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1.
Braz J Med Biol Res ; 54(4): e10346, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33624730

RESUMO

The main movements of artistic swimming demand various physical capacities such as flexibility, strength, power, and muscular endurance. The use of ergogenic resources to potentialize performance in this sport, however, is underexplored and deserves investigation. In the present study, we tested whether caffeine ingestion would improve the execution of movements that are essential in a typical figure competition or routines in artistic swimming (i.e., amplitude in the Ariana, height in the Boost and Barracuda, and time maintained in the Stationary Scull techniques). Sixteen experienced female athlete artistic swimmers (17.4±3.2 years of age, 5.6±2.8 years of artistic swimming practice) performed several movements of artistic swimming after having ingested a capsule containing caffeine (5 mg/kg body mass) or cellulose (placebo). Compared to the placebo, caffeine improved latero-lateral amplitude during the Ariana (P=0.035), the height of the Boost and Barracuda (P=0.028 and 0.009), and maintained duration in Stationary Sculling (P=0.012). Bayes factor analysis, however, indicated substantial evidence of a positive effect of caffeine only on the Barracuda and Stationary Scull techniques. These findings indicated that caffeine improved performance during specific artistic swimming movements. Coaches and athletes should consider caffeine ingestion in their supplementation plans.


Assuntos
Desempenho Atlético , Cafeína , Teorema de Bayes , Cafeína/farmacologia , Criança , Pré-Escolar , Ingestão de Alimentos , Feminino , Humanos , Natação
2.
Ticks Tick Borne Dis ; 7(5): 782-787, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-27020736

RESUMO

Human granulocytic anaplasmosis (HGA) is an emerging tick-borne zoonosis worldwide. As is the case for many tick-borne diseases, the epidemiological cycle is associated to the environmental conditions, including the presence of wild vertebrate reservoir hosts, vectors, climate and vegetation. In this study a total number of 87 spleen samples of wild ruminants carcasses from Central Italy, and 77 Ixodes ricinus collected from the same dead animals were screened for Anaplasma phagocytophilum by using Real Time PCR. A. phagocytophilum DNA was detected in 75%, 66.7% and 54.2% of the spleen samples from red deer (Cervus elaphus), Apennine chamois (Rupicapra pyrenaica ornata) and roe deer (Capreolus capreolus) respectively, whereas it was detected in the 31.2% of I. ricinus. A total of 27 positive samples were characterized by sequencing a portion of the groEL gene. Two A. phagocytophilum lineages could clearly be delineated from the phylogenetic tree. Four sequences from red deer, 2 from I. ricinus and 1 from Apennine chamois clustered into lineage I together with those previously described as virulent genotypes related to HGA. The presence of A. phagocytophilum DNA in the Apennine chamois represents the first report for this Italian endemic subspecies.


Assuntos
Anaplasma phagocytophilum/genética , Anaplasma phagocytophilum/patogenicidade , Anaplasmose/microbiologia , Cervos/microbiologia , Reservatórios de Doenças , Ehrlichiose/microbiologia , Ixodes/microbiologia , Anaplasmose/epidemiologia , Animais , Animais Selvagens/microbiologia , Chaperonina 60/genética , Ehrlichiose/epidemiologia , Ehrlichiose/veterinária , Genótipo , Humanos , Itália/epidemiologia , Filogenia , Rupicapra/microbiologia , Baço/microbiologia , Zoonoses
3.
Biochim Biophys Acta ; 925(2): 101-8, 1987 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-2441755

RESUMO

Two new trimethylallopsoralens, 4,7,4'- and 4,7,5'-trimethylallopsoralen, form molecular complexes with DNA and by successive UVA (320-400 nm) irradiation photobind monofunctionally to the macromolecule. The DNA photobinding rates at 365 nm and photobinding quantum yields at 330 nm are markedly higher for 4,7,4'-trimethylallopsoralen than for 4,7,5'-trimethylallopsoralen. Their capacities to generate singlet oxygen in water and benzene are low, particularly for 4,7,4'-trimethylallopsoralen, and the two trimethylallopsoralens completely lack skin phototoxicity on guinea-pig skin. Both compounds show antiproliferative activity in terms of DNA synthesis inhibition in Ehrlich cells and T2 phage infectivity higher than that displayed by angelicin. In view of its monofunctional character, lack of skin phototoxicity, low singlet oxygen yield and antiproliferative activity, 4,7,4'-trimethylallopsoralen deserves further clinical studies as a potential photochemotherapeutic agent.


