RESUMO
Folate-mediated one-carbon metabolism (FOCM) plays an important role in colorectal carcinogenesis. Previous studies have assessed the role of folate-mediated one-carbon metabolism (FOCM)-related gene-diet interaction in the aetiology of colorectal cancer (CRC), however, the results remained inconclusive. Thus, this study aimed to investigate dietary factors and genetic variants related to FOCM, as well as potential nutrient-gene and nutrient-lifestyle interactions, on CRC risk. This observational study included 229 patients diagnosed with CRC and 229 age- and sex-matched subjects as controls from a population-based bowel cancer screening program. Conditional logistic regression was used to calculate odds ratios (ORs) and 95% confidence intervals (95%CI) for CRC risk. A Bonferroni-corrected threshold of α = 0.005 was considered significant, and P values less than 0.05 were considered to be suggestive of an association. After Bonferroni correction, a high dietary intake of betaine was associated with a decreased risk of CRC in the adjusted model (OR, 95% CI: 0.21, 0.10-0.40, P < 0.001). Two SNPs, rs1476413 and rs17824591, exhibited significant gene-diet interactions with total choline ad vitamin B12 intakes, respectively, in adjusted models (total choline, tertile 3 vs. 1, OR, 95% CI: 0.25, 0.11-0.66, Pinteraction = 0.012; vitamin B12, tertile 2 vs. tertile 1, OR, 95% CI: 2.48, 1.04-5.00, Pinteraction = 0.003). These findings suggest that betaine intake and interactions between some dietary factors and variants in MTHFR and MTHFD1 genes have an influence on CRC risk in the population studied. If these results are confirmed, specific nutritional intervention strategies could be designed.
Assuntos
Neoplasias Colorretais , Dieta , Ácido Fólico , Polimorfismo de Nucleotídeo Único , Humanos , Neoplasias Colorretais/genética , Estudos de Casos e Controles , Ácido Fólico/administração & dosagem , Ácido Fólico/metabolismo , Feminino , Masculino , Pessoa de Meia-Idade , Dieta/métodos , Dieta/estatística & dados numéricos , Idoso , Fatores de Risco , Espanha/epidemiologia , Metilenotetra-Hidrofolato Redutase (NADPH2)/genética , Betaína/administração & dosagem , Betaína/metabolismo , Metilenotetra-Hidrofolato Desidrogenase (NADP)/genética , Predisposição Genética para Doença , Razão de Chances , Nutrientes/administração & dosagemRESUMO
A family of acylhydrazones have been prepared and characterized with the aim of investigating their potential as information storage systems. Their well-established synthetic methodologies allowed for the preparation of seven chemically stable acylhydrazones in excellent yields that have been photophysically and photochemically characterized. In addition, DFT and TD-DFT calculations have been performed to gain more insights into the structural, energetic and photophysical properties of the E/Z isomers. Our results reveal that E/Z configurational isomerization upon irradiation is highly dependent on the stabilization of the E or Z isomers due to the formation of intramolecular H bonds and the electronic/steric effects intrinsically related to their structures. In addition, Raman spectroscopy is also used to confirm the molecular structural changes after the formation of hydrogen bonds in the isomers.
Assuntos
Análise Espectral Raman , Modelos Moleculares , Isomerismo , Espectroscopia de Ressonância Magnética , Teoria da Densidade FuncionalRESUMO
Secondary/persistent infections are present in teeth with previous root canal treatment, and a great variety of anaerobic microorganisms has been observed in these infections. The antibiotics prescription is occasional; however, in some cases, it is essential, particularly when the general health condition of the patient is compromised. The aims of this study were to identify the associated microorganisms in diagnosis of persistent or secondary apical periodontitis and to evaluate the susceptibility level to the antibiotics most used. Fifteen patients with persistent or secondary apical periodontitis requiring endodontic re-treatment were included. Microbiological samples were taken from the root canals and incubated in thioglycollate under anaerobic conditions. Anaerobic CDC agar (formulated by the Center for Disease Control and Prevention) was employed as a culture medium and the microorganisms were identified using the API system. The microorganisms were subjected to antibiograms with three different antibiotics. Twenty-six microorganisms were identified, the most common genus was Enterococcus (26.8%), Streptococcus (19.22%), Aerococcus (19.1%), and Clostridium (11.4%). 48% of them were susceptible to amoxicillin, with 28% of resistance. For clavulanic acid/amoxicillin, the susceptibility occurred in 32%, with 28% of resistance; and for clindamycin, the susceptibility was present in 40%, with 52% of resistance. The most frequently detected associated microorganism for secondary infections was genus Enterococcus, which exhibited high resistance to the studied antibiotics.
