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We increase the dynamical range of a scanning tunneling microscope (STM) by actively subtracting dominant current-harmonics generated by nonlinearities in the current-voltage characteristics that could saturate the current preamplifier at low junction impedances or high gains. The strict phase relationship between a cosinusoidal excitation voltage and the current-harmonics allows excellent cancellation using the displacement-current of a driven compensating capacitor placed at the input of the preamplifier. Removal of DC currents has no effect on, and removal of the first harmonic only leads to a rigid shift in differential conductance that can be numerically reversed by adding the known removal current. Our method requires no permanent change of the hardware but only two phase synchronized voltage sources and a multi-frequency lock-in amplifier to enable high dynamic range spectroscopy and imaging. ⢠Active power filter ⢠Dynamic range compression ⢠High gain preamplifier.
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Sedation is a depression of a patient's state of consciousness, induced by medications, that can reach different levels of intensity during a medical procedure. Conscious sedation produces a minimally depressed level of consciousness without impairment of the ability to maintain an open airway, of protective reflexes or of responses to verbal and physical stimulation. This umbrella review is aimed at critically assessing the available systematic reviews (SRs) and meta-analyses (MA) on sedation in children/adolescents. An electronic database search was conducted that included Pubmed-Medline, Web of Science, Cochrane, Scopus, Scielo, Embase, LILACS and TRIP and the scope of which extended until January 2023. The risk of bias (RoB) of SRs was analyzed using the Measurement Tool to Assess SRs criteria 2 (AMSTAR2). Of 998 entries, 37 SRs were included. In terms of methodological quality, eight studies were assessed as having critically low quality, four studies had low quality, nine studies had moderate quality, and sixteen were considered to be of high quality. Based on the current guidelines, the most employed drugs in pediatric dentistry for sedation are nitrous oxide and midazolam; however, the available evidence supporting their use is insufficient and of low/critically low quality. The combined technique is recommended (nitrous oxide (30-50%) + midazolam). The optimal dose of oral midazolam is 0.75 mg/kg. The level of methodological quality of SRs is expected to increase according to the results and future directions of this umbrella review.
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INTRODUCTION: Triple- and quad-refractory multiple myeloma patients usually have an aggressive course and a poor prognosis. Available therapeutic options are scarce. METHODS: The objective of the current study was to evaluate responses and toxicities of VDTPACE or mCBAD with hematopoietic stem-cell support as a bridge to subsequent therapies in patients with refractory/relapsed multiple myeloma. RESULTS: Thirteen patients were included (11 mCBAD, 2 VDTPACE), and 21 cycles of chemotherapy with hematopoietic stem-cell support were delivered. Mean number of previous therapies was 4.8. Stem cells were infused on a median day 9.9 after chemotherapy. Mean time to neutrophil recovery was 18.2 days in patients receiving the first cycle and 15.9 following subsequent cycles. Before therapy, most patients were in PD (77%), PR (15%), or VGPR (8%). Following treatment, the best responses achieved were PR (46%), VGPR (46%), and CR (8%). Median overall and progression-free survivals were 17 and 9 months. There has been no case of non-relapse mortality. In the 21 cycles, the main complications were infectious. CONCLUSION: Intensive chemotherapy can decrease disease burden in patients with relapsed/refractory MM, and stem-cell support can successfully decrease toxicities and treatment-related mortality associated with these regimens and may be a good bridging option.
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Considering early-stage drug discovery programs, the Ugi four-component reaction is a valuable, flexible, and pivotal tool, facilitating the creation of two new amide bonds in a one-pot fashion to effectively yield the desired α-aminoacylamides. Here, we highlight the reputation of this reaction approach to access number and scaffold diversity of a library of isatin-based α-acetamide carboxamide oxindole hybrids, promising anticancer agents, in a mild and fast sustainable reaction process. The library was tested against six human solid tumor cell lines, among them, non-small cell lung carcinoma, cervical adenocarcinoma, breast cancer and colon adenocarcinoma. The most potent compounds 8d, 8h and 8k showed GI50 values in the range of 1-10 µM.