Assuntos
DNA , Furocumarinas , Terapia PUVA/métodos , Benzeno , Fenômenos Químicos , Físico-Química , Reagentes de Ligações Cruzadas , DNA/biossíntese , Radicais Livres , Furocumarinas/efeitos da radiação , Oxigênio , Fotoquímica , RNA/biossíntese , Fagos T/genética , Água
4.
Pharmacol Ther ; 52(3): 331-63, 1991 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-1820581

RESUMO

Angelicin and some of its derivatives are naturally occuring compounds which show interesting photobiological properties. In this review various aspects of angelicin and its derivatives have been reported. The natural occurrence and the chemical synthesis both of naturally occurring and synthetic angelicins have been reviewed. Photochemical and photophysical properties of angelicins have been considered with particular reference to the capacity to generate active forms of oxygen, photoreactions with nucleic acids, proteins and unsaturated fatty acids. Photobiological effects have been considered: skin phototoxicity, antiproliferative effects, genotoxicity, ability to induce hemolysis in erythrocytes, inactivation of prokaryotic and eukaryotic microorganism and of viruses. The ability of some angelicins to induce photocarcinogenesis has been reviewed as well as in the activity as photochemotherapeutic agents.


Assuntos
Furocumarinas , Tranquilizantes , Animais , Furocumarinas/síntese química , Furocumarinas/química , Furocumarinas/uso terapêutico , Humanos , Fotoquímica , Fotólise/efeitos dos fármacos , Dermatopatias/terapia , Relação Estrutura-Atividade , Tranquilizantes/síntese química , Tranquilizantes/química , Tranquilizantes/uso terapêutico
5.
Rev Sci Tech ; 24(3): 857-68, 2005 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-16642756

RESUMO

Since 2000 Italy has experienced five epidemics of bluetongue, an arthropod-borne disease that affects primarily sheep and asymptomatically cattle, goats and wildlife ruminants. In four years the disease spread through Southern and Central Italy, involving 14 Italian regions out of 20. To control the disease, the Ministry of Health established a surveillance system that included clinical, entomological and serological surveillance elements. The National Reference Centre for Veterinary Epidemiology--Istituto Zooprofilattico Sperimentale dell'Abruzzo e del Molise 'G. Caporale'--developed a Web-based National Information System (NIS) and a Geographical Information System (GIS)to collect and manage data from Veterinary Services across Italy. The system was designed to gather and spread information in order to support the management of control activities and to provide an early warning system. Surveillance data are displayed to the user in different ways: reports, tables and interactive maps.


Assuntos
Bluetongue/epidemiologia , Doenças dos Bovinos/epidemiologia , Sistemas de Informação Geográfica , Doenças das Cabras/epidemiologia , Animais , Animais Domésticos , Animais Selvagens , Bovinos , Surtos de Doenças/veterinária , Cabras , Internet , Itália/epidemiologia , Vigilância de Evento Sentinela/veterinária , Ovinos
6.
J Invest Dermatol ; 97(1): 50-4, 1991 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-2056193

