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1.
Med Vet Entomol ; 35(1): 97-105, 2021 03.
Artículo en Inglés | MEDLINE | ID: mdl-32827166

RESUMEN

Aedes albopictus (Diptera: Culicidae) distribution is bounded to a subtropical area in Argentina, while Aedes aegypti (Diptera: Culicidae) covers both temperate and subtropical regions. We assessed thermal and photoperiod conditions on dormancy status, development time and mortality for these species from subtropical Argentina. Short days (8 light : 16 dark) significantly increased larval development time for both species, an effect previously linked to diapause incidence. Aedes albopictus showed higher mortality than Ae. aegypti at 16 °C under long day treatments (16 light : 8 dark), which could indicate a lower tolerance to a sudden temperature decrease during the summer season. Aedes albopictus showed a slightly higher percentage of dormant eggs from females exposed to a short day, relative to previous research in Brazilian populations. Since we employed more hours of darkness, this could suggest a relationship between day-length and dormancy intensity. Interestingly, local Ae. aegypti presented dormancy similar to Ae. albopictus, in accordance with temperate populations. The minimum dormancy in Ae. albopictus would not be sufficient to extend its bounded distribution. We believe that these findings represent a novel contribution to current knowledge about the ecophysiology of Ae. albopictus and Ae. aegypti, two species with great epidemiological relevance in this subtropical region.


Asunto(s)
Aedes/fisiología , Diapausa de Insecto , Rasgos de la Historia de Vida , Fotoperiodo , Temperatura , Aedes/crecimiento & desarrollo , Animales , Argentina , Femenino , Larva/crecimiento & desarrollo , Larva/fisiología , Masculino , Pupa/crecimiento & desarrollo , Pupa/fisiología
2.
Anim Cogn ; 21(3): 433-439, 2018 05.
Artículo en Inglés | MEDLINE | ID: mdl-29488112

RESUMEN

Spatial perseveration has been documented for domestic animals such as mules, donkeys, horses and dogs. However, evidence for this spatial cognition behavior among other domestic species is scarce. Alpacas have been domesticated for at least 7000 years yet their cognitive ability has not been officially reported. The present article used an A-not-B detour task to study the spatial problem-solving abilities of alpacas (Vicugna pacos) and to identify the perseveration errors, which refers to a tendency to maintain a learned route, despite having another available path. The study tested 51 alpacas, which had to pass through a gap at one end of a barrier in order to reach a reward. After one, two, three or four repeats (A trials), the gap was moved to the opposite end of the barrier (B trials). In contrast to what has been found in other domestic animals tested with the same task, the present study did not find clear evidence of spatial perseveration. Individuals' performance in the subsequent B trials, following the change of gap location, suggests no error persistence in alpacas. Results suggest that alpacas are more flexible than other domestic animals tested with this same task, which has important implications in planning proper training for experimental designs or productive purposes. These results could contribute toward enhancing alpacas' welfare and our understanding of their cognitive abilities.


Asunto(s)
Camélidos del Nuevo Mundo/psicología , Percepción Espacial , Conducta Espacial , Animales , Cognición , Femenino , Locomoción , Masculino , Solución de Problemas
3.
J Fish Biol ; 92(2): 399-419, 2018 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-29235101

RESUMEN

Changes in the isotopic composition (δ13 C and δ15 N) in biofilm, macro-invertebrates and resident salmonids were used to characterize temporal dynamics of marine derived nutrients (MDNs) incorporation between stream reaches with and without MDN inputs. Five Atlantic rivers were chosen to represent contrasting MDN subsidies: four rivers with considerable numbers of anadromous fishes; one river with little MDN input. Rainbow smelt Osmerus mordax, alewife Alosa pseudoharengus, sea lamprey Petromyzon marinus and Atlantic salmon Salmo salar, were the primary anadromous species for the sampled rivers. Regardless of the spatial resolution or the pathway of incorporation, annual nutrient pulses from spawning anadromous fishes had a positive effect on isotopic enrichment at all trophic levels (biofilm, 1·2-5·4‰; macro-invertebrates, 0·0-6·8‰; fish, 1·2-2·6‰). Community-wide niche space shifted toward the marine-nutrient source, but the total ecological niche space did not always increase with MDN inputs. The time-integrated marine-nutrient resource contribution to the diet of S. salar parr and brook trout Salvelinus fontinalis ranged between 16·3 and 36·0% during anadromous fish-spawning periods. The high degree of spatio-temporal heterogeneity in marine-nutrient subsidies from anadromous fishes lead to both direct and indirect pathways of MDN incorporation into stream food webs. This suggests that organisms at many trophic levels derive a substantial proportion of their energy from marine resources when present. The current trend of declining anadromous fish populations means fewer nutrient-rich marine subsidies being delivered to rivers, diminishing the ability to sustain elevated riverine productivity.


