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1.
Arch Pharm (Weinheim) ; 357(2): e2300560, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38032154

RESUMO

Tuberculosis (TB) disease, caused by Mycobacterium tuberculosis (Mtb) is the leading cause of death among people with human immunodeficiency virus (HIV) infection. No dual-target drug is currently being used to simultaneously treat both infections. This work aimed to obtain new multitarget HIV-TB agents, with the goal of optimizing treatments and preventing this coinfection. These compounds incorporate the structural features of azaaurones as anti-Mtb and zidovudine (AZT) as the antiretroviral moiety. The azaaurone scaffold displayed submicromolar activities against Mtb, and AZT is a potent antiretroviral drug. Six derivatives were synthetically generated, and five were evaluated against both infective agents. Evaluations of anti-HIV activity were carried out in HIV-1-infected MT-4 cells and on endogenous HIV-1 reverse transcriptase (RT) activity. The H37Rv strain was used for anti-Mtb assessments. Most compounds displayed potent antitubercular and moderate anti-HIV activity. (E)-12 exhibited a promising multitarget profile with an MIC90 of 2.82 µM and an IC50 of 1.98 µM in HIV-1-infected T lymphocyte cells, with an 84% inhibition of RT activity. Therefore, (E)-12 could be the first promising compound from a family of multitarget agents used to treat HIV-TB coinfection. In addition, the compound could offer a prototype for the development of new strategies in scientific research to treat this global health issue.


Assuntos
Benzofuranos , Coinfecção , Infecções por HIV , HIV-1 , Mycobacterium tuberculosis , Tuberculose , Humanos , Coinfecção/tratamento farmacológico , Relação Estrutura-Atividade , Tuberculose/tratamento farmacológico , Tuberculose/microbiologia , Antituberculosos/farmacologia , Antituberculosos/química , Infecções por HIV/tratamento farmacológico , Antirretrovirais/farmacologia
2.
Sensors (Basel) ; 24(7)2024 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-38610447

RESUMO

In Portugal, more than 98% of domestic cooking oil is disposed of improperly every day. This avoids recycling/reconverting into another energy. Is also may become a potential harmful contaminant of soil and water. Driven by the utility of recycled cooking oil, and leveraging the exponential growth of ubiquitous computing approaches, we propose an IoT smart solution for domestic used cooking oil (UCO) collection bins. We call this approach SWAN, which stands for Smart Waste Accumulation Network. It is deployed and evaluated in Portugal. It consists of a countrywide network of collection bin units, available in public areas. Two metrics are considered to evaluate the system's success: (i) user engagement, and (ii) used cooking oil collection efficiency. The presented system should (i) perform under scenarios of temporary communication network failures, and (ii) be scalable to accommodate an ever-growing number of installed collection units. Thus, we choose a disruptive approach from the traditional cloud computing paradigm. It relies on edge node infrastructure to process, store, and act upon the locally collected data. The communication appears as a delay-tolerant task, i.e., an edge computing solution. We conduct a comparative analysis revealing the benefits of the edge computing enabled collection bin vs. a cloud computing solution. The studied period considers four years of collected data. An exponential increase in the amount of used cooking oil collected is identified, with the developed solution being responsible for surpassing the national collection totals of previous years. During the same period, we also improved the collection process as we were able to more accurately estimate the optimal collection and system's maintenance intervals.

3.
Chembiochem ; 24(21): e202300418, 2023 11 02.
Artigo em Inglês | MEDLINE | ID: mdl-37671979

RESUMO

Intramembrane serine proteases (rhomboid proteases) are involved in a variety of biological processes and are implicated in several diseases. Here, we report 4-oxo-ß-lactams as a novel scaffold for inhibition of rhomboids. We show that they covalently react with the active site and that the covalent bond is sufficiently stable for detection of the covalent rhomboid-lactam complex. 4-Oxo-ß-lactams may therefore find future use as both inhibitors and activity-based probes for rhomboid proteases.