RESUMO

Although psoralens plus UVA radiation (320-400 nm) have been widely used for the treatment of dermatologic diseases, the toxic effects of these agents have led investigators to develop new photochemotherapeutic compounds. One such compound is 4,4',5'-trimethylazapsoralen (TMAP), a new bifunctional molecule. The purpose of this study was to examine the immunologic side effects of repeated treatment of C3H mice with TMAP plus UVA radiation. During this treatment, the number of ATPase+, la+, and Thy-1+ dendritic epidermal cells greatly decreased in the treated site, despite the lack of phototoxicity. The reduction in the number of detectable cutaneous immune cells was accompanied by a decrease in the induction of contact hypersensitivity to dinitrofluorobenzene applied to the treated skin, an impairment in the antigen-presenting activity of draining lymph node cells, and the presence of suppressor lymphoid cells in the spleen of unresponsive mice. Treatment with UVA radiation alone also reduced the number of ATPase+, Ia+, and Thy-1+ cells in the skin, but did not cause any detectable alterations in immune function. This implies that morphologic alterations in these cells do not necessarily indicate loss of function. Thus, although TMAP in combination with UVA radiation is not overtly phototoxic, it is highly immunosuppressive in mice.


Assuntos
Dermatite de Contato/prevenção & controle , Furocumarinas/uso terapêutico , Terapia PUVA , Animais , Células Dendríticas/imunologia , Dinitrofluorbenzeno/imunologia , Feminino , Antígenos de Histocompatibilidade Classe II/imunologia , Linfonodos/imunologia , Camundongos , Camundongos Endogâmicos C3H , Baço/imunologia
7.
J Invest Dermatol ; 73(2): 191-7, 1979 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-458193

RESUMO

Some aspects of the interactions between DNA and 8-methoxypsoralen (8-MOP) in its ground state (complex formation) or in its excited state (photobinding) have been investigated. 8-MOP shows a low affinity towards DNA in the complex formation; this fact minimizes the possible biological consequences deriving from this interaction, when it occurs in vivo. In covalent photobinding to DNA, 8-MOP forms mainly monofunctional adducts, and to a lesser extent bifunctional adducts, showing a behavior similar to that of other linearly condensed furocoumarins (psoralens); the ratio between mono- and bifunctional adducts was found to be 9:1. The covalent photobinding to DNA does not occur at random along the macromolecule, but preferentially at the level of specific receptor sites. The regions having an alternate sequence of A-T seem to be the best receptor sites for the formation of monoadducts while the regions containing an alternate sequence of A-T and C-G appeared to be the preferential sites for the cross-linkage formation.


Assuntos
DNA/metabolismo , Metoxaleno/metabolismo , Sequência de Bases , DNA/efeitos da radiação , Ficusina/metabolismo , Ficusina/efeitos da radiação , Metoxaleno/efeitos da radiação , Modelos Biológicos , Polidesoxirribonucleotídeos/metabolismo , Espectrometria de Fluorescência , Raios Ultravioleta
8.
J Med Chem ; 24(7): 806-11, 1981 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-7277384

RESUMO

The interactions both in the ground and in the excited state between various methylangelicins, previously prepared with the aim to increase the low photobiological activity of the parent angelicin 1, and DNA have been studied. In general, the new methylangelicins show an increased capacity to photobind monofunctionally to DNA and a parallel increment of photobiological activity in comparison with the parent 1. This increase appears to be connected with various factors, such as the augmented affinity toward DNA for the dark complex formation and the electronic effect connected with the introduction into 1 of one or two methyl groups. The new compounds, on the basis of their photobiological activity and their lack of skin phototoxicity, appear as possible agents for the photochemistry of skin diseases characterized by cell hyperproliferation.


Assuntos
DNA/metabolismo , Furocumarinas/metabolismo , Fotoquimioterapia , Psoríase/tratamento farmacológico , Fenômenos Químicos , Química , Dicroísmo Circular , Escuridão , Furocumarinas/uso terapêutico , Humanos , Cinética , Desnaturação de Ácido Nucleico , Fotoquímica , Relação Estrutura-Atividade
9.
J Med Chem ; 27(8): 959-67, 1984 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-6540313

