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2.
Sci Rep ; 14(1): 12223, 2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38806519

RESUMO

The Gouy phase is essential for accurately describing various wave phenomena, ranging from classical electromagnetic waves to matter waves and quantum optics. In this work, we employ phase-space methods based on the cross-Wigner transformation to analyze spatial and temporal interference in the evolution of matter waves characterized initially by a correlated Gaussian wave packet. First, we consider the cross-Wigner of the initial wave function with its free evolution, and second for the evolution through a double-slit arrangement. Different from the wave function which acquires a global Gouy phase, we find that the cross-Wigner acquires a Gouy phase difference due to different evolution times. The results suggest that temporal like-Gouy phase difference is important for an accurate description of temporal interference. Furthermore, we propose a technique based on the Wigner function to reconstruct the cross-Wigner from the spatial intensity interference term in a double-slit experiment with matter waves.

3.
J Ethnopharmacol ; 328: 118028, 2024 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-38492792

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Species of Vismia (Hypericaceae), known in Brazil as "lacre", are commonly used in traditional Amazonian medicine for the treatment of skin lesions, including those caused by Leishmania infection. AIM OF THE STUDY: Hexane extracts from the leaves of Vismia cayennensis, V. gracilis, V. sandwithii and V. guianensis, as well as from the fruits of the latter, in addition to the anthraquinones vismiaquinone, physcion and chrysophanol isolated from these species were explored for their anti-promastigote and anti-amastigote activity on Leishmania amazonensis. MATERIALS AND METHODS: Extracts were prepared by static maceration with n-hexane. The compounds, isolated by chromatographic techniques, were identified by spectroscopic methods (1H and 13C NMR). Promastigotes of L.amazonensis were incubated with hexane extracts (1-50 µg/mL) or anthraquinones (1-50 µM) and the parasite survival analyzed. The action of compounds on reactive oxygen species (ROS) production, mitochondrial membrane potential, and membrane integrity of promastigotes were evaluated by flow cytometer, and the cytotoxicity on mammalian cells using MTT assay. Furthermore, the activity of compounds against amastigotes and nitric oxide production were also investigated. RESULTS: Vismiaquinone and physcion were obtained from the leaves of V. guianensis. Physcion, as well as chrysophanol, were isolated from V. sandwithii. Vismia cayennensis and V. gracilis also showed vismiaquinone, compound detected in lower quantity in the fruits of V. guianensis. All extracts were active against the parasite, corroborating the popular use. The greatest activity against promastigotes was achieved with V. guianensis extract (IC50 4.3 µg/mL), precisely the most used Vismia species for treating cutaneous leishmaniasis. Vismiaquinone and physcion exhibited relevant activity with IC50 12.6 and 2.6 µM, respectively. Moreover, all extracts and anthraquinones tested induced ROS production, mitochondrial dysfunction, membrane disruption and were able to kill intracellular amastigote forms, being worthy of further in vivo studies as potential antileishmanial drugs. CONCLUSIONS: The overall data achieved in the current investigation scientifically validate the traditional use of Vismia species, mainly V. guianensis, as an anti-Leishmania agent. Furthermore, the promising results presented here indicate species of Vismia as potentially useful resources of Brazilian flora for the discovery of therapeutic solutions for neglected diseases.


Assuntos
Antiprotozoários , Clusiaceae , Emodina/análogos & derivados , Leishmaniose Cutânea , Leishmaniose , Plantas Medicinais , Animais , Camundongos , Hexanos , Espécies Reativas de Oxigênio , Antraquinonas/farmacologia , Antraquinonas/uso terapêutico , Leishmaniose Cutânea/tratamento farmacológico , Leishmaniose/tratamento farmacológico , Camundongos Endogâmicos BALB C , Mamíferos
4.
Front Cardiovasc Med ; 11: 1342832, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38450375

