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The phytochemical investigation of the leaves and trunk bark of a specimen of Ocotea aciphylla collected in the southern portion of the Amazon forest led to the isolation of an oxabicyclo[3.2.2]nonane-type neolignan and 15 bicyclo[3.2.1]octanoid neolignans, 14 of which are unreported compounds (2-15), including one with an unusual oxidation pattern of the side chain at C-1' and two rare 7.1',8.3'-connected bicyclo[3.2.1]octanoid derivatives. Their structures and relative configurations were determined by extensive spectrometric analysis based on 1D- and 2D-NMR spectroscopy and HRESIMS data, while their absolute configurations were unambiguously assigned using electronic and vibrational circular dichroism data assisted by density functional theory calculations. Additionally, known sesquiterpenes, phenylpropanoids, and phytosterols were also isolated.
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Lignanas , Ocotea , Lignanas/química , Ocotea/química , Alcanos , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Dicroísmo CircularRESUMO
This study, performed during 2003-2005 and 2008-2009, investigated metals (Al, Fe, Ba, Zn, Mn, Cr, Cu, Ni, Cd) content in seston at Cabo Frio Bay, SE-Brazil. This study may serve as a baseline of seston metal distribution to guide biogeochemical and ecological models. The seston fractions (> 20 µm, > 64 µm, > 100 µm, and > 150 µm) were sampled in sub-surface horizontal hauls. Metals were determined by ICP-MS. The metals range: Al (62.5-56,867.6 µg g-1), Fe (23.5-25,384.0 µg g-1), Mn (2.7-336.8 µg g-1), Ba (< 0.005-356.3 µg g-1), Zn (0.5-94.2 µg g-1), Cr (0.7-35.5 µg g-1), Cu (4.3-41.7 µg g-1), Ni (< 0.005-19.1 µg g-1) and Cd (< 0.0004-2.4 µg g-1). Aluminium, Fe, Mn, Ba, and Zn showed significant differences (p < 0.05) between the seston fraction. The results obtained in this study suggest that the elements (Fe, Mn, Ba) in the seston were strongly influenced by the abiogenic source. In contrast, Zn, Cd, Cu, Cr, and Ni can be biogenic/anthropogenic sources. The significant positive linear correlation of Zn:P, Cd:P, and Cu:P can indicate an intracellular concentration higher than the external adsorption in the plankton community.
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Metais Pesados , Poluentes Químicos da Água , Baías , Brasil , Cádmio , Monitoramento Ambiental/métodos , MetaisRESUMO
BACKGROUND: Agile, accessible and cheap diagnosis of hepatitis C virus (HCV) infection is essential to achieve the elimination of this infection, worldwide, as mandated by the World Health Organzation as part of its strategy for 2030. Dried blood spots (DBS) can be an attractive alternative for sample collection among people living in remote areas and vulnerable populations due to the less invasive collection, its biosafety, and storage & transportation of samples at room temperature. DESIGN: This study aims to estimate the usefulness of dried blood spot samples for the diagnosis and the assessment of HCV infection rates in three different settings in Brazil. Cross-sectional analysis of a sample collection from different populations, aiming to assess the performance of the testing algorithms and respective procedures among different populations with diverse background infection rates. METHODS: We reported the evaluation of DBS as alternative samples for detecting anti-HCV in different groups in real life conditions: (I) Vulnerable subjects living in remote areas of Southeast, North and Northeast Brazil (n = 1464); (II) Beauticians (n = 288); (III) People who use non-injectable drugs (n = 201); (IV) patients referred to outpatient care (n = 275). RESULTS: General assay accuracy was 99%, with a weighted kappa value of 0.9, showing an excellent performance. Sensitivities ranged from 87.5% to 100.0% between groups and specificities were above 99.2%. A total of 194 individuals had HCV RNA in serum and concordance of anti-HCV detection in DBS was 98.4%. CONCLUSIONS: DBS samples could be used for anti-HCV detection in different populations recruited in real life conditions and ambulatory settings, with a high overall sensitivity and specificity.
