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1.
Aust Endod J ; 2024 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-38963178

RESUMO

To evaluate the effects of the association of host defence peptide IDR-1002 and ciprofloxacin on human dental pulp cells (hDPSCs). hDPSCs were stimulated with ciprofloxacin and IDR-1002. Cell viability (by MTT assay), migration capacity (by scratch assay), production of inflammatory and anti-inflammatory mediators by hDPSCs (RT-PCR) and osteogenic differentiation (alizarin red staining) were evaluated. Phenotypic profile of hDPSCs demonstrated 97% for positive marked mesenchymal stem cell. Increased pulp cell migration and proliferation were observed after 24 and 48 h of exposure to IDR-1002 with ciprofloxacin. Mineral matrix formation by hDPSCs was observed of the association while its reduction was observed in the presence of peptide. After 24 h, the association between ciprofloxacin and IDR-1002 significantly downregulated TNFRSF-1, IL-1ß, IL-8, IL-6 and IL-10 gene expression (p ≤ 0.0001). The association between the IDR-1002 and ciprofloxacin showed favourable immunomodulatory potential, emerging as a promising option for pulp revascularisation processes.

2.
J Exp Biol ; 227(12)2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38773949

RESUMO

Bees use thoracic vibrations produced by their indirect flight muscles for powering wingbeats in flight, but also during mating, pollination, defence and nest building. Previous work on non-flight vibrations has mostly focused on acoustic (airborne vibrations) and spectral properties (frequency domain). However, mechanical properties such as the vibration's acceleration amplitude are important in some behaviours, e.g. during buzz pollination, where higher amplitude vibrations remove more pollen from flowers. Bee vibrations have been studied in only a handful of species and we know very little about how they vary among species. In this study, we conducted the largest survey to date of the biomechanical properties of non-flight bee buzzes. We focused on defence buzzes as they can be induced experimentally and provide a common currency to compare among taxa. We analysed 15,000 buzzes produced by 306 individuals in 65 species and six families from Mexico, Scotland and Australia. We found a strong association between body size and the acceleration amplitude of bee buzzes. Comparison of genera that buzz-pollinate and those that do not suggests that buzz-pollinating bees produce vibrations with higher acceleration amplitude. We found no relationship between bee size and the fundamental frequency of defence buzzes. Although our results suggest that body size is a major determinant of the amplitude of non-flight vibrations, we also observed considerable variation in vibration properties among bees of equivalent size and even within individuals. Both morphology and behaviour thus affect the biomechanical properties of non-flight buzzes.


Assuntos
Vibração , Animais , Abelhas/fisiologia , Fenômenos Biomecânicos , Tamanho Corporal , Polinização/fisiologia , México , Austrália , Escócia , Comunicação Animal
3.
J Plant Physiol ; 297: 154259, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38705079

RESUMO

Management of the plant microbiome may help support food needs for the human population. Bacteria influence plants through enhancing nutrient uptake, metabolism, photosynthesis, biomass production and/or reinforcing immunity. However, information into how these microbes behave under different growth conditions is missing. In this work, we tested how carbon supplements modulate the interaction of Pseudomonas chlororaphis with Arabidopsis thaliana. P. chlororaphis streaks strongly repressed primary root growth, lateral root formation and ultimately, biomass production. Noteworthy, increasing sucrose availability into the media from 0 to 2.4% restored plant growth and promoted lateral root formation in bacterized seedlings. This effect could not be observed by supplementing sucrose to leaves only, indicating that the interaction was strongly modulated by bacterial access to sugar. Total phenazine content decreased in the bacteria grown in high (2.4%) sucrose medium, and conversely, the expression of phzH and pslA genes were diminished by sugar supply. Pyocyanin antagonized the promoting effects of sucrose in lateral root formation and biomass production in inoculated seedlings, indicating that this virulence factor accounts for growth repression during the plant-bacterial interaction. Defence reporter transgenes PR-1::GUS and LOX2::GUS were induced in leaves, while the expression of the auxin-inducible, synthetic reporter gene DR5::GUS was enhanced in the roots of bacterized seedlings at low and high sucrose treatments, which suggests that growth/defence trade-offs in plants are critically modulated by P. chlororaphis. Collectively, our data suggest that bacterial carbon nutrition controls the outcome of the relation with plants.


