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Simões P, Silva A, Pereira F, Marques E, Grade S, Milhazes N, Borges F, Ribeiro C, Macedo T. Methamphetamine induces alterations on hippocampal NMDA and AMPA receptor subunit levels and impairs spatial working memory. Neuroscience 2007; 150:433-41. [DOI: 10.1016/j.neuroscience.2007.09.044] [Citation(s) in RCA: 83] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2007] [Revised: 08/28/2007] [Accepted: 09/11/2007] [Indexed: 11/27/2022]
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Palma AC, Araújo F, Duque V, Borges F, Paixão MT, Camacho R. Molecular epidemiology and prevalence of drug resistance-associated mutations in newly diagnosed HIV-1 patients in Portugal. INFECTION GENETICS AND EVOLUTION 2007; 7:391-8. [PMID: 17360244 DOI: 10.1016/j.meegid.2007.01.009] [Citation(s) in RCA: 61] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/31/2006] [Revised: 01/25/2007] [Accepted: 01/30/2007] [Indexed: 11/18/2022]
Abstract
BACKGROUND Drug resistance transmission in newly diagnosed, drug-naïve HIV-1 infected individuals has been previously reported, with rates ranging from 5 to 27%. The aim of this study is to investigate the prevalence of resistance-associated mutations in drug-naïve, newly diagnosed patients, as well as monitoring the diversity of HIV-1 strains circulating in Portugal. METHODS One hundred eighty samples from newly diagnosed patients were prospectively collected during 2003, according to the distribution of HIV-1 infections in Portugal. Epidemiological, clinical and laboratory data was collected using a standardized form. Population sequencing was performed using an automated sequencer (ABI Prism 3100, Applied Biosystems) and a commercially available assay (ViroSeq HIV-1 Genotyping System, v2.0, Abbott). Stanford HIV Sequence Database was used for interpretation of resistance data; subtyping was performed using the REGA Subtyping Tool. When subtype was unassigned, further analysis was done using an alignment with reference sequences, and phylogenetic tools like Simplot and PHYLIP. Mutations listed by the International AIDS Society-USA were considered, except E44D and V118I. RESULTS Patient population included 124 males (69%) and 56 females (31%), the median age being 35. Western Europe was the main region of origin (77.2%), followed by Africa (18.3%), South America (2.8%) and Asia (1.1%). The most common route of transmission was heterosexual contact (54.4%), followed by intravenous drug use (20%), homo/bisexual individuals (19.4%) and blood transfusion (0.6%). The commonest subtypes were B (41.7%) and G (29.4%), while other non-B subtypes rated 12.8% and recombinant forms represented 16.1% of the samples. Fourteen patients (7.78%) were identified as carrying resistance-associated mutations. Ten were resistant to drugs from one class, three to drugs from two classes and one to drugs from all three classes. No statistically significant associations were found between age, gender, route of transmission, subtype and resistance. CONCLUSIONS The identification of newly diagnosed individuals carrying resistance-associated mutations confirms that drug resistance transmission is a public health problem in Portugal, with a possible impact on prevention, treatment and monitoring of HIV-1 infections.
