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1.
J Agric Food Chem ; 72(18): 10247-10256, 2024 May 08.
Artículo en Inglés | MEDLINE | ID: mdl-38683760

RESUMEN

Some forage legumes synthesize phytoestrogens. We conducted a glasshouse study to investigate how water stress (drought and waterlogging) influences phytoestrogen accumulation in red clover and kura clover. Compared to the red clover control, the 20 day drought resulted in an over 100% increase in the phytoestrogens formononetin and biochanin A, which together accounted for 91-96% of the total phytoestrogens measured. Waterlogging resulted in elevated concentrations of daidzein, genistein, and prunetin but not formononetin or biochanin A. Concentrations of phytoestrogens in kura clover were low or undetectable, regardless of water stress treatment. Leaf water potential was the most explanatory single-predictor of the variation in concentrations of formononetin, biochanin A, and total phytoestrogens in red clover. These results suggest that drought-stressed red clover may have higher potential to lead to estrogenic effects in ruminant livestock and that kura clover is a promising alternative low- or no-phytoestrogen perennial forage legume.


Asunto(s)
Fitoestrógenos , Trifolium , Trifolium/metabolismo , Trifolium/química , Trifolium/crecimiento & desarrollo , Fitoestrógenos/metabolismo , Fitoestrógenos/análisis , Agua/metabolismo , Agua/análisis , Isoflavonas/metabolismo , Isoflavonas/análisis , Sequías , Genisteína/análisis , Genisteína/metabolismo
2.
Phytomedicine ; 128: 155414, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38503155

RESUMEN

BACKGROUND: Chagas disease and leishmaniasis affect a significant portion of the Latin American population and still lack efficient treatments. In this context, natural products emerge as promising compounds for developing more effective therapies, aiming to mitigate side effects and drug resistance. Notably, species from the Amaryllidaceae family emerge as potential reservoirs of antiparasitic agents due to the presence of diverse biologically active alkaloids. PURPOSE: To assess the anti-Trypanosoma cruzi and anti-Leishmania infantum activity of five isolated alkaloids from Hippeastrum aulicum Herb. (Amaryllidaceae) against different life stages of the parasites using in silico and in vitro assays. Furthermore, molecular docking was employed to evaluate the interaction of the most active alkaloids. METHODS: Five natural isoquinoline alkaloids isolated in suitable quantities for in vitro testing underwent preliminary in silico analysis to predict their potential efficacy against Trypanosoma cruzi (amastigote and trypomastigote forms) and Leishmania infantum (amastigote and promastigote forms). The in vitro antiparasitic activity and mammalian cytotoxicity were investigated with a subsequent comparison of both analysis (in silico and in vitro) findings. Additionally, this study employed the molecular docking technique, utilizing cruzain (T. cruzi) and sterol 14α-demethylase (CYP51, L. infantum) as crucial biological targets for parasite survival, specifically focusing on compounds that exhibited promising activities against both parasites. RESULTS: Through computational techniques, it was identified that the alkaloids haemanthamine (1) and lycorine (8) were the most active against T. cruzi (amastigote and trypomastigote) and L. infantum (amastigote and promastigote), while also revealing unprecedented activity of alkaloid 7­methoxy-O-methyllycorenine (6). The in vitro analysis confirmed the in silico tests, in which compound 1 presented the best activities against the promastigote and amastigote forms of L. infantum with half-maximal inhibitory concentration (IC50) 0.6 µM and 1.78 µM, respectively. Compound 8 exhibited significant activity against the amastigote form of T. cruzi (IC50 7.70 µM), and compound 6 demonstrated activity against the trypomastigote forms of T. cruzi and amastigote of L. infantum, with IC50 values of 89.55 and 86.12 µM, respectively. Molecular docking analyses indicated that alkaloids 1 and 8 exhibited superior interaction energies compared to the inhibitors. CONCLUSION: The hitherto unreported potential of compound 6 against T. cruzi trypomastigotes and L. infantum amastigotes is now brought to the forefront. Furthermore, the acquired dataset signifies that the isolated alkaloids 1 and 8 from H. aulicum might serve as prototypes for subsequent structural refinements aimed at the exploration of novel leads against both T. cruzi and L. infantum parasites.