Assuntos
Arabidopsis , Ácidos Indolacéticos , Fenazinas , Raízes de Plantas , Pseudomonas chlororaphis , Sacarose , Sacarose/metabolismo , Arabidopsis/microbiologia , Arabidopsis/metabolismo , Arabidopsis/genética , Raízes de Plantas/microbiologia , Raízes de Plantas/metabolismo , Pseudomonas chlororaphis/metabolismo , Fenazinas/metabolismo , Ácidos Indolacéticos/metabolismo
4.
Mol Ecol ; 33(8): e17321, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38529721

RESUMO

Fundamental to holobiont biology is recognising how variation in microbial composition and function relates to host phenotypic variation. Sponges often exhibit considerable phenotypic plasticity and also harbour dense microbial communities that function to protect and nourish hosts. One of the most prominent sponge genera on Caribbean coral reefs is Agelas. Using a comprehensive set of morphological (growth form, spicule), chemical and molecular data on 13 recognised species of Agelas in the Caribbean basin, we were able to define only five species (=clades) and found that many morphospecies designations were incongruent with phylogenomic and population genetic analyses. Microbial communities were also strongly differentiated between phylogenetic species, showing little evidence of cryptic divergence and relatively low correlation with morphospecies assignment. Metagenomic analyses also showed strong correspondence to phylogenetic species, and to a lesser extent, geographical and morphological characters. Surprisingly, the variation in secondary metabolites produced by sponge holobionts was explained by geography and morphospecies assignment, in addition to phylogenetic species, and covaried significantly with a subset of microbial symbionts. Spicule characteristics were highly plastic, under greater impact from geographical location than phylogeny. Our results suggest that while phenotypic plasticity is rampant in Agelas, morphological differences within phylogenetic species affect functionally important ecological traits, including the composition of the symbiotic microbial communities and metabolomic profiles.


Assuntos
Agelas , Poríferos , Animais , Filogenia , Região do Caribe , Índias Ocidentais , Recifes de Corais , Poríferos/genética
5.
Plants (Basel) ; 13(4)2024 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-38498429

RESUMO

This study highlights Adesmia pinifolia, a native high-Andean species, as a potential candidate for the phytoremediation of soils contaminated with Cd and Hg. In this work, a semi-hydronic assay with different doses of Cd (3, 4.5, and 6 mg L-1) and Hg (0.8, 1.2, and 1.6 mg L-1) was analysed to evaluate the establishment of plants, antioxidant defence systems, oxidative stress, and the ability to accumulate heavy metals. The results indicate high survival rates (>80%); however, Cd significantly reduced shoot and root biomass, while Hg increased root biomass with the 1.6 mg L-1 treatment. Cd and Hg tend to accumulate more in roots (2534.24 µg/g and 596.4 µg g-1, respectively) compared to shoots (398.53 µg g-1 and 140.8 µg g-1, respectively). A significant decrease in the bioconcentration factor of Cd and Hg in roots was observed as metal levels increased, reaching the maximum value at 3 mg L-1 (805.59 ± 54.38) and 0.8 mg L-1 (804.54 ± 38.09). The translocation factor, <1 for both metals, suggests that translocation from roots to shoots is limited. An overproduction of reactive oxygen species (ROS) was observed, causing lipid peroxidation and oxidative damage to plant membranes. Tolerance strategies against subsequent toxicity indicate that enhanced glutathione reductase (GR) activity and glutathione (GSH) accumulation modulate Cd and Hg accumulation, toxicity, and tolerance.

6.
Plants (Basel) ; 13(3)2024 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-38337900

RESUMO

Spiders, abundant and diverse arthropods which occur in vegetation, have received little attention in studies investigating spider-plant interactions, especially in plants which have extrafloral nectaries (EFNs). This study examines whether spiders attracted to EFNs on the plant Heteropterys pteropetala (Malpighiaceae) function as biological protectors, mitigating leaf herbivory and positively impacting plant fitness, through manipulative experiments. Spiders are attracted to EFNs because, in addition to consuming the resource offered by these structures, they also consume the herbivores that are attracted by the nectar. At the same time, we documented the reproductive phenology of the plant studied and the abundance of spiders over time. Our results revealed that the plant's reproductive period begins in December with the emergence of flower buds and ends in April with the production of samarids, fruits which are morphologically adapted for wind dispersal, aligning with the peak abundance of spiders. Furthermore, our results demonstrated that spiders are attracted to plants that exude EFNs, resulting in a positive impact on reducing leaf area loss but with a neutral effect on protecting reproductive structures. By revealing the protective function of spiders' vegetative structures on plants, this research highlights the ecological importance of elucidating the dynamics between spiders and plants, contributing to a deeper understanding of ecosystems.

