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1.
J Environ Manage ; 367: 121752, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39067341

RESUMO

Sustainable management of the Amazon rainforest is fundamental for supporting life on earth because of its crucial role in sequestering carbon. One of the species grown in the forest is açaí (Euterpe oleracea), which is an important food and income source for its inhabitant. The acai seed, resulting from the processing of the fruit, is a solid organic residue, which has been an agent of undesirable environmental impacts such as natural landscape modifications, clogging sewers and water courses, eutrophication of surface waters. In this research, we evaluated the use of wood chips as a source of energy in a rustic oven to produce acai biochar so that family farmers carry out sustainable management of the residue and use biochar to improve soil quality and produce seedlings of native plants to regenerate degraded forests. The experiment was conducted in Pará, Brazil, Amazon region, using a randomized complete block design. A factorial treatment structure was implemented consisting of four biochar particle sizes (3, 5, 7, and 12 mm), 4 application rates (4, 8, 16, and 32 t ha-1), and a biochar-free control, with 5 replications. The results showed that the methodology for biochar production was easy to apply and low cost, allowing its use by family farmers. The combination of biochar rate and particle size affected soil properties and the development of black pepper seedlings in different ways. The soil properties affected were water retention capacity, moisture, fluorescein diacetate hydrolysis and arylsulphatase activity. The growth parameters of the affected black pepper seedlings were height and root system development.


Assuntos
Carvão Vegetal , Plântula , Sementes , Solo , Solo/química , Plântula/crescimento & desenvolvimento , Sementes/crescimento & desenvolvimento , Brasil , Piper nigrum
2.
J Phys Chem A ; 128(28): 5586-5604, 2024 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-38954748

RESUMO

High-level electronic structure calculations were conducted to examine the bonding and spectroscopic properties of the UO0/± and UF0/± diatomic molecules. The low-lying Ω states were described by using multireference SO-CASPT2 calculations. The adiabatic electronic affinity (AEA), adiabatic ionization energy (IE), and bond dissociation energy (BDE) were calculated at the Feller-Peterson-Dixon (FPD) level. The ground state of UO is predicted to be 5I4, and that of UF is 4I9/2. The calculated AEAs of UO and UF are 1.123 and 0.453 eV, respectively, and the corresponding IEs are 5.976 and 6.278 eV. The BDE of UO (749.5 kJ/mol) is predicted to be considerably higher than that of UF (627.2 kJ/mol), and both are higher than those predicted for UB, UC, and UN. NBO calculations show strong ionic character for the ground states of UO and UF and bond orders that range from 2 to 3 and from 1 to 2, respectively. Comparisons of the calculated properties to those of the series comprising UB, UC, and UN diatomic molecules are given.

3.
Curr Microbiol ; 81(8): 256, 2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38955831

RESUMO

Antimicrobial resistance is a global health issue, in which microorganisms develop resistance to antimicrobial drugs, making infections more difficult to treat. This threatens the effectiveness of standard medical treatments and necessitates the urgent development of new strategies to combat resistant microbes. Studies have increasingly explored natural sources of new antimicrobial agents that harness the rich diversity of compounds found in plant species. This pursuit holds promise for the discovery of novel treatments for combating antimicrobial resistance. In this context, the chemical composition, antibacterial, and antibiofilm activities of the essential oil from Croton urticifolius Lam. leaves (CuEO) were evaluated. CuEO was extracted via hydrodistillation, and its chemical constituents were identified via gas chromatography-mass spectrometry (GC/MS). The antibacterial activity of CuEO was evaluated in a 96-well plate via the microdilution method, and the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) values were determined. The effect of CuEO on biofilm formation was assessed by quantifying the biomass using crystal violet staining and viable cell counting. In addition, alterations in the cellular morphology of biofilms treated with CuEO were examined using scanning electron microscopy (SEM) and laser confocal microscopy. GC/MS analysis identified 26 compounds, with elemicine (39.72%); eucalyptol (19.03%), E-caryophyllene (5.36%), and methyleugenol (4.12%) as the major compounds. In terms of antibacterial activity, CuEO showed bacteriostatic effects against Staphylococcus aureus ATCC 700698, S. aureus ATCC 25923, Staphylococcus epidermidis ATCC 12228, and Escherichia coli ATCC 11303, and bactericidal activity against S. aureus ATCC 700698. In addition, CuEO significantly inhibited bacterial biofilm formation. Microscopic analysis showed that CuEO damaged the bacterial membrane by leaching out the cytoplasmic content. Therefore, the results of this study show that the essential oil of C. urticifolius may be a promising natural alternative for preventing infections caused by bacterial biofilms. This study is the first to report the antibiofilm activity of C. urticifolius essential oil.