Asunto(s)
Alcaloides , Amaryllidaceae , Isoquinolinas , Leishmania infantum , Simulación del Acoplamiento Molecular , Trypanosoma cruzi , Trypanosoma cruzi/efectos de los fármacos , Leishmania infantum/efectos de los fármacos , Amaryllidaceae/química , Alcaloides/farmacología , Alcaloides/química , Alcaloides/aislamiento & purificación , Isoquinolinas/farmacología , Isoquinolinas/química , Isoquinolinas/aislamiento & purificación , Animales , Extractos Vegetales/farmacología , Extractos Vegetales/química , Humanos , Antiparasitarios/farmacología , Antiparasitarios/química , Antiparasitarios/aislamiento & purificación , Antiprotozoarios/farmacología , Antiprotozoarios/química , Antiprotozoarios/aislamiento & purificación
5.
Phytomedicine, v. 128, 155414, jun. 2024
Artículo en Inglés | Sec. Est. Saúde SP, SESSP-IBPROD, Sec. Est. Saúde SP | ID: bud-5286

RESUMEN

Background Chagas disease and leishmaniasis affect a significant portion of the Latin American population and still lack efficient treatments. In this context, natural products emerge as promising compounds for developing more effective therapies, aiming to mitigate side effects and drug resistance. Notably, species from the Amaryllidaceae family emerge as potential reservoirs of antiparasitic agents due to the presence of diverse biologically active alkaloids. Purpose To assess the anti-Trypanosoma cruzi and anti-Leishmania infantum activity of five isolated alkaloids from Hippeastrum aulicum Herb. (Amaryllidaceae) against different life stages of the parasites using in silico and in vitro assays. Furthermore, molecular docking was employed to evaluate the interaction of the most active alkaloids. Methods Five natural isoquinoline alkaloids isolated in suitable quantities for in vitro testing underwent preliminary in silico analysis to predict their potential efficacy against Trypanosoma cruzi (amastigote and trypomastigote forms) and Leishmania infantum (amastigote and promastigote forms). The in vitro antiparasitic activity and mammalian cytotoxicity were investigated with a subsequent comparison of both analysis (in silico and in vitro) findings. Additionally, this study employed the molecular docking technique, utilizing cruzain (T. cruzi) and sterol 14α-demethylase (CYP51, L. infantum) as crucial biological targets for parasite survival, specifically focusing on compounds that exhibited promising activities against both parasites. Results Through computational techniques, it was identified that the alkaloids haemanthamine (1) and lycorine (8) were the most active against T. cruzi (amastigote and trypomastigote) and L. infantum (amastigote and promastigote), while also revealing unprecedented activity of alkaloid 7‑methoxy-O-methyllycorenine (6). The in vitro analysis confirmed the in silico tests, in which compound 1 presented the best activities against the promastigote and amastigote forms of L. infantum with half-maximal inhibitory concentration (IC50) 0.6 µM and 1.78 µM, respectively. Compound 8 exhibited significant activity against the amastigote form of T. cruzi (IC50 7.70 µM), and compound 6 demonstrated activity against the trypomastigote forms of T. cruzi and amastigote of L. infantum, with IC50 values of 89.55 and 86.12 µM, respectively. Molecular docking analyses indicated that alkaloids 1 and 8 exhibited superior interaction energies compared to the inhibitors. Conclusion The hitherto unreported potential of compound 6 against T. cruzi trypomastigotes and L. infantum amastigotes is now brought to the forefront. Furthermore, the acquired dataset signifies that the isolated alkaloids 1 and 8 from H. aulicum might serve as prototypes for subsequent structural refinements aimed at the exploration of novel leads against both T. cruzi and L. infantum parasites.

6.
J Comp Eff Res ; 12(12): e230023, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37916706

RESUMEN

Aim: This study was designed to recommend strategies to improve prostate patients' access to radiotherapy treatment in the Brazilian Unified Health System, along with a cost-tool to support radiotherapy care pathways' lead times and costs. Methods: Data was collected prospectively from patients with prostate cancer receiving radiotherapy in two Brazilian centers to provide data to apply design thinking and process reengineering techniques. The current status of the radiotherapy pathway was determined and the length of time taken for in-hospital activities was measured using data exported from ARIA®. Interviews with patients were used to estimate their waiting periods. This provided the data used to provide recommended strategies and the cost tool based on time-driven activity-based costing. The strategies were classified according to priority. Results: Data from 47 patients were analyzed. The mean interval from diagnosis to start of radiotherapy was 349 days (SD581), and the mean interval from seeking medical attention to starting treatment was 635 days (SD629). Twelve strategies affecting in-hospital processes and 11 impacting patients' care pathways and experiences are recommended, mostly focused on system improvement opportunities. A time-driven activity-based costing monitoring using data extracted from ARIA was coded and can be used by centers as a cost assessment guide. Conclusion: This study uses reengineering and design techniques to introduce priority strategies to allow more efficient and patient-centered radiotherapy.