Assuntos
Cavidade Pulpar , Periodontite Periapical , Amoxicilina , Antibacterianos/farmacologia , Humanos , Periodontite Periapical/tratamento farmacológico , Tratamento do Canal RadicularRESUMO
The need for effective candidates as cytotoxic drugs that at the same time challenge cancer multidrug resistance encouraged a search for these in plants of central Argentina. Bioassay-guided fractionation of the cytotoxic extract from Dimerostemma aspilioides led to the isolation of the germacranolide tomenphantin A (1), along with three new analogues (2-4). These efficiently inhibited the proliferation of the leukemia cell lines K562 and CCRF-CEM and their resistant variants, Lucena 1 and CEM/ADR5000, respectively, with IC50 values ranging from 0.40 to 7.7 µM. The structures and relative configurations of compounds 1-4 were elucidated by analysis of the spectroscopic data, in particular NMR spectroscopy. The most active among these was compound 1 (IC50 = 0.40-5.1 µM), and, therefore, this was selected as a model for a mechanistic study, which revealed that its antiproliferative effect was mediated by cell cycle arrest in the G2/M phase followed by apoptosis. The activity of compound 1 was selective, given the absence of cytotoxicity toward peripheral blood mononuclear cells. The results show the potential of these compounds, and in particular of compound 1, as leads for the development of drug candidates to fight sensitive and resistant leukemia cells.
Assuntos
Antineoplásicos Fitogênicos/farmacologia , Lactonas/farmacologia , Sesquiterpenos de Germacrano/química , Sesquiterpenos de Germacrano/farmacologia , Antineoplásicos Fitogênicos/química , Apoptose/efeitos dos fármacos , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Núcleo Celular/efeitos dos fármacos , Núcleo Celular/ultraestrutura , Proliferação de Células/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Lactonas/química , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Monócitos/efeitos dos fármacos , Componentes Aéreos da Planta/química , Extratos Vegetais/químicaRESUMO
Bioassay-guided fractionation of an ethanolic extract of the aerial parts of Dolichandra cynanchoides Cham. (Bignoniaceae) led to the isolation of a natural wax with anti-insect activity against Spodoptera frugiperda (Noctuidae) and Epilachna paenulata (Coleptera). The compound was identified spectroscopically as an ester of a C27 fatty acid and a C25 alcohol, pentacosyl heptacosanoate (1). The effective doses of 1 for 50% feeding inhibition (ED50) of S. frugiperda and E. paenulata were 0.82 and 8.53 µg/cm², respectively, in a choice test, while azadirachtin showed ED50 of 0.10 and 0.59 µg/cm², respectively. In a no-choice test, both insects refused to feed on leaves treated with 1 at doses of 0.1 µg/cm² or greater inhibiting larval growth and dramatically reducing survival. The lethal doses 50 (LD50) of 1 were 0.39 and 0.68 µg/cm² for S. frugiperda and E. paenulata, respectively. These results indicate that 1 has potential for development as botanical insecticides. Similar esters might be obtainable in large quantities as many edible crops produce wax esters that are discarded during food processing. Research on these materials could lead to the detection of similar waxes with insecticidal activity.
Assuntos
Bignoniaceae/química , Inseticidas/isolamento & purificação , Componentes Aéreos da Planta/química , Ceras/isolamento & purificação , Animais , Besouros/efeitos dos fármacos , Inseticidas/química , Inseticidas/farmacologia , Larva/efeitos dos fármacos , Dose Letal Mediana , Estrutura Molecular , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Spodoptera/efeitos dos fármacos , Ceras/química , Ceras/farmacologiaRESUMO
The enzyme 4-hydroxyphenylpyruvate dioxygenase catalyzes the second step in the tyrosine degradation pathway. In mammals, this enzyme is the molecular target of drugs used for the treatment of metabolic disorders associated with defects in the tyrosine catabolism, mainly the fatal hereditary disease tyrosinemia type 1. This study evaluated the inhibitory effect of 91 extracts on 4-hydroxyphenylpyruvate dioxygenase from mostly native plants from central Argentina. Flourensia oolepis ethanol extract showed itself to be the most effective, and bioguided fractionation yielded pinocembrin (1) as its active principle. This flavanone, with an IC50 value of 73.1 µM and a KI of 13.7 µM, behaved as a reversible inhibitor of the enzyme and as a noncompetitive inhibitor. Molecular modeling studies confirmed the inhibitory potency of 1 and explained its activity by means of in silico determination of its binding mode in comparison to inhibitors of known activity, cocrystallized with 4-hydroxyphenylpyruvate dioxygenase. The main structural determinants that confer its potency are discussed. Analysis of the binding mode of the flavanone 1 with 4-hydroxyphenylpyruvate dioxygenase revealed the basis of the noncompetitive reversible mechanism of inhibition at the molecular level, which seems to be a common feature in this ubiquitous family of natural compounds. The resulting information may establish the basis for obtaining novel 4-hydroxyphenylpyruvate dioxygenase inhibitors for the treatment of tyrosinemia type 1 and other disorders associated with tyrosinase catabolism.
