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1.
Rev. biol. trop ; 70(1)dic. 2022.
Artigo em Inglês | SaludCR, LILACS | ID: biblio-1387716

RESUMO

Abstract Introduction: The study of herbivory is fundamental in ecology and includes how plants invest in strategies and mechanisms to reduce herbivore damage. However, there is still a lack of information about how the environment, plant density, and functional traits influence herbivory in aquatic ecosystems. Objective: To assess if there is a relationship between herbivory, environmental variables, and plant traits two species of Montrichardia, a neotropical aquatic plant. Methods: In September 2018, we studied 78 specimens of Montrichardia arborescens and 18 of Montrichardia linifera, in 18 sites in Melgaço, Pará, Brazil. On each site, we measured water depth, distance to the margin, and plant density. From plants, we measured plant height and leaf thickness, and photographed the leaves to calculate the specific leaf area and percentage herbivory. To identify anatomical structures, we collected fully expanded leaves from three individuals per quadrat. Results: For M. arborescens, plants with thicker leaves and higher specific leaf area have less herbivore damage. For M. linifera, plants from deeper sites and with thicker leaves had more herbivore damage, while plants that grew farther from the margin had less damage. We found anatomical structures related to defense, such as idioblast cells with phenolic compounds, and cells with solid inclusions that can contribute to avoiding severe damage. Conclusions: Herbivory in these Montrichardia species can be explained by a combination of plant and environmental traits (patch isolation and water depth). The main plant traits are leaf thickness and area, but chemical compounds and solid inclusions also help Montrichardia to sustain less damage than other macrophytes.


Resumen Introducción: La herbivoría es fundamental para comprender cómo las plantas invierten en diferentes estrategias para evitar la depredación, lo que implica diferentes mecanismos de defensa. Factores relacionados con el medio ambiente, la densidad de plantas y/o los rasgos funcionales de las plantas pueden influir en la herbivoría en los ecosistemas acuáticos. Sin embargo, todavía falta información sobre cómo esos factores influyen en la herbivoría en los ecosistemas acuáticos y pueden contribuir a la carga de herbivoría. Objetivo: Evaluar si existe una relación entre la herbivoría y las variables ambientales (p. ej., profundidad del agua y distancia al margen), los factores ecológicos (densidad de plantas) y los rasgos estructurales de las plantas (altura, grosor de la hoja y área foliar) e indicar estructuras anatómicas que actúen junto con los rasgos estructurales en el sistema de defensa de especies de Montrichardia. Métodos: Se evaluaron 96 individuos de Montrichardia spp. (78 de M. arborescens y 18 de M. linifera, en 18 sitios) recolectados en septiembre de 2018. En cada sitio, se midió la profundidad del agua, la distancia al margen y la densidad de plantas. De los individuos, medimos la altura de la planta, el grosor de la hoja y fotografiamos las hojas para calcular el área foliar específica y la cantidad de herbivoría (en porcentaje). Para identificar las estructuras anatómicas relacionadas con la defensa de las plantas, se recogió hojas completamente expandidas de tres individuos por cuadrante. Resultados: Para M. arborescens, las plantas con hojas más gruesas y mayor área foliar específica tienen menos daño por herbivoría. Para M. linifera, las plantas con hojas más gruesas y que habitan en sitios más profundos tienen más daño por herbívoros, mientras que las plantas más alejadas del margen tienen menos daño por herbívoros. Se encontró estructuras anatómicas relacionadas con la defensa, como células idioblásticas con compuestos fenólicos y células con inclusiones sólidas que pueden contribuir a evitar daños severos en las características de las hojas. Conclusiones: Nuestros resultados indican que la herbivoría en las especies de Montrichardia podría explicarse por una combinación de características ambientales (aislamiento del parche y profundidad del agua) y de la planta. Descubrimos que los rasgos de las hojas eran factores importantes que impulsaban los cambios en la carga de herbivoría, especialmente el grosor de las hojas y el área foliar específica. Además, las especies de Montrichardia invierten en compuestos químicos e inclusiones sólidas para evitar daños graves en las hojas y, por lo tanto, pueden sufrir menos daños que otras especies de macrófitos.