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Hepacivirus , Hepatite C , Humanos , Hepacivirus/genética , Brasil/epidemiologia , Estudos Transversais , Estudos de Viabilidade , Populações Vulneráveis , RNA Viral , Teste em Amostras de Sangue Seco/métodos , Hepatite C/diagnóstico , Hepatite C/epidemiologia , Sensibilidade e EspecificidadeRESUMO
Recently, structural elucidation of natural products has undergone a revolution. The combined use of different modern spectroscopic methods has allowed obtaining a complete structural assignment of natural products using small amounts of sample. However, despite the extraordinary ongoing advances in spectroscopy, the mischaracterization of natural products has been and remains a recurrent problem, especially when the substance presents several stereogenic centers. The misinterpretation of nuclear magnetic resonance (NMR) data has resulted in frequent reports addressing structural reassignment. In this context, a great effort has been devoted to developing quantum chemical calculations that simulate NMR parameters accurately, allowing to achieve a more precise spectral interpretation. In this work, we employed a protocol for theoretical calculations of 1 H NMR chemical shifts and coupling constants using density functional theory (DFT), followed by the application of the DP4+ method to revisit the structure of Heliannuol L, a member of the Heliannuol class, isolated from Helianthus annuus. Our results indicate that the originally proposed structure of Heliannuol L needs a stereochemical reassignment, placing the hydroxyl bonded to C10 in the opposite side of the methyl and hydroxyl groups bonded to C7 and C8, respectively.
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Produtos Biológicos , Produtos Biológicos/química , Espectroscopia de Ressonância Magnética/métodos , Estrutura MolecularRESUMO
The combination of computational methods and experimental data from Nuclear Magnetic Resonance (NMR) is a considerably valuable tool in the elucidation of new natural product structures and, also, in the structural revision of previously reported compounds. Until recently, only classical statistical parameters were used, for example, linear correlation coefficient (R2 ), mean absolute error (MAE), or root mean square deviation (RMSD), as a way to statistically "validate" the structure pointed out by experimental NMR spectra. Regarding the resolution of the relative configuration of organic molecules, novel tools were available in the last few years to assist in the NMR elucidation process. The most relevant are DP4+, which is based on a Bayesian probability, and ANN-PRA, which is based on artificial neural networks. The combined application of these tools has become the most accurate and important alternative to solve structural and stereochemical problems in natural product chemistry. Therefore, herein, in this case study, we intended to promote these novel tools, exploring the strengths and limitations of each approach in resolving the relative configuration of the sesquiterpene alpha-bisabol. We also highlighted the advantages of the complementary use of H- and C-DP4+ to obtain optimal results in the differentiation of the stereoisomers, validating the proposal with ANN-PRA method.
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Produtos Biológicos , Teorema de Bayes , Produtos Biológicos/química , Espectroscopia de Ressonância Magnética/métodos , EstereoisomerismoRESUMO
BACKGROUND: Health and fitness apps have potential benefits to improve self-management and disease control among patients with asthma. However, inconsistent use rates have been reported across studies, regions, and health systems. A better understanding of the characteristics of users and nonusers is critical to design solutions that are effectively integrated in patients' daily lives, and to ensure that these equitably reach out to different groups of patients, thus improving rather than entrenching health inequities. OBJECTIVE: This study aimed to evaluate the use of general health and fitness apps by patients with asthma and to identify determinants of usage. METHODS: A secondary analysis of the INSPIRERS observational studies was conducted using data from face-to-face visits. Patients with a diagnosis of asthma were included between November 2017 and August 2020. Individual-level