Assuntos
Endopeptidases , beta-Lactamas , beta-Lactamas/farmacologia , Serina Proteases
4.
Sensors (Basel) ; 24(1)2023 Dec 27.
Artigo em Inglês | MEDLINE | ID: mdl-38203010

RESUMO

Indoor air quality (IAQ) problems in school environments are very common and have significant impacts on students' performance, development and health. Indoor air conditions depend on the adopted ventilation practices, which in Mediterranean countries are essentially based on natural ventilation controlled through manual window opening. Citizen science projects directed to school communities are effective strategies to promote awareness and knowledge acquirement on IAQ and adequate ventilation management. Our multidisciplinary research team has developed a framework-SchoolAIR-based on low-cost sensors and a scalable IoT system architecture to support the improvement of IAQ in schools. The SchoolAIR framework is based on do-it-yourself sensors that continuously monitor air temperature, relative humidity, concentrations of carbon dioxide and particulate matter in school environments. The framework was tested in the classrooms of University Fernando Pessoa, and its deployment and proof of concept took place in a high school in the north of Portugal. The results obtained reveal that CO2 concentrations frequently exceed reference values during classes, and that higher concentrations of particulate matter in the outdoor air affect IAQ. These results highlight the importance of real-time monitoring of IAQ and outdoor air pollution levels to support decision-making in ventilation management and assure adequate IAQ. The proposed approach encourages the transfer of scientific knowledge from universities to society in a dynamic and active process of social responsibility based on a citizen science approach, promoting scientific literacy of the younger generation and enhancing healthier, resilient and sustainable indoor environments.


Assuntos
Poluição do Ar em Ambientes Fechados , Poluição do Ar , Ciência do Cidadão , Humanos , Ar Condicionado , Material Particulado
5.
Molecules ; 28(8)2023 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-37110574

RESUMO

The human immunodeficiency virus (HIV) produces the pathologic basis of acquired immunodeficiency syndrome (AIDS). An increase in the viral load in the body leads to a decline in the number of T lymphocytes, compromising the patient's immune system. Some opportunistic diseases may result, such as tuberculosis (TB), which is the most common in seropositive patients. Long-term treatment is required for HIV-TB coinfection, and cocktails of drugs for both diseases are used concomitantly. The most challenging aspects of treatment are the occurrence of drug interactions, overlapping toxicity, no adherence to treatment and cases of resistance. Recent approaches have involved using molecules that can act synergistically on two or more distinct targets. The development of multitarget molecules could overcome the disadvantages of the therapies used to treat HIV-TB coinfection. This report is the first review on using molecules with activities against HIV and Mycobacterium tuberculosis (MTB) for molecular hybridization and multitarget strategies. Here, we discuss the importance and development of multiple targets as a means of improving adherence to therapy in cases of the coexistence of these pathologies. In this context, several studies on the development of structural entities to treat HIV-TB simultaneously are discussed.


Assuntos
Coinfecção , Infecções por HIV , Mycobacterium tuberculosis , Tuberculose , Humanos , HIV , Antituberculosos/farmacologia , Antituberculosos/uso terapêutico , Coinfecção/tratamento farmacológico , Coinfecção/epidemiologia , Tuberculose/complicações , Tuberculose/tratamento farmacológico , Tuberculose/microbiologia , Infecções por HIV/complicações , Infecções por HIV/tratamento farmacológico
6.
J Am Chem Soc ; 144(37): 16930-16952, 2022 09 21.
Artigo em Inglês | MEDLINE | ID: mdl-36007011

RESUMO

Leucine-rich repeat kinase 2 (LRRK2) is one of the most promising targets for Parkinson's disease. LRRK2-targeting strategies have primarily focused on type 1 kinase inhibitors, which, however, have limitations as the inhibited protein can interfere with natural mechanisms, which could lead to undesirable side effects. Herein, we report the development of LRRK2 proteolysis targeting chimeras (PROTACs), culminating in the discovery of degrader XL01126, as an alternative LRRK2-targeting strategy. Initial designs and screens of PROTACs based on ligands for E3 ligases von Hippel-Lindau (VHL), Cereblon (CRBN), and cellular inhibitor of apoptosis (cIAP) identified the best degraders containing thioether-conjugated VHL ligand VH101. A second round of medicinal chemistry exploration led to qualifying XL01126 as a fast and potent degrader of LRRK2 in multiple cell lines, with DC50 values within 15-72 nM, Dmax values ranging from 82 to 90%, and degradation half-lives spanning from 0.6 to 2.4 h. XL01126 exhibits high cell permeability and forms a positively cooperative ternary complex with VHL and LRRK2 (α = 5.7), which compensates for a substantial loss of binary binding affinities to VHL and LRRK2, underscoring its strong degradation performance in cells. Remarkably, XL01126 is orally bioavailable (F = 15%) and can penetrate the blood-brain barrier after either oral or parenteral dosing in mice. Taken together, these experiments qualify XL01126 as a suitable degrader probe to study the noncatalytic and scaffolding functions of LRRK2 in vitro and in vivo and offer an attractive starting point for future drug development.


