RESUMEN
Soil microorganisms are key contributors to nutrient cycling and are essential for the maintenance of healthy soils and sustainable agriculture. Although the antimicrobial effects of a broad range of nanoparticulate substances have been characterised in vitro, little is known about the impact of these compounds on microbial communities in environments such as soil. In this study, the effect of three widely used nanoparticulates (silver, silicon dioxide and aluminium oxide) on bacterial and fungal communities in an agricultural pastureland soil was examined in a microcosm-based experiment using a combination of enzyme analysis, molecular fingerprinting and amplicon sequencing. A relatively low concentration of silver nanoparticles (AgNPs) significantly reduced total soil dehydrogenase and urease activity, while Al2O3 and SiO2 nanoparticles had no effect. Amplicon sequencing revealed substantial shifts in bacterial community composition in soils amended with AgNPs, with significant decreases in the relative abundance of Acidobacteria and Verrucomicrobia and an increase in Proteobacteria. In particular, the relative abundance of the Proteobacterial genus Dyella significantly increased in AgNP amended soil. The effects of Al2O3 and SiO2 NPs on bacterial community composition were less pronounced. AgNPs significantly reduced bacterial and archaeal amoA gene abundance in soil, with the archaea more susceptible than bacteria. AgNPs also significantly impacted soil fungal community structure, while Al2O3 and SiO2 NPs had no effect. Several fungal ribotypes increased in soil amended with AgNPs, compared to control soil. This study highlights the need to consider the effects of individual nanoparticles on soil microbial communities when assessing their environmental impact.
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Óxido de Aluminio/toxicidad , Nanopartículas/toxicidad , Dióxido de Silicio/toxicidad , Plata/toxicidad , Microbiología del Suelo , Contaminantes del Suelo/toxicidad , Agricultura , Medición de Riesgo , Suelo/químicaRESUMEN
Commercial cultivation of the button mushroom Agaricus bisporus is performed through the inoculation of a semipasteurized composted material. Pasteurization of the compost material prior to inoculation results in a substrate with a fungal community that becomes dominated by A. bisporus. However, little is known about the composition and activity in the wider fungal community beyond the presence of A. bisporus in compost throughout the mushroom cropping process. In this study, the fungal cropping compost community was characterized by sequencing nuc rDNA ITS1-5.8S-ITS2 amplified from extractable DNA and RNA. The fungal community generated from DNA extracts identified a diverse community containing 211 unique species, although only 51 were identified from cDNA. Agaricus bisporus was found to dominate in the DNA-derived fungal community for the duration of the cropping process. However, analysis of cDNA extracts found A. bisporus to dominate only up to the first crop flush, after which activity decreased sharply and a much broader fungal community became active. This study has highlighted the diverse fungal community that is present in mushroom compost during cropping.
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Agaricus/crecimiento & desarrollo , Biota , Compostaje , Hongos/clasificación , Hongos/genética , Variación Genética , Análisis por Conglomerados , ADN Complementario/química , ADN Complementario/genética , ADN de Hongos/química , ADN de Hongos/genética , ADN Espaciador Ribosómico/química , ADN Espaciador Ribosómico/genética , Filogenia , ARN Ribosómico 5.8S/genética , Análisis de Secuencia de ADNRESUMEN
BACKGROUND: Myelodysplastic syndromes are a diverse and common group of chronic hematologic cancers. The identification of new genetic lesions could facilitate new diagnostic and therapeutic strategies. METHODS: We used massively parallel sequencing technology to identify somatically acquired point mutations across all protein-coding exons in the genome in 9 patients with low-grade myelodysplasia. Targeted resequencing of the gene encoding RNA splicing factor 3B, subunit 1 (SF3B1), was also performed in a cohort of 2087 patients with myeloid or other cancers. RESULTS: We identified 64 point mutations in the 9 patients. Recurrent somatically acquired mutations were identified in SF3B1. Follow-up revealed SF3B1 mutations in 72 of 354 patients (20%) with myelodysplastic syndromes, with particularly high frequency among patients whose disease was characterized by ring sideroblasts (53 of 82 [65%]). The gene was also mutated in 1 to 5% of patients with a variety of other tumor types. The observed mutations were less deleterious than was expected on the basis of chance, suggesting that the mutated protein retains structural integrity with altered function. SF3B1 mutations were associated with down-regulation of key gene networks, including core mitochondrial pathways. Clinically, patients with SF3B1 mutations had fewer cytopenias and longer event-free survival than patients without SF3B1 mutations. CONCLUSIONS: Mutations in SF3B1 implicate abnormalities of messenger RNA splicing in the pathogenesis of myelodysplastic syndromes. (Funded by the Wellcome Trust and others.).