Assuntos
Antibacterianos , Biofilmes , Croton , Testes de Sensibilidade Microbiana , Óleos Voláteis , Folhas de Planta , Biofilmes/efeitos dos fármacos , Óleos Voláteis/farmacologia , Óleos Voláteis/química , Croton/química , Antibacterianos/farmacologia , Antibacterianos/química , Folhas de Planta/química , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/fisiologia , Cromatografia Gasosa-Espectrometria de Massas , Extratos Vegetais/farmacologia , Extratos Vegetais/química , Membrana Celular/efeitos dos fármacos
4.
J Oral Biol Craniofac Res ; 14(3): 326-334, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38660054

RESUMO

Objective: to present a 12-month follow-up with photographic and tomographic analyses of the effect of polymethyl methacrylate-based bone cement graft (PMMA) in gingival exposure (GE) in patients with excessive gingival display (EGD). Methods: Twelve patients with EGD were included. The PMMA was surgically placed. A frontal and lateral photograph protocol was performed at baseline (T0), 3 (T3), 6 (T6), and 12 months (T12) post-operatively. Soft tissue cone-beam computed tomography (ST-CBCT) was performed at T0 and T12. Measures included GE, length of the lip vermilion (LLV), lip shape (LS), nose width (NW), filter width (FW), nasolabial angle (NAS) while smiling, and nasolabial angle at rest (NAR). The height, thickness, and volume of the cement graft were also measured in the ST-CBCT. The comparisons were performed by Kruskal-Wallis test at 5 % of significance (p < 0.05). Results: The height, thickness, and volume of the PMMA were respectively 12.84 ± 1.59 mm, 3.83 ± 0.53, and 1532.02 ± 532.52 mm3. PMMA significantly decreased GE from 8.33 ± 1.25 mm (T0) to 6.60 ± 0.93 mm (T12) (p < 0.01). NAR was 98.34 ± 9.28° at T0 and increased to 105.13 ± 7.33° at T12; however, the angle value was not statistically different (p = 0.08). LLV, LS, NW, FW, and NAS did not exhibit statistical differences between the baseline and follow-up periods. Conclusions: PMMA significantly decreased GE in a 12-month follow-up without influencing adjacent soft tissue anatomical structures.

5.
Chemosphere ; 354: 141722, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38494004

RESUMO

Nickel (Ni) is an essential element, but it can be phytotoxic in high concentration, which may be caused by high availability in soil solution. The objective of this study was to evaluate the effect of sources and doses of Ni applied to a dystrophic Red Latosol cultivated with sorghum on i) the availability of the metal in the soil; ii) the impact on biological and biochemical properties of the soil; iii) the absorption and distribution in sorghum plants; and iv) crop productivity. The experiment was carried out within a completely randomized design with two nickel sources [nickel(II) nitrate, Ni(NO3)2 and nickel(III) oxide, Ni2O3], three doses (35, 70, and 140 mg Ni kg-1 soil), plus controls without Ni, with 3 replications. The concentrations of Ni in the soil, soil microbial biomass (SMB), basal soil respiration (BSR), metabolic quotient (qCO2), fluorescein diacetate (FDA) hydrolysis, and urease activity were determined. The concentrations of Ni in the leaf diagnostic and in the plant (shoot, root, and grains) were also measured. In the soil, the concentrations of available Ni remained between 0.21 and 54.01 mg Ni kg-1. Ni2O3 contributed very little to the increase in available Ni. SMB and the FDA hydrolysis were not affected by the Ni source or Ni dose, but BSR and qCO2 had significant increase with Ni application rates, suggesting the soil microorganisms faced stress. Soil urease activity was affected by Ni dose but not by Ni source. The dose of Ni as Ni(NO3)2 decreased the metal concentration in the plant, while that of Ni2O3 increased it. Nickel source did not affect dry mass production of the plants, but grain yield was affected in a dose-dependent manner when Ni2O3 was the source of Ni.


