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BACKGROUND: Community paramedicine programs (i.e., physician-directed preventive care by emergency medical services personnel embedded in communities) offer a novel approach to community-based health care. Project Swaddle, a community paramedicine program for mothers and their infants, seeks to address (directly or through referrals) the physical, mental, social, and economic needs of its participants. The objective of this process evaluation was to describe women's experiences in Project Swaddle. By understanding their experiences, our work begins to build the foundation for similar programs and future examinations of the efficacy and effectiveness of these approaches. METHODS: We completed 21 interviews with women living in Indiana (July 2019-February 2020) who were currently participating in or had graduated from Project Swaddle. Interviews were audio-recorded, transcribed, and analyzed using a six-phase approach to thematic analysis. RESULTS: Program enrollment was influenced by the community paramedics' experience and connections, as well as information received in the community from related clinics or organizations. Participants viewed the community paramedic as a trusted provider who supplied necessary health information and support and served as their advocate. In their role as physician extenders, the community paramedics enhanced patient care through monitoring critical situations, facilitating communication with other providers, and supporting routine healthcare. Women noted how community paramedics connected them to outside resources (i.e., other experts, tangible goods), which aimed to support their holistic health and wellbeing. CONCLUSIONS: Results demonstrate Project Swaddle helped women connect with other healthcare providers, including increased access to mental health services. The community paramedics were able to help women establish care with primary care providers and pediatricians, then facilitate communication with these providers. Women were supported through their early motherhood experience, received education on parenting and taking control of their health, and gained access to resources that met their diverse needs.
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Servicios Médicos de Urgencia , Auxiliares de Urgencia , Técnicos Medios en Salud , Servicios de Salud Comunitaria , Femenino , Humanos , Lactante , Investigación CualitativaRESUMEN
Safety monitoring and successful blinding are important features of randomized, blinded clinical trials. We report chamber- and protocol-related adverse events (AEs) for participants enrolled in two randomized, double-blind clinical trials of hyperbaric oxygen (HBO2) for persistent post-concussive symptoms clinicaltrials.gov identifiers NCT01306968, HOPPS, and NCT01611194, BIMA), as well as the success of maintaining the blind with a low-pressure sham control arm. In both studies, participants were randomized to receive HBO2 (1.5 atmospheres absolute, >99% oxygen) or sham chamber sessions (1.2 atmospheres absolute, room air). In 143 participants undergoing 4,245 chamber sessions, chamber-related adverse events were rare (1.1% in the HOPPS study, 2.2% in the BIMA study). Minor, non-limiting barotrauma was the most frequently reported. Rarely, some participants experienced headache with chamber sessions. No serious adverse events were associated with chamber sessions. An allocation questionnaire completed after intervention revealed that the sham control arm adequately protected the blind in both trials. Participants based allocation assumptions on symptom improvement or lack of symptom improvement and could not discern intervention arm by pressure, smell, taste, or gas flow.
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Oxigenoterapia Hiperbárica/efectos adversos , Síndrome Posconmocional/terapia , Adulto , Barotrauma/etiología , Conmoción Encefálica/complicaciones , Método Doble Ciego , Dolor de Oído/etiología , Femenino , Cefalea/etiología , Humanos , Oxigenoterapia Hiperbárica/métodos , Masculino , Personal Militar , Proyectos Piloto , Distribución Aleatoria , SeguridadRESUMEN
Biologic therapies are injectable immunomodulatory agents directed against specific immune cell or chemical targets. They have transformed the lives of HIV-uninfected individuals with severe inflammatory conditions including psoriasis, rheumatoid arthritis, and ulcerative colitis. The perceived increased infection risk associated with these agents means that HIV-infected individuals have not been included in randomised control trials of these drugs. The literature for use of biologic therapies in HIV-infected populations is limited to case reports and case series. There are additional data on use of rituximab, a monoclonal antibody against B lymphocytes, in the setting of HIV-associated haematological malignancy. We performed a systematic review of efficacy and safety of biologic therapy for inflammatory conditions in HIV-infected individuals. Our systematic review identified 37 treatment episodes with six different biologic agents encompassing 10 different inflammatory conditions. Broadly, efficacy of the agents studied was comparable to reports from HIV-uninfected patients. Both infectious and non-infectious sequelae were also comparable with trial data from HIV-uninfected patients. HIV control, even for the minority of individuals not receiving anti-retroviral therapy (ART) at the time of biologic therapy, was not adversely affected. However, detail was limited concerning ART regimens and both immunological and virological parameters of follow-up. Overall available literature is of very low quality and likely subject to publication bias of successful cases. Firm conclusions are not possible regarding the efficacy and safety of biologic agents in HIV-infected individuals; however, there appear to be sufficient data to warrant inclusion of individuals with well-controlled HIV in future trial studies.