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BACKGROUND: Laparoscopic hiatal hernia repair (LHHR) is a complex operation requiring advanced surgical training. Surgical simulation offers a potential solution for learning complex operations without the need for high surgical volume. Our goal is to develop a virtual reality (VR) simulator for LHHR; however, data supporting task-specific metrics for this procedure are lacking. The purpose of this study was to develop and assess validity and reliability evidence of task-specific metrics for the fundoplication phase of LHHR. METHODS: In phase I, structured interviews with expert foregut surgeons were conducted to develop task-specific metrics (TSM). In phase II, participants with varying levels of surgical expertise performed a laparoscopic Nissen fundoplication procedure on a porcine stomach explant. Video recordings were independently assessed by two blinded graders using global and TSM. An intraclass correlation coefficient (ICC) was used to assess interrater reliability (IRR). Performance scores were compared using a Kruskal-Wallis test. Spearman's rank correlation was used to evaluate the association between global and TSM. RESULTS: Phase I of the study consisted of 12 interviews with expert foregut surgeons. Phase II engaged 31 surgery residents, a fellow, and 6 attendings in the simulation. Phase II results showed high IRR for both global (ICC = 0.84, p < 0.001) and TSM (ICC = 0.75, p < 0.001). Significant between-group differences were detected for both global (χ2 = 24.01, p < 0.001) and TSM (χ2 = 18.4, p < 0.001). Post hoc analysis showed significant differences in performance between the three groups for both metrics (p < 0.05). There was a strong positive correlation between the global and TSM (rs = 0.86, p < 0.001). CONCLUSION: We developed task-specific metrics for LHHR and using a fundoplication model, we documented significant reliability and validity evidence. We anticipate that these LHHR task-specific metrics will be useful in our planned VR simulator.
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Fundoplicatura , Laparoscopia , Animais , Suínos , Humanos , Fundoplicatura/métodos , Laparoscopia/métodos , Reprodutibilidade dos Testes , Competência Clínica , Estômago , Simulação por ComputadorRESUMO
Estimating animal abundance is fundamental for effective management and conservation. It is increasingly done by combining passive acoustics with knowledge about rates at which animals produce cues (cue rates). Narwhals (Monodon monoceros) are elusive marine mammals for which passive acoustic density estimation might be plausible, but for which cue rates are lacking. Clicking rates in narwhals were investigated using a dataset from sound and movement tag records collected in August 2013-2016 and 2019 in East Greenland. Clicking rates were quantified for â¼1200 one-second-long systematic random samples from 8 different whales. Generalized additive models were used to model (1) the probability of being in a clicking state versus depth and (2) the clicking rate while in a clicking state, versus time and depth. The probability of being in a clicking state increased with depth, reaching â¼1.0 at â¼500 m, while the number of clicks per second (while in a clicking state) increased with depth. The mean cue production rate, weighted by tag duration, was 1.28 clicks per second (se = 0.13, CV = 0.10). This first cue rate for narwhals may be used for cue counting density estimation, but care should be taken if applying it to other geographical areas or seasons, given sample size, geographical, and temporal limitations.
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Ecolocação , Animais , Baleias , Sinais (Psicologia) , Acústica , Som , Vocalização AnimalRESUMO
BACKGROUND: Video-based review is paramount for operative performance assessment but can be laborious when performed manually. Hierarchical Task Analysis (HTA) is a well-known method that divides any procedure into phases, steps, and tasks. HTA requires large datasets of videos with consistent definitions at each level. Our aim was to develop an AI model for automated segmentation of phases, steps, and tasks for laparoscopic cholecystectomy videos using a standardized HTA. METHODS: A total of 160 laparoscopic cholecystectomy videos were collected from a publicly available dataset known as cholec80 and from our own institution. All videos were annotated for the beginning and ending of a predefined set of phases, steps, and tasks. Deep learning models were then separately developed and trained for the three levels using a 3D Convolutional Neural Network architecture. RESULTS: Four phases, eight steps, and nineteen tasks were defined through expert consensus. The training set for our deep learning models contained 100 videos with an additional 20 videos for hyperparameter optimization and tuning. The remaining 40 videos were used for testing the performance. The overall accuracy for phases, steps, and tasks were 0.90, 0.81, and 0.65 with the average F1 score of 0.86, 0.76 and 0.48 respectively. Control of bleeding and bile spillage tasks were most variable in definition, operative management, and clinical relevance. CONCLUSION: The use of hierarchical task analysis for surgical video analysis has numerous applications in AI-based automated systems. Our results show that our tiered method of task analysis can successfully be used to train a DL model.
