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1.
Molecules ; 27(6)2022 Mar 21.
Artículo en Inglés | MEDLINE | ID: mdl-35335389

RESUMEN

Olives treated according to the Spanish-style are firstly treated with caustic soda and then fermented in brine to reduce phenols. Next, olives are packed and subjected to pasteurization. The effect of different high hydrostatic pressure treatments (400 MPa, 4 and 6 min) was evaluated in Spanish-style table olives fermented with olive leaf extract (OLE) and S. cerevisiae compared with thermal pasteurization (P) at 80 °C for 15 min. HHP and P led to a significant reduction in yeast and aerobic mesophiles after the conservation treatment and during storage (300 days). The physical-chemical properties changed slightly during storage, except for olive hardness; olives treated with HHP presented a higher hardness than pasteurized ones. The CIELAB parameter L* decreased until day 300 in most of the treatments, as well as phenols. The HHP treatment led to significantly higher contents of phenolics (even during storage) than olives submitted to P. Some sensory attributes (colour, aspect, hardness, and overall evaluation) decreased during storage. P treatment caused a decrease in appearance, aroma, hardness, and overall evaluation compared to olives treated with HHP. Thus, the application of HHP in table olives to increase the shelf-life can be considered a valid alternative to P.


Asunto(s)
Olea , Presión Hidrostática , Extractos Vegetales , Saccharomyces cerevisiae
2.
J Sci Food Agric ; 100(12): 4449-4456, 2020 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-32388862

RESUMEN

BACKGROUND: The changes in the volatile profile of a pumpkin (Cucurbita moschata, Duch.) purée processed by high pressure thermal (HPT) processing at different pressure and initial temperature intensities (300, 600, 900 MPa and 60, 80 °C, respectively) was evaluated. Headspace solid-phase microextraction (HS-SPME) technique was used for the extraction and concentration of volatile compounds and the analysis was performed by gas chromatography-mass spectrometry (GC-MS). RESULTS: Alcohols were the volatile compounds most abundantly isolated in the headspace of pumpkin purée (control and processed purées had ranges between 43 and 56%), followed by aldehydes (14-28%), hydrocarbons (8-13%) and terpenes (7-10%). Lipid oxidation, Maillard reaction and carotenoids degradation were the main chemical routes of formation of volatile compounds after HPT processing. Initial temperature or pressure intensity of HPT processing, within the ranges tested in this study, did not affect the initial levels of volatile compounds of pumpkin purée. CONCLUSION: HPT processing is an effective technology for the preservation of the original aroma of low acid vegetables such as pumpkin. © 2020 Society of Chemical Industry.


Asunto(s)
Cucurbita/química , Manipulación de Alimentos/métodos , Cromatografía de Gases y Espectrometría de Masas/métodos , Microextracción en Fase Sólida/métodos , Compuestos Orgánicos Volátiles/química , Compuestos Orgánicos Volátiles/aislamiento & purificación , Manipulación de Alimentos/instrumentación , Calor , Odorantes/análisis , Presión
3.
Materials (Basel) ; 17(4)2024 Feb 16.
Artículo en Inglés | MEDLINE | ID: mdl-38399169