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Productos Biológicos/uso terapéutico , Terapia Biológica , Infecciones por VIH/complicaciones , Inflamación/terapia , Productos Biológicos/administración & dosificación , Humanos , Resultado del TratamientoRESUMEN
Simple reaction time (SRT) and procedural reaction time (PRT) are speed-of-processing tasks in the Automated Neuropsychological Assessment Metrics (ANAM) that may be sensitive to mild traumatic brain injury (mTBI). The investigators measured SRT and PRT throughput (correct responses per minute) at baseline, 6 weeks, and 13 weeks in military personnel with mTBI randomized to local care or 40 chamber sessions (sham-1.2 atmospheres absolute [ATA] air, hyperbaric oxygen-1.5 ATA O2). Scores were assessed at baseline using univariate analysis of variance and across time with repeated measures methods. Data reported as throughput standard scores (mean = 100, SD = 15). Seventy-two participants with ongoing symptoms after mTBI enrolled in the study (three female, median age 31 years, mean three lifetime concussion events, most recent mTBI 23 months prior). Sixty-four had Automated Neuropsychological Assessment Metrics data at 13 weeks. SRT and PRT throughput standard scores were comparable across groups at baseline. Over time, SRT scores did not change in the hyperbaric oxygen or sham groups and decreased in the local care group. PRT throughput standard scores increased from baseline to mid-intervention and decreased from mid-intervention to postintervention in all groups. Repeated measures change over time in SRT (p = 0.23), and PRT (p = 0.17) scores were not different among groups. This study may be underpowered to detect statistically significant change.
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Conmoción Encefálica/terapia , Oxigenoterapia Hiperbárica/métodos , Personal Militar/psicología , Tiempo de Reacción , Adulto , Conmoción Encefálica/clasificación , Conmoción Encefálica/complicaciones , Lesiones Encefálicas/psicología , Lesiones Encefálicas/terapia , Disfunción Cognitiva , Femenino , Humanos , Masculino , Persona de Mediana Edad , Pruebas Neuropsicológicas , Oxígeno/uso terapéuticoAsunto(s)
Oxigenoterapia Hiperbárica , Personal Militar , Síndrome Posconmocional/terapia , Calidad de Vida , Femenino , Humanos , MasculinoRESUMEN
IMPORTANCE: Improvement has been anecdotally observed in patients with persistent postconcussion symptoms (PCS) after mild traumatic brain injury following treatment with hyperbaric oxygen (HBO). The effectiveness of HBO as an adjunctive treatment for PCS is unknown to date. OBJECTIVES: To compare the safety of and to estimate the efficacy for symptomatic outcomes from standard PCS care alone, care supplemented with HBO, or a sham procedure. DESIGN, SETTING, AND PARTICIPANTS: Multicenter, double-blind, sham-controlled clinical trial of 72 military service members with ongoing symptoms at least 4 months after mild traumatic brain injury enrolled at military hospitals in Colorado, North Carolina, California, and Georgia between April 26, 2011, and August 24, 2012. Assessments occurred before randomization, at the midpoint, and within 1 month after completing the interventions. INTERVENTIONS: Routine PCS care was provided in specialized clinics. In addition, participants were randomized 1:1:1 to 40 HBO sessions administered at 1.5 atmospheres absolute (ATA), 40 sham sessions consisting of room air at 1.2 ATA, or no supplemental chamber procedures. MAIN OUTCOMES AND MEASURES: The Rivermead Post-Concussion Symptoms Questionnaire (RPQ) served as the primary outcome measure. A change score of at least 2 points on the RPQ-3 subscale (range, 0-12) was defined as clinically significant. Change scores from baseline were calculated for the RPQ-3 and for the total RPQ. Secondary measures included additional patient-reported outcomes and automated neuropsychometric testing. RESULTS: On average, participants had sustained 3 lifetime mild traumatic brain injuries; the most recent occurred 23 months before enrollment. No differences were observed between groups for improvement of at least 2 points on the RPQ-3 subscale (25% in the no intervention group, 52% in the