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Colecistectomia Laparoscópica , Aprendizado Profundo , Humanos , Redes Neurais de Computação , ColecistectomiaRESUMO
Superconducting (SC) tips for scanning tunneling microscopy (STM) can enhance a wide range of surface science studies because they offer exquisite energy resolution, allow the study of Josephson tunneling, or provide spatial contrast based on the local interaction of the SC tip with the sample. The appeal of a SC tip is also practical. An SC gap can be used to characterize and optimize the noise of a low-temperature apparatus. Unlike typical samples, SC tips can be made with less ordered materials, such as from SC polycrystalline wires or by coating a normal metal tip with a superconductor. Those recipes either require additional laboratory infrastructure or are carried out in ambient conditions, leaving an oxidized tip behind. Here, we revisit the vacuum cleaving of an Nb wire to prepare fully gapped tips in an accessible one-step procedure. To show their utility, we measure the SC gap of Nb on Au(111) to determine the base temperature of our microscope and to optimize its RF filtering. The deliberate coating of the Nb tip with Au fully suppresses the SC gap and we show how sputtering with Ar+ ions can be used to gradually recover the gap, promising tunability for tailored SC gaps sizes. ⢠Oxide free superconducting STM tips ⢠RF filter optimization.
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Passive acoustic density estimation has been gaining traction in recent years. Cue counting uses detected acoustic cues to estimate animal abundance. A cue rate, the number of acoustic cues produced per animal per unit time, is required to convert cue density into animal density. Cue rate information can be obtained from animal borne acoustic tags. For deep divers, like beaked whales, data have been analyzed considering deep dive cycles as a natural sampling unit, based on either weighted averages or generalized estimating equations. Using a sperm whale DTAG (sound-and-orientation recording tag) example we compare different approaches of estimating cue rate from acoustic tags illustrating that both approaches used before might introduce biases and suggest that the natural unit of analysis should be the whole duration of the tag itself.
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Sinais (Psicologia) , Cachalote , Animais , Acústica , SomRESUMO
Electronic nematicity has been found in a wide range of strongly correlated electron materials, resulting in the electronic states having-4.5pc]Please note that the spelling of the following author name(s) in the manuscript differs from the spelling provided in the article metadata: Izidor Benedicic. The spelling provided in the manuscript has been retained; please confirm. a symmetry that is lower than that of the crystal that hosts them. One of the most astonishing examples is [Formula: see text], in which a small in-plane component of a magnetic field induces significant resistivity anisotropy. The direction of this anisotropy follows the direction of the in-plane field. The microscopic origin of this field-induced nematicity has been a long-standing puzzle, with recent experiments suggesting a field-induced spin density wave driving the anisotropy. Here, we report spectroscopic imaging of a field-controlled anisotropy of the electronic structure at the surface of [Formula: see text]. We track the electronic structure as a function of the direction of the field, revealing a continuous change with the angle. This continuous evolution suggests a mechanism based on spin-orbit coupling resulting in compass-like control of the electronic bands. The anisotropy of the electronic structure persists to temperatures about an order of magnitude higher compared to the bulk, demonstrating novel routes to stabilize such phases over a wider temperature range.