Assuntos
4-Hidroxifenilpiruvato Dioxigenase/antagonistas & inibidores , Asteraceae/química , Inibidores Enzimáticos/farmacologia , Flavanonas/farmacologia , Animais , Argentina , Inibidores Enzimáticos/isolamento & purificação , Flavanonas/química , Flavanonas/isolamento & purificação , Modelos Moleculares , Estrutura Molecular , SuínosRESUMO
The aim of this study was to isolate the active principles of Flourensia oolepis S.F.Blake (Asteraceae), which completely inhibited the germination of Raphanus sativus seeds at 10â mg/ml. Flavanone pinocembrin and sesquiterpene ilicol, were isolated by bioassay-guided fractionation. They were active both against monocot and dicot seeds. Pinocembrin was the most active compound, with an IC50 (germination) value of 0.24, 3.40, 3.28, and 3.55â mM against Panicum miliaceum, Avena sativa, Lactuca sativa, and R. sativus, respectively; ilicol, however, exhibited IC50 (germination) values of 0.67, 2.73, 5.25, and 9.66â mM for the same species, respectively. Pinocembrin and ilicol inhibited root growth and showed IC50 (root growth) values of 0.199, 14.68, 8.05, 7.69â mM, and 1.22, 2.90, 7.35, 8.07â mM, against P. miliaceum, A. sativa, L. sativa, and R. sativus, respectively. Pinocembrin and ilicol reduced Allium cepa cell division without chromosome aberrations.
Assuntos
Asteraceae/química , Asteraceae/metabolismo , Flavanonas/química , Extratos Vegetais/toxicidade , Sesquiterpenos/química , Sesquiterpenos/toxicidade , Allium/crescimento & desenvolvimento , Flavanonas/isolamento & purificação , Flavanonas/farmacologia , Flavanonas/toxicidade , Germinação/efeitos dos fármacos , Mitose/efeitos dos fármacos , Componentes Aéreos da Planta/química , Componentes Aéreos da Planta/metabolismo , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/crescimento & desenvolvimento , Raphanus/crescimento & desenvolvimento , Sementes/crescimento & desenvolvimento , Sesquiterpenos/isolamento & purificação , Sesquiterpenos/farmacologiaRESUMO
INTRODUCTION: Autoimmune encephalitis represents a group of immune-mediated neurological disorders. At present, the description of the chronic cognitive sequela is scarce. The objective of this study was to characterize the cognitive after effects of different types of autoimmune encephalitis in a cohort from a single center in Argentina. METHODS: Prospective, observational, cross-sectional study of patients under follow-up at a hospital in Buenos Aires city, with a diagnosis of probable and definitive immune-mediated encephalitis. Epidemiological, clinical, paraclinical and treatment related variables were evaluated. Cognitive sequela was determined through a neurocognitive evaluation performed at least a year after the clinical presentation. RESULTS: Fifteen patients were included. All had diminished results in at least one test. Memory was the most affected domain. Patients who were under immunosuppressive treatment at the time of evaluation presented lower results in serial learning (mean -2.94; standard deviation 1.54) versus those who weren't under treatment (mean -1.18; standard deviation 1.40; p = 0.05). The same pattern was observed on the recognition test of treatment group (mean -10.34; standard deviation 8.02) versus treatment-free group (mean -1.39; standard deviation 2.21; p =0.003). Patients with status epilepticus had poorer results in the recognition test (mean -7.2; standard deviation 7.91) compared to those without it (mean -1.47; standard deviation 2.34; p = 0.05). CONCLUSION: Our results show that, despite the monophasic course of this disease, all patients had persistent cognitive damage beyond the year of onset. Larger prospective studies are required to confirm our findings.
