Evaluation of Antiplasmodial activity of extracts and constituents from Ampelozizyphus amazonicus

PMID: 26664012 WOS: 000362879000003BACKGROUND: Ampelozizyphus amazonicus Ducke, a plant that is widely used by the population of the Amazonian region to prevent and treat malaria, was investigated in this work, which describes, for the first time, the antiplasmodial activity of its extracts and associates this activity with its isolated constituents. METHODS: Different extracts with solvents of increasing polarity (hexane, chloroform, ethanol, and water) were obtained of the root bark. This procedure resulted in extracts that were characterized for their constituents. The cytotoxicity and activity of the extracts against Plasmodium berghei (schizontocidal activity, liver stage) and Plasmodium falciparum (3D7 and Dd2 strains, erythrocyte stage) were assessed in vitro. RESULTS: Of the four extracts assayed against P. berghei, the chloroform extract showed the greatest activity, with an inhibitory concentration 50% (IC50) value of 30.1 µg/mL, followed by the aqueous extract (IC50 = 39.9 µg/mL). The chloroform extract exhibited the highest antiplasmodial activity in the erythrocyte stage of P. falciparum, with an IC50 value lower than 15 µg/mL. Fractionation of this more active extract led to the isolation and elucidation of pentacyclic triterpenes, lupeol, betulin and betulinic acid, which showed antiplasmodial activities with IC50 values ranging from 5.6 to 80.30 µM. The most active of these, betulinic acid, was further quantified in the extracts by high-performance liquid chromatography-photodiode array detector analyzes. The higher amount was found in the chloroform extract, which was the most active one against P. falciparum. CONCLUSION: The results obtained in this work may partly explain the popular intake of A. amazonicusas an antimalarial remedy in the Amazon region.publishersversionpublishe

Prevalence of antibodies and risk factors associated with infection by Toxoplasma gondii in free range chickens of rural area of Santa Maria, Rio Grande do Sul, Brazil

Toxoplasma gondii is an apicomplex protozoan that infects warm-blooded animals and can be considered a major parasite capable of infecting humans. Domestic chickens can be easily infected by protozoa, since they can ingest oocysts found in the soil and are considered good indicators of environmental contamination by T. gondii. The aim of this study was to determine the presence of anti-T. gondii antibodies in free range chickens and to evaluate the risks factors associated with the protozoan in rural area of Santa Maria, RS, Brazil. From March 2013 to February 2014, 597 blood samples from domestic chickens were collected from 74 farms, from nine layers representing each district in the rural area. To evaluate the risk factors, in these farms an epidemiological questionnaire was applied to the residents. Serum samples were tested by indirect immunofluorescence and 49.2% (294/597) were positive for anti-T. gondii antibodies, with titres varying from 16 to 4096. Of the 74 analyzed farms, 63 (85.1%) reported that cats had access to food deposits, with a significant association when positive chickens were present (p = 0.04) and the OR of 4.07. The variable "slaughter of animals" (poultry and cattle) in 51 (68.9%) of the farms was reported the slaughter of cattle and birds in the farm, with significant p value (p = 0.05). Most farms 59 (79.7%) reported the presence of domestic cats, which could be associated with the high seroprevalence found in chickens and the rate of environmental contamination. The high prevalence of antibodies found in this study, in addition to the high frequency of farms with positive cases, suggests a great environmental contamination in the studied districts, thus being a potential risk to human and animal health.Toxoplasma gondii é um protozoário apicomplexa que infecta animais de sangue quente, podendo ser considerado um dos principais parasitas capazes de infectar os seres humanos. Galinhas domésticas podem ser facilmente infectadas por protozoários, uma vez que estas podem ingerir oocistos encontrados no solo, sendo consideradas boas indicadoras de contaminação ambiental por T. gondii. O objetivo deste estudo foi determinar a presença de anticorpos anti-T. gondii em galinhas domésticas criadas extensivamente e avaliar os fatores de risco associados ao protozoário, na zona rural de Santa Maria, RS, Brasil. No período de março de 2013 a fevereiro 2014 foram coletadas 597 amostras de sangue de galinhas domésticas em 74 propriedades, oriundas de nove estratos que representam cada distrito da zona rural. Para avaliar os fatores de risco, nessas propriedades foi aplicado um questionário epidemiológico aos moradores. As amostras de soro foram testadas por imunofluorescência indireta, e 49,2% (294/597) foram positivas para anticorpos anti-T. gondii, com títulos variando de 16 a 4096. Das 74 propriedades analisadas, em 63 (85,1%) houve relatos que os gatos têm acesso ao deposito de alimentos, com associação significativa quando associado à presença de galinhas positivas (p=0,04) e o OR de 4,07. A variável “abate de animais” (aves e bovinos), em 51 (68,9%) das propriedades foi relatado o abate de bovinos e aves na propriedade, com valor de p significativo (p=0,05). A maioria das propriedades 59 (79,7%) foi relatada a presença de gatos domésticos, o que poderia estar associada com a alta soroprevalência encontrada em galinhas e a taxa de contaminação ambiental. A elevada prevalência de anticorpos encontrada neste estudo, além da alta frequência de propriedades com casos positivos, sugere uma grande contaminação ambiental nos distritos pesquisados, sendo assim um risco potencial para a saúde humana e animal.Facultad de Ciencias Veterinaria