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Introduction: Breast cancer in young women is usually considered as breast cancer occurring in women younger than 40 years and is the most frequent cancer-related cause of death in these patients. In the past few years, there seems to be an increasing trend in the prevalence of breast cancer in young women, which, associated with poorer prognosis, more aggressive histologic features, and more frequent recurrence rates, makes it a rising threat to young women. This study aimed to evaluate the biological behavior of breast cancer in young women in our institution. Material and methods: A retrospective, unicentric, cohort study was conducted between 2012 and 2016. All consecutive patients with breast cancer were enrolled in the study. Cases were divided into two groups: case group, those younger than 40 years, and control group, those 40 years or older. The exclusion criterion was nonoperative treatment. Several clinical and pathologic parameters were evaluated, as well as were overall survival time and disease-free survival time. Results: The incidence of breast cancer in young women presented a rising tendency over the study period. Significant differences were observed in the comparison of the groups according to body mass index, age at menarche, age at birth of the first child, and proliferation rate. There were no differences in overall survival and disease-free survival rates between the groups. Conclusions: Young women had a more symptomatic presentation, a greater tumor proliferation rate, but similar outcomes compared with older patients. Greater multicentric studies are needed to confirm or refute these results.
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OBJECTIVE: To analyze the karyotype test and myeloid panel with next-generation sequencing findings in patients with myelofibrosis, and to compare transplant characteristics in patients referred for bone marrow transplantation. METHODS: Retrospective, single-center study with patients diagnosed with myelofibrosis treated at Hospital Israelita Albert Einstein between 2010 and 2020. RESULTS: A total of 104 patients with myelofibrosis were examined. Patients who had not been submitted to tests in our service were excluded. The final sample comprised 69 patients. Of these 69, 56 were submitted to karyotyping and 22 to myeloid panel with next-generation sequencing. Karyotype was normal in 60% of the patients and altered in 40%. The prevalence of high-risk molecular mutations was higher in patients referred for bone marrow transplantation (100% versus 50%). The median follow-up of transplant patients was 2.4 years and the overall survival at 2 years was 80% (95%CI: 62-100%). CONCLUSION: The molecular analysis enables estimating the patient's risk and thus instituting more aggressive treatment such as bone marrow transplant for patients at higher risk, being a relevant tool to guide therapy. Given the significance of molecular analysis for therapeutic decision-making in myelofibrosis, collection and disclosure of data on the prevalence of cytogenetic changes and findings of next-generation sequencing in affected patients is important.
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Transplante de Células-Tronco Hematopoéticas , Mielofibrose Primária , Humanos , Mielofibrose Primária/genética , Mielofibrose Primária/diagnóstico , Mielofibrose Primária/terapia , Estudos Retrospectivos , Mutação , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , PrognósticoRESUMO
ABSTRACT Objective To analyze the karyotype test and myeloid panel with next-generation sequencing findings in patients with myelofibrosis, and to compare transplant characteristics in patients referred for bone marrow transplantation. Methods Retrospective, single-center study with patients diagnosed with myelofibrosis treated at Hospital Israelita Albert Einstein between 2010 and 2020. Results A total of 104 patients with myelofibrosis were examined. Patients who had not been submitted to tests in our service were excluded. The final sample comprised 69 patients. Of these 69, 56 were submitted to karyotyping and 22 to myeloid panel with next-generation sequencing. Karyotype was normal in 60% of the patients and altered in 40%. The prevalence of high-risk molecular mutations was higher in patients referred for bone marrow transplantation (100% versus 50%). The median follow-up of transplant patients was 2.4 years and the overall survival at 2 years was 80% (95%CI: 62-100%). Conclusion The molecular analysis enables estimating the patient's risk and thus instituting more aggressive treatment such as bone marrow transplant for patients at higher risk, being a relevant tool to guide therapy. Given the significance of molecular analysis for therapeutic decision-making in myelofibrosis, collection and disclosure of data on the prevalence of cytogenetic changes and findings of next-generation sequencing in affected patients is important.