Assuntos
Poluentes do Solo , Sorghum , Poluentes do Solo/análise , Níquel/química , Sorghum/metabolismo , Solo/química , Urease/metabolismo , Plantas/metabolismo
6.
Clin Oral Investig ; 28(1): 76, 2024 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-38180519

RESUMO

OBJECTIVES: To evaluate the stability of periodontal tissues 3 (T3), 6 (T6), and 12 (T12) months after esthetic crown lengthening (ACL) and the possible correlations between changes in those structures. MATERIALS AND METHODS: Twenty individuals were evaluated through clinical assessment, photography, and tomography. Measurements included gingival margin (GM), clinical crown length (CCL), interdental papilla height (PH) and width (PW), gingival thickness (GT), bone thickness (BT), probing depth (PD), distance between alveolar crest and GM, distance between alveolar crest and cementoenamel junction. Nonparametric and correlation statistics were performed (p < 0.05). RESULTS: CCL at T0 was 7.42 ± 0.70 mm and increased to 9.48 ± 0.49 mm immediately after ACL, but it decreased to 8.93 ± 0.65 mm at T12. PD decreased 0.60 mm from T0 to T6, and it increased 0.39 mm from T6 to T12. BT decreased 0.20 mm, while GT increased 0.29 mm from T0 to T12. Both PW and PH showed enlargement in T12. A positive moderate correlation was found between CCL/T0 and CCL/T12, GT/T0 and AC-GM/T12, BT/T0 and GT/T12. A few negative moderate correlations were PD/T0 and CCL/T12, PD/T0 and PH/T0, PD/T0 and BT/T12. CONCLUSIONS: ACL procedure was effective. Although some rebound occurred, that was not clinically important. PD tended to reestablish its original length, partially due to a migration of GM during the healing period. Besides, a thickening of supracrestal soft tissues was observed. CLINICAL RELEVANCE: The present study centers on the factors influencing the stability of periodontal tissues after esthetic crown lengthening, underscoring the procedure's influence on esthetics and biology and the need for careful treatment planning.


Assuntos
Aumento da Coroa Clínica , Estética Dentária , Humanos , Gengiva , Periodonto , Processo Alveolar
7.
Demetra (Rio J.) ; 19: 71469, 2024. tab, ilus
Artigo em Inglês, Português | LILACS | ID: biblio-1552727

RESUMO

Introdução: Favelas são regiões que não foram priorizadas pelas políticas públicas, e isso se reflete no ambiente alimentar e, consequentemente, na dificuldade de acesso aos alimentos, sobretudo aqueles produzidos de forma sustentável. Objetivo: Caracterizar o acesso físico às feiras de orgânicos municipais em favelas de Belo Horizonte, Minas Gerais, identificando desertos e pântanos alimentares e realizando uma comparação com a disponibilidade, distância e tempo de deslocamento de estabelecimentos que ofertam alimentos convencionais nessas áreas. Métodos: Foi analisada a distribuição das feiras de orgânicos municipais, dos equipamentos públicos de segurança alimentar e nutricional e dos estabelecimentos que ofertam alimentos cadastrados na Secretaria da Fazenda do Estado de Minas Gerais para o ano de 2019, nos 192 setores censitários localizados em favelas de Belo Horizonte. Para as análises closestfacility e distância de deslocamento, foi utilizado o buffer network de 500 metros. Também foi realizada a análise do tempo de deslocamento utilizando transporte público. Resultados: As feiras de orgânicos municipais estão em menor número e mais distantes dos centroides das favelas. E, além da maior distância para acessar as feiras caminhando, acessá-las por meio de transporte público leva, em geral, um tempo maior de deslocamento. Conclusões: São necessários programas e políticas públicas que incentivem a abertura de feiras de orgânicos e outros tipos de estabelecimentos que ofertam alimentos in natura e minimamente processados que adotem modelos de produção sustentáveis em áreas de favelas, a fim de reduzir as iniquidades de acesso aos alimentos saudáveis e sustentáveis nesse território.Introdução: Favelas são regiões que não foram priorizadas pelas políticas públicas, e isso se reflete no ambiente alimentar e, consequentemente, na dificuldade de acesso aos alimentos, sobretudo aqueles produzidos de forma sustentável. Objetivo: Caracterizar o acesso físico às feiras de orgânicos municipais em favelas de Belo Horizonte, Minas Gerais, identificando desertos e pântanos alimentares e realizando uma comparação com a disponibilidade, distância e tempo de deslocamento de estabelecimentos que ofertam alimentos convencionais nessas áreas. Métodos: Foi analisada a distribuição das feiras de orgânicos municipais, dos equipamentos públicos de segurança alimentar e nutricional e dos estabelecimentos que ofertam alimentos cadastrados na Secretaria da Fazenda do Estado de Minas Gerais para o ano de 2019, nos 192 setores censitários localizados em favelas de Belo Horizonte. Para as análises closestfacility e distância de deslocamento, foi utilizado o buffer network de 500 metros. Também foi realizada a análise do tempo de deslocamento utilizando transporte público. Resultados: As feiras de orgânicos municipais estão em menor número e mais distantes dos centroides das favelas. E, além da maior distância para acessar as feiras caminhando, acessá-las por meio de transporte público leva, em geral, um tempo maior de deslocamento. Conclusões: São necessários programas e políticas públicas que incentivem a abertura de feiras de orgânicos e outros tipos de estabelecimentos que ofertam alimentos in natura e minimamente processados que adotem modelos de produção sustentáveis em áreas de favelas, a fim de reduzir as iniquidades de acesso aos alimentos saudáveis e sustentáveis nesse território.


