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In this work, we experimentally analyzed and demonstrated the performance of an in-line Mach-Zehnder interferometer in the visible region, with an LED light source. The different waist diameter taper and asymmetric core-offset interferometers proposed used a single-mode fiber (SMF). The visibility achieved was V = 0.14 with an FSR of 23 nm for the taper MZI structure and visibilities of V = 0.3, V = 0.27, and V = 0.34 with FSRs of 23 nm, 17 nm, and 8 nm and separation lengths L of 2.5 cm, 4.0 cm, and 5.0 cm between the core-offset structure, respectively. The experimental investigation of the response to the temperature sensor yielded values from 50 °C to 300 °C; the sensitivity obtained was 3.53 a.u./°C, with R2 of 0.99769 and 1% every 1 °C in the transmission. For a range of 50 °C to 150 °C, 20.3 pm/°C with a R2 of 0.96604 was obtained.
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This research presents an experimental study focused on measuring temperature at the tool flank during the up-milling process at high cutting speed. The proposed system deals with emissivity compensation through a two-photodetector system and during calibration. A ratio pyrometer composed of two photodetectors and a multimode fiber-optic coupler is employed to capture the radiation emitted by the cutting insert. The pyrometer is calibrated using an innovative calibration system that addresses theoretical discrepancies arising from various factors affecting the measurement of cutting temperature. This calibration system replicates the milling process to generate a calibration curve. Experimentally, AISI 4140 steel is machined with coated tungsten carbide inserts, using cutting speeds of 300 and 400 m/min, and feed rates of 0.08 and 0.16 mm/tooth. The results reveal a maximum recorded cutting temperature of 518 °C and a minimum of 304 °C. The cutting temperature tends to increase with higher cutting speeds and feed rates, with cutting speed being the more influential factor in this increase. Both the pyrometer calibration and experimental outcomes yield satisfactory results. Finally, the results showed that the process and the device prove to be a convenient, effective, and precise method of measuring cutting temperature in machine processes.
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One problem in the quantitative assessment of biomechanical impairments in Parkinson's disease patients is the need for scalable and adaptable computing systems. This work presents a computational method that can be used for motor evaluations of pronation-supination hand movements, as described in item 3.6 of the Unified Parkinson's Disease Rating Scale (MDS-UPDRS). The presented method can quickly adapt to new expert knowledge and includes new features that use a self-supervised training approach. The work uses wearable sensors for biomechanical measurements. We tested a machine-learning model on a dataset of 228 records with 20 indicators from 57 PD patients and eight healthy control subjects. The test dataset's experimental results show that the method's precision rates for the pronation and supination classification task achieved up to 89% accuracy, and the F1-scores were higher than 88% in most categories. The scores present a root mean squared error of 0.28 when compared to expert clinician scores. The paper provides detailed results for pronation-supination hand movement evaluations using a new analysis method when compared to the other methods mentioned in the literature. Furthermore, the proposal consists of a scalable and adaptable model that includes expert knowledge and affectations not covered in the MDS-UPDRS for a more in-depth evaluation.
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The coordination of one and two aflatoxin B1 (AFB1, a potent carcinogen) molecules with chlorophyll a (chl a) was studied at a theoretical level. Calculations were performed using the M06-2X method in conjunction with the 6-311G(d,p) basis set, in both gas and water phases. The molecular electrostatic potential map shows the chemical activity of various sites of the AFB1 and chl a molecules. The energy difference between molecular orbitals of AFB1 and chl a allowed for the establishment of an intermolecular interaction. A charge transfer from AFB1 to the central cation of chl a was shown. The energies of the optimized structures for chl a show two configurations, unfolded and folded, with a difference of 15.41 kcal/mol. Chl a appeared axially coordinated to the plane (α-down or ß-up) of the porphyrin moiety, either with the oxygen atom of the ketonic group, or with the oxygen atom of the lactone moiety of AFB1. The complexes of maximum stability were chl a 1-α-E-AFB1 and chl a 2-ß-E-AFB1, at -36.4 and -39.2 kcal/mol, respectively. Additionally, with two AFB1 molecules were chl a 1-D-2AFB1 and chl a 2-E-2AFB1, at -60.0 and -64.8 kcal/mol, respectively. Finally, biosorbents containing chlorophyll could improve AFB1 adsorption.
