30 research outputs found
Atividade antimicrobiana de vários quimiotipos de Lippia graveolens contra Aeromonas hydrophila isolada de Oreochromis niloticus
[Objective] This study aimed to evaluate the antimicrobial efficacy of essential oil (EO) from diverse chemotypes of Lippia graveolens against oxytetracycline-resistant Aeromonas hydrophila, which primarily affects the tilapia aquaculture (O. niloticus) in Guatemala. [Methodology] L. graveolens were collected in three departments in Guatemala. The EO was obtained by hydrodistillation and characterized using gas chromatography and mass spectrometry (GC/MS). Subsequently, an antimicrobial assay was conducted using disk and dilution susceptibility tests and evaluation of synergistic interactions among the chemotypes. Each test was performed in triplicate. [Results] The analysis revealed the presence of twenty-seven compounds in the EO obtained from the chemotypes, with the main class being monoterpenes. The major constituents identified were cis-Dihydro-β-terpineol (8.84%) in chemotype I, carvacrol (51.82%) in chemotype II, and thymol (79.62%) in chemotype III. All EO chemotypes of L. graveolens demonstrated the ability to inhibit the A. hydrophila growth. Thymol chemotype exhibited the strongest inhibitory effect against bacterial growth, with a minimum inhibitory concentration (MIC) of 92.4 µg/mL and a minimum bactericidal concentration (MBC) of 184.8 µg/mL. Furthermore, the results suggest that there is no synergistic or additive effect when combining different chemotypes of L. graveolens. [Conclusions] This is the first report of L. graveolens chemotypes exhibiting antimicrobial activity against oxytetracycline-resistant A. hydrophila. The findings suggest that the chemotype thymol could be a potential treatment for infections in the tilapia aquaculture in Guatemala.[Objetivo] El objetivo de este estudio fue evaluar la eficiencia antimicrobiana del aceite esencial de diversos quimiotipos de Lippia graveolens contra la cepa Aeromonas hydrophila resistente a la oxitetraciclina, la cual afecta principalmente a la acuicultura de tilapia (O. niloticus) en Guatemala. [Metodología] L. graveolens se colectó en tres departamentos de Guatemala, los aceites esenciales (AE) se obtuvieron mediante hidrodestilación y se caracterizaron mediante cromatografía de gases y espectrometría de masas (GC/MS). Posteriormente, se realizó un ensayo antimicrobiano utilizando pruebas de susceptibilidad en disco y dilución, y se evaluaron las interacciones sinérgicas entre los diferentes quimiotipos. Cada prueba se repitió tres veces. [Resultados] El análisis evidenció la presencia de veintisiete compuestos en los AE obtenidos de los quimiotipos, siendo los monoterpenos la clase principal. Los principales constituyentes identificados fueron cis-dihidro-β-terpineol (8.84 %) en el quimiotipo I, carvacrol (51.82 %) en el quimiotipo II y timol (79.62 %) en el quimiotipo III. Todos los AE de los diferentes quimiotipos de L. graveolens demostraron capacidad para inhibir el crecimiento de A. hydrophila. En particular, el quimiotipo timol obtuvo el efecto inhibitorio más fuerte contra el crecimiento bacteriano, con una concentración mínima inhibitoria (CMI) de 92.4 µg/mL y una concentración mínima bactericida (CMB) de 184.8 µg/mL. Los resultados sugieren que no existe un efecto sinérgico o aditivo al combinar los diferentes quimiotipos de L. graveolens. [Conclusiones] Este estudio constituye el primer reporte sobre la actividad antimicrobiana de los diferentes quimiotipos de L. graveolens contra A. hydrophila resistente a la oxitetraciclina. Los hallazgos sugieren que el quimiotipo timol podría ser un tratamiento potencial para las infecciones en la acuicultura de tilapia en Guatemala.