Introduction: Favelas are usually in regions forgotten by public policies, and it reflects on their residents' food environment, as well as on their tough time accessing food, mainly produced through sustainable ways. Objective: Featuring the physical access to municipal organic-food fairs in Belo Horizonte City, Minas Gerais State, based on identifying food deserts and swamps and comparing food availability to distance and displacement time from shops that sell conventional food in these places. Methods: The distribution of organic food municipal fairs, as well as of both food security and nutrition public equipment, and shops selling food that was registered at Minas Gerais State Treasure Secretariat in 2019, located in the 192 census sectors set in Belo Horizonte favelas. The closest facility and displacement distance analyses were based on the 500m buffer network. Displacement time linked to public transportation usage was also analyzed. Results: The number of organic food municipal fairs in favelas is smaller, and favelas are located farther from fairs' centroids. The distance to be crossed to get to fairs on foot in favelas is also longer, and getting to them by public transportation often demands longer displacements. Conclusions: Public programs and policies are needed to encourage new organic fairs and other establishment types capable of providing fresh and minimally processed food in favela areas based on sustainable production models. It must be done to reduce inequities in access to healthy and sustainable food in these territories.


Assuntos
Acessibilidade Arquitetônica , Áreas de Pobreza , Alimentos Orgânicos , Dieta Saudável , Abastecimento de Alimentos , Acesso a Alimentos Saudáveis , Brasil
8.
Mol Brain ; 16(1): 64, 2023 08 21.
Artigo em Inglês | MEDLINE | ID: mdl-37605272

RESUMO

The insula and anterior cingulate cortex (ACC) are brain regions that undergo structural and functional reorganization in neuropathic pain states. Here, we aimed to study inhibitory parvalbumin positive (PV+) posterior insula (pIC) to posterior ACC (pACC) projections, and to evaluate the effects of direct optogenetic manipulation of such projections on mechanical nociception and spontaneous ongoing pain in mice with Spared Nerve Injury (SNI). CTB488 tract-tracing in male PVCrexAi9 mice revealed a small proportion of PV+ projections from the pIC to the pACC. Electrophysiological analysis confirmed the existence of synaptic inputs into the pACC by pIC GABAergic cells. Optogenetic stimulation of these pathways did not change mechanical nociception, but induced conditioned place preference behavior responses. Our results suggest the presence of inhibitory projections between the pIC and the pACC which are able to selectively modulate affective aspects of neuropathic pain.


Assuntos
Giro do Cíngulo , Neuralgia , Masculino , Animais , Camundongos , Condicionamento Clássico , Córtex Insular , Optogenética
9.
J Fungi (Basel) ; 9(7)2023 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-37504744