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Aflatoxina B1 , Clorofila , Aflatoxina B1/química , Carcinógenos , Clorofila A , OxigênioRESUMO
Research background: Tomato (Solanum lycopersicum L.) fruit is highly consumed worldwide and contains high amounts of carotenoids and tocopherols, two powerful antioxidants. Native tomato genotypes are rarely used in large-scale market but serve as a reservoir to diversify the species gene pool and can be employed to obtain functional compounds. Extraction methods are currently changing towards cleaner procedures that are more efficient and environmentally friendly, including avoiding toxic or polluting solvents. Experimental approach: In this study, factorial and fractional factorial designs were used to evaluate the efficiency of digestive enzymes, sonication and green solvents to obtain lipophilic antioxidant extracts from native tomato. To monitor the efficiency of the extraction process, spectrophotometric quantification of total carotenoids and antioxidant activity was carried out, and then individual quantification of carotenoids and tocopherols in the extracts was done by HPLC. Results and conclusions: Digestive enzymes and sonication increased the carotenoid content and the antioxidant activity of the obtained extracts when applied individually. However, when these treatments were applied together and in combination with isopropyl acetate, a green solvent, the obtained extracts had the highest carotenoid and tocopherol contents as well as the maximal antioxidant activity. A correlation analysis suggested that antioxidant activity resulted from synergistic effects rather than individual compounds. Tomato extracts were obtained through a rapid and environmentally friendly extraction method and their antioxidant activity was enhanced. Novelty and scientific contribution: Tomato fruits have been the subject of numerous studies; however, functional compound extraction through environmentally friendly methods remains an attractive use of native tomato fruit, enhancing its limited production and harnessing a large amount of tomato product industry. There are few reports where environmentally friendly extraction methods are combined; even rarer are those where green solvents are also used. In this work, the combination of different environmentally friendly extraction methods improved the extraction of carotenoids and tocopherols and allowed to establish a more efficient process. These results could stimulate the use of clean technologies and make the native tomato more attractive for industrial or compound extraction processes.
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The role of circumcision in partially protecting against sexually transmitted infections (STIs) and other dermatoses has been documented. Neonatal circumcision is not routinely practiced in South America. Although it is logical to assume that male genital dermatoses are more prevalent in Hispanic men, they are underrepresented in the existing literature. Objective: To describe the epidemiological characteristics from our male genital dermatology unit in Montevideo (Uruguay), the diagnoses, and correlate them with circumcision status and comorbidities. Methods: A retrospective observational cohort study was conducted. A dermatologist and urologist evaluated all patients using standard questionnaires. In 3 years and 8 months, 269 patients were seen. Median age was 41, prevalence of neonatal circumcision was 0.7%, HIV was 4.2%, STIs were 24.9%, non-STIs were 63.9%, and both (STI + non-STI) were 11.2%. Most frequent entities: eczema/balanoposthitis (27.1%), condyloma (24.9%), and lichen sclerosus (15.6%). Data correlating circumcision and other diagnoses did not reach statistical significance. HIV was positively associated with other STIs (p < 0.05), and an association with balanoposthitis was seen; however, it did not reach statistical significance (p < 0.1). Main limitation was small sample size. This is the first study of its kind based on Hispanic patients. Collaboration between specialties proved to be fundamental. Further studies are needed in this demographic to find an association between circumcision, comorbidities, and genital dermatoses.
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Circuncisão Masculina , Dermatologia , Adulto , Genitália , Hispânico ou Latino , Humanos , Recém-Nascido , Masculino , Estudos RetrospectivosRESUMO
Employing theoretical calculations with density functional theory (DFT) using the B3LYP/6-311++G(d,p) functional and basis set, the interaction of the aflatoxin B1 (AFB1) molecule and the functional groups present in the Pyracantha koidzumii biosorbent was investigated. Dissociation free energy and acidity equilibrium constant values were obtained theoretically both in solution (water) and gas phases. Additionally, the molecular electrostatic potential for the protonated molecules was calculated to verify the reactivity. Thus, methanol (hydroxyl group), methylammonium ion (amino group), acetate ion (carboxyl group), and acetone (carbonyl group), were used as representatives of the substrates present in the biomass; these references were considered using the corresponding protonated or unprotonated forms at a pH value of 5. The experimental infrared spectrophotometric data suggested the participation of these functional groups in the AFB1 biosorption process, indicating that the mechanism was dominated by electrostatic interactions between the charged functional groups and the positively charged AFB1 molecule. The theoretical determination indicated that the carboxylate ion provided the highest interaction energy with the AFB1 molecule. Consequently, an enriched biosorbent with compounds containing carboxyl groups could improve the yield of the AFB1 adsorption when using in vitro and in vivo trials.
