mitogen-activated protein kinase kinase type 2, MEK2: downregulation of MEK2 in response to inhibition of mitochondrial DNA expression. Biochemistry 1997; 36:15371-80. [PMID: 9398267 DOI: 10.1021/bi971946x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
The present work was initiated with the aim of identifying nuclear genes whose expression is sensitive to the mitochondrial DNA (mtDNA) status of transformed chicken DU24 cells. We cloned and sequenced cDNAs for the mitogen-activated protein kinase kinase type 2, MEK2, a protein involved in the mitogenic growth factor signal transduction pathway in vertebrates. Sequence comparisons between the chicken protein and its mammalian counterparts indicated that MEK2 proteins are highly conserved among vertebrates. Southern blot analysis of endonuclease-digested genomic DNA from primary chick embryo fibroblasts (CEF) suggested that MEK2 is a single-copy gene in this vertebrate species. The steady-state level of MEK2 transcripts is decreased in DUS3 mtDNA-less (rho0) cells developed by long-term exposure of DU24 rho+ cells to ethidium bromide (EtdBr). Run-on in vitro transcription assays and mRNA stability studies indicated that the decrease in MEK2 mRNA content is associated with post-transcriptional regulation. In parental DU24 cells, MEK2 mRNA content decreased after inhibition of mtDNA transcription by EtdBr and inhibition of translation on mitoribosomes by chloramphenicol (CAM). Cytoplasmic hybrids (cybrids) constructed by fusion of chicken rho0 cells with enucleated parental cells and CEF recovered a basal level of MEK2 expression. The MEK2 protein content is decreased in DUS3 rho0 cells and in parental DU24 rho+ cells treated with EtdBr and CAM for 6 days, while that of MEK1, a closely related kinase, remained unchanged. On the basis of these observations, we propose that mitochondria participate in the mitogenic signal transduction pathway in chicken cells through regulation of MEK2 expression.
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Blais C, Drapeau G, Meloche S, Morais R, Adam A. Digoxigenin-labeled peptides for the immunological quantification of intracellular signaling proteins: application to the MAP kinase kinase isoform MEK2. Biotechniques 1997; 23:1098-103. [PMID: 9421643 DOI: 10.2144/97236rr01] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
Two competitive enzyme immunoassays using digoxigenin-labeled peptides have been developed for the quantification of the protein kinase MEK2 in cell extracts. Rabbit polyclonal antibodies directed against either the amino-terminal or proline-rich amino acid sequences of MEK2 were used for the immunoconcentration of the protein. Anti-digoxigenin Fab fragments labeled with horseradish peroxidase allowed the detection of the immune complexes. Amino-terminal and proline-rich enzyme immunoassays exhibited a sensitivity level of 63 and 71 fmol/mL, respectively, and displayed a half-maximal saturation value of 1320 and 1780 fmol/mL. The intra- and inter-assay coefficients of variation for both assays assessed at three different concentrations of MEK2 were lower than 6% and 12%, respectively. The amount of MEK2 measured by the two methods demonstrated an excellent correlation with the expression level of the protein detected by immunoblot analyses when tested on different cell lysates.
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Wang H, Morais R. Up-regulation of nuclear genes in response to inhibition of mitochondrial DNA expression in chicken cells. BIOCHIMICA ET BIOPHYSICA ACTA 1997; 1352:325-34. [PMID: 9224956 DOI: 10.1016/s0167-4781(97)00035-3] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Vertebrate cells depleted of (rho0) mitochondrial DNA (mtDNA) exhibited phenotypic traits that differed from the parental (rho+) cells. To isolate genes whose expression is associated with mtDNA depletion, we constructed cDNA libraries from mRNAs isolated from chicken rho+ cells transformed by the MC29 (v-myc-containing) retrovirus and from rho0 cells developed by long-term exposure of the rho+ cells to ethidium bromide (EtdBr). Through subtractive hybridization procedures, three genes, elongation factor 1 alpha (EF- 1 alpha), beta-actin and v-myc were identified and found to be up-regulated in rho0 cells. In addition, Northern analysis demonstrated that the mRNA content for GAPDH was also elevated in rho0 cells. Run-on transcription assays and mRNA stability studies in the presence of actinomycin D indicated that elevated expression of these four genes depends, at least in part, upon increased rate of transcription. Other regulatory mechanisms contribute to the elevated expression of the transcripts in rho0 cells, as suggested by cycloheximide enhancement of the accumulation of the mRNAs for EF-1 alpha and beta-actin in rho0 cells, but not in parental rho+ cells. Moreover, inhibition of mtDNA replication and transcription by EtdBr and inhibition of translation on mitoribosomes by chloramphenicol also increased the expression of the four genes in parental rho+ cells, thus mimicking the situation in rho0 cells. These data suggest that information encoded within mtDNA participates in the regulation of nuclear genes in chicken cells.