HBO group, and 33% in the sham group; P = .24). Compared with the no intervention group (mean change score, 0.5; 95% CI, -4.8 to 5.8; P = .91), both groups undergoing supplemental chamber procedures showed improvement in symptoms on the RPQ (mean change score, 5.4; 95% CI, -0.5 to 11.3; P = .008 in the HBO group and 7.0; 95% CI, 1.0-12.9; P = .02 in the sham group). No difference between the HBO group and the sham group was observed (P = .70). Chamber sessions were well tolerated. CONCLUSIONS AND RELEVANCE: Among service members with persistent PCS, HBO showed no benefits over sham compressions. Both intervention groups demonstrated improved outcomes compared with PCS care alone. This finding suggests that the observed improvements were not oxygen mediated but may reflect nonspecific improvements related to placebo effects. TRIAL REGISTRATION: clinicaltrials.gov Identifier: NCT01306968.
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Oxigenoterapia Hiperbárica , Personal Militar , Síndrome Posconmocional/terapia , Calidad de Vida , Adulto , Método Doble Ciego , Femenino , Humanos , Masculino , Resultado del Tratamiento , Estados Unidos , Adulto JovenRESUMEN
Mycorrhizal phenotypes arise from interactions among plant and fungal genotypes and the environment. Differences in the stoichiometry and uptake capacity of fungi and plants make arbuscular mycorrhizal (AM) fungi inherently more nitrogen (N) limited and less phosphorus (P) limited than their host plants. Mutualistic phenotypes are most likely in P-limited systems and commensal or parasitic phenotypes in N-limited systems. Carbon (C) limitation is expected to cause phenotypes to shift from mutualism to commensalism and even parasitism. Two experiments compared the influence of fertilizer and shade on mycorrhizas in Andropogon gerardii across three naturally N-limited or P-limited grasslands. A third experiment examined the interactive effects of N and P enrichment and shade on A. gerardii mycorrhizas. Our experiments generated the full spectrum of mycorrhizal phenotypes. These findings support the hypothesis that mutualism is likely in P-limited systems and commensalism or parasitism is likely in N-limited systems. Furthermore, shade decreased C-assimilation and generated less mutualistic mycorrhizal phenotypes with reduced plant and fungal biomass. Soil fertility is a key controller of mycorrhizal costs and benefits and the Law of the Minimum is a useful predictor of mycorrhizal phenotype. In our experimental grasslands arbuscular mycorrhizas can ameliorate P-limitation but not N-limitation.
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Modelos Biológicos , Micorrizas/fisiología , Análisis de Varianza , Andropogon/metabolismo , Andropogon/microbiología , Andropogon/efectos de la radiación , Carbono/metabolismo , Fertilizantes , Luz , Micorrizas/crecimiento & desarrollo , Nitrógeno/metabolismo , Fenotipo , Fósforo/metabolismo , Suelo/químicaAsunto(s)
Cámaras de Exposición Atmosférica , Lesiones Encefálicas/terapia , Aprobación de Recursos/legislación & jurisprudencia , Oxigenoterapia Hiperbárica , Cámaras de Exposición Atmosférica/normas , Aprobación de Recursos/normas , Humanos , Oxigenoterapia Hiperbárica/instrumentación , Oxigenoterapia Hiperbárica/métodos , Oxigenoterapia Hiperbárica/normas , Apoyo a la Investigación como Asunto , Estados Unidos , United States Food and Drug AdministrationAsunto(s)
Oxigenoterapia Hiperbárica , Síndrome Posconmocional/terapia , Animales , Lesiones Encefálicas/complicaciones , Lesiones Encefálicas/metabolismo , Ensayos Clínicos como Asunto , Humanos , Oxigenoterapia Hiperbárica/efectos adversos , Oxigenoterapia Hiperbárica/métodos , Registros Médicos , Consumo de Oxígeno/fisiología , Síndrome Posconmocional/metabolismo , RiesgoRESUMEN
Plantar dislocation of the 1st metatarsophalangeal joint is an extremely rare injury. To the best of our knowledge, there are no previous reports in the literature of an isolated dislocation of this type requiring open reduction and surgical repair. In this case report, we describe the clinical and operative findings and discuss in detail our surgical technique for the successful management of this unusual injury.