7.
Primates ; 65(1): 61-68, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37938471

RESUMO

Socioecological models predict that disputes between primate groups will be more intense than those within groups, given that the systematic loss of contests over a given resource will restrict the access of all of the members of that group to that resource. Higher levels of aggression are also expected for provisioned resources that have a more lucrative cost:benefit ratio. The levels of aggression in and between two free-ranging tufted capuchin monkey (Sapajus libidinosus) groups in the context of daily provisioning with bananas were evaluated. The aim of a complementary analysis was to identify possible predictors of the frequency of disputes at the site of the provisioned resource. The disputes were recorded using all-events sampling, while the social behaviour of the study groups was recorded by instantaneous scan sampling. The data were analysed using t-test, Mann-Whitney's U, and generalised linear modelling. Between-group disputes were no more intense than within-group events, and did not involve more individuals, or more adult females. The frequency of disputes increased as the number of individuals eating bananas increased. No evidence was found that disputes between groups were any more intense than those within groups. Dominance patterns may have affected these findings, by mediating intergroup disputes. An increase in the number of competitors affected the frequency of disputes at the site of the provisioned resource.


Assuntos
Cebinae , Dissidências e Disputas , Feminino , Animais , Comportamento Social , Agressão , Sapajus apella , Cebus
8.
Plants (Basel) ; 12(19)2023 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-37836152

RESUMO

Sapindales is a large order with a great diversity of nectaries; however, to date, there is no information about extrafloral nectaries (EFN) in Sapindaceae, except recent topological and morphological data, which indicate an unexpected structural novelty for the family. Therefore, the goal of this study was to describe the EFN in Sapindaceae for the first time and to investigate its structure and nectar composition. Shoots and young leaves of Urvillea ulmacea were fixed for structural analyses of the nectaries using light and scanning electron microscopy. For nectar composition investigation, GC-MS and HPLC were used, in addition to histochemical tests. Nectaries of Urvillea are circular and sunken, corresponding to ocelli. They are composed of a multiple-secretory epidermis located on a layer of transfer cells, vascularized by phloem and xylem. Nectar is composed of sucrose, fructose, xylitol and glucose, in addition to amino acids, lipids and phenolic compounds. Many ants were observed gathering nectar from young leaves. These EFNs have an unprecedented structure in the family and also differ from the floral nectaries of Sapindaceae, which are composed of secretory parenchyma and release nectar through stomata. The ants observed seem to protect the plant against herbivores, and in this way, the nectar increases the defence of vegetative organs synergistically with latex.

9.
Rev. crim ; 65(2): 43-55, 20230811.
Artigo em Espanhol | LILACS | ID: biblio-1537674

RESUMO

El derecho a la defensa es una garantía que forma parte del debido proceso de conformidad con lo pautado en la Constitución de la República Bolivariana de Venezuela. Los funcionarios que forman parte de los órganos policiales colaboran con el Ministerio Público en la persecución de hechos delictivos, y en el ejercicio de sus funciones pueden incurrir en conductas que den lugar a la instrucción de procedimientos en su contra, por lo que la investigación analizó el derecho a la defensa de funcionarios policiales en procesos por actos de servicio en la Policía del Estado Mérida. Se realizó un estudio de campo, descriptivo, cualitativo y se aplicó un cuestionario contentivo de diez preguntas con varias alternativas de respuestas a una muestra de 50 personas. Los resultados permitieron inferir que las situaciones de servicio se generan principalmente por aprehensiones en flagrancia y procedimientos de captura, en cuyo cumplimiento los funcionarios pueden incurrir en irregularidades que den lugar a la apertura de investigaciones disciplinarias y penales, razón por la cual se requiere de una defensa pública especializada. Se concluyó que el derecho a la defensa se hará valer en las instancias administrativas y jurisdiccionales, y se recomienda la puesta en funcionamiento de la Defensoría Pública con competencia en materia penal policial.


