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1.
Viruses ; 15(4)2023 04 20.
Article de Anglais | MEDLINE | ID: mdl-37112998

RÉSUMÉ

Numerous studies have focused on inflammation-related markers to understand COVID-19. In this study, we performed a comparative analysis of spike (S) and nucleocapsid (N) protein-specific IgA, total IgG and IgG subclass response in COVID-19 patients and compared this to their disease outcome. We observed that the SARS-CoV-2 infection elicits a robust IgA and IgG response against the N-terminal (N1) and C-terminal (N3) region of the N protein, whereas we failed to detect IgA antibodies and observed a weak IgG response against the disordered linker region (N2) in COVID-19 patients. N and S protein-specific IgG1, IgG2 and IgG3 response was significantly elevated in hospitalized patients with severe disease compared to outpatients with non-severe disease. IgA and total IgG antibody reactivity gradually increased after the first week of symptoms. Magnitude of RBD-ACE2 blocking antibodies identified in a competitive assay and neutralizing antibodies detected by PRNT assay correlated with disease severity. Generally, the IgA and total IgG response between the discharged and deceased COVID-19 patients was similar. However, significant differences in the ratio of IgG subclass antibodies were observed between discharged and deceased patients, especially towards the disordered linker region of the N protein. Overall, SARS-CoV-2 infection is linked to an elevated blood antibody response in severe patients compared to non-severe patients. Monitoring of antigen-specific serological response could be an important tool to accompany disease progression and improve outcomes.


Sujet(s)
COVID-19 , Humains , SARS-CoV-2 , Anticorps antiviraux , Immunoglobuline G , Immunoglobuline A , Immunoglobuline M , Glycoprotéine de spicule des coronavirus
2.
Biochimie ; 208: 141-150, 2023 May.
Article de Anglais | MEDLINE | ID: mdl-36586562

RÉSUMÉ

Natural metabolites present an extraordinary chemo-diversity and have been used as the inspiration for new drugs. Considering the need for new treatments against the neglected parasitic disease leishmaniasis, three semi-synthetic derivatives of natural neolignane licarin A were prepared: O-acetyl (1a), O-allyl (1b), and 5-allyl (1c). Using an ex vivo assay, compounds 1a, 1b, and 1c showed activity against the intracellular amastigotes of Leishmania (L.) infantum, with IC50 values of 9, 13, and 10 µM, respectively. Despite no induction of hemolytic activity, only compound 1b resulted in mammalian cytotoxicity (CC50 = 64 µM). The most potent compounds (1a and 1c) resulted in selectivity indexes >18. The mechanism of action of compound 1c was evaluated by fluorescent/luminescent based techniques and MALDI-TOF/MS. After a short incubation period, increased levels of the cytosolic calcium were observed in the parasites, with alkalinization of the acidocalcisomes. Compound 1c also induced mitochondrial hyperpolarization, resulting in decreased levels of ATP without altering the reactive oxygen species (ROS). Neither plasma membrane damages nor DNA fragmentation were observed after the treatment, but a reduction in the cellular proliferation was detected. Using MALDI-TOF/MS, mass spectral alterations of promastigote proteins were observed when compared to untreated and miltefosine-treated groups. This chemically modified neolignan induced lethal alterations of the bioenergetic and protein metabolism of Leishmania. Future PKPD and animal efficacy studies are needed to optimize this promising natural-derived compound.


Sujet(s)
Antiprotozoaires , Leishmania infantum , Animaux , Souris , Antiprotozoaires/pharmacologie , Calcium/métabolisme , Leishmania infantum/métabolisme , Métabolisme énergétique , Souris de lignée BALB C , Mammifères/métabolisme
3.
Coluna/Columna ; 22(2): e273127, 2023. tab, graf, il. color
Article de Anglais | LILACS | ID: biblio-1448037

RÉSUMÉ

ABSTRACT Objective: Evaluate the influence of the most used surgical positioners for lumbar lordosis (LL) in asymptomatic individuals. Methods: Cross-sectional study based on demographic data and radiographic parameters of asymptomatic individuals. For this study, 16 volunteers, 15 males, and one female were selected, and the average age was 24.6 years. They were submitted to lateral radiographs of the lumbar spine in orthostasis in use of the following positioners: gel cushion, gel cushion with hip extension, four-point Relton-Hall and Wilson-type positioner. Results: The mean LL in the orthostatic position was 58.76º, whereas in the gel cushion positioner it was 52.51; on the gel cushion with hip extension of 58.23º, Relton-Hall/4points 37.63º and, finally, on the Wilson-type positioner of 40.87º. An average reduction of 5.42º of the LL was observed when positioning on the gel cushion in relation to the orthostasis. In the linear regression analysis, the data presented statistically significant results (p<0.05), demonstrating that the L4-S1 segment influences 60% in LL. Conclusion: The positioner with gel cushion and hip extension reproduces an LL similar to physiological values. Relton-Hall and Wilson-type positioners with hip flexion promote hypolordotic positioning compared to basal lordosis in orthostasis. Hip extension alone generated a 5.96º increase in the subject's lordosis. The L4-S1 segment has a 60% influence on the LL when the individuals are in the positioners. Level of evidence III; Controlled cross-sectional study.


