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1.
Environ Pollut ; 284: 117209, 2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-33932832

RESUMO

Contaminant levels are lower in Antarctica than elsewhere in the world because of its low anthropogenic activities. However, the northern region of the Antarctic Peninsula, is close to South America and experiences the greatest anthropogenic pressure in Antarctica. Here, we investigated, in two Antarctic Peninsula islands, intra and interspecific factors that influence the concentrations of 17 trace elements (TEs) in blood and feathers of three penguin species breeding sympatrically in relation to their trophic ecology assessed via a stable isotopic approach (C, N and S). Geographical location, foraging zone (δ13C and δ34S) and diet influences the interspecific difference, and sex and maturity stage diet influence the intraspecific difference of Pygoscelis penguins. Penguins from Livingston showed higher values (mean, ng. g-1, dry weight - dw) of Zn (103), Mn (0.3), and Fe (95) than those from King George Island (Zn: 80, Mn: 1.9, and Fe: 11). Gender-related differences were observed, as males showed significantly higher values (mean, ng. g-1, dw) of Rb (3.4) and δ15N in blood of gentoo, and Ca (1344) in Adélie feathers. Chicks of gentoo and Adélie presented higher Zn, Mg, Ca, and Sr and lower 13C values in blood than adults. The highest concentrations (mean, ng. g-1, dw) of Cd (0.2) and Cu (26), and the lowest δ15N values were found in chinstrap. Geographical, intraspecific (i.e., ontogenetic and gender-related) and interspecific differences in feeding seemed to have influenced TE and stable isotope values in these animals. The TE bioaccumulation by penguins may have also been influenced by natural enrichment in environmental levels of these elements, which seems to be the case for Fe, Zn, and Mn. However, the high level of some of the TEs (Mn, Cd, and Cr) may reflect the increase of local and global human activities.


Assuntos
Spheniscidae , Oligoelementos , Animais , Regiões Antárticas , Plumas/química , Humanos , Ilhas , Masculino , América do Sul , Oligoelementos/análise
2.
Semin Cell Dev Biol ; 114: 1-10, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-32893132

RESUMO

Circular RNA (circRNA) is an unusual class of RNA-like structures composed by exonic and/or intronic sequences that are regulated by the backsplicing mechanism and by the spliceosome-mediated machinery. These circular transcripts tend to accumulate during aging in several human tissues, especially in the mammalian brain, and their expression is correlated with the occurrence of several human pathologies, including a broad spectrum of neurological disorders. Previous findings have also shown that circRNAs are significantly present in the neuronal tissue and are up-regulated during neurogenesis, with a significant number been derived from neural genes, suggesting these circular molecules are involved in the cellular and molecular phenotype of our brain. However, the complete biogenesis, the many types of circRNA molecules, and their involvement with neuronal phenotype and with the occurrence of pathologies are still a challenging avenue for researchers. In this updated review, we discuss the current findings of the biogenesis and the diversity of cirRNAs and their molecular involvement in neurological tissue phenotype. We also discuss how some circRNAs can act as sponge molecules, regulating the activity of microRNA expression over gene translation. Finally, we also show the correlation of altered circRNA expression in neurological disorders.


Assuntos
Doenças do Sistema Nervoso/fisiopatologia , RNA Circular/metabolismo , Humanos , Biogênese de Organelas , Fenótipo
3.
Genomics ; 112(5): 3108-3116, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32437852

RESUMO

The ADAM (A Disintegrin And Metalloprotease) gene family encodes proteins with adhesion and proteolytic functions. ADAM proteins are associated with diseases like cancers. Twenty ADAM genes have been identified in humans. However, little is known about the evolution of the family. We analyzed the repertoire of ADAM genes in a vast number of eukaryotic genomes to clarify the main gene copy number expansions. For the first time, we provide compelling evidence that early-branching green algae (Mamiellophyceae) have ADAM genes, suggesting that they originated in the last common ancestor of eukaryotes, before the split of plants, fungi and animals. The ADAM family expanded in early metazoans, with the most significative gene expansion happening during the first steps of vertebrate evolution. We concluded that most of mammal ADAM diversity can be explained by gene duplications in early bone fish. Our data suggest that ADAM genes were lost early in green plant evolution.