Assuntos
Barreira Hematoencefálica , Ubiquitina-Proteína Ligases , Animais , Camundongos , Barreira Hematoencefálica/metabolismo , Leucina , Ligantes , Inibidores de Proteínas Quinases/farmacologia , Proteólise , Sulfetos , Ubiquitina-Proteína Ligases/metabolismo
7.
Molecules ; 27(15)2022 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-35897894

RESUMO

Necroptosis has emerged as an exciting target in oncological, inflammatory, neurodegenerative, and autoimmune diseases, in addition to acute ischemic injuries. It is known to play a role in innate immune response, as well as in antiviral cellular response. Here we devised a concerted in silico and experimental framework to identify novel RIPK1 inhibitors, a key necroptosis factor. We propose the first in silico model for the prediction of new RIPK1 inhibitor scaffolds by combining docking and machine learning methodologies. Through the data analysis of patterns in docking results, we derived two rules, where rule #1 consisted of a four-residue signature filter, and rule #2 consisted of a six-residue similarity filter based on docking calculations. These were used in consensus with a machine learning QSAR model from data collated from ChEMBL, the literature, in patents, and from PubChem data. The models allowed for good prediction of actives of >90, 92, and 96.4% precision, respectively. As a proof-of-concept, we selected 50 compounds from the ChemBridge database, using a consensus of both molecular docking and machine learning methods, and tested them in a phenotypic necroptosis assay and a biochemical RIPK1 inhibition assay. A total of 7 of the 47 tested compounds demonstrated around 20−25% inhibition of RIPK1's kinase activity but, more importantly, these compounds were discovered to occupy new areas of chemical space. Although no strong actives were found, they could be candidates for further optimization, particularly because they have new scaffolds. In conclusion, this screening method may prove valuable for future screening efforts as it allows for the exploration of new areas of the chemical space in a very fast and inexpensive manner, therefore providing efficient starting points amenable to further hit-optimization campaigns.


Assuntos
Necroptose , Simulação por Computador , Ligantes , Simulação de Acoplamento Molecular
8.
Angew Chem Int Ed Engl ; 61(47): e202210498, 2022 11 21.
Artigo em Inglês | MEDLINE | ID: mdl-36089535

RESUMO

Dipeptidyl peptidases 8 and 9 (DPP8/9) have gathered interest as drug targets due to their important roles in biological processes like immunity and tumorigenesis. Elucidation of their distinct individual functions remains an ongoing task and could benefit from the availability of novel, chemically diverse and selective chemical tools. Here, we report the activity-based protein profiling (ABPP)-mediated discovery of 4-oxo-ß-lactams as potent, non-substrate-like nanomolar DPP8/9 inhibitors. X-ray crystallographic structures revealed different ligand binding modes for DPP8 and DPP9, including an unprecedented targeting of an extended S2' (eS2') subsite in DPP8. Biological assays confirmed inhibition at both target and cellular levels. Altogether, our integrated chemical proteomics and structure-guided small molecule design approach led to novel DPP8/9 inhibitors with alternative molecular inhibition mechanisms, delivering the highest selectivity index reported to date.