RESUMO

Multiresistant pathogens pose a serious threat to human health. The genus Candida is one class of human pathogenic yeasts responsible for infections affecting healthy and immunocompromised patients. In this context, plant essential oils emerged as a future natural alternative to control the diseases caused by these pathogens. Based on that, the present study aimed to evaluate the antimicrobial potential of essential oil from C. pluriglandulosus and understand the mechanism of action. Here, it highlighted antimicrobial activity and the mechanisms of action of the essential oil extracted from C. pluriglandulosus Carn.-Torres & Riina (CpEO) leaves on human pathogenic microorganisms in planktonic and biofilm lifestyles. In addition, for the first time, the oil composition was revealed by GC-MS analysis and the toxicity to human red blood cells (HRBC). Twenty-six chemical compounds were identified in CpEO, elemicin, bicyclogermacrene, caryophyllene, brevifolin, and 2,4,6-trimethoxy-styrene. Through hemolytic assay, it was shown that CpEO has no toxicity to human RBCs. At the concentration of 50 µg mL-1, CpEO did not show great antibacterial potential. However, promising data were found for C. krusei and C. parapsilosis inhibiting by 89.3% and 80.7% of planktonic cell growth and 83.5% and 77.9% the biofilm formation, respectively. Furthermore, the mechanisms of action CpEO were elucidated by fluorescence. Scanning electron microscopy revealed damage to the cell membrane and pore formation, ROS overproduction, and induction of apoptosis in candida cells. Our results reinforce the potential of CpEO as an effective alternative molecule of pharmaceutical interest.

10.
Angew Chem Int Ed Engl ; 62(39): e202307218, 2023 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-37438320

RESUMO

The purely chemical synthesis of fluorine is a spectacular reaction which for more than a century had been believed to be impossible. In 1986, it was finally experimentally achieved, but since then this important reaction has not been further studied and its detailed mechanism had been a mystery. The known thermal stability of MnF4 casts serious doubts on the originally proposed hypothesis that MnF4 is thermodynamically unstable and decomposes spontaneously to a lower manganese fluoride and F2 . This apparent discrepancy has now been resolved experimentally and by electronic structure calculations. It is shown that the reductive elimination of F2 requires a large excess of SbF5 and occurs in the last reaction step when in the intermediate [SbF6 ][MnF2 ][Sb2 F11 ] the addition of one more SbF5 molecule to the [SbF6 ]- anion generates a second tridentate [Sb2 F11 ]- anion. The two tridentate [Sb2 F11 ]- anions then provide six fluorine bridges to the Mn atom thereby facilitating the reductive elimination of the two fluorine ligands as F2 .

11.
Artigo em Português | LILACS | ID: biblio-1442381

RESUMO

Introdução: O diabete mellitus (DM) e a hipertensão arterial sistêmica (HAS) são doenças crônicas não-transmissíveis que se associam a alto risco de mortalidade. Objetivo: Analisar o perfil laboratorial de pessoas com DM e HAS acompanhados na atenção primária à saúde. Método: Estudo descritivo e transversal, com a amostra de 345 pessoas em acompanhamento pelas estratégias de saúde da família pertencentes a duas Unidades Básicas de Saúde da zona urbana do município de Santarém, Pará, Brasil. Os participantes foram divididos em quatro grupos conforme diagnóstico: HAS; DM; ambas (DM-HAS); ou nenhuma (SEM). Foram coletadas informações socioeconômicas e clínicas dos participantes, com posterior coleta de sangue para as variáveis bioquímicas. Para a análise de dados foi realizada a estatística descritiva e inferencial, adotando-se significância de p<0,05. Resultados: Em todos os grupos predominaram participantes do sexo feminino, casados, pardos, com renda até dois salários, com 4-7 anos de estudo, não tabagistas e não estilistas. Em relação ao SEM, o DM se associou com valores alterados para glicose (p<0,0001), HDL-c (p=0,0481), ureia (p=0,0252), creatinina (p=0,0006) e hemoglobina (p=0,0024). Já o DM-HAS se associou com a presença de alteração para glicose (p<0,0001), ureia (p=0,0009), creatinina (p=0,0059) e taxa de filtração glomerular (p=0,0048). Conclusão: Conclui-se, conforme o método proposto, que a presença da DM e/ou HAS são capazes de modificar o perfil bioquímico de maneira negativa, bem como se ressalta a importância do acompanhamento desta pessoa pela atenção primária à saúde, visto que algumas pessoas apresentaram alterações bioquímicas que chamam atenção e não estão em acompanhamento (AU).


