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2.
Environ Monit Assess ; 191(9): 565, 2019 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-31414303

RESUMEN

This research compared the effects of biosurfactant on the biodegradation of biodiesel and vegetable oils while validating two conceptually diverging methodologies. The two experimental setups were successfully modeled towards the effects of biosurfactants during biodegradation. We established the equivalence of both methodologies from the data output. As expected, the biosurfactants caused an increased oil uptake, thus increasing biodegradation performance. Cooking oils were favored by the microbial consortium as a carbon source when compared with biodiesel fuel, especially after use in food preparation. However, we found that biodiesel substrate standout with the highest biodegradation rates. Our results might indicate that a rapid metabolic change from the original compound initially favored biodiesels during the assimilation of organic carbon for a set specialized microbial inoculum. The data output was successfully combined with mathematical models and statistical tools to describe and predict the actual environmental behavior of biodiesel and vegetable oils. The models confirmed and predicted the biodegradation effectiveness with biosurfactants and estimated the required timeframe to achieve satisfactory contaminant removal.


Asunto(s)
Biodegradación Ambiental , Biocombustibles/análisis , Monitoreo del Ambiente/métodos , Consorcios Microbianos/fisiología , Aceites de Plantas/análisis , Tensoactivos/química , Carbono , Aceites de Plantas/metabolismo , Verduras/metabolismo
3.
Artículo en Inglés | MEDLINE | ID: mdl-26921015

RESUMEN

Diabetes mellitus (DM) is characterized by high blood glucose. Excessive production of free radicals may cause oxidative damage to DNA and other molecules, leading to complications of the disease. It may be possible to delay or reduce such damage by administration of antioxidants such as folic acid (FA). The objective of this study was to determine the effect of FA on nuclear abnormalities (NAs) in the oral mucosa of patients with DM. NAs (micronucleated cells, binucleated cells, pyknotic nuclei, karyorrhexis, karyolysis, abnormally condensed chromatin, and nuclear buds) were analyzed in 2000 cells from 45 healthy individuals (control group) and 55 patients with controlled or uncontrolled type I or II DM; 35 patients in the latter group were treated with FA. Samples were taken from the FA group before and after treatment. An increased rate of NAs was found in patients with DM in comparison with that of the control group (P<0.001). FA supplementation in patients with DM reduced the frequency of NAs (20.4 ± 8.0 before treatment vs. 10.5 ± 5.2 after treatment; P<0.001). The type I and type II DM and controlled and uncontrolled DM subgroups were analyzed in terms of sex, age, and smoking habit. The significantly reduced frequencies of buccal mucosa cells with micronuclei, binucleation, pyknosis, karyorrhexis, karyorrhexis+abnormally condensed chromatin, karyolysis, and nuclear buds produced by FA supplementation in DM patients (P<0.02) are consistent with the idea that free radicals are responsible for the increased frequency of NAs in DM patients.


Asunto(s)
Núcleo Celular/efectos de los fármacos , Diabetes Mellitus Tipo 1/tratamiento farmacológico , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Ácido Fólico/uso terapéutico , Micronúcleos con Defecto Cromosómico , Mucosa Bucal/anomalías , Mucosa Bucal/efectos de los fármacos , Adulto , Estudios de Casos y Controles , Núcleo Celular/metabolismo , Suplementos Dietéticos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Mucosa Bucal/citología , Adulto Joven
4.
Bioprocess Biosyst Eng ; 38(9): 1629-37, 2015 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-25911424

RESUMEN

In this work, the optimization of the operational conditions for the chloroform-based extraction of surface-active compounds from corn steep liquor (CSL) was carried out and the nutritional properties of the remnant aqueous phase (CSL-less biosurfactant) was evaluated as microbial fermentation medium. The optimal conditions to obtain biosurfactants from CSL were as follows: chloroform/CSL ratio 2 (v/v), 56 °C at extraction times >30 min. At the optima conditions, 100 % of biosurfactant extract can be obtained from CSL, obtaining 12.0 ± 0.5 g of biosurfactant extract/Kg of CSL. The critical micelle concentration (CMC) of the biosurfactant extract was 399.4 mg L(-1). This value is similar to the CMC of cetrimonium bromide (CTAB), a cationic surfactant used in the formulation of nanoparticles. The extraction of biosurfactant can be also carried out at room temperature although in this case, the extraction yield decreased about 15 %. The extraction of surface-active compounds from agroindustrial streams can suppose important advances for the bio-based surfactants industry. Biosurfactants obtained in this work are not only more eco-friendly than chemical detergents but also can be cost competitive with its chemical counterparts. Furthermore, after the extraction of surface-active compounds, CSL-less biosurfactant was found to be suitable as nutritional supplement for lactic acid bacteria, maintaining its nutritional properties in comparison with regular CSL.