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Raymond P, Blais C, Décarie A, Morais R, Adam A. Zidovudine potentiates local and systemic inflammatory responses in the rat. JOURNAL OF ACQUIRED IMMUNE DEFICIENCY SYNDROMES AND HUMAN RETROVIROLOGY : OFFICIAL PUBLICATION OF THE INTERNATIONAL RETROVIROLOGY ASSOCIATION 1997; 14:399-407. [PMID: 9170413 DOI: 10.1097/00042560-199704150-00002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
The effect of chronic treatment with zidovudine (AZT) on the inflammatory response was examined in the rat. AZT was administered orally for 36 days. On day 35, inflammation was induced by hindpaw injection of 1% carrageenan lambda. Paw edema over a 24-hour period was used as a marker of the local inflammatory reaction. On day 36, quantification of immunoreactive T-kininogen and alpha 1-inhibitor-3 in liver and serum was used to assess the systemic inflammatory response. Albumin was selected as a protein whose concentration is modified only slightly or not at all during the acute-phase response. Animals treated with AZT transiently exhibited significantly greater (18%) paw edema 3 hours after carrageenan injection. AZT treatment alone induced a 1.8-fold increase in serum T-kininogen concentration, but it had no effect on albumin and alpha 1-inhibitor-3. In rats with inflamed paws, AZT administration led to a significant increase in liver (3.4-fold) and serum (1.8-fold) immunoreactive T-kininogen content. Dot blot analysis of total RNA isolated from liver correlated with the protein measurements. Our results indicate that chronic treatment with AZT potentiates the nonspecific local and the systemic inflammatory responses in the rat.
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Coppey-Moisan M, Brunet AC, Morais R, Coppey J. Dynamical change of mitochondrial DNA induced in the living cell by perturbing the electrochemical gradient. Biophys J 1996; 71:2319-28. [PMID: 8913573 PMCID: PMC1233722 DOI: 10.1016/s0006-3495(96)79472-9] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
Digital-imaging microscopy was used in conditions that allowed the native state to be preserved and hence fluorescence variations of specific probes to be followed in the real time of living mammalian cells. Ethidium bromide was shown to enter into living cells and to intercalate stably into mitochondrial DNA (mtDNA), giving rise to high fluorescence. When the membrane potential or the pH gradient across the inner membrane was abolished by specific inhibitors or ionophores, the ethidium fluorescence disappeared from all mtDNA molecules within 2 min. After removal of the inhibitors or ionophores, ethidium fluorescence rapidly reappeared in mitochondria, together with the membrane potential. The fluorescence extinction did not result from an equilibrium shift caused by leakage of free ethidium out of mitochondria when the membrane potential was abolished but was most likely due to a dynamical mtDNA change that exposed intercalated ethidium to quencher, either by weakening the ethidium binding constant or by giving access of a proton acceptor (such as water) to the interior of mtDNA. Double labeling with ethidium and with a minor groove probe (4',6-diamino-2-phenylindole) indicated that mtDNA maintains a double-stranded structure. The two double-stranded DNA states, revealed by the fluorescence of mitochondrial ethidium, enhanced or quenched in the presence of ethidium, seem to coexist in mitochondria of unperturbed fibroblast cells, suggesting a spontaneous dynamical change of mtDNA molecules. Therefore, the ethidium fluorescence variation allows changes of DNA to be followed, a property that has to be taken into consideration when using this intercalator for in vivo as well as in vitro imaging studies.