data were collected, including age, gender, marital status, educational level, health status, presence of anxiety and depression, postcode, socioeconomic level, digital literacy, use of health services, and use of health and fitness apps. Multivariate logistic regression was used to model the probability of being a health and fitness app user. Statistical analysis was performed in R. RESULTS: A total of 526 patients attended a face-to-face visit in the 49 recruiting centers and 514 had complete data. Most participants were ≤40 years old (66.4%), had at least 10 years of education (57.4%), and were in the 3 higher quintiles of the socioeconomic deprivation index (70.1%). The majority reported an overall good health status (visual analogue scale [VAS] score>70 in 93.1%) and the prevalence of anxiety and depression was 34.3% and 11.9%, respectively. The proportion of participants who reported using health and fitness mobile apps was 41.1% (n=211). Multivariate models revealed that single individuals and those with more than 10 years of education are more likely to use health and fitness mobile apps (adjusted odds ratio [aOR] 2.22, 95%CI 1.05-4.75 and aOR 1.95, 95%CI 1.12-3.45, respectively). Higher digital literacy scores were also associated with higher odds of being a user of health and fitness apps, with participants in the second, third, and fourth quartiles reporting aORs of 6.74 (95%CI 2.90-17.40), 10.30 (95%CI 4.28-27.56), and 11.52 (95%CI 4.78-30.87), respectively. Participants with depression symptoms had lower odds of using health and fitness apps (aOR 0.32, 95%CI 0.12-0.83). CONCLUSIONS: A better understanding of the barriers and enhancers of app use among patients with lower education, lower digital literacy, or depressive symptoms is key to design tailored interventions to ensure a sustained and equitable use of these technologies. Future studies should also assess users' general health-seeking behavior and their interest and concerns specifically about digital tools. These factors may impact both initial engagement and sustained use.
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Asma , Aplicativos Móveis , Adulto , Asma/epidemiologia , Asma/terapia , Exercício Físico , Comportamentos Relacionados com a Saúde , HumanosRESUMO
The purpose of this article is to report the case of a 53-year-old black man, with no previous comorbidities, who presented 48 days after a confirmed diagnosis of COVID-19, complaining of an initially insidious epigastric pain that had progressed to severe pain radiating to the interscapular vertebral region, with hyporexia and episodes of projectile vomiting, with no nausea or fever. Laboratory tests revealed no signs of acute infection or pancreatic injury. Abdominal computed tomography showed dilated, fluid-filled small bowel loops with thickened walls. After clinical treatment, the patient developed persistent abdominal pain. An exploratory laparotomy was performed, finding two sites of small bowel stenosis, with no extrinsic cause, and signs of local ischemia and considerable distension of jejunal and ileal loops. After enterectomy and side-to-side enteroanastomosis, the patient recovered satisfactorily and was discharged with a prescription for oral anticoagulants for outpatient use.
O objetivo deste artigo é relatar o caso de um homem de 53 anos de idade, negro, sem comorbidades prévias, com diagnóstico confirmado de COVID-19 há 48 dias anteriores ao início do quadro de dor epigástrica insidiosa, que evoluiu para dor de forte intensidade que irradiava para região interescapulovertebral, associada a hiporexia e episódios de vômitos em jato, sem náuseas ou febre. Os exames laboratoriais não apresentavam sinais de infecção aguda ou lesão pancreática. A tomografia computadorizada do abdome mostrou alças do intestino delgado dilatadas, cheias de líquido e com paredes espessas. Após terapia de suporte, o paciente evoluiu com dor abdominal persistente. Foi realizada laparotomia exploratória, na qual foram encontrados dois sítios de estenose no intestino delgado sem causa extrínseca, ao lado de sinais de isquemia local e distensão importante das alças jejunais e ileais. Após enterectomia e enteroanastomose primária látero-lateral, o paciente evoluiu de forma satisfatória e recebeu alta hospitalar com prescrição de anticoagulantes orais para uso ambulatorial.
