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1.
Int J Biol Macromol ; 261(Pt 2): 129649, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38266847

RESUMO

The production of poly-3-hydroxybutyrate (PHB) on an industrial scale remains a major challenge due to its higher production cost compared to petroleum-based plastics. As a result, it is necessary to develop efficient fermentative processes using low-cost substrates and identify high-value-added applications where biodegradability and biocompatibility properties are of fundamental importance. In this study, grape residues, mainly grape skins, were used as the sole carbon source in Azotobacter vinelandii OP cultures for PHB production and subsequent nanoparticle synthesis based on the extracted polymer. The grape residue pretreatment showed a high rate of conversion into reducing sugars (fructose and glucose), achieving up to 43.3 % w w-1 without the use of acid or external heat. The cultures were grown in shake flasks, obtaining a biomass concentration of 2.9 g L-1 and a PHB accumulation of up to 37.7 % w w-1. PHB was characterized using techniques such as Fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), and differential scanning calorimetry (DSC). The formation of emulsified PHB nanoparticles showed high stability, with a particle size between 210 and 240 nm and a zeta potential between -12 and - 15 mV over 72 h. Owing to these properties, the produced PHB nanoparticles hold significant potential for applications in drug delivery.


Assuntos
Poli-Hidroxibutiratos , Vitis , Carbono , Poliésteres/química , Polímeros , Hidroxibutiratos/química
2.
Rev Chilena Infectol ; 39(2): 126-131, 2022 04.
Artigo em Espanhol | MEDLINE | ID: mdl-35856984

RESUMO

BACKGROUND: Fever in infants younger than 90 days may reflect a serious bacterial infection, so blood cultures (BC) are taken routinely and the patient is hospitalized. The observation time to detect occult bacteremia is not well established. AIM: To describe type and positivity time of isolated bacteria in blood cultures in infants under 90 days admitted for fever. METHODS: Retrospective, descriptive study. Positive blood cultures taken between 2014-2016 in young infants admitted for fever were included. Identification and time of positivity of each bacteria, clinical, laboratory and demographic data were recorded. Demographic variables and the clinical outcome was obtained. RESULTS: There were 172 positive blood cultures, only 51 met inclusion criteria. Of these, 21 microorganisms were pathogenic (Escherichia coli: 10, Streptococcus agalactiae: 3, Streptococcus pyogenes: 3, others: 5) and 30 were considered contamination, mainly coagulase negative Staphylococcus. In relation to the total sample, the median time of positivity was 10 hrs. At 24 hours of culture, bacterial growth was detected in 94% of the sample. CONCLUSION: The pathogenic bacteria isolated in the blood cultures of patients younger than 90 days who were admitted with fever correspond mainly to Gram negative bacilli and streptococci. All isolated pathogens were detected before 24 h of incubation.


Assuntos
Bacteriemia , Bacteriemia/diagnóstico , Bacteriemia/microbiologia , Criança , Escherichia coli , Febre , Hospitais , Humanos , Lactente , Estudos Retrospectivos , Streptococcus agalactiae , Streptococcus pyogenes
3.
Rev. chil. infectol ; 39(2): 126-131, abr. 2022. tab
Artigo em Espanhol | LILACS | ID: biblio-1388349

RESUMO

INTRODUCCIÓN: En neonatos y lactantes bajo 90 días de vida la fiebre constituye un signo clínico relevante ya que puede corresponder a una infección bacteriana grave, por lo que se toman hemocultivos de forma rutinaria y el paciente es hospitalizado. Aún no existe una recomendación respecto al tiempo de observación necesario una vez internado el paciente. OBJETIVO: Describir las bacterias aisladas en hemocultivos de lactantes bajo 90 días de vida hospitalizados por fiebre y el tiempo de detección de crecimiento microbiano en los mismos. ¨MÉTODO: Estudio descriptivo, retrospectivo. Se revisaron hemocultivos positivos tomados entre 2014 y 2016 en neonatos y lactantes < 90 días de edad. Se obtuvieron las identificaciones, tiempo de positividad de las bacterias, así como datos clínicos, de laboratorio y demográficos. RESULTADOS: Se identificaron 172 hemocultivos positivos, 51 cumplían los criterios de inclusión. De éstos, 21 microorganismos fueron patógenos (Escherichia coli: 10, Streptococcus agalactiae: 3, Streptococcus pyogenes: 3, otros: 5) y 30 se consideraron contaminación, principalmente Staphylococcus coagulasa negativa. En relación al total de la muestra, la mediana del tiempo de positividad fue de 10 h. A las 24 h de cultivo se detectó crecimiento bacteriano en 94% de la muestra. CONCLUSIÓN: Las bacterias patógenas aisladas en los hemocultivos de pacientes < 90 días de edad, que ingresaron con fiebre, corresponden principalmente a bacilos gramnegativos y estreptococos. Todos los patógenos aislados fueron detectados antes de 24 h de incubación.