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Aflatoxina B1/química , Descontaminação , Teoria da Densidade Funcional , Modelos Químicos , Pyracantha/química , Adsorção , Aflatoxina B1/metabolismo , Ligação de Hidrogênio , Estrutura Molecular , Prótons , Pyracantha/metabolismo , Espectrofotometria Infravermelho , Eletricidade Estática , Relação Estrutura-AtividadeRESUMO
Many natural phyto-products as perezone (Per) exhibit anti-cancer activities. Using experimental and computational studies, it was described that Poly ADP-ribose polymerase 1(PARP-1) inhibition and the induction of oxidative stress state explain the pro-apoptotic activity of Per. The aim of this study was to evaluate two phyto-products related to Per as anti-cancer agents: hydroxyperezone (OHPer) and its monoangelate (OHPer-MAng). These molecules were structurally characterized employing thermal analysis, IR spectrophotometry and X-ray diffraction techniques. The phyto-compounds evaluated in vitro in six cancer cell lines (K562, MCF-7, MDA-MB-231, HeLa, U373, A549) and non-malignant cells determinate their cytotoxicity, type of induced cell death, ability to avoid cell migration and changes at the redox status of the cell. Using, in vitro and computational studies provided the inhibition of PARP-1 and its potential binding mode. Cell proliferation assays demonstrated that OHPer-MAng treatment significantly induces apoptosis in triple negative breast cancer (TNBC) cell line (MDA-MB-231 IC50 = 3.53 µM), being particularly less cytotoxic to Vero cells (IC50 = 313.92 µM), human lymphocytes (IC50 = 221.46 µM) and rat endothelial cells (IC50=> 400 µM). The treatment of MDA-MB-231 cells with OHPer-MAng showed inhibition of migration by cancer cells. The induction of an oxidative stress state, similar to other quinones and PARP-1 inhibition explains the pro-apoptotic activity of OHPer-MAng. Docking studies showed that OHPer-MAng establishes great non-bonding interactions with the lateral chains of Tyr235, Hys201, Tyr246, Ser203, Asn207, and Gly233 located at the catalytic site of PARP-1, also demonstrating the anti-cancer activity of OHPer-MAng in TNBC cell line.
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Antineoplásicos/farmacologia , Asteraceae/química , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Cicloexenos/farmacologia , Extratos Vegetais/farmacologia , Sesquiterpenos/farmacologia , Animais , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Chlorocebus aethiops , Cicloexenos/química , Células Endoteliais , Humanos , Ratos , Sesquiterpenos/química , Células VeroRESUMO
Mucor circinelloides is a dimorphic Zygomycete fungus that produces ethanol under aerobic conditions in the presence of glucose, which indicates that it is a Crabtree-positive fungus. To determine the physiological role of the alcohol dehydrogenase (ADH) activity elicited under these conditions, we obtained and characterized an allyl alcohol-resistant mutant that was defective in ADH activity, and examined the effect of adh mutation on physiological parameters related to carbon and energy metabolism. Compared to the Adh+ strain R7B, the ADH-defective (Adh-) strain M5 was unable to grow under anaerobic conditions, exhibited a considerable reduction in ethanol production in aerobic cultures when incubated with glucose, had markedly reduced growth capacity in the presence of oxygen when ethanol was the sole carbon source, and exhibited very low levels of NAD+-dependent alcohol de-hydrogenase activity in the cytosolic fraction. Further characterization of the M5 strain showed that it contains a 10-bp deletion that interrupts the coding region of the adhl gene. Complementation with the wild-type allele adh1+ by transformation of M5 remedied all the defects caused by the adh1 mutation. These findings indicate that in M. circinelloides, the product of the adh1 gene mediates the Crabtree effect, and can act as either a fermentative or an oxidative enzyme, depending on the nutritional conditions, thereby participating in the association between fermentative and oxidative metabolism. It was found that the spores of M. circinelloides possess low mRNA levels of the ethanol assimilation genes (adl2 and acs2), which could explain their inability to grow in the alcohol.
