ATIVIDADE LEISHMANICIDA in vitro DE FRAÇÕES DO EXTRATO HIDROALCOÓLICO DAS FOLHAS DE Chenopodium ambrosioides L.

A leishmaniose é uma doença infecciosa causada por protozoários do gênero Leishmania e representa sério problema de saúde pública em paises da África, Ásia e América Latina. Chenopodium ambrosioides L.,  popularmente conhecido como mastruz, tem sido utilizado no Maranhão para o tratamento tópico de úlceras leishmanióticas. O trabalho avaliou a eficácia das frações do extrato hidroalcoólico das folhas de C. ambrosioides contra formas promastigotas da espécie Leishmania amazonensis. O fracionamento foi realizado pela partição sequencial do extrato hidroalcoólico de folhas de C. ambrosioides com solventes de polaridade crescente (hexano, clorofórmio e acetato de etila). As formas promastigotas foram cultivadas em meio RPMI 1640 com e sem as frações. Após 24h de incubação a 26ºC, o número de promastigotas viáveis foi contado pelo método direto em câmara de Neubauer. As concentrações que inibem o crescimento de 50% (CI50 ) das promastigotas de L. amazonensis foram calculadas a partir da avaliação da mortalidade das promastigotas in vitro. De acordo com escores padrões nas frações de acetato de etila e hidroalcoólica remanescente não foi observada atividade leishmanicida significativa, mas as frações hexânica e clorofórmica apresentaram-se ativas. Os resultados obtidos demonstram uma ação leishmanicida promissora das frações. Estudos futuros são necessários para investigar a eficácia destas frações no tratamento da leishmaniose em modelos experimentais in vivo.Descritores: Chenopodium ambrosioides L.; Mastruz; Leishmaniose; in vitro. Abstract:  In vitro leishmanicidal activity of fractions obtained from hydroalcoholic extracts of  Chenopodium ambrosioides’  leaves. Leishmaniasis is an infectious disease caused by protozoa of the genus Leishmania and represents serious public health problem in Africa, Asia and Latin America. Chenopodium ambrosioides, popularly known as “mastruz”, has been used in Maranhão for the topical treatment of leishmanial ulcers. The study evaluated the effectiveness of the fractions from hydroalcoholic extract of C. ambrosioides’  leaves against the promastigotes of Leishmania amazonensis. Fractionation as accomplished by partition sequential extract of leaves of C. ambrosioides with solvents of increasing polarity (hexane, chloroform and ethyl acetate). The promastigotes forms were cultured in supplemented RPMI 1640 with or without fractions. After 24h incubation at 26°C, the number of viable promastigotes was counted by the direct method in a Neubauer chamber. The concentrations that inhibit growth of 50% (IC50 ) of L. amazonensis’ promastigotes were calculated from the assessment of the mortality of promastigotes in vitro. According to standard scores, in the ethyl acetate and hydroalcoholic remaining fractions there was no leishmanicidal activity, while the hexane and chloroform fractions were actives. The results showed a promissor leishmanicidal activity of fraction. Future studies are necessary to investigate the effectiveness of these fractions in the treatment of these fractions in experimental models in vivo.Descriptors: Chenopodium ambrosioides L.; Mastruz; Leishmaniasis; in vitro

Activation of cannabinoid type 1 receptor (CB1) modulates oligodendroglial process branching complexity in rat hippocampal cultures stimulated by olfactory ensheathing glia-conditioned medium

The endocannabinoid system (ECS) refers to a complex cell-signaling system highly conserved among species formed by numerous receptors, lipid mediators (endocannabinoids) and synthetic and degradative enzymes. It is widely distributed throughout the body including the CNS, where it participates in synaptic signaling, plasticity and neurodevelopment. Besides, the olfactory ensheathing glia (OEG) present in the olfactory system is also known to play an important role in the promotion of axonal growth and/or myelination. Therefore, both OEG and the ECS promote neurogenesis and oligodendrogenesis in the CNS. Here, we investigated if the ECS is expressed in cultured OEG, by assessing the main markers of the ECS through immunofluorescence, western blotting and qRT-PCR and quantifying the content of endocannabinoids in the conditioned medium of these cells. After that, we investigated whether the production and release of endocannabinoids regulate the differentiation of oligodendrocytes co-cultured with hippocampal neurons, through Sholl analysis in oligodendrocytes expressing O4 and MBP markers. Additionally, we evaluated through western blotting the modulation of downstream pathways such as PI3K/Akt/mTOR and ERK/MAPK, being known to be involved in the proliferation and differentiation of oligodendrocytes and activated by CB1, which is the major endocannabinoid responsive receptor in the brain. Our data show that OEG expresses key genes of the ECS, including the CB1 receptor, FAAH and MAGL. Besides, we were able to identify AEA, 2-AG and AEA related mediators palmitoylethanolamide (PEA) and oleoylethanolamide (OEA), in the conditioned medium of OEG cultures. These cultures were also treated with URB597 10-9 M, a FAAH selective inhibitor, or JZL184 10-9 M, a MAGL selective inhibitor, which led to the increase in the concentrations of OEA and 2-AG in the conditioned medium. Moreover, we found that the addition of OEG conditioned medium (OEGCM) enhanced the complexity of oligodendrocyte process branching in hippocampal mixed cell cultures and that this effect was inhibited by AM251 10-6 M, a CB1 receptor antagonist. However, treatment with the conditioned medium enriched with OEA or 2-AG did not alter the process branching complexity of premyelinating oligodendrocytes, while decreased the branching complexity in mature oligodendrocytes. We also observed no change in the phosphorylation of Akt and ERK 44/42 in any of the conditions used. In conclusion, our data show that the ECS modulates the number and maturation of oligodendrocytes in hippocampal mixed cell cultures

