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Avaliação in vitro dos óleos essenciais e compostos majoritários de Lippia alba e Lippia gracilis sobre vermes adultos de Schistosoma mansoni

2022-05-20T00:15:15Z

Título: Avaliação in vitro dos óleos essenciais e compostos majoritários de Lippia alba e Lippia gracilis sobre vermes adultos de Schistosoma mansoni Autor(es): Gomes, Dharliton Soares Abstract: Schistosomiasis is a waterborne disease caused by trematodes of the genus Schistosoma. Of the most common species that parasitize humans, the most relevant are Schistosoma mansoni, Schistosoma japonicum and Schistosoma haematobium. Of these, S. mansoni is the trematode that causes schistosomiasis mansoni, being the only species found in Brazil. Chemotherapy is currently the most widely used method to combat schistosomiasis, with praziquantel (PZQ) being the drug recommended by the World Health Organization (WHO). Because it is a largescale medication in control programs and because it does not prevent reinfections, there is a concern about the emergence of resistant parasites. Some studies have already demonstrated the efficacy of some species of plants of the genus Lippia against various pathogenic parasites. In this sense, this work aims to evaluate the effect in vitro of essential oils (EOs) of L. alba and L. gracilis and their main components in adult worms of S. mansoni. The extraction of EOs from L. alba and L. gracilis was performed by means of hydrodistillation in a clevenger apparatus and their chemical composition determined by gas chromatography coupled to a mass spectrometer. Couples of adult worms were recovered from mice BALB/c previously infected with the LE strain of S. mansoni. The worms were distributed in 24-well culture plates containing supplemented RPMI-1640 and incubated (37ºC and 5% CO2) in concentrations of 100, 50, 25 and 5 µg/mL of essential oils and major compounds of L. alba and L. gracilis. The worms were monitored for 48 hours at intervals of 2, 4, 8, 24 and 48 hours to assess motility, mortality and oviposition under an inverted microscope. The cytotoxicity of OE and major compounds was evaluated by the MTT assay using mouse fibroblasts. The chemical characterization revealed that the EO of L. alba presents citral (49.97%) and limonene (18.53%) as major compounds, while carvacrol (32.29%), γ-terpinene (20.59%) and ρ-cymene (18.88%) were more abundant in the EO of L. gracilis. Among the tested EOs, L. gracilis was more active, causing a 100% reduction in the viability of worms exposed to concentrations of 100 and 50 µg/mL for 8h. Worms cultured for 24h in the presence of L. alba EO showed a reduction of approximately 60% in their viability at a concentration of 100 µg/mL. Regarding the major compounds, a 100% reduction in worm viability was observed with carvacrol at a concentration of 100µg / mL after 2h; on the other hand, citral reduced the viability of adult worms exposed to concentrations of 50 and 100 µg/mL by more than 75% after 24h. All EOs and their majorities reduced the oviposition of adult worms by more than 90%, even when exposed to a concentration (5 µg/mL) unable to reduce their motility or cause the worms to die. Both EOs proved to be non-toxic at the concentration of 50 µg/mL. The results stimulate future investigations of these plants as a potential source of bioactive compounds against S. mansoni.

Utilização do POC-CCA como diagnóstico, taxa de cura e reinfecção na infecção por Schistosoma mansoni em escolares em área de moderada endemicidade no Brasil

2022-05-19T22:07:49Z

Título: Utilização do POC-CCA como diagnóstico, taxa de cura e reinfecção na infecção por Schistosoma mansoni em escolares em área de moderada endemicidade no Brasil Autor(es): Costa, Mikael Ferreira Abstract: The Schistosoma mansoni is the disease-causing parasites of schistosomiasis, tropical disease neglected with great impact on morbidity and mortality in underdeveloped countries. The diagnosis method Kato-Katz is considered a benchmark test, however it has low sensitivity. Therefore, aiming to improve the disease diagnosis, the Point-of-care (POC) quick test that identifies circulating cathodic antigen (CCA) has been used as new form of identifying the disease. The POC-CCA comes with the proposal of being a method that consists of a quick mapping of positive cases, which can also be used to monitor the cure control and to reevaluate the reinfection of individuals, especially in endemic areas. Goal: To evaluate the prevalence of schistosomiasis in schoolchildren with POC-CCA as a diagnostic method and of tracking cure control in schoolchildren undergoing antiparasitic treatment. Methodology: Longitudinal epidemiological study, carried out with school-aged individuals (6-22 years old), in the municipality of Malhador/Sergipe in 5 endemic communities to schistosomiasis. The schoolchildren were diagnosed using the POC-CCA urine test, after the identification of the positives it was carried out the treatment with 133 pounds of Praziquantel. After 30 days of treatment it was made the collection of urine samples of treated individuals for the cure evaluation. Then, a year after treatment it was carried out the tracking to verify the reinfection rate of individuals who underwent the first treatment. Results: Were collected samples of 555 schoolchildren, 52% male and 48% female. Considering the trace as negative result, 112/555 (20,2%) had a positive diagnosis. However, if considering the trace as positive, increases the number of infected to 186/555 (33,5%) positive cases, this difference is shown to have p <0.001. Every individual with positive band in the diagnosis and treated (162) did the cure control 30 days after treatment 33/162 (t+) (20,4%) individuals kept positive in the exam by quick test. One year after treatment were tracked 129 schoolchildren, among which 43 (33,3%) were negative. CONCLUSION: The POC-CCA test shows to be a good diagnostic method of the infection by S. mansoni, also showing to be useful for quick epidemiological mapping, cure control and verification of the rate of reinfection.

