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Abstract Frugivore bats are important seed dispersers in forests and their abundance are associated with the presence of zoochoric plants. In this context, the aim of our study was to investigate the association of the frugivore bat S. lilium with the diaspores of the zoochoric plant S. mauritianum, a common arboreal species present in forest fragments of southern Brazil. We also investigated the diet of the species based on seed content present in feces of individuals. Bats were mist-netted from November 2017 to April 2018 in a fragment of Atlantic Forest. The proportion of immature and mature diaspores of S. mauritianum was estimated in the same area where bats were sampled, and feces were sampled from captured individuals. In total, 61 individuals of S. lilium were captured, and 795 seeds were sampled from their feces. The abundance of S. lilium was significantly associated with the proportion of immature diaspores of S. mauritianum. We identified seeds of two botanical families: Solanaceae (89%) and Moraceae (11%) in the fecal samples. Our findings support the view that S. lilium is a legitimate disperser of S. mauritianum, and that its ecological function is probably a result of co-adaptation.

The development of new treatments for neglected tropical diseases (NTDs) remains a major challenge in the 21st century. In most cases, the available drugs are obsolete and have limitations in terms of efficacy and safety. The situation becomes even more complex when considering the low number of new chemical entities (NCEs) currently in use in advanced clinical trials for most of these diseases. Natural products (NPs) are valuable sources of hits and lead compounds with privileged scaffolds for the discovery of new bioactive molecules. Considering the relevance of biodiversity for drug discovery, a chemoinformatics analysis was conducted on a compound dataset of NPs with anti-trypanosomatid activity reported in 497 research articles from 2019 to 2024. Structures corresponding to different metabolic classes were identified, including terpenoids, benzoic acids, benzenoids, steroids, alkaloids, phenylpropanoids, peptides, flavonoids, polyketides, lignans, cytochalasins, and naphthoquinones. This unique collection of NPs occupies regions of the chemical space with drug-like properties that are relevant to anti-trypanosomatid drug discovery. The gathered information greatly enhanced our understanding of biologically relevant chemical classes, structural features, and physicochemical properties. These results can be useful in guiding future medicinal chemistry efforts for the development of NP-inspired NCEs to treat NTDs caused by trypanosomatid parasites.

Abstract Background Previous studies challenge the impact of obstructive sleep apnea (OSA) once patients are diagnosed with Alzheimer’s disease (AD). Nevertheless, OSA recognizably disrupts sleep, and relevant associations between sleep, AD pathological markers, and cognition have been demonstrated. We aimed to further explore this, evaluating the associations between each breathing cessation event that compose the apnea–hypopnea index (AHI) and the sleep structure to finally investigate whether this was related to increased levels of AD markers and higher cognitive decline. Methods Observational, prospective study, including consecutive patients diagnosed with mild-moderate AD. The participants were submitted to overnight polysomnography followed by a cerebrospinal fluid collection for AD pathological markers levels determination. Neuropsychological assessment was performed at baseline and after 12 months of follow-up. Results The cohort was composed of 116 patients (55.2% females) with a median [p25;p75] age of 76.0 [72.0;80.0] years and an AHI of 25.9 [15.1;48.5], which was mainly defined by the presence of hypopneas and obstructive apneas. These were distinctively associated with the sleep structure, with obstructive apneas being related to arousals and sleep lightening and hypopneas being related to an increased number of arousals only. Despite having a lower frequency, mixed and central apneas also presented associations with the sleep structure, particularly increasing the time spent in the lighter sleep stages. In relation to AD pathological markers, obstructive and mixed apneas were related to an augment in neurofilament light levels while hypopneas were associated with a higher phosphorylated-tau/amyloid-beta protein ratio. Hypopneas were the most important event for an increased cognitive decline at the 12-month follow-up. Conclusions Our findings highlight the importance of a patient-centered approach, with a comprehensive and detailed analysis of the AHI to effectively predict the different outcomes and tailor the appropriate therapeutic strategies.

