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1.
Sci Rep ; 12(1): 4392, 2022 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-35293387

RESUMO

Giant seafloor craters are known along many a continental margin with recurrent mass-wasting deposits. However, the impact of breakup-related magmatism on the evolution of such craters is barely understood. Using high-quality geophysical datasets, this work examines the genetic relationship among the location of magmatic sills, forced folds and the formation of giant paleo-seafloor craters underneath an ancient mass-transport complex in the Møre and Vøring basins, offshore Norway. The data reveal that forced folding of near-seafloor strata occurred because of the intrusion of several interconnected magmatic sills. Estimates of 1-dimensional uplift based on well data show that uplift occurred due to the intrusion of magma in Upper Cretaceous to Lower Eocene strata. Our findings also prove that subsurface fluid plumbing associated with the magmatic sills was prolonged in time and led to the development of several vertical fluid flow conduits, some of which triggered mass wasting in Neogene to Recent times. The repeated vertical expulsion of subsurface fluids weakened the strata on the continental slope, thereby promoting mass wasting, the selective cannibalization of the paleo-seafloor, and the formation of elongated craters at the basal shear zone of the mass-transport complex. Significantly, the model presented here proves a close link between subsurface magmatic plumbing systems and mass wasting on continental margins.


Assuntos
Fenômenos Geológicos , Erupções Vulcânicas , Noruega
2.
Interação psicol ; 20(2): 144-150, maio-ago. 2016.
Artigo em Português | Index Psicologia - Periódicos | ID: psi-69566

RESUMO

Este artigo tem como objetivo apresentar os resultados de pesquisa em que se buscou delinear osvários conceitos de paz, bem como verificar de que modo esses conceitos se apresentam em facedos responsáveis pelas secretarias municipais de uma cidade de médio porte. Os métodosutilizados foram a revisão sistemática de literatura e uma entrevista semiestruturada com osresponsáveis pelas secretarias. Como resultado, concluiu-se que os trabalhadores conseguemdescrever diversos conceitos de paz e investigou-se como esses conceitos são trabalhados por elesna prática do serviço enquanto atores públicos. Verificou-se, ainda, que a paz é utilizada comocontemplação de um lugar em construção e compreendeu-se que sua produção não diz respeito àsecretaria em que o trabalhador atua, gerando a inexistência de ações e a sua delegação para forada alçada do servidor(AU)


Assuntos
Humanos , Masculino , Feminino , Adulto , Direitos Humanos/psicologia
3.
Neotrop Entomol ; 41(6): 437-41, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23949667

RESUMO

Nymph and adult biology of Glyphepomis spinosa Campos & Grazia (Hemiptera: Pentatomidae) was studied on rice plants under laboratory and greenhouse conditions. The full life cycle of G. spinosa lasted 50.1 day. Nymph development ranged from 2.7 days for the first instar up to 11.9 days for the fifth instar. The egg stage showed the highest per capita rate of mortality (0.16). Nearly 13% of all eggs were laid on the same day. The sex ratio was 0.5. The average hatching rate was 58.0%. Pre-oviposition, oviposition, and post-oviposition periods took 12.9, 34.4, and 6.2 days, respectively.


Assuntos
Hemípteros/crescimento & desenvolvimento , Estágios do Ciclo de Vida , Oryza/parasitologia , Animais , Brasil , Feminino , Masculino , Ninfa/crescimento & desenvolvimento
4.
Curr Med Chem ; 19: 2128-2175, 2012.
Artigo em Inglês | LILACS, Sec. Est. Saúde SP, SESSP-IALPROD, Sec. Est. Saúde SP, SESSP-IALACERVO | ID: biblio-1022985

RESUMO

Infections with protozoan parasites are a major cause of disease and mortality in many tropical countries of the world. Diseases caused by species of the genera Trypanosoma (Human African Trypanosomiasis and Chagas Disease) and Leishmania (various forms of Leishmaniasis) are among the seventeen "Neglected Tropical Diseases" (NTDs) defined as such by WHO due to the neglect of financial investment into research and development of new drugs by a large part of pharmaceutical industry and neglect of public awareness in high income countries. Another major tropical protozoan disease is malaria (caused by various Plasmodium species), which -although not mentioned currently by the WHO as a neglected disease- still represents a major problem, especially to people living under poor circumstances in tropical countries. Malaria causes by far the highest number of deaths of all protozoan infections and is often (as in this review) included in the NTDs. The mentioned diseases threaten many millions of lives world-wide and they are mostly associated with poor socioeconomic and hygienic environment. Existing therapies suffer from various shortcomings, namely, a high degree of toxicity and unwanted effects, lack of availability and/or problematic application under the life conditions of affected populations. Development of new, safe and affordable drugs is therefore an urgent need. Nature has provided an innumerable number of drugs for the treatment of many serious diseases. Among the natural sources for new bioactive chemicals, plants are still predominant. Their secondary metabolism yields an immeasurable wealth of chemical structures which has been and will continue to be a source of new drugs, directly in their native form and after optimization by synthetic medicinal chemistry. The current review, published in two parts, attempts to give an overview on the potential of such plant-derived natural products as antiprotozoal leads and/or drugs in the fight against NTDs.


