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1.
Nutrients ; 15(12)2023 Jun 09.
Artículo en Inglés | MEDLINE | ID: mdl-37375594

RESUMEN

Despite the reported prevalence of micronutrient deficiencies in older adults, it is not yet established whether multivitamin/multimineral (MV/MM) supplements improve blood micronutrient status in individuals over the age of 65. Therefore, a cohort of 35 healthy men (>67 years) was recruited for an MV/MM supplementation trial. The primary endpoint was, as an indicator of micronutrient status, changes in blood micronutrient biomarkers from baseline to at least six months of supplementation with MV/MM or placebo. The secondary endpoint was basal O2 consumption in monocytes as an indicator of cellular metabolism. MV/MM supplementation improved blood concentrations of pyridoxal phosphate, calcifediol, α-tocopherol, and ß-carotene concentrations throughout the cohort. By contrast, those in the placebo group generally showed declines in blood vitamin concentrations and an increased prevalence of suboptimal vitamin status during the study period. On the other hand, MV/MM supplementation did not significantly affect blood mineral concentrations, i.e., calcium, copper, iron, magnesium, and zinc. Interestingly, MV/MM supplementation prevented the decline in monocyte O2 consumption rate. Overall, MV/MM use improves or prevents declines in vitamin, but not mineral, status and limits declines in cellular O2 consumption, which may have important implications for metabolism and immune health in healthy older men.


Asunto(s)
Oligoelementos , Vitaminas , Masculino , Humanos , Anciano , Suplementos Dietéticos , Minerales , Micronutrientes , Biomarcadores , Metabolismo Energético , Método Doble Ciego
2.
Arch Pharm Res ; 39(7): 946-52, 2016 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-27277165

RESUMEN

Response surface methodology (RSM) using a Box-Behnken design was used to optimize the extraction conditions for obtaining pancreatic lipase inhibitory and antioxidant principles from Ilex paraguariensis leaves. Three influencing factors: extraction time (min), the liquid-solid ratio, and ethanol concentration (%, v/v) were investigated in the ultrasonic extraction process. Optimization of the extraction conditions to obtain a product with minimum PL activity, maximum antioxidant activity, and maximum yield was performed using RSM by focusing on the three target influencing factors. The optimum conditions were established as the ethanol concentration (54.8 %), liquid-solid ratio (35.4), and extraction time (70.0 min). Under these conditions, the 2,2-diphenyl-1-picrylhydrazyl scavenging activity, PL activity, extraction yield were 59.3 ± 3.5, 35.3 ± 3.0, and 34.4 ± 0.4 %, respectively, similar to the theoretical predicted values of 59.7, 35.2, and 34.3 %, respectively.


Asunto(s)
Antioxidantes/análisis , Inhibidores Enzimáticos/análisis , Ilex paraguariensis , Lipasa/antagonistas & inhibidores , Páncreas/enzimología , Extractos Vegetales/análisis , Animales , Antioxidantes/farmacología , Química Farmacéutica/métodos , Inhibidores Enzimáticos/farmacología , Lipasa/metabolismo , Extractos Vegetales/farmacología , Hojas de la Planta , Porcinos
3.
Antimicrob Agents Chemother ; 60(5): 2972-80, 2016 05.
Artículo en Inglés | MEDLINE | ID: mdl-26953207