Asunto(s)
Migración Animal , Peces , Cadena Alimentaria , Ríos , Animales , Océano Atlántico , Isótopos de Carbono/análisis , Dieta , Invertebrados , Isótopos de Nitrógeno/análisis , Salmón , Salmonidae , Trucha
4.
Fungal Genet Biol ; 101: 34-45, 2017 04.
Artículo en Inglés | MEDLINE | ID: mdl-28285895

RESUMEN

Previously, we demonstrated that when Ustilago maydis (DC) Cda., a phytopathogenic basidiomycete and the causal agent of corn smut, is grown in the vicinity of maize embryogenic calli in a medium supplemented with the herbicide Dicamba, it developed gastroid-like basidiocarps. To elucidate the molecular mechanisms involved in the basidiocarp development by the fungus, we proceeded to analyze the transcriptome of the process, identifying a total of 2002 and 1064 differentially expressed genes at two developmental stages, young and mature basidiocarps, respectively. Function of these genes was analyzed with the use of different databases. MIPS analysis revealed that in the stage of young basidiocarp, among the ca. two thousand differentially expressed genes, there were some previously described for basidiocarp development in other fungal species. Additional elements that operated at this stage included, among others, genes encoding the transcription factors FOXO3, MIG3, PRO1, TEC1, copper and MFS transporters, and cytochromes P450. During mature basidiocarp development, important up-regulated genes included those encoding hydrophobins, laccases, and ferric reductase (FRE/NOX). The demonstration that a mapkk mutant was unable to form basidiocarps, indicated the importance of the MAPK signaling pathway in this developmental process.


Asunto(s)
Dicamba/farmacología , Cuerpos Fructíferos de los Hongos/genética , Transcriptoma/efectos de los fármacos , Ustilago/genética , Cuerpos Fructíferos de los Hongos/efectos de los fármacos , Cuerpos Fructíferos de los Hongos/crecimiento & desarrollo , Proteínas Fúngicas/biosíntesis , Perfilación de la Expresión Génica , Regulación Fúngica de la Expresión Génica/efectos de los fármacos , Enfermedades de las Plantas/microbiología , Ustilago/efectos de los fármacos , Ustilago/crecimiento & desarrollo , Ustilago/patogenicidad , Zea mays/microbiología
5.
Biol Lett ; 13(9)2017 09.
Artículo en Inglés | MEDLINE | ID: mdl-28931730

RESUMEN

Migratory decisions in birds are closely tied to environmental cues and fat stores, but it remains unknown if the same variables trigger bat migration. To learn more about the rare phenomenon of bat migration, we studied departure decisions of female common noctules (Nyctalus noctula) in southern Germany. We did not find the fattening period that modulates departure decisions in birds. Female noctules departed after a regular evening foraging session, uniformly heading northeast. As the day of year increased, migratory decisions were based on the interactions among wind speed, wind direction and air pressure. As the migration season progressed, bats were likely to migrate on nights with higher air pressure and faster tail winds in the direction of travel, and also show high probability of migration on low-pressure nights with slow head winds. Common noctules thus monitor complex environmental conditions to find the optimal migration night.


Asunto(s)
Migración Animal , Animales , Quirópteros , Femenino , Alemania , Estaciones del Año , Viento
6.
Infection ; 43(2): 201-6, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25573274

RESUMEN

We studied serotypes circulating dengue virus (DENV) cases, entomological Breteau index, rain-fall index and epidemiology of groups affected during the 2010 outbreak in Nuevo Leon, Mexico. From 2,271 positive cases, 94% were dengue classic and 6% dengue hemorrhagic fever; DENV1 was mainly isolated (99%) (Central-American lineage of American-African-genotype). We found correlation between two environmental phenomena (Increment of rainfall and vector-indexes) (p ≤ 0.05) with epidemiological, clinical and risk of DENV-1 ongoing transmission.