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Moreno CRC, Louzada FM, Teixeira LR, Borges F, Lorenzi-Filho G. Short sleep is associated with obesity among truck drivers. Chronobiol Int 2007; 23:1295-303. [PMID: 17190714 DOI: 10.1080/07420520601089521] [Citation(s) in RCA: 70] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Recent studies suggest that short-sleep duration is independently associated with obesity in the general population. The population of truck drivers is of particular interest, because they frequently work irregular shifts that in turn are associated with short-sleep duration. In addition, truck drivers have a high prevalence of sedentary habits, poor diet, and obesity. The present study aimed at verifying the association between sleep patterns and factors associated with obesity in this population. The study sample consisted in 4,878 truck drivers who participated in a campaign promoted by a highway company in the State of São Paulo, Brazil. This campaign offered highway truck drivers a medical and laboratorial evaluation. The truck drivers completed a questionnaire concerning demographic data, sleep duration, consumption of medications, and medical problems, such as diabetes, cardiopathy, and hypertension; as well as the Berlin questionnaire, which is able to discriminate low and high risk for obstructive sleep apnea. Blood samples were collected to measure glucose and cholesterol levels. Also, body weight and height were registered to calculate the body mass index (BMI). The mean age (+/-SD) of the truck drivers studied was 40+/-10 years. Out of the truck drivers analyzed, 28.3% (n = 1,379) had a BMI > or =30.0 Kg/m2 (obesity). Among the 4,878 drivers included in the study, 1,199 (24.6%) were on medications and 334 (6.8%) were diabetic. Drivers (26.9%) with the greater BMI had a short sleep length. The independent factors associated with obesity were sleep duration <8 h/day (OR = 1.24), age >40 years (OR = 1.20), glucose levels >200 (OR = 2.02), cholesterol levels >240 (OR = 1.57), snoring (OR = 1.74), and hypertension (OR = 2.14). Smoking was not associated with obesity (OR = 0.69), and diabetes was considered a control variable. In conclusion, this study supports the hypothesis that short sleep duration as well as age >40 years are independently associated with obesity. This particular combination (short-sleep duration and obesity) is independently associated with several healthcare problems, including high levels of cholesterol, glucose, snoring, and hypertension. However, due to the cross-sectional nature of this study, no cause-effect relationship can be drawn from these results.
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Petersenn S, Borges F, Bouterfa H, Chang TC, Chevrin A, Farrall A, Mercado M, Patocs A, Podoba J, Safari M. An open-label, prospective, multicenter study in patients with acromegaly to assess the safety, efficacy, and tolerability of octreotide LAR as primary therapy. Exp Clin Endocrinol Diabetes 2006. [DOI: 10.1055/s-2006-954698] [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: 10/19/2022]
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Andrade LCR, Paixão JA, de Almeida MJM, Siquet C, Borges F. 2,2,4,4-Tetra- tert-butyl-1,3,5,2,4-benzotrioxadisilepine-7-carbaldehyde. Acta Crystallogr C 2006; 62:o95-7. [PMID: 16456297 DOI: 10.1107/s0108270105043052] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2005] [Accepted: 12/22/2005] [Indexed: 05/06/2023] Open
Abstract
The molecule of the title compound, C23H40O4Si2, features an approximate non-crystallographic C2 symmetry axis. The aldehyde group is disordered over two positions with similar occupancies. The geometry of the isolated molecule was studied by ab initio quantum mechanical calculations employing a molecular orbital Hartree-Fock method. The calculations reproduce well the equilibrium geometry but slightly overestimate the value of the Si-O bond lengths of the trioxadisilepine ring.
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Sousa J, Calheiros R, Rio V, Borges F, Marques M. Conformational analysis of the potential anticancer agent ethyl trihydroxycinnamate—A combined raman spectroscopy and ab initio study. J Mol Struct 2006. [DOI: 10.1016/j.molstruc.2005.09.004] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
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Fresco P, Borges F, Diniz C, Marques MPM. New insights on the anticancer properties of dietary polyphenols. Med Res Rev 2006; 26:747-66. [PMID: 16710860 DOI: 10.1002/med.20060] [Citation(s) in RCA: 333] [Impact Index Per Article: 18.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Cancer, one of the major causes of death across the world, has shown to be a largely preventable disease, highly susceptible to modulation by dietary factors. Phenolic compounds, abundant in vegetables and fruits ubiquitous in diet, were described to play an important role as chemopreventive agents. Since conventional therapeutic and surgical approaches have not been able to control the incidence of most cancer types, the development of chemopreventive strategies is an urgent priority in public health. The current diet phenolic intake is often insufficient to protect from mutagens (either exogenous or endogenous), which leads to the need for dietary supplementation as an alternative approach. Research efforts are placing increasing emphasis on identifying the biological mechanisms and in particular the signal transduction pathways related to the chemopreventive activities of these compounds. These effects are believed to occur by the regulation of signaling pathways such as nuclear factor-kappaB (NF-kappaB), activator protein-1 (AP-1) or mitogen-activated protein kinases (MAPK). Dietary polyphenols can exert their effects on these pathways separately or sequentially and in addition the occurrence of crosstalk between these pathways cannot be overlooked. By modulating cell signaling pathways, polyphenols activate cell death signals and induce apoptosis in precancerous or malignant cells resulting in the inhibition of cancer development or progression. However, regulation of cell signaling pathways by dietary polyphenols can also lead to cell proliferation/survival or inflammatory responses due to increased expression of several genes. The present review summarizes the most recent advances providing new insights into the molecular mechanisms underlying the promising anticarcinogenic activity of dietary polyphenols.