Asunto(s)
Neoplasias de la Próstata , Atención de Salud Universal , Masculino , Humanos , Neoplasias de la Próstata/radioterapia , Atención a la Salud , Brasil
7.
mBio ; : e0180323, 2023 Nov 06.
Artículo en Inglés | MEDLINE | ID: mdl-37929970

RESUMEN

Visceral leishmaniasis (VL) is a parasitic disease endemic across multiple regions of the world and is fatal if untreated. New therapeutic options with diverse mechanisms of actions (MoAs) are required to consolidate progress toward control of this disease and combat drug resistance. Here, we describe the development of a scalable resistance library screen (RES-Seq) as a tool to facilitate the identification and prioritization of anti-leishmanial compounds acting via novel MoA. We have amassed a large collection of Leishmania donovani cell lines resistant to frontline drugs and compounds in the VL pipeline, with resistance-conferring mutations fully characterized. New phenotypic hits screened against this highly curated panel of resistant lines can determine cross-resistance and potentially shared MoA. The ability to efficiently identify compounds acting via previously established MoA is vital to maintain diversity within drug development portfolios. To expedite screening, short identifier DNA barcodes were introduced into resistant clones enabling pooling and simultaneous screening of multiple cell lines. Illumina sequencing of barcodes enables the growth kinetics and relative fitness of multiple cell lines under compound selection to be tracked. Optimal conditions allowing discrimination of resistant and sensitive clones were established (3× and 10× EC50 for 3 days) and applied to screening of a complex library with VL preclinical and clinical drug candidates. RES-Seq is set to play an important role in ensuring that anti-leishmanial compounds exploiting diverse mechanisms of action are developed, ultimately providing options for future drug combination strategies.IMPORTANCEVisceral leishmaniasis (VL) remains the third largest parasitic killer worldwide, responsible for 20,000-30,000 deaths each year. Control and ultimate elimination of VL will require a range of therapeutic options with diverse mechanisms of action to combat drug resistance. One approach to ensure that compounds in development exploit diverse mechanisms of action is to screen them against highly curated cell lines resistant to drugs already in the VL pipeline. The identification of cross-resistant cell lines indicates that test compounds are likely acting via previously established mechanisms. Current cross-resistance screens are limited by the requirement to profile individual resistant cell lines one at a time. Here, we introduce unique DNA barcodes into multiple resistant cell lines to facilitate parallel profiling. Utilizing the power of Illumina sequencing, growth kinetics and relative fitness under compound selection can be monitored revolutionizing our ability to identify and prioritize compounds acting via novel mechanisms.

8.
Mol Biochem Parasitol ; 256: 111590, 2023 12.
Artículo en Inglés | MEDLINE | ID: mdl-37652239

RESUMEN

Previous work has shown that the TbFUT1 and LmjFUT1 genes encode essential fucosyltransferases located inside the single mitochondria of the protozoan parasites Trypanosoma brucei and Leishmania major, respectively. However, nothing was known about the orthologous gene TcFUT1 or its gene product in Trypanosoma cruzi, aetiological agent of Chagas disease. In this study, we describe the overexpression of TcFUT1 with a C-terminal 6xMyc epitope tag in T. cruzi epimastigote cells. Overexpressed and immunoprecipitated TcFUT1-6xMyc was used to demonstrate enzymatic activity and to explore substrate specificity. This defined TcFUT1 as a GDP-Fuc : ßGal α1-2 fucosyltransferase with a strict requirement for acceptor glycans with non-reducing terminal Galß1-3GlcNAc structures. This differs from the specificity of the T. brucei orthologue TbFUT1, which can also tolerate non-reducing terminal Galß1-4GlcNAc and Galß1-4Glc acceptor sites. Immunofluorescence microscopy using α-Myc tag antibodies also showed a mitochondrial location for TcFUT1 in T. cruzi epimastigote cells. Collectively, these results are like those described for TbFUT1 and LmjFUT1 from T. brucei and L. major, suggesting that FUT1 gene products have conserved function for across the trypanosomatids and may share therapeutic target potential.


Asunto(s)
Enfermedad de Chagas , Leishmania major , Trypanosoma cruzi , Humanos , Trypanosoma cruzi/genética , Fucosiltransferasas/genética , Leishmania major/genética , Mitocondrias
9.
Viana do Castelo; s.n; 20230720.
Tesis en Portugués | BDENF - Enfermería | ID: biblio-1512057