Assuntos
Proteínas ADAM/genética , Evolução Molecular , Família Multigênica , Proteínas ADAM/química , Proteínas ADAM/classificação , Animais , Eucariotos/genética , Genômica , Humanos , Filogenia , Plantas/genética , Domínios Proteicos , Vertebrados/genética
4.
Adv Food Nutr Res ; 80: 75-106, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28215329

RESUMO

Diversity is the hallmark of all life forms that inhabit the soil, air, water, and land. All these habitats pose their unique inherent challenges so as to breed the "fittest" creatures. Similarly, the biodiversity from the marine ecosystem has evolved unique properties due to challenging environment. These challenges include permafrost regions to hydrothermal vents, oceanic trenches to abyssal plains, fluctuating saline conditions, pH, temperature, light, atmospheric pressure, and the availability of nutrients. Oceans occupy 75% of the earth's surface and harbor most ancient and diverse forms of organisms (algae, bacteria, fungi, sponges, etc.), serving as an excellent source of natural bioactive molecules, novel therapeutic compounds, and enzymes. In this chapter, we introduce enzyme technology, its current state of the art, unique enzyme properties, and the biocatalytic potential of marine algal, bacterial, fungal, and sponge enzymes that have indeed boosted the Marine Biotechnology Industry. Researchers began exploring marine enzymes, and today they are preferred over the chemical catalysts for biotechnological applications and functions, encompassing various sectors, namely, domestic, industrial, commercial, and healthcare. Next, we summarize the plausible pros and cons: the challenges encountered in the process of discovery of the potent compounds and bioactive metabolites such as biocatalysts/enzymes of biomedical, therapeutic, biotechnological, and industrial significance. The field of Marine Enzyme Technology has recently assumed importance, and if it receives further boost, it could successfully substitute other chemical sources of enzymes useful for industrial and commercial purposes and may prove as a beneficial and ecofriendly option. With appropriate directions and encouragement, marine enzyme technology can sustain the rising demand for enzyme production while maintaining the ecological balance, provided any undesired exploitation of the marine ecosystem is avoided.


Assuntos
Organismos Aquáticos/enzimologia , Bactérias/enzimologia , Biotecnologia/métodos , Fungos/enzimologia , Poríferos/enzimologia , Animais , Clorófitas/enzimologia , Ecossistema , Oceanos e Mares , Phaeophyceae/enzimologia , Rodófitas/enzimologia
5.
Sci Rep ; 6: 27515, 2016 06 09.
Artigo em Inglês | MEDLINE | ID: mdl-27279565

RESUMO

We report on damage to DNA in an aqueous medium induced by ultrashort pulses of intense laser light of 800 nm wavelength. Focusing of such pulses, using lenses of various focal lengths, induces plasma formation within the aqueous medium. Such plasma can have a spatial extent that is far in excess of the Rayleigh range. In the case of water, the resulting ionization and dissociation gives rise to in situ generation of low-energy electrons and OH-radicals. Interactions of these with plasmid DNA produce nicks in the DNA backbone: single strand breaks (SSBs) are induced as are, at higher laser intensities, double strand breaks (DSBs). Under physiological conditions, the latter are not readily amenable to repair. Systematic quantification of SSBs and DSBs at different values of incident laser energy and under different external focusing conditions reveals that damage occurs in two distinct regimes. Numerical aperture is the experimental handle that delineates the two regimes, permitting simple optical control over the extent of DNA damage.


Assuntos
Dano ao DNA/efeitos da radiação , DNA/efeitos da radiação , Lasers/efeitos adversos , Luz/efeitos adversos , Quebras de DNA de Cadeia Dupla/efeitos da radiação , Elétrons/efeitos adversos , Radical Hidroxila/química , Plasmídeos/efeitos da radiação , Água/química
6.
Rev. bras. plantas med ; 17(4): 642-648, out.-dez. 2015. tab, graf
Artigo em Português | LILACS | ID: lil-763224

RESUMO

RESUMO : Aspidosperma subincanum é uma espécie arbórea utilizada em projetos de recuperação de áreas degradadas e como planta medicinal. Levando-se em consideração a importância da espécie, o presente trabalho teve como objetivo definir a temperatura ideal para a germinação de suas sementes. O material vegetal foi coletado na região do Pantanal de Miranda, Mato Grosso do Sul. As sementes foram colocadas em caixas plásticas transparentes em câmara de germinação e submetidas às temperaturas constantes de 20, 25, 30 e 35°C e alternadas de 20-30 e 25-35°C. O delineamento experimental foi inteiramente casualizado, com quatro repetições por tratamento, sendo as médias comparadas pelo teste de Tukey a 5%. A temperatura ideal para a germinação de Aspidosperma subincanum foi a 25°C, com o maior índice de velocidade de germinação, 18,8. Temperaturas mais elevadas (30 e 35°C) causaram a morte dos embriões


