Objetivo: Describir las características clínicas y epidemiológicas de los pacientes con intoxicación por metanol en dos hospitales públicos. Materiales y métodos: Serie de casos retrospectiva, se ...evaluó 41 historias clínicas de pacientes que ingresaron a emergencia con diagnóstico de Intoxicación por metanol, en el periodo 2018-2022, en dos hospitales públicos de Lima-Perú: Hospital Nacional Arzobispo Loayza y Hospital Hipólito Unanue. Resultados: De los 41 pacientes, 35 eran varones, con una media de edad de 44,4 años. Cerca del 50% ingresó a Unidad de cuidados intensivos (UCI), 23/41(56,1%) requirió hemodiálisis. Todos los pacientes presentaron acidosis metabólica severa anión gap elevado. A las 48 horas de ingreso 9/41(21,9%) pacientes fallecieron. De los sobrevivientes, 23/41(56,1%) presentaron secuelas: 21 pacientes con neuropatía óptica tóxica y 2 pacientes con secuela motora por accidente cerebrovascular hemorrágico. Se evidenció menor valor del nivel de pH (6,7 vs 7,1, p < 0,001) y bicarbonato (3 mmol/L vs 4,9 mmol/L, p= 0,004), así como mayor nivel de lactato (9,6 mmol/L vs 2,3 mmol/L, p<0,001) y sodio (142,5 mmol/L vs 138 mmol/L, p < 0,036) en el grupo de fallecidos comparado con los vivos. Conclusión La intoxicación por metanol, continúa siendo una condición que deja secuelas y puede llevar a fallecimiento, su principal manifestación es la acidosis metabólica severa anión gap alto, asociada a síntomas respiratorios y neurológicos; el tratamiento se basa en la administración de etanol, bicarbonato y hemodiálisis.
Disminuir el impacto ambiental derivado del uso de combustibles fósiles necesita el desarrollo de fuentes de energía renovables, y la producción sostenible de combustibles líquidos. Los éteres de ...oximetileno (OMEs), son compuestos oxigenados que han surgido como una potencial alternativa para sustituir el combustible Diesel. El uso de estos éteres en los motores disminuye la formación de hollín y óxidos de nitrógeno (NOx) durante la combustión. Dentro de esta familia de compuestos, el 1,1-dimetoximetano (OME1) tiene especial interés, no solo por su uso como solvente industrial o como intermediario químico, sino, también porque puede ser usado como materia prima para la producción de OMEs de cadena larga. La síntesis directa de OME1 involucra la oxidación selectiva de metanol sobre catalizadores bifuncionales, los cuales han sido objeto de estudio durante las últimas décadas. Este trabajo resume las principales características de los distintos sistemas catalíticos desarrollados, los cuales juegan un papel fundamental para la producción comercial del 1,1-dimetoximetano.
Tithonia diversifolia se distribuye en trópico y subtrópico de México y es una valiosa fuente de compuestos bioactivos. Existen varios métodos para la extracción de compuestos bioactivos, sin ...embargo, su rendimiento depende de varios factores, por lo que es importante seleccionar las mejores condiciones.
PtCo based nanoparticles in alloy structure were synthesized using the microwave-assisted reduction method. These nanoparticles were deposited on different carbon supporting materials. Here, these ...supporting materials such as rGO (reduced graphene oxide), rGO-VC (vulcan carbon) and AC-VC (activated carbon-vulcan carbon) were used and the methanol oxidation reaction (MOR) activity of single carbon support and hybrid carbon support material in the presence of PtCo nanoparticles were investigated at the same molar concentration. The average particle size of the PtCo nanoparticles detected in the TEM analysis was found to be 3.55 ± 0.64 nm. The MOR activity of the PtCo@rGO, PtCo@rGO-VC and PtCo@AC-VC catalysts was determined, where the anodic peak current of PtCo@AC-VC was determined as 73 mA/cm2. It has been observed that PtCo nanoparticles with carbon hybrid support structures are more advantageous than single support structures due to the synergistic effect between carbon support structures and providing a larger surface area. Compared to previous studies, the MOR activity of PtCo@AC-VC is quite high. It can be stated that PtCo@AC-VC has comparable catalytic activity compared to the commercial available anode catalyst.
•PtCo nanoparticles were synthesized using the microwave-assisted reduction method.•The average particle size of the PtCo nanoparticles was found to be 3.55 nm.•The anodic peak potential of PtCo@AC-VC was determined as 73 mA/cm2.•PtCo@AC-VC is a highly efficient catalyst in direct methanol fuel cells.