RESUMEN

To determine the distribution and relationship of antimicrobial resistance determinants among extended-spectrum-cephalosporin (ESC)-resistant or carbapenem-resistant Escherichia coli isolates from the aquatic environment in India, water samples were collected from rivers or sewage treatment plants in five Indian states. A total of 446 E. coli isolates were randomly obtained. Resistance to ESC and/or carbapenem was observed in 169 (37.9%) E. coli isolates, which were further analyzed. These isolates showed resistance to numerous antimicrobials; more than half of the isolates exhibited resistance to eight or more antimicrobials. The blaNDM gene was detected in 14/21 carbapenem-resistant E. coli isolates: blaNDM-1 in 2 isolates, blaNDM-5 in 7 isolates, and blaNDM-7 in 5 isolates. The blaCTX-M gene was detected in 112 isolates (66.3%): blaCTX-M-15 in 108 isolates and blaCTX-M-55 in 4 isolates. We extracted 49 plasmids from selected isolates, and their whole-genome sequences were determined. Fifty resistance genes were detected, and 11 different combinations of replicon types were observed among the 49 plasmids. The network analysis results suggested that the plasmids sharing replicon types tended to form a community, which is based on the predicted gene similarity among the plasmids. Four communities each containing from 4 to 17 plasmids were observed. Three of the four communities contained plasmids detected in different Indian states, suggesting that the interstate dissemination of ancestor plasmids has already occurred. Comparison of the DNA sequences of the blaNDM-positive plasmids detected in this study with known sequences of related plasmids suggested that various mutation events facilitated the evolution of the plasmids and that plasmids with similar genetic backgrounds have widely disseminated in India.


Asunto(s)
Antibacterianos/farmacología , Carbapenémicos/farmacología , Cefalosporinas/farmacología , Escherichia coli/efectos de los fármacos , Farmacorresistencia Bacteriana Múltiple/genética , Escherichia coli/metabolismo , India , Pruebas de Sensibilidad Microbiana , Plásmidos/genética , Ríos/microbiología , Aguas del Alcantarillado/microbiología , Purificación del Agua
4.
Disabil Rehabil ; 37(9): 790-4, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25060039

RESUMEN

PURPOSE: The purpose of this study was to examine the effects of 3 months of sitting Tai Chi training on the sitting balance control and eye-hand coordination of older adults subjects. METHODS: We randomly assigned 59 older adults from four residential care facilities to either sitting Tai Chi group or mobilizing exercises group as control. The sitting Tai Chi group underwent 3 months of training with a total of 36 sessions (1 hour/session, 3 sessions/week). The outcome measures included sitting balance tests (testing sequential weight shifting and forward reaching in a sitting position) and eye-hand coordination tests (reaction time, movement time and accuracy in finger pointing task). RESULTS: The Tai Chi practitioners showed significant improvement in their sequential weight shifting while sitting (improved by 29.0%, p ≤ 0.05) and in their maximum reaching distance from a sitting position (improved by 21.2%, p ≤ 0.05). No such improvements were found in the control group. In the eye-hand coordination test, the sitting Tai Chi practitioners had significant improvements in accuracy (improved by 17.3%, p ≤ 0.05). Also, no improvement was found in the control group. CONCLUSIONS: The results demonstrate 3-months of sitting Tai Chi training can improve sitting balance and accuracy in finger pointing task in the older adults. IMPLICATIONS FOR REHABILITATION: Traditional Tai Chi poses difficulties for older adults with poor standing balance. This pilot study showed that a 3 months sitting Tai Chi training can improve sitting balance and accuracy in the finger pointing task in the older adults. Sitting Tai Chi can be a therapy option for older adults with poor standing balance.


Asunto(s)
Terapia por Ejercicio/métodos , Dedos/fisiología , Destreza Motora , Equilibrio Postural/fisiología , Taichi Chuan/métodos , Anciano , Anciano de 80 o más Años , Envejecimiento , Femenino , Humanos , Masculino , Movimiento/fisiología , Proyectos Piloto , Tiempo de Reacción/fisiología , Resultado del Tratamiento
5.
Am J Phys Med Rehabil ; 92(7): 587-96, 2013 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-23291605