ABSTRACT Germination of Aspidosperma subincanum Mart. ex A. DC seeds at different temperatures. The Aspidosperma subincanumem is a tree species used in the recovery of degraded areas projects and as a medicinal plant. Taking into account the importance of the species, the current study aimed to determine which would be the ideal temperature for the germination of their seeds. The plant material was collected in the Pantanal of Miranda, Mato Grosso do Sul. The seeds were placed in transparent boxes in germination chambers and submitted to constant temperatures of, 20, 25, 30 and 35°C and alternated at 20-30 and 25- 35°C, with four replicates per treatment. The statistical design was a completely randomized one. The averages were compared by Tukey test at 5%. The ideal temperature for germination of Aspidosperma subincanum was 25°C. The high temperatures (30 and 35°C) have caused the death of embryos


Assuntos
Temperatura , Germinação/fisiologia , Aspidosperma/classificação , /classificação , Aspidosperma/metabolismo , Plântula/metabolismo
7.
Phys Rev Lett ; 112(13): 138105, 2014 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-24745462

RESUMO

We probe femtosecond laser induced damage to aqueous DNA, relying on strong-field interaction with water wherein electrons and free radicals are generated in situ; these, in turn, interact with DNA plasmids under physiological conditions, producing nicks. Exposure to intense femtosecond pulses of 1350 and 2200 nm light induces single strand breaks and double strand breaks (DSBs) in DNA. At the longer wavelength (and at higher intensities), rotationally hot OH radicals induce DSBs, producing linear DNA. Strand breaks occur due to single or multiple OH hits on DNA. With 2200 nm light, DSBs are formed mostly by the action of two OH radicals; use of OH scavengers establishes that the probability of a two-hit event reduces much faster than a one-hit event as scavenger concentration is increased. Thermal effects do not induce DSBs with 2200 nm light.


Assuntos
Quebras de DNA de Cadeia Dupla , Quebras de DNA de Cadeia Simples , DNA/química , DNA/efeitos da radiação , Radical Hidroxila/química , Lasers , Termodinâmica
8.
Plant Dis ; 98(10): 1437, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30703977

RESUMO

Anthracnose is major disease of pepper (Capsicum annum) in the tropics and causes severe damage both in the field and postharvest. In Brazil, this disease is caused by Colletotrichum acutatum, C. boninense, C. capsici, C. coccodes, and C. gloeosporioides, where the first species is responsible for 70% of all occurrences (3). Recently, C. acutatum has been considered a species complex (1); thus, the aim of this study was to verify the etiology of anthracnose on peppers using a morphological and molecular approaches. In 2011, pepper fruits with typical symptoms of anthracnose (dark, sunken spots with concentric rings of orange conidial masses) were collected in Viçosa, Minas Gerais, Brazil. A single spore isolate was obtained on potato dextrose agar (PDA), and the derived culture was deposited in the Coleção de Culturas de Fungos Fitopatogênicos "Prof. Maria Menezes" (code CMM-4200). The upper side colonies on PDA were gray, cotton-like, and pale gray to pale orange. Conidia were hyaline, aseptate, smooth, straight, cylindrical with round ends or occasionally with end ± acute, 12.5 to 17 µm long and 3.5 to 4 µm wide on synthetic nutrient deficient agar. The isolate was morphologically typical of species belonging to the C. acutatum complex. Molecular identification of the pathogen was carried out and sequences of the regions internal transcribed spacer (ITS), glyceraldehyde-3-phosphate dehydrogenase (GAPDH), and ß-tubulin (ßt) were obtained and deposited in GenBank (Accession Nos. KJ541821 to KJ541823). A search in the Q-bank fungi database using the ITS, ßt, and GAPDH sequences retrieved C. scovillei with 100% identity for all three genes. This pathogen was previously reported in Capsicum spp. only in Thailand, Indonesia, and Japan (1,2). To confirm pathogenicity, drops with 105 spores/ml were deposited in 10 artificially wounded fruits (cv. Itapuã 501 and Melina). In control fruits, drops of sterilized water were deposited onto wounds. The fruits were covered for one day with a transparent plastic bag with moisture supplied by a wet filter paper. The fruits were detached and mature. The bags were removed, and the fruits were incubated for 10 days in a growth chamber at 25°C with a photoperiod of 12 h. After 4 days, gray-brown to black sunken spots with concentric rings were observed on 100% of the wounded fruits that had been inoculated. No disease was observed on the control fruits. The fungus C. scovillei was successfully re-isolated from symptomatic fruits to fulfill Koch's postulates. To our knowledge, this is the first report of anthracnose on pepper fruit caused by C. scovillei in Brazil. Due to the diversity of species that cause anthracnose in Capsicum, future studies using morphological and molecular tools are essential for the correct identification of Colletotrichum spp. on pepper in Brazil. References: (1) U. Damm et al. Stud. Mycol. 73:37, 2012. (2) T. Kanto et al. J. Gen. Plant. Pathol. 80:73, 2014. (3) M. J. Z. Pereira et al. Hortic. Bras. 29:569, 2011.