BACKGROUND: Fever in infants younger than 90 days may reflect a serious bacterial infection, so blood cultures (BC) are taken routinely and the patient is hospitalized. The observation time to detect occult bacteremia is not well established. AIM: To describe type and positivity time of isolated bacteria in blood cultures in infants under 90 days admitted for fever. METHODS: Retrospective, descriptive study. Positive blood cultures taken between 2014-2016 in young infants admitted for fever were included. Identification and time of positivity of each bacteria, clinical, laboratory and demographic data were recorded. Demographic variables and the clinical outcome was obtained. RESULTS: There were 172 positive blood cultures, only 51 met inclusion criteria. Of these, 21 microorganisms were pathogenic (Escherichia coli: 10, Streptococcus agalactiae: 3, Streptococcus pyogenes: 3, others: 5) and 30 were considered contamination, mainly coagulase negative Staphylococcus. In relation to the total sample, the median time of positivity was 10 hrs. At 24 hours of culture, bacterial growth was detected in 94% of the sample. CONCLUSION: The pathogenic bacteria isolated in the blood cultures of patients younger than 90 days who were admitted with fever correspond mainly to Gram negative bacilli and streptococci. All isolated pathogens were detected before 24 h of incubation.


Assuntos
Humanos , Lactente , Criança , Bacteriemia/diagnóstico , Bacteriemia/microbiologia , Streptococcus agalactiae , Streptococcus pyogenes , Estudos Retrospectivos , Escherichia coli , Febre , Hospitais
4.
Front Bioeng Biotechnol ; 9: 761510, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34733834

RESUMO

Millions of tonnes of tyre waste are discarded annually and are considered one of the most difficult solid wastes to recycle. A sustainable alternative for the treatment of vulcanised rubber is the use of microorganisms that can biotransform polymers and aromatic compounds and then assimilate and mineralise some of the degradation products. However, vulcanised rubber materials present great resistance to biodegradation due to the presence of highly hydrophobic cross-linked structures that are provided by the additives they contain and the vulcanisation process itself. In this work, the biodegradation capabilities of 10 fungal strains cultivated in PDA and EM solid medium were studied over a period of 4 weeks. The growth of the strains, the mass loss of the vulcanised rubber particles and the surface structure were analysed after the incubation period. With the white rot fungi Trametes versicolor and Pleurotus ostreatus, biodegradation percentages of 7.5 and 6.1%, respectively, were achieved. The FTIR and SEM-EDS analyses confirmed a modification of the abundance of functional groups and elements arranged on the rubber surface, such as C, O, S, Si, and Zn, due to the biological treatment employed. The availability of genomic sequences of P. ostreatus and T. versicolor in public repositories allowed the analysis of the genetic content, genomic characteristics and specific components of both fungal species, determining some similarities between both species and their relationship with rubber biodegradation. Both fungi presented a higher number of sequences for laccases and manganese peroxidases, two extracellular enzymes responsible for many of the oxidative reactions reported in the literature. This was confirmed by measuring the laccase and peroxidase activity in cultures of T. versicolor and P. ostreatus with rubber particles, reaching between 2.8 and 3.3-times higher enzyme activity than in the absence of rubber. The integrative analysis of the results, supported by genetic and bioinformatics tools, allowed a deeper analysis of the biodegradation processes of vulcanised rubber. It is expected that this type of analysis can be used to find more efficient biotechnological solutions in the future.

5.
J Hosp Infect ; 108: 113-119, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33157170

RESUMO

BACKGROUND: The coronavirus disease 2019 pandemic has caused problems with respirator supplies. Re-use may minimize the impact of the shortage, but requires the availability of an efficient and safe decontamination method. AIM: To determine whether low-temperature-steam-2%-formaldehyde (LTSF) sterilization is effective, preserves the properties of filtering facepiece (FFP) respirators and allows safe re-use. METHODS: Fourteen unused FFP2, FFP3 and N95 respirator models were subjected to two cycles of decontamination cycles. After the second cycle, each model was inspected visually and accumulated residual formaldehyde levels were analysed according to EN 14180. After one and two decontamination cycles, the fit factor (FF) of each model was tested, and penetration tests with sodium chloride aerosols were performed on five models. FINDINGS: Decontamination physically altered three of the 14 models. All of the residual formaldehyde values were below the permissible threshold. Irregular decreases and increases in FF were observed after each decontamination cycle. In the sodium chloride aerosol penetration test, three models obtained equivalent or superior results to those of the FFP classification with which they were marketed, both at baseline and after one and two cycles of decontamination, and two models had lower filtering capacity. CONCLUSION: One and two decontamination cycles using LTSF did not alter the structure of most (11/14) respirators tested, and did not degrade the fit or filtration capacity of any of the analysed respirators. The residual formaldehyde levels complied with EN 14180. This reprocessing method could be used in times of shortage of personal protective equipment.