RESUMO

Introduction: Studies in cholesterol-fed rabbits showed that anti-proliferative chemotherapeutic agents such as paclitaxel associated with solid lipid nanoparticles (LDE) have marked anti-atherosclerotic effects. In addition, association with LDE nearly abolishes paclitaxel toxicity. We investigated whether treatment with LDE-paclitaxel changes plaque progression by coronary CT angiography and is safe in patients with chronic coronary artery disease. Methods: We conducted a prospective, randomized, double-blind, placebo-controlled pilot study in patients with multi-vessel chronic coronary artery disease. Patients were randomized to receive IV infusions of LDE-paclitaxel (paclitaxel dose: 175 mg/m2 body surface) or LDE alone (placebo group), administered every 3 weeks for 18 weeks. All participants received guideline-directed medical therapy. Clinical and laboratory safety evaluations were made at baseline and every 3 weeks until the end of the study. Analysis of inflammatory biomarkers and coronary CTA was also performed at baseline and 4 weeks after treatment. Results: Forty patients aged 65.6 ± 8 years, 20 in LDE-paclitaxel and 20 in placebo group were enrolled. Among those, 58% had diabetes, 50% had myocardial infarction, and 91% were in use of statin and aspirin. Baseline demographics, risk factors, and laboratory results were not different between groups. In all patients, no clinical or laboratory toxicities were observed. From the baseline to the end of follow-up, there was a non-significant trend toward a decrease in IL-6 levels and hsCRP in the LDE-paclitaxel group (-16% and -28%, respectively), not observed in placebo. Regarding plaque progression analysis, variation in plaque parameter values was wide, and no difference between groups was observed. Conclusion: In patients with multivessel chronic coronary artery disease and optimized medical therapy, LDE-paclitaxel was safe and showed clues of potential benefits in reducing inflammatory biomarkers. Clinical Trial Registration: https://clinicaltrials.gov/study/NCT04148833, identifier (NCT04148833).

5.
Opt Lett ; 48(12): 3323-3326, 2023 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-37319092

RESUMO

We report the enhancement of quantum correlations for biphotons generated via spontaneous four-wave mixing in an ensemble of cold two-level atoms. This enhancement is based on the filtering of the Rayleigh linear component of the spectrum of the two emitted photons, favoring the quantum-correlated sidebands reaching the detectors. We provide direct measurements of the unfiltered spectrum presenting its usual triplet structure, with Rayleigh central components accompanied by two peaks symmetrically located at the detuning of the excitation laser with respect to the atomic resonance. The filtering of the central component results in a violation of the Cauchy-Schwarz inequality to (4.8±1.0)≰1 for a detuning of 60 times the atomic linewidth, representing an enhancement by a factor of four compared with the unfiltered quantum correlations observed at the same conditions.

6.
Preprint em Português | SciELO Preprints | ID: pps-6086

RESUMO

The São Luís Island, Maranhão State, is an ecotonal region, a mix of humid forest, cocais forest, dune vegetation, restingas and mangroves. Unlike the interior of the State, their coastal areas have a gap in knowledge of the Passifloraceae. Here, through field expeditions and herbaria visit, we provide taxonomic treatment, identification key and comments on the Passifloraceae of the São Luís Island. Ten species were recorded: Passiflora auriculata Kunth, P. edulis Sims, P. foetida L., P. glandulosa Cav., P. laurifolia L., P. misera Kunth, P. nitida Kunth, P. picturata Ker Gawl., P. subrotunda Mast., and P. vespertilio L. Passiflora picturata and P. misera were recorded for the first time on São Luís Island.


A Ilha de São Luís, Estado do Maranhão, configura-se como uma região ecotonal, um misto de floresta úmida, mata-de-cocais, vegetação de dunas, restingas e manguezais. Diferentemente do interior do Estado do Maranhão, suas zonas costeiras possuem uma lacuna sobre o conhecimento da família Passifloraceae. Aqui, por meio de expedições de campo e consulta a herbários, nós fornecemos o tratamento taxonômico, chave de identificação e comentários sobre as Passifloraceae da Ilha de São Luís. Foram registradas dez espécies: Passiflora auriculata Kunth, P. edulis Sims, P. foetida L., P. glandulosa Cav., P. laurifolia L., P. misera Kunth, P. nitida Kunth, P. picturata Ker Gawl., P. subrotunda Mast. e P. vespertilio L. As espécies P. picturata e P. misera foram registradas pela primeira vez na Ilha de São Luís.