Asunto(s)
Síndromes Mielodisplásicos/genética , Fosfoproteínas/genética , Mutación Puntual , Ribonucleoproteína Nuclear Pequeña U2/genética , Eritrocitos/patología , Perfilación de la Expresión Génica , Secuenciación de Nucleótidos de Alto Rendimiento , Humanos , Fenotipo , Factores de Empalme de ARNRESUMEN
AIMS: A recent study that evaluated 22 methods for enumerating faecal indicator bacteria in sand recommended standardization to a preferred method, but all researchers involved in that study had extensive experience in processing sand samples. The purpose of this study was to evaluate how well the recommended method can be transferred to laboratories without such experience. METHODS AND RESULTS: Eight southern California laboratories that rarely measure bacteria in sand processed six sand and three water samples in replicates to assess repeatability. Among-laboratory variability was found to be less than within-laboratory variability, with no significant differences in results among any of the laboratories. Moreover, within-laboratory variability was comparable between the sand and water samples, indicating that the elution procedure added little additional method error even when performed by laboratories without prior experience. CONCLUSIONS: The simple extraction method for enumerating Enterococcus in beach sands was easily transferable to and repeatable among laboratories with little or no prior experience. SIGNIFICANCE AND IMPACT OF THE STUDY: The demonstrated success of technology transfer will further demonstrate the success of method standardization and adoption, aiding in understanding of how sands affect surface water quality.
Asunto(s)
Enterococcus/aislamiento & purificación , Monitoreo del Ambiente/métodos , California , Heces/microbiología , Humanos , Agua de Mar/microbiología , Dióxido de Silicio , Calidad del AguaRESUMEN
OBJECTIVE: To determine whether patients would have equivalent or improved outcomes when receiving non-surgical management versus surgical removal for vocal process granulomas. METHODS: A chart review was performed for 53 adults with vocal process granulomas. All patients received baseline anti-reflux treatment consisting of twice-daily proton pump inhibitors and vocal hygiene education. Further treatment approaches were divided into non-surgical (i.e. inhaled corticosteroids, voice therapy, botulinum toxin injections) and surgical groups. Subjective parameters (Voice Handicap Index 10 and Reflux Symptom Index) and outcomes were tabulated and statistically compared. Cause of granuloma was also analysed to determine if this influenced outcomes. RESULTS: Of 53 patients, 47 (89 per cent) experienced reduction in granuloma size, while 37 (70 per cent) experienced complete resolution. The rate of complete granuloma resolution after initial treatment strategy alone was significantly higher in non-surgical compared to surgical patients (67 and 30 per cent, respectively; p = 0.039). No difference in outcome was seen between iatrogenic and idiopathic granulomas. CONCLUSION: Non-surgical patients were more likely to experience initial treatment success than those who underwent surgical removal. Continued emphasis should be placed on conservative treatment options prior to surgery for patients with this condition.
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Granuloma/terapia , Laringitis/terapia , Inhibidores de la Bomba de Protones/uso terapéutico , Pliegues Vocales/fisiopatología , Adulto , Anciano , Terapia Combinada , Manejo de la Enfermedad , Femenino , Humanos , Masculino , Persona de Mediana Edad , Procedimientos Quirúrgicos Otorrinolaringológicos , Inhibidores de la Bomba de Protones/farmacología , Resultado del Tratamiento , Pliegues Vocales/efectos de los fármacos , Calidad de la Voz/efectos de los fármacos , Entrenamiento de la VozRESUMEN
AIMS: The absence of standardized methods for quantifying faecal indicator bacteria (FIB) in sand hinders comparison of results across studies. The purpose of the study was to compare methods for extraction of faecal bacteria from sands and recommend a standardized extraction technique. METHODS AND RESULTS: Twenty-two methods of extracting enterococci and Escherichia coli from sand were evaluated, including multiple permutations of hand shaking, mechanical shaking, blending, sonication, number of rinses, settling time, eluant-to-sand ratio, eluant composition, prefiltration and type of decantation. Tests were performed on sands from California, Florida and Lake Michigan. Most extraction parameters did not significantly affect bacterial enumeration. anova revealed significant effects of eluant composition and blending; with both sodium metaphosphate buffer and blending producing reduced counts. CONCLUSIONS: The simplest extraction method that produced the highest FIB recoveries consisted of 2 min of hand shaking in phosphate-buffered saline or deionized water, a 30-s settling time, one-rinse step and a 10 : 1 eluant volume to sand weight ratio. This result was consistent across the sand compositions tested in this study but could vary for other sand types. SIGNIFICANCE AND IMPACT OF THE STUDY: Method standardization will improve the understanding of how sands affect surface water quality.