Assuntos
Descontaminação/métodos , Formaldeído/farmacologia , Dispositivos de Proteção Respiratória/virologia , Esterilização/métodos , Adulto , Aerossóis/efeitos adversos , COVID-19/diagnóstico , COVID-19/epidemiologia , COVID-19/prevenção & controle , COVID-19/virologia , Reutilização de Equipamento , Formaldeído/análise , Humanos , Masculino , Máscaras/tendências , Máscaras/virologia , Equipamento de Proteção Individual/provisão & distribuição , Dispositivos de Proteção Respiratória/provisão & distribuição , SARS-CoV-2/genética , Cloreto de Sódio/análise , Vapor/efeitos adversos , Ventiladores Mecânicos/provisão & distribuição , Ventiladores Mecânicos/virologia
6.
Chemosphere ; 259: 127414, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32599381

RESUMO

The photocatalytic degradation of simazine (SIM) was investigated using zinc oxide/graphene oxide (ZnO/GO) composite materials under visible light irradiation. The reaction kinetics was studied to optimize the reaction parameters for efficient degradation of SIM. Batch studies were performed to investigate the effects of initial reaction pH, the loading of the ZnO onto GO, and mass of catalyst on the removal of SIM from aqueous solution. A pH of 2 was determined to be the optimal reaction pH for the different ZnO-loaded GO catalysts. In addition, a mass of 40 mg of catalyst in the reaction was observed to be the most effective for the catalysts synthesized using 20 and 30 mmol of Zn2+ ions; whereas a mass of 10 mg was most effective for the ZnO/GO composite material synthesized using 10 mmol Zn2+ ions. The reaction was observed to follow a second-order kinetics for the degradation process. Furthermore, the synthesized ZnO/GO composite catalysts resulted in higher reaction rates than those observed for pure ZnO. The 30 mmol ZnO/GO composite expressed a rate of SIM degradation ten times greater than the rate observed for pure ZnO, and sixty-two times greater than the rate of photolysis. In addition, the catalyst cycling exhibited a constant photocatalytic activity for the ZnO/GO composite over three reaction cycles without the need of a conditioning cycle.


Assuntos
Grafite/química , Simazina/química , Óxido de Zinco/química , Catálise , Luz , Fotólise
7.
Sci Rep ; 10(1): 2568, 2020 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-32054941

RESUMO

A novel superparamagnetic state has been observed in high quality La0.7Sr0.3MnO3 (LSMO) thin films directly grown by rf-sputtering on SiOx/Si(100) substrates. The films are nanostructured without grain boundaries, constituted by locally epitaxial nanoregions grown layer-by-layer with out-of-plane (012) preferential orientation, induced by the constrain of the native silicon oxide. Low magnetic field ZFC-FC magnetization curves show a cross-over from superparamagnetic to ferromagnetic state dependent of the thickness. The thicker film (140 nm) exhibits typical ferromagnetic order. The thinner films (40 and 60 nm) exhibit superparamagnetic behavior attributed to interacting ferromagnetic monodomain nanoregions with critical size, random in-plane oriented, where the inter-monodomain boundaries with surface spin-glass structure regulate the blocking of magnetization depending on the magnetic field intensity. M(H) hysteresis loops showed noticeable coercive fields in all samples, larger than those reported for LSMO. Such properties of half-metal LSMO film foresee potential integration in new Si-technology nanodevices in Spintronics.

8.
Microchem J ; 141: 188-196, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30510325

RESUMO

Tin oxide, SnO2, nanomaterial was synthesized and tested for the removal of Cu2+ and Ni2+ ions from aqueous solutions. Various parameters for the binding were investigated in batch studied, which included pH, time, temperature, and interferences. In addition, isotherm studied were performed to determine the maximum binding capacity for both Cu2+ and Ni2+ ions. The optimal binding pH determined from the effects of pH were to be at pH 5 for both the Cu2+ and Ni2+ ions. The isotherm studies were performed at temperatures of 4°C, 25 °C, and 45 °C for both the Cu2+ and Ni2+ ions and were found to follow the Langmuir isotherm model. The binding capacities for the Cu2+ ions were 2.63 mg/g, 2.95 mg/g and 3.27 mg/g at the aforementioned temperatures, respectively. Whereas the binding capacities for Ni2+ were 0.79 mg/g, 1.07 mg/g, and 1.46 mg/g at the respective temperatures. The determined thermodynamic parameters for the binding showed that the binding processes for the reactions were endothermic, as the ΔG was observed to decrease with decreasing temperatures. As well the ΔH was 28.73 kJ/mol for Cu2+ (III) and 13.37 kJ/mol for Ni2+. The ΔS was observed to be 92.65 J/mol for Cu2+ and 54.53 J/mol for Ni2+. The free energy of adsorption for the Cu2+ was determined to be 13.99 kJ/mol and the activation energy for the binding of Ni2+ was determined to be 8.09 KJ/mol. The activation energy data indicate that the reaction was occurring through chemisorption.