The right to a defence is a guarantee that forms part of due process in accordance with the Constitution of the Bolivarian Republic of Venezuela. Police officers collaborate with the Public Prosecutor's Office in the prosecution of criminal acts, and in the exercise of their duties may engage in conduct that may lead to proceedings being brought against them. For this reason, the research analysed the right to defence of police officers involved in proceedings for acts of service in the Mérida State Police. A descriptive, qualitative field study was carried out and a questionnaire containing ten questions with several alternative answers was applied to a sample of 50 people. The results allowed us to infer that service situations are mainly generated by apprehensions in flagrante delicto and arrest procedures, in which officials may incur in irregularities that lead to the opening of disciplinary and criminal investigations, which is why specialised public defence is required. It was concluded that the right to defence should be asserted in administrative and jurisdictional instances, and it is recommended that a Public Defence Office with competence in police criminal matters be set up.


O direito à defesa é uma garantia que faz parte do devido processo legal, de acordo com a Constituição da República Bolivariana da Venezuela. Os funcionários que fazem parte dos órgãos policiais colaboram com o Ministério Público a persecução de fatos delituosos e, no exercício de suas funções, podem ter condutas que podem levar à instauração de processos contra eles. Por essa razão, na pesquisa, foi analisado o direito de defesa dos policiais em processos por atos de serviço na Polícia Estadual de Mérida. Foi realizado um estudo de campo descritivo e qualitativo e um questionário com 10 perguntas com várias alternativas de resposta foi aplicado a uma amostra de 50 pessoas. Os resultados permitiram inferir que as situações de serviço são geradas principalmente por apreensões em flagrante delito e procedimentos de prisão, nos quais os agentes podem incorrer em irregularidades que levam à abertura de investigações disciplinares e criminais, razão pela qual é necessária a defesa pública especializada. Concluiu-se que o direito de defesa deve ser afirmado nas instâncias administrativas e jurisdicionais, sendo recomendada a criação da Defensoria Pública com competência em matéria penal policial.


Assuntos
Humanos
10.
Naturwissenschaften ; 110(4): 31, 2023 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-37389663

RESUMO

Plant strategies against herbivores are classically divided into chemical, physical, biotic defences. However, little is known about the relative importance of each type of plant defence, especially in the same species. Using the myrmecophyte Triplaris americana (both with and without ants), and the congeneric non-myrmecophyte T. gardneriana, we tested whether ant defence is more effective than other defences of naturally ant-free myrmecophytes and the non-myrmecophyte congeneric species, all spatially co-occurring. In addition, we investigated how plant traits vary among plant groups, and how these traits modulate herbivory. We sampled data on leaf area loss and plant traits from these tree groups in the Brazilian Pantanal floodplain, and found that herbivory is sixfold lower in plants with ants than in ant-free plants, supporting a major role of biotic defences against herbivory. Whereas ant-free plants had more physical defences (sclerophylly and trichomes), they had little effect on herbivory-only sclerophylly modulated herbivory, but with opposite effects depending on ants' presence and species identity. Despite little variation in the chemicals among plant groups, tannin concentrations and δ13C signatures negatively affected herbivory in T. americana plants with ants and in T. gardneriana, respectively. We showed that ant defence in myrmecophytic systems is the most effective against herbivory, as the studied plants could not fully compensate the lack of this biotic defence. We highlight the importance of positive insect-plant interactions in limiting herbivory, and therefore potentially plant fitness.