The number of databases of natural products (NPs) has increased substantially. Latin America is extraordinarily rich in biodiversity, enabling the identification of novel NPs, which has encouraged both the development of databases and the implementation of those that are being created or are under development. In a collective effort from several Latin American countries, herein we introduce the first version of the Latin American Natural Products Database (LANaPDB), a public compound collection that gathers the chemical information of NPs contained in diverse databases from this geographical region. The current version of LANaPDB unifies the information from six countries and contains 12,959 chemical structures. The structural classification showed that the most abundant compounds are the terpenoids (63.2%), phenylpropanoids (18%) and alkaloids (11.8%). From the analysis of the distribution of properties of pharmaceutical interest, it was observed that many LANaPDB compounds satisfy some drug-like rules of thumb for physicochemical properties. The concept of the chemical multiverse was employed to generate multiple chemical spaces from two different fingerprints and two dimensionality reduction techniques. Comparing LANaPDB with FDA-approved drugs and the major open-access repository of NPs, COCONUT, it was concluded that the chemical space covered by LANaPDB completely overlaps with COCONUT and, in some regions, with FDA-approved drugs. LANaPDB will be updated, adding more compounds from each database, plus the addition of databases from other Latin American countries.

Abstract Background Alterations in circadian rhythms are present in the presymptomatic stage of Alzheimer’s disease (AD), possibly contributing to its pathogenesis. However, it is unknown whether such alterations are associated with worse outcomes once individuals are diagnosed with symptomatic disease. We aimed to evaluate the association between the circadian rest-activity pattern and AD-related features in patients with mild-moderate AD. Methods We assessed the circadian rest-activity pattern of consecutive patients with mild-moderate AD through actigraphy for 14 days. Cerebrospinal fluid was obtained to determine the levels of important pathological markers including amyloid-beta protein (Aβ42), phosphorylated tau (P-tau), total tau (T-tau), and neurofilament light (NF-L). Neuropsychological evaluation was conducted at the beginning of the study and after 12 months of follow-up. Linear regression models were performed considering the global population and Aβ42+ patients only. Results The cohort included 100 patients with mild-moderate AD. The median age [p25;p75] was 76.0 [73.0;80.0] years and 63.0% were female. Older age (effect size [SE] of 0.324 [0.096]; p = 0.001) and male sex (0.780 [0.193]; p = 0.001) were associated with increased fragmentation and decreased synchronization of the rhythm, respectively. After adjusting for age, sex, and season of the year, increased levels of T-tau (effect size [95% CI] of 0.343 [0.139 to 0.547]; p = 0.001) and NF-L (0.444 [0.212 to 0.676]; p = 0.001) were associated with a higher amplitude of the rest-activity rhythm. Increased fragmentation of the rhythm at baseline was associated with greater cognitive decline after one year of follow-up independent of age, sex, T-tau/Aβ42 ratio, educational level, and season of the year (− 0.715 [− 1.272 to − 0.157]; p = 0.013). Similar findings were obtained considering only the Aβ42+ patients. Conclusions Our results suggest a potential role of the circadian rest-activity pattern in predicting the cognitive decline of patients with mild-moderate AD. Further studies are warranted to confirm these findings and to elucidate whether there is causality among the observed associations.

The development of new treatments for neglected tropical diseases (NTDs) remains a major challenge in the 21st century. In most cases, the available drugs are obsolete and have limitations in terms of efficacy and safety. The situation becomes even more complex when considering the low number of new chemical entities (NCEs) currently in use in advanced clinical trials for most of these diseases. Natural products (NPs) are valuable sources of hits and lead compounds with privileged scaffolds for the discovery of new bioactive molecules. Considering the relevance of biodiversity for drug discovery, a chemoinformatics analysis was conducted on a compound dataset of NPs with anti-trypanosomatid activity reported in 497 research articles from 2019 to 2024. Structures corresponding to different metabolic classes were identified, including terpenoids, benzoic acids, benzenoids, steroids, alkaloids, phenylpropanoids, peptides, flavonoids, polyketides, lignans, cytochalasins, and naphthoquinones. This unique collection of NPs occupies regions of the chemical space with drug-like properties that are relevant to anti-trypanosomatid drug discovery. The gathered information greatly enhanced our understanding of biologically relevant chemical classes, structural features, and physicochemical properties. These results can be useful in guiding future medicinal chemistry efforts for the development of NP-inspired NCEs to treat NTDs caused by trypanosomatid parasites. [ABSTRACT FROM AUTHOR]