7.
Rev. bras. educ. méd ; 47(2): e055, 2023.
Artigo em Português | LILACS-Express | LILACS | ID: biblio-1449614

RESUMO

Resumo: Introdução: As Diretrizes Curriculares Nacionais (DCN) constituem as direções para formação do currículo de um curso. As DCN do curso médico atual foram instituídas há quase uma década. Nesse período, o mundo passou por mudanças sem precedentes, e a educação médica não pode ficar para trás. Desenvolvimento: O ensino médico no Brasil teve nos últimos 100 anos três principais modelos de ensino: desde o flexneriano, passando pela Problem-Based Learning (PBL), até o atual ensino baseado em competências. O entendimento de que o aluno é o centro do processo ensino aprendizagem já está enfatizado nas DCN de 2014, mas será que esse conceito está sendo implementado na prática das instituições de ensino superior? Como as DCN podem ajudar a guiar de forma mais clara e efetiva uma formação médica que vá além do conhecimento técnico e lapidar um profissional humanizado, ético e com olhar para o indivíduo e para a comunidade? Será que precisaremos "reprogramar" o Global Positioning System (GPS), a rota, das DCN depois de enfrentarmos tantas mudanças decorrentes da pandemia da Covid-19? Conclusão: Apesar dos desafios, há crescente envolvimento do corpo docente das instituições de ensino superior nas melhorias necessárias para a formação médica atual.


Abstract: Introduction: The National Curriculum Guidelines (NCG) provide the directions which an undergraduate course must follow. The current NCGs for the medical course were established almost a decade ago. In this period, the world has undergone unprecedented changes and medical education cannot be left behind. Development: Medical education in Brazil has been based on three main models in the last one hundred years: the Flexnerian, Problem-Based Learning (PBL), and the current competency-based learning. The concept that the student is the center of the teaching-learning process was already emphasized in the 2014 NCG, but is this actually implemented in practice by the universities? How can the NCG help guide a more clear and effective medical education that goes beyond technical knowledge and shapes a humanized ethical professional who views the needs of both the individual and the community? Is it necessary to reroute the GPS of the NCG after so many changes caused by the Covid-19 pandemic? Conclusion: Despite the challenges faced, university faculties are increasing their involvement in implementing the changes required for today's medical education.

8.
Phys Rev Lett ; 128(8): 083601, 2022 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-35275643

RESUMO

We report the experimental verification of nonclassical correlations for an unfiltered spontaneous four-wave mixing process in an ensemble of cold two-level atoms, confirming theoretical predictions by Du et al. in 2007 for the violation of a Cauchy-Schwarz inequality in the system, and obtaining R=(1.98±0.03)≰1. Quantum correlations are observed in a nanoseconds timescale in the interference between the central exciting frequency and sidebands dislocated by the detuning to the atomic resonance. They prevail over the noise background coming from Rayleigh scattering from the same optical transition. These correlations are fragile with respect to processes that disturb the phase of the atomic excitation, but are robust to variations in number of atoms and to increasing light intensities.

9.
PeerJ ; 10: e12937, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35194527

RESUMO

We describe three new species of Malpighiaceae that are endemic to central Brazil and related to the Heteropterys pannosa complex, a group of xylopodiferous, unbranched subshrubs with fruit in mericarps that have a strongly reduced or no dorsal wing. Heteropterys tocantinensis is more common in eastern Tocantins State and on the border with Bahia State, and there are a few records from Mato Grosso State. Heteropterys veadeirensis is restricted to northern Goiás State and H. walteri has a wider distribution, occurring in some municipalities in northern Goiás and southern Tocantins. Additionally, we also provide detailed redescriptions of H. pannosa and H. rosmarinifolia, the two previously known species in this complex. All species are considered Endangered (EN) based on IUCN criteria, especially due to the low area of occupancy. Illustrations, distribution maps, and information about phenology and habitat are also provided for all taxa.


Assuntos
Malpighiaceae , Animais , Brasil , Ecossistema
10.
J Ethnopharmacol ; 284: 114745, 2022 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-34656665