RESUMEN

OBJECTIVE: Chronic lateral epicondylosis is common, debilitating, and often refractory. Prolotherapy (PrT) is an injection therapy for tendinopathy. The efficacy of two PrT solutions for chronic lateral epicondylosis was evaluated. DESIGN: This study is a three-arm randomized controlled trial. Twenty-six adults (32 elbows) with chronic lateral epicondylosis for 3 mos or longer were randomized to ultrasound-guided PrT with dextrose solution, ultrasound-guided PrT with dextrose-morrhuate sodium solution, or watchful waiting ("wait and see"). The primary outcome was the Patient-Rated Tennis Elbow Evaluation (100 points) at 4, 8, and 16 wks (all groups) and at 32 wks (PrT groups). The secondary outcomes included pain-free grip strength and magnetic resonance imaging severity score. RESULTS: The participants receiving PrT with dextrose and PrT with dextrose-morrhuate reported improved Patient-Rated Tennis Elbow Evaluation composite and subscale scores at 4, 8, and/or 16 wks compared with those in the wait-and-see group (P < 0.05). At 16 wks, compared with baseline, the PrT with dextrose and PrT with dextrose-morrhuate groups reported improved composite Patient-Rated Tennis Elbow Evaluation scores by a mean (SE) of 18.7 (9.6; 41.1%) and 17.5 (11.6; 53.5%) points, respectively. The grip strength of the participants receiving PrT with dextrose exceeded that of the PrT with dextrose-morrhuate and the wait and see at 8 and 16 wks (P < 0.05). There were no differences in magnetic resonance imaging scores. Satisfaction was high; there were no adverse events. CONCLUSIONS: PrT resulted in safe, significant improvement of elbow pain and function compared with baseline status and follow-up data and the wait-and-see control group. This pilot study suggests the need for a definitive trial.


Asunto(s)
Solución Hipertónica de Glucosa/uso terapéutico , Calidad de Vida , Rango del Movimiento Articular/efectos de los fármacos , Morruato de Sodio/uso terapéutico , Codo de Tenista/tratamiento farmacológico , Adulto , Enfermedad Crónica , Quimioterapia Combinada , Femenino , Estudios de Seguimiento , Humanos , Inyecciones Intraarticulares , Masculino , Persona de Mediana Edad , Dimensión del Dolor , Proyectos Piloto , Rango del Movimiento Articular/fisiología , Valores de Referencia , Medición de Riesgo , Índice de Severidad de la Enfermedad , Método Simple Ciego , Codo de Tenista/diagnóstico por imagen , Resultado del Tratamiento , Ultrasonografía Doppler
7.
Pharm Biol ; 49(5): 464-70, 2011 May.
Artículo en Inglés | MEDLINE | ID: mdl-21281250

RESUMEN

CONTEXT: Vernonia amygdalina Del. (VA; Asteraceae or Compositae) is a small tree growing throughout tropical Africa. It is widely used for food and medicinal purposes by local people. It was reported that it had several qualities, including anticancer activity. OBJECTIVE: A sesquiterpene lactone, vernodalinol, was isolated from VA leaves. The first reported source of vernodalinol was in 2009 from a different plant, only (1)H NMR spectrum and no detailed structural analysis were carried out. No whole spectroscopic data were provided. MATERIALS AND METHODS: VA dried leaves were extracted with 85% ethanol followed by further separation into four fractions by liquid-liquid extraction technique using various solvents: hexane, chloroform, and n-butanol. Vernodalinol was separated from the n-butanol fraction by column chromatography. The biological activity of vernodalinol was evaluated in estrogen receptor-positive (ER(+)) human breast carcinoma cells (MCF-7) in vitro. RESULTS: Results indicated that vernodalinol (25 and 50 µg/mL) inhibited breast cancerous cell growth (DNA synthesis) by 34% (P < 0.025) and 40% (P < 0.025), respectively. It is reasonable to expect an LC(50) of 70-75 µg/mL for vernodalinol in MCF-7 cells. DISCUSSION AND CONCLUSION: Vernodalinol structure was confirmed using a battery of spectroscopic methods, 1D and 2D NMR, high-resolution mass spectrometry (HR-MS), UV, IR, and X-ray. These results suggest that vernodalinol, although it has some biological activity, is likely to work in concert with other ingredients responsible for the anticancer activity exhibited of VA.