Introduction:Diabetes mellitus (DM) and systemic arterial hypertension (SAH) are chronic non-communicable diseases that are associated with a high risk of mortality. Objective: To analyze the laboratory profile of people with DM and SAH followed up in primary health care. Methods: Descriptive and cross-sectional study, with a sample of 345 people being monitored by family health strategies belonging to two Basic Health Units in the urban area of the city of Santarém, Pará, Brazil. Participants were divided into four groups according to their diagnosis: SAH; DM; both (DM-SAH); or neither (NO). Socioeconomic and clinical information was collected from the participants, with subsequent blood collection for biochemical variables. Descriptive and inferential statistics were used for data analysis, adopting a significance of p<0.05. Results: In all groups, female participants, married, brown, with an income of up to two salaries, 4-7 years of schooling, non-smokers, and non-alcoholics predominated. Compared to NO, DM was associated with altered values for glucose (p<0.001), HDL-c (p=0.048), urea (p=0.025), creatinine (p<0.001), and hemoglobin (p=0.002). DM-SAH was associated with the presence of alterations in glucose (p<0.001), urea (p<0.001), creatinine (p=0.005), and glomerular filtration rate (p=0.004). Conclusion: In conclusion, the results using the proposed method indicate that the presence of DM and/or SAH is able to negatively modify the biochemical profile. In addition, the importance of monitoring this population in primary health care was demonstrated, since some people presented potentially worrying biochemical alterations that are not being followed up (AU).


Assuntos
Humanos , Atenção Primária à Saúde , Fenômenos Bioquímicos , Indicadores Básicos de Saúde , Diabetes Mellitus/diagnóstico , Hipertensão/diagnóstico
12.
J Phys Chem A ; 127(14): 3179-3189, 2023 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-36988907

RESUMO

High-level correlated molecular orbital theory calculations have been performed to predict the thermodynamic and electronic properties of diatomic NpH0/+/- and PuH0/+/-. The excited states up to ∼10,000 cm-1 were predicted for these molecules at the multireference SO-CASPT2 level. The inclusion of spin-orbit effects is fundamental to predict the low-lying state ordering. NpH is predicted to have a 5Π0 ground state, and PuH has a 6Π1/2 ground state at the SO-CASPT2 level. The adiabatic electron affinities (AEAs) and ionization energies (IEs) of NpH and PuH were calculated to be 0.389 and 6.156 and 0.396 and 6.296 eV, respectively, using the Feller-Peterson-Dixon approach. The AEA increases going from AcH (0.425 eV) to ThH (0.820 eV) and decreases from ThH to PuH. The IEs of Pa-Np hydrides are close to ∼6.2 eV followed by an increase of 0.14 eV to PuH (6.296 eV). The An-H bond dissociation energy (BDE) decreases from 276.4 (AcH) to 107.1 (PuH) kJ/mol; the BDE(NpH) is ∼80 kJ/mol higher than that of PuH. Natural bond orbital calculations show that the bond character for these molecules is mainly ionic, An+H-. The additional electron in NpH- and PuH- populates the 6d orbital, and NpH+ and PuH+ are formed by the removal of a 7s electron. The current work in conjunction with prior work on the AcH to UH in different charge states provides insights into how these properties change across the actinide series.

13.
Front Cell Infect Microbiol ; 13: 1113896, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36860986

RESUMO

The conventional treatment of congenital toxoplasmosis is mainly based on the combination of sulfadiazine and pyrimethamine. However, therapy with these drugs is associated with severe side effects and resistance, requiring the study of new therapeutic strategies. There are currently many studies with natural products, including Copaifera oleoresin, showing actions against some pathogens, as Trypanosoma cruzi and Leishmania. In the present study, we investigated the effects of the leaf hydroalcoholic extract and oleoresin from Copaifera multijuga against Toxoplasma gondii in human villous (BeWo) and extravillous (HTR8/SVneo) trophoblast cells, as well as in human villous explants from third-trimester pregnancy. For this purpose, both cells and villous explants were infected or not with T. gondii, treated with hydroalcoholic extract or oleoresin from C. multijuga and analyzed for toxicity, parasite proliferation, cytokine and ROS production. In parallel, both cells were infected by tachyzoites pretreated with hydroalcoholic extract or oleoresin, and adhesion, invasion and replication of the parasite were observed. Our results showed that the extract and oleoresin did not trigger toxicity in small concentrations and were able to reduce the T. gondii intracellular proliferation in cells previously infected. Also, the hydroalcoholic extract and oleoresin demonstrated an irreversible antiparasitic action in BeWo and HTR8/SVneo cells. Next, adhesion, invasion and replication of T. gondii were dampened when BeWo or HTR8/SVneo cells were infected with pretreated tachyzoites. Finally, infected and treated BeWo cells upregulated IL-6 and downmodulated IL-8, while HTR8/SVneo cells did not change significantly these cytokines when infected and treated. Finally, both the extract and oleoresin reduced the T. gondii proliferation in human explants, and no significant changes were observed in relation to cytokine production. Thus, compounds from C. multijuga presented different antiparasitic activities that were dependent on the experimental model, being the direct action on tachyzoites a common mechanism operating in both cells and villi. Considering all these parameters, the hydroalcoholic extract and oleoresin from C. multijuga can be a target for the establishment of new therapeutic strategy for congenital toxoplasmosis.