Assuntos
Plantas Medicinais/metabolismo , Plantas Medicinais/química , Infecções por Protozoários/tratamento farmacológico , Produtos Biológicos/metabolismo , Produtos Biológicos/uso terapêutico , Produtos Biológicos/química , Humanos , Extratos Vegetais/metabolismo , Extratos Vegetais/uso terapêutico , Extratos Vegetais/química , Animais , Fitoterapia , Antiprotozoários/metabolismo , Antiprotozoários/uso terapêutico , Antiprotozoários/química
5.
Pesqui. vet. bras ; 31(4): 336-344, abr. 2011. mapas, tab
Artigo em Português | LILACS | ID: lil-584049

RESUMO

A presente atualização trata de duas das mais importantes doenças sexualmente transmitidas de bovinos, a campilobacteriose genital bovina e a tricomonose genital bovina. São abordados aspectos relacionados à epidemiologia destas doenças, principalmente em relação a sua distribuição no Brasil. Também são revisados aspectos importantes de diagnóstico, incluindo as técnicas e interpretação dos resultados, além de medidas de controle para ambas as doenças.


The present update deals with two of the most important sexually transmitted diseases of cattle: bovine genital campylobacteriosis and bovine genital trichomonosis. Epidemiological aspects, mainly their distribution in Brazil, alongside with their diagnosis in cattle are presented and commented. The main points in their diagnoses, including the description of the techniques and the interpretation of the results are also reviewed. Finally the control and prevention of both diseases are discussed.


Assuntos
Animais , Infecções Sexualmente Transmissíveis/epidemiologia , Infecções Sexualmente Transmissíveis/prevenção & controle , Infecções Sexualmente Transmissíveis/terapia , Infecções Sexualmente Transmissíveis/veterinária
6.
Braz. j. med. biol. res ; 37(5): 649-658, May 2004. ilus, tab, graf
Artigo em Inglês | LILACS | ID: lil-357554

RESUMO

A procedure is described for the rapid determination of the intra-erythrocyte concentration of 6-mercaptopurine (6-MP) and its metabolites, 6-thioguanine nucleotides (6-TGN) and 6-methylmercaptopurine (6-MMP). Erythrocytes (8 x 10(8) cells) in 350 æl Hanks solution containing 7.5 mg dithiothreitol were treated with 50 æl 70 percent perchloric acid. The precipitate was removed by centrifugation (13,000 g) and the supernatant hydrolyzed at 100§C for 45 min. After cooling, 100 æl was analyzed directly by HPLC using a Radialpack Resolve C18 column eluted with methanol-water (7.5:92.5, v/v) containing 100 mM triethylamine. 6-TG, 6-MP and the hydrolysis product of 6-MMP, 4-amino-5-(methylthio)carbonyl imidazole, were monitored at 342, 322 and 303 nm using a Shimadzu SPD-M10A diode array UV detector. The analytes eluted at 5.3, 6.0 and 10.2 min, respectively. The calibration curves were linear (rý > 0.998), and the analytical recoveries were 73.2 percent for 6-TG, 119.1 percent for 6-MP and 97.4 percent for 6-MMP. The intra- and inter-assay variations were highest for 6-MP (9.6 and 14.3 percent, respectively). The lowest detectable concentrations were 3, 3 and 25 pmol/8 x 10(8) erythrocytes for 6-TG, 6-MP and 6-MMP, respectively. The quantification limits (coefficients of variation <15 percent) were 8, 10 and 70 pmol/8 x 10(8) erythrocytes for 6-TG, 6-MP and 6-MMP, respectively. The method was applied to the analysis of 183 samples from 36 children under chemotherapy for acute lymphoblastic leukemia. The concentrations of the metabolites in the red cells of the patients ranged from 0 to 1934 pmol/8 x 10(8) erythrocytes for 6-TGN, and from 0 to 105.8 and 0 to 45.9 nmol/8 x 10(8) erythrocytes for 6-MP and 6-MMP, respectively. The procedure gave results that were in agreement with those obtained with other methods designed to detect cases of non-compliance with treatment, including patient interviews and medical evaluation, among others, demonstrating its applicability to monitoring the treatment of leukemic children.