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This study aimed to determine Patulin (PAT) in samples of organically and conventionally grown tomato varieties, to correlate it with their phenolic profile and at evaluating effects of phenolic extracts of tomato samples against the Penicillium expansum CCT 7549 strain. Four varieties of tomatoes (Cherry, Khaki, Italian and Long Life) subject to conventional and organic management were collected in markets in the south of Brazil. PAT was determined in samples by validated method Matrix Solid Phase Dispersion (MSPD) with detection in HPLC-PDA. Titratable acidity, phenolic profile and antifungal activity (minimum inhibitory concentration - MIC and minimum fungicidal concentration - MFC) against P. expansum were determined. In most tomatoes PAT was found at levels that were below the Maximum Recommended Level (MRL = 50 µg/kg). Samples of conventionally grown Cherry tomato showed high acidity and PAT contamination, whose correlation was confirmed by the Principal Component Analysis (PCA). Phenolic extracts of tomatoes subject to conventional management were more efficient to inhibit P. expansum, a fact that may be explained by the content of caffeic acid. However, since PAT production was not inhibited in fruit, it is recommended that PAT should be monitored and a new management strategy should be investigated.
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Patulina , Penicillium , Solanum lycopersicum , Fenóis/farmacologiaRESUMO
Molecular hybridization approaches have become an important strategy in medicinal chemistry, and to this end, we have developed a series of novel N-1,2,3-triazole-isatin hybrids that are promising as tumour anti-proliferative agents. Our isatin hybrids presented high cytotoxic activity against colon cancer cell line SW480, lung adenocarcinoma cell line A549, as well as breast cancer cell lines MCF7 and MDA-MB-231. All tested compounds demonstrated better anti-proliferation (to 1-order of magnitude) than the cis-platin (CDDP) benchmark. In order to explore potential biological targets for these compounds, we used information from previous screenings and identified as putative targets the histone acetyltransferase P-300 (EP300) and the acyl-protein thioesterase 2 (LYPLA2), both known to be involved in epigenetic regulation. Advantageous pharmacological properties were predicted for these compounds such as good total surface area of binding to aromatic and hydrophobic units in the enzyme active site. In addition, we found down-regulation of LYPLA2 and EP300 in both the MCF7 and MDA-MB-231 breast cancer cells treated with our inhibitors, but no significant effect was detected in normal breast cells MCF10A. We also observed upregulation of EP300 mRNA expression in the MCF10A cell line for some of these compounds and the same effect for LYPLA2 mRNA in MCF7 for one of our compounds. These results suggest an effect at the transcriptional regulation level and associated with oncological contexts.
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The phenomenology and radical changes seen in material properties traversing a quantum phase transition have captivated condensed matter research over the past decades. Strong electronic correlations lead to exotic electronic ground states, including magnetic order, nematicity, and unconventional superconductivity. Providing a microscopic model for these requires detailed knowledge of the electronic structure in the vicinity of the Fermi energy, promising a complete understanding of the physics of the quantum critical point. Here, we demonstrate such a measurement at the surface of Sr3Ru2O7. Our results show that, even in zero field, the electronic structure is strongly C2 symmetric and that a magnetic field drives a Lifshitz transition and induces a charge-stripe order. We track the changes of the electronic structure as a function of field via quasiparticle interference imaging at ultralow temperatures. Our results provide a complete microscopic picture of the field-induced changes of the electronic structure across the Lifshitz transition.
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Anthropogenic pressures such as the introduction of non-indigenous species (NIS) have impacted global biodiversity and ecosystems. Most marine species spreading outside their natural biogeographical limits are promoted and facilitated by maritime traffic through ballast water and hull biofouling. Propagule pressure plays a primary role in invasion success mixed with environmental conditions of the arrival port. Moreover, with the current ocean sprawl, new substrates are offered for potential NIS recruits. Here, differences in the fouling assemblages thriving inside three different ports/marinas facilities in Madeira Island were assessed for comparison. The locations showed significant differences concerning assemblage structure. Most NIS were detected in plastic floating pontoons. Funchal harbour receives most of the marine traffic in Madeira, acting as the main hub for primary NIS introductions, being recreational boating involved in NIS secondary transfers. Our results highlight the need for future management actions in island ecosystems, particularly monitoring and sampling of recreational boating.