Assuntos
Dipeptidases , Dipeptidases/metabolismo , beta-Lactamas/farmacologia , Dipeptidil Peptidases e Tripeptidil Peptidases , Proteômica , Cristalografia por Raios X
9.
Antimicrob Agents Chemother ; 65(7): e0151320, 2021 06 17.
Artigo em Inglês | MEDLINE | ID: mdl-33903112

RESUMO

Leishmaniasis is one of the most challenging neglected tropical diseases and remains a global threat to public health. Currently available therapies for leishmaniases present significant drawbacks and are rendered increasingly inefficient due to parasite resistance, making the need for more effective, safer, and less expensive drugs an urgent one. In our efforts to identify novel chemical scaffolds for the development of antileishmanial agents, we have screened in-house antiplasmodial libraries against axenic and intracellular forms of Leishmania infantum, Leishmania amazonensis, and Leishmania major. Several of the screened compounds showed half-maximal inhibitory concentrations (IC50s) against intracellular L. infantum parasites in the submicromolar range (compounds 1h, IC50 = 0.9 µM, and 1n, IC50 = 0.7 µM) and selectivity indexes of 11 and 9.7, respectively. Compounds also displayed activity against L. amazonensis and L. major parasites, albeit in the low micromolar range. Mechanistic studies revealed that compound 1n efficiently inhibits oxygen consumption and significantly decreases the mitochondrial membrane potential in L. infantum axenic amastigotes, suggesting that this chemotype acts, at least in part, by interfering with mitochondrial function. Structure-activity analysis suggests that compound 1n is a promising antileishmanial lead and emphasizes the potential of the quinoline-(1H)-imine chemotype for the future development of new antileishmanial agents.


Assuntos
Antiprotozoários , Leishmania mexicana , Leishmaniose , Animais , Antiprotozoários/farmacologia , Antiprotozoários/uso terapêutico , Iminas/uso terapêutico , Leishmaniose/tratamento farmacológico , Macrófagos , Camundongos , Camundongos Endogâmicos BALB C
10.
J Org Chem ; 86(20): 14192-14198, 2021 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-34235919

RESUMO

We combine random sampling and active machine learning (ML) to optimize the synthesis of isomacroin, executing only 3% of all possible Friedländer reactions. Employing kinetic modeling, we augment machine intuition by extracting mechanistic knowledge and verify that a global optimum was obtained with ML. Our study contributes evidence on the potential of multiscale approaches to expedite the access to chemical matter, further democratizing organic chemistry in a data-motivated fashion.


Assuntos
Química Orgânica , Aprendizado de Máquina , Cinética
11.
Int J Mol Sci ; 22(10)2021 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-34069782

RESUMO

Parkinson's disease (PD) is the second most common neurodegenerative disorder, mainly characterized by motor deficits correlated with progressive dopaminergic neuronal loss in the substantia nigra pars compacta (SN). Necroptosis is a caspase-independent form of regulated cell death mediated by the concerted action of receptor-interacting protein 3 (RIP3) and the pseudokinase mixed lineage domain-like protein (MLKL). It is also usually dependent on RIP1 kinase activity, influenced by further cellular clues. Importantly, necroptosis appears to be strongly linked to several neurodegenerative diseases, including PD. Here, we aimed at identifying novel chemical inhibitors of necroptosis in a PD-mimicking model, by conducting a two-step screening. Firstly, we phenotypically screened a library of 31 small molecules using a cellular model of necroptosis and, thereafter, the hit compound effect was validated in vivo in a sub-acute 1-methyl-1-4-phenyl-1,2,3,6-tetrahydropyridine hydrochloride (MPTP) PD-related mouse model. From the initial compounds, we identified one hit-Oxa12-that strongly inhibited necroptosis induced by the pan-caspase inhibitor zVAD-fmk in the BV2 murine microglia cell line. More importantly, mice exposed to MPTP and further treated with Oxa12 showed protection against MPTP-induced dopaminergic neuronal loss in the SN and striatum. In conclusion, we identified Oxa12 as a hit compound that represents a new chemotype to tackle necroptosis. Oxa12 displays in vivo effects, making this compound a drug candidate for further optimization to attenuate PD pathogenesis.