Asunto(s)
Playas , Enterococcus/aislamiento & purificación , Escherichia coli/aislamiento & purificación , Sedimentos Geológicos/microbiología , Tamaño de la Partícula , Dióxido de SilicioRESUMEN
AIMS: The species identification and antimicrobial resistance profiles were determined for enterococci isolated from Southern California surface and ocean waters. METHODS AND RESULTS: Species identification was determined for 1413 presumptive Enterococcus isolates from urban runoff, bay, ocean and sewage water samples. The most frequently isolated species were Enterococcus faecalis, Enterococcus faecium, Enterococcus hirae, Enterococcus casseliflavus and Enterococcus mundtii. All five of these species were isolated from ocean and bay water with a frequency ranging from 7% to 36%. Enterococcus casseliflavus was the most frequently isolated species in urban runoff making up 36-65% of isolates while E. faecium was the most frequently isolated species in sewage making up 53-78% of isolates. The similar distribution of species in urban runoff and receiving water suggests that urban runoff may be the source of Enterococcus. No vancomycin or high level gentamycin resistance was detected in E. faecalis and E. faecium isolates. CONCLUSIONS: Enterococcus faecalis, E. faecium, E. casseliflavus and E. mundtii are the most commonly isolated Enterococcus species from urban runoff and receiving waters in Southern California. SIGNIFICANCE AND IMPACT OF THE STUDY: Determination of the Enterococcus species isolated from receiving waters and potential pollution sources may assist in determining the sources of pollution.
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Farmacorresistencia Bacteriana Múltiple , Enterococcus/aislamiento & purificación , Microbiología del Agua , Ciudades , Farmacorresistencia Microbiana , Enterococcus/fisiología , Enterococcus faecalis/aislamiento & purificación , Enterococcus faecalis/fisiología , Enterococcus faecium/aislamiento & purificación , Enterococcus faecium/fisiología , Monitoreo del Ambiente/métodos , Pruebas de Sensibilidad Microbiana , Lluvia , Aguas del Alcantarillado/microbiologíaRESUMEN
Gender affirmation surgeries in male-to-female patient transitioning include breast augmentation, genital construction, and facial feminization surgery (FFS). FFS improves mental health and quality of life in transgender patients. The nose and forehead are critical in facial attractiveness and gender identity; thus, frontal brow reduction and rhinoplasty are a mainstay of FFS. The open approach to reduction of the frontal brow is very successful in the feminization of the face; however, risks include alopecia and scarring. Endoscopic brow reduction, in properly selected patients, is minimally invasive with excellent outcomes avoiding these risks. Since both reduction rhinoplasty and frontal brow reduction are routinely performed in FFS, a combined approach provides superior control over the nasal radix and profile when performing surgery on the frontal bone region first followed by nose reduction. We present a case series of four transwomen undergoing frontal bone reduction in combination with a reduction rhinoplasty. All had excellent results with one DVT that resolved with treatment. Transgender patients frequently require multiple operations during their transition increasing their hospital stay and costs. This combined approach offers superior control over the nasofrontal angle and is not only safe but reduces hospitalizations and costs and is a novel indication to reduce gender dysphoria.