9.
J Dairy Sci ; 101(9): 8021-8031, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29960776

RESUMO

Nutritional programming caused by feed restriction during the early life may counteract the profitability of the dairy sheep farm. However, most studies have been focused exclusively on the prenatal period, and scarce information regarding the effect of milk replacer (MR) restriction on feed efficiency [residual feed intake (RFI)] and progesterone patterns of replacement ewe lambs is available. Therefore, in the present study 40 Assaf female newborn lambs were penned individually and assigned randomly to 1 of 2 treatment groups (n = 20 per treatment). The first group of lambs was fed MR ad libitum (ADLB), whereas the second one (restricted, RES) only received approximately 62.5% of the MR intake measured in the ADLB group. All the lambs were weighed twice a week until they were 35 d old. Then 8 lambs from each group were killed and a morphological study of the gut was performed. Moreover, a piece of liver was cut to measure fat content and oxidative status. The rest of the ewe lambs (24) were weaned and offered a total mixed ration ad libitum to calculate the RFI during the replacement phase. Plasma samples were collected when ewe lambs were 8 mo old to perform a nontargeted metabolomic analysis on a hybrid quadrupole-time-of-flight mass spectrometer coupled to an ultra-high-performance liquid chromatographic system. Progesterone was also measured weekly on serum samples by sequential competitive immunoassay until the end of the experiment (9.5 mo old). The results observed indicate that moderated MR restriction promoted differences in the morphology of the gut of the 35-d-old lambs, but not in the apparent digestibility or feed efficiency traits (RFI) during the replacement phase. However, there was a trend toward reduced live body weight of the RES ewe lambs when they were 9.5 mo old. Moreover, progesterone patterns revealed that only 1 RES versus 4 ADLB ewe lambs had ovulated for the first time at the end of the experiment. This evidence suggests the existence of long-term effects caused by early feed restriction with negative consequences on live body weight and reproductive traits of replacement ewe lambs.


Assuntos
Fenômenos Fisiológicos da Nutrição Animal , Ingestão de Energia/fisiologia , Ovinos/crescimento & desenvolvimento , Ração Animal , Animais , Animais Recém-Nascidos/crescimento & desenvolvimento , Peso Corporal , Dieta , Feminino , Leite , Gravidez , Progesterona/sangue
10.
Cir Cir ; 86(2): 132-139, 2018.
Artigo em Espanhol | MEDLINE | ID: mdl-29809190

RESUMO

INTRODUCTION: Intraoperative neurophysiological monitoring (IONM) is a procedure that uses neurophysiological techniques in order to evaluate the motor and sensitive systems during surgeries that endanger the nervous system. METHOD: The approach, scope, target population, and clinical questions to be answered were defined. A systematic search of the evidence was conducted step by step; during the first stage, clinical practice guidelines were collected, during the second stage systematic reviews were obtained, and during the third stage, clinical trials and observational studies were procured. The MeSH nomenclature and free related terminology were used, with no language restrictions and a 5-10 years frame. The quality of the evidence was graded using the CEPD and SIGN scales. RESULTS: Obtained using the search algorrhythms of 892 documents. Fifty-eight were chosen to be included in the qualitative synthesis. A meta-analysis was not possible due to the heterogeneity of the studies. CONCLUSIONS: Eighteen recommendations were issued and will support the adequate use of the IONM.


INTRODUCCIÓN: El monitoreo neurofisiológico intraoperatorio (MNIO) es un procedimiento que emplea técnicas neurofisiológicas con la finalidad de evaluar los sistemas motor y sensitivo durante cirugías que ponen en riesgo al sistema nervioso. MÉTODO: Se definieron el enfoque, los alcances, la población diana y las preguntas clínicas por resolver. Se realizó una búsqueda sistematizada de la evidencia por etapas. En la primera, se buscaron guías de práctica clínica; en la segunda, revisiones sistemáticas; y en la tercera, ensayos clínicos y estudios observacionales. Se utilizaron los términos MeSH y libres correspondientes, sin restricciones de lenguaje y con una temporalidad de 5 a 10 años. Se graduó la calidad de la evidencia utilizando las escalas CEPD y SIGN. RESULTADOS: Mediante los algoritmos de búsqueda se obtuvieron 892 documentos, y se seleccionaron 58 para la inclusión de la síntesis cualitativa. Debido a la heterogeneidad entre los estudios, no fue posible realizar metaanálisis. CONCLUSIONES: Se emitieron 18 recomendaciones, las cuales servirán como apoyo para la adecuada utilización del MNIO.


Assuntos
Monitorização Neurofisiológica Intraoperatória , Centros de Cuidados de Saúde Secundários , Centros de Atenção Terciária , Adulto , Criança , Humanos , Guias de Prática Clínica como Assunto
11.
Animal ; 12(9): 1838-1846, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29362009

RESUMO

The present study was designed to describe the effects of early feed restriction of Merino lambs on feed efficiency during the fattening period by examining ruminal microbiota and fermentation parameters, gastrointestinal morphology, digestibility or liver proteome. In total, 24 male Merino lambs were randomly assigned to two experimental treatments (n=12 per treatment). Lambs of the first group (ad libitum (ADL)) were kept permanently with the dams, whereas the other 12 lambs (restricted (RES)) were milk restricted. When lambs reached a live BW (LBW) of 15 kg, all the animals were offered the same complete pelleted diet (35 g dry matter/kg LBW per day) until slaughter at a LBW of 27 kg. The RES lambs showed poorer feed efficiency during the fattening period when compared with the ADL group (feed to gain ratio, 3.69 v. 3.05, P<0.001). No differences were observed in ruminal microbiota, fermentation parameters or apparent digestibility. However, the proportion of the small intestine and the length of ileal villi were reduced in the RES lambs. In total, 26 spots/proteins were identified in the liver proteomic profile, with significant differences (P<0.05) between experimental treatments, suggesting a higher catabolism of proteins and a reduction in ß-oxidation of fatty acids in RES lambs when compared with the ADL animals. In conclusion, early feed restriction of Merino lambs during the suckling period promotes long-term effects on the small intestine and the proteomic profile of the liver, which may influence the metabolic use of nutrients, thus negatively affecting feed efficiency during the fattening phase.