Compound databases of natural products play a crucial role in drug discovery and development projects and have implications in other areas, such as food chemical research, ecology and metabolomics. Recently, we put together the first version of the Latin American Natural Product database (LANaPDB) as a collective effort of researchers from six countries to ensemble a public and representative library of natural products in a geographical region with a large biodiversity. The present work aims to conduct a comparative and extensive profiling of the natural product‐likeness of an updated version of LANaPDB and the individual ten compound databases that form part of LANaPDB. The natural product‐likeness profile of the Latin American compound databases is contrasted with the profile of other major natural product databases in the public domain and a set of small‐molecule drugs approved for clinical use. As part of the extensive characterization, we employed several chemoinformatics metrics of natural product likeness. The results of this study will capture the attention of the global community engaged in natural product databases, not only in Latin America but across the world. [ABSTRACT FROM AUTHOR]

Introduction and Objectives: The Stents Coated With the Biodegradable Polymer on Their Abluminal Faces and Elution of Sirolimus Versus Biolimus Elution for the Treatment of de Novo Coronary Lesions – DESTINY Trial is a non-inferiority randomized study that compared the Inspiron™ sirolimus-eluting stent (SES) with the control Biomatrix™ Flex biolimus-eluting stent (BES). Previous reports in the first year showed similar outcomes for both stents, in clinical, angiographic, optical coherence tomography, and intravascular ultrasound assessments. The present analysis aims to compare the clinical performance of these two biodegradable polymer drug-eluting stents five years after the index procedure. Methods: A total of 170 patients (194 lesions) were randomized in a 2:1 ratio for treatment with SES or BES, respectively. The primary endpoint for the present study was the five-year rate of combined major adverse cardiac events, defined as cardiac death, myocardial infarction, or target lesion revascularization. Results: At five years, the primary endpoint occurred in 12.5% and 17.9% of the SES and BES groups, respectively (p=0.4). There was no definite or probable stent thrombosis among patients treated with the novel SES stent during the five years of follow-up, and no stent thrombosis after the first year in the BES group. Conclusions: The novel Inspiron™ stent had similar good clinical performance in long-term follow-up when compared head-to-head with the control latest-generation Biomatrix™ Flex biolimus-eluting stent. Resumo: Introdução e objetivos: Stents Coated with the Biodegradable Polymer on their Abluminal Faces and Elution of Sirolimus Versus Biolimus Elution for the Treatment of de Novo Coronary Lesions (Destiny Trial) é um estudo randomizado de não inferioridade que comparou o stent farmacológico eluído com Sirolimus Inspiron® (SES) ao controle o stent Biomatrix® Flex eluído com biolimus (BES). Relatórios dentro do primeiro ano mostraram resultados semelhantes para ambos os stents, em seguimento clínico, angiográfico e também em análise de tomografia de coerência ótica e ultrassom intracoronário. A presente análise tem como objetivo comparar o desempenho clínico desses dois stents farmacológicos com polímeros biodegradáveis após cinco anos do procedimento índice. Métodos: Foram randomizados 170 pacientes (194 lesões) em uma proporção de 2:1 para tratamento com SES ou BES, respetivamente. O desfecho primário para o presente estudo foi a taxa em cinco anos de eventos cardíacos adversos maiores combinados, definida como morte cardíaca, infarto do miocárdio ou revascularização da lesão-alvo. Resultados: Em cinco anos, o desfecho primário ocorreu em 12,5% e 17,9% para o grupo SES e BES, respectivamente (p=0,4). Não houve trombose de stent definitiva ou provável entre os pacientes tratados com o novo SES durante os cinco anos de seguimento e ausência de trombose de stent após o primeiro ano no grupo BES. Conclusões: O novo stent Inspiron® apresentou uma boa e semelhante performance clínica no seguimento em longo prazo, quando comparado com o controle o stent de última geração Biomatrix® Flex.