Pervasive gaps in Amazonian ecological research

Biodiversity loss is one of the main challenges of our time,1,2 and attempts to address it require a clear un derstanding of how ecological communities respond to environmental change across time and space.3,4 While the increasing availability of global databases on ecological communities has advanced our knowledge of biodiversity sensitivity to environmental changes,5–7 vast areas of the tropics remain understudied.8–11 In the American tropics, Amazonia stands out as the world’s most diverse rainforest and the primary source of Neotropical biodiversity,12 but it remains among the least known forests in America and is often underrepre sented in biodiversity databases.13–15 To worsen this situation, human-induced modifications16,17 may elim inate pieces of the Amazon’s biodiversity puzzle before we can use them to understand how ecological com munities are responding. To increase generalization and applicability of biodiversity knowledge,18,19 it is thus crucial to reduce biases in ecological research, particularly in regions projected to face the most pronounced environmental changes. We integrate ecological community metadata of 7,694 sampling sites for multiple or ganism groups in a machine learning model framework to map the research probability across the Brazilian Amazonia, while identifying the region’s vulnerability to environmental change. 15%–18% of the most ne glected areas in ecological research are expected to experience severe climate or land use changes by 2050. This means that unless we take immediate action, we will not be able to establish their current status, much less monitor how it is changing and what is being lostinfo:eu-repo/semantics/publishedVersio

Pervasive gaps in Amazonian ecological research

Biodiversity loss is one of the main challenges of our time,1,2 and attempts to address it require a clear understanding of how ecological communities respond to environmental change across time and space.3,4 While the increasing availability of global databases on ecological communities has advanced our knowledge of biodiversity sensitivity to environmental changes,5,6,7 vast areas of the tropics remain understudied.8,9,10,11 In the American tropics, Amazonia stands out as the world's most diverse rainforest and the primary source of Neotropical biodiversity,12 but it remains among the least known forests in America and is often underrepresented in biodiversity databases.13,14,15 To worsen this situation, human-induced modifications16,17 may eliminate pieces of the Amazon's biodiversity puzzle before we can use them to understand how ecological communities are responding. To increase generalization and applicability of biodiversity knowledge,18,19 it is thus crucial to reduce biases in ecological research, particularly in regions projected to face the most pronounced environmental changes. We integrate ecological community metadata of 7,694 sampling sites for multiple organism groups in a machine learning model framework to map the research probability across the Brazilian Amazonia, while identifying the region's vulnerability to environmental change. 15%–18% of the most neglected areas in ecological research are expected to experience severe climate or land use changes by 2050. This means that unless we take immediate action, we will not be able to establish their current status, much less monitor how it is changing and what is being lost

Mortality from gastrointestinal congenital anomalies at 264 hospitals in 74 low-income, middle-income, and high-income countries: a multicentre, international, prospective cohort study