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Luxaciones Articulares/terapia , Articulación Metatarsofalángica/lesiones , Adulto , Humanos , Luxaciones Articulares/diagnóstico , Inestabilidad de la Articulación/etiología , Inestabilidad de la Articulación/terapia , Ligamentos Laterales del Tobillo/lesiones , Ligamentos Laterales del Tobillo/cirugía , Masculino , Manipulación Ortopédica , Artes Marciales/lesiones , Anclas para Sutura , Tendones/cirugíaRESUMEN
The hydrolysis of free fatty acids from lipids is a prerequisite for biohydrogenation, a process that effectively saturates free fatty acids. Anaerovibrio lipolyticus 5s and Butyrivibrio fibrisolvens have long been thought to be the major contributors to ruminal lipolysis; however, Propionibacterium avidum and acnes recently have been identified as contributing lipase activity in the rumen. In order to further characterize the lipase activity of these bacterial populations, each was grown with three different lipid substrates, olive oil, corn oil, and flaxseed oil (3 %). Because different finishing rations contain varying levels of glycogen (a source of free glucose) this study also documented the effects of glucose on lipolysis. P. avidum and A. lipolyticus 5s demonstrated the most rapid rates (P < 0.05) of lipolysis for cultures grown with olive oil and flaxseed oil, respectively. A. lipolyticus, B. fibrisolvens, and P. avidum more effectively hydrolyzed flaxseed oil than olive oil or corn oil, especially in the presence of 0.02 % glucose. Conversely, P. acnes hydrolyzed corn oil more readily than olive oil or flaxseed oil and glucose had no effect on lipolytic rate. Thus, these bacterial species demonstrated different specificities for oil substrates and different sensitivities to glucose.
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Butyrivibrio/enzimología , Glucosa/metabolismo , Lipasa/metabolismo , Aceites de Plantas/metabolismo , Propionibacterium/enzimología , Rumen/microbiología , Veillonellaceae/enzimología , Animales , Butyrivibrio/efectos de los fármacos , Butyrivibrio/crecimiento & desarrollo , Bovinos , Aceite de Maíz/metabolismo , Medios de Cultivo , Glucosa/farmacología , Aceite de Linaza/metabolismo , Lipólisis/efectos de los fármacos , Aceite de Oliva , Propionibacterium/efectos de los fármacos , Propionibacterium/crecimiento & desarrollo , Rumen/efectos de los fármacos , Especificidad por Sustrato , Veillonellaceae/efectos de los fármacos , Veillonellaceae/crecimiento & desarrolloRESUMEN
We demonstrate the generation of 22.6 µJ of combined energy at 3 µm for sub-300fs pulses at a repetition rate of 1 kHz using a LGSe optical parametric amplifier (OPA). The LGSe OPA is pumped by the 140-fs 1.6 µm pulses from a 300-mW KTA optical parametric chirped pulse amplifier (OPCPA) based on an all-optical synchronization scheme. By using a highly-nonlinear fiber, the output of an erbium-doped fiber laser operating at 1560 nm is shifted to 1050 nm in order to coherently seed a Nd:YLF regenerative amplifier. The LGSe OPA is seeded using the MIR coming from the amplification of the 1.6 µm in the OPCPA.