RESUMEN

O presente trabalho surge no âmbito da Unidade Curricular: Estágio de Natureza Profissional com Relatório Final, inserido no plano curricular do II Curso de Mestrado em Enfermagem Comunitária, da Escola Superior de Saúde, do Instituto Politécnico de Viana do Castelo. Este tem como principal finalidade a análise critico-reflexiva da investigação e das atividades realizadas durante o estágio estruturantes do desenvolvimento simultaneamente de competências conducentes à obtenção ao grau de mestre em Enfermagem Comunitária e das competências comuns e especificas à obtenção posteriormente, do título profissional de Enfermeiro Especialista em Enfermagem Comunitária (EEEC), na área da Enfermagem de Saúde Comunitária e de Saúde Pública, atribuído pela Ordem dos Enfermeiros (OE). Decorreu no período de 1 de março a 31 de agosto de 2022. O desenvolvimento deste percurso, teve como problemática central a vigilância epidemiológica dos diagnósticos de enfermagem (VEDE), a partir de uma Unidade de Saúde Pública (USP), tendo como alvo o processo de cuidados prestados pelos enfermeiros do Agrupamento de Centros de Saúde (ACeS) da região norte. Para a compreensão desta realidade e do potencial de intervenção que lhe está inerente recorreu-se ao Modelo de Avaliação, Intervenção e Empoderamento Comunitário (MAIEC, Pedro Melo, 2016). Assim, tendo como objetivo principal conhecer a realidade da VEDE no ACeS, onde se realizou o estágio, realizou-se um estudo observacional, transversal e descritivo, num universo de 262 enfermeiros, sendo a amostra constituída por 77 enfermeiros. A partir da análise documental do Diagnóstico Local de Saúde e do Plano Local de Saúde do ACeS, foram identificados os principais fenómenos de enfermagem e determinadas as taxas de documentação dos mesmos por parte dos enfermeiros. Os resultados obtidos evidenciam um nível baixo de documentação dos diagnósticos de enfermagem e avaliação diagnóstica da gestão comunitária do ACeS sobre a VEDE está comprometida em todas as suas dimensões diagnósticas (liderança comunitária, participação comunitária e processo comunitário).


The present work comes within the scope of the Curricular Unit: Internship of a Professional Nature with Final Report, inserted in the curricular plan of the II Master's Course in Community Nursing, of the Superior School of Health, of the Polytechnic Institute of Viana do Castelo. This has as its main purpose the critical-reflexive analysis of the investigation and activities carried out during the structuring stage of the simultaneous development of skills leading to obtaining a master's degree in Community Nursing and common and specific skills to subsequently obtain the professional title of Nurse Specialist in Community Nursing (EEEC), in the area of Community Health Nursing and Public Health, awarded by the Order of Nurses (OE). It took place from March 1 to August 31, 2022. The development of this course had as its central problem the epidemiological surveillance of nursing diagnoses (VEDE), from a Public Health Unit (USP), having as its target the care process provided by nurses from the Grouping of Health Centers (ACeS) in the northern region. In order to understand this reality and the potential for intervention inherent to it, the Model of Evaluation, Intervention and Community Empowerment (MAIEC, Pedro Melo, 2016) was used. Thus, with the main objective of knowing the reality of VEDE in ACeS, where the internship took place, an observational, cross-sectional and descriptive study was carried out, in a universe of 262 nurses, with a sample consisting of 77 nurses. Based on the documental analysis of the Local Health Diagnosis and the Local Health Plan of ACeS, the main nursing phenomena were identified and the rates of documentation of these by nurses were determined. The results obtained show a low level of documentation of nursing diagnoses and diagnostic evaluation of the community management of ACeS on VEDE is compromised in all its diagnostic dimensions (community leadership, community participation and community process).


Asunto(s)
Enfermería en Salud Pública , Enfermería en Salud Comunitaria , Servicios de Salud Comunitaria , Empoderamiento , Investigación sobre Servicios de Salud
10.
Nanomaterials (Basel) ; 13(3)2023 Jan 18.
Artículo en Inglés | MEDLINE | ID: mdl-36770342

RESUMEN

Due to its several economic and ecological consequences, biofouling is a widely recognized concern in the marine sector. The search for non-biocide-release antifouling coatings has been on the rise, with carbon-nanocoated surfaces showing promising activity. This work aimed to study the impact of pristine graphene nanoplatelets (GNP) on biofilm development through the representative marine bacteria Cobetia marina and to investigate the antibacterial mechanisms of action of this material. For this purpose, a flow cytometric analysis was performed and a GNP/polydimethylsiloxane (PDMS) surface containing 5 wt% GNP (G5/PDMS) was produced, characterized, and assessed regarding its biofilm mitigation potential over 42 days in controlled hydrodynamic conditions that mimic marine environments. Flow cytometry revealed membrane damage, greater metabolic activity, and endogenous reactive oxygen species (ROS) production by C. marina when exposed to GNP 5% (w/v) for 24 h. In addition, C. marina biofilms formed on G5/PDMS showed consistently lower cell count and thickness (up to 43% reductions) than PDMS. Biofilm architecture analysis indicated that mature biofilms developed on the graphene-based surface had fewer empty spaces (34% reduction) and reduced biovolume (25% reduction) compared to PDMS. Overall, the GNP-based surface inhibited C. marina biofilm development, showing promising potential as a marine antifouling coating.