Análise dos perfis séricos de citocinas e formação de clusters associados com as formas e complicações clínicas da hanseníase

2022-05-19T21:27:30Z

Título: Análise dos perfis séricos de citocinas e formação de clusters associados com as formas e complicações clínicas da hanseníase Autor(es): Cunha, Maria Wiliane do Nascimento Abstract: Leprosy is a chronic infectious disease with a slow clinical evolution, caused by the intracellular bacillus Mycobacterium leprae. This disease can be classified according to operational forms in paucibacillary and multibacillary, or according to histopathological criteria in the forms: indeterminate, tuberculoid, dimorphic and virchowian. In the clinical evolution of the disease, patients may present complications such as leprosy reactions and the occurrence of physical disability. The clinical manifestations and complications of leprosy are related to several factors such as the genetic background and immunological aspects inherent to the host. However, the exact role of cytokines in the characteristics of leprosy is still unclear. Therefore, the objective of this research was to investigate the role of cytokines in the complications and clinical forms of leprosy. 104 patients diagnosed with leprosy and their contact controls (n = 70) participated in the research. These were classified according to the clinical and operational form of the disease, as well as the occurrence of leprosy reaction and physical disability. After blood collection and serum separation, the dosage of cytokines of the profiles Th1, Th2, Treg, Th17, Th9 and Th22 produced by patients and contacts using the Luminex technique was observed. Statistical analyzes were performed using the Graphpad Prisma software and the cluster formation was performed using the R program (3.6.0). We observed that cytokines of inflammatory profile IL-12p70, IFN-y, TNF- α and IL-18 were related to the virchowian form, as well as being linked to the occurrence of leprosy and physical disability. The cytokines IL-17 and IL-22 was associated with the tuberculoid form. As for the cluster analysis, it was observed the formation of a cluster formed by the cytokines IFN-γ, TNF-α, IL-9, IL-5, IL-10 and IL18 that are involved with the main complications of leprosy. On the other hand, there was formation of the cluster composed of the cytokines IL-12p70, IL-1β, IL-23, IL-5, IL-2 and IL-17A in CC, this cluster may be related to an effective immune response against M. leprae. We conclude that cytokines of the Th1 profile (IFN-y, TNF-α e IL18) are involved with leprosy complications. In addition, we identified cytokines (TNFα, IL-18, IL-4, IL-6, IL-10 e IL-27) involved in the occurrence of leprosy complications, which can function as biomarkers for monitoring the clinical course of the disease.

Isolamento de Bacillus thuringiensis de amostra de solo e sua toxicidade sobre trofozoítos de Acanthamoeba castellanii

2022-05-19T00:41:41Z

Título: Isolamento de Bacillus thuringiensis de amostra de solo e sua toxicidade sobre trofozoítos de Acanthamoeba castellanii Autor(es): Santos, Edclecia Nascimento Abstract: Bacillus thuringiensis is a Gram-positive non-pathogenic spore-forming bacterium found in different habitats such as soils, plants, dead insects and marine sediments. This bacterium is the producer of several types of secondary metabolites with toxic activity, among them are the crystals of δ-endotoxin produced during sporulation. These proteins are called insecticidal crystal proteins (ICPs) and are distributed in two families: Cry and Cyt. Cry presents toxicity to a wide range of invertebrate organisms and also human cancer cells. B. thuringiensis is thus widely used as a bioinsecticide. Protozoa represent one of the target groups of these toxins, but with studies still scarce. The protozoan Acanthamoeba castellanii is a free-living amoeba, potentially pathogenic and causes diseases such as amoebic keratitis and granulomatous encephalitis amoebic, an illness difficult to diagnose and without specific drugs. This work aimed to isolate strains of B. thuringiensis from the soil and to characterize the Cry toxins encoded by them through toxicity tests against A. castellanii trophozoites. A total of 15 soil samples from different regions of the state were collected, and 150 bacillus like isolates were selected based on their morphological characteristics.After the analysis under microscope, 75 strains withgreater sporulation and presence of parasporal proteins were selected for bioassay. A total of three isolates 66, 69 and 75, showed high amebicidal activity against A. castellanii. After 48 h of interaction between protein and protozoa, the samples presented between 96.24 and 97.8% of cell death in the concentrations of 50 - 100 μg / mL. Under these conditions, the isolates presented IC50 values of 4.1, 4.35 and 8.3 μg/mL, respectively. Our results show that these proteins from B. thuringiensis exerts an amebicidal effect on trophozoites of A. castellanii. However it is necessary to carry out more specific studies so that these toxins can be used as medicine.