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Amplificadores Electrónicos , Rayos Infrarrojos , Láseres de Estado Sólido , Óptica y Fotónica/instrumentación , Óptica y Fotónica/métodos , Diseño de Equipo , Erbio/química , Galio/química , Litio/química , Dinámicas no Lineales , Selenio/químicaAsunto(s)
Androstadienos , Antirretrovirales , Prestación Integrada de Atención de Salud/organización & administración , Infecciones por VIH/tratamiento farmacológico , Hipolipemiantes , Comunicación Interdisciplinaria , Adulto , Androstadienos/administración & dosificación , Androstadienos/farmacocinética , Antiinflamatorios/administración & dosificación , Antiinflamatorios/farmacocinética , Antirretrovirales/administración & dosificación , Antirretrovirales/efectos adversos , Antirretrovirales/farmacocinética , Manejo de la Enfermedad , Interacciones Farmacológicas , Fluticasona , Humanos , Hiperlipidemias/inducido químicamente , Hiperlipidemias/tratamiento farmacológico , Hipolipemiantes/administración & dosificación , Hipolipemiantes/farmacocinética , MasculinoRESUMEN
The complementary drop and bubble profile analysis and maximum bubble pressure tensiometry are used to measure the dynamic surface tension of aqueous SDS solutions in the presence of hardness salts (CaCl(2) and MgCl(2) in the ratio of 2:1 at concentrations of 6 and 40FH). The presence of hardness salts results in an essential increase of the SDS adsorption activity, which indicates the formation of Ca(DS)(2) and Mg(DS)(2) in the SDS solutions. The surface tension isotherms of SDS in presence of Ca(DS)(2) and Mg(DS)(2) are described using the generalised Frumkin model. The presence of hardness salts accelerates the ageing of SDS solutions as compared with the addition of 0.01 M NaCl due to a faster hydrolysis and hence formation of dodecanol. These results are used to estimate the possible concentration of dodecanol in the studied SDS solutions. The buoyant bubble profile method with harmonic surface oscillations is used to measure the dilational rheology of SDS solutions in presence of hardness salts in the frequency range between 0.005 Hz and 0.2 Hz. The visco-elasticity modulus in the presence of hardness salts is higher as compared with its values in the presence of 0.01 M NaCl additions. The ageing of SDS solutions leads to an essential increase of the visco-elastic modulus.
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Cloruro de Calcio/química , Cloruro de Magnesio/química , Dodecil Sulfato de Sodio/química , Sustancias Viscoelásticas/química , Agua/química , Soluciones , Tensión SuperficialRESUMEN
Lipid oxidation is known to occur rather rapidly in cooked chicken meat containing relatively high amounts of polyunsaturated fatty acids. To assess the lipid oxidation stability of sous vide chicken meat enriched with n-3 and conjugated linoleic acid (CLA) fatty acids, 624 Cobb × Ross broilers were raised during a 6-wk feeding period. The birds were fed diets containing CLA (50% cis-9, trans-11 and 50% trans-10, cis-12 isomers), flaxseed oil (FSO), or menhaden fish oil (MFO), each supplemented with 42 or 200 mg/kg of vitamin E (dl-α-tocopheryl acetate). Breast or thigh meat was vacuum-packed, cooked (74°C), cooled in ice water, and stored at 4.4°C for 0, 5, 10, 15, and 30 d. The lipid oxidation development of the meat was estimated by quantification of malonaldehyde (MDA) values, using the 2-thiobarbituric acid reactive substances analysis. Fatty acid, nonheme iron, moisture, and fat analyses were performed as well. Results showed that dietary CLA induced deposition of cis-9, trans-11 and trans-10, cis-12 CLA isomers, increased the proportion of saturated fatty acids, and decreased the proportions of monounsaturated and polyunsaturated fatty acids. Flaxseed oil induced higher deposition of C18:1, C18:2, C18:3, and C20:4 fatty acids, whereas MFO induced higher deposition of n-3 fatty acids, eicosapentaenoic acid (C20:5), and docosahexaenoic acid (C22:6; P < 0.05). Meat lipid oxidation stability was affected by the interaction of either dietary oil or vitamin E with storage day. Lower (P < 0.05) MDA values were found in the CLA treatment than in the MFO and FSO treatments. Lower (P < 0.05) MDA values were detected in meat samples from the 200 mg/kg of vitamin E than in meat samples from the 42 mg/kg of vitamin E. Nonheme iron values did not affect (P > 0.05) lipid oxidation development. In conclusion, dietary CLA, FSO, and MFO influenced the fatty acid composition of chicken muscle and the lipid oxidation stability of meat over the storage time. Supranutritional supplementation of vitamin E enhanced the lipid oxidation stability of sous vide chicken meat.