[Objetivo] O objetivo deste estudo foi avaliar a eficiência antimicrobiana do óleo essencial de vários quimiotipos de Lippia graveolens contra a cepa Aeromonas hydrophila resistente à oxitetraciclina, que afeta principalmente a aquicultura de tilápia (O. niloticus) na Guatemala. [Metodologia] A L. graveolens foi coletada em três setores da Guatemala, os óleos essenciais (OE) foram obtidos por hidrodestilação e caracterizados por cromatografia a gás acoplada à espectrometria de massas (GC/MS). Posteriormente, foi realizado um ensaio antimicrobianos por meio de testes de suscetibilidade de disco e diluição, e foram avaliadas as interações sinérgicas entre os diferentes quimiotipos. Cada teste foi repetido três vezes. [Resultados] A análise revelou a presença de vinte e sete compostos nos OEs obtidos dos quimiotipos, sendo os monoterpenos a classe principal. Os principais constituintes identificados foram cis-di-hidro-β-terpineol (8,84%) no quimiotipo I, carvacrol (51,82%) no quimiotipo II e timol (79,62%) no quimiotipo III. Todos os OEs dos diferentes quimiotipos de L. graveolens mostraram a capacidade de inibir o crescimento de A. hydrophila. Em particular, o quimiotipo timol obteve o efeito inibitório mais forte contra o crescimento bacteriano, com uma concentração inibitória mínima (CIM) de 92,4 µg/mL e uma concentração bactericida mínima (CBM) de 184,8 µg/mL. Os resultados sugerem que não há efeito sinérgico ou aditivo ao combinar os diferentes quimiotipos de L. graveolens. [Conclusões] Este estudo é o primeiro relatório sobre a atividade antimicrobiana dos diferentes quimiotipos de L. graveolens contra A. hydrophila resistente à oxitetraciclina. Os resultados sugerem que o quimiotipo timol pode ser um tratamento em potencial para infecções na aquicultura de tilápia na Guatemala
Creación de un cibermedio sobre periodismo: "Académica_mente”
Depto. de Periodismo y Comunicación GlobalDepto. de Periodismo y Nuevos MediosFac. de Ciencias de la InformaciónFALSEsubmitte
Identification of 12 new susceptibility loci for different histotypes of epithelial ovarian cancer.
To identify common alleles associated with different histotypes of epithelial ovarian cancer (EOC), we pooled data from multiple genome-wide genotyping projects totaling 25,509 EOC cases and 40,941 controls. We identified nine new susceptibility loci for different EOC histotypes: six for serous EOC histotypes (3q28, 4q32.3, 8q21.11, 10q24.33, 18q11.2 and 22q12.1), two for mucinous EOC (3q22.3 and 9q31.1) and one for endometrioid EOC (5q12.3). We then performed meta-analysis on the results for high-grade serous ovarian cancer with the results from analysis of 31,448 BRCA1 and BRCA2 mutation carriers, including 3,887 mutation carriers with EOC. This identified three additional susceptibility loci at 2q13, 8q24.1 and 12q24.31. Integrated analyses of genes and regulatory biofeatures at each locus predicted candidate susceptibility genes, including OBFC1, a new candidate susceptibility gene for low-grade and borderline serous EOC
Albiglutide and cardiovascular outcomes in patients with type 2 diabetes and cardiovascular disease (Harmony Outcomes): a double-blind, randomised placebo-controlled trial
Background:
Glucagon-like peptide 1 receptor agonists differ in chemical structure, duration of action, and in their effects on clinical outcomes. The cardiovascular effects of once-weekly albiglutide in type 2 diabetes are unknown. We aimed to determine the safety and efficacy of albiglutide in preventing cardiovascular death, myocardial infarction, or stroke.
Methods:
We did a double-blind, randomised, placebo-controlled trial in 610 sites across 28 countries. We randomly assigned patients aged 40 years and older with type 2 diabetes and cardiovascular disease (at a 1:1 ratio) to groups that either received a subcutaneous injection of albiglutide (30–50 mg, based on glycaemic response and tolerability) or of a matched volume of placebo once a week, in addition to their standard care. Investigators used an interactive voice or web response system to obtain treatment assignment, and patients and all study investigators were masked to their treatment allocation. We hypothesised that albiglutide would be non-inferior to placebo for the primary outcome of the first occurrence of cardiovascular death, myocardial infarction, or stroke, which was assessed in the intention-to-treat population. If non-inferiority was confirmed by an upper limit of the 95% CI for a hazard ratio of less than 1·30, closed testing for superiority was prespecified. This study is registered with ClinicalTrials.gov, number NCT02465515.