Asunto(s)
Virus del Dengue , Dengue/epidemiología , Dengue/virología , Brotes de Enfermedades , Dengue Grave/virología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Niño , Preescolar , Dengue/historia , Virus del Dengue/clasificación , Virus del Dengue/genética , Femenino , Genotipo , Historia del Siglo XXI , Humanos , Lactante , Masculino , México/epidemiología , Persona de Mediana Edad , Filogenia , Vigilancia de la Población , Estaciones del Año , Serogrupo , Dengue Grave/epidemiología , Dengue Grave/historia , Adulto Joven
7.
Pflugers Arch ; 465(8): 1087-99, 2013 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-23440457

RESUMEN

A comparative analysis of a hyperpolarization-activated ion current present in amphibian oocytes was performed using the two-electrode voltage-clamp technique in Xenopus laevis, Xenopus tropicalis, and Ambystoma mexicanum. This current appears to be driven mainly by Cl(-) ions, is independent of Ca(2+), and is made evident by applying extremely negative voltage pulses; it shows a slow activating phase and little or no desensitization. The pharmacological profile of the current is complex. The different channel blocker used for Cl(-), K(+), Na(+) and Ca(2+) conductances, exhibited various degrees of inhibition depending of the species. The profiles illustrate the intricacy of the components that give rise to this current. During X. laevis oogenesis, the hyperpolarization-activated current is present at all stages of oocytes tested (II-VI), and the amplitude of the current increases from about 50 nA in stage I to more than 1 µA in stage VI; nevertheless, there was no apparent modification of the kinetics. Our results suggest that the hyperpolarization-activated current is present both in order Anura and Urodela oocytes. However, the electrophysiological and pharmacological characteristics are quite perplexing and seem to suggest a mixture of ionic conductances that includes the activation of both anionic and cationic channels, most probably transiently opened due to the extreme hyperpolarizion of the plasma membrane. As a possible mechanism for the generation of the current, a kinetic model which fits the data suggests the opening of pores in the plasma membrane whose ion selectivity is dependent on the extracellular Cl(-) concentration. The extreme voltage conditions could induce the opening of otherwise latent pores in plasma membrane proteins (i.e., carriers), resembling the ´slippage´ events already described for some carriers. These observations should be valuable for other groups trying to express cloned, voltage-dependent ion channels in oocytes of amphibian in which hyperpolarizing voltage pulses are applied to activate the channels.


Asunto(s)
Anfibios/metabolismo , Anfibios/fisiología , Canales Iónicos/metabolismo , Potenciales de la Membrana/fisiología , Oocitos/metabolismo , Ambystoma mexicanum/metabolismo , Ambystoma mexicanum/fisiología , Animales , Proteínas de Transporte de Anión/metabolismo , Proteínas de Transporte de Catión/metabolismo , Membrana Celular/metabolismo , Membrana Celular/fisiología , Fenómenos Electrofisiológicos/fisiología , Concentración de Iones de Hidrógeno , Xenopus laevis/metabolismo , Xenopus laevis/fisiología
8.
Appl Opt ; 52(14): 3311-7, 2013 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-23669845

RESUMEN

We report a free-space quantum key distribution system designed for high-speed key transmission in urban areas. Clocking the system at gigahertz frequencies and efficiently filtering background enables higher secure key rates than those previously achieved by similar systems. The transmitter and receiver are located in two separate buildings 300 m apart in downtown Madrid and they exchange secure keys at rates up to 1 Mbps. The system operates in full bright daylight conditions with an average secure key rate of 0.5 Mbps and 24 h stability without human intervention.