RESUMEN

Advanced high-strength steels (AHSSs) are designed for meeting strict requirements, especially in the automotive industry, as a means to directly influence the reduction in the carbon footprint. As rotary friction welding (RFW) has many important advantages over other welding technologies, it plays an important role in the automotive sector. On the above basis, in this work, combinations of the first (complex phase (CP)), second (TWIP (TW)), and third (quenched and partitioned (Q&P)) generations of similar and dissimilar high-alloyed advanced steels have been joined by the RFW process. Having a specific microstructure, rods of CP/CP, Q&P/Q&P, CP/TW, and Q&P/TW steels were welded by employing a homemade adaptation machine under fixed parameters. Microstructural characterization has allowed us to corroborate the metallic bonding of all the tested advanced steels and to identify the different zones formed after welding. Results indicate that the welding zone widens in the center of the workpiece, and under the current friction action, the intermixing region shows the redistribution of solute elements, mostly in the dissimilarly welded steels. Furthermore, because of their complex chemistry and the different mechanical properties of the used steels, dissimilarly welded steels present the most noticeable differences in hardness. The TWIP steel has the lower hardness values, whilst the CP and Q&P steels have the higher ones. As a direct effect of the viscoplastic behavior of the steels established by the thermomechanical processing, interlayers and oxidation products were identified, as well as some typical RFW defects. The electrochemical response of the welded steels has shown that the compositional and microstructural condition mostly affect the corrosion trend. This means that the dissimilarly welded steels are more susceptible to corrosion, especially at the TWIP-steel interface, which is attributed to the energy that is stored in the distorted microstructure of each steel plate as a consequence of the thermomechanical processing during RFW.

4.
bioRxiv ; 2024 Mar 20.
Artículo en Inglés | MEDLINE | ID: mdl-38562893

RESUMEN

Many voice disorders are linked to imbalanced muscle activity and known to exhibit asymmetric vocal fold vibration. However, the relation between imbalanced muscle activation and asymmetric vocal fold vibration is not well understood. This study introduces an asymmetric triangular body-cover model of the vocal folds, controlled by the activation of intrinsic laryngeal muscles, to investigate the effects of muscle imbalance on vocal fold oscillation. Various scenarios were considered, encompassing imbalance in individual muscles and muscle pairs, as well as accounting for asymmetry in lumped element parameters. The results highlight the antagonistic effect between the thyroarytenoid and cricothyroid muscles on the elastic and mass components of the vocal folds, as well as the impact on the vocal process from the imbalance in the lateral cricoarytenoid and interarytenoid adductor muscles. Measurements of amplitude and phase asymmetry were employed to emulate the oscillatory behavior of two pathological cases: unilateral paralysis and muscle tension dysphonia. The resulting simulations exhibit muscle imbalance consistent with expectations in the composition of these voice disorders, yielding asymmetries exceeding 30% for paralysis and below 5% for dysphonia. This underscores the versatility of muscle imbalance in representing phonatory scenarios and its potential for characterizing asymmetry in vocal fold vibration.

5.
J Sci Food Agric ; 93(8): 1820-6, 2013 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-23225211

RESUMEN

BACKGROUND: Lycopene, a bioactive red pigment, represents the most potent in vitro antioxidant among carotenoids. Virgin olive oil contains trace amounts of a wide variety of phytochemicals, which have proven to exert beneficial effects on oxidative stress. Since the ingestion of lycopene together with oil reportedly increases its bioavailability, we evaluated urinary antioxidant capacity after the consumption of a lycopene-enriched virgin olive oil (7 mg lycopene day(-1)) compared with the antioxidant effect produced after the ingestion of a virgin olive oil and a sunflower oil during 5 days, in young (25-30 years of age), middle-aged (35-55 years of age) and elderly (65-85 years of age) subjects. RESULTS: The results showed that the consumption of virgin olive oil increased urinary antioxidant capacity in middle-aged and elderly volunteers, whereas the administration of a lycopene-enriched virgin olive oil produced higher antioxidant effects in all of the three age groups assayed. CONCLUSION: The incorporation of the lycopene-enriched virgin olive oil into the diet may enhance the health-promoting effects of the virgin olive oil, contributing as a functional tool against several disorders where oxidative stress plays an important role.