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Understanding the immunological basis of resistance to gastrointestinal nematode infections in livestock is important in order to develop novel methods of parasite control such as vaccination or genetic selection for parasite resistance. The present study aimed to investigate differences in immune response between parasite resistant Santa Ines and susceptible Ile de France sheep breeds to natural Haemonchus contortus infection. Parasitological parameters, humoral immunity, local and circulating cellular immune responses were evaluated in 19 Santa Ines and 19 Ile de France lambs undergoing different anthelmintic treatments regimens: suppressive treatments (SUP) or targeted selective treatments (TST) over a 5-month grazing period. Santa Ines lambs had significantly lower Haemonchus faecal egg count and worm burden compared to Ile de France regardless of treatment regime. In addition, circulating blood eosinophils count and parasite-specific IgG levels were significantly higher and more rapidly induced in Santa Ines lambs. Abomasal immune responses were generally greater in the resistant breed, which had significantly higher levels of parasite-specific IgA in mucus, and elevated number of globule leukocytes and CD3+ T cells within the abomasal mucosal. Furthermore, numbers of POU2F3+ epithelial cells, a tuft-cell specific transcription factor, were also elevated in the Santa Ines breed, suggesting that this breed is better able to initiate T-helper type 2 immune responses within the abomasum. In conclusion, the differential immunological responses detailed here are relevant to understanding resistance to gastrointestinal nematodes in other host breeds, as well as to resistance breeding as a sustainable control approach for parasitic infections.
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Imunidade Adaptativa , Suscetibilidade a Doenças/veterinária , Gastroenteropatias/veterinária , Hemoncose/veterinária , Haemonchus/fisiologia , Imunidade Inata , Doenças dos Ovinos/imunologia , Animais , Brasil , Gastroenteropatias/imunologia , Gastroenteropatias/parasitologia , Hemoncose/imunologia , Hemoncose/parasitologia , Imunidade Celular , Imunidade Humoral , Ovinos , Doenças dos Ovinos/parasitologia , Carneiro DomésticoRESUMO
BACKGROUND: Patients treated for invasive aspergillosis may relapse during subsequent periods of immunosuppression and should receive secondary prophylaxis. Little is known about the frequency of relapse and practices of secondary prophylaxis for invasive fusariosis (IF). OBJECTIVES: Evaluate practices of secondary prophylaxis and the frequency of relapse in patients who survived IF and were exposed to subsequent periods of immunosuppression. METHODS: Multicentre retrospective study of patients with haematological malignancies who developed IF, survived the initial fungal disease period, and were exposed to subsequent periods of immunosuppression. RESULTS: Among 40 patients, 35 received additional chemotherapy and developed neutropenia (median, 24 days; range, 4-104), and five received glucocorticoids for the treatment of graft-vs-host disease. Overall, 32 patients received secondary prophylaxis (voriconazole in 24) for a median of 112 days (range, 12-468). IF relapsed in five patients (12.5%): 2/8 (25%) not on prophylaxis and 3/32 (9.4%) receiving prophylaxis. Among 28 patients with disseminated IF, relapse occurred in 2/2 (100%) not on prophylaxis and in 3/26 (11.5%) on prophylaxis (P = 0.03). All patients who relapsed IF died. CONCLUSIONS: Patients with IF who survive the initial disease may relapse if exposed to subsequent episodes of immunosuppressive therapies. Secondary prophylaxis should be considered, especially if IF was disseminated.
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Quimioprevenção/métodos , Fusariose/tratamento farmacológico , Fusariose/prevenção & controle , Hospedeiro Imunocomprometido , Imunossupressores/efeitos adversos , Imunossupressores/uso terapêutico , Prevenção Secundária/métodos , Adolescente , Adulto , Idoso , Criança , Pré-Escolar , Feminino , Fusariose/epidemiologia , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Recidiva , Estudos Retrospectivos , Adulto JovemRESUMO
Stable isotopes have been widely used in the literature both to discuss current ocean circulation processes, as well as to reconstitute paleoceanographic parameters. The distribution of oxygen and deuterium stable isotopes in seawater (δ18Osw and δDsw) at the Western Tropical South Atlantic border was investigated to better understand the main fractionation processes of these isotopes and establish a regional salinity and δ18Osw relation to improve the paleoceanographic knowledge in the region. This study was conducted during a quasi-synoptic oceanographic cruise in which 98 discrete seawater samples were collected in the core of the main water masses for stable isotope analysis. A strong correlation between δ18Osw and δD was found, which made it possible to extrapolate the results for δ18Osw to δD. Although it was not possible to distinguish the water masses based only on their isotopic signatures, the water masses had a strong salinity and δ18Osw relation, and compared with previous studies, a seasonal pattern was observed. Paleosalinity differences of up to 0.2 psu between Summer and Winter are reported. Considering the limitations of the current techniques to seasonally separate the samples for the paleoceanographic studies, an intermediate Mixing Line for the Tropical South Atlantic (SSS = 1.942* δ18Osw + 34.56) was proposed to reduce the estimated errors associated with these seasonal variations.