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Borges F, Roleira F, Milhazes N, Santana L, Uriarte E. Simple coumarins and analogues in medicinal chemistry: occurrence, synthesis and biological activity. Curr Med Chem 2005; 12:887-916. [PMID: 15853704 DOI: 10.2174/0929867053507315] [Citation(s) in RCA: 662] [Impact Index Per Article: 34.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Coumarins, also known as benzopyrones, are present in remarkable amounts in plants, although their presence has also been detected in microorganisms and animal sources. The structural diversity found in this family of compounds led to the division into different categories, from simple coumarins to many other kinds of policyclic coumarins, such as furocoumarins and pyranocoumarins. Simple coumarins and analogues are a large class of compounds that have attracted their interest for a long time due to their biological activities: they have shown to be useful as antitumoural, anti-HIV agents and as CNS-active compounds. Furthermore, they have been reported to have multiple biological activities (anticoagulant, anti-inflammatory), although all these properties have not been evaluated systematically. In addition, their enzyme inhibition properties, antimicrobial and antioxidant activities are other foremost topics of this field of research. The present work is to survey the information published or abstracted from 1990 till 2003, which is mainly related to the occurrence, synthesis and biological importance of simple coumarins and some analogues, such as biscoumarins and triscoumarins. Data are also highlighted, concerning the development of new synthetic strategies that could help in drug design and in the work on SAR or QSAR.
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Santana L, Uriarte E, Roleira F, Milhazes N, Borges F. Furocoumarins in medicinal chemistry. Synthesis, natural occurrence and biological activity. Curr Med Chem 2005; 11:3239-61. [PMID: 15579011 DOI: 10.2174/0929867043363721] [Citation(s) in RCA: 168] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The scope of this review encompasses the importance of furocoumarins and the most important developments in this field that have been made in recent years, with particular emphasis placed on the aspects related to medicinal chemistry. A concise and exhaustive overview is given regarding the methods used for the synthesis of these compounds, new furocoumarins isolated from natural sources, and the most significant biological properties associated with these molecules. The section describing the synthetic methods is organized on the basis of the key step used for the formation of the two different oxygenated rings. In this respect there are three possibilities: (i) formation of the furan ring onto the coumarin, (ii) formation of the pyrone ring onto the benzofuran and (iii) the simultaneous formation of both oxygenated rings onto a benzene unit. The most recent preparative approaches are discussed along with modifications or improvements to methods that, though not particularly new, are still commonly used. The recently discovered natural furocoumarins are focused and presented in tables that provide information about its structure and source. The discussion of the biological importance of furocoumarins mainly focuses on their more relevant applications in photochemotherapy, but also provides examples of their versatility in a range of applications in the fields of biology and pharmacology.
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Fiuza SM, Gomes C, Teixeira LJ, Girão da Cruz MT, Cordeiro MNDS, Milhazes N, Borges F, Marques MPM. Phenolic acid derivatives with potential anticancer properties--a structure-activity relationship study. Part 1: methyl, propyl and octyl esters of caffeic and gallic acids. Bioorg Med Chem 2005; 12:3581-9. [PMID: 15186842 DOI: 10.1016/j.bmc.2004.04.026] [Citation(s) in RCA: 207] [Impact Index Per Article: 10.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2004] [Accepted: 04/19/2004] [Indexed: 11/25/2022]
Abstract
The antiproliferative and cytotoxic properties of polyphenolic acid derivatives, structurally related with the natural models caffeic and gallic acids, have been tested in human cervix adenocarcinoma cells (HeLa). Simultaneous structural information was obtained for these compounds through theoretical ab initio methods. This study was conducted for the following esters: methyl caffeate (MC, 1), propyl caffeate (PC, 2), octyl caffeate (OC, 3), methyl gallate (MG, 4), propyl gallate (PG, 5) and octyl gallate (OG, 6). A significant growth-inhibition effect was assessed for some of these compounds, clearly dependent on their structural characteristics. Marked structure-activity relationships (SARs)--namely the number of hydroxyl ring substituents--were found to rule the biological effect of such systems.