Assuntos
Formigas , Árvores , Animais , Brasil , Herbivoria , Fenótipo
11.
Front Immunol ; 14: 1175786, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37256140

RESUMO

Background: The plant immune response to DNA is highly self/nonself-specific. Self-DNA triggered stronger responses by early immune signals such as H2O2 formation than nonself-DNA from closely related plant species. Plants lack known DNA receptors. Therefore, we aimed to investigate whether a differential sensing of self-versus nonself DNA fragments as damage- versus pathogen-associated molecular patterns (DAMPs/PAMPs) or an activation of the DNA-damage response (DDR) represents the more promising framework to understand this phenomenon. Results: We treated Arabidopsis thaliana Col-0 plants with sonicated self-DNA from other individuals of the same ecotype, nonself-DNA from another A. thaliana ecotype, or nonself-DNA from broccoli. We observed a highly self/nonself-DNA-specific induction of H2O2 formation and of jasmonic acid (JA, the hormone controlling the wound response to chewing herbivores) and salicylic acid (SA, the hormone controlling systemic acquired resistance, SAR, to biotrophic pathogens). Mutant lines lacking Ataxia Telangiectasia Mutated (ATM) or ATM AND RAD3-RELATED (ATR) - the two DDR master kinases - retained the differential induction of JA in response to DNA treatments but completely failed to induce H2O2 or SA. Moreover, we observed H2O2 formation in response to in situ-damaged self-DNA from plants that had been treated with bleomycin or SA or infected with virulent bacteria Pseudomonas syringae pv. tomato DC3000 or pv. glycinea carrying effector avrRpt2, but not to DNA from H2O2-treated plants or challenged with non-virulent P. syringae pv. glycinea lacking avrRpt2. Conclusion: We conclude that both ATM and ATR are required for the complete activation of the plant immune response to extracellular DNA whereas an as-yet unknown mechanism allows for the self/nonself-differential activation of the JA-dependent wound response.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Ataxia Telangiectasia , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Proteínas Mutadas de Ataxia Telangiectasia/genética , DNA , Dano ao DNA , Hormônios , Peróxido de Hidrogênio
12.
J Exp Bot ; 74(15): 4613-4627, 2023 08 17.
Artigo em Inglês | MEDLINE | ID: mdl-37115640

RESUMO

Few studies have explored the phenotypic plasticity of nectar production on plant attractiveness to ants. Here, we investigate the role of extrafloral nectary (EFN) size on the productivity of extrafloral nectar in three sympatric legume species. We hypothesized that plant species with larger EFNs (i) have higher induced nectar secretion after herbivory events, and (ii) are more likely to interact with more protective (i.e. dominant) ant partners. We target 90 plants of three Chamaecrista species in the field. We estimated EFN size and conducted field experiments to evaluate any differences in nectar traits before and after leaf damage to investigate the phenotypic plasticity of nectar production across species. We conducted multiple censuses of ant species feeding on EFNs over time. Plant species increased nectar descriptors after leaf damage, but in different ways. Supporting our hypothesis, C. duckeana, with the largest EFN size, increased all nectar descriptors, with most intense post-herbivory-induced response, taking its place as the most attractive to ants, including dominant species. EFN size variation was an excellent indicator of nectar productivity across species. The higher control over reward production in plants with larger sized EFNs reflects an induction mechanism under damage that reduces costs and increases the potential benefits of indirect biotic defences.


Assuntos
Formigas , Animais , Formigas/fisiologia , Néctar de Plantas , Simbiose , Herbivoria/fisiologia , Folhas de Planta/fisiologia , Plantas
13.
J Exp Bot ; 74(9): 2891-2911, 2023 04 27.
Artigo em Inglês | MEDLINE | ID: mdl-36723875

RESUMO

Climate change has intensified the infection of tomato plants by pathogens such as Pseudomonas syringae pv. tomato (Pst). Rootstocks may increase plant tolerance to leaf phytopathogens. The aim of this study was to evaluate the effects of the tolerant Poncho Negro (R) tomato rootstock on physiological defence and the role of hydrogen sulfide (H2S) in susceptible Limachino (L) tomato plant responses to Pst attack. Ungrafted (L), self-grafted (L/L), and grafted (L/R) plants were infected with Pst. Rootstock increased the concentration of antioxidant compounds including ascorbate in the scion. Tolerant rootstock induced an increase of H2S in the scion, which correlated with enhanced expression of the SlAPX2 gene. A high accumulation of salicylic acid was observed in Pst-inoculated grafted L/L and L/R plants, but this was higher in L/R plants. The increase of H2S during Pst infection was associated with a reduction of ethylene in L/R plants. Our study indicates that the Poncho Negro rootstock reduced the symptoms of bacterial speck disease in the Limachino tomato plants, conferring tolerance to Pst infection. This study provides new knowledge about the impact of rootstock in the defence of tomato plants against leaf pathogens that could be used in sustainable management of tomato cultivation.