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Isótopos de Oxigênio/química , Salinidade , Água do Mar/química , Clima Tropical , Oceano Atlântico , Brasil , Oceanografia , Estações do Ano , TemperaturaRESUMO
BACKGROUND: Negative symptoms are a core feature of schizophrenia. The Brief Negative Symptom Scale (BNSS) is a scale developed to measure negative symptoms in schizophrenia. METHODS: The present study aimed to examine the construct validity of BNSS, by using convergent and divergent validities as well as factor analysis, in a Brazilian sample of 111 outpatients diagnosed with schizophrenia by DSM-5. Patients were evaluated by the Brazilian version of the BNSS and positive and negative subscales of the Positive and Negative Syndrome Scale (PANSS). RESULTS: Assessment of patients by both instruments revealed an excellent internal consistency (Cronbach's alphaâ¯=â¯0.938) or inter-rater reliability (ICCâ¯=â¯0.92), as well as a strong correlation between BNSS and Marder negative PANSS (râ¯=â¯0.866) and a weak correlation of the instrument with the positive PANSS (râ¯=â¯0.292), thus characterizing convergent and discriminant validities, respectively. The exploratory factor analysis identified two distinct factors, namely, motivation/pleasure and emotional expressivity, accounting for 68.63% of the total variance. CONCLUSION: The study shows that the Brazilian version of the BNSS has adequate psychometric properties and is a reliable instrument for the assessment of negative symptoms in schizophrenia, either for clinical practice or research.
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Escalas de Graduação Psiquiátrica/normas , Psicometria/normas , Esquizofrenia/diagnóstico , Esquizofrenia/fisiopatologia , Adulto , Brasil , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos TestesRESUMO
Four species of Mammomonogamus are known from large African herbivores. A recent study demonstrated that a single Mammomonogamus species was shared by both western lowland gorillas (Gorilla gorilla gorilla) and African forest elephants (Loxodonta cyclotis) in Central African Republic, suggesting lower species diversity than previously described in literature. We examined more than 500 fecal samples collected from sympatric African forest elephants, western lowland gorillas, and African forest buffaloes (Syncerus caffer nanus) at four study sites across Central Africa and examined them by coproscopic methods to detect Mammomonogamus eggs, which were found at three of the study sites. Subsequently, sequences of 18S rDNA, 28S rDNA, and cox1 amplified from individual eggs were analyzed. Phylogenetic analyses of both nuclear and mitochondrial DNA revealed two clades: one formed by sequences originating from Gabonese buffaloes and the other comprising gorillas and elephants. The gorilla-elephant clade was further differentiated depending on the locality. We show the existence of at least two distinct species of Mammomonogamus, M. loxodontis in elephants and gorillas and M. nasicola in buffaloes. The available information on Mammomonogamus in African herbivores is reviewed.