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Garrido J, Delerue-Matos C, Borges F, Macedo T, Oliveira-Brett A. Voltammetric Oxidation of Drugs of Abuse III. Heroin and Metabolites. ELECTROANAL 2004. [DOI: 10.1002/elan.200302975] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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Garrido J, Delerue-Matos C, Borges F, Macedo T, Oliveira-Brett A. Voltammetric Oxidation of Drugs of Abuse I. Morphine and Metabolites. ELECTROANAL 2004. [DOI: 10.1002/elan.200302966] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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Garrido J, Delerue-Matos C, Borges F, Macedo T, Oliveira-Brett A. Voltammetric Oxidation of Drugs of Abuse II. Codeine and Metabolites. ELECTROANAL 2004. [DOI: 10.1002/elan.200302967] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Fiuza S, Van Besien E, Milhazes N, Borges F, Marques M. Conformational analysis of a trihydroxylated derivative of cinnamic acid—a combined Raman spectroscopy and Ab initio study. J Mol Struct 2004. [DOI: 10.1016/j.molstruc.2004.02.019] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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Calheiros R, Milhazes N, Borges F, Marques M. β-Nitrostyrene derivatives—a conformational study by combined Raman spectroscopy and ab initio MO calculations. J Mol Struct 2004. [DOI: 10.1016/j.molstruc.2004.01.012] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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Remião F, Milhazes N, Borges F, Carvalho F, Bastos M, Lemos-amado F, Domingues P, Ferrer-Correia A. 434 Analysis of aminochromes by HPLC-photodiode array. Adrenochrome evaluation in rat blood. Toxicol Lett 2003. [DOI: 10.1016/s0378-4274(03)90433-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Garrido EMPJ, Garrido JMPJ, Borges F, Delerue-Matos C. Development of electrochemical methods for determination of tramadol--analytical application to pharmaceutical dosage forms. J Pharm Biomed Anal 2003; 32:975-81. [PMID: 12899984 DOI: 10.1016/s0731-7085(03)00199-7] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
A square-wave voltammetric (SWV) method and a flow injection analysis system with amperometric detection were developed for the determination of tramadol hydrochloride. The SWV method enables the determination of tramadol over the concentration range of 15-75 microM with a detection limit of 2.2 microM. Tramadol could be determined in concentrations between 9 and 50 microM at a sampling rate of 90 h(-1), with a detection limit of 1.7 microM using the flow injection system. The electrochemical methods developed were successfully applied to the determination of tramadol in pharmaceutical dosage forms, without any pre-treatment of the samples. Recovery trials were performed to assess the accuracy of the results; the values were between 97 and 102% for both methods.
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Garrido EM, Lima JLFC, Delerue-Matos C, Borges F, Silva AMS, Piedade JAP, Oliveira Brett AM. Electrochemical and spectroscopic studies of the oxidation mechanism of the herbicide propanil. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2003; 51:876-879. [PMID: 12568542 DOI: 10.1021/jf025957v] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
Electrochemical oxidation of propanil in deuterated solutions was studied by cyclic, differential pulse, and square wave voltammetry using a glassy carbon microelectrode. The oxidation of propanil in deuterated acid solutions occurs at the nitrogen atom of the amide at a potential of +1.15 V vs Ag/AgCl. It was also found that, under the experimental conditions used, protonation at the oxygen atom of propanil occurs, leading to the appearance of another species in solution which oxidizes at +0.60 V. The anodic peak found at +0.79 V vs Ag/AgCl in deuterated basic solutions is related to the presence of an anionic species in which a negative charge is on the nitrogen atom. The electrochemical data were confirmed by the identification of all the species formed in acidic and basic deuterated solutions by means of NMR spectroscopy. The results are supported by electrochemical and spectroscopic studies of acetanilide in deuterated solutions.