Prevalence of antibodies and risk factors associated with infection by Toxoplasma gondii in free range chickens of rural area of Santa Maria, Rio Grande do Sul, Brazil

Toxoplasma gondii is an apicomplex protozoan that infects warm-blooded animals and can be considered a major parasite capable of infecting humans. Domestic chickens can be easily infected by protozoa, since they can ingest oocysts found in the soil and are considered good indicators of environmental contamination by T. gondii. The aim of this study was to determine the presence of anti-T. gondii antibodies in free range chickens and to evaluate the risks factors associated with the protozoan in rural area of Santa Maria, RS, Brazil. From March 2013 to February 2014, 597 blood samples from domestic chickens were collected from 74 farms, from nine layers representing each district in the rural area. To evaluate the risk factors, in these farms an epidemiological questionnaire was applied to the residents. Serum samples were tested by indirect immunofluorescence and 49.2% (294/597) were positive for anti-T. gondii antibodies, with titres varying from 16 to 4096. Of the 74 analyzed farms, 63 (85.1%) reported that cats had access to food deposits, with a significant association when positive chickens were present (p = 0.04) and the OR of 4.07. The variable "slaughter of animals" (poultry and cattle) in 51 (68.9%) of the farms was reported the slaughter of cattle and birds in the farm, with significant p value (p = 0.05). Most farms 59 (79.7%) reported the presence of domestic cats, which could be associated with the high seroprevalence found in chickens and the rate of environmental contamination. The high prevalence of antibodies found in this study, in addition to the high frequency of farms with positive cases, suggests a great environmental contamination in the studied districts, thus being a potential risk to human and animal health.Toxoplasma gondii é um protozoário apicomplexa que infecta animais de sangue quente, podendo ser considerado um dos principais parasitas capazes de infectar os seres humanos. Galinhas domésticas podem ser facilmente infectadas por protozoários, uma vez que estas podem ingerir oocistos encontrados no solo, sendo consideradas boas indicadoras de contaminação ambiental por T. gondii. O objetivo deste estudo foi determinar a presença de anticorpos anti-T. gondii em galinhas domésticas criadas extensivamente e avaliar os fatores de risco associados ao protozoário, na zona rural de Santa Maria, RS, Brasil. No período de março de 2013 a fevereiro 2014 foram coletadas 597 amostras de sangue de galinhas domésticas em 74 propriedades, oriundas de nove estratos que representam cada distrito da zona rural. Para avaliar os fatores de risco, nessas propriedades foi aplicado um questionário epidemiológico aos moradores. As amostras de soro foram testadas por imunofluorescência indireta, e 49,2% (294/597) foram positivas para anticorpos anti-T. gondii, com títulos variando de 16 a 4096. Das 74 propriedades analisadas, em 63 (85,1%) houve relatos que os gatos têm acesso ao deposito de alimentos, com associação significativa quando associado à presença de galinhas positivas (p=0,04) e o OR de 4,07. A variável “abate de animais” (aves e bovinos), em 51 (68,9%) das propriedades foi relatado o abate de bovinos e aves na propriedade, com valor de p significativo (p=0,05). A maioria das propriedades 59 (79,7%) foi relatada a presença de gatos domésticos, o que poderia estar associada com a alta soroprevalência encontrada em galinhas e a taxa de contaminação ambiental. A elevada prevalência de anticorpos encontrada neste estudo, além da alta frequência de propriedades com casos positivos, sugere uma grande contaminação ambiental nos distritos pesquisados, sendo assim um risco potencial para a saúde humana e animal.Facultad de Ciencias Veterinaria

Protein O-Fucosyltransferase 2 Is Not Essential for Plasmodium berghei Development

Thrombospondin type I repeat (TSR) domains are commonly O-fucosylated by protein O-fucosyltransferase 2 (PoFUT2), and this modification is required for optimal folding and secretion of TSR-containing proteins. The human malaria parasite Plasmodium falciparum expresses proteins containing TSR domains, such as the thrombospondin-related anonymous protein (TRAP) and circumsporozoite surface protein (CSP), which are O-fucosylated. TRAP and CSP are present on the surface of sporozoites and play essential roles in mosquito and human host invasion processes during the transmission stages. Here, we have generated PoFUT2 null-mutant P. falciparum and Plasmodium berghei (rodent) malaria parasites and, by phenotyping them throughout their complete life cycle, we show that PoFUT2 disruption does not affect the growth through the mosquito stages for both species. However, contrary to what has been described previously by others, P. berghei PoFUT2 null mutant sporozoites showed no deleterious motility phenotypes and successfully established blood stage infection in mice. This unexpected result indicates that the importance of O-fucosylation of TSR domains may differ between human and RODENT malaria parasites; complicating our understanding of glycosylation modifications in malaria biology

Deciphering the contribution of biofilm to the pathogenesis of peritoneal dialysis infections: characterization and microbial behaviour on dialysis fluids