Introducción: Las encefalitis inmunomediadas son un desorden neurológico de origen autoinmune. Actualmente es escasa la descripción de las secuelas cognitivas crónicas. El objetivo del presente trabajo fue caracterizar la secuela cognitiva de diferentes tipos de encefalitis inmunomediadas en una cohorte de un centro único de Argentina. Métodos: Estudio prospectivo, observacional, transversal, de pacientes en seguimiento en un hospital de la Ciudad de Buenos Aires, con diagnóstico de encefalitis inmunomediada probable y definitiva. Se evaluaron variables epidemiológicas, clínicas, paraclínicas y tratamiento. Se determinó la secuela cognitiva a través de una evaluación neurocognitiva realizada a partir del año de la presentación clínica. Resultados: Fueron incluidos 15 pacientes, todos con resultado disminuido en al menos un test. La memoria fue el dominio más afectado. Aquellos que se encontraban bajo tratamiento inmunosupresor al momento de evaluarse presentaron menores resultados en el aprendizaje seriado (media -2.94; desvío estándar 1.54) versus los que se encontraban sin tratamiento (media -1.18; desvío estándar 1.40; p = 0.05) y en la prueba de reconocimiento (media -10.34; desvío estándar 8.02) versus sin tratamiento (media -1.39; desvío estándar 2.21; p = 0.003). Los pacientes con estatus epiléptico tuvieron resultados deficitarios en la prueba de reconocimiento (media -7.2; desvío estándar 7.91) en comparación a los que no lo tenían (media -1.47; desvío estándar 2.34; p = 0.05). Conclusión: Nuestros resultados demuestran que, a pesar del curso monofásico de la enfermedad, todos los pacientes presentan daño cognitivo persistente más allá del año del inicio del cuadro. Estudios prospectivos de mayor envergadura serían necesarios para confirmar nuestros hallazgos.
Assuntos
Encefalite Antirreceptor de N-Metil-D-Aspartato , Doenças Autoimunes do Sistema Nervoso , Encefalite , Humanos , Argentina/epidemiologia , Cognição , Estudos Transversais , Progressão da Doença , Estudos ProspectivosRESUMO
Constitutive activation of the JAK/STAT pathway is a common phenomenon in classic Hodgkin lymphoma (cHL). The clinical potential of anti-JAK/STAT therapy is being explored in early-stage clinical trials. Notwithstanding, very little information is available about the complex biological consequences of this blockade. Here, we investigated the effects of JAK/STAT pharmacological inhibition on cHL cell models using ruxolitinib, a JAK 1/2 inhibitor that induces apoptosis by concentration- and time-dependent mechanisms. An unbiased whole-transcriptome approach identified expression of the anti-GCSF receptor (CSF3R) as a potential surrogate biomarker of JAK/STAT overactivation. In addition, longitudinal gene expression analyses provided further mechanistic information about pertinent biological pathways involved, including 37 gene pathways distributed in 3 main clusters: cluster 1 was characterized by upregulation of the G2/M checkpoint and major histocompatibility complex-related clusters; 2 additional clusters (2 and 3) showed a progressive downregulation of the tumor-promoting inflammation signatures: JAK/STAT and interleukin 1 (IL-1)/IL-4/IL-13/IL-17. Together, our results confirm the therapeutic potential of JAK/STAT inhibitors in cHL, identify CSF3R as a new biomarker, and provide supporting genetic data and mechanistic understanding.
Assuntos
Doença de Hodgkin , Células de Reed-Sternberg , Humanos , Transdução de Sinais , Janus Quinases , Fatores de Transcrição STAT/metabolismo , Doença de Hodgkin/genética , FenótipoRESUMO
To aid the pharmaceutical and cosmetic industry in the development of alternatives to prevent melanin-related hyperpigmentation disorders, the plant Dalea elegans was submitted to fractionation with the aim of obtaining its anti-tyrosinase principle. Bioguided fractionation of D. elegans led to the isolation of 5,2',4'-trihydroxy-2â³,2â³-dimethylchromene-(6,7:5â³,6â³)-flavanone (1) as the active compound. This novel flavanone, named as dalenin, showed notable activity at inhibiting tyrosinase using l-tyrosine or l-DOPA as substrates with IC(50) values of 0.26 and 18.61 µM, respectively. This meant that the flavanone was 52 and 495 times more effective as a monophenolase inhibitor than hydroquinone and kojic acid, respectively. With l-DOPA as a substrate, compound 1 showed itself 59 times more effective at inhibiting the enzyme than hydroquinone and showed the same level of effectiveness as that of kojic acid. It was found that the flavanone behaved as a reversible inhibitor of the enzyme and that it was a mixed-I type or a non-competitive inhibitor with l-tyrosine or l-DOPA as substrates, respectively. Molecular modeling studies were conducted confirming the inhibitory potency of dalenin and showing that the 2',4'-dihydroxy substituents are important for the interaction with the enzyme. The results suggest that compound 1 has great potential to be further developed as a pharmaceutical and cosmetic agent for use in dermatological disorders associated with melanin.