The Abraham solvation parameter model, a linear free energy relationship (LFER) approach, has been used to characterize a polymeric zwitterionic (sulfobetaine) column in HILIC mode. When acetonitrile ...(MeCN) is used in the preparation of mobile phases the main solute characteristics affecting the chromatographic behavior of analytes are the molecular size and the hydrogen-bonding (both acidity and basicity) interactions. The former property is more favorable in the acetonitrile-rich mobile phase, reducing thus the retention, but the latter reveals a higher affinity for the water layer adsorbed on the stationary phase, enhancing retention. However, if the aprotic acetonitrile is replaced by methanol, a hydrogen-bond acidic solvent, solute hydrogen-bond basicity does not contribute any more to retention, quite the opposite. Thus, a slightly different selectivity is observed in methanol/water than in acetonitrile/water. Normal-phase mode and HILIC-MeCN share the same main factors affecting retention. For reversed-phase and immobilized artificial membrane (IAM) chromatography, the solute molecular size increase retention because of the lower amount of energy required in the formation of a cavity in the solvated stationary phase. On the contrary, the analyte hydrogen-bond basicity favors interactions with the hydroorganic mobile phase and reduces retention. The determined parameters justify the reversed selectivity commonly observed in HILIC in reference to reversed-phase. In most instances, the least retained solutes in reversed-phase are the most retained in HILIC.
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•The Abraham model is used for the characterization of a HILIC column.•Selectivity depends on the organic solvent used, acetonitrile or methanol.•HILIC is compared to normal-phase, reversed-phase and IAM retention selectivity.
In Aquaculture, the use of microalgae is fundamental in the first feeding of native fish species, since their optimal nutritional level favors survival. Successful production of microalgae under ...laboratory conditions depends on the culture medium used during the cryopreservation stage of production. Agricultural fertilizers can be used as a low-cost alternative culture media that promotes cell growth and cryopreservation. The objective was to evaluate the effect of two culture media on population growth (PG) and post-thawing viability (PTV) of three microalgal species (Chlorella sp., Desmodesmus sp., and Ankistrodesmus sp.). The PG and PTV were evaluated for F/2 Guillard and Nutrifoliar® culture media. Instantaneous growth rate (K), doubling time (dt), yield (y), and maximum density (md) were evaluated for PG in both culture media. For VCP, 5 and 10 % methanol was used in six treatments. The PTV was classified as no cell damage (NCD), cell damage (CD), and marked lesions (ML). Population growth did not differ among microalgae (p >0.05). T1 resulted in the lowest dt for Desmodesmus sp., (p <0.05). T2 showed the highest y and md for the three microalgae (p <0.05). Regarding post-thawing cell viability, the highest NCD for Chlorella sp. at day (d) 0 was similar between T3 and T4, and at d 5 it occurred in T6; for Desmodesmus sp., at d 0 it occurred in T6, and at d 5 it was similar between T6 and T1; for Ankistrodesmus sp., at d 0 and d 5 it occurred in T3. It is concluded that the culture medium Nutrifoliar®, is a viable alternative and of low cost for the culture and the cryopreservation of microalgae of fresh water.
The aim of this work was to compare the effect of solventsin the UAE on the content of total phenolic compounds (TPC) andin vitroantioxidant capacity DPPH and reducing power (RP) of the whole ...fruitB.alicastrum. The phenolic compounds of the freeze-dried fruit were extractedin an ultrasonic bath for 30 min at 30°C, 100% amplitude and 40 kHzfrequency. The solvents used were: ethanol (Et-OH), methanol (Met-OH),50% ethanol (50% Et-OH) and 50% methanol (50% Met-OH). The UAE ofphenolic compounds of the fruit was improved by adding distilled water tothe organic solvent. The highest TPC content and antioxidant capacity wereobtained with 50% Met-OH. There was a high positive correlation betweenTPC and antioxidant capacity (DPPH and PR). It is suggested to use 50%Met-OH as solvent for UAE of phenolic compounds of fruitB. alicastrum.
El trabajo tuvo como objetivo comparar el efecto de disol-ventes en la EAU sobre el contenido de compuestos fenólicos totales(CFT) y capacidad antioxidantein vitroDPPH y poder reductor (PR) delfruto completoB. alicastrum. Los compuestos fenólicos del fruto liofilizadofueron extraídos en un baño de ultrasonidos durante 30 min a 30°C, 100%de amplitud y 40 kHz de frecuencia. Los disolventes utilizados fueron:etanol (Et-OH), metanol (Met-OH), 50% de etanol (50% Et-OH) y 50% demetanol (50% Met-OH). La EAU de compuestos fenólicos del fruto mejoróadicionando agua destilada al disolvente orgánico. El mayor contenido CFTy la mayor capacidad antioxidante se obtuvieron con 50% Met-OH. Hubouna alta correlación positiva entre CFT y la capacidad antioxidante (DPPHy PR). Se sugiere utilizar 50% Met-OH como disolvente para la EAU decompuestos fenólicos del fruto completoB. alicastrum.
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