Assuntos
Ração Animal , Fígado , Proteômica , Ovinos , Tecido Adiposo , Fenômenos Fisiológicos da Nutrição Animal , Animais , Dieta , Fígado/metabolismo , Masculino , Proteoma , Distribuição Aleatória , Ovinos/fisiologia , Desmame
12.
Rev Gastroenterol Mex (Engl Ed) ; 83(1): 51-61, 2018.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-29287906

RESUMO

INTRODUCTION: Lysosomal acid lipase deficiency (LAL-D) causes progressive cholesteryl ester and triglyceride accumulation in the lysosomes of hepatocytes and monocyte-macrophage system cells, resulting in a systemic disease with various manifestations that may go unnoticed. It is indispensable to recognize the deficiency, which can present in patients at any age, so that specific treatment can be given. The aim of the present review was to offer a guide for physicians in understanding the fundamental diagnostic aspects of LAL-D, to successfully aid in its identification. METHODS: The review was designed by a group of Mexican experts and is presented as an orienting algorithm for the pediatrician, internist, gastroenterologist, endocrinologist, geneticist, pathologist, radiologist, and other specialists that could come across this disease in their patients. An up-to-date review of the literature in relation to the clinical manifestations of LAL-D and its diagnosis was performed. The statements were formulated based on said review and were then voted upon. The structured quantitative method employed for reaching consensus was the nominal group technique. RESULTS: A practical algorithm of the diagnostic process in LAL-D patients was proposed, based on clinical and laboratory data indicative of the disease and in accordance with the consensus established for each recommendation. CONCLUSION: The algorithm provides a sequence of clinical actions from different studies for optimizing the diagnostic process of patients suspected of having LAL-D.


Assuntos
Doença de Wolman/diagnóstico , Algoritmos , Diagnóstico Diferencial , Humanos , México , Doença de Wolman/patologia , Doença de Wolman/fisiopatologia , Doença de Wolman
13.
Microchem J ; 133: 614-621, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29081543

RESUMO

A Rancieite type material (K2Mn4O9) nanomaterial was synthesized and tested for the removal of chromium (III) and chromium (VI) from aqueous solutions. The synthesized nanomaterial was characterized using powder XRD and SEM. XRD showed weak diffraction peaks at only at the angles associated with K2Mn4O9. The SEM corroborated that the nanoparticles were present; however, the nanoparticles were clustered into larger aggregates. Batch studies were performed to determine the optimum pH, capacity, time dependency, interferences, and the thermodynamics of the binding. The optimum pH for the binding of Cr(III) and Cr(VI) were determined to be pH 5 and pH 2, respectively. Isotherm studies were performed at temperatures of 4 , 25 , and 45 for Cr(III) and Cr(VI) and showed binding capacities of 21.7 mg/g, 36.5 mg/g, 41.8 mg/g for Cr(III). The Cr(VI) binding capacities were 4.22 mg/g, 4.08 mg/g, and 3.25 mg/g at the respective temperatures. The thermodynamic studies showed that the binding processes for the reactions were spontaneous and endothermic, with a ΔH was 17.54 kJ/mol for Cr(III) and 6.05 kJ/mol for Cr(VI). The of sorption for Cr(III) were determined to be -3.88 kJ/mol, -5.83 kJ/mol and -7.03 kJ/mol at the aforementioned temperatures. The ΔG values for the Cr(VI) sorption were determined to be -4.89 kJ/mol, -5.64 kJ/mol, and -6.05 kJ/mol. In addition, the ΔS values for Cr(III) and Cr(VI) were determined to be 77.92 J/mol and 39.49 J/mol, respectively. The thermodynamics indicate that the binding of Cr(III) and Cr(VI) is spontaneous and endothermic.

14.
Phys Chem Chem Phys ; 19(21): 14129-14140, 2017 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-28524207

RESUMO

The kinetics of oxygen incorporation (in-diffusion process) and excorporation (out-diffusion process), in YBa2Cu3O6+x (YBCO) epitaxial thin films prepared using the chemical solution deposition (CSD) methodology by the trifluoroacetate route, was investigated by electrical conductivity relaxation measurements. We show that the oxygenation kinetics of YBCO films is limited by the surface exchange process of oxygen molecules prior to bulk diffusion into the films. The analysis of the temperature and oxygen partial pressure influence on the oxygenation kinetics has drawn a consistent picture of the oxygen surface exchange process enabling us to define the most likely rate determining step. We have also established a strategy to accelerate the oxygenation kinetics at low temperatures based on the catalytic influence of Ag coatings thus allowing us to decrease the oxygenation temperature in the YBCO thin films.