11.
Int J Mol Sci ; 23(23)2022 Nov 24.
Artículo en Inglés | MEDLINE | ID: mdl-36498973

RESUMEN

Marine biofouling is a natural process often associated with biofilm formation on submerged surfaces, creating a massive economic and ecological burden. Although several antifouling paints have been used to prevent biofouling, growing ecological concerns emphasize the need to develop new and environmentally friendly antifouling approaches such as bio-based coatings. Chitosan (CS) is a natural polymer that has been widely used due to its outstanding biological properties, including non-toxicity and antimicrobial activity. This work aims to produce and characterize poly (lactic acid) (PLA)-CS surfaces with CS of different molecular weight (Mw) at different concentrations for application in marine paints. Loligo opalescens pens, a waste from the fishery industry, were used as a CS source. The antimicrobial activity of the CS and CS-functionalized surfaces was assessed against Cobetia marina, a model proteobacterium for marine biofouling. Results demonstrate that CS targets the bacterial cell membrane, and PLA-CS surfaces were able to reduce the number of culturable cells up to 68% compared to control, with this activity dependent on CS Mw. The antifouling performance was corroborated by Optical Coherence Tomography since PLA-CS surfaces reduced the biofilm thickness by up to 36%, as well as the percentage and size of biofilm empty spaces. Overall, CS coatings showed to be a promising approach to reducing biofouling in marine environments mimicked in this work, contributing to the valorization of fishing waste and encouraging further research on this topic.


Asunto(s)
Antiinfecciosos , Incrustaciones Biológicas , Quitosano , Quitosano/farmacología , Incrustaciones Biológicas/prevención & control , Biopelículas , Pintura
12.
PLoS One ; 17(11): e0267530, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36413548

RESUMEN

BACKGROUND: Since the beginning of the COVID-19 pandemic, health professionals have been working under extreme conditions, increasing the risk of physical and mental illness. We evaluated the prevalence of burnout and its associated factors among postgraduate student residents in health professions during the global health crisis. METHODS: Healthcare residents were recruited from all across Brazil between July and September 2020 through digital forms containing instruments for assessing burnout (Oldenburg Burnout Inventory (OLBI)), resilience (brief resilient coping scale (BRCS)) and anxiety, stress and depression (depression, anxiety and stress scale (DASS-21) and Patient Health Questionnaire (PHQ-9)). Additionally, the relationships between burnout and chronic diseases, autonomy and educational adequacy in the residency programme, personal protective equipment (PPE), workload and care for patients with COVID-19 were evaluated. The chi-square test, Student's t test, Pearson's correlation test and logistic regression were performed. RESULTS: A total of 1,313 participants were included: mean (standard deviation) age, 27.8 (4.4) years; female gender, 78.1%; white race, 59.3%; and physicians, 51.3%. The overall prevalence of burnout was 33.4%. The odds (odds ratio [95% confidence interval]) of burnout were higher in the presence of pre-existing diseases (1.76 [1.26-2.47]) and weekly work > 60 h (1.36 [1.03-1.79]) and were lower in the presence of high resilience (0.84 [0.81-0.88]), autonomy (0.87 [0.81-0.93]), and educational structure (0.77 [0.73-0.82]), adequate availability of PPE (0.72 [0.63-0.83]) and non-white race (0.63 [0.47-0.83]). Burnout was correlated with anxiety (r = 0.47; p < 0.05), stress (r: 0.58; p < 0.05) and depression (r: 0.65; p < 0.05). CONCLUSIONS: We observed a high prevalence of burnout among residents during the COVID-19 pandemic. Individual characteristics and conditions related to the work environment were associated with a higher or lower occurrence of the syndrome.


Asunto(s)
Agotamiento Profesional , COVID-19 , Humanos , Femenino , Adulto , COVID-19/epidemiología , Prevalencia , Pandemias , Estudios Transversales , Agotamiento Profesional/epidemiología
13.
Polymers (Basel) ; 14(20)2022 Oct 19.
Artículo en Inglés | MEDLINE | ID: mdl-36297988