Findings:
Patients were screened between July 1, 2015, and Nov 24, 2016. 10 793 patients were screened and 9463 participants were enrolled and randomly assigned to groups: 4731 patients were assigned to receive albiglutide and 4732 patients to receive placebo. On Nov 8, 2017, it was determined that 611 primary endpoints and a median follow-up of at least 1·5 years had accrued, and participants returned for a final visit and discontinuation from study treatment; the last patient visit was on March 12, 2018. These 9463 patients, the intention-to-treat population, were evaluated for a median duration of 1·6 years and were assessed for the primary outcome. The primary composite outcome occurred in 338 (7%) of 4731 patients at an incidence rate of 4·6 events per 100 person-years in the albiglutide group and in 428 (9%) of 4732 patients at an incidence rate of 5·9 events per 100 person-years in the placebo group (hazard ratio 0·78, 95% CI 0·68–0·90), which indicated that albiglutide was superior to placebo (p<0·0001 for non-inferiority; p=0·0006 for superiority). The incidence of acute pancreatitis (ten patients in the albiglutide group and seven patients in the placebo group), pancreatic cancer (six patients in the albiglutide group and five patients in the placebo group), medullary thyroid carcinoma (zero patients in both groups), and other serious adverse events did not differ between the two groups. There were three (<1%) deaths in the placebo group that were assessed by investigators, who were masked to study drug assignment, to be treatment-related and two (<1%) deaths in the albiglutide group.
Interpretation:
In patients with type 2 diabetes and cardiovascular disease, albiglutide was superior to placebo with respect to major adverse cardiovascular events. Evidence-based glucagon-like peptide 1 receptor agonists should therefore be considered as part of a comprehensive strategy to reduce the risk of cardiovascular events in patients with type 2 diabetes.
Funding:
GlaxoSmithKline
Multiancestry analysis of the HLA locus in Alzheimer’s and Parkinson’s diseases uncovers a shared adaptive immune response mediated by HLA-DRB1*04 subtypes
Across multiancestry groups, we analyzed Human Leukocyte Antigen (HLA) associations in over 176,000 individuals with Parkinson’s disease (PD) and Alzheimer’s disease (AD) versus controls. We demonstrate that the two diseases share the same protective association at the HLA locus. HLA-specific fine-mapping showed that hierarchical protective effects of HLA-DRB1*04 subtypes best accounted for the association, strongest with HLA-DRB1*04:04 and HLA-DRB1*04:07, and intermediary with HLA-DRB1*04:01 and HLA-DRB1*04:03. The same signal was associated with decreased neurofibrillary tangles in postmortem brains and was associated with reduced tau levels in cerebrospinal fluid and to a lower extent with increased Aβ42. Protective HLA-DRB1*04 subtypes strongly bound the aggregation-prone tau PHF6 sequence, however only when acetylated at a lysine (K311), a common posttranslational modification central to tau aggregation. An HLA-DRB1*04-mediated adaptive immune response decreases PD and AD risks, potentially by acting against tau, offering the possibility of therapeutic avenues
Patógenos bacterianos e sua resistência aos antimicrobianos nos cultivos de tilápia na Guatemala
Este estudio muestra el trabajo realizado durante el año 2018-2019, donde se identificaron los principales patógenos bacterianos que afectan los cultivos de la tilapia en Guatemala, al mismo tiempo se evaluó la resistencia a los antibióticos de mayor uso en la industria acuícola de esta zona. Se recolectaron peces con peso de 50 a 1 000 g, en diversos centros de producción. Por cada organismo se registró la signología macroscópica externa e interna más frecuente, posteriormente se aislaron muestras bacteriológicas de fluido sanguíneo, úlceras y otras áreas hemorrágicas, riñón anterior, bazo, meninges, hígado y corazón. Las bacterias patógenas aisladas fueron identificadas a nivel de especie, a través de pruebas bioquímicas. Finalmente se evaluó la susceptibilidad con los antibióticos: oxitetraciclina (40 μg), florfenicol (40 μg), enrofloxacina (40 μg) y fosfomicina (40 μg) por