RESUMO

The possible presence of methylpsoralens as undesired inquinants in synthetic methylangelicins has been avoided through a synthetic pathway starting from umbelliferones carrying a methyl group in the 6-position. The new 6-methylangelicins show a high affinity toward DNA, forming in the dark a molecular complex; the complexed angelicins under UV-A irradiation photobind effectively to the macromolecule, forming only monoadducts. The new compounds show an evident antiproliferative activity by inhibiting DNA synthesis on Ehrlich cells; great differences, however, can be seen between the various compounds. All the compounds are lacking of skin erythemogenic activity. Some of the new 6-methylangelicins, evaluated in terms of mutagenic activity, demonstrate to be less effective than 8-methoxypsoralen (8-MOP), used for a comparison. On the basis of antiproliferative activity, lack of skin phototoxicity, and low mutagenicity, two compounds have been chosen for clinical evaluation. The compounds tested on seven psoriatic patients by topical application and UV-A irradiation proved to be more effective than 8-MOP, used in the same conditions.


Assuntos
Furocumarinas/síntese química , Fotoquimioterapia , Psoríase/tratamento farmacológico , Animais , Carcinoma de Ehrlich/metabolismo , Divisão Celular/efeitos dos fármacos , DNA/metabolismo , Replicação do DNA/efeitos dos fármacos , Furocumarinas/uso terapêutico , Humanos , Testes de Mutagenicidade , Pele/efeitos dos fármacos
10.
J Med Chem ; 24(2): 178-84, 1981 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-7205886

RESUMO

With the aim of obtaining new agents for the photochemotherapy of psoriasis, we have prepared monofunctional reagents for DNA by starting from 4,5'-dimethylangelicin (2), an angular furocoumarin, and introducing in a 4'-(hydroxymethyl) (3), 4'-(methoxymethyl) (4), or 4'-(aminomethyl) group (5), in way analogous to what other authors have done previously on trioxsalen, a DNA bifunctional reagent. These new compounds form complexes with DNA in the ground state and by successive irradiation (UV-A) undergo monofunctional photoaddition to the macromolecule. Photobinding to DNA was highest for 3 and gradually lower for 4 and 5, respectively. These compounds do not form interstrand photocross-linkages in DNA and do not show any skin phototoxicity. Fluorimetric studies show that their 4',5' double bond is involved in the photoaddition to DNA. Their photobiological activity evaluated on Ehrlich ascites tumor cells and on T2 phages was strictly connected with their photobinding to DNA. The effect of the introduction of hydroxymethyl and methoxymethyl groups in angular 2 is somewhat similar to that previously described for trioxsalen: the introduction of an aminomethyl group in 2 markedly increases the affinity in the dark for DNA but under UV-A irradiation strongly inhibits photobinding to the macromolecule. By contrast, in the analogous derivative of trioxsalen both the affinity for DNA in the dark and the photobinding to DNA increased.


Assuntos
DNA/metabolismo , Furocumarinas/síntese química , Fotoquimioterapia , Psoríase/tratamento farmacológico , Animais , Furocumarinas/metabolismo , Furocumarinas/farmacologia , Cobaias , Indicadores e Reagentes , Fotoquímica , Pele/efeitos dos fármacos , Solubilidade
11.
J Med Chem ; 26(6): 870-6, 1983 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-6854590

RESUMO

Three derivatives of angelicin (1) [4'-methyl-, 4,4'-dimethyl-, and 4',5-dimethylangelicin (2a-c)] have been prepared with the aim of obtaining new agents for the photochemotherapy of psoriasis. These compounds form a complex in the dark with DNA that shows an affinity for the macromolecule higher than that of the parent angelicin (1). A correlation between their octanol/water partition coefficients and the association constants of the complexes has been observed. Compounds 2a-c photobind to DNA to a much higher extent than 1 and also more effectively than 8-methoxypsoralen (8-MOP), taken as reference compound. When activated with UV-A, the three compounds strongly inactivate T2 phage and inhibit epidermal DNA synthesis in mice. Moreover, they show a mutagenic activity markedly lower than that of 8-methoxypsoralen on Escherichia coli wild-type strain. Due to its lack of skin phototoxicity, its low mutagenic activity, and its antiproliferative activity, 2c was chosen for clinical evaluation. It proved to be effective in clearing psoriasis in two patients.