RESUMEN

The development of environmentally friendly antifouling strategies for marine applications is of paramount importance, and the fabrication of innovative nanocomposite coatings is a promising approach. Moreover, since Optical Coherence Tomography (OCT) is a powerful imaging technique in biofilm science, the improvement of its analytical power is required to better evaluate the biofilm structure under different scenarios. In this study, the effect of carbon nanotube (CNT)-modified surfaces in cyanobacterial biofilm development was assessed over a long-term assay under controlled hydrodynamic conditions. Their impact on the cyanobacterial biofilm architecture was evaluated by novel parameters obtained from three-dimensional (3D) OCT analysis, such as the contour coefficient, total biofilm volume, biovolume, volume of non-connected pores, and the average size of non-connected pores. The results showed that CNTs incorporated into a commercially used epoxy resin (CNT composite) had a higher antifouling effect at the biofilm maturation stage compared to pristine epoxy resin. Along with a delay in biofilm development, a decrease in biofilm wet weight, thickness, and biovolume was also achieved with the CNT composite compared to epoxy resin and glass (control surfaces). Additionally, biofilms developed on the CNT composite were smoother and presented a lower porosity and a strictly packed structure when compared with those formed on the control surfaces. The novel biofilm parameters obtained from 3D OCT imaging are extremely important when evaluating the biofilm architecture and behavior under different scenarios beyond marine applications.

14.
Antimicrob Agents Chemother ; 66(11): e0058322, 2022 11 15.
Artículo en Inglés | MEDLINE | ID: mdl-36286539

RESUMEN

The antileishmanial activity of a series of (Z)-2-(heteroarylmethylene)-3(2H)-benzofuranone derivatives, possessing 5-nitroimidazole or 4-nitroimidazole moieties, was investigated against Leishmania major promastigotes and some analogues exhibited prominent activities. Compounds with IC50 values lower than 20 µM were further examined against L. donovani axenic amastigotes. Evaluated analogues in 5-nitroimidazole subgroup demonstrated significantly superior activity (~17-88-folds) against L. donovani in comparison to L. major. (Z)-7-Methoxy-2-(1-methyl-5-nitroimidazole-2-ylmethylene)-3(2H)-benzofuranone (5n) showed the highest L. donovani anti-axenic amastigote activity with IC50 of 0.016 µM. The cytotoxicity of these analogues was determined using PMM peritoneal mouse macrophage and THP-1 human leukemia monocytic cell lines and high selectivity indices of 26 to 431 were obtained for their anti-axenic amastigote effect over the cytotoxicity on PMM cells. Further studies on their mode of action showed that 5-nitroimidazole compounds were bioactivated predominantly by nitroreductase 1 (NTR1) and 4-nitroimidazole analogues by both NTR1 and 2. It is likely that this bioactivation results in the production of nitroso and hydroxylamine metabolites that are cytotoxic for the Leishmania parasite.


Asunto(s)
Antiprotozoarios , Leishmania donovani , Nitroimidazoles , Humanos , Ratones , Animales , Antiprotozoarios/farmacología , Antiprotozoarios/metabolismo , Nitroimidazoles/farmacología , Nitroimidazoles/metabolismo , Macrófagos , Nitrorreductasas/metabolismo
15.
Int. j. cardiovasc. sci. (Impr.) ; 35(5): 646-656, Sept.-Oct. 2022. tab, graf
Artículo en Inglés | LILACS-Express | LILACS | ID: biblio-1405187

RESUMEN

Abstract Background Exercise training (ET) is an adjunctive treatment for obstructive sleep apnea (OSA) and its consequences. However, the effects of exercise on heart remodeling are unknown in the population with OSA. Objective We investigated the effect of ET on markers of diastolic function, sleep parameters, and functional capacity in patients with OSA. Methods Sedentary patients with OSA (apnea-hypopnea index, AHI ≥15 events/hr) were randomly assigned to untrained (n=18) and trained (n=20) strategies. Polysomnography, cardiopulmonary exercise test, and echocardiography were evaluated at the beginning and end of the study. ET consisted of 3 weekly sessions of aerobic exercise, resistance exercises, and flexibility training (72 sessions, completed in 11.65±0.86 months). A two-way analysis of variance (ANOVA) was used, followed by Tukey's post-hoc test. The level of statistical significance was set at p<0.05 for all analyses. Result Thirty-eight patients were included (AHI:45±29 events/hr, age:52±7 y, body mass index: 30±4 kg/m2). They had similar baseline parameters. ET caused a significant change in OSA severity (AHI:4.5±18 versus -5.7±13 events/hr; arousal index:1.5±8 versus -6.1±13 events/hr, in untrained and trained groups respectively, p<0.05). The trained patients had an increase in functional capacity after intervention. ET improved isovolumetric relaxation time (IVRT, untrained=6.5±17.3 versus trained=-5.1±17.1 msec, p<0.05). There was a significant correlation between changes in IVRT and arousal index in the trained group (r =-0.54, p<0.05). No difference occurred in the other diastolic function parameters evaluated. Conclusion ET promotes modest but significant improvement in AHI, functional capacity, and cardiac IVRT, a validated parameter of diastolic function.