Asunto(s)
Redes de Comunicación de Computadores/instrumentación , Seguridad Computacional/instrumentación , Almacenamiento y Recuperación de la Información/métodos , Dispositivos Ópticos , Procesamiento de Señales Asistido por Computador/instrumentación , Telecomunicaciones/instrumentación , Diseño de Equipo , Análisis de Falla de Equipo , Teoría Cuántica
9.
Neurobiol Stress ; 25: 100551, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37362419

RESUMEN

Psychosocial stress has increased considerably in our modern lifestyle, affecting global mental health. Deficits in attentional control are cardinal features of stress disorders and pathological anxiety. Studies suggest that changes in the locus coeruleus-norepinephrine system could underlie the effects of stress on top-down attentional control. However, the impact of psychosocial stress on attentional processes and its underlying neural mechanisms are poorly understood. This study aims to investigate the effect of psychosocial stress on attentional processing and brain signatures. Evoked potentials and pupillary activity related to the oddball auditory paradigm were recorded before and after applying the Montreal Imaging Stress Task (MIST). Electrocardiogram (ECG), salivary cortisol, and subjective anxiety/stress levels were measured at different experimental periods. The control group experienced the same physical and cognitive effort but without the psychosocial stress component. The results showed that stressed subjects exhibited decreased P3a and P3b amplitude, pupil phasic response, and correct responses. On the other hand, they displayed an increase in Mismatch Negativity (MMN). N1 amplitude after MIST only decreased in the control group. We found that differences in P3b amplitude between the first and second oddball were significantly correlated with pupillary dilation and salivary cortisol levels. Our results suggest that under social-evaluative threat, basal activity of the coeruleus-norepinephrine system increases, enhancing alertness and decreasing voluntary attentional resources for the cognitive task. These findings contribute to understanding the neurobiological basis of attentional changes in pathologies associated with chronic psychosocial stress.

10.
J Neonatal Perinatal Med ; 16(1): 169-177, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36314218

RESUMEN

BACKGROUND: Multisystemic inflammatory syndrome in children (MIS-C) is a novel disease that is associated with the severe acute respiratory syndrome coronavirus 2 (SARS-CoV2). MIS-C usually affects children older than 5 years of age and adolescents, with a median of 8-years and an interquartile range of 3 to 11 years. A multisystemic inflammatory disease has been described in neonates and named MIS-N (multisystemic inflammatory syndrome in Neonates). We report three cases of Mexican newborns with MIS-N presenting with multiorgan compromise and a positive anti-SARS-CoV-2 IgG who developed Kawasaki disease (KD)-like cardiac features and discuss the current dilemma regarding diagnosis and treatment in these patients.


Asunto(s)
COVID-19 , Síndrome Mucocutáneo Linfonodular , Recién Nacido , Adolescente , Niño , Humanos , Preescolar , COVID-19/complicaciones , SARS-CoV-2 , ARN Viral , Síndrome Mucocutáneo Linfonodular/complicaciones , Síndrome Mucocutáneo Linfonodular/diagnóstico
14.
J Biomech ; 94: 49-58, 2019 Sep 20.
Artículo en Inglés | MEDLINE | ID: mdl-31358285

RESUMEN

Aortic valve stenosis is associated with an elevated left ventricular pressure and transaortic pressure drop. Clinicians routinely use Doppler ultrasound to quantify aortic valve stenosis severity by estimating this pressure drop from blood velocity. However, this method approximates the peak pressure drop, and is unable to quantify the partial pressure recovery distal to the valve. As pressure drops are flow dependent, it remains difficult to assess the true significance of a stenosis for low-flow low-gradient patients. Recent advances in segmentation techniques enable patient-specific Computational Fluid Dynamics (CFD) simulations of flow through the aortic valve. In this work a simulation framework is presented and used to analyze data of 18 patients. The ventricle and valve are reconstructed from 4D Computed Tomography imaging data. Ventricular motion is extracted from the medical images and used to model ventricular contraction and corresponding blood flow through the valve. Simplifications of the framework are assessed by introducing two simplified CFD models: a truncated time-dependent and a steady-state model. Model simplifications are justified for cases where the simulated pressure drop is above 10 mmHg. Furthermore, we propose a valve resistance index to quantify stenosis severity from simulation results. This index is compared to established metrics for clinical decision making, i.e. blood velocity and valve area. It is found that velocity measurements alone do not adequately reflect stenosis severity. This work demonstrates that combining 4D imaging data and CFD has the potential to provide a physiologically relevant diagnostic metric to quantify aortic valve stenosis severity.