Assuntos
Neurônios Dopaminérgicos/metabolismo , Necroptose/efeitos dos fármacos , Animais , Apoptose/efeitos dos fármacos , Encéfalo/metabolismo , Morte Celular/efeitos dos fármacos , Corpo Estriado/metabolismo , Modelos Animais de Doenças , Dopamina/metabolismo , Neurônios Dopaminérgicos/efeitos dos fármacos , Proteínas Ativadoras de GTPase/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Microglia/metabolismo , Necroptose/fisiologia , Doenças Neurodegenerativas/metabolismo , Doença de Parkinson/metabolismo , Parte Compacta da Substância Negra/metabolismo , Proteína Serina-Treonina Quinases de Interação com Receptores/metabolismo , Substância Negra/metabolismo
12.
Inorg Chem ; 59(17): 12722-12732, 2020 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-32838513

RESUMO

A small library of "half-sandwich" cyclopentadienylruthenium(II) compounds of the general formula [(η5-C5R5)Ru(PPh3)(N-N)][PF6], a scaffold hitherto absent from the toolbox of antiplasmodials, was screened for activity against the blood stage of CQ-sensitive 3D7-GFP, CQ-resistant Dd2, and artemisinin-resistant IPC5202 Plasmodium falciparum strains and the liver stage of Plasmodium berghei. The best-performing compounds displayed dual-stage activity, with single-digit nanomolar IC50 values against blood-stage malaria parasites, nanomolar activity against liver-stage parasites, and residual cytotoxicity against HepG2 and Huh7 mammalian cells. The parasitic absorption/distribution of 7-nitrobenzoxadiazole-appended fluorescent compounds Ru4 and Ru5 was investigated by confocal fluorescence microscopy, revealing parasite-selective absorption in infected erythrocytes and nuclear accumulation of both compounds. The lead compound Ru2 impaired asexual parasite differentiation, exhibiting fast parasiticidal activity against both ring and trophozoite stages of a synchronized culture of the P. falciparum 3D7 strain. These results point to cyclopentadienylruthenium(II) complexes as a highly promising chemotype for the development of dual-stage antiplasmodials.


Assuntos
Antimaláricos/química , Antimaláricos/farmacologia , Complexos de Coordenação/química , Complexos de Coordenação/farmacologia , Ciclopentanos/química , Rutênio/química , Resistência a Medicamentos/efeitos dos fármacos , Eritrócitos/efeitos dos fármacos , Células Hep G2 , Humanos , Oxidiazóis/química , Plasmodium berghei/efeitos dos fármacos , Plasmodium falciparum/efeitos dos fármacos
13.
Int J Mol Sci ; 21(22)2020 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-33238468

RESUMO

Despite being discovered and isolated more than one hundred years ago, tuberculosis (TB) remains a global public health concern arch. Our inability to eradicate this bacillus is strongly related with the growing resistance, low compliance to current drugs, and the capacity of the bacteria to coexist in a state of asymptomatic latency. This last state can be sustained for years or even decades, waiting for a breach in the immune system to become active again. Furthermore, most current therapies are not efficacious against this state, failing to completely clear the infection. Over the years, a series of experimental methods have been developed to mimic the latent state, currently used in drug discovery, both in vitro and in vivo. Most of these methods focus in one specific latency inducing factor, with only a few taking into consideration the complexity of the granuloma and the genomic and proteomic consequences of each physiological factor. A series of targets specifically involved in latency have been studied over the years with promising scaffolds being discovered and explored. Taking in account that solving the latency problem is one of the keys to eradicate the disease, herein we compile current therapies and diagnosis techniques, methods to mimic latency and new targets and compounds in the pipeline of drug discovery.


Assuntos
Proteínas de Bactérias/genética , Tuberculose Latente/tratamento farmacológico , Mycobacterium tuberculosis/genética , Proteômica , Proteínas de Bactérias/antagonistas & inibidores , Descoberta de Drogas , Humanos , Sistema Imunitário/efeitos dos fármacos , Tuberculose Latente/genética , Tuberculose Latente/microbiologia , Terapia de Alvo Molecular , Mycobacterium tuberculosis/efeitos dos fármacos , Mycobacterium tuberculosis/patogenicidade
14.
Adv Exp Med Biol ; 1170: 37-68, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-32067202

RESUMO

Locomotion is an important human faculty that affects an individual's life, bringing not only physical and psychosocial implications but also heavy social-economic consequences. Thus, it becomes paramount to find means (augmentative/assistive devices) to empower the user's residual capacities and promote functional recovery.In this context, a smart walker (SW) is explored for further clinical evaluation of ataxic patients during walker-assisted and to serve as a functional compensation and assist-as-needed personalized/customized rehabilitation tool, autonomously adapting assistance to the users' needs, through innovative combination of real-time multimodal sensory information from SW built-in sensors. To meet the users' needs, its design was weighed, considering to whom it is intended.Thereby, this paper presents the system overview, focusing on design considerations, mechanical structure (frame and main components), electronic and mechatronic components, followed by its functionalities. Lastly, it presents results regarding the main functionalities, addressing clinical evidence.