15.
Rev. Univ. Ind. Santander, Salud ; 49(1): 75-84, Marzo 20, 2017. tab, graf
Artigo em Espanhol | LILACS | ID: biblio-897091

RESUMO

RESUMEN Introducción: El comportamiento caótico de la dinámica cardiaca normal y aguda ha sido caracterizado en el contexto de la teoría de los sistemas dinámicos y la geometría fractal. Objetivo: Desarrollar una nueva metodología diagnóstica para la evaluación de la dinámica cardiaca en pacientes de UCI, durante 16 horas. Metodología: Este es un estudio en pacientes ingresados a Cuidados Intensivos posquirúrgicos (UCI) y sujetos sanos, tomando un total de 47 registros electrocardiográficos continuos y/o Holter, normales y con patología aguda, evaluados en 16 horas. Se desarrolló una inducción con dos dinámicas normales y tres de UCI; a partir de los valores máximos y mínimos de la frecuencia cardiaca/hora y total de latidos/hora, registrados durante 16 horas se construyeron atractores para evaluar sus espacios de ocupación y dimensión fractal, con el fin de establecer diferencias e igualdades respecto a estados normales y patológicos. Se realizaron medidas de sensibilidad y especificidad con las dinámicas restantes para comparar el diagnostico matemático con el diagnóstico clínico. Resultados: Los espacios de ocupación de los atractores cardiacos diferencian dinámicas cardiacas normales de dinámicas con enfermedad crónica y aguda, detectando además dinámicas patológicas con valores superiores a los límites de normalidad, logrando valores de sensibilidad de 0,937 y especificidad del 1. Conclusión: se estableció una nueva metodología de evaluación de la dinámica cardiaca de utilidad para el seguimiento clínico en pacientes de UCI.


ABSTRACT Introduction: The chaotic behavior of normal and acute cardiac dynamics has been characterized in the context of theory of dynamical systems and fractal geometry. Objective: to establish a new diagnostic method for assessing cardiac dynamics in ICU patients, for 16 hours. Methodology: This is a study in post-surgical patients admitted to intensive care (ICU) and in healthy subjects, taking a total of 47 continuous electrocardiographic recordings and/ or Holter, normal and acute pathology, evaluated in 16 hours. Induction with two normal and three UCI dynamics was developed; from the maximum and minimum values of the heart/time and total frequency of beats/minute for 16 hours recorded attractors they were constructed to assess their areas of occupation and fractal dimension, in order to establish differences and equalities regarding normal states and pathological. Sensitivity and specificity measurements were performed with the remaining dynamic to compare mathematical diagnosis with clinical diagnosis. Results: Space occupancy heart attractors differ dynamic normal cardiac dynamics with chronic and acute illness, in addition detecting dynamic pathological with above normal limits values, achieving sensitivity values of 0.937 and specificity of 1. Conclusion: a new methodology for evaluating cardiac dynamics useful for clinical monitoring in ICU patients was established.


Assuntos
Humanos , Dinâmica não Linear , Frequência Cardíaca , Unidades de Terapia Intensiva , Fractais , Matemática , Modelos Teóricos
16.
Rev. osteoporos. metab. miner. (Internet) ; 8(1): 15-23, ene.-mar. 2016. graf
Artigo em Espanhol | IBECS | ID: ibc-151229

RESUMO

Introducción: La adherencia al tratamiento oral del paciente con osteoporosis es baja, con un alto porcentaje de abandonos durante el primer año. La consecuencia más notable es la falta de respuesta terapéutica. Objetivo: Conocer la percepción de los facultativos involucrados en el abordaje del paciente osteoporótico en relación a la adherencia terapéutica de estos pacientes. Material y métodos: Estudio descriptivo transversal realizado mediante una encuesta de opinión dirigida a médicos de Atención Primaria y Atención Especializada involucrados en el tratamiento de la osteoporosis. Los participantes fueron seleccionados mediante muestreo intencionado. Resultados: El cuestionario fue contestado por 235 especialistas de Reumatología (54,5%), Traumatología (10,6%) y Atención Primaria (18,7%). En opinión del 43,8% de los encuestados, más de un 25% de los pacientes olvida alguna vez tomar el tratamiento. Según el 34,9%, más de 75% de los pacientes están concienciados con el tratamiento. Los efectos secundarios y la complejidad de la administración son las razones mayoritarias que propician un cambio de medicación, con una importancia media de 7,94±2,06 y 6±2,01 puntos respectivamente en una escala 0-10. Conclusiones: Los facultativos percibieron baja adherencia terapéutica asociada fundamentalmente a los efectos secundarios, a la polimedicación y a la falta de comunicación entre profesionales. Espaciar la dosificación y el uso de formas galénicas solubles podrían ser opciones para facilitar la adherencia del paciente al tratamiento con bisfosfonatos orales. Mejorar la educación sobre la importancia de la enfermedad o aumentar el seguimiento del paciente serían algunos de los aspectos que podrían favorecer la adherencia terapéutica (AU)