Asunto(s)
Cloroformo/química , Extracción Líquido-Líquido/métodos , Extractos Vegetales/química , Extractos Vegetales/aislamiento & purificación , Tensoactivos/aislamiento & purificación , Zea mays/química , Productos Biológicos/química , Productos Biológicos/aislamiento & purificación , Tecnología Química Verde , Interacciones Hidrofóbicas e Hidrofílicas , Residuos Industriales/prevención & control , Tensoactivos/química
5.
J Agric Food Chem ; 49(5): 2459-64, 2001 May.
Artículo en Inglés | MEDLINE | ID: mdl-11368620

RESUMEN

The antioxidant and antimicrobial activities of ethyl acetate extracts obtained from acid hydrolysates of several lignocellulosic materials (Eucalyptus globulus wood, barley bran, corn cobs, and corn leaves) were evaluated. The minimum inhibitory and bactericide concentrations (MIC and MBC, respectively) were determined against a selection of bacteria and yeasts. Extracts from Eucalyptus wood hydrolysates were the most active for inhibiting bacteria and yeast growth, with MIC in the range of 10(2)--5 x 10(3) microg/mL and MBC in the range of 10(3)--0(5) microg/mL. Bacteriogenic and bacteriostatic activities of extracts from Eucalyptus wood and barley bran acid hydrolysates were slightly higher than those of corn cobs and leaves. Both the radical scavenging capacity and the inhibition of the beta-carotene bleaching caused by extracts were determined and compared with those of synthetic antioxidants. The antioxidant activity of extracts increased with their concentrations in the media, the stronger properties corresponding to those obtained from Eucalyptus wood hydrolysates.


Asunto(s)
Acetatos/farmacología , Celulosa/química , Lignina/química , Extractos Vegetales/farmacología , Antioxidantes , Bacterias/efectos de los fármacos , Hidrólisis , Pruebas de Sensibilidad Microbiana , Factores de Tiempo , Levaduras/efectos de los fármacos
6.
Dermatol Surg ; 21(7): 649-51, 1995 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-7606381

RESUMEN

BACKGROUND: Pain and needle-phobia can be a problem during the application of local anesthesia with syringe and needle. OBJECTIVE: To evaluate a jet-injection device (without needle) to deliver local anesthesia. METHODS: Two hundred and six minor dermatological procedures using a jet-injection device for administering local anesthesia into skin tissue were performed. We comment on the technical procedures, application, usefulness in relation to areas involved and the anatomical location of lesion, and total dosage of the anesthetic agent. RESULTS: Total absence of pain during installation of anesthetic (N = 194; 94%). Good level of anesthesia in all patients. No local adverse effects. CONCLUSION: The jet-injection device is easy to handle, it is harmless, it provides good levels of anesthesia, and the dosage of anesthetic agent is smaller than the dosage administered with conventional methods.


Asunto(s)
Anestesia Local/instrumentación , Procedimientos Quirúrgicos Dermatologicos , Inyecciones a Chorro/instrumentación , Procedimientos Quirúrgicos Ambulatorios , Anestesia Local/métodos , Diseño de Equipo , Humanos , Inyecciones a Chorro/métodos , Mepivacaína/administración & dosificación , Procedimientos Quirúrgicos Menores , Dolor/prevención & control , Piel/patología , Enfermedades de la Piel/cirugía , Neoplasias Cutáneas/cirugía , Factores de Tiempo
7.
An Esp Pediatr ; 38(1): 17-9, 1993 Jan.
Artículo en Español | MEDLINE | ID: mdl-8439072

RESUMEN

We report the results of 100 cases of acute intussusception treated by inflation of the colon with air under controlled pressure. We compare this method with the traditional one and we analyse the advantages of each method. Successful reduction was achieved in 76% of the cases of intussusception treated with a barium enema and in 88% of the cases treated with an air enema. Pneumocolon in the treatment of acute intestinal intussusception is an alternative method that is very effective and with additional advantages such as: less radiation, less cost and less morbidity in case of perforation.