Assuntos
Ataxia/reabilitação , Robótica/instrumentação , Andadores , Humanos , Tecnologia Assistiva
15.
Int J Mol Sci ; 20(22)2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31731801

RESUMO

Protozoan diseases continue to be a worldwide social and economic health problem. Increased drug resistance, emerging cross resistance, and lack of new drugs with novel mechanisms of action significantly reduce the effectiveness of current antiprotozoal therapies. While drug resistance associated to anti-infective agents is a reality, society seems to remain unaware of its proportions and consequences. Parasites usually develops ingenious and innovative mechanisms to achieve drug resistance, which requires more research and investment to fight it. In this review, drug resistance developed by protozoan parasites Plasmodium, Leishmania, and Trypanosoma will be discussed.


Assuntos
Antiprotozoários/uso terapêutico , Plasmodium/patogenicidade , Infecções por Protozoários/tratamento farmacológico , Animais , Humanos , Leishmania/efeitos dos fármacos , Leishmania/patogenicidade , Malária/tratamento farmacológico , Malária/fisiopatologia , Plasmodium/efeitos dos fármacos , Infecções por Protozoários/parasitologia
16.
J Med Syst ; 42(11): 232, 2018 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-30317396

RESUMO

Freezing of Gait (FOG) is one of the most disabling gait disorders in Parkinson's Disease (PD), for which the efficacy of the medication is reduced, highlighting the use of non-pharmacological solutions. In particular, patients present less difficulties in overcoming FOG when using feedback and especially with Biofeedback Systems. In this study it is intended to detect the frequency threshold and the minimum interval of perception of the vibrotactile feedback, through a proposed wearable system, a waistband. Experimental tests were carried out that considered a temporal, spatial and spatiotemporal context, for which 15 healthy and 15 PD patients participated. It was detected as threshold frequency 180 Hz and for minimum interval of vibration perception 250 ms. The identification of this threshold frequency and this interval will allow us to select the frequency and the minimum interval of vibration to be used in a Vibrotactile Biofeedback Device for patients with PD, in order to help them to overcome FOG.


Assuntos
Transtornos Neurológicos da Marcha/fisiopatologia , Neurorretroalimentação/instrumentação , Doença de Parkinson/fisiopatologia , Tecnologia de Sensoriamento Remoto/instrumentação , Vibração , Abdome , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Análise Espaço-Temporal
17.
Sensors (Basel) ; 17(11)2017 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-29137136

RESUMO

Shape memory polyurethanes (SMPUs) are thermally activated shape memory materials, which can be used as actuators or sensors in applications including aerospace, aeronautics, automobiles or the biomedical industry. The accurate characterization of the memory effect of these materials is therefore mandatory for the technology's success. The shape memory characterization is normally accomplished using mechanical testing coupled with a heat source, where a detailed knowledge of the heat cycle and its influence on the material properties is paramount but difficult to monitor. In this work, fiber Bragg grating (FBG) sensors were embedded into SMPU samples aiming to study and characterize its shape memory effect. The samples were obtained by injection molding, and the entire processing cycle was successfully monitored, providing a process global quality signature. Moreover, the integrity and functionality of the FBG sensors were maintained during and after the embedding process, demonstrating the feasibility of the technology chosen for the purpose envisaged. The results of the shape memory effect characterization demonstrate a good correlation between the reflected FBG peak with the temperature and induced strain, proving that this technology is suitable for this particular application.

18.
Bioorg Med Chem ; 24(8): 1786-92, 2016 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-26968650

RESUMO

A structure-activity relationship study was performed with ten 8-aminoquinoline-squaramides compounds active against liver stage malaria parasites, using human hepatoma cells (Huh7) infected by Plasmodium berghei parasites. In addition, their blood-schizontocidal activity was assessed against chloroquine-resistant W2 strain Plasmodium falciparum. Compound 3 was 7.3-fold more potent than the positive control primaquine against liver-stage parasites, illustrating the importance of the squarate moiety to activity.