Infections are major complications in peritoneal dialysis (PD) with a multifactorial etiology that comprises patient, microbial and dialytic factors. This study aimed at investigating the contribution of microbial biofilms on PD catheters to recalcitrant infections and their interplay with PD related-factors. A prospective observational study was performed on 47 patients attending Centro Hospitalar of Porto and Vila Nova de Gaia/Espinho to whom the catheter was removed due to infectious (n = 16) and non-infectious causes (n = 31). Microbial density on the catheter was assessed by culture methods and the isolated microorganisms identified by matrix-assisted laser desorption/ionization time-of-flight intact cell mass spectrometry. The effect of conventional and three biocompatible PD solutions on 16 Coagulase Negative Staphylococci (CNS) and 10 Pseudomonas aeruginosa strains planktonic growth and biofilm formation was evaluated. Cultures were positive in 87.5% of the catheters removed due infectious and 90.3% removed due to non-infectious causes. However, microbial yields were higher on the cuffs of catheters removed due to infection vs. non-infection. Staphylococci (CNS and Staphylococcus aureus) and P. aeruginosa were the predominant species: 32% and 20% in the infection and 43.3% and 22.7% in the non-infection group, respectively. In general, PD solutions had a detrimental effect on planktonic CNS and P. aeruginosa strains growth. All strains formed biofilms in the presence of PD solutions. The solutions had a more detrimental effect on P. aeruginosa than CNS strains. No major differences were observed between conventional and biocompatible solutions, although in icodextrin solution biofilm biomass was lower than in bicarbonate/lactate solution. Overall, we show that microbial biofilm is universal in PD catheters with the subclinical menace of Staphylococci and P. aeruginosa. Cuffs colonization may significantly contribute to infection. PD solutions differentially impact microbial species. This knowledge is important for the development of infection diagnosis, treatment and preventive strategies.This work received support from a Sociedade Portuguesa de Nefrologia (http://www.spnefro.pt) research grant to AR and a Fundação para a Ciência e Tecnologia (http://www.fct.pt) post doc grant (SFRH/BPD/73663/2010) to MM. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript

A framework for remission in SLE: consensus findings from a large international task force on definitions of remission in SLE (DORIS)

Objectives Treat-to-target recommendations have identified 'remission' as a target in systemic lupus erythematosus (SLE), but recognise that there is no universally accepted definition for this. Therefore, we initiated a process to achieve consensus on potential definitions for remission in SLE. Methods An international task force of 60 specialists and patient representatives participated in preparatory exercises, a face-to-face meeting and follow-up electronic voting. The level for agreement was set at 90%. Results The task force agreed on eight key statements regarding remission in SLE and three principles to guide the further development of remission definitions: 1. Definitions of remission will be worded as follows: remission in SLE is a durable state characterised by . (reference to symptoms, signs, routine labs). 2. For defining remission, a validated index must be used, for example, clinical systemic lupus erythematosus disease activity index (SLEDAI)=0, British Isles lupus assessment group (BILAG) 2004 D/E only, clinical European consensus lupus outcome measure (ECLAM)=0; with routine laboratory assessments included, and supplemented with physician's global assessment. 3. Distinction is made between remission off and on therapy: remission off therapy requires the patient to be on no other treatment for SLE than maintenance antimalarials; and remission on therapy allows patients to be on stable maintenance antimalarials, low-dose corticosteroids (prednisone ≤5 mg/day), maintenance immunosuppressives and/or maintenance biologics. The task force also agreed that the most appropriate outcomes (dependent variables) for testing the prognostic value (construct validity) of potential remission definitions are: death, damage, flares and measures of health-related quality of life. Conclusions The work of this international task force provides a framework for testing different definitions of remission against long-term outcomes

VARIAÇÕES MICROCLIMÁTICAS DE ÁREAS URBANAS EM BIOMAS NO ESTADO DE MATO GROSSO: CUIABÁ E SINOP

O estado de Mato Grosso, com extensão de 906 mil km², possui importância significativa devido a variedade de biomas, entre eles, Cerrado e floresta Amazônica. Sabe-se que a vegetação tem grande influência nas características microclimáticas locais. Exposto isso, o objetivo geral deste estudo foi analisar as variações microclimáticas de áreas urbanas nesses diferentes biomas do estado de Mato Grosso. Foram obtidos dados de radiação solar, temperatura do ar e umidade relativa do ar de estações microclimáticas fixas nos municípios de Cuiabá e Sinop, distantes entre si em 500 km, no ano de 2014. As variações de radiação solar, temperatura e umidade relativa do ar entre as áreas seguem a mesma sazonalidade. As temperaturas máximas ocorrem em setembro em ambas as cidades, enquanto as temperaturas mínimas ocorrem em julho para Cuiabá e junho para Sinop. Com relação a umidade relativa do ar média mensal, ambas possuem sua máxima em abril e mínima em agosto. As diferenças de energia solar incidente nas localidades, são maiores dentre junho e agosto devido as variações de nebulosidade e aerossóis presentes na atmosfera. Portanto a urbanização intensa do município de Cuiabá influencia diretamente nas condições climáticas do local