Asunto(s)
Extractos Vegetales/análisis , Sesquiterpenos/aislamiento & purificación , Vernonia/química , Línea Celular Tumoral , Cristalografía por Rayos X , ADN/biosíntesis , Humanos , Sesquiterpenos/química , Sesquiterpenos/farmacología
8.
Clin Toxicol (Phila) ; 49(1): 34-9, 2011 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-21114414

RESUMEN

OBJECTIVE: To evaluate an algorithmic approach involving a multidisciplinary team for causality assessment of suspected herb-induced liver injury (HILI) cases and to compare the causality score using this multidisciplinary approach and Roussel Uclaf Causality Assessment Method (RUCAM). METHODS: A team consisting of hepatologist, clinical toxicologist, analytical toxicologist, and Chinese medicine (CM) pharmacist was formed to do causality assessment based on a protocol for suspected HILI cases. The likelihood of the diagnosis of individual case was first assessed systematically by a hepatologist and clinical toxicologist independently after collecting information about four aspects: (1) clinical course, (2) exclusion of alternative causes, (3) quality of the prescription and herbal product by examining the CM prescriptions and analysis of biological and herb samples, (4) scientific support on comprehensive literature review on English and Chinese medical database, and subsequently concluded in a consensus meeting held by the multidisciplinary team. The final causality score of each patient was compared with the likelihood of causality as assessed by RUCAM. RESULTS: Between 2005 and 2007, 48 consecutive patients with suspected HILI were enrolled and 21 patients were excluded due to the establishment of an alternative cause of liver impairment or the lack of any information on the herbs taken. Twenty-seven patients were recruited, among them 15 consumed Chinese herbal medicines, 10 used proprietary Chinese medicinal products, and 2 used both. The concordance between the causality assessment of the hepatologist and clinical toxicologist was moderate (weighted κ = 0.48, 95%CI 0.30-0.66). The causality assessment process concluded that the likelihood of HILI was "highly probable" in 5 cases and "probable" in 12, whereas there were 5 "highly probable" and 16 "probable" cases as assessed by RUCAM. The causality assessment by the multidisciplinary approach and RUCAM also showed moderate agreement (weighted κ= 0.51, 95%CI 0.22-0.81). CONCLUSION: A multidisciplinary approach using defined algorithms is a scientific approach in causality assessment for HILI. Further study is needed to assess its accuracy and applicability.


Asunto(s)
Enfermedad Hepática Inducida por Sustancias y Drogas/etiología , Medicamentos Herbarios Chinos/envenenamiento , Medición de Riesgo , Adulto , Anciano , Algoritmos , Femenino , Humanos , Masculino , Persona de Mediana Edad
9.
Exp Biol Med (Maywood) ; 235(12): 1472-8, 2010 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-20962014

RESUMEN

Vernonia amygdalina (VA) is widely used for medicinal and food purposes in tropical Africa. Many health benefits (antioxidant, antimicrobial, anticancer activities and more) of VA extracts have been reported. The mechanisms of actions have also been described. We have previously reported that VA extracts elicited growth inhibitory activities in human estrogen receptor-positive (ER(+)) cells (MCF-7 cells) and ductal carcinoma cells (BT-549) in vitro. The active components in the organic solvent (chloroform)-extracted VA have been previously determined. However, the active components in the ethanolic extracts of VA have not been previously studied. Hence, the objectives of this study are to isolate and characterize the active components of the ethanolic extracts of VA using liquid-liquid extraction, thin layer chromatography and column techniques. Fractionation of the ethanolic extracts of VA yielded three fractions named A1, A2 and A3, and A2 retained the DNA synthesis-inhibitory activity of the extracts. Subsequent fractionation of A2 yielded fraction A2B whose activity was 16 and three times more potent than the ethanolic fraction and fraction A2, respectively. The treatment of cells with 100 µg/mL of either the ethanolic VA extracts, fraction A2 or fraction A2B resulted in a 23% (P < 0.01), 86% (P < 0.0001) and 97% (P < 0.0001) inhibition of DNA synthesis compared with vehicle-treated controls, respectively. Further purification of A2B by high-speed countercurrent chromatography and confirmed by spectroscopic analysis revealed that the major active components of A2B (65% by weight) were steroid glucosides.