Assuntos
Inibidores Enzimáticos/química , Fabaceae/química , Flavanonas/química , Monofenol Mono-Oxigenase/antagonistas & inibidores , Agaricales/enzimologia , Sítios de Ligação , Simulação por Computador , Inibidores Enzimáticos/isolamento & purificação , Inibidores Enzimáticos/farmacologia , Flavanonas/isolamento & purificação , Flavanonas/farmacologia , Cinética , Monofenol Mono-Oxigenase/metabolismo , Terpenos/químicaRESUMO
The great increase in bacterial infections is fueling interest in the search for antibacterial products of plant origin. Extracts obtained from 51 native and naturalized plants from central Argentina were therefore evaluated for their IN VITRO inhibitory activity on pathogenic bacteria with the aim of selecting the most active ones as new sources of effective antibiotics. The susceptibility of reference and clinical strains of Enterococcus faecalis, Escherichia coli, Proteus mirabilis, Pseudomonas aeruginosa, Salmonella enterica serovar Enteritidis, and Staphylococcus aureus was determined. Extracts from Achyrocline satureioides, Flourensia oolepis, Lepechinia floribunda, and Lithrea molleoides were the most potent, with MIC and MBC values ranging from 0.006 to 2 and 0.012 to 10 mg/mL, respectively, on both gram-positive and negative bacteria. The antibacterial activity-guided isolation of A. satureioides ethanol extract showed 23-methyl-6-O-desmethylauricepyrone (1) to be the most active compound. This compound showed inhibitory effects against gram-positive bacteria with MIC and MBC values of 0.002 and 0.008 mg/mL, respectively, while on gram-negative strains, the MIC and MBC were 0.062-0.250 and 0.062-0.500 mg/mL, respectively. The strong antibacterial activity shown by the four plant extracts or the compound isolated from A. satureioides suggests that they could become part of the arsenal of antibacterial drugs currently used.
Assuntos
Achyrocline/química , Antibacterianos/farmacologia , Bactérias Gram-Positivas/efeitos dos fármacos , Pironas/farmacologia , Antibacterianos/química , Antibacterianos/isolamento & purificação , Argentina , Testes de Sensibilidade Microbiana , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Plantas/química , Pironas/química , Pironas/isolamento & purificaçãoRESUMO
Extracts of indigenous plants from South America have shown a broad spectrum of bioactivities. No-contaminant and natural substances have recently resurged as control treatment options for varroosis in honey bee colonies from Argentina. The aim of this work was to evaluate the biological activity of botanical extracts from Baccharis flabellata and Minthostachys verticillata on Varroa destructor and Apis mellifera. The acaricidal and insecticidal activities were assessed by the spraying application method. Both ethanolic extracts showed high levels of toxicity against the mites and were harmless to their host, A. mellifera. During the attractive-repellent test, the olfactory stimulus evoked for the extract from B. flabellata resulted as a repellent for mites. The aromatic stimulus of these extracts would be strong enough to cause disturbance on the behavior of V. destructor. Thus, the repellent effect of these substances plus the toxicity on mites postulate these botanical extracts like promising natural compound to be incorporated for the control of varroosis.
Assuntos
Acaricidas/farmacologia , Baccharis/química , Repelentes de Insetos/farmacologia , Lamiaceae/química , Extratos Vegetais/farmacologia , Varroidae/efeitos dos fármacos , Acaricidas/isolamento & purificação , Acaricidas/toxicidade , Animais , Argentina , Abelhas/efeitos dos fármacos , Feminino , Repelentes de Insetos/isolamento & purificação , Repelentes de Insetos/toxicidade , Extratos Vegetais/isolamento & purificação , Extratos Vegetais/toxicidade , Análise de SobrevidaRESUMO
Overexpression of P-glycoprotein (P-gp), which is linked to multidrug resistance (MDR), is one of the underlying obstacles to the success of chemotherapy as it reduces the efficacy of anticancer drugs and the side effects of these increase as a result of any increased dose to achieve the therapeutic effect. To identify agents with P-gp inhibitory properties, ethanol extracts from 80 plants were screened for their ability to increase intracellular doxorubicin-associated fluorescence, and the extract of Ligaria cuneifolia was found to be the most effective. Its bioassay-guided isolation yielded the pentacyclic triterpene betulin as active agent. This efficiently inhibited P-gp mediated efflux, as demonstrated by the enhancement of the intracellular accumulation of doxorubicin and rhodamine 123 from 1.56 µM in the P-gp overexpressing MDR leukemia cell, Lucena 1. Betulin was also able to render Lucena 1 sensitive to Dox from 0.39 µM. The docking studies revealed that betulin tightly binds to a key region of the TMDs, with a binding mode overlapping one main site of doxorubicin and, more interestingly, emulating the same contacts as tariquidar, as revealed by the per-residue energetic analysis from molecular dynamics simulations. MTT assay using peripheral blood mononuclear cells and hemolysis assay showed that betulin is devoid of toxicity. These findings provide important evidence that betulin may be a safe and promising entity to be further investigated to develop agents able to overcome P-gp-mediated MDR, resulting in a more effective and less toxic chemotherapy.