Human helminthiasis affects approximately one in five people in the world and disproportionally affects the poorest and most deprived communities. Human angiostrongyliasis, caused by nematode Angiostrongylus cantonensis, is a neglected emerging disease with escalating importance worldwide. Chemotherapy is the main control method for helminthiasis, but the therapeutic arsenal is limited. This study aimed to evaluate the antiparasitic and molecular properties of the major available anthelmintic drugs against A. cantonensis in vitro. The first-stage larvae (L1), isolated from feces of an A. cantonensis-infected rat, were exposed to a set of 12 anthelmintic drugs in vitro. The larvae were monitored, and the concentration- and time-dependent viability alterations were determined. From 12 anthelmintic drugs, six (ivermectin, salamectin, moxidectin, pyrantel pamoate, albendazole and levamisole) were identified to affect the viability of A. cantonensis. The macrocyclic lactones (ivermectin, salamectin, moxidectin) and the imidazothiazole levamisole, were the most effective drugs, with IC50 ranging from 2.2 to 2.9 µM and a rapid onset of action. Albendazole, the most widely used anthelmintic in humans, had a slower onset of action, but an IC50 of 11.3 µM was achieved within 24 h. Molecular properties studies suggest that a less lipophilic character and low molecular weight could be favorable for the biological activity of the non-macrocyclic molecules. Collectively, our study revealed that macrocyclic lactones, levamisole, pyrantel pamoate, and albendazole are important anthelmintic agents against A. cantonensis. The results of this in vitro study also suggest that A. cantonensis L1 may be a particularly sensitive and useful model for anthelmintic studies.

resumo Existem no mundo cerca de 2.000 registros de ensaios clínicos para a investigação de medicamentos aprovados e outros candidatos para a Covid-19, incluindo moléculas pequenas e medicamentos biológicos, sem contar as vacinas. O reposicionamento de fármacos, estratégia mais explorada até o momento, não levou a qualquer novo tratamento antiviral contra a Covid-19. O remdesivir, apesar de sua aprovação emergencial pela agência reguladora norte-americana, apresentou somente resultados modestos em estudos clínicos. A dexametasona, que contribuiu para reduzir a mortalidade em pacientes graves recebendo ventilação mecânica invasiva ou oxigênio, é um corticoide que possui propriedades anti-inflamatórias e imunossupressoras. Os medicamentos biológicos, por sua vez, como anticorpos monoclonais, interferons, proteínas específicas e anticoagulantes estão sendo avaliados em diversas triagens clínicas para definir o seu papel na terapia da doença. A Organização Mundial da Saúde (OMS) alertou que o coronavírus poderá nunca desaparecer, mesmo com uma eventual vacina, evidenciando a urgência de pesquisas por novos fármacos inovadores. O cenário atual mais realista compreende o desenvolvimento de antivirais específicos contra o Sars-CoV-2 para o tratamento seguro e eficaz da doença.

Abstract 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.

Cruzain, the main cysteine protease of Trypanosoma cruzi, plays key roles in all stages of the parasite’s life cycle, including nutrition acquisition, differentiation, evasion of the host immune system, and invasion of host cells. Thus, inhibition of this validated target may lead to the development of novel drugs for the treatment of Chagas disease. In this study, a multiparameter optimization (MPO) approach, molecular modeling, and structure-activity relationships (SARs) were employed for the identification of new benzimidazole derivatives as potent competitive inhibitors of cruzain with trypanocidal activity and suitable pharmacokinetics. Extensive pharmacokinetic studies enabled the identification of metabolically stable and permeable compounds with high selectivity indices. CYP3A4 was found to be involved in the main metabolic pathway, and the identification of metabolic soft spots provided insights into molecular optimization. Compound 28, which showed a promising trade-off between pharmacodynamics and pharmacokinetics, caused no acute toxicity and reduced parasite burden both in vitro and in vivo.