Asunto(s)
Estenosis de la Válvula Aórtica/fisiopatología , Válvula Aórtica/fisiopatología , Modelos Cardiovasculares , Válvula Aórtica/diagnóstico por imagen , Estenosis de la Válvula Aórtica/diagnóstico por imagen , Velocidad del Flujo Sanguíneo/fisiología , Tomografía Computarizada Cuatridimensional , Hemodinámica/fisiología , Humanos , Hidrodinámica
15.
Plant Sci ; 287: 110198, 2019 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-31481193

RESUMEN

Aiming to counteract B deficiency impacts, plants have developed different strategies in order to reach an optimal growth in soils with limited B availability. These include B transport mechanisms that involves a facilitated transport, via channel proteins, and a high-affinity active transport driven by borate transporters. The AtNIP5;1 channel protein is a member of Major Intrinsic Protein family which facilitates B influx into the roots under low B supply. In order to explore the phytohormone-dependent regulation of AtNIP5;1, the effects of abscisic acid (ABA), ethylene, auxins and cytokinins on the activity of AtNIP5;1 promoter were evaluated using the reporter line pNIP5;1-GUS. The results show that ABA treatment increased pAtNIP5;1 activity. Besides, a larger B uptake was found following ABA treatment under B deficiency suggesting a role of ABA inducing B uptake. The ethylene precursor 1-aminocyclopropane-1-carboxylic acid (ACC) caused an induction of AtNIP5;1 expression although did not correlate with higher B concentrations nor with an improvement in root growth. On the contrary, auxins and cytokinins caused slight changes in pAtNIP5;1 induction. Altogether, these results show a regulatory role of phytohormones in AtNIP5;1 promoter what may affect B transport. The herein provided information may contribute to better understand the regulation of B transport in plants towards minimizing B deficiency impacts on agriculture.


Asunto(s)
Acuaporinas/metabolismo , Proteínas de Arabidopsis/metabolismo , Arabidopsis/metabolismo , Boro/metabolismo , Regulación de la Expresión Génica de las Plantas , Reguladores del Crecimiento de las Plantas/metabolismo , Ácido Abscísico/metabolismo , Acuaporinas/genética , Arabidopsis/citología , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Transporte Biológico , Citocininas/metabolismo , Etilenos/metabolismo , Genes Reporteros , Ácidos Indolacéticos/metabolismo , Raíces de Plantas/citología , Raíces de Plantas/genética , Raíces de Plantas/metabolismo
16.
Ann Burns Fire Disasters ; 32(4): 261-266, 2019 Dec 31.
Artículo en Inglés | MEDLINE | ID: mdl-32431574

RESUMEN

Burn lesions are one of the most devastating forms of trauma. Taking care of this type of lesion generates high costs and may lead to irreversible consequences that limit the daily activities of these patients. This is a two-year descriptive epidemiological study of burned patients treated in a specialized hospital in Mexico City. Data from 38 patients admitted to this hospital were analyzed. Population mean age was 41 years: a higher frequency of men aged 27 to 55 years were affected. The most common mechanism was direct flame, and upper and lower extremities were most frequently affected. Mean affected body surface area was 32.5%. A total of 63% required cutaneous grafting: it was observed that those grafted early (10.5 versus 41.8 days) spent fewer days in the ICU and a lower percentage of them contracted sepsis (62% versus 78%). Patients with Pseudomona aeruginosa had a longer hospital stay and underwent a greater number of surgeries for skin grafting. No difference was observed between graft integration percentages. Early grafting (<7 days) resulted in a shorter stay in the ICU and fewer overall total days in the hospital, as well as a lower rate of sepsis and admission to the ICU. The Pseudomona infection group had a longer hospital stay, greater number of surgical procedures for skin grafting and there was no difference in graft integration percentages.


Les brûlures font partie des traumatismes les plus dévastateurs, aux conséquences irréversibles pouvant laisser des handicaps définitifs. Le coût de leur prise en charge est élevé. Nous présentons une étude épidémiologique basée sur 38 patients hospitalisés en 2 ans dans un CTB de Mexico. La population la plus touchée est l'homme jeune (27 à 55 ans, moyenne 41). La brûlure est due à une flamme, touche 32,5% de la SCT, atteint préférentiellement les extrémités supérieure et inférieure. Une greffe est nécessaire dans 63% des cas. Les patients greffés précocement, aux alentours de J10 (J41,8 ailleurs), restent moins longtemps en réanimation comme dans le CTB et ont moins d'accidents septiques (62% VS 78%). La survenue d'une infection à Pseudomonas æruginosa entraîne un allongement de la durée de séjour et la nécessité de plus de séances de greffes, sans différence quant à leur intégration.