16.
Bioorg Chem ; 127: 106009, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-35841672

RESUMEN

Leishmaniases have a broad spectrum of clinical manifestations, ranging from a cutaneous to a progressive and fatal visceral disease. Chemotherapy is nowadays the almost exclusive way to fight the disease but limited by its scarce therapeutic arsenal, on its own compromised by adverse side effects and clinical resistance. Cyclobenzaprine (CBP), an FDA-approved oral muscle relaxant drug has previously demonstrated in vitro and in vivo activity against Leishmania sp., but its targets were not fully unveiled. This study aimed to define the role of energy metabolism as a target for the leishmanicidal mechanisms of CBP. Methodology to assess CBP leishmanicidal mechanism variation of intracellular ATP levels using living Leishmania transfected with a cytoplasmic luciferase. Induction of plasma membrane permeability by assessing depolarization with DiSBAC(2)3 and entrance of the vital dye SYTOX® Green. Mitochondrial depolarization by rhodamine 123 accumulation. Mapping target site within the respiratory chain by oxygen consumption rate. Reactive oxygen species (ROS) production using MitoSOX. Morphological changes by transmission electron microscopy. CBP caused on L. infantum promastigotes a decrease of intracellular ATP levels, with irreversible depolarization of plasma membrane, the collapse of the mitochondrial electrochemical potential, mild uncoupling of the respiratory chain, and ROS production, with ensuing intracellular Ca2+ imbalance and DNA fragmentation. Electron microscopy supported autophagic features but not a massive plasma membrane disruption. The severe and irreversible mitochondrial damage induced by CBP endorsed the bioenergetics metabolism as a relevant target within the lethal programme induced by CBP in Leishmania. This, together with the mild-side effects of this oral drug, endorses CBP as an appealing novel candidate as a leishmanicidal drug under a drug repurposing strategy.


Asunto(s)
Antiprotozoarios , Leishmania infantum , Leishmaniasis Visceral , Adenosina Trifosfato/metabolismo , Amitriptilina/análogos & derivados , Animales , Antiprotozoarios/metabolismo , Metabolismo Energético , Humanos , Leishmaniasis Visceral/tratamiento farmacológico , Ratones , Ratones Endogámicos BALB C , Especies Reactivas de Oxígeno/metabolismo
17.
PLoS One ; 17(6): e0269318, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35709187

RESUMEN

BACKGROUND: In early 2020, the COVID-19 pandemic paralyzed the world and exposed the fragility of health systems in the face of mass illness. Health professionals became protagonists, fulfilling their mission at the risk of physical and mental illness. The study aimed to evaluate absenteeism indirectly related to SARS-CoV-2 infection in a large population of health care professionals. METHODS: An observational longitudinal repeated measures study was performed, including workers linked to 40 public university hospitals in Brazil. All causes of absenteeism were analyzed, focusing on those not directly attributed to COVID-19. Results for the same population were compared over two equivalent time intervals: prepandemic and during the pandemic. FINDINGS: A total of 32,691 workers were included in the study, with health professionals comprising 82.5% of the sample. Comparison of the periods before and during the pandemic showed a 26.6% reduction in work absence for all causes, except for COVID-19 and mental health-related absence. Concerning work absence related to mental health, the odds ratio was 39.0% higher during the pandemic. At the onset of the pandemic, there was an increase in absenteeism (all causes), followed by a progressive reduction until the end of the observation period. INTERPRETATION: Work absence related to mental illness among health care professionals increased during the COVID-19 pandemic, highlighting the need for health care managers to prioritize and implement support strategies to minimize absenteeism.


Asunto(s)
COVID-19 , Brasil/epidemiología , COVID-19/epidemiología , Personal de Salud/psicología , Hospitales Universitarios , Humanos , Salud Mental , Pandemias , SARS-CoV-2
18.
Eur J Cardiothorac Surg ; 61(6): 1283-1288, 2022 05 27.
Artículo en Inglés | MEDLINE | ID: mdl-35079781