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Álcool Desidrogenase/fisiologia , Etanol/metabolismo , Glucose/metabolismo , Mucor/enzimologia , Álcool Desidrogenase/genética , Metabolismo Energético , Fermentação , Mucor/genética , OxirreduçãoRESUMO
BACKGROUND: Type 2 diabetes mellitus (T2D) is a leading cause of morbidity and mortality in Mexico. Here, we aimed to report incidence rates (IR) of type 2 diabetes in middle-aged apparently-healthy Mexican adults, identify risk factors associated to ID and develop a predictive model for ID in a high-risk population. METHODS: Prospective 3-year observational cohort, comprised of apparently-healthy adults from urban settings of central Mexico in whom demographic, anthropometric and biochemical data was collected. We evaluated risk factors for ID using Cox proportional hazard regression and developed predictive models for ID. RESULTS: We included 7636 participants of whom 6144 completed follow-up. We observed 331 ID cases (IR: 21.9 per 1000 person-years, 95%CI 21.37-22.47). Risk factors for ID included family history of diabetes, age, abdominal obesity, waist-height ratio, impaired fasting glucose (IFG), HOMA2-IR and metabolic syndrome. Early-onset ID was also high (IR 14.77 per 1000 person-years, 95%CI 14.21-15.35), and risk factors included HOMA-IR and IFG. Our ID predictive model included age, hypertriglyceridemia, IFG, hypertension and abdominal obesity as predictors (Dxy = 0.487, c-statistic = 0.741) and had higher predictive accuracy compared to FINDRISC and Cambridge risk scores. CONCLUSIONS: ID in apparently healthy middle-aged Mexican adults is currently at an alarming rate. The constructed models can be implemented to predict diabetes risk and represent the largest prospective effort for the study metabolic diseases in Latin-American population.
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Biomarcadores/análise , Diabetes Mellitus Tipo 2/diagnóstico , Diabetes Mellitus Tipo 2/epidemiologia , Síndrome Metabólica/fisiopatologia , Modelos Estatísticos , Medição de Risco/métodos , Adulto , Algoritmos , Estudos de Casos e Controles , Feminino , Seguimentos , Intolerância à Glucose/diagnóstico , Intolerância à Glucose/epidemiologia , Humanos , Masculino , México/epidemiologia , Pessoa de Meia-Idade , Estado Pré-Diabético/diagnóstico , Estado Pré-Diabético/epidemiologia , Valor Preditivo dos Testes , Prognóstico , Estudos Prospectivos , Fatores de RiscoRESUMO
Parkinson's disease (PD) is a progressive disorder that affects motor regulation. The Unified Parkinson's Disease Rating Scale sponsored by the Movement Disorder Society (MDS-UPDRS) quantifies the illness progression based on clinical observations. The leg agility is an item in this scale, yet only a visual detection of the features is used, leading to subjectivity. Overall, 50 patients (85 measurements) with varying motor impairment severity were asked to perform the leg agility item while wearing inertial sensor units on each ankle. We quantified features based on the MDS-UPDRS and designed a fuzzy inference model to capture clinical knowledge for assessment. The model proposed is capable of capturing all details regardless of the task speed, reducing the inherent uncertainty of the examiner observations obtaining a 92.35% of coincidence with at least one expert. In addition, the continuous scale implemented in this work prevents the inherent "floor/ceil" effect of discrete scales. This model proves the feasibility of quantification and assessment of the leg agility through inertial signals. Moreover, it allows a better follow-up of the PD patient state, due to the repeatability of our computer model and the continuous output, which are not objectively achievable through visual examination. Graphical abstract á .