Asunto(s)
Aire , Intususcepción/diagnóstico por imagen , Presión , Sulfato de Bario/uso terapéutico , Enema , Femenino , Humanos , Lactante , Intususcepción/terapia , Masculino , Neumorradiografía
8.
Am J Med ; 93(2): 123-30, 1992 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-1497007

RESUMEN

PURPOSE: The administration of amphotericin B in the conventional prolonged infusion over 4 to 6 hours is complicated by the acute toxicities of fevers and chills in 50% to 90% of patients and the chronic toxicities of increased creatinine levels and hypokalemia in 60% to 80% of patients. To determine the safety and toxicity of rapid infusions, we conducted a prospective, nonrandomized study in patients with clinical indications for antifungal therapy. PATIENTS AND METHODS: Twenty-five granulocytopenic adults with acute leukemia and myelodysplastic syndromes were enrolled in a phase I trial using four sequentially shorter infusion durations: a standard infusion over 4 hours (n = 3) and shortened infusion durations at 3 hours (n = 3), 2 hours (n = 4), and 1 hour (n = 15). Toxicity was assessed by daily examinations of study subjects by one of the study investigators, by documentation of all infusion-related fevers and chills, and by daily monitoring of serum levels of creatinine, potassium, magnesium, and aspartate aminotransferase. RESULTS: Temperatures greater than 38 degrees C occurred in 16 of 25 (64%) patients, but only two had temperatures exceeding 40 degrees C. Chills were observed in 13 of 25 (56%) patients, but only one had severe symptoms. Serum creatinine increased more than 0.5 mg/dL (44.20 mumol/L) above the pretreatment baseline in 17 of 25 (68%) patients, and the absolute creatinine level was greater than or equal to 2.0 mg/dL (176.8 mumol/L) in 10 of 25 (40%) patients. Serum potassium levels dropped below the normal limit of 3.5 mEq/L (3.5 mmol/L) in all patients, but no patient had potassium levels below 2.5 mEq/L (2.5 mmol/L). Intravenous potassium supplementation was administered to all patients and exceeded 100 mEq/d in 12 of 25 (48%) patients. CONCLUSIONS: Rapid infusions of amphotericin B are safe, are associated with similar toxicity as prolonged infusions, and facilitate inpatient care by decreasing nursing time needed for administration and minimizing scheduling conflicts with other necessary intravenous medications. Shorter infusions also facilitate outpatient and home administration of amphotericin B.


Asunto(s)
Anfotericina B/administración & dosificación , Anfotericina B/efectos adversos , Anciano , Médula Ósea/efectos de los fármacos , Enfermedad Hepática Inducida por Sustancias y Drogas , Evaluación de Medicamentos , Femenino , Fiebre/inducido químicamente , Humanos , Hipopotasemia/inducido químicamente , Infusiones Intravenosas , Enfermedades Renales/inducido químicamente , Magnesio/sangre , Masculino , Persona de Mediana Edad , Proyectos Piloto , Estudios Prospectivos , Factores de Tiempo , Resultado del Tratamiento
9.
J Neurooncol ; 2(3): 219-22, 1984.
Artículo en Inglés | MEDLINE | ID: mdl-6150069

RESUMEN

In a murine model system, glutamic acid has demonstrated host protective properties during administration of vincristine (VCR). Subsequently, glutamic acid has been evaluated in patients receiving VCR during adjuvant chemotherapy for stage II carcinoma of the breast. The cumulative VCR dosage and toxicities incurred in 16 patients receiving glutamic acid have been compared to those observed in 88 patients who previously received VCR without glutamic acid in the same chemotherapy program. All patients received VCR 1.0 mg/m2 weekly for 6 weeks with dose modification for neurotoxicity. Treatment patients received glutamic acid 1.5 grams p.o. daily in three divided doses during the induction course. Of the 16 treatment patients, 9 (56%) received 100% ideal dosage of VCR during induction therapy whereas only 24 of 88 (27%) comparison patients attained this dosage level (p less than .025). Gastrointestinal and hematologic toxicities were similar in both groups. These preliminary results suggest the need for an expanded trial of this agent during administration of VCR.


Asunto(s)
Neoplasias de la Mama/tratamiento farmacológico , Glutamatos/uso terapéutico , Enfermedades del Sistema Nervioso/inducido químicamente , Vincristina/uso terapéutico , Protocolos de Quimioterapia Combinada Antineoplásica , Quimioterapia Combinada , Femenino , Ácido Glutámico , Humanos , Enfermedades del Sistema Nervioso/prevención & control , Vincristina/efectos adversos , Vincristina/antagonistas & inhibidores
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