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Entamoeba/genética , Entamoeba/isolamento & purificação , Helmintíase Animal/parasitologia , Strongyloidea , Animais , Búfalos/parasitologia , Carboxipeptidases/genética , República Centro-Africana , DNA Mitocondrial/genética , DNA Ribossômico/genética , Elefantes/parasitologia , Fezes/parasitologia , Feminino , Gorilla gorilla/parasitologia , Herbivoria , Interações Hospedeiro-Parasita , Humanos , Masculino , Filogenia , RNA Ribossômico 18S/genética , RNA Ribossômico 28S/genética , Strongyloidea/classificação , Strongyloidea/genética , Strongyloidea/isolamento & purificaçãoRESUMO
Chronic kidney disease is associated with a high prevalence of depression, which increases inversely with the glomerular filtration rate. This paper aims to evaluate the factors associated with a low quality of life and depression in patients on haemodialysis. Two hundred patients undergoing haemodialysis answered the Medical Outcomes Study 36 - Item Short - Form Health Survey (SF-36) and Beck Depression Inventory (BDI). Clinical and laboratory variables were analysed and correlated with these two tools. The prevalence of depression was 29%. Anaemia and hypoalbuminemia were independent risk factors for depression. All SF-36 domains showed worse results in patients with depression, and the pain domain presented the highest correlation. Our findings provide evidence that patients on haemodialysis have a low quality of life and a high prevalence of depression. A greater number of comorbidities, an excessive number of medications, diabetes mellitus, anaemia and hypoalbuminemia were associated with a reduced quality of life.
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Depressão/epidemiologia , Transtorno Depressivo/epidemiologia , Falência Renal Crônica/terapia , Qualidade de Vida , Adulto , Anemia/epidemiologia , Anemia/psicologia , Antidepressivos/uso terapêutico , Brasil/epidemiologia , Comorbidade , Estudos Transversais , Depressão/psicologia , Transtorno Depressivo/tratamento farmacológico , Transtorno Depressivo/psicologia , Diabetes Mellitus/epidemiologia , Diabetes Mellitus/psicologia , Feminino , Humanos , Hipoalbuminemia/epidemiologia , Hipoalbuminemia/psicologia , Falência Renal Crônica/psicologia , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Dor , Polimedicação , Prevalência , Escalas de Graduação Psiquiátrica , Diálise Renal/psicologia , Fatores de RiscoRESUMO
Parabens are the most widely used preservative and are considered to be relatively safe compounds. However, studies have demonstrated that they may have estrogenic activity, and there is ongoing debate regarding the safety and potential cancer risk of using products containing these compounds. In the present work, liquid chromatography-tandem mass spectrometry was applied to determine methylparaben and propylparaben concentrations in serum, and the results were correlated with lipstick application. Samples were analyzed using liquid-liquid extraction, followed by liquid chromatography-tandem mass spectrometry. The validation results demonstrated the linearity of the method over a range of 1-20 ng/mL, in addition to the method's precision and accuracy. A statistically significant difference was demonstrated between serum parabens in women who used lipstick containing these substances compared with those not using this cosmetic (p = 0.0005 and 0.0016, respectively), and a strong association was observed between serum parabens and lipstick use (Spearman correlation = 0.7202).
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Cromatografia Líquida , Cosméticos/análise , Parabenos/análise , Espectrometria de Massas por Ionização por Electrospray , Espectrometria de Massas em Tandem , Adulto , Biomarcadores/sangue , Calibragem , Cromatografia Líquida/normas , Cosméticos/efeitos adversos , Feminino , Humanos , Modelos Lineares , Parabenos/efeitos adversos , Padrões de Referência , Reprodutibilidade dos Testes , Medição de Risco , Espectrometria de Massas por Ionização por Electrospray/normas , Espectrometria de Massas em Tandem/normas , Adulto JovemRESUMO
Amazonia, the largest Brazilian biome, is one of the most diverse biomes around the world. Considering the Brazilian chiropteran species, 120 out of known 167 species are registered in Pará state, with 10 endemic species. Despite the high diversity of bats in Amazonia, studies on their parasites, especially on helminths, are scarce. Therefore, the present study aims to study the helminth fauna of different bats from the Pará state, Amazon biome, determine the descriptors of infection, and evaluate the host-parasite interactions, as well as evaluate differences in ecological indexes in accordance with the feeding guilds. The study was developed on 67 bats of 21 species captured in several areas of the Pará state. The animals were identified, divided into feeding guilds, and necropsied. The parasites obtained were identified and quantified. A total of 182 parasites were found in 20.89 % of the studied bats, representing nine species, as follows: Anenterotrema eduardocaballeroi, Anenterotrema liliputianum, Ochoterenatrema caballeroi, Tricholeiperia sp., Parahistiostrongylus octacanthus, Litomosoides guiterasi, Litomosoides brasiliensis, Capillariinae gen. sp., and Hymenolepididae gen. sp. Also, the results indicated that there was no impact of parasitism on host body condition and no relationship between sex and parasite intensity. In relation to the feeding guilds, the omnivores showed higher prevalence and mean intensity. Animals from regions closer to the equator tend to have greater richness in parasite species, but the present study revealed low diversity and richness in species. In conclusion, the ecological pattern observed for other animal groups, in which higher parasitic diversity are registered in lower latitudes, is not applicable to chiropterans from the study area.