RESUMO: Objetivo: Avaliar a influência dos posicionadores cirúrgicos na lordose lombar (LL) em indivíduos assintomáticos. Métodos: Estudo transversal com dados demográficos e parâmetros radiográficos de indivíduos assintomáticos. Utilizamos 16 voluntários, sendo 15 do gênero masculino e uma do gênero feminino, com idade média de 24,6 anos. Foram submetidos a realização de radiografias em perfil da coluna lombar em ortostase nos seguintes posicionadores: coxim em gel, coxim em gel com extensão do quadril, Relton-Hall em quatro pontos e posicionador tipo Wilson. Resultados: A média de LL na posição ortostática foi de 58,76º, já no posicionador coxim em gel de 52,51; no coxim em gel com extensão dos quadris de 58,23º, Relton-Hall/4pontos 37,63º e, por último, no posicionador tipo Wilson, de 40,87º. Houve redução média de 5,42º da LL ao posicionar no coxim em gel em relação a ortostase, na análise de regressão linear os dados apresentaram resultados estaticamente significativos (p<0,05), demostrando que o seguimento L4-S1 apresenta uma influência de 60% na LL. Conclusão: O posicionador coxins em gel e extensão do quadril reproduz uma LL semelhante à fisiológica. Posicionadores do tipo Relton-Hall e Wilson com flexão do quadril promovem um posicionamento hipolordótico comparada a lordose basal em ortostase. A extensão do quadril por si só foi capaz de gerar um aumento de 5,96º na lordose do indivíduo. O seguimento L4-S1 apresenta uma influência de 60% na LL quando os indivíduos estão nos posicionadores. Nível de Evidência III; Estudo Transversal Controlado.


RESUMEN: Objetivo: Evaluar la influencia de los posicionadores quirúrgicos para la lordosis lumbar (LL) en individuos asintomáticos. Métodos: Estudio transversal con datos demográficos y parámetros radiográficos de individuos asintomáticos. Utilizamos 16 voluntarios, 15 hombres y una mujer, edad media de 24,6 años. Sometidos a radiografías laterales de la columna lumbar en ortostasis en los siguientes posicionadores: almohadilla de gel, almohadilla de gel con extensión de cadera, posicionador de cuatro puntos y posicionador tipo Wilson. Resultados: El promedio de LL en posición ortostática fue de 58,76º, en el posicionador de almohadilla de gel fue de 52,51º; en almohadilla de gel con extensión de cadera de 58,23º, 4 puntos 37,63º y, por último, en posicionador tipo Wilson de 40,87º. Se observó una reducción promedio de 5,42º de LL al posicionarse sobre la almohadilla de gel en relación a ortostasis. En el análisis de regresión lineal, los datos presentaron resultados estadísticamente significativos (p<0,05), demostrando que el segmento L4-S1 tiene una influencia de 60% en LL. Conclusión: El posicionador con almohadilla de gel y con extensión de cadera reproduce una LL similar a la fisiológica. Relton-Hall y Wilson con flexión de cadera promueven el posicionamiento hipolordótico en comparación con la lordosis basal. La extensión de la cadera por sí sola fue capaz de generar un aumento de 5,96º en la lordosis. El segmento L4-S1 tiene una influencia del 60% en la LL cuando los individuos están en los posicionadores. Nivel de evidencia III; Estudio Transversal Controlado.


Sujet(s)
Humains , Adulte , Procédures orthopédiques
4.
Lancet Glob Health ; 9(11): e1508-e1516, 2021 11.
Article de Anglais | MEDLINE | ID: mdl-34678195

RÉSUMÉ

BACKGROUND: The city of Manaus, Brazil, has seen two collapses of the health system due to the COVID-19 pandemic. We report anti-SARS-CoV-2 nucleocapsid IgG antibody seroconversion rates and associated risk factors in Manaus residents before the second wave of the epidemic in Brazil. METHODS: A convenience sample of adult (aged ≥18 years) residents of Manaus was recruited through online and university website advertising into the DETECTCoV-19 study cohort. The current analysis of seroconversion included a subgroup of DETECTCoV-19 participants who had at least two serum sample collections separated by at least 4 weeks between Aug 19 and Oct 2, 2020 (visit 1), and Oct 19 and Nov 27, 2020 (visit 2). Those who reported (or had no data on) having a COVID-19 diagnosis before visit 1, and who were positive for anti-SARS-CoV-2 nucleocapsid IgG antibodies at visit 1 were excluded. Using an in-house ELISA, the reactivity index (RI; calculated as the optical density ratio of the sample to the negative control) for serum anti-SARS-CoV-2 nucleocapsid IgG antibodies was measured at both visits. We calculated the incidence of seroconversion (defined as RI values ≤1·5 at visit 1 and ≥1·5 at visit 2, and a ratio >2 between the visit 2 and visit 1 RI values) during the study period, as well as incidence rate ratios (IRRs) through cluster-corrected and adjusted Poisson regression models to analyse associations between seroconversion and variables related to sociodemographic characteristics, health access, comorbidities, COVID-19 exposure, protective behaviours, and symptoms. FINDINGS: 2496 DETECTCoV-19 cohort participants returned for a follow-up visit between Oct 19 and Nov 27, 2020, of whom 204 reported having COVID-19 before the first visit and 24 had no data regarding previous disease status. 559 participants were seropositive for anti-SARS-CoV-2 nucleocapsid IgG antibodies at baseline. Of the remaining 1709 participants who were seronegative at baseline, 71 did not meet the criteria for seroconversion and were excluded from the analyses. Among the remaining 1638 participants who were seronegative at baseline, 214 showed seroconversion at visit 2. The seroconversion incidence was 13·06% (95% CI 11·52-14·79) overall and 6·78% (5·61-8·10) for symptomatic seroconversion, over a median follow-up period of 57 days (IQR 54-61). 48·1% of seroconversion events were estimated to be asymptomatic. The sample had higher proportions of affluent and higher-educated people than those reported for the Manaus city population. In the fully adjusted and corrected model, risk factors for seroconversion before visit 2 were having a COVID-19 case in the household (IRR 1·49 [95% CI 1·21-1·83]), not wearing a mask during contact with a person with COVID-19 (1·25 [1·09-1·45]), relaxation of physical distancing (1·31 [1·05-1·64]), and having flu-like symptoms (1·79 [1·23-2·59]) or a COVID-19 diagnosis (3·57 [2·27-5·63]) between the first and second visits, whereas working remotely was associated with lower incidence (0·74 [0·56-0·97]). INTERPRETATION: An intense infection transmission period preceded the second wave of COVID-19 in Manaus. Several modifiable behaviours increased the risk of seroconversion, including non-compliance with non-pharmaceutical interventions measures such as not wearing a mask during contact, relaxation of protective measures, and non-remote working. Increased testing in high-transmission areas is needed to provide timely information about ongoing transmission and aid appropriate implementation of transmission mitigation measures. FUNDING: Ministry of Education, Brazil; Fundação de Amparo à Pesquisa do Estado do Amazonas; Pan American Health Organization (PAHO)/WHO.