Assuntos
Pseudomonas syringae , Solanum lycopersicum , Solanum lycopersicum/genética , Plantas , Folhas de Planta/fisiologia , Doenças das Plantas/microbiologia
14.
Microorganisms ; 10(12)2022 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-36557640

RESUMO

Opportunistic pathogenic fungi arise in agricultural crops as well as in surrounding human daily life. The recent increase in antifungal-resistant strains has created the need for new effective antifungals, particularly those based on plant secondary metabolites, such as capsaicinoids and capsinoids produced by Capsicum species. The use of such natural compounds is well-aligned with the One Health approach, which tries to find an equilibrium among people, animals, and the environment. Considering this, the main objective of the present work is to review the antifungal potential of capsaicinoids and capsinoids, and to evaluate the environmental and health impacts of biofungicides based on these compounds. Overall, capsaicinoids and their analogues can be used to control pathogenic fungi growth in plant crops, as eco-friendly alternatives to pest management, and assist in the conservation and long-term storage of agrifood products. Their application in different stages of the agricultural and food production chains improves food safety, nutritional value, and overcomes antimicrobial resistance, with a lower associated risk to humans, animals, and the environment than that of synthetic fungicides and pesticides. Nevertheless, research on the effect of these compounds on bee-like beneficial insects and the development of new preservatives and packaging materials is still necessary.

15.
Plants (Basel) ; 11(24)2022 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-36559679

RESUMO

Plants have evolved multiple mechanisms to defend themselves from their multiple herbivores. Thus, being able to recognise among them and respond accordingly is fundamental for plant survival and reproduction. Defence priming prepares the plant to better or more rapidly respond to future damage; however, while it is considered an adaptive trait, to date, no studies have evaluated the extent and specificity of the priming recognition. To estimate the costs, benefits and specificity of priming, we used a highly specialist plant-insect system (Datura stramonium-Lema daturaphila) and performed a reciprocal transplant experiment with two populations where a priming stimulus (sympatric vs. allopatric) and a damage treatment (sympatric) were applied. We found no evidence of a fitness cost of priming, given that primed plants without damage showed no reduction in fitness. In contrast, our treatments affected the probability of bud abortion. That is, when damaged plants received no priming or the priming came from an allopatric insect, the likelihood of aborting the first bud was 1.9 times greater compared to plants being primed by their sympatric insect. We also found that damaged plants primed with an allopatric insect produced 14% fewer seeds compared to plants receiving a sympatric priming stimulus. Tolerance to herbivore damage was also the lowest when plants received the priming stimulus from an allopatric insect. Overall, these results suggest that, in our study system, plants recognise their local insect population reducing the negative effect of damage through a tolerance response.

16.
Eur J Neurosci ; 56(6): 4788-4802, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35971965

RESUMO

We examined the behavioural responses and Fos expression pattern of rats that were exposed to snake threats from shed snakeskin and a live snake. We differentiated the behavioural responses and the pattern of Fos expression in response to the odour cues and mild threat from a live snake. Animals exposed to the snake odour alone or to the confined snake showed a great deal of risk assessment. Conversely, the intensification of odour during exposure to the live snake decreased the threat ambiguity, and the animals froze for a significantly longer period. Our Fos analysis showed that a pathway formed by the posteroventral part of the medial amygdalar nucleus to the central part of the ventromedial hypothalamic nucleus appeared to be solely responsive to odour cues. In addition, we showed increased Fos expression in a parallel circuit comprising the lateral amygdalar nucleus, ventral subiculum, lateral septum, and juxtadorsomedial region of the lateral hypothalamic area that is responsive to both the odour and mild threat from a live snake. This path is likely to process the environmental boundaries of the threat to be avoided. Both paths merge into the dorsal premammillary nucleus and periaqueductal grey sites, which all increase Fos expression in response to the snake threats and are likely to organize the defensive responses. Moreover, we found that the snake threat mobilized the Edinger-Westphal and supraoculomotor nuclei, which are involved in stress adaptation and attentional mechanisms.