RESUMEN
Many teleosts including zebrafish, Danio rerio, actively regulate buoyancy with a gas-filled swimbladder, the volume of which is controlled by autonomic reflexes acting on vascular, muscular, and secretory effectors. In this study, we investigated the morphological development of the zebrafish swimbladder together with its effectors and innervation. The swimbladder first formed as a single chamber, which inflated at 1-3 days posthatching (dph), 3.5-4 mm body length. Lateral nerves were already present as demonstrated by the antibody zn-12, and blood vessels had formed in parallel on the cranial aspect to supply blood to anastomotic capillary loops as demonstrated by Tie-2 antibody staining. Neuropeptide Y-(NPY-) like immunoreactive (LIR) fibers appeared early in the single-chambered stage, and vasoactive intestinal polypeptide (VIP)-LIR fibers and cell bodies developed by 10 dph (5 mm). By 18 dph (6 mm), the anterior chamber formed by evagination from the cranial end of the original chamber; both chambers then enlarged with the ductus communicans forming a constriction between them. The parallel blood vessels developed into an arteriovenous rete on the cranial aspect of the posterior chamber and this region was innervated by zn-12-reactive fibers. Tyrosine hydroxylase- (TH-), NPY-, and VIP-LIR fibers also innervated this area and the lateral posterior chamber. Innervation of the early anterior chamber was also demonstrated by VIP-LIR fibers. By 25-30 dph (8-9 mm), a band of smooth muscle formed in the lateral wall of the posterior chamber. Although gas in the swimbladder increased buoyancy of young larvae just after first inflation, our results suggest that active control of the swimbladder may not occur until after the formation of the two chambers and subsequent development and maturation of vasculature, musculature and innervation of these structures at about 28-30 dph.
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Sacos Aéreos/crecimiento & desarrollo , Sacos Aéreos/inervación , Pez Cebra/crecimiento & desarrollo , Fibras Adrenérgicas/ultraestructura , Sacos Aéreos/irrigación sanguínea , Sacos Aéreos/ultraestructura , Animales , Vasos Sanguíneos/crecimiento & desarrollo , Fibras Colinérgicas/ultraestructura , Femenino , Estadios del Ciclo de Vida/fisiología , Masculino , Desarrollo de Músculos/fisiología , Músculos/inervación , Pez Cebra/fisiologíaRESUMEN
Fecal indicator bacteria concentrations measured in the surf zone off Huntington Beach, CA from July 1998-December 2001 were analyzed with respect to their spatial patterns along 23 km of beach, and temporal variability on time scales from hourly to fortnightly. The majority of samples had bacterial concentrations less than, or equal to, the minimum detection limit, but a small percentage exceeded the California recreational water standards. Areas where coliform bacteria exceeded standards were more prevalent north of the Santa Ana River, whereas enterococci exceedances covered a broad area both north and south of the river. Higher concentrations of bacteria were associated with spring tides. No temporal correspondence was found between these bacterial events and either the timing of cold water pulses near shore due to internal tides, or the presence of southerly swell in the surface wave field. All three fecal indicator bacteria exhibited a diel cycle, but enterococci rebounded to high nighttime values almost as soon as the sun went down, whereas coliform levels were highest near the nighttime low tide, which was also the lower low tide.
Asunto(s)
Enterobacteriaceae/aislamiento & purificación , Heces/microbiología , Agua de Mar/microbiología , Microbiología del Agua , Contaminantes del Agua/análisis , Fenómenos Fisiológicos Bacterianos , Playas/normas , California , Recuento de Colonia Microbiana/métodos , Demografía , Enterobacteriaceae/crecimiento & desarrollo , Enterobacteriaceae/fisiología , Geografía , Humanos , Salud Pública , Recreación , Factores de Tiempo , Movimientos del AguaRESUMEN
OBJECTIVES: People with Down syndrome (DS) are at high risk for developing dementia and early diagnosis is vital in enhancing quality of life. Our aim was to compare our practice to consensus recommendations on evaluation, diagnosis and pharmacological treatment of individuals with DS who develop dementia. We also aimed to establish the average time taken to make a diagnosis of dementia and to commence pharmacotherapy, and to assess tolerability to acetylcholinesterase inhibitors. METHODS: Retrospective chart review in an exhaustive sample containing all current service users attending our service with DS and a diagnosis of dementia (n=20). RESULTS: The sample was 75% female and 70% had a moderate intellectual disability. The average age at diagnosis of dementia was 52.42 years old. The average time to diagnosis from first symptom was 1.13 years and the average time to commence pharmacotherapy was 0.23 years. A total of 17 patients commenced on acetylcholinesterase inhibitors, and of these seven discontinued medication due to side-effects or lack of efficacy. CONCLUSIONS: The results on anticholinesterases add to the limited pool of data on treatment of dementia in DS. There was an identified need to improve the rates of medical, vision and hearing assessments, and prospective screening. Deficiencies in screening and diagnosis may be addressed by implementing a standardised dementia assessment pathway to include prospective screening and longitudinal assessment using easily administered scales. We highlight the importance of improving the diagnostic process, as a vital window of opportunity to commence a comprehensive care plan may be lost.