Asunto(s)
Antineoplásicos Fitogénicos/química , Neoplasias de la Mama/tratamiento farmacológico , Carcinoma/tratamiento farmacológico , Proliferación Celular/efectos de los fármacos , Extractos Vegetales/química , Vernonia/química , Animales , Antineoplásicos Fitogénicos/aislamiento & purificación , Antineoplásicos Fitogénicos/uso terapéutico , Línea Celular Tumoral , Fraccionamiento Químico , Cromatografía en Capa Delgada , ADN/biosíntesis , Replicación del ADN/efectos de los fármacos , Femenino , Humanos , Extractos Vegetales/aislamiento & purificación , Extractos Vegetales/uso terapéutico
10.
J Food Sci ; 75(8): E522-6, 2010 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-21535491

RESUMEN

About 1.2 billion pounds of peanut butter are consumed annually in the United States. In 2008 to 2009, an outbreak involving Salmonella Typhimurium in peanut butter led to a recall of over 3900 products by over 200 companies. More than 700 people became sick, 100 were hospitalized, and 9 people died from this outbreak. This study examines the efficacy of high-pressure processing (HPP) to decrease S. Typhimurium American Type Culture Collection (ATCC) 53647 inoculated into peanut butter and model systems. The viability of S. Typhimurium in peanut butter stored at room temperature was investigated. A culture of S. Typhimurium (6.88 log CFU/g) was inoculated into peanut butter. Following 28 d at 20 °C there was a 1.23-log reduction. Approximately 10(6) to 10(7) CFU/g S. Typhimurium were inoculated into 4 brands of peanut butter, 3 natural peanut butters and peanut flour slurries at 2, 5, and 10% peanut flour protein in peanut oil and in distilled water. All were treated at 600 MPa for 5 min at 45 °C. While significant differences were found between natural peanut butter and peanut protein mixtures, the reduction was <1.0 log. The peanut flour/oil mixtures had a 1.7, 1.6, and 1.0-log reduction from HPP (2, 5, and 10% protein, respectively) whereas peanut flour/water mixtures had a 6.7-log reduction for all protein levels. Oil had a protective effect indicating HPP may not help the microbial safety of water-in-oil food emulsions including peanut butter. Practical Application: There have been multiple outbreaks of foodborne illness involving peanut butter products. This study looks at the potential use of high-pressure processing to reduce the bacteria that may be in peanut butter.


Asunto(s)
Arachis/microbiología , Condimentos/microbiología , Conservación de Alimentos/métodos , Salmonella typhimurium/crecimiento & desarrollo , Semillas/microbiología , Arachis/química , Fenómenos Químicos , Recuento de Colonia Microbiana , Proteínas en la Dieta/análisis , Comida Rápida/microbiología , Estudios de Factibilidad , Manipulación de Alimentos , Viabilidad Microbiana , Modelos Biológicos , Aceite de Cacahuete , Aceites de Plantas/análisis , Aceites de Plantas/química , Proteínas de Plantas/análisis , Proteínas de Plantas/química , Presión , Intoxicación Alimentaria por Salmonella/prevención & control , Semillas/química , Factores de Tiempo
11.
Exp Biol Med (Maywood) ; 234(4): 410-7, 2009 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-19176872