Asunto(s)
Antioxidantes/metabolismo , Carotenoides/química , Aceites de Plantas/farmacología , Adulto , Anciano , Anciano de 80 o más Años , Carotenoides/farmacología , Estudios Cruzados , Humanos , Licopeno , Persona de Mediana Edad , Aceite de Oliva , Aceites de Plantas/química
6.
Foods ; 12(3)2023 Jan 19.
Artículo en Inglés | MEDLINE | ID: mdl-36766005

RESUMEN

Producing dry-cured meats with relatively high aw and pH allows companies to cut costs to the detriment of microbial control. The purpose of this study was to evaluate for the first time the effect of High Processing Pressure (HPP) and storage temperature on the microbial counts, instrumental color, oxidation and sensory characteristics of sliced Iberian chorizo with high aw and pH. First, 600 MPa was applied for 480 s to sliced chorizo with aw: 0.88 and pH: 6.01, and the treated and untreated samples were stored at 4 or 20 °C for 90 or 180 days. HPP, storage time and storage at 20 °C were successful at decreasing the microbial counts that were initially high. HPP and the storage temperature had a limited detrimental effect, whereas the storage time had a marked adverse effect on oxidation and some sensory traits. Despite the high aw and pH, no safety issues arose initially or during the storage at 4 or 20 °C. In conclusion, for chorizo with high aw and pH favoring high microbial counts, HPP may be an effective hurdle without a noticeable detrimental effect, and the economically convenient storage at 20 °C might be beneficial despite causing moderate quality loss.

7.
Food Sci Nutr ; 11(9): 5512-5522, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37701220

RESUMEN

The main purpose of this study was to evaluate the effect of high-pressure processing (HPP) and storage temperature on the microbial counts, the instrumental color, and the oxidation stability of sliced dry-cured Iberian loin from two categories and two leading companies. 600 MPa for 8 min was sufficient to decrease all the microbial counts without affecting the color and the oxidation status, the effect being modulated by the loin category and company, whose effect on those variables was marked. However, the subsequent 90-day storage softened the initial effect of HPP on microorganisms and allowed a significant effect of HPP to develop on color and oxidation. In addition, the coliform counts were higher after storage at 20°C than at 4°C, suggesting that refrigeration may be needed during long-term storage to ensure loin safety.

8.
Foods ; 11(9)2022 May 04.
Artículo en Inglés | MEDLINE | ID: mdl-35564061

RESUMEN

The top-quality "salchichón" (a fermented dry-cured sausage) is manufactured from Iberian pigs reared outdoors. This work aims to evaluate the effect of hydrostatic high pressure (HHP) and storage temperature on sliced vacuum-packaged top-quality Iberian "salchichón". Two types of "salchichón" (S1 and S2, manufactured at different companies) were processed at 600 MPa for 8 min and stored at 4 and 20 °C for 180 days. Microbiological, physicochemical, and sensory changes were evaluated. Microbiological counts were reduced by HHP treatment and also generally decreased during storage at both temperatures. Lightness and redness of slices decreased during storage at 20 °C, while yellowness values increased. Changes in color were also observed in sensory analysis of the dry-cured sausages. HHP increased lipid and protein oxidation values in S1, whereas protein oxidation increased at 20 °C in S2. S1 was more affected by HHP while S2 was more affected by the temperature of storage. Therefore, despite both products belonging to the same commercial category, slight differences in the composition of both products and/or differences in packaging determined a different behavior after HHP treatment and during storage at different temperatures.

9.
Plants (Basel) ; 11(9)2022 Apr 22.
Artículo en Inglés | MEDLINE | ID: mdl-35567134

RESUMEN

Fleshy fruits represent a valuable resource of economic and nutritional relevance for humanity. The plant cuticle is the external lipid layer covering the nonwoody aerial organs of land plants, and it is the first contact between fruits and the environment. It has been hypothesized that the cuticle plays a role in the development, ripening, quality, resistance to pathogen attack and postharvest shelf life of fleshy fruits. The cuticle's structure and composition change in response to the fruit's developmental stage, fruit physiology and different postharvest treatments. This review summarizes current information on the physiology and molecular mechanism of cuticle biosynthesis and composition changes during the development, ripening and postharvest stages of fleshy fruits. A discussion and analysis of studies regarding the relationship between cuticle composition, water loss reduction and maintaining fleshy fruits' postharvest quality are presented. An overview of the molecular mechanism of cuticle biosynthesis and efforts to elucidate it in fleshy fruits is included. Enhancing our knowledge about cuticle biosynthesis mechanisms and identifying specific transcripts, proteins and lipids related to quality traits in fleshy fruits could contribute to the design of biotechnological strategies to improve the quality and postharvest shelf life of these important fruit crops.