RESUMEN
In a prospective protocol, plasma tocopherols, selenium (Se), Se-dependent glutathione peroxidase, platelet aggregation and erythrocyte hemolysis were measured in 23 control subjects, and 15 patients receiving total parenteral nutrition (TPN), before and after 2 wk of TPN unsupplemented with vitamin E and Se. The results indicate that short-term TPN did not alter status of these nutrients. However, TPN patients had significantly lower plasma levels of Se (p less than 0.01) and alpha-tocopherol (p less than 0.01) relative to control subjects. Low plasma levels, with no attendant decrease in function, suggest a marginal depletion. In view of this, and considering the low amount of vitamin E and Se supplied by the TPN solutions, supplementation with these nutrients is recommended.
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Nutrición Parenteral Total , Nutrición Parenteral , Selenio/sangre , Vitamina E/sangre , Adolescente , Adulto , Anciano , Femenino , Glutatión Peroxidasa/metabolismo , Hemólisis , Humanos , Masculino , Persona de Mediana Edad , Agregación PlaquetariaRESUMEN
The conclusion to be drawn from our modeling is that the combined stretch and tendon reflexes alone can endow artificial muscle with a springlike feel as well as give it a baseline tone. In response to questions that motor physiologists often ask as to what variables the system controls, the answer here is clear: the stretch and tendon reflexes act together to maintain both a tension set-point and a length set-point, but in so doing they also give the system a springlike feel because of the existence of a servo error. The main goal of our studies is to understand the integration of reflexes, and thus far we have only begun to explore the two lowest-level spinal reflexes. We are in the process of expanding this work by developing a much more refined arm explicitly modeled after the human arm. This new arm is to be activated by a minimum of 10 muscles, each of which is reflexively driven, and it will allow us to explore the integration of higher-level reflex action such as automatic inhibition of antagonists and facilitation of synergists.
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Músculos/fisiología , Reflejo/fisiología , Tendones/fisiología , Humanos , Modelos EstructuralesRESUMEN
This study was designed to investigate the effects of aging and caloric restriction on collagen deposition in a model of wound healing. Polyvinyl alcohol sponges were implanted in Fischer 344 rats aged 6, 10, or 24 months. Sponges were removed after 7, 10, or 14 days and analyzed for hydroxyproline content and for enzymatic crosslinks. Aging was associated with a decrease in collagen accumulation as well as a delay in reaching peak rates of collagen accumulation. Levels of enzymatic crosslinks were increased in granulation tissue from old animals relative to young animals. Caloric restriction (60% of ad libitum intake) maintained only during the 2-week experimental period did not affect collagen accumulation, but did result in decreased levels of the difunctional crosslink dihydroxylysinonor-leucine (DHLNL) in sponges implanted for 10 days, but not 14 days. Caloric restriction initiated 4 months before sponges were implanted resulted in decreased collagen accumulation and decreases in DHLNL at all implantation times. These studies suggest that: (1) aging affects total collagen production as well as rate of collagen production in response to injury; (2) aging is not associated with impaired crosslinking in granulation tissue; (3) chronic caloric restriction is associated with decreased collagen production and decreased levels of DHLNL; (4) the adverse effects of chronic caloric restriction on wound healing may have a greater impact on wound healing in old animals.
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Envejecimiento/metabolismo , Colágeno/biosíntesis , Ingestión de Energía , Cicatrización de Heridas/fisiología , Animales , Arginina/análogos & derivados , Arginina/metabolismo , Reactivos de Enlaces Cruzados/metabolismo , Dipéptidos/metabolismo , Tejido de Granulación/metabolismo , Lisina/análogos & derivados , Lisina/metabolismo , Masculino , Ratas , Ratas Endogámicas F344 , Factores de TiempoRESUMEN
The effects of catecholamines on the regulation of lipoprotein metabolism have not been defined. We examined the effects of subcutaneously administered slow-release preparations of norepinephrine (2 mg/kg) and isoproterenol (0.2 mg/kg) on the serum lipoproteins of New Zealand White rabbits. Drugs or control suspension were administered daily to three groups of normally fed and three groups of cholesterol-fed rabbits, and lipoprotein analysis was performed at intervals over a 60-hour period. In the normally fed animals, norepinephrine increased the serum levels of triglyceride and phospholipid by factors of 2.4 (P less than .01) and 1.35 (P less than .05), respectively, compared with control animals at 60 hours, but had no effect on serum cholesterol. All components of serum very low density lipoproteins (VLDL: triglyceride, cholesterol, phospholipid, and protein) were significantly (P less than .01) elevated by norepinephrine in the normally fed animals. In the cholesterol-fed animals, norepinephrine at 60 hours significantly increased total serum cholesterol, triglyceride, and phospholipid concentrations by factors of 1.7 (P less than .05), 5.0 (P less than .01), and 1.6 (P less than .05), respectively, compared with controls. The norepinephrine effects in these animals was due to significant elevation of total VLDL and low density lipoproteins (LDL) and all their elemental components. Isoproterenol produced no significant effect on serum lipoprotein levels in the normally fed rabbit, but in cholesterol-fed animals it produced a rise in total serum VLDL and LDL triglyceride concentrations compared with controls at 60 hours. These data demonstrate that catecholamines are involved in the regulation of lipoprotein metabolism.