Assuntos
Antiprotozoários/farmacologia , Fígado/parasitologia , Malária/parasitologia , Plasmodium falciparum/efeitos dos fármacos , Quinina/análogos & derivados , Antiprotozoários/síntese química , Antiprotozoários/química , Linhagem Celular Tumoral , Relação Dose-Resposta a Droga , Células HEK293 , Humanos , Malária/tratamento farmacológico , Estrutura Molecular , Testes de Sensibilidade Parasitária , Quinina/síntese química , Quinina/química , Quinina/farmacologia , Relação Estrutura-Atividade
19.
Proc Natl Acad Sci U S A ; 110(30): E2838-47, 2013 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-23836641

RESUMO

Residence within a customized vacuole is a highly successful strategy used by diverse intracellular microorganisms. The parasitophorous vacuole membrane (PVM) is the critical interface between Plasmodium parasites and their possibly hostile, yet ultimately sustaining, host cell environment. We show that torins, developed as ATP-competitive mammalian target of rapamycin (mTOR) kinase inhibitors, are fast-acting antiplasmodial compounds that unexpectedly target the parasite directly, blocking the dynamic trafficking of the Plasmodium proteins exported protein 1 (EXP1) and upregulated in sporozoites 4 (UIS4) to the liver stage PVM and leading to efficient parasite elimination by the hepatocyte. Torin2 has single-digit, or lower, nanomolar potency in both liver and blood stages of infection in vitro and is likewise effective against both stages in vivo, with a single oral dose sufficient to clear liver stage infection. Parasite elimination and perturbed trafficking of liver stage PVM-resident proteins are both specific aspects of torin-mediated Plasmodium liver stage inhibition, indicating that torins have a distinct mode of action compared with currently used antimalarials.


Assuntos
Antimaláricos/farmacologia , Fígado/parasitologia , Proteínas de Membrana/metabolismo , Naftiridinas/farmacologia , Plasmodium/efeitos dos fármacos , Animais , Plasmodium/metabolismo , Vacúolos/metabolismo
20.
J Lipid Res ; 56(11): 2158-71, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26351365

RESUMO

Cytotoxic bile acids, such as deoxycholic acid (DCA), are responsible for hepatocyte cell death during intrahepatic cholestasis. The mechanisms responsible for this effect are unclear, and recent studies conflict, pointing to either a modulation of plasma membrane structure or mitochondrial-mediated toxicity through perturbation of mitochondrial outer membrane (MOM) properties. We conducted a comprehensive comparative study of the impact of cytotoxic and cytoprotective bile acids on the membrane structure of different cellular compartments. We show that DCA increases the plasma membrane fluidity of hepatocytes to a minor extent, and that this effect is not correlated with the incidence of apoptosis. Additionally, plasma membrane fluidity recovers to normal values over time suggesting the presence of cellular compensatory mechanisms for this perturbation. Colocalization experiments in living cells confirmed the presence of bile acids within mitochondrial membranes. Experiments with active isolated mitochondria revealed that physiologically active concentrations of DCA change MOM order in a concentration- and time-dependent manner, and that these changes preceded the mitochondrial permeability transition. Importantly, these effects are not observed on liposomes mimicking MOM lipid composition, suggesting that DCA apoptotic activity depends on features of mitochondrial membranes that are absent in protein-free mimetic liposomes, such as the double-membrane structure, lipid asymmetry, or mitochondrial protein environment. In contrast, the mechanism of action of cytoprotective bile acids is likely not associated with changes in cellular membrane structure.


Assuntos
Apoptose , Ácido Desoxicólico/farmacologia , Membranas Mitocondriais/metabolismo , Animais , Sobrevivência Celular , Células Cultivadas , Hepatócitos/efeitos dos fármacos , Hepatócitos/metabolismo , Masculino , Fluidez de Membrana , Mitocôndrias Hepáticas/efeitos dos fármacos , Mitocôndrias Hepáticas/metabolismo , Permeabilidade , Ratos , Transdução de Sinais
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