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Perna (Membro)/fisiopatologia , Doença de Parkinson/fisiopatologia , Simulação por Computador , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Índice de Gravidade de DoençaRESUMO
RESUMEN La investigación que se presenta es resultante del quehacer cotidiano del colectivo de entrenadores que labora en la Academia Provincial de Boxeo en la provincia de Sancti Spíritus. El problema que se investiga responde a las demandas tecnológicas que existen a nivel provincial, teniendo como objetivo aplicar un conjunto de acciones técnico-tácticas para la elevación del nivel de preparación de los boxeadores espirituanos que permita la obtención de resultados satisfactorios en el orden competitivo. La muestra utilizada la componen 20 boxeadores categoría élite de la provincia de Sancti Spíritus. En el proceso investigativo se emplearon métodos teóricos, empíricos y matemáticos estadísticos, entre ellos: histórico-lógico, análisis síntesis, inductivo deductivo, observación, entrevista, el pre-experimento y la estadística descriptiva. Se realizó un diagnóstico a partir de los resultados de las pruebas técnicas de la participación de la muestra en los Campeonatos Nacionales Playa Girón, en el ciclo 2013-2016. Los resultados finales se comparan con los emitidos por los especialistas de la Comisión Técnica Nacional en el Campeonato Nacional Playa Girón, celebrado en el mes de diciembre de 2017, en la Sala Yara de la provincia de Sancti Spíritus. Los logros se corresponden con el trabajo realizado de forma colectiva e individual a partir de las carencias y potencialidades que presentan los boxeadores espirituanos investigados. Se pudo demostrar que teniendo en cuenta el comportamiento de las principales dimensiones e indicadores de las pruebas técnicas, se pueden obtener buenos resultados competitivos, además de facilitar el trabajo diferenciado con cada boxeador.
ABSTRACT The investigative work presented is part of the daily work of the group of trainers that works in the Provincial Boxing Academy in the province of Sancti Spíritus. The problem investigated responds to the technological demands that exist at the provincial level, with the objective of applying a set of technical-tactical actions to raise the level of preparation of the boxers of Sancti Spiritus that allows obtaining satisfactory results in the competitive order. The diagnosis was developed based on the results of the technical tests of the participation of the boxers from Sancti Spiritus in the Playa Girón National Championships in the 2013-2016 cycle. The final results are compared with those issued by the specialists of the National Technical Commission in the present Playa Girón National Championship held in December 2017, in the Sala Yara of the Province of Sancti Spíritus. The population that was used for this investigation is made up of 20 elite category boxers from the province of Sancti Spíritus. The achievements correspond to the work done collectively and individually from the shortcomings and potentials presented by the investigated boxers from Sancti Spiritus. Therefore, it was possible to demonstrate that taking into account the behavior of the main dimensions and indicators of the technical tests, good competitive results can be obtained and that it facilitated the differentiated work with each boxer taking into account the scientific and technical advances at our disposal. In order to comply with this research, theoretical, empirical and mathematical mathematical methods were used; among which we can mention: Historical-logical, synthesis analysis, inductive deductive, observation, interview, pre-experiment and descriptive statistics.
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Background: Smoking and smoke from biomass burning (BB) are the main environmental risk factors for COPD. Clinical differences have been described between COPD related to smoking and related to wood smoke, but no studies have shown genetic differences between patients exposed to these two risk factors. Methods: To investigate a possible association of tumor necrosis factor (TNF) promoter polymorphisms, we conducted a case-control study. A total of 1,322 subjects were included in four groups: patients with a diagnosis of COPD secondary to smoking (COPD-S, n=384), patients with COPD secondary to biomass burning (COPD-BB, n=168), smokers without COPD (SWOC, n=674), and biomass burning-exposed subjects (BBES n=96). Additionally, a group of 950 Mexican mestizos (MMs) was included as a population control. Three single nucleotide polymorphisms (SNPs) were selected in the TNF gene (rs1800629, rs361525, and rs1800750) and one SNP in the lymphotoxin alpha gene (rs909253). Results: Statistically significant differences were found with genotype GA of the rs1800629: COPD-S vs SWOC, (p<0.001, odds ratio [OR] =2.55, 95% CI=1.53-4.27); COPD-S vs COPD-BB (p,0.01). When performing the comparison of the less severe (G1: I + II) and the more severe (G2: III + IV) levels, differences were identified in G1 (p<0.05, OR=1.94, 95% CI=1.04-3.63) and G2 (p<0.001, OR=3.68, 95% CI=1.94-3.07) compared with SWOC. Regarding genotype GA of rs361525, it has been associated when comparing COPD-BB vs BBES (p=0.0079, OR=5.99, 95% CI=1.38-53.98). Conclusion: The heterozygous genotype GA of polymorphisms rs1800629 and rs361525 in the TNF promoter are associated with the risk of COPD.