Sujet(s)
COVID-19/prévention et contrôle , Épidémies , Immunoglobuline G/sang , SARS-CoV-2/immunologie , Séroconversion , Adolescent , Adulte , Sujet âgé , Anticorps antiviraux , Brésil/épidémiologie , COVID-19/épidémiologie , Femelle , Humains , Mâle , Adulte d'âge moyen , Études prospectives , Comportement social , Jeune adulte
5.
Chem Biodivers ; 18(10): e2100503, 2021 Oct.
Article de Anglais | MEDLINE | ID: mdl-34418297

RÉSUMÉ

Infections caused by parasitic worms impose a considerable worldwide health burden. One of the most impactful is schistosomiasis, a disease caused by blood-dwelling of the genus Schistosoma that affects more than 230 million people worldwide. Since praziquantel has also been extensively used to treat schistosomiasis and other parasitic flatworm infections, there is an urgent need to identify novel anthelmintic compounds, mainly from natural sources. In this study, the hexane extract from roots of Piper malacophyllum (Piperaceae) showed to be mainly composed for gibbilimbol B by HPLC/ESI-HRMS. Based on this result, this compound was isolated by chromatographic steps and its structure was confirmed by NMR. In vitro bioassays showed that gibbilimbol B was more active than praziquantel against larval stage of S. mansoni, with effective concentrations of 50 % (EC50 ) and 90 % (EC90 ) values of 2.6 and 3.4 µM, respectively. Importantly, gibbilimbol B showed no cytotoxicity to mammalian cells at a concentration 190 times greater than the antiparasitic effect, giving support for the anthelmintic potential of gibbilimbol B as lead compound for novel antischistosomal agents.


Sujet(s)
Phénols/pharmacologie , Piperaceae/composition chimique , Extraits de plantes/pharmacologie , Schistosoma mansoni/effets des médicaments et des substances chimiques , Animaux , Structure moléculaire , Phénols/composition chimique , Phénols/isolement et purification , Extraits de plantes/composition chimique , Extraits de plantes/isolement et purification , Racines de plante/composition chimique
6.
Chem Biodivers ; 18(10): e2100515, 2021 Oct.
Article de Anglais | MEDLINE | ID: mdl-34424612

RÉSUMÉ

The search for the pharmacophore of a bioactive compound, crucial for drug discovery studies, involves the adequate arrangement of different atoms in the molecule. As part of a continuous work aiming discovery of new drug candidates against the protozoan parasite Trypanosoma cruzi, the hexane extract of Hydrocotyle bonariensis was subjected to a bioactivity-guided fractionation to afford two chemically related dibenzylbutyrolactone lignans - hinokinin (1) and hibalactone (2). Compounds 1 and 2 showed activity against trypomastigote with EC50 values of 17.0 and 69.4 µM, respectively. Compound 1 was also active against the clinically relevant form of the parasite, amastigotes, displaying an EC50 value of 34.4 µM. The structure-activity relationship (SAR) indicated that the absence of the double bond at C-7 is a crucial feature for the increment of the antiparasitic activity. The lethal action of the most potent compound 1 was investigated in the trypomastigotes. The fluorescent-based assay with SYTOX Green demonstrated a significant alteration of the plasma membrane permeability of the parasite. Additionally, compound 1 demonstrated no significant hemolytic activity in mice erythrocytes at 200 µM. To search the pharmacophore, three different simplified compounds - 3,4-methylenedioxydihydrocinnamic acid (3), 3,4-methylenedioxydihydrocinnamic alcohol (4) and 3,4-methylenedioxycinnamic acid (5) - were prepared and tested against T. cruzi. These derivatives displayed EC50 values of 37.2 (3), 25.8 (4) and 73.5 (5) µM against trypomastigotes, and 41.3 (3) and 48.2 (4) µM against amastigotes, whereas compound 5 was inactive. Except for compound 2, which resulted in a CC50 value of 114.5 µM, all compounds showed no mammalian cytotoxicity at 200 µM. An in silico ADMET study was performed and predicted values demonstrated an acceptable drug-likeness profile for compounds 1-5. Despite the minor reduction in the potency, the simplified derivatives retained the antitrypanosomal activity against the intracellular amastigotes, even with 95 % reduction of their molecular weight. Additionally, in silico studies suggested them as more soluble compounds, making these simplified structures promising scaffolds for optimization studies in Chagas disease.


Sujet(s)
Apiaceae/composition chimique , Lignanes/pharmacologie , Trypanocides/pharmacologie , Trypanosoma cruzi/effets des médicaments et des substances chimiques , Lignanes/composition chimique , Lignanes/isolement et purification , Structure moléculaire , Tests de sensibilité parasitaire , Trypanocides/composition chimique , Trypanocides/isolement et purification
7.
Int J Infect Dis ; 110: 141-150, 2021 Sep.
Article de Anglais | MEDLINE | ID: mdl-34273518

RÉSUMÉ

BACKGROUND: Manaus, located in the Brazilian rainforest, has experienced two health system collapses due to the coronavirus disease 2019 (COVID-19) pandemic. However, little is known about which groups among the general population have been most affected. METHODS: A convenience sampling strategy via online advertising recruited 3046 adults between 19 August 2020 and 2 October 2020. Sociodemographic characteristics, COVID-19-related symptoms, COVID-19 testing, self-medication and prescribed medications were recorded. Serum anti-severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) nucleocapsid immunoglobulin G antibodies were measured with an enzyme-linked immunosorbent assay. Prevalence ratios (PR) were obtained using cluster-corrected and adjusted Poisson's regression models. RESULTS: A crude positivity rate among asymptomatic and symptomatic individuals was estimated at 29.10%, with maximum possible seroprevalence of 44.82% corrected by test characteristics and an antibody decay rate of 32.31%. Regression models demonstrated a strong association towards marginalized low-income and vulnerable residents with limited access to health care. The presence of a COVID-19 case [PR 1.39, 95% confidence interval (CI) 1.24-1.57] or death (PR 2.14, 95% CI 1.74-2.62) in a household greatly increased the risk of other household members acquiring infection. The seroprevalence of SARS-CoV-2 was higher among those who self-medicated to prevent infection (PR 1.36, 95% CI 1.27-1.46). CONCLUSIONS: Disproportionate socio-economic disparity was observed among the study participants. The syndemic nature of COVID-19 in the Amazon region needs differential policies and urgent solutions to control the ongoing pandemic.