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Quirópteros/parasitologia , Helmintos/isolamento & purificação , Helmintos/fisiologia , Interações Hospedeiro-Parasita , Animais , Brasil , Quirópteros/classificação , Quirópteros/fisiologia , Ecologia , Feminino , Helmintos/classificação , Helmintos/genética , Masculino , PrevalênciaRESUMO
(-)-Centratherin is a bioactive sesquiterpenoid lactone, whose absolute configuration (AC) was not established, but has been proposed based on those of germacrane precursors. To verify this proposal, the experimental electronic circular dichroism (ECD), electronic dissymmetry factor (EDF), optical rotatory dispersion (ORD), vibrational circular dichroism (VCD), and vibrational dissymmetry factor (VDF) spectra of (-)-centratherin have been analyzed with the corresponding density functional theoretical predictions. These analyses suggest the AC of naturally occurring (-)-centratherin to be (6R,7R,8S,10R,2'Z).
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Lactonas/química , Sesquiterpenos/química , Dicroísmo Circular , Lactonas/farmacologia , Modelos Químicos , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular , Dispersão Óptica Rotatória , Sesquiterpenos/farmacologia , EstereoisomerismoRESUMO
This work addresses the design and configuration of a Eulerian sediment trap mooring array, which was deployed at the shelf edge (zm ≈ 140 m) 80 km off Cabo Frio, SE- Brazil (23° S). The site was subject to interplay between the Tropical Waters (TW) of the Brazil Current (BC), intrusions from the South Atlantic Central Waters (SACW), which are the source of upwelling in the region, and other oceanographic processes. Detailed computations were used to optimize the total weight, buoyancy balance, and maximum acceptable tilt to avoid hydrodynamic bias in the trapping efficiency and array adaptation to the local oceanographic conditions with the assistance of Matlab and Muringa programs and Modular Ocean Model 4.0 (MOM; i.e., to assert the vertical distribution of the meridional current component). The velocity range of the current component was determined by short term measurements to be between 0.1 and 0.5 m/s. Projections led to a resulting minimum anchor weight of 456 kg. The necessary line tension was ascertained by using the appropriate distribution of a series of buoys along the array, which finally attained a high vertical load of 350 kg because of the attached oceanographic equipment. Additional flotation devices resulted in a stable mooring array as reflected by their low calculated tilt (2.6° ± 0.6°). A low drag of 16 N was computed for the maximum surface current velocity of 0.5 m/s. The Reynolds number values ranged from 4 × 104 to 2 × 105 and a cone-trap aspect ratio of 1.75 was used to assess the trap sampling efficiency upon exposure to different current velocities.