el método de difusión de disco. Los organismos evidenciaron, en su mayoría, ulceras cutáneas, áreas hiperémicas, melanización corporal, hígado pálido y friable, vasculitis en hígado, congestión y hemorragia intestinal. Se lograron aislar 16 cepas bacterianas patógenas para la tilapia, los géneros más frecuentes fueron: Aeromonas (70 %: 3 spp), seguido por Plesiomonas, Burkholderia, Pseudomonas, Shewanella y Streptococcus (6 %: 1 sp). Se observó que las cepas bacterianas aisladas mostraron resistencia hacia los antibióticos oxitetraciclina (25 %) y fosfomicina (25 %). Todas las cepas bacterianas aisladas evidenciaron sensibilidad a florfenicol y enrofloxacina. La determinación de los patógenos más frecuentes, así como su resistencia antimicrobiana en la industria acuícola, es el primer reporte que se genera para Guatemala.The aim of this study was to identify the main bacterial pathogens affecting tilapia aquaculture in Guatemala during 2018-2019 and evaluate their resistance to the most widely used antibiotics in the aquaculture industry of the area. Fish weighing between 50 and 1,000 g were collected from different production centers. The most frequent external and internal macroscopic signs were recorded for each organism. In addition, bacteriological samples of blood fluid, ulcers and other hemorrhagic areas, anterior kidney, spleen, meninges, liver, and heart were isolated. The isolated pathogenic bacteria were identified at the species level through biochemical tests. Finally, susceptibility was assessed with the following antibiotics oxytetracycline (40 μg), florfenicol (40 μg), enrofloxacin (40 μg), and fosfomycin (40 μg) by the disk diffusion method. The most common clinical signals were skin ulcers, hyperemic areas, body melanization, pale and soft liver, liver vasculitis, and intestinal congestion and bleeding. A total of 16 pathogenic bacteria strains were isolated from tilapia samples. The most frequent genera were Aeromonas (70%: 3 spp), followed by Plesiomonas, Burkholderia, Pseudomonas, Shewanella, and Streptococcus (6%; 1 sp). Isolated bacteria strains showed resistance to oxytetracycline (25%) and fosfomycin (25%) and sensitivity to florfenicol and enrofloxacin. This is the first report related to the most frequent bacterial pathogens and their antimicrobial resistance in tilapia culture in Guatemala.Este estudo mostra o trabalho realizado durante os anos 2018 e 2019, em que foram identificados os principais patógenos bacterianos que afetam os cultivos da tilápia na Guatemala e, conjuntamente, avaliada a resistência aos antibióticos mais usados na indústria aquícola desta zona. Foram coletados peixes com peso de 50 a 1000g, em diversos centros de produção. Por cada organismo, houve o registro dos sinais macroscópicos externos e internos mais frequente, posteriormente foram isoladas amostras bacteriológicas de: fluxo sanguíneo, úlceras e outras áreas hemorrágicas, rim anterior, baço, meninges, fígado e coração. As bactérias patógenas isoladas foram identificadas por espécie, através de provas bioquímica. Finalmente, a susceptibilidade foi avaliada com os antibióticos: oxitetraciclina (40 μg), florfenicol (40 μg), enrofloxacino (40 μg) e fosfomicina (40 μg) por meio do método de disco-difusão. Os organismos evidenciaram, em sua maioria, úlceras cutâneas, áreas hiperêmicas, melanização corporal, fígado pálido e friável, vasculites no fígado, congestão e hemorragia intestinal. Foi possível o isolamento de 16 cepas bacterianas patógenas para a tilápia, sendo os gêneros mais frequentes: Aeromonas (70 %: 3 spp.), seguido por Plesiomonas, Burkholderia, Pseudomonas, Shewanella e Streptococcus (6 %: 1 sp.). Observou-se que as cepas bacterianas isoladas mostraram resistência com relação aos antibióticos oxitetraciclina (25 %) e fosfomicina (25 %). Todas as cepas bacterianas isoladas mostraram sensibilidade ao florfenicol e ao enrofloxacino. A determinação dos patógenos mais frequentes, assim como sua resistência antimicrobiana na indústria aquícola é o primeiro relatório gerado para a Guatemala.Universidad Nacional, Costa RicaEscuela de Ciencias Biológica
Broad antiviral spectrum of glycyrrhizic acid for human and veterinary medicine: reality or fiction?