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Garrido JMPJ, Delerue-Matos C, Borges F, Macedo TRA, Oliveira-Brett AM. Electrochemical Determination of Dihydrocodeine in Pharmaceuticals. ANAL LETT 2003. [DOI: 10.1081/al-120018246] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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Abstract
Xanthine oxidase (XO) is a highly versatile flavoprotein enzyme, ubiquitous among species (from bacteria to human) and within the various tissues of mammals. The enzyme catalyses the oxidative hydroxylation of purine substrates at the molybdenum centre (the reductive half-reaction) and subsequent reduction of O(2) at the flavin centre with generation of reactive oxygen species (ROS), either superoxide anion radical or hydrogen peroxide (the oxidative half-reaction). Many diseases, or at least symptoms of diseases, arise from a deficiency or excess of a specific metabolite in the body. For an example of an excess of a particular metabolite that produces a disease state is the excess of uric acid which can led to gout. Inhibition of XO decreases the uric acid levels, and results in an antihyperuricemic effect. Allopurinol, first synthesised as a potential anticancer agent, is nowadays a clinically useful xanthine oxidase inhibitor used in the treatment of gout. There is overwhelming acceptance that xanthine oxidase serum levels are significantly increased in various pathological states like hepatitis, inflammation, ischemia-reperfusion, carcinogenesis and aging and that ROS generated in the enzymatic process are involved in oxidative damage. Thus, it may be possible that the inhibition of this enzymatic pathway would be beneficial. In this review the State of the Art will be presented, which includes a summary of the progress made over the past years in the knowledge of the structure and mechanism of the enzyme, associated pathological states, and in the efforts made towards the development of new xanthine oxidase inhibitors.
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Silva FA, Borges F, Ferreira MA. Effects of phenolic propyl esters on the oxidative stability of refined sunflower oil. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2001; 49:3936-3941. [PMID: 11513692 DOI: 10.1021/jf010193p] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
The oxidative stability of refined sunflower oil in the presence and in the absence of propyl caffeate (PC), propyl hydrocaffeate (PHC), propyl ferulate (PF), and propyl isoferulate (PI) has been evaluated according to the Rancimat method. The antioxidant activity of the phenolic derivatives was compared with that obtained with native [alpha-tocopherol (alpha-TOH)] and synthetic [propyl gallate (PG)] antioxidants. The results allow the establishment of a decreasing order of antioxidant power: PG > PHC > PC >> alpha-TOH > PI > PF. The oxidative stability was improved neither by the addition of PF nor by a supplement of alpha-TOH. Moreover, a positive antioxidant effect was obtained for PC that was placed between those of alpha-TOH and PG. The antioxidant activity of PHC was higher than that of its analogue (PC). A dose-dependent effect was observed for PG, PHC, and PC. A chain-breaking mechanism was proposed for the antioxidant activity of propyl phenolic esters because the same ranking order of efficacy was obtained for their antiradical activities evaluated by using the 2,2-diphenyl-1-picrylhydrazyl radical method.
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Lemos-Amado F, Domingues P, Ferrer-Correia A, Remião F, Milhazes N, Borges F, Carvalho FD, Bastos ML. Electrospray tandem mass spectrometry of aminochromes. RAPID COMMUNICATIONS IN MASS SPECTROMETRY : RCM 2001; 15:2466-2471. [PMID: 11746918 DOI: 10.1002/rcm.498] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
The catecholamines adrenaline, noradrenaline, dopamine, dopa and isoprenaline were oxidized into their respective aminochromes: adrenochrome, noradrenochrome, dopaminochrome, dopachrome and isoprenochrome. Tandem mass spectrometry (MS/MS) fragmentation patterns were examined for the five aminochromes in order to establish a general structural assignment of these oxidation products by electrospray mass spectrometry. Although protonated aminochromes undergo similar fragmentation patterns with a characteristic consecutive loss of two carbonyl groups, the presence of different substituents in the parent compounds led to significant changes in the CID spectra. This feature is more evident for isoprenochrome and dopachrome, especially for the latter where the MS/MS spectrum is dominated by the loss of formic acid. A general pattern of fragmentation for aminochromes is proposed, which should provide a suitable basis to aid their characterization in studies in vivo or in vitro.