10.
Food Chem ; 343: 128546, 2021 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-33214041

RESUMEN

The effect of high pressure thermal (HPT) processing on the immunoglobulin (IgM, IgA and IgG), and cytokine content (IL-6, IL-8, IL-10, and TNF-α), and antioxidant activity of human milk was analyzed after the application of different treatments between 200, and 800 MPa at low initial temperatures (between -15, and 50 °C) and for 1 s (flash treatments). Low pressures intensities did not induce changes in Igs while at 800 MPa, all combinations reduced the control levels. IL-6 and IL-10 were not affected by any of the treatments applied while IL-8 and TNF-α were reduced at treatments which combined temperatures at 50 °C. In general antioxidant activity was not affected at the processing conditions chosen. The flash HPT treatment applied at 600 MPa and at 0 °C could be the best choice to preserve immunological parameters and the antioxidant activity of human milk.


Asunto(s)
Antioxidantes/química , Citocinas/análisis , Inmunoglobulinas/análisis , Leche Humana/metabolismo , Citocinas/metabolismo , Ensayo de Inmunoadsorción Enzimática , Manipulación de Alimentos/métodos , Humanos , Inmunoglobulinas/metabolismo , Leche Humana/química , Leche Humana/inmunología , Presión , Temperatura
11.
Front Physiol ; 12: 732244, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34539451

RESUMEN

The ambulatory assessment of vocal function can be significantly enhanced by having access to physiologically based features that describe underlying pathophysiological mechanisms in individuals with voice disorders. This type of enhancement can improve methods for the prevention, diagnosis, and treatment of behaviorally based voice disorders. Unfortunately, the direct measurement of important vocal features such as subglottal pressure, vocal fold collision pressure, and laryngeal muscle activation is impractical in laboratory and ambulatory settings. In this study, we introduce a method to estimate these features during phonation from a neck-surface vibration signal through a framework that integrates a physiologically relevant model of voice production and machine learning tools. The signal from a neck-surface accelerometer is first processed using subglottal impedance-based inverse filtering to yield an estimate of the unsteady glottal airflow. Seven aerodynamic and acoustic features are extracted from the neck surface accelerometer and an optional microphone signal. A neural network architecture is selected to provide a mapping between the seven input features and subglottal pressure, vocal fold collision pressure, and cricothyroid and thyroarytenoid muscle activation. This non-linear mapping is trained solely with 13,000 Monte Carlo simulations of a voice production model that utilizes a symmetric triangular body-cover model of the vocal folds. The performance of the method was compared against laboratory data from synchronous recordings of oral airflow, intraoral pressure, microphone, and neck-surface vibration in 79 vocally healthy female participants uttering consecutive /pæ/ syllable strings at comfortable, loud, and soft levels. The mean absolute error and root-mean-square error for estimating the mean subglottal pressure were 191 Pa (1.95 cm H2O) and 243 Pa (2.48 cm H2O), respectively, which are comparable with previous studies but with the key advantage of not requiring subject-specific training and yielding more output measures. The validation of vocal fold collision pressure and laryngeal muscle activation was performed with synthetic values as reference. These initial results provide valuable insight for further vocal fold model refinement and constitute a proof of concept that the proposed machine learning method is a feasible option for providing physiologically relevant measures for laboratory and ambulatory assessment of vocal function.

12.
Data Brief ; 32: 106159, 2020 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-32904214

RESUMEN

This article presents the data set obtained for the research work entitled "Effect of a Ni-P coating on the corrosion resistance of an additive manufacturing carbon steel immersed in a 0.1 M NaCl solution" [1]. Microstructural, mechanical, and electrochemical characterization (using the electrochemical impedance and electrochemical noise spectroscopy technique) is performed on a material obtained by additive manufacturing and the influence of a Ni-P coating on it. The layer sizes and hardness of the substrate are measured, as well as the thickness of the coating and its hardness, values for corrosion resistance, resistance to electrochemical noise and location indices are calculated. The data show an adequate deposition rate for the type of coating, as well as the increase in corrosion resistance when the coating is applied to the steel by additive manufacturing.