Assuntos
Complexo Nuclear Basolateral da Amígdala , Comportamento Animal , Animais , Complexo Nuclear Basolateral da Amígdala/metabolismo , Comportamento Animal/fisiologia , Medo/fisiologia , Substância Cinzenta Periaquedutal/fisiologia , Proteínas Proto-Oncogênicas c-fos/metabolismo , Ratos , Serpentes/metabolismo
17.
Proc Biol Sci ; 289(1976): 20220799, 2022 06 08.
Artigo em Inglês | MEDLINE | ID: mdl-35703050

RESUMO

In nature, confrontations between conspecifics are recurrent and related, in general, due to the lack of resources such as food and territory. Adequate defence against a conspecific aggressor is essential for the individual's survival and the group integrity. However, repeated social defeat is a significant stressor promoting several behavioural changes, including social defence per se. What would be the neural basis of these behavioural changes? To build new hypotheses about this, we here investigate the effects of repeated social stress on the neural circuitry underlying motivated social defence behaviour in male mice. We observed that animals re-exposed to the aggressor three times spent more time in passive defence during the last exposure than in the first one. These animals also show less activation of the amygdalar and hypothalamic nuclei related to the processing of conspecific cues. In turn, we found no changes in the activation of the hypothalamic dorsal pre-mammillary nucleus (PMD) that is essential for passive defence. Therefore, our data suggest that the balance between the activity of circuits related to conspecific processing and the PMD determines the pattern of social defence behaviour. Changes in this balance may be the basis of the adaptations in social defence after repeated social defeat.


Assuntos
Comportamento Animal , Comportamento Social , Tonsila do Cerebelo/fisiologia , Animais , Comportamento Animal/fisiologia , Encéfalo , Hipotálamo , Masculino , Camundongos , Estresse Psicológico
18.
Cad. Ibero-Am. Direito Sanit. (Online) ; 11(1): 144-162, jan.-mar.2022.
Artigo em Português | LILACS-Express | LILACS | ID: biblio-1361510

RESUMO

Objetivo: analisar o papel das organizações de pacientes (OPs) e seus modos de atuação, quanto à implementação de direitos nos cuidados em saúde. Metodologia: tratou-se de pesquisa teórica e documental, realizada a partir do levantamento de literatura especializada nas bases de dados Google Scholar e SciELO, utilizando os descritores organização de pacientes, patient organizations e organizaciones de pacientes. Enquanto recorte de pesquisa, foram analisados os artigos sobre OPs. Complementarmente, foram utilizados o Relatório da União Europeia sobre os Direitos dos Pacientes e o documento do Fórum Europeu de Pacientes sobre OPs. Resultados: após análise prévia, selecionamos 28 artigos científicos que tratavam direta ou indiretamente da temática do artigo. Os documentos e artigos selecionados possibilitaram analisar o papel e o modo de atuação das OPs quanto à implementação de direitos nos cuidados em saúde. Conclusões: concluiu-se que é preciso ampliar o espectro de participação social das OPs na direção da luta pelos direitos dos pacientes, transformando-a numa prática não setorial e incidente em todos os níveis de cuidado, acarretando melhores resultados na saúde.


Objective: to analyze the role of patient organizations (POs) and their modes of action regarding the implementation of rights in health care. Methodology: it is a theoretical and documentary research, carried out based on the survey of specialized literature in Google Scholar and SciELO databases, using the descriptors organização de pacientes, patient organizations e organizaciones de pacientes. As a research focus, articles on POs were analyzed. In addition, the European Union Report on Patients' Rights and the European Patients' Forum document on POs were used. Results: after prior analysis, we selected 28 scientific articles that dealt directly or indirectly with the subject of the article. The documents and articles selected made it possible to analyze the role and mode of action of POs regarding the implementation of rights in health care. Conclusions: it was concluded that it is necessary to broaden the spectrum of social participation of POs towards the fight for patients' rights, transforming it into a non-sectoral practice that is incident at all levels of care, resulting in better health outcomes.