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Silva FA, Borges F, Guimarães C, Lima JL, Matos C, Reis S. Phenolic acids and derivatives: studies on the relationship among structure, radical scavenging activity, and physicochemical parameters. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2000; 48:2122-2126. [PMID: 10888509 DOI: 10.1021/jf9913110] [Citation(s) in RCA: 248] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
The antiradical activity of caffeic acid (1), dihydrocaffeic acid (5), and their corresponding n-alkyl esters was evaluated by using the 2,2-diphenyl-1-picrylhydrazyl radical (DPPH(*)) method. Dihydrocaffeic acid (5) was the most potent compound, having an antiradical effect higher than that of (+/-)-alpha-tocopherol, whereas caffeic acid (1) was less efficient. Esterification of the carboxyl group of dihydrocaffeic acid (5) had a dramatic effect on its antiradical potency, but similar effects were not observed for caffeic acid (1) derivatives. The n-alkyl esters of both phenolic series had similar potencies, and their antiradical activities were independent of the alkyl chain length. Dose-dependent scavenger effects were found in both series. Acid-base properties of the compounds, evaluated by using potentiometry and spectrophotometry, showed that the catechol moiety had pK(a2) and pK(a3) values of 9. 24-9.02 and 11.38-10.99 in the dihydrocaffeic series and 8.48-8.24 and 11.38-11.07 in the caffeic series, respectively. Antiradical activity and pK(a) values of the compounds were not related.
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Agusto V, Franca I, Mansinho K, Araújo C, Borges F, Champalimaud JL, Poiares-Baptista A, Martins C, Ricardo JL. [Verrucous herpes zoster in AIDS patients]. ACTA MEDICA PORT 1997; 10:497-501. [PMID: 9341044] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
The authors describe a case of disseminated Herpes-Zoster (VZV) in an HIV 1 positive patient with AIDS. Hyperkeratotic characteristics, acyclovir resistance and sensitivity to foscarnet of cutaneous lesions are the most important features of this example. From the casuistics of the department, the authors describe two similar cases and review the medical literature with emphasis on etiopathogenic, diagnostic and therapeutic factors of lesions caused by DNA Virus in immunocompromised hosts.
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Amador P, Borges F, Côrte-Real M. Biochemical characterization of a mutant of the yeast Pichia anomala derepressed for malic acid utilization in the presence of glucose. FEMS Microbiol Lett 1996; 141:227-31. [PMID: 8768527 DOI: 10.1111/j.1574-6968.1996.tb08389.x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
The mutant IGC 40 x 1001 of the yeast Pichia anomala IGC 4380, which displays inverse diauxic growth in a medium with glucose and malic acid, was studied to elucidate the biochemical mechanisms underlying that behavior. Time course changes of enzyme activities during growth of the mutant in that mixture of substrates indicated that the gluconeogenic enzymes remained active during the first phase of diauxic growth, while glycolytic enzyme activities were significantly reduced. This reduction was essentially due to an alteration in the maximum velocity and not in substrate affinity. Malate, citrate, and adenosine triphosphate did not affect significantly the activities of the glucose phosphorylating enzymes in cell extracts of either the mutant or the wild strain. In P. anomala, unlike Saccharomyces cerevisiae, the fructose/glucose phosphorylating ratio was not associated with repression/derepression conditions.