17.
J Econ Entomol ; 111(1): 491-494, 2018 02 09.
Artículo en Inglés | MEDLINE | ID: mdl-29182772

RESUMEN

The monitoring of a pest population often relies on the identification of individuals from traps. For area-wide programs utilizing the sterile insect technique, the further identification of the mated status of females found in traps is of utmost importance. For the Mediterranean fruit fly, Ceratitis capitata (Wiedemann) (Diptera: Tephritidae), this is usually verified through the assessment of sperm in the spermathecae. However, this can be misleading for species where there are other sperm storage organs such as the ventral receptacle. Here, we studied the relative importance of sperm storage in the ventral receptacle compared to the spermathecae for females from 5 to 18 d of age. Furthermore, we studied how sperm can be identified in the ventral receptacle or spermathecae after females were recovered from traps. We found no effect of female age on likelihood of sperm storage. Sperm could be identified in both sperm storage organs at 7 or 14 d after females had been placed in traps. We found that the ventral receptacle is a more reliable indicator of female mated status. Thus, we propose that if no sperm are found in the spermathecae, program managers should revise the ventral receptacle before assuming that females are not mated. This test may also be relevant to other pest tephritids that store even more sperm in the ventral receptacle than C. capitata.


Asunto(s)
Ceratitis capitata/fisiología , Conducta Sexual Animal , Espermatozoides/fisiología , Factores de Edad , Animales , Femenino , Control de Insectos , Masculino , Reproducción , Factores de Tiempo
18.
Mol Immunol ; 103: 63-70, 2018 11.
Artículo en Inglés | MEDLINE | ID: mdl-30205305

RESUMEN

The Surface Immunogenic Protein (SIP) of Group B Streptococcus (GBS) had been described as a good target for vaccine development. To date, SIP has been reported as a highly conserved protein, and in a mouse model it induces protection against lethal GBS challenge. Also, similar effects have been described by intranasal immunization with a SIP-based vaccine. In this study, we show the immune response induced by an oral SIP-based vaccine formulated on alum in a mouse model. Our vaccine can reduce vaginal GBS colonization and induce specific SIP-antibodies with opsonophagocytosis activities against GBS. Moreover, we observed the activation of T-cells producing IFN-γ, TNF-α, IL-10, IL-2, and increased expression of the transcription factor T-bet, suggesting a Th1-type humoral response. The oral SIP-based vaccine is a novel alternative in the development of a vaccine against GBS.


Asunto(s)
Antígenos Bacterianos/inmunología , Infecciones Estreptocócicas/inmunología , Streptococcus agalactiae/inmunología , Vacunas/inmunología , Vagina/inmunología , Administración Oral , Compuestos de Alumbre/administración & dosificación , Compuestos de Alumbre/química , Animales , Anticuerpos Antibacterianos/inmunología , Antígenos Bacterianos/química , Femenino , Células HL-60 , Humanos , Ratones Endogámicos C57BL , Infecciones Estreptocócicas/microbiología , Infecciones Estreptocócicas/prevención & control , Streptococcus agalactiae/efectos de los fármacos , Streptococcus agalactiae/fisiología , Vacunación/métodos , Vacunas/administración & dosificación , Vacunas/química , Vagina/efectos de los fármacos , Vagina/microbiología
19.
Int J Nanomedicine ; 13: 2349-2363, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29713166