Assuntos
Furocumarinas/uso terapêutico , Fototerapia , Psoríase/terapia , Animais , Divisão Celular/efeitos dos fármacos , DNA/metabolismo , Epiderme/efeitos dos fármacos , Furocumarinas/síntese química , Humanos , Camundongos , Testes de Mutagenicidade , Solubilidade , Fagos T/efeitos dos fármacos
12.
J Med Chem ; 39(6): 1293-302, 1996 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-8632436

RESUMO

With the aim of obtaining new potential photochemotherapeutic agents, having increased antiproliferative activity and decreased undesired effects, we have prepared some new furoquinolinones. Two of them have been studied in detail: 1,4,6,8-tetramethyl-2H-furo[2,3-h]-quinolin-2-one (8), and 4,6,8,9-tetramethyl-2H-furo[2,3-h]quinolin-2-one (10). These compounds form a molecular complex with DNA, undergoing intercalation inside the duplex macromolecule, as shown by linear flow dichroism. The complexed ligands, by subsequent irradiation with UV-A light, photobind with the macromolecule forming only monocycloadducts with thymine with cis-syn configuration. In order to evaluate the electronic effects induced by the nitrogen atom in position 1 of 8, semiempirical calculations have been performed on both 4,6,4'-trimethylangelicin (TMA) and 8. The results obtained do not clearly differentiate between the two molecules which, at this level of approximation, show the possibility of photoreaction with both the 3,4- and 8,9-olefinic bonds for 8 and the 3,4- and 4',5'-bonds for TMA. In the lower energy conformation of intercalated 8, the furan ring is turned toward the minor groove of the polynucleotide, in such a way that photoreaction of this ring with thymine is favored. These compounds unexpectedly inhibit DNA and RNA synthesis in Ehrlich cells, in the dark. They also show a strong photoantiproliferative activity, 2 orders of magnitude higher than 8-methoxypsoralen (8-MOP), the most used drug for photochemotherapy. Their mutagenic activity on Escherichia coli is similar to that of TMA and 8-MOP. On the basis of these results, the compounds should deserve evaluation of their activity in the treatment of hyperproliferative skin diseases.


Assuntos
Furocumarinas/síntese química , Fotoquimioterapia , Dermatopatias/tratamento farmacológico , DNA/metabolismo , Furocumarinas/farmacologia , Furocumarinas/toxicidade , Mutagênicos/toxicidade , Myoviridae/efeitos dos fármacos , RNA/biossíntese
13.
Acta Biochim Pol ; 43(1): 241-6, 1996.
Artigo em Inglês | MEDLINE | ID: mdl-8790728

RESUMO

For decades the therapeutic properties of psoralens were related to their photochemical reactions with DNA and RNA. Such approach, although fruitful in treatments, did not explain satisfactorily the way of healing of the multitude of diseases manifested through skin disorders. The new research field presented in our review is directed to another target: the lipid components of the cell. The studies on the photobiology of phospholipids may help to elucidate the phototoxic and pigment inducing activity of psoralens.


Assuntos
DNA/efeitos dos fármacos , Furocumarinas/farmacologia , Lipídeos de Membrana/metabolismo , Fosfolipídeos/metabolismo , Fármacos Fotossensibilizantes/farmacologia , RNA/efeitos dos fármacos , Dano ao DNA , Furocumarinas/química , Furocumarinas/uso terapêutico , Humanos , Fármacos Fotossensibilizantes/química , Fármacos Fotossensibilizantes/uso terapêutico , Pigmentos Biológicos/metabolismo , Dermatopatias/tratamento farmacológico , Raios Ultravioleta
14.
Photochem Photobiol ; 59(3): 277-83, 1994 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-8016205