Assuntos
Subfamília B de Transportador de Cassetes de Ligação de ATP/metabolismo , Leucemia/tratamento farmacológico , Loranthaceae/química , Extratos Vegetais/farmacologia , Triterpenos/farmacologia , Subfamília B de Transportador de Cassetes de Ligação de ATP/genética , Antibióticos Antineoplásicos/metabolismo , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/farmacologia , Linhagem Celular Tumoral , Doxorrubicina/metabolismo , Resistencia a Medicamentos Antineoplásicos , Corantes Fluorescentes/metabolismo , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Estrutura Molecular , Extratos Vegetais/química , Rodamina 123/metabolismo , Triterpenos/químicaRESUMO
We examined the effects of the flavonoids pinocembrin and quercetin on the feeding behavior, survival, and development of the Cucurbitaceae pest Epilachna paenulata (Coleoptera: Coccinellidae). In no-choice experiments, 48 hr-consumption of Cucurbita maxima Duch. leaves treated with pinocembrin at 1, 5, and 50 microg/cm(2) was less than one third of that for leaves treated with 0.1 microg/cm(2) of pinocembrin or untreated leaves. Larvae stopped feeding after 9 days of high doses of pinocembrin (5 and 50 microg/cm(2)), and larval weight and survival were negatively affected by pinocembrin at 1-50 microg/cm(2). Delayed mortality in comparison to food-deprived larvae suggests that the mechanism of action for pinocembrin is chronic intoxication, rather than simple starvation from antifeedant effects. In contrast, leaf consumption and larval weight were not significantly affected by quercetin (at 0.1, 1, 5, and 50 microg/cm(2)) while mortality rates were only slightly increased. The response of E. paenulata larvae in a choice-test to combinations of pinocembrin at antifeedant doses (5 and 50 microg/cm(2)) and quercetin at phagostimulant doses (0.01 and 0.1 microg/cm(2)) indicated that the feeding deterrent activity of the former completely overshadowed the stimulant activity of the latter. These results demonstrate the different responses of one insect species to two widely distributed plant flavonoids. Pinocembrin strongly affected survival of E. paenulata while quercetin had only a weak effect without major consequences on the insect life-cycle.
Assuntos
Besouros/efeitos dos fármacos , Flavanonas/farmacologia , Quercetina/farmacologia , Animais , Peso Corporal/efeitos dos fármacos , Besouros/crescimento & desenvolvimento , Besouros/fisiologia , Relação Dose-Resposta a Droga , Comportamento Alimentar/efeitos dos fármacos , Flavanonas/toxicidade , Larva/efeitos dos fármacos , Larva/crescimento & desenvolvimento , Larva/fisiologia , Dose Letal Mediana , Análise de SobrevidaRESUMO
Plants are a potential source of bioactive compounds and offer a promising strategy for the treatment of neurological disorders such as Alzheimer's disease. The inhibitory effect of 73 native and naturalized plants collected from the central region of Argentina on acetylcholinesterase (AChE) was tested using microplate and TLC assays after solvent fractionation of complete ethanol extracts obtained from the plants. Organic fractions obtained from extracts of Achyrocline tomentosa (Asteraceae), Eupatorium viscidum (Asteraceae), Ruprechtia apetala (Polygonaceae) Trichocline reptans (Asteraceae) and Zanthoxylum coco (Rutaceae) presented strong inhibition of AChE (higher than 80%) at 1 mg/mL, with R. apetala and T. reptans being the most potent, showing complete inhibition of the enzyme. Their IC(50) values were 0.0779 and 0.1118 mg/mL, respectively. Aqueous fractions did not show any inhibitory activity on the enzyme. These results suggest that the most effective extracts deserve further investigation with the aim of obtaining new molecules for the treatment of neurodegenerative disorders.