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Incrustação Biológica , Espécies Introduzidas , Efeitos Antropogênicos , Biodiversidade , Ecossistema , NaviosRESUMO
The chromane ring system is widely distributed in nature and has proven to be a highly potent pharmacophore in medicinal chemistry, which includes the area of Alzheimer's and Parkinson's diseases. We report on the development of a gem-dimethylchroman-4-ol family that was shown to give good inhibition of equine serum butyrylcholinesterase (eqBuChE) (in the range 2.9 - 7.3 µM) and in the same range of currently used drugs. We also synthesized a small library of gem-dimethylchroman-4-amine compounds, via a simple reductive amination of the corresponding chromanone precursor, that were also selective for eqBuChE presenting inhibitions in the range 7.6 - 67 µM. Kinetic studies revealed that they were mixed inhibitors. Insights into their mechanism of action were obtained through molecular docking and STD-NMR experiments, and the most active examples showed excellent drug-likeness and pharmacological properties predicted using Swiss-ADME. We also prepared a set of propargyl gem-dimethylchromanamines, for monoamine oxidase (MAO) inhibition but they were only moderately active (the best being 28% inhibition at 1 µM on MAO-B). Overall, our compounds were found to be best suited as inhibitors for BuChE.
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Doença de Alzheimer , Doença de Alzheimer/tratamento farmacológico , Animais , Butirilcolinesterase/metabolismo , Inibidores da Colinesterase/química , Inibidores da Colinesterase/farmacologia , Cavalos , Cinética , Simulação de Acoplamento Molecular , Estrutura Molecular , Monoaminoxidase/metabolismo , Inibidores da Monoaminoxidase/química , Inibidores da Monoaminoxidase/farmacologia , Relação Estrutura-AtividadeRESUMO
Ex situ breeding programs are important conservation tools for endangered freshwater fish. However, developing husbandry techniques that decrease the likelihood of disease, antimicrobial resistance, and virulence determinants acquisition during this process is challenging. In this pilot study, we conducted a captivity experiment with Portuguese nase (Iberochondrostoma lusitanicum), a critically endangered leuciscid species, to investigate the influence of simple protective measures (i.e., material disinfection protocols and animal handling with gloves) on the dynamics of a potential pathogenic genus, Aeromonas, as well as its virulence profiles and antimicrobial resistance signatures. Our findings show that antimicrobial resistance in Aeromonas spp. collected from I. lusitanicum significantly increased during the extent of the assay (5 weeks), with all isolates collected at the end of the study classified as multidrug-resistant. Additionally, humans handling fishes without protective measures were colonized by Aeromonas spp. The use of protective measures suggested a decreasing trend in Aeromonas spp. prevalence in I. lusitanicum, while bacterial isolates displayed significantly lower virulence index values when virulence phenotypical expression was tested at 22 °C. Despite this study representing an initial trial, which needs support from further research, protective measures tested are considered a simple tool to be applied in ex situ breeding programs for aquatic animals worldwide. Furthermore, current results raise concern regarding antimicrobial resistance amplification and zoonotic transmission of Aeromonas spp. in aquatic ex situ programs.
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Chloroquine (CQ) was the most effective and widely used drug for the prophylaxis and treatment of severe and non-severe malaria. Although its prophylactic use has led to resistance to P. falciparum in all endemic countries, CQ still remains the drug of choice for the treatment of vivax malaria. Otherwise, the speed in which parasite resistance to available antimalarials rises and spreads in endemic regions points to the urgent need for the development of new antimalarials. Quinoline derivatives have been used as a tool in the search for new drugs and were investigated in the present study in an attempt to produce a HIT compound to avoid the cerebral malarial (CM). Seven compounds were synthesized, including three quinoline derivate salts. The cytotoxicity and antiplasmodial activity were assayed in vitro, highlighting compound 3 as a HIT, which also showed interaction with ferriprotoporphyrin IX similarly to CQ. Physicochemical and pharmacokinetic properties of absorption were found to be favorable when analyzed in silico. The in vivo assays, using the experimental cerebral malaria (ECM) model, showed important values of parasite growth inhibition on the 7th day-post infection (Q15 15 mg/kg: 76.9%, Q30 30 mg/kg: 90,1% and Q50 50 mg/kg: 92,9%). Compound 3 also showed significant protection against the development of CM, besides hepatic and renal parameters better than CQ. In conclusion, this quinoline derivative demonstrated promising activity for the treatment of malaria and was able to avoid the development of severe malaria in mice.