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: The tribe Symphonieae (Clusiaceae) encompasses 48 species accommodated in seven genera (Lorostemon, Montrouziera, Moronobea, Pentadesma, Platonia, Symphonia and Thysanostemon). Parts of these plants, mainly the exudates and the seeds oil are useful for different purposes, especially for treating dermatological conditions. In addition to the role in the folk medicine, some species are of great economic and cultural importance for native people from different continents. AIM OF THE REVIEW: The goal of this review is to critically summarize the current knowledge on systematics, ethnobotanical, chemical and pharmacological aspects of species from the tribe Symphonieae, as well as to provide support for future taxonomic and phylogenetic studies on the Clusiaceae family. MATERIALS AND METHODS: The available information was gathered from many different databases (Web of Science, ScienceDirect, Scopus, Pubmed, ChemSpider, SciFinder, ACS Publications, Wiley Online Library, Useful Tropical Plants Database, Google Scholar). Additional data from books, theses and dissertations were also included in this review. RESULTS: Chemical studies of Symphonieae have demonstrated that the genera are a source of benzophenones, xanthones and biflavonoids. Components as sesquiterpenoids, triterpenoids, flavonoids, free fatty acids, among others, have also been reported. Extracts and compounds isolated from a variety of species have been exhibiting antimicrobial, cytotoxic and antiprotozoal activities, corroborating part of their medicinal uses. In addition, certain species produce edible fruits and a kind of "butter" with economic importance. All species produce exudate, which often has great relevance in the daily lives of local people. CONCLUSION: Several species of Symphonieae have potential therapeutic applications and some of them have been investigated to scientifically validate their popular uses. In addition, a number of species have proved to be a rich source of promising pharmacologically active compounds. Finally, the value of fruits, exudate and butter, for instance, should serve as a stimulus for the sustainable development of products that aim to take advantage of these natural resources.


Assuntos
Clusiaceae/química , Medicina Tradicional/métodos , Extratos Vegetais/farmacologia , Animais , Etnobotânica , Etnofarmacologia , Humanos , Compostos Fitoquímicos/química , Compostos Fitoquímicos/isolamento & purificação , Compostos Fitoquímicos/farmacologia , Extratos Vegetais/química
11.
PhytoKeys ; 181: 49-64, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34566447

RESUMO

Tovomitopsis Planch. & Triana is a Brazilian Atlantic Forest endemic genus composed of two species: T.paniculata (Spreng.) Planch. & Triana and T.saldanhae Engl. An investigation was conducted to clarify the nomenclatural history of Tovomitopsis. We report the results of this investigation, provide an updated description of the genus, and propose lectotypes for T.paniculata and its synonyms: Tovomitafoliosa C.Presl and Tovomitapaniculata Cambess. We also propose lectotypes for T.saldanhae and for the new synonym Clusiaangustifolia Engl.

12.
Acta amaz ; 50(2): 149-154, abr - jun. 2020.
Artigo em Inglês | LILACS | ID: biblio-1118395

RESUMO

Although the number of recently described Tovomita species is relatively high, much more remains to be done, given that each new survey of representative Amazonian collections reveals many potentially undescribed taxa. In the treatment for Tovomita published in Flora of the Venezuelan Guayana, at least six distinct morphotypes did not match any previously described species. Here we recognize morphotype "D" as a new endemic species from Cerro de la Neblina. Additionally, we provide an identification key to the Tovomita species in Venezuela. (AU)


Assuntos
Ecossistema Amazônico , Clusiaceae , Venezuela
13.
Naturwissenschaften ; 107(3): 21, 2020 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-32378062

RESUMO

Reliable data are needed to produce representative and useful conservation assessments for species. To this end, taxonomists and their unpublished, archived and unused databases-here called phantom databases-have great relevance for assessing the conservation status of species. Taxonomist's phantom databases are usually the result of a review work, and, if made available, they could be used to assess a species conservation status with greater accuracy, allowing for more effective conservation planning. Here we characterise these databases, provide examples of their relevance and recommend solutions to make these phantom databases available for conservation use. Databases of taxonomic and geographic information need not be phantom and could be made openly accessible to encourage their use in conservation activities.


Assuntos
Classificação , Conservação dos Recursos Naturais/métodos , Bases de Dados como Assunto/normas , Disseminação de Informação , Conservação dos Recursos Naturais/tendências , Bases de Dados como Assunto/tendências
14.
Mol Phylogenet Evol ; 134: 142-151, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30743062