Sujet(s)
COVID-19 , SARS-CoV-2 , Adulte , Anticorps antiviraux , Brésil/épidémiologie , Dépistage de la COVID-19 , Études de cohortes , Humains , Études séroépidémiologiques
8.
Phytother Res ; 35(9): 5154-5162, 2021 Sep.
Article de Anglais | MEDLINE | ID: mdl-34089558

RÉSUMÉ

Schistosomiasis is a widespread human parasitic disease currently affecting over 200 million people, particularly in poor communities. Chemotherapy for schistosomiasis relies exclusively on praziquantel (PZQ). Previous studies have shown that licarin A (LIC-A), a dihydrobenzofuran neolignan, exhibited in vitro antiparasitic activity against Schistosoma mansoni adult worms. This study aimed to investigate the potential of LIC-A, isolated as main metabolite from leaves of Nectandra oppositifolia Nees & Mart. (Lauraceae), as an antischistosomal agent orally active in schistosomiasis animal model. PZQ was used as a reference compound. As result, LIC-A showed, at a single dose of 400 mg/kg, to be able to partially cure infected mice (worm burden reductions of ~50%). Parasite eggs, that are responsible for a variety of pathologies and transmission of schistosomiasis, were also moderately inhibited by LIC-A (egg burden reductions of ~50%-60%). Furthermore, it was observed that LIC-A achieved a slight reduction of hepatomegaly and splenomegaly. Collectively, although LIC-A was partially active when administered orally, these results give support for the antiparasitic potential LIC-A as lead compound for novel antischistosomal agent.


Sujet(s)
Lauraceae , Lignanes , Schistosomiase à Schistosoma mansoni , Animaux , Lauraceae/composition chimique , Lignanes/pharmacologie , Souris , Numération des oeufs de parasites , Schistosoma mansoni , Schistosomiase à Schistosoma mansoni/traitement médicamenteux
9.
Rev Soc Bras Med Trop ; 54: e0850, 2021.
Article de Anglais | MEDLINE | ID: mdl-33886821

RÉSUMÉ

INTRODUCTION: Electron microscopy (EM) is a rapid and effective tool that can be used to create images of a whole spectrum of virus-host interactions and, as such, has long been used in the discovery and description of viral mechanisms. METHODS: Electron microscopy was used to evaluate the pulmonary pathologies of postmortem lung sections from three patients who died from infection with SARS-associated coronavirus 2 (SARS-CoV-2), a new member of the Coronaviridae family. RESULTS: Diffuse alveolar damage (DAD) was predominant in all three patients. The early exudative stage was characterized principally by edema and extravasation of red blood cells into the alveolar space with injury to the alveolar epithelial cells; this was followed by detachment, apoptosis, and necrosis of type I and II pneumocytes. The capillaries exhibited congestion, exposure of the basement membrane from denuded endothelial cells, platelet adhesion, fibrin thrombi, and rupture of the capillary walls. The proliferative stage was characterized by pronounced proliferation of type II alveolar pneumocytes and multinucleated giant cells. The cytopathic effect of SARS-CoV-2 was observed both in degenerated type II pneumocytes and freely circulating in the alveoli, with components from virions, macrophages, lymphocytes, and cellular debris. CONCLUSIONS: Viral particles consistent with the characteristics of SARS-CoV-2 were observed mainly in degenerated pneumocytes, in the endothelium, or freely circulating in the alveoli. In the final stage of illness, the alveolar spaces were replaced by fibrosis.


Sujet(s)
COVID-19 , SARS-CoV-2 , Brésil , Cellules endothéliales , Humains , Poumon , Microscopie électronique à transmission
10.
Rev. Soc. Bras. Med. Trop ; Rev. Soc. Bras. Med. Trop;54: e08502021, 2021. graf
Article de Anglais | LILACS | ID: biblio-1288094

RÉSUMÉ

Abstract INTRODUCTION: Electron microscopy (EM) is a rapid and effective tool that can be used to create images of a whole spectrum of virus-host interactions and, as such, has long been used in the discovery and description of viral mechanisms. METHODS: Electron microscopy was used to evaluate the pulmonary pathologies of postmortem lung sections from three patients who died from infection with SARS-associated coronavirus 2 (SARS-CoV-2), a new member of the Coronaviridae family. RESULTS: Diffuse alveolar damage (DAD) was predominant in all three patients. The early exudative stage was characterized principally by edema and extravasation of red blood cells into the alveolar space with injury to the alveolar epithelial cells; this was followed by detachment, apoptosis, and necrosis of type I and II pneumocytes. The capillaries exhibited congestion, exposure of the basement membrane from denuded endothelial cells, platelet adhesion, fibrin thrombi, and rupture of the capillary walls. The proliferative stage was characterized by pronounced proliferation of type II alveolar pneumocytes and multinucleated giant cells. The cytopathic effect of SARS-CoV-2 was observed both in degenerated type II pneumocytes and freely circulating in the alveoli, with components from virions, macrophages, lymphocytes, and cellular debris. CONCLUSIONS: Viral particles consistent with the characteristics of SARS-CoV-2 were observed mainly in degenerated pneumocytes, in the endothelium, or freely circulating in the alveoli. In the final stage of illness, the alveolar spaces were replaced by fibrosis.