Assuntos
Flora Aquática , Herbivoria , Defesa das Plantas contra Herbivoria , Ecossistema Amazônico
2.
Journal of International Pharmaceutical Research ; (6): 619-622, 2020.
Artigo em Chinês | WPRIM | ID: wpr-845143

RESUMO

Based on the exchange and cooperation with international advanced chemical defense emergency rescue forces, combined with years of experience in chemical defense medicine research, and taking Czech National Institute for NBC Protection (SUJCHBO)as an example, we introduce in this paper the advantages and characteristics in the research filed of chemical defense medicine of SUJCHBO. Meanwhile, we discuss the training system, equipment system and scientific research platform construction combined with the enlightenment obtained from SUJCHBO, so as to provide reference for the research of chemical defense medicine and the construction of emergency rescue in China.

3.
Rev. bras. farmacogn ; 25(6): 592-599, Nov.-Dec. 2015. tab, graf
Artigo em Inglês | LILACS | ID: lil-769947

RESUMO

Abstract Sponges of the genus Aplysina are among the most common benthic animals on reefs of the Caribbean, and display a wide diversity of morphologies and colors. Tissues of these sponges lack mineralized skeletal elements, but contain a dense spongin skeleton and an elaborate series of tyrosine-derived brominated alkaloid metabolites that function as chemical defenses against predatory fishes, but do not deter some molluscs. Among the earliest marine natural products to be isolated and identified, these metabolites remain the subject of intense interest for commercial applications because of their activities in various bioassays. In this study, crude organic extracts from 253 sponges from ten morphotypes among the species Aplysina archeri,Aplysina bathyphila,Aplysina cauliformis,Aplysina fistularis,Aplysina fulva,A. insularis, and Aplysina lacunosa were analyzed by liquid chromatography–mass spectrometry (LC–MS) to characterize the pattern of intra- and interspecific variabilities of the twelve major secondary metabolites present therein. Patterns across Aplysina species ranged from the presence of mostly a single compound, fistularin-3, in A. cauliformis, to a mixture of metabolites present in the other species. These patterns did not support the biotransformation hypothesis for conversion of large molecular weight molecules to smaller ones for the purpose of enhanced defense. Discriminant analyses of the metabolite data revealed strong taxonomic patterns that support a close relationship between A. fistularis,A. fulva and A. insularis, while two morphotypes of A. cauliformis (lilac creeping vs. brown erect) were very distinct. Two morphotypes of A. lacunosa, one with hard tissue consistency, the other soft and thought to belong to a separate genus (Suberea), had very similar chemical profiles. Of the twelve metabolites found among samples, variation in fistularin-3, dideoxyfistularin-3 and hydroxyaerothionin provided the most predictive influence in decreasing order. Except for one morphotype, weak relationships were found from within-morphotype analyses of metabolite concentrations as a function of geographic location (Florida, N Bahamas, S Bahamas) and depth (<10 m, 10–20 m, >20 m). Our data suggest that metabolite profiles are strongly influenced by sponge phenotype rather than by the diverse microbiome which many Aplysina species share.

4.
Journal of International Pharmaceutical Research ; (6): 346-350, 2015.
Artigo em Chinês | WPRIM | ID: wpr-845692

RESUMO

The health service of chemical defense medicine is an important guarantee for national security, which has been expanded from dealing with traditional pure chemical warfare to current medical treatment of poisoning caused by public chemical accident, chemical terrorist attack, or future potential toxic agents at the boundary of chemistry and biology. The most recent scientific and technical disciplines, such as synthetic biology, pharmaceutical bioinformatics, nanotechnology, or drug/device combinatorial technology, should be utilized greatly to enhance the ability of the health service of the chemical defense medicine. And it is also important to establish and improve such management practice of emergence medicine as shelf life extension program or emergency use authorization.

5.
Journal of International Pharmaceutical Research ; (6): 346-350, 2015.
Artigo em Chinês | WPRIM | ID: wpr-467818

RESUMO

The health service of chemical defense medicine is an important guarantee for national security, which has been expanded from dealing with traditional pure chemical warfare to current medical treatment of poisoning caused by public chemical accident, chemical terrorist attack, or future potential toxic agents at the boundary of chemistry and biology. The most recent scientific and technical disciplines, such as synthetic biology, pharmaceutical bioinformatics, nanotechnology, or drug/device combinatorial technology, should be utilized greatly to enhance the ability of the health service of the chemical defense medicine. And it is also important to establish and improve such management practice of emergence medicine as shelf life extension program or emergency use authorization.