13.
Environ Sci Pollut Res Int ; 19(1): 186-200, 2012 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-21717169

RESUMEN

PURPOSE: The purpose of this work is to contribute to the understanding of the photochemical air pollution analysing the levels and temporal variations of surface ozone in two rural areas situated in central-southern Spain. METHOD: The study is based on ozone hourly data recorded during the overall period between January 2008 and November 2009. The seasonal and daily ozone cycles as well as the number of exceedances of the threshold established in the European Ozone Directive have been calculated and analysed. RESULTS: This study presents the first ozone data registered at these two rural sites in the Iberian Peninsula plateau. Ozone shows a clear seasonal variation with the lowest values in January and November. High ozone concentrations are interrelated with high radiation intensities, temperature and wind directions. The information threshold defined in the European Ozone Directives was exceeded six times, while the limit for protection of human health was exceeded more than 40 times. The limits to protect the vegetation were also exceeded. CONCLUSIONS: Porzuna (near Cabañeros National Park) presents higher ozone levels than Argamasilla during the night-time and during the daytime of the summer months. Ozone levels are lower in Argamasilla probably due to fresh emissions from the close industrial area of Puertollano. The ozone exceedances of the limits defined in the Ozone Directive point out an ozone problem in this rural region.


Asunto(s)
Contaminantes Atmosféricos/análisis , Monitoreo del Ambiente , Ozono/análisis , Algoritmos , Humanos , Población Rural , Estaciones del Año , España , Factores de Tiempo , Salud Urbana
14.
J Food Sci ; 77(8): C866-73, 2012 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-22809197

RESUMEN

UNLABELLED: The application of hydrostatic high pressure on a "Songold" plum purée was assessed in comparison with heat pasteurization. To simulate industrial conditions, one-half of the total purée was manufactured with a pretreatment of thermal blanching (TB) and the other half without it (nonthermally blanched, NTB). Changes after thermal treatment and high-pressure processing (HPP: 400, 600 MPa) and after 20 d of refrigerated storage were evaluated. HPP maintained the microbial stability of the purées until the end of the storage period. Polyphenol oxidase activity was lower in TB purées than NTB purées. No treatment was completely effective to stop the enzyme activity, although a significant reduction was reached. Thermally treated purées showed more intense color changes after processing and storage than HP-treated purées. After processing, high-pressure (HP) purées treated at 600 MPa (TB and NTB) increased the extractability of carotenoids compared with initial untreated purée. Nevertheless, at the end of the storage, the highest carotenoid content was found in the TB purée treated at 400 MPa. After processing, total polyphenol levels were similar in all purées. TB and 600 MPa processing was more effective in the maintenance of the polyphenols than the other purées. TB increased the level of antioxidants after storage, compared to NTB purées. A previous TB step is necessary to inactivate browning enzymes before HPP to maintain the levels of bioactive compounds. HPP of plum purée could be a suitable alternative to traditional thermal processing, but more studies are necessary to ensure a major inactivation of polyphenol oxidase. PRACTICAL APPLICATION: High-pressure processing is one of the most successful technologies to obtain high-quality fruit purées without appreciable losses in taste, flavor, color, and nutritive value. However, for the introduction of a new technology, some advantages compared to the traditional thermal treatment need to be emphasized. The application of this technology could be reduced due to resistance of certain enzymes to pressurization. For this reason, in some cases the application of a previous thermal blanching can be necessary at industrial level. However, this can reduce the advantages of HPP application. This paper provides interesting information about the storage stability of plum purées after high-pressure treatments and assesses the need for applying heat pretreatments.