RESUMEN

Vernonia amygdalina (VA) is an edible plant of the Asteraceae family used in many herbal formulations prescribed by herbalists for many diseases. We have previously reported that aqueous VA extracts inhibit the growth of estrogen receptor-positive human breast cancerous cells in vitro. Activity markers of the VA extracts have not been previously identified or characterized. Hence, the objective of this study was to identify activity markers of the VA extracts associated with cell growth inhibition. Extraction of VA with multiple solvents of various polarity indexes yielded three fractions (A-1-2, B-1-3) that significantly inhibited cell growth (P < 0.05) at 0.1 mg/ml concentration. At a higher concentration of 1 mg/ml, six fractions of hexane, chloroform, butanol, and ethyl acetate (A-1-3, B-1-4) inhibited DNA synthesis by 76%, 98%, 94%, 98%, 98%, and 96%, respectively. These fractions were UV-detected from 250-730 nm; and all showed three distinct peaks around 410, 431, and 664 nm. Furthermore, HPLC analysis of the fractions revealed similar retention times of 2.213, 2.167, and 2.151 min, respectively. Bioactivity assays showed that HPLC retention of approximately 2 min is required for cell growth-inhibitory activity of VA fractions. Interestingly, all active fractions exhibited HPLC peaks at approximately 2 min. Therefore, the UV and HPLC peaks may be used as predictive tools to determine VA extracts activities.


Asunto(s)
Antineoplásicos Fitogénicos/farmacología , Neoplasias de la Mama/tratamiento farmacológico , Carcinoma/tratamiento farmacológico , Proliferación Celular/efectos de los fármacos , Extractos Vegetales/farmacología , Vernonia/química , Antineoplásicos Fitogénicos/química , Neoplasias de la Mama/patología , Carcinoma/patología , Línea Celular Tumoral , Fraccionamiento Químico , Cromatografía Líquida de Alta Presión , Humanos , Extractos Vegetales/química
12.
Semin Cutan Med Surg ; 26(1): 15-21, 2007 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-17349558

RESUMEN

Medical and esthetic indications and demand for nonablative laser and light-based treatments are increasing. Although these are generally safe procedures, laser practitioners should be aware of potential complications that may be associated with therapy. An adverse event may be defined as any undesirable effect, even if expected, that occurs with laser treatment. These adverse events can be related to patient factors, professional errors, common side effects, and more serious complications. A variety of providers, including nondermatologists, perform laser treatments and must be aware of therapeutic outcomes as well as potential complications after laser surgery. Clinical indications for nonablative laser treatments, common side effects, and more serious adverse events will be reviewed in addition to treatment and prevention of these potential complications.


Asunto(s)
Dermatología/instrumentación , Rayos Láser/efectos adversos , Fototerapia/efectos adversos , Enfermedades de la Piel/terapia , Falla de Equipo , Humanos , Errores Médicos
13.
J Reprod Med ; 52(1): 53-8, 2007 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-17286070

RESUMEN

OBJECTIVE: To evaluate the results of KTP-Nd:YAG laser therapy for the treatment of vestibulodynia. STUDY DESIGN: Retrospective review and follow-up mail survey of women with vestibulodynia who underwent laser treatment. Demographics, number of laser treatments and symptom severity prior to laser treatment (100-mm visual analog scale) were obtained from the medical record. The survey included questions regarding current sexual pain, sexual quality of life and satisfaction with treatment. RESULTS: Of41 treated women, 37 women were located and agreed to participate. The mean number of laser sessions was 2.81 (range, 1-8). The mean age was 32.9 years and mean follow-up, 2.8. Following laser treatment, most (24 of 37, 68%) subjects reported less pain with sexual intercourse. One subject reported more pain, while 29% (11 of 37) reported no change. Sixty percent (21 of 37) reported their sex lives to be more satisfying/pleasurable following laser treatment. Thirteen women (13 of 37, 35%) underwent vestibulectomy following laser therapy, and 2 subjects were treated with a laser after failed vestibulectomy. CONCLUSION: Most women with vestibulodynia treated with a KTP-Nd:YAG laser achieve a reduction in sexual pain and improved sexual satisfaction without excisional therapy.