6.
Chinese Journal of Pharmacology and Toxicology ; (6): 842-846, 2015.
Artigo em Chinês | WPRIM | ID: wpr-482021

RESUMO

″Tianjin Port 8 · 12 Catastrophic Explosion Accident″ affected the national people′s heart. After the disaster,the chemical defense,medical,explosion and so on various relevant profes?sional experts and rescue teams responded to the national call. Taking the bull by the horns,pooling the wisdom and efforts,the experts and rescue teams carried out and implemented the decision spirit of ″it should not hurt one man,and should not appear serious secondary disasters in the late treat?ment″which put forward by the Party Central Committee and State Council. In order to better learn and sum up experience,the cause of the disaster,the disaster rescue and disposal process,the enlighten?ment brought by the disaster and the recommendations deal with unexpected chemical incidents in the future was discussed in this paper.

7.
Braz. j. biol ; 74(3): 545-552, 8/2014. tab, graf
Artigo em Inglês | LILACS | ID: lil-723883

RESUMO

Species of Plocamium are known as prolific sources of halogenated secondary metabolites exhibiting few explored ecological roles. In this study the crude extracts from specimens of P. brasiliense collected in two distinct places, Enseada do Forno and Praia Rasa, Búzios, Estado do Rio de Janeiro, were evaluated as defense against the sea urchin Lytechinus variegatus and the crab Acanthonyx scutiformis. These specimens produce a similar amount of crude extract and also halogenated monoterpene compound-types, but individuals of P. brasiliense from Praia Rasa exhibit a major compound representing about 59% of the total chemicals. Natural concentrations of the crude extracts obtained from both specimens of P. brasiliense significantly inhibited the herbivory by the sea urchin L. variegatus, but had no significant effect on the feeding by A. scutiformis, a crab commonly associated to chemically defended host. Crude extract from P. brasiliense collected at Praia Rasa was more efficient as defense against L. variegatus than that crude extract from populations of this alga from Enseada do Forno, probably due to presence of a major secondary metabolite. These two studied population live under different environmental conditions, but they are only about 30 Km apart. However, it is impossible to affirm that environmental characteristics (abiotic or biotic) would be responsible for the difference of defensive potential found in the two populations of P. brasiliense studied here. Further genetic studies will be necessary to clarify this question and to explain why populations of a single species living in different but close locations can exhibit distinct chemicals.


Espécies de Plocamium são conhecidas como fontes prolíficas de metabólitos secundários halogenados com significados ecológicos pouco conhecidos. Neste trabalho extratos brutos de espécimes de P. brasiliense coletados em duas localidades distintas, Enseada do Forno e Praia Rasa, Búzios, Estado do Rio de Janeiro, foram avaliados como defesa química contra o ouriço Lytechinus variegatus e o caranguejo Acanthonyx scutiformis. Estes espécimes produzem teores similares de extrato bruto e tipos de substâncias monoterpenos halogenados, mas os indivíduos da Praia Rasa possui um componente majoritário representando 59% do total de metabólitos. Concentrações naturais dos extratos brutos destes espécimes inibiram significativamente o consumo por L. variegatus, mas não causaram qualquer efeito sobre A. scutiformis, um caranguejo comumente associado a P. brasiliense, um hospedeiro quimicamente defendido. O extrato bruto de P. brasiliense coletada na Praia Rasa foi mais eficiente como defesa frente a L. variegatus do que aquele obtido de população desta alga da Enseada do Forno, provavelmente pela presença de uma substância majoritária. Estas duas populações de P. brasiliense estudadas vivem sob diferentes condições ambientais, mas distantes somente cerca de 30 km. Entretanto, é impossível afirmar que características ambientais (abióticas ou bióticas) seriam responsáveis pelas diferenças de potencial defensivo encontrados nestas duas populações de P. brasiliense estudadas. Futuros estudos genéticos são necessários para esclarecer esta questão e para explicar porque populações de uma mesma espécie vivendo em regiões tão próximas, mas ambientalmente distintas, produzem substâncias distintas.