Introduction: Adherence to oral treatment of patients with osteoporosis is low, with a high dropout rate in the first year. The most noteworthy result is the lack of therapeutic response. Objective: To ascertain the perception of physicians working with osteoporotic patients regarding adherence of these patients. Methods: Cross-sectional study conducted by opinion survey aimed at primary care physicians and specialists involved in osteoporosis treatment. Participants were selected by purposive sampling. Results: The questionnaire was answered by 235 specialists encompassing rheumatology (54.5%), orthopedics (10.6%) and primary care (18.7%). In 43.8% of participants, more than 25% of patients sometimes forget to take their treatment. According to 34.9%, more than 75% of patients are aware of treatment. Side effects and management complexity are the majority reasons that lead to a change in medication, mean value of 7.94±2.06 6±2.01 points respectively on a 0-10 scale. Conclusions: Overall, medical specialists attributed low adherence to side effects, polypharmacy and lack of communication between professionals. Dosage and space use of soluble dosage forms may be options to facilitate patient adherence to treatment with oral bisphosphonates. Improved education concerning the importance of the disease or increased patient monitoring could foster adherence (AU)


Assuntos
Humanos , Osteoporose/tratamento farmacológico , Conservadores da Densidade Óssea/uso terapêutico , Difosfonatos/uso terapêutico , Cooperação do Paciente/estatística & dados numéricos , Adesão à Medicação/estatística & dados numéricos , Pesquisas sobre Atenção à Saúde/estatística & dados numéricos , Médicos/estatística & dados numéricos
17.
Appl Radiat Isot ; 107: 191-194, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26519921

RESUMO

This work introduces a new, versatile and robust X-ray detector with hemispherical 2π geometry, based on a set of 15 small cylindrical proportional counters located in a hexagonal and pentagonal fullerene C60 pattern, at the same distance from the center (where a sample is placed). The counteranode consists of stainless steel sewing needles with spherical tips measuring approximately 80 µm in diameter. The space between the counters and the sample could contain air, the same gas as the counters or vacuum. This allows a significant increase in the count rates by a factor approximately equal to the number of counters connected. It is shown that an energy resolution of 20% for 5.9 keV photons can be obtained, and a global counting rate of around 10(6)counts/s is achievable by the 15 Needle Anode Proportional Counters (NAPCs) operating in parallel mode, in our setup.


Assuntos
Radiometria/instrumentação , Eletrodos , Desenho de Equipamento , Humanos , Fótons , Radiometria/estatística & dados numéricos , Raios X
18.
Matronas prof ; 17(2): 62-69, 2016. tab
Artigo em Espanhol | IBECS | ID: ibc-153569

RESUMO

OBJETIVO: Describir la satisfacción de la mujer respecto al rol de la matrona/matrón en la atención del parto en una Maternidad de la ciudad de Santiago de Chile, perteneciente al Sistema de Salud Público. MÉTODO: Estudio cualitativo. Se realizaron entrevistas semiestructuradas a 14 mujeres chilenas, puérperas de parto vaginal, de entre 19 y 43 años, sin patologías asociadas. Se llevó a cabo un análisis del contenido de los datos. RESULTADOS: En el análisis de las entrevistas se valoraron cinco categorías: I) experiencia general del parto; II) la matrona/matrón: un profesional cercano y cómplice en el proceso (III) y un pilar en el manejo del dolor; IV) habilidades comunicacionales y entrega de información, y V) la matrona/matrón como ente de empoderamiento durante el parto. Con respecto al rol de la matrona/matrón, el componente relacional destaca por encima de las habilidades técnicas: el buen trato, la compañía, la contención emocional, la cercanía y la entrega de información. Las mujeres esperan empatía, amabilidad y motivación, y que la matrona/matrón contribuya a disminuir la ansiedad y el dolor, de modo que se sientan apoyadas y puedan vivir una mejor experiencia. CONCLUSIÓN: La calidad de la atención determina una buena experiencia de parto. El rol del profesional matrona/matrón es de gran relevancia en este proceso, lo que hace necesaria una formación orientada no sólo a las competencias técnicas, sino también, y fundamentalmente, a las comunicacionales y relacionales, de modo que sea posible ofrecer una atención de calidad que favorezca el estado emocional óptimo de la madre


OBJECTIVE: To describe the satisfaction of women regarding the role of the midwife in delivery care in a Maternity belonging to the public health system in Santiago de Chile. METHOD: Qualitative study using semi-structured interviews with 14 postpartum low risk women, undergoing a vaginal delivery between 19 and 43 years old. A content analysis of the data was performed. RESULTS: The analysis of these interviews revealed five categories: overall experience of childbirth, Midwife: a close professional an accomplice in the process, a fundamental pillar in pain management, communication skills and information delivery, the midwife as an entity of empowerment during childbirth. Regarding the role of the midwife, stands out the relational component far over the technical skills: good treat, company, closeness and provision of information. Women expect empathy, kindness, containment, motivation that helps reducing anxiety and pain, this allows them feeling supported and live a better experience. CONCLUSION: Quality of care determines a good birth experience The role of the midwife is of great importance during this process, requiring technical skills and training, but mainly communication and relational skills are needs, to provide a real quality care and ensure an optimal maternal emotional state