Assuntos
Asteraceae/química , Inibidores da Colinesterase/farmacologia , Extratos Vegetais/farmacologia , Polygonaceae/química , Rutaceae/química , Argentina , Inibidores da Colinesterase/isolamento & purificação , Concentração Inibidora 50RESUMO
Monomers 4,7-dibromo-2H-benzo[d]1,2,3-triazole (m1) and 4,7-(bis(4-bromophenyl)ethynyl)-2H-benzo[d]1,2,3-triazole (m2) have been synthesized in good yields using different procedures. Monomers m1 and m2 have been employed for building new copolymers of fluorene derivatives by a Suzuki reaction under microwave irradiation using the same conditions. In each case different chain lengths have been achieved, while m1 gives rise to polymers for m2 oligomers have been obtained (with a number of monomer units lower than 7). Special interest has been paid to their photophysical properties due to excited state properties of these D-A units alternates, which have been investigated by density functional theory (DFT) calculations using two methods: (i) An oligomer approach and (ii) by periodic boundary conditions (PBC). It is highly remarkable the tunability of the photophysical properties as a function of the different monomer functionalization derived from 2H-benzo[d]1,2,3-triazole units. In fact, a strong modulation of the absorption and emission properties have been found by functionalizing the nitrogen N-2 of the benzotriazole units or by elongation of the π-conjugated core with the introduction of alkynylphenyl groups. Furthermore, the charge transport properties of these newly synthesized macromolecules have been approached by their implementation in organic field-effect transistors (OFETs) in order to assess their potential as active materials in organic optoelectronics.
RESUMO
The insecticidal activity of nine essential oils (EOs) against the house fly (Musca domestica) was evaluated by placing flies in a screw-cap glass jar holding a piece of EO-treated cotton yarn. The dose necessary to kill 50% of flies (LC(50)) in 30 min was determined at 26 +/- 1 degrees C. The EOs showed LC(50) values ranging from 0.5 to 46.9 mg/dm(3). The EO from Minthostachys verticillata was the most potent insecticide (LC(50) = 0.5 mg/dm(3)) followed by EOs from Hedeoma multiflora (LC(50) = 1.3 mg/dm(3)) and Artemisia annua (LC(50) = 6.5 mg/dm(3)). The compositions of the nine EOs, obtained by hydrodistillation of medicinal herbs, were analyzed by gas chromatography/mass spectroscopy. These analyses showed that (4R)(+)-pulegone (69.70%), menthone (12.17%), and limonene (2.75%) were the principal components of M. verticillata EO. (4R)(+)-pulegone was also the main constituent (52.80%) of H. multiflora, while artemisia ketone (22.36%) and 1,8-cineole (16.67%) were the major constituents of A. annua EO. The terpene (4R)(+)-pulegone showed a lower toxicity (LC(50) = 1.7 mg/dm(3)) than M. verticillata or H. multiflora EOs. Dimethyl 2,2-dichlorovinyl phosphate, selected as a positive control, showed an LC(50) of 0.5 mg/dm(3). EOs from M. verticillata and H. multiflora show promise as natural insecticides against houseflies.
Assuntos
Artemisia annua/química , Moscas Domésticas/efeitos dos fármacos , Inseticidas/farmacologia , Lamiaceae/química , Óleos Voláteis/farmacologia , Plantas Medicinais/química , Animais , Argentina , Cromatografia Gasosa-Espectrometria de Massas , Inseticidas/isolamento & purificação , Dose Letal Mediana , Óleos Voláteis/química , Óleos Voláteis/isolamento & purificação , Análise de SobrevidaRESUMO
The compositions of 12 essential oils (EOs) obtained by hydrodistillation of edible fruits and herbs were analyzed by gas chromatography/mass spectroscopy (GC/MS). The insecticidal activity of each oil against the house fly Musca domestica was evaluated by placing flies in a glass jar with a screw cap that held a piece of EO-treated cotton yarn. The dose necessary to kill 50% of flies (LC(50)) in 30 min was determined at 26 +/- 1 degrees C. Twelve EOs and 17 individual terpenes were assayed against M. domestica, showing LC(50) values ranging from 3.9 to 85.2 and from 3.3 to >100 mg/dm(3), respectively. EO from Citrus sinensis was the most potent insecticide (LC(50 )= 3.9 mg/dm(3)), followed by EOs from C. aurantium (LC(50 )= 4.8 mg/dm(3)) and Eucalyptus cinerea (LC(50 )= 5.5 mg/dm(3)). According to GC/MS analysis, limonene (92.47%), linalool (1.43%), and b-myrcene (0.88%) were the principal components of C. sinensis EO. Limonene was also the principal constituent (94.07%) of C. aurantium, while 1,8-cineole (56.86%) was the major constituent of E. cinerea EO. 1,8-Cineole was most active against M. domestica (LC(50 )= 3.3 mg/dm(3)), while (4R)(+)-limonene, was moderately active (LC(50 )= 6.2 mg/dm(3)). Dimethyl 2,2-dichlorovinyl phosphate (DDVP) selected as a positive control, showed an LC(50) of 0.5 mg/dm(3). EOs from C. sinensis, C. aurantium, and E. cinerea show promise as natural insecticides against houseflies.