Objetivo: analizar el papel de las organizaciones de pacientes (OPs) y sus modos de actuación frente a la implementación de los derechos en los cuidados de salud. Metodología: se trata de una investigación teórica y documental, realizada a partir del levantamiento de literatura especializada en las bases de datos Google Scholar y SciELO, utilizando los descriptores organização de pacientes, patient organizations e organizaciones de pacientes. Como recorte de investigación, se analizaron artículos sobre PB. Además, se utilizaron el Informe de la Unión Europea sobre los Derechos de los Pacientes y el documento del Foro Europeo de Pacientes sobre OPs. Resultados: después un análisis previo, se seleccionaron 28 artículos científicos que trataran directa o indirectamente del tema del artículo. Los documentos y artículos seleccionados permitieron analizar el papel y el modo de actuación de las OPs frente a la implementación de los derechos en salud. Conclusiones: se concluyó que es necesario ampliar el espectro de participación social de las OPs hacia la lucha por los derechos de los pacientes, transformándola en una práctica no sectorial e incidente en todos los niveles de atención, redundando en mejores resultados en salud.

19.
Mem. Inst. Oswaldo Cruz ; 117: e210401, 2022. graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1365153

RESUMO

Chagas disease and leishmaniasis are neglected tropical diseases caused by the protozoan parasites Trypanosoma cruzi and Leishmania spp., respectively. They are among the most important parasitic diseases, affecting millions of people worldwide, being a considerable global challenge. However, there is no human vaccine available against T. cruzi and Leishmania infections, and their control is based mainly on chemotherapy. Treatments for Chagas disease and leishmaniasis have multiple limitations, mainly due to the high toxicity of the available drugs, long-term treatment protocols, and the occurrence of drug-resistant parasite strains. In the case of Chagas disease, there is still the problem of low cure rates in the chronic stage of the disease. Therefore, new therapeutic agents and novel targets for drug development are urgently needed. Antioxidant defence in Trypanosomatidae is a potential target for chemotherapy because the organisms present a unique mechanism for trypanothione-dependent detoxification of peroxides, which differs from that found in vertebrates. Cellular thiol redox homeostasis is maintained by the biosynthesis and reduction of trypanothione, involving different enzymes that act in concert. This study provides an overview of the antioxidant defence focusing on iron superoxide dismutase A, tryparedoxin peroxidase, and ascorbate peroxidase and how the enzymes play an important role in the defence against oxidative stress and their involvement in drug resistance mechanisms in T. cruzi and Leishmania spp.

20.
Ann Bot ; 127(7): 887-902, 2021 06 24.
Artigo em Inglês | MEDLINE | ID: mdl-33675229

RESUMO

BACKGROUND AND AIMS: We investigate patterns of evolution of genome size across a morphologically and ecologically diverse clade of Brassicaceae, in relation to ecological and life history traits. While numerous hypotheses have been put forward regarding autecological and environmental factors that could favour small vs. large genomes, a challenge in understanding genome size evolution in plants is that many hypothesized selective agents are intercorrelated. METHODS: We contribute genome size estimates for 47 species of Streptanthus Nutt. and close relatives, and take advantage of many data collections for this group to assemble data on climate, life history, soil affinity and composition, geographic range and plant secondary chemistry to identify simultaneous correlates of variation in genome size in an evolutionary framework. We assess models of evolution across clades and use phylogenetically informed analyses as well as model selection and information criteria approaches to identify variables that can best explain genome size variation in this clade. KEY RESULTS: We find differences in genome size and heterogeneity in its rate of evolution across subclades of Streptanthus and close relatives. We show that clade-wide genome size is positively associated with climate seasonality and glucosinolate compounds. Model selection and information criteria approaches identify a best model that includes temperature seasonality and fraction of aliphatic glucosinolates, suggesting a possible role for genome size in climatic adaptation or a role for biotic interactions in shaping the evolution of genome size. We find no evidence supporting hypotheses of life history, range size or soil nutrients as forces shaping genome size in this system. CONCLUSIONS: Our findings suggest climate seasonality and biotic interactions as potential forces shaping the evolution of genome size and highlight the importance of evaluating multiple factors in the context of phylogeny to understand the effect of possible selective agents on genome size.


Assuntos
Glucosinolatos , Mostardeira , Evolução Biológica , Tamanho do Genoma , Nutrientes , Filogenia , Solo
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