Asunto(s)
Manipulación de Alimentos/métodos , Conservación de Alimentos/métodos , Frutas , Valor Nutritivo , Presión , Prunus , Antioxidantes/análisis , Carotenoides/análisis , Catecol Oxidasa/análisis , Frío , Color , Contaminación de Alimentos/análisis , Microbiología de Alimentos/métodos , Almacenamiento de Alimentos , Calor , Pasteurización , Polifenoles/análisis , Gusto
15.
J Food Sci ; 76(4): C618-25, 2011 May.
Artículo en Inglés | MEDLINE | ID: mdl-22417344

RESUMEN

The application of hydrostatic high pressure on an industrial line of nectarine (Prunus persica L.) purées was assessed in comparison with the traditional thermal treatment of pasteurization. Changes after thermal processing (85 °C, 5 min) and after high-pressure processing (HPP: 450 or 600 MPa for 5 or 10 min) and during the refrigerated storage (60 d) of an industrially produced nectarine purée were evaluated. Conventional heat pasteurization as well as HPP showed similar microorganisms' inactivation and maintained the microbial stability of purées until the end of the refrigerated storage (60 d). In general, thermally treated purée and HP-treated purée at 600 MPa showed more intense color changes after processing than the other treatment. In addition, thermally treated purée showed more intense color changes during storage than HPP. The highest carotenoids extractability was found in those purées treated at the lowest high-pressure-treatment intensity and holding time (450 MPa/5 min), but at the end of the storage (day 60), no differences in individual or total carotenoid levels were found between the purées. HPP at 600 MPa/10 min showed the highest polyphenols content after the treatment and during the storage. At day 0, significantly higher values were found of total antioxidant activity in purée HP-treated at 450 MPa/10 min than in untreated purée; while at the end of the storage, HP-treated purée at 600 MPa/10 min had the highest antioxidant activity. Hydrostatic high-pressure application in the industrial line of nectarine purée presented some advantages compared to the thermal treatment; however, some of the changes found were lessen during the storage period. In addition, more studies need to be carried out for HP-treatment intensity optimization.


Asunto(s)
Bebidas/análisis , Conservación de Alimentos/métodos , Almacenamiento de Alimentos/métodos , Frutas/química , Valor Nutritivo , Carotenoides/análisis , Fenómenos Químicos , Microbiología de Alimentos , Calor , Concentración de Iones de Hidrógeno , Pasteurización , Polifenoles/análisis , Presión , Prunus/química , Refrigeración
16.
Rev. venez. oncol ; 19(4): 277-286, oct.-dic. 2007. ilus, graf, tab
Artículo en Español | LILACS | ID: lil-492950

RESUMEN

El índice de sobrevida libre de enfermedad a 5 años con esquema 5-fluorouracilo/mitomicina/ radiación para carcinomas del conducto anal, alcanza cifras de 65 por ciento de sobrevida libre de enfermedad que deben ser mejoradas. El propósito del trabajo es determinar la respuesta de un nuevo esquema de quimioterapia neoadyuvante y quimiorradioterapia concurrente para carcinoma escamo-celular localmente avanzado del conducto anal. 60 pacientes ingresados entre el 2001 y 2005, 37 fueron incluidos en el estudio. Edad media fue 57 años, con predominio del sexo femenino (73 por ciento). Veinte y cinco pacientes (67 por ciento) presentaron tamaño tumoral > 5 cm, 57 por ciento ganglios linfáticos comprometidos. Se administraron dos ciclos de inducción de 5- fluorouracilo (1 000 mg/m2 días 1-5 y 21-25) más cisplatino (100 mg/m2 días 1 y 21) seguidos de dos ciclos de 5- fluorouracilo (1 000 mg/m2 días 42-46 y 63-67) y mitomicina (10 mg/m2 días 42 y 63) concurrentes con radiación (45 a 59 Gy; inicio día 42) por seis semanas (semanas 7 a 12). Período de seguimiento promedio de 21 meses, se obtuvo respuesta completa en 20 (54 por ciento) pacientes, respuesta parcial en 15 (41 por ciento) pacientes, 27 por ciento sobrevida libre de enfermedad y 35 por ciento de sobrevida libre de colostomía. Los índices de toxicidad grado 3/4: no hematológicos 32 por ciento y hematológicos 54 por ciento. La inducción con 5-fluorouracilo/cisplatino seguida de 5 fluorouracilo/ mitomicina/radiación es eficaz para preservación del esfínter anal y el control local de la enfermedad.