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Catecolaminas/farmacología , Colesterol en la Dieta/farmacología , Lipoproteínas/sangre , Animales , HDL-Colesterol/sangre , Isoproterenol/farmacología , Lipoproteínas HDL/sangre , Lipoproteínas LDL/sangre , Lipoproteínas VLDL/sangre , Masculino , Norepinefrina/farmacología , Fosfolípidos/sangre , Conejos , Triglicéridos/sangreRESUMEN
We previously reported differences in protein and carbohydrate selection patterns in post-weanling rats fed beef tallow or soybean oil-based diets. Two experiments were designed to determine the characteristic of the dietary fat which mediates the selection behavior. For each experiment, dietary fat was 20% (w/w) of diets and fatty acid profiles were obtained by blending fat sources. Rats were randomly assigned to diets (24% protein, 40% carbohydrate) which varied only in fatty acid composition. After 2 weeks, rats selected from 2 diets with the fat composition previously fed, but varying in their protein and carbohydrate composition (55% protein, 4% carbohydrate and 5% protein, 61% carbohydrate). Experiment 1 was designed to test the effect of relative (omega 6: omega 3 ratios of 1 and 20) and absolute (15% or 4% omega 6, 0.7% or 0.2% omega 3) differences in essential fatty acids on macronutrient selection patterns. Differences in dietary essential fatty acids had no effect on energy intake or the proportion of energy consumed as protein and carbohydrate. Experiment 2 examined the effect of differences in the level of saturated fat (3-10% diet (w/w] on protein and carbohydrate selection. Animals selecting from diets with higher levels of saturated fat consumed more energy as protein and less as carbohydrate than rats selecting from diets with lower levels of saturated fat (p less than 0.0001). Regression analysis was used to examine the relationship between percent protein or carbohydrate energy and classes of dietary fat. The strongest relationship existed between percent dietary saturated fat and percent protein or carbohydrate energy (p less than 0.0001). Polyunsaturated:saturated fat ratio was also weakly associated with percent protein and carbohydrate energy (p less than 0.05). Polyunsaturated, monounsaturated, omega 6 and omega 3 fatty acids were not significantly related to percent protein or carbohydrate energy. These results indicated that protein and carbohydrate selection patterns are altered in response to qualitatively different dietary fatty acids, and that the amount of saturated fat in the diet is the important characteristic of dietary fat mediating the behavioral alteration.
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Carbohidratos de la Dieta/fisiología , Grasas de la Dieta/fisiología , Proteínas en la Dieta/fisiología , Ácidos Grasos Esenciales/fisiología , Ácidos Grasos/fisiología , Preferencias Alimentarias/fisiología , Análisis de Varianza , Animales , Método Doble Ciego , Ingestión de Energía , Masculino , Distribución Aleatoria , Ratas , Ratas Endogámicas , Análisis de RegresiónRESUMEN
We previously showed changes in protein and carbohydrate selection in response to qualitative differences in dietary fat. Alterations in macronutrient selection were specifically related to changes in dietary saturated fat, but not to relative or absolute differences in dietary essential fatty acids. Three experiments were conducted to determine if changes in specific fatty acids in bulk phase neural membranes were associated with differences in macronutrient selection. For each experiment, specific fatty acid profiles were achieved by blending dietary fat sources. Rats consumed 20% (w/w) fat diets varying only in their fatty acid composition. After 2 weeks, rats were challenged with a selection paradigm. Each experiment showed a significant effect of dietary fat on neural membrane fatty acid composition (p less than 0.05) and alterations in individual fatty acids were correlated with changes in dietary fatty acids (p less than 0.05). However, dietary fat had no consistent effect with respect to which particular neural membrane fatty acids were modified, and there was no correlation between changes in specific membrane fatty acids and macronutrient selection. These findings suggest that alteration of specific fatty acids in bulk phase neural membranes do not mediate macronutrient selection behavior.