Asunto(s)
Terapia por Luz de Baja Intensidad , Manejo del Dolor , Enfermedades de la Vulva/terapia , Adulto , Dispareunia/terapia , Femenino , Estudios de Seguimiento , Humanos , Persona de Mediana Edad , Dolor/complicaciones , Dolor/psicología , Estudios Retrospectivos , Enfermedades de la Vulva/complicaciones , Enfermedades de la Vulva/psicología
14.
Ecotoxicol Environ Saf ; 59(3): 300-8, 2004 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-15388269

RESUMEN

The use of oil dispersants is a controversial countermeasure in the effort to minimize the impact of oil spills. The risk of ecological effects will depend on whether oil dispersion increases or decreases the exposure of aquatic species to the toxic components of oil. To evaluate whether fish would be exposed to more polycyclic aromatic hydrocarbon (PAH) in dispersed oil relative to equivalent amounts of the water-accommodated fraction (WAF), measurements were made of CYP1A induction in trout exposed to the dispersant (Corexit 9500), WAFs, and the chemically enhanced WAF (dispersant; CEWAF) of three crude oils. The crude oils comprised the higher viscosity Mesa and Terra Nova and the less viscous Scotian Light. Total petroleum hydrocarbon and PAH concentrations in the test media were determined to relate the observed CYP1A induction in trout to dissolved fractions of the crude oil. CYP1A induction was 6- to 1100-fold higher in CEWAF treatments than in WAF treatments, with Terra Nova having the greatest increase, followed by Mesa and Scotian Light. Mesa had the highest induction potential with the lowest EC50 values for both WAF and CEWAF. The dispersant Corexit was not an inducer and it did not appear to affect the permeability of the gill surface to known inducers such as beta-napthoflavone. These experiments suggest that the use of oil dispersants will increase the exposure of fish to hydrocarbons in crude oil.


Asunto(s)
Exposición a Riesgos Ambientales , Lípidos/química , Petróleo , Hidrocarburos Policíclicos Aromáticos/farmacocinética , Animales , Branquias , Oncorhynchus mykiss , Permeabilidad , Contaminación del Agua/prevención & control
15.
Environ Toxicol ; 19(4): 267-73, 2004 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-15269895

RESUMEN

The performance of four microscale toxicity bioassays conducted on whole sediments was evaluated during a bioremediation project undertaken in 1999-2000 on a crude oil-contaminated freshwater shoreline of the St. Lawrence River, Quebec, Canada. The toxicity tests assessed included: (1) the Microtox solid-phase assay (MSPT), (2) the Biotox Flash solid-phase test (Flash), (3) the algal solid-phase assay (ASPA), and 4) the Ostracodtoxkit solid-phase assay. Data generated with these assays were compared with those obtained using the standard endobenthic amphipod (Hyalella azteca) bioassay. Bioanalytical comparisons indicated that all five solid-phase tests were useful in detecting the toxicity of oiled sediments; however, statistical analyses distinguished a difference in response between the invertebrate (amphipod and Ostracodtoxkit) and bacterial luminescence tests (MSPT and Flash). Based on these results, it is recommended that careful selection of biotests be made in the design of the test battery for assessment of residual oil sediment toxicity. Time-series toxicity data generated with ASPA indicated that oiled sediments in the freshwater wetlands of the St. Lawrence River remained toxic to phytoplankton for at least 65 weeks and that remediation treatment was able to accelerate detoxification by 16 weeks.