Sujet(s)
Brésil , SARS-CoV-2 , Cellules endothéliales , Microscopie électronique à transmission , COVID-19 , Poumon
11.
Parasit Vectors ; 13(1): 278, 2020 Jun 01.
Article de Anglais | MEDLINE | ID: mdl-32487175

RÉSUMÉ

BACKGROUND: Schistosomiasis is a socioeconomically devastating parasitic infection afflicting hundreds of millions of people and animals worldwide. It is the most important helminth infection, and its treatment relies solely on the drug praziquantel. Oral H1-antihistamines are available worldwide, and these agents are among the most widely used of all medications in children and adults. Given the importance of the drug repositioning strategy, we evaluated the antischistosomal properties of the H1-antihistamine drugs commonly used in clinical practices. METHODS: Twenty-one antihistamine drugs were initially screened against adult schistosomes ex vivo. Subsequently, we investigated the anthelmintic properties of these antihistamines in a murine model of schistosomiasis for both early and chronic S. mansoni infections at oral dosages of 400 mg/kg single dose or 100 mg/kg daily for five consecutive days. We also demonstrated and described the ability of three antihistamines to induce tegumental damage in schistosomes through the use of scanning electron microscopy. RESULTS: From phenotypic screening, we found that desloratadine, rupatadine, promethazine, and cinnarizine kill adult S. mansoni in vitro at low concentrations (5-15 µM). These results were further supported by scanning electron microscopy analysis. In an animal model, rupatadine and cinnarizine revealed moderate worm burden reductions in mice harboring either early or chronic S. mansoni infection. Egg production, a key mechanism for both transmission and pathogenesis, was also markedly inhibited by rupatadine and cinnarizine, and a significant reduction in hepatomegaly and splenomegaly was recorded. Although less effective, desloratadine also revealed significant activity against the adult and juvenile parasites. CONCLUSIONS: Although the worm burden reductions achieved are all only moderate, comparatively, treatment with any of the three antihistamines is more effective in early infection than praziquantel. On the other hand, the clinical use of H1-antihistamines for the treatment of schistosomiasis is highly unlikely.


Sujet(s)
Repositionnement des médicaments , Antihistaminiques des récepteurs H1/usage thérapeutique , Schistosomiase à Schistosoma mansoni/traitement médicamenteux , Schistosomicides/usage thérapeutique , Animaux , Modèles animaux de maladie humaine , Femelle , Antihistaminiques des récepteurs H1/classification , Mâle , Souris , Charge parasitaire , Schistosoma mansoni/effets des médicaments et des substances chimiques
12.
Sci Rep ; 10(1): 5467, 2020 03 25.
Article de Anglais | MEDLINE | ID: mdl-32214193

RÉSUMÉ

Neolignan licarin A (1) was isolated from leaves of Nectandra oppositifolia (Lauraceae) and displayed activity against trypomastigote forms of the etiologic agent of American trypanosomiasis, Trypanosoma cruzi. Aiming for the establishment of SAR, five different compounds (1a - 1e) were prepared and tested against T. cruzi. The 2-allyl derivative of licarin A (1d) exhibited higher activity against trypomastigotes of T. cruzi (IC50 = 5.0 µM and SI = 9.0), while its heterocyclic derivative 1e displayed IC50 of 10.5 µM and reduced toxicity against NCTC cells (SI > 19.0). However, these compounds presented limited oral bioavailability estimation (<85%, Papp <1.0 × 10-6 cm/s) in parallel artificial membrane permeability assays (PAMPA) due to excessive lipophilicity. Based on these results, different simplified structures of licarin A were designed: vanillin (2), vanillyl alcohol (3), isoeugenol (4), and eugenol (5), as well as its corresponding methyl (a), acetyl (b), O-allyl (c), and C-allyl (d) analogues. Vanillin (2) and its acetyl derivative (2b) displayed expressive activity against intracellular amastigotes of T. cruzi with IC50 values of 5.5 and 5.6 µM, respectively, and reduced toxicity against NCTC cells (CC50 > 200 µM). In addition, these simplified analogues showed a better permeability profile (Papp > 1.0 × 10-6 cm/s) on PAMPA models, resulting in improved drug-likeness. Vanillyl alcohol acetyl derivative (3b) and isoeugenol methyl derivative (4a) displayed activity against the extracellular forms of T. cruzi (trypomastigotes) with IC50 values of 5.1 and 8.8 µM respectively. Based on these results, compounds with higher selectivity index against extracellular forms of the parasite (1d, 1e, 3d, and 4a) were selected for a mechanism of action study. After a short incubation period (1 h) all compounds increased the reactive oxygen species (ROS) levels of trypomastigotes, suggesting cellular oxidative stress. The ATP levels were increased after two hours of incubation, possibly involving a high energy expenditure of the parasite to control the homeostasis. Except for compound 4a, all compounds induced hyperpolarization of mitochondrial membrane potential, demonstrating a mitochondrial imbalance. Considering the unique mitochondria apparatus of T. cruzi and the lethal alterations induced by structurally based on licarin A, these compounds are interesting hits for future drug discovery studies in Chagas disease.