RESUMO

The isolation and characterization of photocycloadducts with pyrimidine bases from DNA samples irradiated (365 nm) in the presence of four 4',5'-substituted methylangelicins was performed. All these furocoumarins yielded mainly the cis-syn furan-side cycloadduct with thymine. For 4',5'-dimethyl-, 5,4',5'-trimethyl- and 6,4',5'-trimethylangelicin this adduct was accompanied by two pyrone-side adducts (cis-syn and cis-anti), whereas the 4,4',5'-trimethyl derivative gave the furan-side adduct with cytosine. The characterization of the regio- and stereochemistry of the adducts was accomplished by 1H NOE (nuclear Overhauser effect) and 1H-13C HMBC (heteronuclear multiple-bond connectivity) spectroscopies. The formation of different cycloadducts in DNA by the various derivatives highlights the role of the methyl groups in determining the regio- and stereochemistry of the cycloaddition.


Assuntos
DNA/efeitos da radiação , Furocumarinas/química , Animais , DNA/química , Furocumarinas/farmacologia , Humanos , Técnicas In Vitro , Masculino , Modelos Moleculares , Fotoquímica , Fotoquimioterapia , Fármacos Fotossensibilizantes/química , Fármacos Fotossensibilizantes/farmacologia , Pirimidinas/química , Pirimidinas/efeitos da radiação , Estereoisomerismo
15.
Photochem Photobiol ; 50(1): 75-84, 1989 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-2762383

RESUMO

The sequence specificity in the photoreaction (365 nm) of 6,4,4'-trimethylangelicin (TMA) with DNA fragments of the lac I gene of Escherichia coli was studied by using DNA sequencing methodology. In order to map the sites of TMA photoaddition, we took advantage of the (3'-5') exonuclease activity associated with T4 DNA polymerase, which is blocked by bulky adducts, such as furocoumarin photoadducts. A quantitative analysis of the sites of photoaddition is reported. TMA was demonstrated to photoreact with thymine and, to a lower extent, to cytosine. AT-rich sequences and TTT sites in a GC context are the most reactive sites towards TMA whereas TA, AT, CA, AC sites are weaker sites with similar reactivity. Cytosines in alternated CG sequences are also targets of TMA photobinding. We observed a less pronounced sequence specificity of TMA than that of other psoralen derivatives already studied (Sage and Moustacchi, 1987; Boyer et al., 1988). A comparison with other furocoumarins 4,4'-dimethylangelicin (4,4'-DMA), 4'-methylangelicin (4'-MA), angelicin, 4,5',8-trimethylpsoralen (TMP) and 8-methoxypsoralen (8-MOP) is also reported. The role of flanking sequence and consequently of the local conformation at the various sites of photoaddition is discussed. A preferential orientation of the TMA molecule during the intercalation in the dark is suggested. Hot alkali treatment of TMA-modified DNA did not reveal any DNA strand breakage due to photooxidized bases.


Assuntos
DNA Bacteriano/metabolismo , Furocumarinas/metabolismo , Sequência de Bases , Fenômenos Químicos , Química , DNA Bacteriano/efeitos da radiação , Eletroforese , Substâncias Intercalantes , Dados de Sequência Molecular , Fotoquímica , Especificidade por Substrato
16.
Photochem Photobiol ; 72(1): 23-7, 2000 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10911725

RESUMO

The crystal structures of 4,6-dimethyltetrahydrobenzoangelicin (THBA), a furocoumarin analog, and of its furan-side cis-syn cycloadduct with thymine formed in the photoreaction with DNA, have been determined. The crystal structure of the latter compound contained only one enantiomeric form corresponding to the addition to a 5'-XpT site. Contrary to most psoralen derivatives studied, THBA showed higher photoreactivity toward synthetic oligonucleotides containing that sequence than toward those with the 5'-TpX sequence.