Assuntos
Animais , Braquiúros/fisiologia , Herbivoria/fisiologia , Plocamium/química , Ouriços-do-Mar/fisiologia , Braquiúros/classificação , Fenômenos Fisiológicos Vegetais/fisiologia , Ouriços-do-Mar/classificação
8.
Rev. bras. entomol ; 58(2): 161-167, Apr.-June 2014. ilus
Artigo em Inglês | LILACS | ID: lil-714742

RESUMO

Defensive behavior associated with secretions from the prosternal paired glands of the larvae of Heliconius erato phyllis Fabricius (Lepidoptera, Nymphalidae). Our work presents for the first time, the defensive behavior associated with the release of the product of the prosternal paired glands of the larva of Heliconius erato phyllis Fabricius, 1775 (Lepidoptera, Nymphalidae, Heliconiinae). The prosternal glands were first described for larvae of H. erato phyllis. They are formed by two types of glandular structures: the impair gland and the paired glands. The prosternal glands are located within the conical integumentary sac, which in turn is situated on the individual's prosternum. The main goal of this study is to analyze the existence of any secretion from the prosternal paired glands, and check the action mode of this secretion. The methodology used for chemical analysis of the glands included the aeration and, analysis in gas chromatography and gas chromatography-mass spectrometry. The results show that the prosternal glands do not produce volatiles. Bioassays were conducted with simulated and natural attacks and revealed that the prosternal paired glands produce secretions of defense together with silk produced by labials glands as a defense strategy, described for the first time, against ants. The strategy consists in wrapping the ant with silk threads, the entire wrapped object moved to the end of the body, with the aid of the legs and prolegs, and possibly fixed in a nearby place. Evidence for the existence of a conical integumentary sac in larvae of other species and families of Lepidoptera allows us to propose the possibility of occurrence of prosternal paired glands with defensive function in these other groups as well.

9.
Journal of International Pharmaceutical Research ; (6): 667-671, 2014.
Artigo em Chinês | WPRIM | ID: wpr-845820

RESUMO

Owing to the globalization and the fast development of new technologies, new chemical threats are arising, and the strategies for the defense against them are in urgent need to be adapted to the changes. Taking historical events of chemical terrorist attacks as examples, and based on the three major constituents (agent, target and dissemination), we evaluate the key notes in chemical terrorism scenarios and briefly discuss the deficiency of the current countermeasures against contemporary chemical terrorism.

10.
Journal of International Pharmaceutical Research ; (6): 667-671, 2014.
Artigo em Chinês | WPRIM | ID: wpr-457400

RESUMO

Owing to the globalization and the fast development of new technologies, new chemical threats are arising,and the strategies for the defense against them are in urgent need to be adapted to the changes. Taking historical events of chemical terrorist attacks as examples,and based on the three major constituents (agent,target and dissemination),we evaluate the key notes in chemical terrorism scenarios and briefly discuss the deficiency of the current countermeasures against contemporary chemical terrorism .

11.
J. venom. anim. toxins incl. trop. dis ; 18(1): 88-96, 2012. ilus
Artigo em Inglês | LILACS | ID: lil-618194

RESUMO

Cantharidin provides chemical protection for the coleopteran families Meloidae and Oedemeridae. In the present study, it was observed that cantharidin concentration in Hycleus scabiosae was slightly decreased from mated females (mean = 0.011 mg/mg of dry weight) to males (mean = 0.010 mg/mg) and considerably diminished in relation to virgin females (mean = 0.005 mg/mg). Significant concentrations of palasonin (21.69 ng/mg among virgins and 17.49 ng/mg in mated females) and palasoninimide (14.62 ng/mg in virgins and 9.17 ng/mg in mated females) were found in H. scabiosae. Palasonin, palasoninimide and cantharidinimide content of eggs were measured as 5.61, 7.69 and 7.80 ng/mg respectively. Surprisingly, males showed no trace of cantharidin-related compounds (CRCs); therefore CRCs in H. scabiosae could not be transferred from males to females and based on experiments employing its deuterated form, cantharidin is probably independently synthesized in females from the male nuptial transfer. An inseminated female incorporates about 38.5 ng of cantharidin (0.34 percent of the maternal content), 196.35 ng of palasonin (91.82 percent of maternal content) and 269.15 ng of palasoninimide (96.70 percent maternal content) into each egg mass during oviposition. It seems that eggs of this meloid species exploit a different array of protective chemicals by increasing the ratio of CRCs versus cantharidin. CRCs are less toxic than cantharidin; therefore, such compounds might have been deposited in eggs as a safer substitute for cantharidin to provide effective protection, but does not simultaneously harm the susceptible embryo.(AU)


Assuntos
Animais , Masculino , Feminino , Besouros/fisiologia , Cantaridina/metabolismo , Cantaridina/química , Vesícula , Cantaridina/toxicidade , Fatores Sexuais , Fatores Etários
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