9.
Phys Rev Lett ; 106(11): 118101, 2011 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-21469899

RESUMO

Single strand breaks are induced in DNA plasmids, pBR322 and pUC19, in aqueous media exposed to strong fields generated using ultrashort laser pulses (820 nm wavelength, 45 fs pulse duration, 1 kHz repetition rate) at intensities of 1-12 TW cm(-2). The strong fields generate, in situ, electrons and radicals that induce transformation of supercoiled DNA into relaxed DNA, the extent of which is quantified. Introduction of electron and radical scavengers inhibits DNA damage; results indicate that OH radicals are the primary (but not sole) cause of DNA damage.


Assuntos
Quebras de DNA de Cadeia Dupla/efeitos da radiação , DNA/efeitos da radiação , Radical Hidroxila/efeitos adversos , Plasmídeos/efeitos da radiação , Radiólise de Impulso/métodos , Elétrons/efeitos adversos , Sequestradores de Radicais Livres/química , Radicais Livres/efeitos adversos , Raios Infravermelhos , Lasers , Água/química
11.
Rev. ciênc. farm ; 25(2): 91-98, 2004. ilus
Artigo em Português | LILACS | ID: lil-418897

RESUMO

A análise de dois fármacos diferentes, mas estruturalmente semelhantes, foi realizada, empregando espectros de reflexão difusa no infravermelho médio com transformada de Fourier (DRIFTS), em associação com a técnica de análise por agrupamentos hierárquicos (AAH). Amostras de 3 diferentes farmácias de manipulação, contendo diclofenaco de sódio 50mg, diclofenaco de potássio 50mg e seus respectivos excipientes, foram analisadas em duplicata por dois analistas. Para a análise multivariada foi empregado o aplicativo Pirouette R 2.7 da Infometrix, selecionando-se o conjunto de regiões dos espectros com maior número de informações. Os dendogramas foram construídos com os dados auto-escalados e correção do espalhamento de luz (MSC), utilizando três tipos de construções: simples, flexível e incremental. Com a aplicação da AAH, constatou-se a formação de diferentes grupos obedecendo à discriminação de cada princípio ativo, indicando seus fornecedores e, em separado, outro grupo. Estes resultados demonstram que a técnica DRIFTS, em conjunto com ferramentas quimioterápicas, constitui uma excelente opção para a caracterização de fármacos, gerando uma inovadora metodologia para auxiliar no controle da qualidade de processos industriais de produção de medicamentos


Assuntos
Anti-Inflamatórios não Esteroides , Diclofenaco/farmacologia , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Avaliação de Medicamentos , Controle de Qualidade
12.
Cochrane Database Syst Rev ; (2): CD003592, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-12804478

RESUMO

BACKGROUND: Pharmacological treatments have been successfully used to treat Generalized Anxiety Disorder (GAD). The mainstay for the pharmacological treatment of GAD in past decades has been the use of benzodiazepine and non benzodiazepine anxiolytics. Data emerging over the last two decades have shown that antidepressants may be equally effective to anxiolytics for treating GAD. The use of antidepressants for treating GAD may be advantageous, due to the fact that GAD presents a high co morbidity ratio with major depressive disorder (62%) and dysthymia (37%). OBJECTIVES: To assess the efficacy and acceptability of antidepressants for treating generalized anxiety disorder. SEARCH STRATEGY: Cochrane Collaboration Depression, Anxiety and Neurosis Controlled Trials Register - CCDANCTR (up to May 2002), Anxiety Neurosis (up to May 2002) and Cochrane Controlled Trials Register (CENTRAL/CCTR) (up to May 2002), MEDLINE (1966 to May 2002), LILACS (1982 to May 2002); reference searching; personal communication; conference abstracts and book chapters on the treatment of generalized anxiety disorder. SELECTION CRITERIA: Randomised controlled trials were included. Exclusion criteria were: non randomised studies; studies which included patients with generalized anxiety disorder and another Axis I co-morbidity. DATA COLLECTION AND ANALYSIS: The data from studies were extracted independently by two reviewers and relative risks, weighted mean difference and number needed to treat were estimated. People who died or dropped out were regarded as having had no improvement. MAIN RESULTS: Antidepressants (imipramine, venlafaxine and paroxetine) were found to be superior to placebo in treating GAD. The calculated NNT for antidepressants in GAD is 5.15. Dropout rates did not differ between antidepressants. Only one study presented data on imipramine and trazodone. Imipramine was chosen as the reference drug and, therefore, data on trazodone could not be included in the meta analysis. Only one study was conducted among children and adolescents (Rynn 2001). The latter study showed very promising results of sertraline in children and adolescents with GAD, which warrants its replication in larger samples. REVIEWER'S CONCLUSIONS: The available evidence suggests that antidepressants are superior to placebo in treating GAD. There is evidence from one trial suggesting that paroxetine and imipramine have a similar efficacy and tolerability. There is also evidence from placebo-controlled trials suggesting that these drugs are well tolerated by GAD patients. Further trials of antidepressants for GAD will help to demonstrate which antidepressants should be used for which patients.