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Physical and biogeochemical processes in continental shelves act synergistically in both transporting and transforming suspended material, and ocean dynamics control the dispersion of particles by the coastal zone and their subsequent mixing and dilution within the shelf area constrained by oceanic boundary currents, followed by their gradual settling in a complex sedimentary scenario. One of these regions is the Cabo Frio Upwelling System located in a significantly productive area of Southeastern Brazil, under the control of the nutrient-poor western boundary Brazil Current but also with a wind-driven coastal upwelling zone, inducing cold-water intrusions of South Atlantic Central Water on the shelf. To understand these synergic interactions among physical and biogeochemical processes in the Cabo Frio shelf, a series of four experiments with a total of 98 discrete samples using sediment traps was performed from November 2010 to March 2012, located on the 145 m isobath on the edge of the continental shelf. The results showed that lateral transport might be relevant in some cases, especially in deep layers, although no clear seasonal cycle was detected. Two main physical-geochemical coupling scenarios were identified: singular downwelling events that can enhance particles fluxes and are potentially related to the Brazil Current oscillations; and events of significant fluxes related to the intrusion of the 18°C isotherm in the euphotic zone. The particulate matter settling in the Cabo Frio shelf area seems to belong to multiple marine and terrestrial sources, in which both Paraiba do Sul River and Guanabara Bay could be potential land-sources, although the particulate material might subject intense transformation (diagenesis) during its trajectory to the shelf edge.
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This long-term study, performed during the years 2003-2005 and 2008-2009, investigated the carbon (C), nitrogen (N), and phosphorus (P) contents of the phyto- and zooplankton communities and the nutrient regime of Cabo Frio Bay, SE Brazil. The information intends to serve as baseline of the plankton C, N, and P stoichiometry for the calibration of biogeochemical and ecological models in support to future findings related to the local and regional phenomena of climatic change. Cabo Frio Bay is a small semienclosed system set adjacent to a region subject to sporadic coastal upwelling. Zooplankton exhibited average annual C, N, and P contents of 11.6 ± 6.9 %, 2.8 ± 1.8 %, and 0.18 ± 0.08 %, and phytoplankton (>20 µm) 6.8 ± 6.0 %, 1.6 ± 1.5 %, and 0.09 ± 0.08 %, respectively. The C/N/P ratios correspond to the lowest already found to date for a marine environment. The low C contents must have been brought about by a predominance of gelatinous zooplankton, like Doliolids/ Salps and also Pteropods. Average annual nutrient concentrations in the water were 0.21 ± 0.1 µM for phosphate, 0.08 ± 0.1 µM for nitrite, 0.74 ± 1.6 µM for nitrate, and 1.27 ± 1.1 µM for ammonium. N/P ratios were around 8:1 during the first study period and 12:1 during the second. The plankton C/N/P and N/P nutrient ratios and elemental concentrations suggest that the system was oligotrophic and nitrogen limited. The sporadic intrusions of upwelling waters during the first study period had no marked effect upon the systems metabolism, likely due to dilution effects and the short residence times of water of the bay.
Assuntos
Carbono/análise , Monitoramento Ambiental , Nitrogênio/análise , Fósforo/análise , Plâncton/fisiologia , Poluentes Químicos da Água/análise , Baías , Brasil , Carbono/metabolismo , Ecossistema , Nitrogênio/metabolismo , Fósforo/metabolismo , Poluentes Químicos da Água/metabolismoRESUMO
Loss of kidney function causes oral manifestations and multiple complications that have implications for dental treatment and patients' systemic conditions. We aimed to determine the clinical condition, epidemiological profile, and incidence of dental caries in patients with chronic kidney disease (CKD). This was an observational, cross-sectional, field study using a quantitative and epidemiological approach. The sample consisted of 45 randomly selected patients with CKD from a total of 114 patients. Data were collected through oral clinical examination, anamnesis, and medical records compiled in a clinical file specially developed for this research. Clinical evaluation was performed, including a Decayed, Missing, and Filled Teeth (DMFT) index examination. Data were analyzed using the Shapiro-Wilk test, Mann-Whitney test, and Spearman's rho coefficient. All analyses were performed using IBM SPSS Statistics software version 20.0, with a confidence interval of 95 % and significance level of 5 % (p < 0.05). The results indicated that CKD is more prevalent in the 5th decade of life, with a slight predilection for men. Oral cavity alterations were observed in 77.8 % of patients. The study population had a very high DMFT index, with a high number of missing teeth and a low number of decayed and filled teeth. Poor oral health in patients with CKD indicates a lack of care that supports the necessity of installing a preventive and therapeutic oral program and a regular follow-up aimed at this group of patients.