Assuntos
DNA/química , DNA/efeitos da radiação , Furocumarinas/química , Furocumarinas/efeitos da radiação , Sequência de Bases , Sítios de Ligação , Técnicas In Vitro , Oligodesoxirribonucleotídeos/química , Oligodesoxirribonucleotídeos/efeitos da radiação , Fotoquímica , Timina/química , Timina/efeitos da radiação
17.
Photochem Photobiol ; 53(1): 143-8, 1991 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-2027904

RESUMO

Photochemical and photobiological properties of a new isoster of psoralen, 4,4',5'-trimethyl-8-azapsoralen (4,4',5'-TMAP), have been studied. This compound shows a high DNA-photobinding rate, higher than that of 8-methoxypsoralen (8-MOP), forming both monoadducts and inter-strand cross-links. The yield of cross-links, however, is markedly lower than that of 8-MOP. Antiproliferative activity of 4,4',5'-TMAP, in terms of DNA synthesis inhibition in Ehrlich ascites tumor cells, is higher than that of 8-MOP. Mutagenic activity on E. coli WP2 R46+ cells appeared similar to or even lower than that of 8-MOP. This new compound applied on depilated guinea pig skin and irradiated with UVA did not show any skin-phototoxicity. On the basis of these properties 4,4',5'-TMAP appears to be a potential photochemotherapeutic agent.


Assuntos
Replicação do DNA/efeitos dos fármacos , Furocumarinas/farmacologia , Radiossensibilizantes/farmacologia , Pele/efeitos da radiação , Animais , Carcinoma de Ehrlich/fisiopatologia , DNA/efeitos dos fármacos , DNA/efeitos da radiação , Dano ao DNA , Replicação do DNA/efeitos da radiação , Escherichia coli/efeitos dos fármacos , Escherichia coli/efeitos da radiação , Furocumarinas/síntese química , Cobaias , Camundongos , Testes de Mutagenicidade , Oxigênio/análise , Fotoquímica , Oxigênio Singlete , Pele/efeitos dos fármacos , Pele/patologia , Raios Ultravioleta
18.
Photochem Photobiol ; 68(4): 511-8, 1998 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-9796433

RESUMO

We describe the synthesis of a novel psoralen peroxide 1 that generates on irradiation (350 nm) alkoxyl radicals, namely tert-butoxyl radicals, as confirmed by electron spin resonance studies with the spin trap 5,5-dimethyl-pyrroline-N-oxide. The radical source intercalates into the DNA, which has been demonstrated by linear-flow-dichroism measurements. Thus, the alkoxyl radicals are formed advantageously directly in the DNA matrix. In supercoiled pBR322 DNA, the generation of strand breaks by the photochemically or metal-catalyzed generated alkoxyl radicals is demonstrated. Photosensitization by the psoralen chromophore was excluded because similar substances that do not release radicals caused no DNA damage, nor were the photoproducts of the peroxide 1 active. With calf thymus DNA, 8-oxoGua and small amounts of guanidine-releasing products, e.g. oxazolone, were observed. However, in these reactions the photoproduct also displayed some DNA-oxidizing capacity.


Assuntos
Dano ao DNA , DNA Super-Helicoidal/efeitos da radiação , Substâncias Intercalantes/química , Metoxaleno/análogos & derivados , Plasmídeos/efeitos da radiação , Raios Ultravioleta , Óxidos N-Cíclicos , DNA Super-Helicoidal/química , DNA Super-Helicoidal/efeitos dos fármacos , Espectroscopia de Ressonância de Spin Eletrônica , Radicais Livres , Substâncias Intercalantes/farmacologia , Metoxaleno/síntese química , Metoxaleno/química , Metoxaleno/farmacologia , Desnaturação de Ácido Nucleico , Fotólise , Plasmídeos/química , Plasmídeos/efeitos dos fármacos , Marcadores de Spin
19.
Photochem Photobiol ; 58(2): 226-32, 1993 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-8415914