Sujet(s)
Antiparasitaires/isolement et purification , Antiparasitaires/pharmacologie , Produits biologiques/isolement et purification , Maladie de Chagas/traitement médicamenteux , Lauraceae/composition chimique , Lignanes/isolement et purification , Lignanes/pharmacologie , Feuilles de plante/composition chimique , Trypanocides/isolement et purification , Trypanocides/pharmacologie , Trypanosoma cruzi/effets des médicaments et des substances chimiques , Animaux , Antiparasitaires/synthèse chimique , Produits biologiques/synthèse chimique , Produits biologiques/pharmacologie , Découverte de médicament , Lignanes/synthèse chimique , Stress oxydatif/effets des médicaments et des substances chimiques , Phytothérapie , Espèces réactives de l'oxygène/métabolisme , Relation structure-activité , Trypanocides/synthèse chimique , Trypanosoma cruzi/métabolisme
13.
Acta Trop ; 205: 105350, 2020 May.
Article de Anglais | MEDLINE | ID: mdl-31962096

RÉSUMÉ

Schistosomiasis is one of the most important parasitic infections in terms of its negative effects on public health and economics. Since praziquantel is currently the only drug available to treat schistosomiasis, there is an urgent need to identify new anthelmintic agents. Piplartine, also known as piperlongumine, is a biologically active alkaloid/amide from peppers that can be detected in high amounts in the roots of Piper tuberculatum. Previously, it has been shown to have in vitro schistosomicidal effects. However, its anthelmintic activity in an animal host has not been reported. In the present work, in vivo antischistosomal properties of isolated piplartine were evaluated in a mouse model of schistosomiasis infected with either adult (patent infection) or juvenile (pre-patent infection) stages of Schistosoma mansoni. A single dose of piplartine (100, 200 or 400 mg/kg) or daily doses for five consecutive days (100 mg/kg/day) administered orally to mice infected with schistosomes resulted in a reduction in worm burden and egg production. Treatment with the highest piplartine dose (400 mg/kg) caused a significant reduction in a total worm burden of 60.4% (P < 0.001) in mice harbouring adult parasites. S. mansoni egg production, a process responsible for pathology in schistosomiasis, was also significantly inhibited by piplartine. Studies using scanning electron microscopy revealed substantial tegumental alterations in parasites recovered from mice. Since piplartine has well-characterized mechanisms of toxicity, is easily available, and is cost-effective, our results indicate that this bioactive molecule derived from medicinal plants could be a potential lead compound for novel antischistosomal agents.


Sujet(s)
Pipéridones/usage thérapeutique , Schistosomiase à Schistosoma mansoni/traitement médicamenteux , Schistosomicides/usage thérapeutique , Animaux , Modèles animaux de maladie humaine , Femelle , Souris , Piper/composition chimique
14.
Antimicrob Agents Chemother ; 63(12)2019 09 09.
Article de Anglais | MEDLINE | ID: mdl-31527034

RÉSUMÉ

The treatment and control of schistosomiasis, a neglected disease that affects more than 200 million people worldwide, rely on the use of a single drug, praziquantel. A vaccine has yet to be developed and since new drug design and development is a lengthy and costly process, drug repurposing is a promising strategy. In this study, the efficacy of promethazine, a first-generation antihistamine, was evaluated against Schistosoma mansoni ex vivo and in a murine model of schistosomiasis. In vitro assays demonstrated that promethazine affected parasite motility, viability, and it induced severe tegumental damage in schistosomes. The LC50 of the drug was 5.84 µM. Similar to promethazine, schistosomes incubated with atropine, a classical anticholinergic drug, displayed reduced motor activity. In an animal model, promethazine treatment was introduced at an oral dose of 100 mg/kg for five successive days at different intervals from the time of infection, for the evaluation of the stage-specific susceptibility (pre-patent and patent infections). Various parasitological criteria indicated the in vivo antischistosomal effects of promethazine: there were significant reductions in worm burden, egg production, and hepato- and splenomegaly. The highest worm burden reduction was achieved with promethazine in patent infections (> 90%). Taken together, considering the importance of the repositioning of drugs in infectious diseases, especially those related to poverty, our data revealed the possibility of promethazine repositioning as an antischistosomal agent.

15.
Bioorg Chem ; 89: 103001, 2019 08.
Article de Anglais | MEDLINE | ID: mdl-31129501

RÉSUMÉ

This work describes the isolation of six metabolites from leaves and branches of Piper cernuum (Piperaceae): (-)-cubebin (1), (-)-hinokinin (2), (-)-kusunokinin (3), trans-dehydroagarofuran (4), 11-hydroxi-4,5-secoeudesmane-4,5-dione (5), and (-)-bornyl p-coumarate (6). Antitrypanosomal activity and toxicity of purified compounds were performed in vitro against trypomastigote forms of Trypanosoma cruzi and NCTC cells, respectively. Compounds 2, 3 and 5 showed moderate activities with IC50 values of 33.1, 31.8 and 45.9 µM, respectively, while compounds 1 and 4 were inactive (IC50 > 100 µM). On the other hand, compound 6 displayed an IC50 value of 2.1 µM, a selectivity index (SI) of 18 and induced a considerable interference in the plasma membrane permeability (87%) in trypomastigotes of T. cruzi. Additionally, the lethal effect of compound 6 in T. cruzi could be associated to the plasma membrane permeability. Finally, experiments using scanning electron microscopy (SEM) confirmed the obtained results in which was possible to observe total alteration parasites topography after treatment with compound 6 in comparison to untreated parasites. These data indicated that the lethal action of compound 6 is directly related to structural disruption of the membrane.


Sujet(s)
Perméabilité des membranes cellulaires/effets des médicaments et des substances chimiques , Acides coumariques/pharmacologie , Piperaceae/composition chimique , Trypanocides/pharmacologie , Trypanosoma cruzi/effets des médicaments et des substances chimiques , Animaux , Cellules cultivées , Acides coumariques/composition chimique , Acides coumariques/isolement et purification , Relation dose-effet des médicaments , Souris , Souris de lignée BALB C , Structure moléculaire , Tests de sensibilité parasitaire , Relation structure-activité , Trypanocides/composition chimique , Trypanocides/isolement et purification
16.
Aesthetic Plast Surg ; 43(3): 866-873, 2019 06.
Article de Anglais | MEDLINE | ID: mdl-30968210