Assuntos
Fabaceae , Toxoplasmose Congênita , Gravidez , Humanos , Feminino , Trofoblastos , Placenta , Terceiro Trimestre da Gravidez , Extratos Vegetais/farmacologia , Antiparasitários , Citocinas
14.
J Phys Chem A ; 127(7): 1588-1597, 2023 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-36753327

RESUMO

The bonding and spectroscopy of the UB0/+/- and WB0/+/- molecules were examined by performing high-level electronic structure calculation on their low-lying electronic states. The calculations were performed at the SO-CASPT2 level to obtain the low-lying excited states and at the FPD level to calculate the adiabatic electronic affinities (AEA), ionization energies (IE), and bond dissociation energies (BDE). Compared to UC and UN, UB has a much denser manifold of states below 1.7 eV. The ground state of UB is predicted to be 8I5/2, and that of WB is 6Π7/2. The calculated IEs of UB and WB are 6.241 and 7.314 eV, respectively, and the corresponding AEAs are 1.160 and 1.422 eV. The BDE of UB is predicted to be 223.1 kJ/mol, which is considerably lower than those predicted for UC and UN and ∼35 kJ/mol lower than the BDE of WB. NBO calculations show that the U and B are connected by two 1-electron π bonds and one 1-electron σ bond with substantial ionic character and a bond order of 1.5. There are three unpaired electrons in the 5f on U. WB has less ionic character than UB with a doubly occupied π bond and a singly occupied σ bond for a bond order of ∼1.5. The results show that the U in UB behaves more like an actinide and the W in WB more like a transition metal.

15.
Rev. bras. entomol ; 67(2): e20230010, 2023. tab, graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1449671

RESUMO

ABSTRACT For a long time, the provenance of the specimens used by Frederick Smith to describe the species of stingless bees from Brazil remained a mystery. The recent digitalization of 19th century publications has made possible to trace the origin of the material brought to the London International Exhibition of 1862 by the Brazilian delegation. We document that the bee specimens showed at the International Exhibition, and that served as type material of the species described by Smith, were collected by Manuel Ferreira Lagos, head of the Zoology section of the Comissão Científica de Exploração, during their stay in Ceará, from 1859 to 1861. Even if late, it is important to give due credit to the Comissão Científica de Exploração, and more specifically to Lagos, for the contribution to the knowledge of the stingless bee fauna from Brazil.

16.
Rev. bras. entomol ; 67(4): e20230060, 2023. graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1521740

RESUMO

ABSTRACT The present contribution deals with the recognition of the type material of Melipona postica Latreille and the identity of the taxon it represents. The origin of the specimens studied by Illiger and Klug, and which Illiger later sent to Latreille, is traced to Francisco Agostinho Gomes, who collected the material in Salvador, Bahia, and sent them to the Count von Hoffmansegg, in Prussia. Based on material located at the Museum für Naturkunde, in Berlin, a lectotype is designated for Melipona postica Latreille. The specimen is redescribed and illustrated. The name Scaptotrigona xanthotricha Moure is placed as a synonym of S. postica.