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Biomassa , Interação Gene-Ambiente , Pulmão/fisiopatologia , Polimorfismo de Nucleotídeo Único , Regiões Promotoras Genéticas , Doença Pulmonar Obstrutiva Crônica/genética , Fumar Tabaco/efeitos adversos , Fator de Necrose Tumoral alfa/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Casos e Controles , Distribuição de Qui-Quadrado , Feminino , Frequência do Gene , Estudos de Associação Genética , Predisposição Genética para Doença , Heterozigoto , Homozigoto , Humanos , Linfotoxina-alfa/genética , Masculino , México/epidemiologia , Pessoa de Meia-Idade , Razão de Chances , Fenótipo , Doença Pulmonar Obstrutiva Crônica/diagnóstico , Doença Pulmonar Obstrutiva Crônica/epidemiologia , Doença Pulmonar Obstrutiva Crônica/fisiopatologia , Fatores de Risco , Fumar Tabaco/fisiopatologia , Madeira/efeitos adversosRESUMO
Spondias purpurea L. is a fruit native to Mexico, however, it is found as far away as Brazil. It possesses a high commercial potential owing to its sensorial and nutritional qualities and its low cost of production. There exists a variety of ecotypes that have not been characterized and their adequate selection process, according to their strongest functional characteristics, will allow the establishment of improvement programs for this genetic resource. The object of this study was the chemical characterization and the determination of the in vitro and in vivo antioxidant capacity of 7 Spondias purpurea L. ecotypes. Differences were observed in the antioxidant capacity and the content of functional compounds among all the ecotypes analyzed. A high total phenolic content and a low flavonoid and carotenoid content were found, both in the epicarp and in the pulp. In each ecotype, the hydrophilic phase presented up to 40 times greater antioxidant capacity compared to the lipophilic phase. The hydrophilic phase of the epicarp of "Costeña Tierra Colorada" had the greatest antioxidant capacity and highest total phenolic content, whereas "Jocote" presented the lowest antioxidant capacity and total phenolic content. A positive correlation was observed between phenol levels and the antioxidant capacity in the epicarp. Regarding antioxidant activity in vivo, it was observed that in all analyzed concentrations of hydrophilic extracts of the epicarp of "Costeña Tierra Colorada" and in the highest "Jocote" concentrations, they provided thermo-protection against heat stress as well as a general well-being to the worm as evidenced by their high mobility.
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Anacardiaceae/química , Antioxidantes/análise , Ecótipo , Frutas/química , Brasil , Carotenoides/análise , Flavonoides/análise , México , Fenóis/análise , Extratos Vegetais/química , Especificidade da EspécieRESUMO
Thirty-three meso-dihydroguaiaretic acid (meso-DGA) derivatives bearing esters, ethers, and amino-ethers were synthesized. All derivatives were tested against twelve drug-resistant clinical isolates of Gram-positive and Gram-negative bacteria, including sensitive (H37Rv) and multidrug-resistant Mycobacterium tuberculosis strains. Among the tested compounds, four esters (7, 11, 13, and 17), one ether (23), and three amino-ethers (30, 31, and 33) exhibited moderate activity against methicillin-resistant Staphylococcus aureus, whereas 30 and 31 showed better results than levofloxacin against vancomycin-resistant Enterococcus faecium. Additionally, nineteen meso-DGA derivatives displayed moderate to potent activity against M. tuberculosis H37Rv with minimum inhibitory concentration (MIC) values ranging from 3.125 to 50µg/mL. Seven meso-DGA derivatives bearing amino-ethers (26-31 and 33) exhibited the lowest MICs against M. tuberculosis H37Rv and G122 strains, with 31 being as potent as ethambutol (MICs of 3.125 and 6.25µg/mL). The presence of positively charged group precursors possessing steric and hydrophobic features (e.g. N-ethylpiperidine moieties in meso-31) resulted essential to significantly increase the antimycobacterial properties of parent meso-DGA as supported by the R-group pharmacophoric and field-based QSAR analyses. To investigate the safety profile of the antimycobacterial compounds, cytotoxicity on Vero cells was determined. The amino-ether 31 exhibited a selectivity index value of 23, which indicate it was more toxic to M. tuberculosis than to mammalian cells. Therefore, 31 can be considered as a promising antitubercular agent for further studies.