RÉSUMÉ

INTRODUCTION: In two previous studies, the quality of randomized controlled trials (RCTs) with the participation of at least one plastic surgeon was evaluated in two periods: 1966-2003 and 2004-2008. OBJECTIVE: To evaluate the evolution of the quality of RCT publications by plastic surgeons in the subsequent 5-year period, from 2009 to 2013. METHODS: RCTs published from 2009 to 2013 in English with the participation of at least one plastic surgeon were identified by electronic search and classified for concealment of allocation by two independent evaluators. The studies with adequate allocation concealment had their quality evaluated by two evaluators using the Delphi List and the Jadad Quality Scale. RESULTS: Of the 6997 identified studies, 261 were classified as to concealment of allocation. Of these, 43 (16.47%) had adequate allocation concealment. According to the evaluation in the Delphi List, there was an improvement, in relation to 1966-2003, in the items "most important characteristics of the prognosis" (p < 0.001), "use of independent evaluator" (p = 0.0029), and "measures of variability and point estimate for the primary variable" (p = 0.0057); there was no difference in relation to 2004-2008. Regarding the Jadad Quality Scale, there was an increase in scores in relation to 1966-2003 (p < 0.0004) but not in relation to the 2004-2008 period. CONCLUSION: There was no difference in the quality of publications of RCTs by plastic surgeons in the period 2009-2013 compared to the previous 5 years (2004-2008), but both periods presented higher quality than the period 1966-2003. LEVEL OF EVIDENCE III: This journal requires that authors assign a level of evidence to each article. For a full description of these evidence-based medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .


Sujet(s)
Édition , Essais contrôlés randomisés comme sujet/normes , Chirurgie plastique , Facteurs temps
17.
Rev. bras. cir. plást ; 34(1): 86-93, jan.-mar. 2019. tab
Article de Anglais, Portugais | LILACS | ID: biblio-994552

RÉSUMÉ

Introdução: Em dois estudos prévios, avaliou-se a qualidade dos ensaios clínicos aleatórios (ECAs) com a participação de pelo menos um cirurgião plástico, em dois períodos: 1966 a 2003 e 2004 a 2008. O objetivo é avaliar a evolução da qualidade das publicações de ECAs por cirurgiões plásticos no período subsequente de cinco anos, de 2009 a 2013. Métodos: ECAs publicados de 2009 a 2013, em língua inglesa, com a participação de pelo menos um cirurgião plástico, foram identificados por busca eletrônica e classificados quanto ao sigilo de alocação, por dois avaliadores independentes. Os estudos com sigilo de alocação adequado tiveram a qualidade avaliada por dois avaliadores, utilizando-se a Lista de Delphi e a Escala de Qualidade de Jadad. Resultados: Dos 6.997 estudos identificados, 261 foram classificados quanto ao sigilo de alocação. Destes, 43 (16,47%) tinham sigilo de alocação adequado. Segundo a avaliação pela Lista de Delphi, houve melhora, em relação a 1966-2003, nos itens "características mais importantes do prognóstico" (p < 0,001), "uso de avaliador independente" (p = 0,0029) e "medidas de variabilidade e estimativa de pontos para a variável primária" (p = 0,0057); não houve diferença em relação a 2004-2008. Quanto à Escala de Qualidade de Jadad, houve um aumento dos escores em relação a 1996-2003 (p < 0,0004), mas também sem diferença significante em relação ao período 2004-2008. Conclusão: Não houve diferença na qualidade das publicações de ECAs por cirurgiões plásticos no período de 2009 a 2013, em relação aos cinco anos anteriores (2004 a 2008). Entretanto, ambos os períodos apresentaram maior qualidade quando comparados ao período de 1966 a 2003.


Introduction: In two previous studies, the quality of randomized clinical trials (RCTs) with the participation of at least one plastic surgeon was assessed in two periods: from 1966 to 2003 and from 2004 to 2008. The objective is to evaluate the evolution of the quality of RCTs published by plastic surgeons in the subsequent five-year period, from 2009 to 2013. Methods: RCTs published from 2009 to 2013, in English, with the participation of at least one plastic surgeon, were identified by an electronic search and classified according to allocation concealment by two independent evaluators. The quality of the studies with adequate allocation concealment was evaluated by two evaluators using the Delphi List and the Jadad Scale. Results: Of the 6,997 identified studies, 261 were classified according to allocation concealment. Of these, 43 (16.47%) had adequate allocation concealment. According to an assessment conducted using the Delphi List, there was an improvement in the items "most important characteristics of the prognosis" (p < 0.001), "use of an independent evaluator" (p = 0.0029), and "measures of variability and estimation of points for the primary variable" (p = 0.0057) compared to the 1966-2003 assessment ; there was no difference in the assessment of the same items from 2004-2008. Regarding the Jadad Scale, there was an increase in the scores from 2009 to 2013 compared to the 1996-2003 period (p < 0.0004); however, there was no significant difference in the 2004-2008 period. Conclusion: There was no difference in the quality of the RCTs published by plastic surgeons in the 2009-2013 period compared to the previous five-year period (2004 to 2008). However, both periods indicated higher quality compared to the 1966-2003 period.


Sujet(s)
Humains , Mâle , Femelle , Adulte , Adulte d'âge moyen , Chirurgie plastique/effets indésirables , Chirurgie plastique/méthodes , Essais contrôlés randomisés comme sujet/méthodes , Essais contrôlés randomisés comme sujet/statistiques et données numériques , Essais contrôlés randomisés comme sujet/éthique , Mécanismes d'évaluation des soins de santé/statistiques et données numériques
18.
Bioorg Chem ; 84: 186-191, 2019 03.
Article de Anglais | MEDLINE | ID: mdl-30502630

RÉSUMÉ

Epi-polygodial, a drimane sesquiterpene was isolated from Drimys brasiliensis (Winteraceae). This compound demonstrated high parasite selectivity towards Trypanosoma cruzi trypomastigotes (IC50 = 5.01 µM) with a selectivity index higher than 40. These results were correlated with the effects observed when this compound was incorporated in cellular membrane models of protozoans, represented by Langmuir monolayers of dipalmitoylphosphoethanolamine (DPPE). Surface pressure-area isotherms showed that epi-polygodial expands DPPE monolayers at higher areas and condenses them at lower areas, which was attributed to the preferential interaction with the polar heads of the lipid. This mechanism of action could be corroborated with Polarization-Modulation Reflection-Absorption Spectroscopy and Brewster Angle Microscopy. These results pointed to the fact that the interaction of epi-polygodial with DPPE monolayers at the air-water interface affects the physical chemical properties of the mixed film, which may be important to comprehend the interaction of this drug with cellular membranes at the molecular level.