Background: Emerging virus infections provoke health problems in people and animals, which generate social, and economic issues worldwide. This has spurred the search for new pharmacological strategies to confront them. Summary: The purpose of this review is to draw the reader's attention to pharmacological evaluations of glycyrrhizic acid (GA) and its analogs on the broad range of viruses known in human and veterinary medicine. GA is the main water-soluble constituent extracted from the roots of plants from the genus Glycyrrhiza, commonly known as licorice root. It has long been used due to its broad spectrum of bioactivities, including anti-inflammatory, antiulcer, and antitumor properties. It has also been proposed as an antiviral agent. Medicines derived from GA are currently being used to combat acute and chronic hepatitis and herpes viruses. Key Messages: This review suggests that GA could be a new broad-spectrum antiviral due to its ability to inhibit DNA or RNA viruses both in vitro and in vivo. GA could be a potential drug for preventing and/or treating various viral diseases
Approaches in Polymeric Nanoparticles for Vaginal Drug Delivery: A Review of the State of the Art
The vagina is a region of administration with a high contact surface to obtain local or systemic effects. This anatomical area represents special interest for government health systems for different sexually transmitted infections. However, the chemical changes of the vagina, as well as its abundant mucus in continuous exchange, act as a barrier and a challenge for the development of new drugs. For these purposes, the development of new pharmaceutical forms based on nanoparticles has been shown to offer various advantages, such as bioadhesion, easy penetration of the mucosa, and controlled release, in addition to decreasing the adverse effects of conventional pharmaceutical forms. In order to obtain nanoparticles for vaginal administration, the use of polymers of natural and synthetic origin including biodegradable and non-biodegradable systems have gained great interest both in nanospheres and in nanocapsules. The main aim of this review is to provide an overview of the development of nanotechnology for vaginal drug release, analyzing the different compositions of polymeric nanoparticles, and emphasizing new trends in each of the sections presented. At the end of this review, a section analyzes the properties of the vehicles employed for the administration of nanoparticles and discusses how to take advantage of the properties that they offer. This review aims to be a reference guide for new formulators interested in the vaginal route
Nanosystems in Edible Coatings: A Novel Strategy for Food Preservation
Currently, nanotechnology represents an important tool and an efficient option for extending the shelf life of foods. Reducing particle size to nanometric scale gives materials distinct and improved properties compared to larger systems. For food applications, this technology allows the incorporation of hydrophilic and lipophilic substances with antimicrobial and antioxidant properties that can be released during storage periods to increase the shelf life of diverse products, including whole and fresh-cut fruits and vegetables, nuts, seeds, and cheese, among others. Edible coatings are usually prepared with natural polymers that are non-toxic, economical, and readily available. Nanosystems, in contrast, may also be prepared with biodegradable synthetic polymers, and liquid and solid lipids at room temperature. In this review, recent developments in the use of such nanosystems as nanoparticles, nanotubes, nanocomposites, and nanoemulsions, are discussed critically. The use of polymers as the support matrix for nanodispersions to form edible coatings for food preservation is also analyzed, but the central purpose of the article is to describe available information on nanosystems and their use in different food substrates to help formulators in their work