Asunto(s)
Humanos , Masculino , Femenino , Canal Anal/fisiopatología , Carcinoma de Células Escamosas/diagnóstico , Neoplasias del Ano , Quimioterapia/métodos , Quimioterapia , Radioterapia/métodos , Radioterapia , Oncología Médica , Venezuela
17.
CES odontol ; 18(1): 9-13, ene.-feb. 2005. tab
Artículo en Español | LILACS | ID: lil-467185

RESUMEN

La formalina se ha utilizado como agente esterilizante, bactericida y germicida en clínicas y hospitales, sin estudios que soporten su uso o que garanticen los resultados esperados. El formaldehído, en su forma natural es un gas de bajo peso molecular, fácilmente diluible en agua y de olor irritante característico, este agente tiene gran tendencia a polimerizarse haciendo grupos de 3 y 4 moléculas obteniéndose el Trioximetanal o Para – formaldehído (formalina). Se realizó un estudio con 86 piezas de instrumental odontológico utilizando en pacientes de la Clínica CES Sabaneta, el cual luego del lavado corriente, fue expuesto a la formalina por 12 horas, luego se hizo un frotis a cada instrumento. Se incubaron las muestras 12 horas y se hicieron repicas a las 36 y 48 horas obteniendo resultados negativos para crecimiento de microorganismos en todos los casos…


Asunto(s)
Antibacterianos , Formaldehído , Esterilización , Instrumentos Dentales
18.
CES odontol ; 17(2): 57-57, jul.-dic. 2004.
Artículo en Español | LILACS | ID: lil-467239

RESUMEN

En la actualidad existen múltiples agentes para desinfección, que proporcionan disminución de cantidades apreciables de patógenos microbianos; el formaldehído (formalina) se utiliza frecuentemente como agente desinfectante sin estudios que soporten su uso o que garanticen los resultados esperados. En su forma natural el aldehído es un gas de bajo peso molecular, fácilmente diluible en agua y de dolor irritante característico; tiene gran tendencia a polimerizarse haciendo grupos de tres a cuatro moléculas obteniéndose el Trioximetanal o Para-formaldehído (formalina). Se realizo un estudio in vitro, simple ciego, con instrumental odontológico previamente contaminado con saliva de los pacientes que asistieron a diferentes procedimientos en la Clínica CES Sabaneta. Luego de utilizado el instrumental se lavó con jabón común, como normalmente se hace en la práctica clínica, para ser transportado en recipientes herméticos de 30 x 15 cm., de un libro de capacidad, los cuales contenían un rejilla plástica, separada 1 cm. de la base. Se anotó fecha, hora y número de muestra y se cerró herméticamente por 12 horas. Dentro de una cámara de flujo laminar, se realizó un frotis a cada una de las superficies de cada instrumento en forma independiente; se sembró en un caldo de cultivo BHI y en agar sangre para posteriormente incubar dicho frotis a 37 grados C por 24 y 48 horas. Se evaluaron 100 unidades instrumentales entre espejos, cucharillas, chorreadotes, bruñidores, pinzas, empacadores, elevadores, curetas, entre otros. En el grupo experimental se evaluaron 86 instrumentos y 14 en grupo control; en ninguno de ellos se observó crecimiento bacteriano aerobio, resultados que pueden sugerir una buena capacidad bactericida de la formalina con respecto a estos patógenos...


Asunto(s)
Antibacterianos , Instrumentos Dentales , Esterilización
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