RESUMO

Clusieae is an exclusively Neotropical tribe in the family Clusiaceae sensu stricto. Although tribes within Clusiaceae are morphologically and phylogenetically well-delimited, resolution among genera within these tribes remains elusive. The tribe Clusieae includes an estimated ∼500 species distributed among five genera: Chrysochlamys, Clusia, Dystovomita, Tovomita, and Tovomitopsis. In this study, we used nearly complete plastid genomes from 30 exemplar Clusieae species representing all genera recognized, plus two outgroups to infer the phylogeny of the tribe using Maximum Likelihood and Bayesian Inference. For comparison, we also inferred a phylogeny from the nuclear Internal Transcribed Spacer (ITS) region using the same methods. Our study corroborates earlier findings that Clusia is monophyletic while Tovomita is not. It also provides additional support to the hypothesis that Chrysochlamys and Tovomitopsis are not closely related despite gross morphological similarity. Tovomita is divided into three distantly related clades: (i) core Tovomita (including the type T. guianensis), (ii) T. croatii, and (iii) the T. weddelliana species complex. Members of the T. weddelliana complex are isolated from the core Tovomita, and placed in a well-supported clade that is sister to a clade composed of Chrysochlamys plus Clusia. Tovomita croatii is nested within Chrysochlamys. We propose taxonomic revisions to accommodate our phylogenetic findings, including the description of the new genus Arawakia, which includes the 18 species formerly recognized in the T. weddelliana species complex. Lectotypes are also designated for nine species (i.e., Arawakia angustata, A. lanceolata, A. lingulata, A. longicuneata, A. macrocarpa, A. oblanceolata, A. pithecobia, A. rhizophoroides, and A. weddelliana), and a taxonomic key for the identification of the six genera of Clusieae recognized is presented.


Assuntos
Clusiaceae/genética , Genomas de Plastídeos , Teorema de Bayes , Clusiaceae/anatomia & histologia , Flores/anatomia & histologia , Frutas/anatomia & histologia , Funções Verossimilhança , Filogenia
15.
Eur J Pharmacol ; 833: 425-431, 2018 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-29913125

RESUMO

The purpose of this study was to evaluate in vitro the effect of the combination of BRL 37344 (ß3-adrenoceptor agonist) with tadalafil (phosphodiesterase type 5 inhibitor) or rolipram (phosphodiesterase type 4 inhibitor) in an experimental model of detrusor overactivity. The experiments were carried out in two phases using bladder strips of mice. In the first phase, on the top of 40 mM potassium-induced contraction, strips isolated from control mice were exposed to increasing concentrations of each study drug. In another series of experiments, prior to contraction, strips were incubated with either tadalafil or rolipram, followed by the addition of increasing concentrations of BRL 37344. In the second phase, the same protocols were performed with animals previously treated with L-NAME for 30 days. Chronic L-NAME administration leads to detrusor overactivity due to nitric oxide synthase inhibition. In phase one, preincubation with tadalafil enhanced relaxation response to BRL 37344 at two concentrations. Pretreatment with rolipram had no effect on BRL 37344-induced relaxation. In L-NAME-treated mice, rolipram induced more relaxation than the other drugs, enhancing relaxation response to BRL 37344 at almost all concentrations, but no synergistic effect with tadalafil was observed. The relaxant effect of BRL 37344 was enhanced by rolipram but not by tadalafil, suggesting that PDE4 inhibition, especially when associated with ß3-adrenoceptor stimulation, could represent a potential treatment for overactive bladder.


Assuntos
Agonistas de Receptores Adrenérgicos beta 3/farmacologia , Inibidores da Fosfodiesterase 4/farmacologia , Inibidores da Fosfodiesterase 5/farmacologia , Bexiga Urinária Hiperativa/tratamento farmacológico , Agonistas de Receptores Adrenérgicos beta 3/uso terapêutico , Animais , Modelos Animais de Doenças , Avaliação Pré-Clínica de Medicamentos , Sinergismo Farmacológico , Quimioterapia Combinada/métodos , Etanolaminas/farmacologia , Etanolaminas/uso terapêutico , Humanos , Masculino , Camundongos , Contração Muscular/efeitos dos fármacos , Relaxamento Muscular/efeitos dos fármacos , Músculo Liso/fisiopatologia , NG-Nitroarginina Metil Éster/toxicidade , Inibidores da Fosfodiesterase 4/uso terapêutico , Inibidores da Fosfodiesterase 5/uso terapêutico , Rolipram/farmacologia , Rolipram/uso terapêutico , Tadalafila/farmacologia , Tadalafila/uso terapêutico , Resultado do Tratamento , Bexiga Urinária/efeitos dos fármacos , Bexiga Urinária/fisiopatologia , Bexiga Urinária Hiperativa/induzido quimicamente , Bexiga Urinária Hiperativa/fisiopatologia
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