Assuntos
Moscas Domésticas/efeitos dos fármacos , Inseticidas/farmacologia , Óleos Voláteis , Óleos de Plantas , Terpenos , Animais , Feminino , Humanos , Óleos Voláteis/química , Óleos Voláteis/farmacologia , Óleos de Plantas/química , Óleos de Plantas/farmacologia , Terpenos/química , Terpenos/farmacologiaRESUMO
Un programa de ciencia, tecnología e innovación es un conjunto de actividades organizadas en proyectos que se relacionan entre sí, cuyo objetivo es resolver un problema identificado según las prioridades y dirigido a lograr resultados de impactos específicos. En la provincia Santiago de Cuba está en acción, desde el año 2020, el Programa Territorial "Desarrollo de productos y servicios de salud", que ha ejecutado 12 proyectos de investigación. En el presente artículo se identifican sus resultados científico-técnicos y, además, se plantea que estos responden a prioridades sectoriales y territoriales y se encuentran en correspondencia con las políticas del sector sanitario y de la educación superior en Cuba. Su introducción contribuye a resolver las problemáticas de salud en el territorio mediante la aplicación de la ciencia y la innovación tecnológica para el diagnóstico, el tratamiento y la rehabilitación de pobladores con enfermedades.
A science, technology and innovation program is a group of activities organized in projects that are related to each other, which objective is to solve a problem identified according to the priorities and directed to achieve results of specific impacts. In Santiago de Cuba province the Territorial Program "Development of products and health services" is in action since 2020, which has implemented 12 investigation projects. In this work the scientific-technical results are identified; also, it is considered that they respond to sectoral and territorial priorities and are in correspondence with the policy of the health sector and higher education in Cuba. Their introduction contributes to solve the health problems in the territory by means of the implementation of science and technological innovation for the diagnosis, treatment and rehabilitation of persons with diseases.
RESUMO
Introducción: La mortalidad infantil es un fenómeno sanitario relacionado directamente con las condiciones de vida deletéreas, tanto del hogar del infante como de factores socioeconómicos e higiénico-sanitarios adversos. Objetivo: Caracterizar las desigualdades de la mortalidad infantil, según condiciones diferenciales de vida en dos distritos poblacionales de Santiago de Cuba. Métodos: Se llevó a cabo un estudio descriptivo, de tipo ecológico exploratorio, en el municipio Santiago de Cuba, en el trienio 1995-1997. Las unidades de análisis estuvieron constituidas por las áreas de salud enmarcadas en dos distritos poblacionales de la ciudad. Resultados: Se estratificaron ambos distritos poblacionales, según sus condiciones de vida, en asentamientos con condiciones de vida menos desfavorables y más desfavorables. Se estimó mayor mortalidad infantil en el asentamiento con condiciones de vida más desfavorables (8,7 fallecidos por 1000 nacidos vivos), donde predominaron como causas clínicas de muerte las asfixias, la anoxia e hipoxias y causas clínicas reducibles por buena atención en el parto. Conclusiones: Se identificó un perfil diferencial de mortalidad infantil, según las condiciones de vida, al interior de los asentamientos poblacionales de los distritos urbanos de Santiago de Cuba. Los riesgos distintivos de muerte infantil fueron a expensas del componente neonatal, en lo fundamental por causas clínicas reducibles por buena atención en el parto.
Introduction: Infant mortality is a health phenomenon directly related to the deleterious living conditions of both the infant's home and adverse socioeconomic and sanitary factors. Objective: To characterize inequalities in infant mortality according to differential living conditions in two populations districts of Santiago de Cuba. Methods: A descriptive, exploratory ecological study was carried out in the municipality of Santiago de Cuba in 1995-1997. The units of analysis were constituted by the areas framed in two populations districts of the city. Results: Bothe population districts were stratified, according to their living conditions, in settlements with less unfavorable and more unfavorable living conditions. Higher infant mortality was estimated in the settlement with more unfavorable living conditions (8.7 deaths per 1000 live births), where asphyxia, anoxia and hypoxia predominated as clinical causes of death and clinical causes reducible for good care at birth. Conclusions: A differential profile of infant mortality, according to living conditions, was identified within the population settlements of the urban districts of Santiago de Cuba. The distinctive risks of infant death were at the expense of the neonatal component, mainly for clinical causes reducible by good care at birth.