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Química Encefálica/efectos de los fármacos , Grasas de la Dieta/farmacología , Ácidos Grasos/análisis , Neuronas/química , Sinaptosomas/química , Animales , Membrana Celular/química , Grasas de la Dieta/administración & dosificación , Conducta Alimentaria/efectos de los fármacos , Masculino , Ratas , Ratas Endogámicas , Sinaptosomas/efectos de los fármacosRESUMEN
The correction or maintenance of blood and tissue alpha-tocopherol (alpha-Toc) levels by intraperitoneally administered all-rac-alpha-tocopheryl acetate (alpha-Tac) was compared with RRR- alpha-tocopherol (alpha-Toc) in vitamin E-depleted and control rats. Rats received 1.3 TE vitamin E daily for 7 days. alpha-Tac was detected in plasma of one-third of alpha-Tac-treated rats 24 hr after the first treatment, although not in subsequent samplings. Both alpha-Tac and alpha-Toc increased tocopherol levels in plasma and liver of E-deprived rats, while little or no change was observed in adipose tissue and brain. Similarly, control rats treated with alpha-Tac or alpha-Toc had significantly greater (p less than 0.05) plasma and liver alpha-Toc levels at day 3 and day 7 than did saline-treated rats. There was no significant difference in adipose alpha-Toc levels among treatment groups of control rats. The results of this study suggest that alpha-Tac is rapidly hydrolyzed to its biologically active alcohol form and results in similar effects to that of intraperitoneally administered alpha-Toc.
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Vitamina E/análogos & derivados , Vitamina E/metabolismo , alfa-Tocoferol/análogos & derivados , Animales , Peso Corporal , Relación Dosis-Respuesta a Droga , Inyecciones Intraperitoneales , Masculino , Ratas , Ratas Endogámicas , Factores de Tiempo , Distribución Tisular/efectos de los fármacos , Tocoferoles , Vitamina E/administración & dosificación , Vitamina E/farmacología , Deficiencia de Vitamina E/metabolismoRESUMEN
Stability of alpha-tocopherol acetate and selenium in amino acid/dextrose solutions with SoluZyme or MVI-1000 vitamin injections was evaluated following exposure to fluorescent lighting and room temperature, and after flowing through an infusion apparatus. The stability of selenium in parenteral solutions for a 10-wk period was also determined. In each condition no significant loss of alpha-tocopherol acetate or selenium was observed. It was concluded that alpha-tocopherol acetate and selenium as selenious acid are stable in parenteral solutions and no significant loss occurs during delivery to patients.
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Infusiones Parenterales , Selenio , Vitamina E , Estabilidad de Medicamentos , Almacenaje de Medicamentos , Iluminación , Nutrición Parenteral Total , TemperaturaRESUMEN
The results of a survey on the status of pharmacy-based investigational drug services and ways in which some institutions have adapted to recent changes that may affect research are presented. A 99-item survey on investigational drug services was sent in February 1997 to pharmacy directors at 1495 hospitals affiliated with teaching institutions throughout the United States. The survey covered workload, inpatient and outpatient pharmaceutical services, marketing of services, quality assurance, committee involvement, funding sources, computerization, and educational activities. The response rate was 21%; 68% of the respondents were from sites involved in dispensing drugs used for clinical research, with pharmacies at larger hospitals being more likely to dispense investigational drugs than pharmacies at smaller hospitals. The pharmacies participated in a mean 51 active protocols for every full-time-equivalent employee budgeted to research protocols. The correlation between staffing level and number of protocols was high. The service provided most often was the maintenance of drug accountability records for study drugs dispensed to inpatients and outpatients. There was wide variation in the types of services provided to researchers by the pharmacies. Basic services, such as dispensing and inventory control, were provided by nearly all the pharmacies, whereas more-specialized services tended to be provided more often at institutions more heavily committed to research. Pharmacy-based investigational drug services at hospitals affiliated with teaching institutions offered basic services, such as dispensing and inventory control, almost universally and offered specialized services to varying degrees.