Assuntos
Humanos , Criança , Mercaptopurina , Cromatografia Líquida de Alta Pressão , Eritrócitos , Leucemia-Linfoma Linfoblástico de Células Precursoras , Biomarcadores , Ditiotreitol , Tioguanina
7.
Braz J Med Biol Res ; 37(5): 649-58, 2004 May.
Artigo em Inglês | MEDLINE | ID: mdl-15107925

RESUMO

A procedure is described for the rapid determination of the intra-erythrocyte concentration of 6-mercaptopurine (6-MP) and its metabolites, 6-thioguanine nucleotides (6-TGN) and 6-methylmercaptopurine (6-MMP). Erythrocytes (8 x 10(8) cells) in 350 microl Hanks solution containing 7.5 mg dithiothreitol were treated with 50 microl 70% perchloric acid. The precipitate was removed by centrifugation (13,000 g) and the supernatant hydrolyzed at 100 degrees C for 45 min. After cooling, 100 microl was analyzed directly by HPLC using a Radialpack Resolve C18 column eluted with methanol-water (7.5:92.5, v/v) containing 100 mM triethylamine. 6-TG, 6-MP and the hydrolysis product of 6-MMP, 4-amino-5-(methylthio)carbonyl imidazole, were monitored at 342, 322 and 303 nm using a Shimadzu SPD-M10A diode array UV detector. The analytes eluted at 5.3, 6.0 and 10.2 min, respectively. The calibration curves were linear (r(2) > 0.998), and the analytical recoveries were 73.2% for 6-TG, 119.1% for 6-MP and 97.4% for 6-MMP. The intra- and inter-assay variations were highest for 6-MP (9.6 and 14.3%, respectively). The lowest detectable concentrations were 3, 3 and 25 pmol/8 x 10(8) erythrocytes for 6-TG, 6-MP and 6-MMP, respectively. The quantification limits (coefficients of variation <15%) were 8, 10 and 70 pmol/8 x 10(8) erythrocytes for 6-TG, 6-MP and 6-MMP, respectively. The method was applied to the analysis of 183 samples from 36 children under chemotherapy for acute lymphoblastic leukemia. The concentrations of the metabolites in the red cells of the patients ranged from 0 to 1934 pmol/8 x 10(8) erythrocytes for 6-TGN, and from 0 to 105.8 and 0 to 45.9 nmol/8 x 10(8) erythrocytes for 6-MP and 6-MMP, respectively. The procedure gave results that were in agreement with those obtained with other methods designed to detect cases of non-compliance with treatment, including patient interviews and medical evaluation, among others, demonstrating its applicability to monitoring the treatment of leukemic children.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Eritrócitos/química , Mercaptopurina/sangue , Leucemia-Linfoma Linfoblástico de Células Precursoras/sangue , Biomarcadores/sangue , Criança , Ditiotreitol/sangue , Ditiotreitol/uso terapêutico , Humanos , Mercaptopurina/uso terapêutico , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamento farmacológico , Tioguanina/sangue , Tioguanina/uso terapêutico
8.
Mem Inst Oswaldo Cruz ; 96(6): 831-3, 2001 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11562711

RESUMO

Polygonum punctatum (Polygonaceae) is an herb known in some regions of Brazil as "erva-de-bicho" and is used to treat intestinal disorders. The dichloromethane extract of the aerial parts of this plant showed strong activity in a bioautographic assay with the fungus Cladosporium sphaerospermum. The bioassay-guided chemical fractionation of this extract afforded the sesquiterpene dialdehyde polygodial as the active constituent. The presence of this compound with antibiotic, anti-inflammatory and anti-hyperalgesic properties in "erva-de-bicho" may account for the effects attributed by folk medicine to this plant species.


Assuntos
Antifúngicos/farmacologia , Cladosporium/efeitos dos fármacos , Polygonum/química , Sesquiterpenos/farmacologia , Antifúngicos/química , Brasil , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Sesquiterpenos/química
9.
Phytochemistry ; 53(8): 877-80, 2000 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10820796

RESUMO

An extract of the aerial parts from Alomia myriadenia Schultz-Bip. ex Baker (Asteraceae) showed significant cytotoxicity against a panel of human cancer cell lines in a screening of extracts from Brazilian Atlantic Forest plant species. Employing a bioassay-linked HPLC-electrospray/MS method, followed by semi-preparative HPLC, the active component was isolated and characterized as a mixture of epimers of the labdane diterpene 12S,16-dihydroxy-ent-labda-7,13-dien-15,16-olide.