Assuntos
Antidepressivos/uso terapêutico , Transtornos de Ansiedade/tratamento farmacológico , Humanos , Ensaios Clínicos Controlados Aleatórios como Assunto
13.
Rev. Assoc. Med. Bras. (1992) ; 41(3): 249-51, maio-jun. 1995. ilus
Artigo em Português | LILACS | ID: lil-156306

RESUMO

Pneumotórax espontâneo (PE) concomitante às doenças neoplásicas é incomum. Destas, as que mais se associam ao PE säo o câncer de pulmäo e o sarcoma osteogênico com metástases pulmonares. Objetivo. O presente artigo tem o intuito de registrar a ocorrência de PE relacionado a neoplasia de mama e discutir os principais fatores etiopatogênicos envolvidos no evento. Material e Métodos. Os autores descrevem caso de mulher com 43 anos, parda, näo tabagista e protadora de carcinoma ductal infiltrante de mama esquerda, com metástases pulmonares disseminadas bilateralmente. O PE ocorreu na vigência de poliquimioterapia e näo pode ser relacionado a outras causas. Conclusäo. Embora o pulmäo apresente metástases conseqüentes a neoplasia mamária em até 60 por cento dos casos, a coexistência de PE e carcinoma de mama é muito rara. Em revisäo de literatura dos últimos cinco anos, näo se encontraram relatos desta concomitância. Quanto à etiopatogenia do pneumotórax, acredita-se que os fatores relacionados ao episódio sejam múltimos, e os autores fazem comentários a respeito


Assuntos
Humanos , Feminino , Adulto , Neoplasias da Mama/complicações , Carcinoma Ductal de Mama/complicações , Neoplasias Hepáticas/secundário , Neoplasias Hepáticas , Pneumotórax/complicações
14.
Rev Assoc Med Bras (1992) ; 41(3): 249-51, 1995.
Artigo em Português | MEDLINE | ID: mdl-8574239

RESUMO

BACKGROUND: Spontaneous pneumothorax with concomitant neoplastic diseases is unusual. Lung cancer and osteogenic sarcoma with pulmonary metastasis are the neoplasms that most frequently accompany the spontaneous pneumothorax. This article's purposes are to relate the occurrence of spontaneous pneumothorax associated with breast neoplasms and to discuss the main etiopathogenic factors involved in the process. MATERIAL AND METHODS: The authors report a case of a 43-year-old black woman carrier of a left breast ductal carcinoma with bilateral pulmonary metastasis. Spontaneous pneumothorax appeared during multidrug chemotherapy, so it cannot be related to other causes. CONCLUSIONS: Even though breast neoplasms cause lung metastases in about 60% of the cases, the coexistence of spontaneous pneumothorax and breast carcinoma is very rare. There was no report of this topic in the medical literature review during the last five years. The authors believe and discuss the multiple pneumothorax etiopathogenic factors related to this case.


Assuntos
Neoplasias da Mama/patologia , Carcinoma Ductal de Mama/secundário , Neoplasias Pulmonares/secundário , Pneumotórax/etiologia , Adulto , Carcinoma Ductal de Mama/complicações , Feminino , Humanos , Neoplasias Pulmonares/complicações
15.
J. bras. urol ; 9(4): 165-6, 1983.
Artigo em Português | LILACS | ID: lil-18765

RESUMO

Os autores apresentam um caso de fratura de penis em paciente jovem durante o intercurso sexual. Comentam sobre a etiologia, quadro clinico e o tratamento, ressaltando a importancia da cirurgia imediata


Assuntos
Adulto , Humanos , Masculino , Fraturas Ósseas , Pênis
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