Habitat loss is one of the main consequences of landscape transformation by humans. Monitoring biodiversity changes in areas under different management strategies is fundamental for species conservation. Our study is the first to assess the role of forest disturbance history on spider (Araneae) biodiversity in the westernmost portion of the Atlantic Forest. We analyzed taxonomic and functional aspects of spider assemblages in understories in a large forest fragment in southwestern Brazil. Spiders were sampled in five 30 m x 5 m plots over three seasons in three areas with different management histories: clearcutting, selective logging, or native plots. We also characterized tree basal area, tree density, and canopy openness. The clear-cut plots showed more canopy openness and low habitat heterogeneity due to the high density of one pioneer native tree species. Forest structure in selective logging and native plots was similar. Spider richness, abundance, and functional richness were affected only by the season. Species composition also differed among the areas depending on the season. The abundance of web-building species was mainly associated with clear-cut areas in winter and spring. These results highlight the importance of natural regeneration in the Atlantic Forest after disturbance for the conservation of regional spider biodiversity. Key words: richness, abundance, community composition, selective logging, seasonal effect. La perte d'habitat est une des principales consequences de la transformation des paysages par l'homme. Le suivi des changements dans la biodiversite des zones soumises a differentes strategies d'amenagement est fondamental pour la conservation des especes. Notre etude est la premiere a evaluer le role de l'historique des perturbations de la foret sur la biodiversite des araignees (Araneae) dans la portion la plus occidentale de la foret atlantique bresilienne. Nous avons analyse les aspects taxonomique et fonctionnel des assemblages d'araignees dans les sous-bois d'une vaste portion de foret dans le sud- ouest du Bresil. Les araignees ont ete echantillonnees dans cinq parcelles de 30 m x 5 m pendant trois saisons, a trois endroits ayant differents historiques d'amenagement: coupe a blanc, coupe selective et parcelle non amenagee. Nous avons aussi caracterise la surface terriere et la densite des arbres ainsi que l'ouverture du couvert forestier. Le couvert forestier etait plus ouvert et l'heterogeneite de l'habitat etait plus faible dans les parcelles coupees a blanc a cause de la forte densite d'une essence pionniere indigene. La structure de la foret etait similaire dans les parcelles ayant subi une coupe selective et dans les parcelles non amenagees. Seule la saison avait un impact sur la richesse, l'abondance et la richesse fonctionnelle des araignees. La composition en especes aussi differait parmi les endroits selon la saison. L'abondance des especes qui tissent des toiles etait principalement associee aux parcelles coupees a blanc durant l'hiver et le printemps. Ces resultats font ressortir l'importance de la regeneration naturelle dans la foret atlantique bresilienne pour la conservation de la biodiversite regionale des araignees apres une perturbation. [Traduit par la Redaction] Mots-cles: richesse, abondance, composition de la communaute, coupe selective, effet saisonnier., Introduction Biodiversity conservation is among the greatest challenges that the scientific community is facing today because of increasing anthropogenic disturbance in natural ecosystems worldwide. Habitat loss, one of the main [...]

The synthesis and antioxidant, antinociceptive and antiedematogenic activities of sulfonamides derived from carvacrol—a druglike natural product—are reported. The compounds showed promising antioxidant activity, and sulfonamide derived from morpholine (S1) demonstrated excellent antinociceptive and antiedematogenic activities, with no sedation or motor impairment. The mechanism that underlies the carvacrol and derived sulfonamides’ relieving effects on pain has not yet been fully elucidated, however, this study shows that the antinociceptive activity can be partially mediated by the antagonism of glutamatergic signaling. Compound S1 presented promising efficacy and was predicted to have an appropriate medicinal chemistry profile. Thus, derivative S1 is an interesting starting point for the design of new leads for the treatment of pain and associated inflammation and prooxidative conditions.

Background: Treatment and control of schistosomiasis, one of the most insidious and serious parasitic diseases, depend almost entirely on a single drug, praziquantel. Since the funding for drug development for poverty-associated diseases is very limited, drug repurposing is a promising strategy. In this study, 73 nonsteroidal anti-inflammatory drugs (NSAIDs) commonly used in medical and veterinary fields were evaluated for their anti-schistosomal properties. Methods: The efficacy of NSAIDs was first tested against adult Schistosoma mansoni ex vivo using phenotypic screening strategy, effective drugs were further tested in a murine model of schistosomiasis. The disease parameters measured were worm and egg burden, hepato- and splenomegaly. Findings: From 73 NSAIDs, five (mefenamic acid, tolfenamic acid, meclofenamic acid, celecoxib, and diclofenac) were identified to effectively kill schistosomes. These results were further supported by scanning electron microscopy analysis. In addition, the octanol-water partition coefficient, both for neutral and ionized species, revealed to be a critical property for the ex vivo activity profile. Compounds were then tested in vivo using both patent and a prepatent S. mansoni infection in a mouse model. The most effective NSAID was mefenamic acid, which highly reduced worm burden, egg production, and hepato- and splenomegaly. Interpretation: The treatment regimen used in this study is within the range for which mefenamic acid has been used in clinical practice, thus, it is demonstrated the capacity of mefenamic acid to act as a potent anti-schistosomal agent suitable for clinical repurposing in the treatment of schistosomiasis. Keywords: Schistosomiasis, Nonsteroidal anti-inflammatory drugs, Mefenamic acid, Anthelmintic, Schistosomicidal activity