Sujet(s)
Membrane cellulaire/effets des médicaments et des substances chimiques , Drimys/composition chimique , Modèles biologiques , Sesquiterpènes/pharmacologie , Trypanocides/pharmacologie , Trypanosoma cruzi/effets des médicaments et des substances chimiques , Air , Relation dose-effet des médicaments , Structure moléculaire , Tests de sensibilité parasitaire , Sesquiterpènes/composition chimique , Sesquiterpènes/isolement et purification , Relation structure-activité , Trypanocides/composition chimique , Trypanocides/isolement et purification , Eau/composition chimique
19.
Rev. ABENO ; 19(3): 37-49, 2019.
Article de Portugais | BBO - Ondontologie | ID: biblio-1048031

RÉSUMÉ

Trata-se de um estudo sobre prática da educação em saúde, com ênfase no autocuidado bucal e fundamentado nas Metodologias Ativas de Ensino-Aprendizagem (MAEA). As metodologias ativas possuem, dentre suas características, o deslocamento do protagonismo do educador para o educando, incentivando a sua inserção como principal responsável pela sua aprendizagem. Objetivou interagir, debater e promover a saúde e o autocuidado, com destaque na saúde bucal, de acordo com a realidade do grupo de adolescentes no contexto do Sistema Único de Saúde. O estudo foi desenvolvido por meio de duas oficinas, totalizando a participação de 40 adolescentes, em dias distintos e sequenciados. Centrou-se na reflexão do cotidiano, nos interesses, necessidades e nos contextos social e cultural dos adolescentes, buscando estimular um processo de desconstrução/construção de conhecimentos, propiciando a busca de novos e diferentes saberes. A experiência da prática educativa relatada recebeu avaliação positiva na percepção de seus educandos, bem como facilitou o diálogo e a interação entre os mediadores e adolescentes. Verificou-se a participação intensa dos adolescentes durante as oficinas e a reflexão crítica sobre o cuidado em saúde, ligada aos problemas da vida. A prática educativa promoveu a construção de possibilidades compartilhadas ao lidar com adversidades cotidianas e conflitos familiares, pois revelouse exitosa e repleta de potencialidades crítico-reflexivas na tomada de decisão em saúde, segundo a visão dos adolescentes (AU).


This study addressed the practice of health education, with emphasis on oral self-care and based on Active Teaching-Learning Methodologies (ATLM). The active methodologies present, among their characteristics, displacement of protagonism from the educator to the student, encouraging their insertion as the main responsible for their learning. It aimed to interact, discuss and promote health and self-care, with emphasis on oral health, according to the reality of the group of adolescents within the context of the Brazilian Unified Health System. The study included two workshops, involving participation of 40 adolescents, on different and sequenced days. It focused on the reflection of daily life, interests, needs and the social and cultural contexts of adolescents, aiming to stimulate a process of deconstruction/construction of knowledge, providing the search for new and different knowledge. The reported experience of educational practice was positively evaluated in the perception of students, and facilitated the dialogue and interaction between mediators and adolescents. There was intense participation of adolescents during the workshops and critical reflection on healthcare, related to life problems. The educational practice promoted the construction of shared possibilities in dealing with daily adversities and family conflicts, as it proved to be successful and full of criticalreflexive potentialities in health decisionmaking, according to adolescents' standpoint (AU).


Sujet(s)
Humains , Mâle , Femelle , Adolescent , Politique publique , Santé buccodentaire , Éducation pour la santé , Apprentissage par problèmes/méthodes , Pratique de Santé Intégrale/méthodes , Recherche qualitative
20.
Molecules ; 19(5): 5761-76, 2014 May 05.
Article de Anglais | MEDLINE | ID: mdl-24802987

RÉSUMÉ

Leishmaniasis and Chagas are diseases caused by parasitic protozoans that affect the poorest population in the World, causing a high mortality and morbidity. As a result of highly toxic and long-term treatments, the discovery of novel, safe and more efficacious drugs is essential. In this work, the in vitro antiparasitic activity and mammalian cytotoxicity of three natural tirucallane triterpenoids, isolated from leaves of Schinus terebinthifolius (Anacardiaceae), and nine semi-synthetic derivatives were investigated against Leishmania (L.) infantum and Trypanosoma cruzi. Trypomastigotes of T. cruzi were the most susceptible parasites and seven compounds demonstrated a trypanocidal activity with IC50 values in the range between 15 and 58 µg/mL. Four compounds demonstrated selectivity towards the intracellular amastigotes of Leishmania, with IC50 values in the range between 28 and 97 µg/mL. The complete characterization of triterpenoids was afforded after thorough analysis of nuclear magnetic resonance (NMR) data as well as electrospray ionization mass spectrometry (ESI-MS). Additionally, structure-activity relationships were performed using Decision Trees.


Sujet(s)
Relation structure-activité , Triterpènes/administration et posologie , Triterpènes/synthèse chimique , Anacardiaceae/composition chimique , Anacardiaceae/effets des médicaments et des substances chimiques , Animaux , Antiparasitaires/administration et posologie , Antiprotozoaires/administration et posologie , Maladie de Chagas/traitement médicamenteux , Maladie de Chagas/génétique , Maladie de Chagas/anatomopathologie , Humains , Leishmania/effets des médicaments et des substances chimiques , Extraits de plantes/composition chimique , Feuilles de plante/composition chimique , Triterpènes/composition chimique , Trypanosoma cruzi/effets des médicaments et des substances chimiques
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