Assuntos
Antineoplásicos Fitogênicos/isolamento & purificação , Asteraceae/química , Diterpenos/isolamento & purificação , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/farmacologia , Cromatografia Líquida de Alta Pressão , Diterpenos/química , Diterpenos/farmacologia , Humanos , Espectroscopia de Ressonância Magnética , Espectrometria de Massas , Extratos Vegetais/química , Folhas de Planta/química , Células Tumorais Cultivadas
10.
Mem Inst Oswaldo Cruz ; 95(3): 367-73, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-10800195

RESUMO

In this study, we screened sixty medicinal plant species from the Brazilian savanna ("cerrado") that could contain useful compounds for the control of tropical diseases. The plant selection was based on existing ethnobotanic information and interviews with local healers. Plant extracts were screened for: (a) molluscicidal activity against Biomphalaria glabrata, (b) toxicity to brine shrimp (Artemia salina L.), (c) antifungal activity in the bioautographic assay with Cladosporium sphaerospermum and (d) antibacterial activity in the agar diffusion assay against Staphylococcus aureus, Escherichia coli, Bacillus cereus and Pseudomonas aeruginosa. Forty-two species afforded extracts that showed some degree of activity in one or more of these bioassays.


Assuntos
Antibacterianos/isolamento & purificação , Antifúngicos/isolamento & purificação , Moluscocidas/isolamento & purificação , Plantas Medicinais/química , Animais , Artemia/efeitos dos fármacos , Biomphalaria/efeitos dos fármacos , Brasil , Cladosporium/efeitos dos fármacos , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Extratos Vegetais/uso terapêutico
11.
J Nat Prod ; 62(2): 369-71, 1999 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10075791

RESUMO

7-Epiclusianone, isolated from Rheedia gardneriana, was tested in several biological assays. It was active in vitro against trypomastigotes of Trypanosoma cruzi but inactive in vivo in experimentally infected mice. It was also active against Artemia salina, but inactive against the fungus Cladosporium sphaerospermum and the snail Biomphalaria glabrata.


Assuntos
Antiprotozoários/farmacologia , Benzoquinonas/farmacologia , Árvores/química , Animais , Antiprotozoários/química , Antiprotozoários/isolamento & purificação , Benzofenonas , Benzoquinonas/química , Benzoquinonas/isolamento & purificação , Biomphalaria/efeitos dos fármacos , Cladosporium/efeitos dos fármacos , Decápodes/efeitos dos fármacos , Camundongos , Trypanosoma cruzi/efeitos dos fármacos
12.
Planta Med ; 63(6): 554-5, 1997 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-9434611

RESUMO

The hexane extract from leaves of Vernonia brasiliana (L.) Druce (Compositae) was active in vitro against Plasmodium falciparum and in vivo in mice infected with Plasmodium berghei. This extract was subjected to a bioassay-guided fractionation protocol based on the in vitro model. Lupeol was identified as a compound responsible for the activity, inhibiting the P.falciparum growth by 45% when tested at 25 micrograms/ml. However, this triterpene was inactive in vivo when 15 mg/kg were administered per os during four consecutive days to mice infected with P.berghei. beta-Amyrin and germanicol, isolated from the same fraction that yielded lupeol, were inactive in the in vitro assay.


Assuntos
Antimaláricos/farmacologia , Plantas/química , Triterpenos/farmacologia , Animais , Antimaláricos/isolamento & purificação , Cromatografia Líquida de Alta Pressão , Feminino , Camundongos , Plasmodium berghei/efeitos dos fármacos , Plasmodium falciparum/efeitos dos fármacos , Triterpenos/isolamento & purificação
13.
Planta Med ; 61(1): 85-7, 1995 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-7701002

RESUMO

The diterpene ent-kaur-16-en-19-oic acid (1) was identified as the trypanocidal component of the ethanolic extract from Mikania obtusata D. C. (Asteraceae). This compound presents an IC50 of 0.5 mg/ml (1.66 mM) against the trypomastigote blood form of the Trypanosoma cruzi, the causative agent of Chagas' disease (American trypanosomiasis).


Assuntos
Diterpenos/farmacologia , Plantas/química , Tripanossomicidas/farmacologia , Trypanosoma cruzi/efeitos dos fármacos , Animais , Camundongos
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