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Antibacterianos/farmacologia , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Guaiacol/análogos & derivados , Lignanas/farmacologia , Animais , Antibacterianos/síntese química , Antibacterianos/química , Sobrevivência Celular/efeitos dos fármacos , Chlorocebus aethiops , Relação Dose-Resposta a Droga , Guaiacol/síntese química , Guaiacol/química , Guaiacol/farmacologia , Lignanas/síntese química , Lignanas/química , Testes de Sensibilidade Microbiana , Estrutura Molecular , Relação Quantitativa Estrutura-Atividade , Células VeroRESUMO
This paper presents a new method based on Estimation of Distribution Algorithms (EDAs) to detect parabolic shapes in synthetic and medical images. The method computes a virtual parabola using three random boundary pixels to calculate the constant values of the generic parabola equation. The resulting parabola is evaluated by matching it with the parabolic shape in the input image by using the Hadamard product as fitness function. This proposed method is evaluated in terms of computational time and compared with two implementations of the generalized Hough transform and RANSAC method for parabola detection. Experimental results show that the proposed method outperforms the comparative methods in terms of execution time about 93.61% on synthetic images and 89% on retinal fundus and human plantar arch images. In addition, experimental results have also shown that the proposed method can be highly suitable for different medical applications.
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Simulação por Computador , Pé/diagnóstico por imagem , Retina/diagnóstico por imagem , Vasos Retinianos/diagnóstico por imagem , Algoritmos , Pé/fisiologia , Fundo de Olho , Humanos , Interpretação de Imagem Assistida por Computador/métodos , Retina/fisiologia , Processamento de Sinais Assistido por Computador , Software , Fatores de TempoRESUMO
Theoretical studies of 8-chloro-9-hydroxy-aflatoxin B1 (2) were carried out by Density Functional Theory (DFT). This molecule is the reaction product of the treatment of aflatoxin B1 (1) with hypochlorous acid, from neutral electrolyzed water. Determination of the structural, electronic and spectroscopic properties of the reaction product allowed its theoretical characterization. In order to elucidate the formation process of 2, two reaction pathways were evaluated-the first one considering only ionic species (Cl⺠and OH(-)) and the second one taking into account the entire hypochlorous acid molecule (HOCl). Both pathways were studied theoretically in gas and solution phases. In the first suggested pathway, the reaction involves the addition of chlorenium ion to 1 forming a non-classic carbocation assisted by anchimeric effect of the nearest aromatic system, and then a nucleophilic attack to the intermediate by the hydroxide ion. In the second studied pathway, as a first step, the attack of the double bond from the furanic moiety of 1 to the hypochlorous acid is considered, accomplishing the same non-classical carbocation, and again in the second step, a nucleophilic attack by the hydroxide ion. In order to validate both reaction pathways, the atomic charges, the highest occupied molecular orbital and the lowest unoccupied molecular orbital were obtained for both substrate and product. The corresponding data imply that the C9 atom is the more suitable site of the substrate to interact with the hydroxide ion. It was demonstrated by theoretical calculations that a vicinal and anti chlorohydrin is produced in the terminal furan ring. Data of the studied compound indicate an important reduction in the cytotoxic and genotoxic potential of the target molecule, as demonstrated previously by our research group using different in vitro assays.