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Raymond P, Wang H, Blais C, Décarie A, Adam A, Morais R. Chloramphenicol and the inflammatory response in the rat. Upregulation of the gene for T2-kininogen in liver. J Pharmacol Exp Ther 1996; 278:934-40. [PMID: 8768750] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
Recent observations have indicated that cytokine and glucocorticoid mediators of the inflammatory response in mammals interfere with mitochondrial respiratory capacity of cultured cells. Here, we report studies on the effect of the antibiotic chloramphenicol (CAP), a potent mitochondrial protein synthesis and respiratory inhibitor, on the inflammatory response in the rat. CAP was injected daily (i.p.) at doses of 30, 100 and 300 mg kg-1 during a period of 10 days. Acute inflammation was induced on day 10 by s.c. injection of carrageenan into the hindpaws. Paw edema reaction and liver and serum expression of the acute phase protein T-kininogen were used as markers of the local and systemic inflammatory response, respectively. Albumin was selected as a liver protein whose expression is little or not affected in inflamed rats. We found that the swelling process induced locally by carrageenan injection was significantly altered in rats treated with CAP at the dose level of 300 mg kg-1. The inhibitory effect of CAP was transient, extending up to 3 hr after carrageenan injection. CAP was observed also to alter the mitochondrial respiratory capacity of liver cells, reducing cytochrome C oxidase activity up to 50%. In contrast, liver immunoreactive T-kininogen content and the T2-kininogen mRNA steady-state level were found to increase in a dose-related manner in CAP-treated animals. These values were slightly different from those recorded in control rats inflamed with carrageenan. No significant increase of T-kininogen serum content was seen at all dose levels of CAP injected. Among inflamed animals, those exposed long-term to CAP had elevated liver and serum T-kininogen content and t2-kininogen mRNA steady-state levels. Expression of the gene for albumin was not affected in rats treated or not with CAP. The present observations indicate that CAP influences both local and systemic inflammatory responses in the rat.
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Raymond P, Bouvier M, Drapeau G, Blais C, Morais R, Adam A. Bradykinin decreases T-kininogen synthesis in a rat hepatoma cell line: evidence of bradykinin B2-type receptors. Peptides 1996; 17:1171-6. [PMID: 8959752 DOI: 10.1016/s0196-9781(96)00180-5] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Using the rat H4-II-E-C3 hepatoma cell line, we investigated the presence of [125I][Tyr8]BK binding sites and the direct modulation of T-kininogen synthesis, an acute phase protein of inflammation, by bradykinin (BK) analogues. H4-II-E-C3 membrane preparations exhibited [125I][Tyr8]BK binding sites with a Kd of 4 nM and a Bmax of 120 fmol/mg of protein. Des-Arg9-BK showed no affinity (Ki > 10(-4) M) for these sites. The B2 metabolism-resistant and selective agonist [Phe8 psi (CH2-NH)Arg9]BK decreased the T-kininogen concentration in H4-II-E-C3 medium by 23% (p < 0.05). This effect was reversed by coincubation with the B2 antagonist HOE140. The B1 agonist Sar[D-Phe8]des-Arg9-BK and the B1 antagonist Lys[Leu8]des-Arg9-BK did not modify T-kininogen concentrations. The interaction between cytokines and kinins in the modulation of T-kininogen synthesis was also studied. Preincubation of hepatoma cells for 1 h with interleukin-1 alpha (IL-1 alpha) alone reduced T-kininogen concentrations by 37%, and this effect was blocked by co-addition of HOE140. Preincubation with interleukin-6 (IL-6) increased T-kininogen levels by threefold. Coincubation in the presence of the B2 agonist decreased this augmentation by 24%. The latter effect was reversed by co-addition of HOE140. None of the cytokines tested induced a response to the B1 agonist or antagonist under the experimental conditions studied. Overall, these results support the presence of a functional B2 receptor on H4-II-E-C3 cells that modulates T-kininogen synthesis. We suggest that the receptor is involved in vivo in a retroaction loop between kinins and T-kininogen production during inflammation. We speculate that BK could be a mediator in the modulation of acute phase protein synthesis by the cytokines IL-1 alpha and IL-6.
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