RESUMO

The effects of mono- and bifunctional furocoumarins plus UVA radiation (PUVA and related treatments) on the human immunodeficiency virus-1 (HIV-1) promoter were studied using HeLa cells stably transfected with the chloramphenicol acetyl transferase gene under the control of the HIV-1 promoter. The experiments were performed with three psoralens (5-methoxypsoralen, 5-MOP; 8-methoxypsoralen, 8-MOP; and 4'-aminomethyl-4,8,5'-trimethylpsoralen, AMT) and four angelicins (angelicin; 4,5'-dimethylangelicin, 4,5'-DMA; 6,4'-dimethylangelicin, 6,4'-DMA; and 4,6,4'-trimethylangelicin, TMA). The drugs alone and UVA radiation alone showed no effect on the HIV promoter. However, when the cells were incubated with the furocoumarins at 0.1-40 micrograms/mL and then irradiated, the HIV promoter was activated in distinct fluence ranges, i.e. (1) no promoter activity was discernible at low fluences (e.g. at 0.1 microgram/mL of 8-MOP up to 100 kJ/m2), (2) as the fluence was increased, the promoter activity increased to reach a maximum (10-50-fold with respect to the unexposed samples), and (3) as the fluence was further increased, the promoter activity decreased. Similar (although shifted on the fluence scale) patterns were observed with either > 340-nm UVA radiation or with UVA radiation contaminated with a small amount of UVB radiation (typical for PUVA lamps). The effective fluences were inversely related to the drug concentration. Experiments with 5-MOP and 8-MOP indicated reciprocity of the drug concentration and radiation fluence. The HIV promoter response patterns were similar for monofunctional angelicins and bifunctional psoralens.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Furocumarinas/farmacologia , HIV/genética , Regiões Promotoras Genéticas/efeitos dos fármacos , Regiões Promotoras Genéticas/efeitos da radiação , Raios Ultravioleta , Sobrevivência Celular/efeitos da radiação , Cloranfenicol O-Acetiltransferase/metabolismo , HIV/efeitos dos fármacos , HIV/efeitos da radiação , Células HeLa , Humanos , Transfecção
20.
Photochem Photobiol ; 63(5): 577-82, 1996 May.
Artigo em Inglês | MEDLINE | ID: mdl-8628748

RESUMO

Photopheresis is an extracorporeal form of photochemotherapy with 8-methoxypsoralen (8-MOP) and UVA (PUVA). Patients ingest 8-MOP and then a psoralen-rich buffy coat is obtained by centrifugation and mixed with saline. This mixture is recirculated through a UVA radiation field and then reinfused. Photopheresis appears to be effective for several T cell-mediated disorders, because the treatment results in a specific immune response against the pathogenic clone of T cells involved. With PUVA therapy, the whole body of the patient is exposed to UVA, after ingestion of 8-MOP. Upon UVA exposure 8-MOP binds to, amongst others, DNA and induces DNA monoadducts and interstrand cross-links. As a result of these photoadducts photocarcinogenicity is a risk in PUVA. In PUVA for psoriasis, it proved that angular furocoumarins, although almost incapable of inducing DNA cross-links (less carcinogenic), are still effective. In order to determine if monoadducts induced by photopheresis could also be effective we used, specifically, 4,6,4'-trimethylangelicin (TMA). In this report, we compare the photodegradation of both TMA and 8-MOP under conditions relevant to the in vivo situation, as well as the effect both compounds have on the viability of rat lymphocytes as measured with the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay. We show that TMA did not induce immunosuppression in vivo, even after extensive irradiation. In addition a dose dependency of 8-MOP/UVA versus the induced immune suppression was carried out. It was shown that there is a log dose/response correlation of r=0.9205.


Assuntos
Furocumarinas/farmacologia , Imunossupressores/farmacologia , Metoxaleno/farmacologia , Fotoferese , Fármacos Fotossensibilizantes/farmacologia , Raios Ultravioleta , Animais , Relação Dose-Resposta à Radiação , Humanos , Cinética , Masculino , Ratos , Ratos Wistar
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