17.
J Phys Chem A ; 126(50): 9392-9407, 2022 Dec 22.
Artigo em Inglês | MEDLINE | ID: mdl-36508745

RESUMO

A combination of high-level ab initio calculations and anion photoelectron detachment (PD) measurements is reported for the UC, UC-, and UC+ molecules. To better compare the theoretical values with the experimental photoelectron spectrum (PES), a value of 1.493 eV for the adiabatic electron affinity (AEA) of UC was calculated at the Feller-Peterson-Dixon (FPD) level. The lowest vertical detachment energy (VDE) is predicted to be 1.500 eV compared to the experimental value of 1.487 ± 0.035 eV. A shoulder to lower energy in the experimental PD spectrum with the 355 nm laser can be assigned to a combination of low-lying excited states of UC- and excited vibrational states. The VDEs calculated for the low-lying excited electronic states of UC at the SO-CASPT2 level are consistent with the observed additional electron binding energies at 1.990, 2.112, 2.316, and 3.760 eV. Potential energy curves for the Ω states and the associated spectroscopic properties are also reported. Compared to UN and UN+, the bond dissociation energy (BDE) of UC (411.3 kJ/mol) is predicted to be considerably lower. The natural bond orbitals (NBO) calculations show that the UC0/+/- molecules have a bond order of 2.5 with their ground-state configuration arising from changes in the oxidation state of the U atom in terms of the 7s orbital occupation: UC (5f27s1), UC- (5f27s2), and UC+ (5f27s0). The behavior of the UN and UC sequence of molecules and anions differs from the corresponding sequences for UO and UF.

18.
J Phys Chem A ; 126(43): 7944-7953, 2022 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-36269194

RESUMO

The results of calculations of the properties of the anion UN- including electron detachment are described, which further expand our knowledge of this diatomic molecule. High-level electronic structure calculations were conducted for the UN and UN- diatomic molecules and compared to photoelectron spectroscopy measurements. The low-lying Ω states were obtained using multireference CASPT2 including spin-orbit effects up to ∼20,000 cm-1. At the Feller-Peterson-Dixon (FPD) level, the adiabatic electron affinity (AEA) of UN is estimated to be 1.402 eV and the vertical detachment energy (VDE) is 1.423 eV. The assignment of the UN excited states shows good agreement with the experimental results with a VDE of 1.424 eV. An Ω = 4 ground state was obtained for UN- which is mainly associated with the 3H ΛS state. Thermochemical calculations estimate a bond dissociation energy (BDE) for UN- (U- + N) of 665.9 kJ/mol, ∼15% larger than that of UN and UN+. The NBO analysis reveals U-N triple bonds for the UN, UN-, and UN+ species.

19.
J Phys Chem A ; 126(36): 6171-6184, 2022 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-36053120

RESUMO

Spectroscopic and thermodynamics properties including bond dissociation energies (BDEs), adiabatic electron affinities (AEAs), and ionization energies (IEs) have been predicted for AcH and PaH using the Feller-Peterson-Dixon composite approach. Comparisons with previous studies on ThH and UH were performed to identify possible trends in the actinide series. Multireference CASPT2 calculations were used to predict the spin-orbit effects and obtain potential energy curves for the low-lying Ω states around the equilibrium distance as well as the vertical detachment energies (VDEs) from AcH- and PaH- to excited states of the neutral species. The calculated AEA for AnH (An = Ac, Th, Pa, U) showed that the AEA increases from AcH (0.425 eV) to ThH (0.820 eV) and decreases to PaH (0.781 eV) and to UH (0.457 eV), whereas the IE values are 5.887 eV (AcH), 6.181 eV (ThH), 6.204 eV (PaH), and 6.182 eV (UH). The ground state of AcH, AcH-, PaH, and PaH- are predicted to be1Σ+0,2Π3/2, 3H4, and 4I9/2, respectively. The BDEs for AcH and PaH are 276.4 and 237.2 kJ/mol, and those for AcH- and PaH- are 242.8 and 239.8 kJ/mol, respectively. The natural bond analysis shows a significant ionic character, An+H-, in the bonding of the neutral hydrides.


Assuntos
Actínio , Protoactínio , Elétrons , Modelos Moleculares , Termodinâmica
20.
Zootaxa ; 5134(1): 125-134, 2022 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-36101073

RESUMO

Scolebythidae are ectoparasitoid wasps which develop gregariously as idiobionts on wood-boring beetle larvae. Among them, the genus Clystopsenella is restricted to the Neotropical region and the eastern coast of Australia. The genus also includes a fossil species, Clystopsenella mirabilis Engel, 2015, from Miocene Dominican amber. In the present study we review the genus Clystopsenella and describe a new species from Costa Rica, Clystopsenella pacifica sp. nov. A key to the extant and extinct species is provided. The type locality of Clystopsenella longiventris Kieffer, 1911 is reinterpreted based on the original labels. The distribution of the genus is mostly confined to woodlands under tropical and subtropical climates. The biology of scolebythids is discussed based on a new host record for C. longiventris.


Assuntos
Besouros , Vespas , Âmbar , Animais , Fósseis
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