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Aflatoxinas/química , Modelos Químicos , Água/química , Aflatoxinas/toxicidade , Eletrólise , Gases , Ácido Hipocloroso/química , Modelos Moleculares , Estrutura Molecular , Espectroscopia de Prótons por Ressonância Magnética , Soluções , Relação Estrutura-Atividade , TermodinâmicaRESUMO
Presently the search for new drugs from natural resources is of growing interest to the pharmaceutical industry. Natural products have been the source of new drugs since ancient times. Plants are a good source of secondary metabolites which have been found to have beneficial properties. The present study is a review of the chemistry and pharmacology of Citrus sinensis. This review reveals the therapeutic potential of C. sinensis as a source of natural compounds with important activities that are beneficial for human health that could be used to develop new drugs.
Assuntos
Produtos Biológicos/química , Citrus sinensis/química , Descoberta de Drogas , Produtos Biológicos/uso terapêutico , HumanosRESUMO
Chronic obstructive pulmonary disease (COPD) is an inflammatory disease that arises in response to noxious particles or gases. Associations of genetic polymorphisms in TNF have been reported in Asians and Caucasians, but not in Mestizo populations. A case-control study was conducted in two stages: in the first stage, patients with COPD (COPD group, n=165) and smokers without disease (SNC group, n=165) were included and the TNF promoter sequence was determined using direct sequencing. In the second stage, the identified polymorphisms were validated by real-time polymerase chain reaction (PCR) in COPD (n=260) and SNC (n=506). In the first stage, 11 different sets of "contig" alignments were determined, of which contig 10 was found to be associated with susceptibility (P=5.0E-04, OR [odds ratio] =3.64) and contig 1 with Global Initiative for COPD (GOLD) greater grade (P=1.0E-02, OR =3.82). The single nucleotide polymorphisms found in this region were individually identified; the GA genotypes of rs1800629 (P=0.038, OR =2.07), rs56036015 (P=0.0082, OR =3.18), and rs361525 (P=1.0E-02, OR =4.220) were higher in the COPD group vs the SNC group; after second-stage validation, rs1800629 (P=6.00E-03, OR =2.26) and rs56036015 (P=1.10E-03, OR =2.54) are maintained. There are genetic variants in the TNF promoter associated with increased risk of COPD secondary to smoking and with a higher GOLD grade in the Mexican Mestizo population.
Assuntos
Polimorfismo de Nucleotídeo Único , Regiões Promotoras Genéticas , Doença Pulmonar Obstrutiva Crônica/genética , Fumar/efeitos adversos , Fator de Necrose Tumoral alfa/genética , Idoso , Estudos de Casos e Controles , Distribuição de Qui-Quadrado , Feminino , Volume Expiratório Forçado , Interação Gene-Ambiente , Predisposição Genética para Doença , Humanos , Pulmão/fisiopatologia , Masculino , México/epidemiologia , Pessoa de Meia-Idade , Razão de Chances , Fenótipo , Doença Pulmonar Obstrutiva Crônica/diagnóstico , Doença Pulmonar Obstrutiva Crônica/etnologia , Doença Pulmonar Obstrutiva Crônica/fisiopatologia , Reação em Cadeia da Polimerase em Tempo Real , Fatores de Risco , Índice de Gravidade de Doença , Fumar/etnologia , Capacidade VitalRESUMO
Bacterial infections represent one of the main threats to global public health. One of the major causative agents associated with high morbidity and mortality infections in hospitals worldwide is methicillin-resistant Staphylococcus aureus. Therefore, there is a need to develop new antibacterial agents to treat these infections, and natural products are a rich source of them. In previous studies, we reported that lignan 3'-demethoxy-6-O-demethylisoguaiacin, isolated and characterized from Larrea tridentate, showed the best activity towards methicillin-resistant S. aureus. Thus, the aim of this study was to determine the potential molecular mechanism of the antibacterial activity of 3'-demethoxy-6-O-demethylisoguaiacin against methicillin-resistant S. aureus using microarray technology. Results of microarray genome expression were validated by real-time polymerase chain reaction (RT-PCR). The genetic profile expression results showed that lignan 3'-demethoxy-6-O-demethylisoguaiacin had activity on cell membrane affecting proteins of the ATP-binding cassette (ABC) transport system causing bacteria death. This molecular mechanism is not present in any antibacterial commercial drug and could be a new target for the development of novel antibacterial agents.