Asunto(s)
Sedimentos Geológicos , Petróleo/toxicidad , Contaminantes Químicos del Agua/toxicidad , Anfípodos/efectos de los fármacos , Animales , Biodegradación Ambiental , Bioensayo/métodos , Bioensayo/estadística & datos numéricos , Chlorophyta/efectos de los fármacos , Chlorophyta/enzimología , Crustáceos/efectos de los fármacos , Agua Dulce/análisis , Sedimentos Geológicos/análisis , Mediciones Luminiscentes , Fitoplancton , Quebec , Reproducibilidad de los Resultados , Ríos , Factores de Tiempo , Vibrio/metabolismo
16.
Environ Toxicol ; 19(4): 329-35, 2004 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-15269903

RESUMEN

Phytoremediation in a simulated crude oil spill was studied with a "minimalistic" approach. The SPMD-TOX paradigm-a miniature passive sorptive device to collect and concentrate chemicals and microscale tests to detect toxicity-was used to monitor over time the bioavailability and potential toxicity of an oil spill. A simulated crude oil spill was initiated on an intertidal freshwater grass-wetland along the St. Lawrence River southwest of Quebec City, Quebec, Canada. Several phytoremediation treatments were investigated; to dissipate and ameliorate the spill, treatments included nutrient amendments with inorganic nitrogen sources (ammonium nitrate and sodium nitrate) and phosphate (super triple phosphate) with and without cut plants, with natural attenuation (no phytoremedial treatment) as a control. Sequestered oil residues were bioavailable in all oil-treated plots in Weeks 1 and 2. Interestingly, the samples were colored and fluoresced under ultraviolet light. In addition, microscale tests showed that sequestered residues were acutely toxic and genotoxic, as well as that they induced hepatic P(450) enzymes. Analysis of these data suggested that polycyclic aromatic hydrocarbons were among the bioavailable residues sequestered. In addition, these findings suggested that the toxic bioavailable fractions of the oil spill and degradation products dissipated rapidly over time because after the second week the water column contained no oil or detectable degradation products in this riverine intertidal wetland. SPMD-TOX revealed no evidence of bioavailable oil products in Weeks 4, 6, 8, and 12. All phytoremediation efforts appeared to be ineffective in changing either the dissipation rate or the ability to ameliorate the oil toxicity. SPMD-TOX analysis of the water columns from these riverine experimental plots profiled the occurrence, dissipation, and influence of phytoremediation on the bioavailability and toxicity of oil products (parent or degradation products).


Asunto(s)
Petróleo/toxicidad , Pruebas de Toxicidad/métodos , Contaminantes Químicos del Agua/toxicidad , Animales , Biodegradación Ambiental , Disponibilidad Biológica , Cyperaceae/metabolismo , Citocromo P-450 CYP1A1/biosíntesis , Monitoreo del Ambiente/métodos , Colorantes Fluorescentes , Sedimentos Geológicos/química , Ictaluridae/metabolismo , Mediciones Luminiscentes , Membranas Artificiales , Pruebas de Mutagenicidad , Petróleo/metabolismo , Quebec , Ríos , Factores de Tiempo , Pruebas de Toxicidad/instrumentación , Rayos Ultravioleta , Vibrio/genética , Vibrio/metabolismo , Movimientos del Agua , Contaminantes Químicos del Agua/metabolismo
17.
J Food Prot ; 48(4): 355-358, 1985 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-30943607

RESUMEN

The bioavailability of zinc and copper from meats cured with erythorbate and/or nitrite was evaluated. Iron-depleted rats were fed six test diets that contained as protein sources: uncured meat, meat cured with erythorbate, meat cured with nitrite, meat cured with nitrite and erythorbate, lactalbumin, and lactalbumin supplemented with iron to the levels present in the meat-based diets. All diets contained similar levels of zinc and copper. Treatment of the meat with usual commercial levels of nitrite (156 µg/g meat) and/or erythorbate (550 µg/g meat) had no significant effect on zinc and copper utilization by rats. However, rats fed meat-based diets retained more zinc and copper in their livers than rats fed lactalbumin-based diets.

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