RESUMEN

INTRODUCTION: One of the main issues in the medical field and clinical practice is the development of novel and effective treatments against infections caused by antibiotic-resistant bacteria. One avenue that has been approached to develop effective antimicrobials is the use of silver nanoparticles (Ag-NPs), since they have been found to exhibit an efficient and wide spectrum of antimicrobial properties. Among the main drawbacks of using Ag-NPs are their potential cytotoxicity against eukaryotic cells and the latent environmental toxicity of their synthesis methods. Therefore, diverse green synthesis methods, which involve the use of environmentally friendly plant extracts as reductive and capping agents, have become attractive to synthesize Ag-NPs that exhibit antimicrobial effects against resistant bacteria at concentrations below toxicity thresholds for eukaryotic cells. PURPOSE: In this study, we report a green one-pot synthesis method that uses Acacia rigidula extract as a reducing and capping agent, to produce Ag-NPs with applications as therapeutic agents to treat infections in vivo. MATERIALS AND METHODS: The Ag-NPs were characterized using transmission electron microscopy (TEM), high-resolution TEM, selected area electron diffraction, energy-dispersive spectroscopy, ultraviolet-visible, and Fourier transform infrared. RESULTS: We show that Ag-NPs are spherical with a narrow size distribution. The Ag-NPs show antimicrobial activities in vitro against Gram-negative (Escherichia coli, Pseudomonas aeruginosa, and a clinical multidrug-resistant strain of P. aeruginosa) and Gram-positive (Bacillus subtilis) bacteria. Moreover, antimicrobial effects of the Ag-NPs, against a resistant P. aeruginosa clinical strain, were tested in a murine skin infection model. The results demonstrate that the Ag-NPs reported in this work are capable of eradicating pathogenic resistant bacteria in an infection in vivo. In addition, skin, liver, and kidney damage profiles were monitored in the murine infection model, and the results demonstrate that Ag-NPs can be used safely as therapeutic agents in animal models. CONCLUSION: Together, these results suggest the potential use of Ag-NPs, synthesized by green chemistry methods, as therapeutic agents against infections caused by resistant and nonresistant strains.


Asunto(s)
Acacia/química , Antiinfecciosos/síntesis química , Antiinfecciosos/farmacología , Nanopartículas del Metal/química , Plata/farmacología , Animales , Antiinfecciosos/química , Bacillus subtilis/efectos de los fármacos , Farmacorresistencia Bacteriana Múltiple/efectos de los fármacos , Escherichia coli/efectos de los fármacos , Femenino , Tecnología Química Verde/métodos , Pruebas de Sensibilidad Microbiana , Microscopía Electrónica de Transmisión , Extractos Vegetales/química , Infecciones por Pseudomonas/tratamiento farmacológico , Infecciones por Pseudomonas/microbiología , Pseudomonas aeruginosa/efectos de los fármacos , Ratas Wistar , Plata/química , Espectrometría por Rayos X , Espectroscopía Infrarroja por Transformada de Fourier
20.
Rev. otorrinolaringol. cir. cabeza cuello ; 83(1): 66-69, mar. 2023. ilus
Artículo en Español | LILACS | ID: biblio-1431955

RESUMEN

El bad split es un término clínico que refiere a una fractura no planificada que ocurre al momento de realizar una osteotomía sagital de rama mandibular (OSRM). Afecta aproximadamente al 2,3% de los pacientes y se han descrito factores de riesgo tales como la presencia de terceros molares mandibulares, edad avanzada al momento de la cirugía, técnica de osteotomía inadecuada, entre otros. Se recomienda efectuar manio-bras preventivas para evitar la aparición de patrones de fractura no deseados al realizar la OSRM. Sin embargo, al momento de pesquisar un bad split, éste debe ser tratado por un equipo capacitado y de manera oportuna para evitar retardo en la consolidación, infecciones y secuestros óseos que puedan comprometer los resultados de la cirugía. En este artículo se presenta el manejo de un caso clínico de bad split bilateral intraoperatorio por el Servicio de Cirugía Maxilofacial del Hospital San José, enfatizando su tratamiento quirúrgico.


Bad Split is a clinical term referring to an unplanned fracture that occurs during the bilateral sagittal split osteotomy (BSSO). It affects approximately 2,3% of the patients undergoing orthognathic surgery and several risk factors have been described such as the presence of mandibular third molars, advanced age at the moment of orthognathic surgery, inadequate osteotomy technique, etc. Preventive maneuvers are recommended in order to avoid the appearance of undesired fracture patterns during BSSO. However, if a bad split is detected it must be managed and treated by a qualified team to avoid further complications such as delayed bone consolidation, bone infection and necrosis. In this article we present the management of a case of bilateral bad split by the Maxillofacial Surgery Service of Hospital San José, emphasizing on its surgical treatment.


Asunto(s)
Humanos , Femenino , Adulto , Osteotomía/efectos adversos , Cirugía Ortognática/métodos , Osteotomía Sagital de Rama Mandibular/efectos adversos , Complicaciones Intraoperatorias , Mandíbula/cirugía , Fracturas Mandibulares
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