RESUMEN

OBJECTIVES: Cardiopulmonary bypass generates a systemic inflammatory response. This inflammatory response is reduced if patients are ventilated during bypass, as evidenced by lower levels of postoperative circulating inflammatory mediators. However, this does not appear to make much clinical difference in adults, at least not consistently, but, to our knowledge, has never been assessed in paediatric cardiac surgery, which is the objective of this study. METHODS: This is a prospective clinical study of 12 consecutive neonates operated for the correction of either transposition of the great arteries ± ventricular septal defect or aortic arch hypoplasia ± ventricular septal defect, who were ventilated during cardiopulmonary bypass. These were compared to 11 neonates with the same malformations, who had undergone the same operations but without being ventilated during bypass (historical control group). RESULTS: One patient from the control group died on the 15th postoperative day due to sepsis and multi-organ failure. Bypass times and cross-clamp times were similar in the 2 groups. Ventilation on bypass was associated with significantly lower postoperative serum concentrations of C-reactive protein, shorter mechanical ventilation and lower vasoactive-inotropic score. Duration of stay on intensive care unit (ICU) showed a tendency to be shorter in patients who were ventilated on bypass, but this did not reach statistical significance. There were no differences between the 2 groups with respect to postoperative mixed venous oxygen saturations and serum concentrations of lactate and troponin I. CONCLUSIONS: Mechanical ventilation during cardiopulmonary bypass in neonates improves postoperative outcome.


Asunto(s)
Defectos del Tabique Interventricular , Transposición de los Grandes Vasos , Adulto , Puente Cardiopulmonar/efectos adversos , Puente Cardiopulmonar/métodos , Niño , Defectos del Tabique Interventricular/cirugía , Humanos , Recién Nacido , Estudios Prospectivos , Respiración Artificial , Transposición de los Grandes Vasos/cirugía , Resultado del Tratamiento
19.
Antimicrob Agents Chemother ; 66(1): e0153521, 2022 01 18.
Artículo en Inglés | MEDLINE | ID: mdl-34606338

RESUMEN

Phenotypic screening identified an arylsulfonamide compound with activity against Trypanosoma cruzi, the causative agent of Chagas' disease. Comprehensive mode of action studies revealed that this compound primarily targets the T. cruzi proteasome, binding at the interface between ß4 and ß5 subunits that catalyze chymotrypsin-like activity. A mutation in the ß5 subunit of the proteasome was associated with resistance to compound 1, while overexpression of this mutated subunit also reduced susceptibility to compound 1. Further genetically engineered and in vitro-selected clones resistant to proteasome inhibitors known to bind at the ß4/ß5 interface were cross-resistant to compound 1. Ubiquitinated proteins were additionally found to accumulate in compound 1-treated epimastigotes. Finally, thermal proteome profiling identified malic enzyme as a secondary target of compound 1, although malic enzyme inhibition was not found to drive potency. These studies identify a novel pharmacophore capable of inhibiting the T. cruzi proteasome that may be exploitable for anti-chagasic drug discovery.


Asunto(s)
Enfermedad de Chagas , Trypanosoma cruzi , Enfermedad de Chagas/tratamiento farmacológico , Descubrimiento de Drogas , Humanos , Complejo de la Endopetidasa Proteasomal/metabolismo , Inhibidores de Proteasoma/farmacología , Trypanosoma cruzi/química
20.
J Pharm Biomed Anal ; 209: 114469, 2022 Feb 05.
Artículo en Inglés | MEDLINE | ID: mdl-34838348

RESUMEN

Neglected tropical diseases (NTDs) such as visceral leishmaniasis (VL) present a limited and toxic therapeutic arsenal, and drug repositioning represents a safe and cost-effective approach. In this work, we investigated the antileishmanial potential and the mechanism of lethal action of the antidepressant escitalopram. The efficacy of escitalopram was determined ex-vivo using the intracellular Leishmania (L.) infantum amastigote model and the mammalian cytotoxicity was determined by the colorimetric MTT assay. The cellular and molecular alterations induced by the drug were investigated using spectrofluorimetry, a luminescence assay and flow cytometry. Our data revealed that escitalopram was active and selective against L. infantum parasites, with an IC50 value of 25 µM and a 50% cytotoxic concentration (CC50) of 184 µM. By using the fluorescent probes SYTOX® Green and DiSBAC2(3), the drug showed no alterations in the plasma membrane permeability nor in the electric potential of the membrane (∆ψp); however, after a short-time incubation, the drug caused a dose-dependent up-regulation of the calcium levels, leading to the depolarization of the mitochondrial membrane potential (∆ψm) and a reduction of the ATP levels. No up-regulation of reactive oxygen (ROS) was observed. In the cell cycle analysis, escitalopram induced a dose-dependent increase of the parasites at the sub G0/G1 stage, representing fragmented DNA. Escitalopram presented a selective antileishmanial activity, with disruption of single mitochondrion and interference in the cell cycle. Approved drugs such as escitalopram may represent a promising approach for NTDs and can be considered in future animal efficacy studies.


Asunto(s)
Antiprotozoarios , Leishmania infantum , Animales , Antidepresivos , Antiprotozoarios/farmacología , Escitalopram , Ratones , Ratones Endogámicos BALB C , Especies Reactivas de Oxígeno
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