Summary Background Congenital anomalies are the fifth leading cause of mortality in children younger than 5 years globally. Many gastrointestinal congenital anomalies are fatal without timely access to neonatal surgical care, but few studies have been done on these conditions in low-income and middle-income countries (LMICs). We compared outcomes of the seven most common gastrointestinal congenital anomalies in low-income, middle-income, and high-income countries globally, and identified factors associated with mortality. Methods We did a multicentre, international prospective cohort study of patients younger than 16 years, presenting to hospital for the first time with oesophageal atresia, congenital diaphragmatic hernia, intestinal atresia, gastroschisis, exomphalos, anorectal malformation, and Hirschsprung’s disease. Recruitment was of consecutive patients for a minimum of 1 month between October, 2018, and April, 2019. We collected data on patient demographics, clinical status, interventions, and outcomes using the REDCap platform. Patients were followed up for 30 days after primary intervention, or 30 days after admission if they did not receive an intervention. The primary outcome was all-cause, in-hospital mortality for all conditions combined and each condition individually, stratified by country income status. We did a complete case analysis. Findings We included 3849 patients with 3975 study conditions (560 with oesophageal atresia, 448 with congenital diaphragmatic hernia, 681 with intestinal atresia, 453 with gastroschisis, 325 with exomphalos, 991 with anorectal malformation, and 517 with Hirschsprung’s disease) from 264 hospitals (89 in high-income countries, 166 in middleincome countries, and nine in low-income countries) in 74 countries. Of the 3849 patients, 2231 (58·0%) were male. Median gestational age at birth was 38 weeks (IQR 36–39) and median bodyweight at presentation was 2·8 kg (2·3–3·3). Mortality among all patients was 37 (39·8%) of 93 in low-income countries, 583 (20·4%) of 2860 in middle-income countries, and 50 (5·6%) of 896 in high-income countries (p<0·0001 between all country income groups). Gastroschisis had the greatest difference in mortality between country income strata (nine [90·0%] of ten in lowincome countries, 97 [31·9%] of 304 in middle-income countries, and two [1·4%] of 139 in high-income countries; p≤0·0001 between all country income groups). Factors significantly associated with higher mortality for all patients combined included country income status (low-income vs high-income countries, risk ratio 2·78 [95% CI 1·88–4·11], p<0·0001; middle-income vs high-income countries, 2·11 [1·59–2·79], p<0·0001), sepsis at presentation (1·20 [1·04–1·40], p=0·016), higher American Society of Anesthesiologists (ASA) score at primary intervention (ASA 4–5 vs ASA 1–2, 1·82 [1·40–2·35], p<0·0001; ASA 3 vs ASA 1–2, 1·58, [1·30–1·92], p<0·0001]), surgical safety checklist not used (1·39 [1·02–1·90], p=0·035), and ventilation or parenteral nutrition unavailable when needed (ventilation 1·96, [1·41–2·71], p=0·0001; parenteral nutrition 1·35, [1·05–1·74], p=0·018). Administration of parenteral nutrition (0·61, [0·47–0·79], p=0·0002) and use of a peripherally inserted central catheter (0·65 [0·50–0·86], p=0·0024) or percutaneous central line (0·69 [0·48–1·00], p=0·049) were associated with lower mortality. Interpretation Unacceptable differences in mortality exist for gastrointestinal congenital anomalies between lowincome, middle-income, and high-income countries. Improving access to quality neonatal surgical care in LMICs will be vital to achieve Sustainable Development Goal 3.2 of ending preventable deaths in neonates and children younger than 5 years by 2030

Cannabinoid Receptor Type 1 Expression in the Developing Avian Retina: Morphological and Functional Correlation With the Dopaminergic System

The avian retina has been used as a model to study signaling by different neuro- and gliotransmitters. It is unclear how dopaminergic and cannabinoid systems are related in the retina. Here we studied the expression of type 1 and 2 cannabinoid receptors (CB1 and CB2), as well as monoacylglycerol lipase (MAGL), the enzyme that degrades 2-arachidonoylglycerol (2-AG), during retina development. Our data show that CB1 receptor is highly expressed from embryonic day 5 (E5) until post hatched day 7 (PE7), decreasing its levels throughout development. CB1 is densely found in the ganglion cell layer (GCL) and inner plexiform layer (IPL). CB2 receptor was also found from E5 until PE7 with a decrease in its contents from E9 afterwards. CB2 was mainly present in the lamination of the IPL at PE7. MAGL is expressed in all retinal layers, mainly in the IPL and OPL from E9 to PE7 retina. CB1 and CB2 were found both in neurons and glia cells, but MAGL was only expressed in Müller glia. Older retinas (PE7) show CB1 positive cells mainly in the INL and co-expression of CB1 and tyrosine hydroxylase (TH) are shown in a few cells when both systems are mature. CB1 co-localized with TH and was heavily associated to D1 receptor labeling in primary cell cultures. Finally, cyclic AMP (cAMP) was activated by the selective D1 agonist SKF38393, and inhibited when cultures were treated with WIN55, 212–2 (WIN) in a CB1 dependent manner. The results suggest a correlation between the endocannabinoid and dopaminergic systems (DSs) during the avian retina development. Activation of CB1 limits cAMP accumulation via D1 receptor activation and may influence embryological parameters during avian retina differentiation

Polymorphisms in B Cell Co-Stimulatory Genes Are Associated with IgG Antibody Responses against Blood–Stage Proteins of <i>Plasmodium vivax</i>

<div><p>The development of an effective immune response can help decrease mortality from malaria and its clinical symptoms. However, this mechanism is complex and has significant inter-individual variation, most likely owing to the genetic contribution of the human host. Therefore, this study aimed to investigate the influence of polymorphisms in genes involved in the costimulation of B-lymphocytes in the naturally acquired humoral immune response against proteins of the asexual stage of <i>Plasmodium vivax</i>. A total of 319 individuals living in an area of malaria transmission in the Brazilian Amazon were genotyped for four SNPs in the genes <i>CD40</i>, <i>CD40L</i>, <i>BLYS</i> and <i>CD86</i>. In addition, IgG antibodies against <i>P</i>. <i>vivax</i> apical membrane antigen 1 (PvAMA–1), Duffy binding protein (PvDBP) and merozoite surface protein 1 (PvMSP–1₁₉) were detected by ELISA. The SNP <i>BLYS</i> –871C>T was associated with the frequency of IgG responders to PvAMA–1 and PvMSP–1₁₉. The SNP <i>CD40</i> –1C>T was associated with the IgG response against PvDBP, whereas IgG antibody titers against PvMSP–1₁₉ were influenced by the polymorphism <i>CD86</i> +1057G>A. These data may help to elucidate the immunological aspects of vivax malaria and consequently assist in the design of malaria vaccines.</p></div