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Jaques AK, Arroja I, Araújo C, Azevedo J, Borges A, Santos I, Cabral A, Campos MJ, Mansinho K, Borges F. [The acquired immunodeficiency syndrome, hypertrophic myocardiopathy and multivalvular infectious endocarditis. Apropos a clinical case]. Rev Port Cardiol 1995; 14:53-8. [PMID: 7695955] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
We present a clinical case of a 33 years old young male, gypsy, intravenous drug abuser with heroine and cocaine and AIDS diagnosis. The clinical anamnesis was mainly fever and systolic heart murmur in a clinical scenario of AIDS. The two-dimensional echocardiographic study was clearly diagnostic of an hypertrophic obstructive cardiomyopathy of the left ventricle. This study showed also the presence of multiple vegetations of the mitral, aortic and pulmonic valves in a clinical setting of an acute Streptococcus Viridans infective endocarditis. In this case report we discuss the incidence of this type of multiple cardiac lesions and particularly the presence of this specific pathogenic agent in this high risk group of patients with intravenous drug abuse and systemic immunosuppression. We pointed out the rarity of these findings of left side valvular vegetations associated with this type of cardiomyopathy and the different factors related to infective endocarditis.
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Borges F, Anderson JV, Volta C, Perry L, Drury PL, Bloom SR, Besser GM, Grossman A. Opioid peptides do not modulate atrial natriuretic peptide or aldosterone release under basal conditions in man. J Endocrinol 1988; 116:313-7. [PMID: 2965206 DOI: 10.1677/joe.0.1160313] [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: 01/03/2023]
Abstract
The effect of two analogues of [Met]-enkephalin, [D-Ala2,N-Phe4,Met(0)-ol5]-enkephalin and its guanyl derivative, on plasma concentrations of atrial natriuretic peptide (ANP) and serum aldosterone in six normal subjects was investigated. All subjects were given a 1 litre water load to inhibit vasopressin release. Both analogues, when injected i.v. at a dose of 100 micrograms, stimulated release of prolactin and GH and inhibited serum cortisol; there was no significant change in blood pressure, pulse rate or urine output. Neither plasma concentrations of ANP nor serum aldosterone levels changed significantly after injection of either analogue at a low or high dose. Naloxone, given i.v. as an 8 mg bolus, also failed to alter concentrations of either ANP or aldosterone, while it significantly stimulated the release of serum LH and cortisol. It was concluded that under basal conditions opiate receptors are unable to modulate plasma ANP or serum aldosterone concentrations.
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78
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Ross RJ, Borges F, Grossman A, Smith R, Ngahfoong L, Rees LH, Savage MO, Besser GM. Growth hormone pretreatment in man blocks the response to growth hormone-releasing hormone; evidence for a direct effect of growth hormone. Clin Endocrinol (Oxf) 1987; 26:117-23. [PMID: 3100110 DOI: 10.1111/j.1365-2265.1987.tb03645.x] [Citation(s) in RCA: 54] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
The effect of pretreatment with biosynthetic methionyl human GH (hGH) on the GH response to GHRH has been studied in normal subjects. Eight volunteers were given either 4 IU hGH or placebo s.c. 12-hourly for 72 h before a GHRH test, or a single s.c. dose of 4 IU hGH 12 h before a GHRH test. Somatomedin-C (Sm-C) levels at the time of the GHRH tests were significantly elevated after treatment with hGH compared to placebo, and the GH response to GHRH was significantly attenuated. A further six subjects were given 2 IU hGH or placebo i.v., and i.v. GHRH 3 h later; there was no rise in Sm-C for the 5 h of the study after either treatment; nevertheless, the response to GHRH was completely abolished by pretreatment with hGH. These results demonstrate that GH can regulate its own secretion independently of changes in Sm-C levels, through a mechanism other than the inhibition of GHRH release. The attenuated response to GHRH in the presence of elevated Sm-C levels may be related to Sm-C, or be a more direct effect of the recently elevated GH levels.
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79
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Delgado JA, Portuondo J, Ravelo H, Tamayo P, Bosch MA, Bosch M, Allende E, Alvarez R, Alvarez H, Fernandez R, Borges F, Jacobs M, Gutierrez A, Casas O, Montero R, San Martin J, Berenguer R, De La Torre J, Llambes J. A field on Che. N Engl J Med 1970; 282:400. [PMID: 4903825 DOI: 10.1056/nejm197002122820725] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
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80
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Viegas LC, Borges F. [Pemphigus and hydrocortisone]. ANNALES DE DERMATOLOGIE ET DE SYPHILIGRAPHIE 1955; 82:635-9. [PMID: 13292794] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 03/06/2023]
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