Assuntos
Humanos , Feminino , Gravidez , Papel Profissional , Parto Obstétrico/métodos , Individualidade , Tocologia , Satisfação do Paciente/estatística & dados numéricos , Modelos Organizacionais , Qualidade da Assistência à Saúde/estatística & dados numéricos
19.
Am J Rhinol Allergy ; 29(1): e13-7, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25590308

RESUMO

BACKGROUND: There is a need for controlled trials to guide the perioperative management of patients undergoing endoscopic sinus surgery (ESS). The authors performed a pilot multicenter trial to compare two types of saline delivery devices in this population. METHODS: Patients were randomized to high volume saline irrigation with a squeeze bottle and low volume saline spray after ESS in patients with chronic rhinosinusitis (CRS). Surgeons were blinded to treatment, and one-month postoperative scores for sinonasal outcomes [Sinonasal Outcome Test-22 (SNOT-22)] scale, nasal and sinus symptom score (NSS), and perioperative sinus endoscopy (POSE) scale were compared with preoperative scores. RESULTS: Nine centers provided data for 86 patients. All three outcomes measures improved significantly for both groups. Saline spray: SNOT-22 48.8 versus. 23.7, treatment effect 25.1 (95% confidence interval [CI], 17.9-32.2), POSE 21.1 versus. 8.4, treatment effect 12.7 (95% CI, 9.2-16.1), and NSS 8.2 versus 5.0, treatment effect 3.1 (95% CI, 1.4-4.9) pre- and postoperatively, respectively (all p < 0.0001). Squeeze bottle: SNOT-22 49.5 versus 23.6, treatment effect 25.9 (95% CI, 20.3-31.6), POSE 18.6 versus 9.2, treatment effect 9.3, (95% CI 6.7-12.0), and NSS 9.0 versus 5.7, treatment effect 3.3 (95% CI, 2.3-4.3) pre- and postoperatively, respectively (all p < 0.0001). Analysis of variance did not identify a difference between the two treatment groups. Subgroup analysis based on preoperative disease severity did not change the nonassociation of saline bottle with outcome measures. Post hoc sample size calculation determined that 176 patients is required to detect an 8.9-point difference in SNOT-22 scores. CONCLUSION: In this pilot multicenter trial examining patients with chronic rhinosinusitis undergoing ESS, both squeeze bottle and saline spray showed significant improvement in SNOT-22, POSE, and NSS scores at one-month postoperatively. Because the study was nonpowered, we cannot rule out a potential difference between the two treatment groups.


Assuntos
Seios Paranasais/cirurgia , Rinite/cirurgia , Sinusite/cirurgia , Adulto , Doença Crônica , Endoscopia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Cloreto de Sódio/administração & dosagem
20.
J Laryngol Otol ; 128(9): 814-7, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25166215

RESUMO

OBJECTIVE: To determine the effect of pterygopalatine fossa injection with xylocaine and adrenaline on: surgical field bleeding and blood loss during functional endoscopic sinus surgery for chronic rhinosinusitis, and the duration of the procedure. METHODS: A prospective, single-blinded, controlled trial was performed in a tertiary care academic centre. A total of 45 patients undergoing functional endoscopic sinus surgery for chronic rhinosinusitis, whose disease was symmetrical based on computed tomography grading, were included. A unilateral pterygopalatine fossa injection with 1 per cent xylocaine and 1:100 000 adrenaline was performed after the induction of anaesthesia. The contralateral side served as the control. The operating surgeon, who was blinded to the injected side, assessed the surgical field using a validated six-item grading system. Blood loss, blood pressure, heart rate and end-tidal carbon dioxide were recorded every 15 minutes for each side separately, and duration of surgery was noted. RESULTS: There was no statistically significant difference in the surgical field grade between the injected and non-injected sides (p = 0.161). There were no differences in blood loss or duration of surgery. CONCLUSION: Pterygopalatine fossa injection prior to functional endoscopic sinus surgery did not decrease intra-operative surgical field bleeding, blood loss or duration of surgery.


Assuntos
Anestésicos Locais/administração & dosagem , Perda Sanguínea Cirúrgica/prevenção & controle , Epistaxe/prevenção & controle , Fossa Pterigopalatina/cirurgia , Vasoconstritores/administração & dosagem , Adulto , Idoso , Doença Crônica , Epinefrina/administração & dosagem , Epinefrina/uso terapêutico , Feminino , Humanos , Lidocaína/administração & dosagem , Lidocaína/uso terapêutico , Masculino , Pessoa de Meia-Idade , Assistência Perioperatória , Estudos Prospectivos , Método Simples-Cego , Sinusite/cirurgia , Resultado do Tratamento , Vasoconstritores/uso terapêutico
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