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Ácidos Grasos Omega-3/química , Ácidos Linoleicos Conjugados/química , Peroxidación de Lípido , Carne/análisis , Alimentación Animal/análisis , Animales , Pollos , Culinaria , Dieta/veterinaria , Suplementos Dietéticos , Ácidos Grasos Omega-3/metabolismo , Aceites de Pescado/química , Ácidos Linoleicos Conjugados/metabolismo , Aceite de Linaza/química , Carne/normasRESUMEN
The fatty acid composition of chicken muscle may affect the lipid oxidation stability of the meat, particularly when subjecting the meat to thermal processing and storage. The objective of this study was to evaluate the diet effect on lipid oxidation stability of fresh and cooked chicken meat. Six hundred broilers were raised for a 6-wk feeding period and were assigned to 8 treatments with 3 repetitions. Broilers were fed a basal corn-soybean meal diet, including 5% of either animal-vegetable, lard, palm kernel, or soybean (SB) oil, each supplemented with a low (33 mg/kg) or high (200 to 400 mg/kg) level of vitamin E. Fresh breast and thigh meat and skin were packaged and refrigerated (4°C) for 15 d. Breast and thigh meat were frozen (-20°C) and stored for ~6 mo and then thawed, deboned, ground, and formed into patties of 150 g each. Patties were cooked (74°C), cooled, packaged, and stored in refrigeration for 6 d. The lipid oxidation development of the products was determined using the TBA reactive substances analysis. The results showed that the lipid oxidation development, in both fresh chicken parts and cooked meat patties, was influenced by the interaction of either dietary lipid source or vitamin E level with storage time. Fresh breast meat showed no susceptibility to lipid oxidation, but thigh meat and skin presented higher (P < 0.05) malonaldehyde values in the SB oil treatment, starting at d 10 of storage. In cooked patties, during the entire storage time, the SB oil showed the highest (P < 0.05) lipid oxidation development compared with the other treatments. Regarding vitamin E, in both fresh parts and cooked meat patties, in most sampling days the high supplemented level showed lower (P < 0.05) malonaldehyde values than the control treatment. In conclusion, the lipid oxidation stability of chicken meat is influenced by the lipid source and vitamin E level included in the diet upon storage time and processing of the meat.
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Alimentación Animal/clasificación , Pollos/fisiología , Grasas de la Dieta/farmacología , Peroxidación de Lípido/efectos de los fármacos , Carne/normas , Vitamina E/farmacología , Animales , Culinaria , Ácidos Grasos/análisis , Carne/análisis , Músculo Esquelético/efectos de los fármacos , Músculo Esquelético/fisiología , Vitamina E/sangreRESUMEN
There is an increasing demand in precooked chicken meat products for restaurants and catering services. Because cooked chicken meat develops lipid oxidation relatively fast, sous vide chicken meat was studied to assess its shelf-life. Six hundred Cobb x Ross broilers were fed for 6 wk with a basal corn-soybean meal diet including soybean, palm kernel, or animal-vegetable oil, each supplemented with 33 or 200 mg/kg of dl-alpha-tocopheryl acetate. Broilers were randomly assigned into 6 treatments and 4 repetitions with 25 birds each. Boneless breast or thigh muscle pieces were dissected into 5 x 5 x 5 cm cubes, vacuum-packed, cooked in water bath (until 74 degrees C internal temperature), chilled, and stored at 4 degrees C for 1, 5, 10, 25, and 40 d. For each storage day, each pouch contained 3 pieces of meat, either breast or thigh. Thiobarbituric acid reactive substances analysis, to quantify malonaldehyde (MDA) values, was conducted to estimate the lipid oxidation development. Nonheme iron values of cooked meat were analyzed. Fatty acid methyl esters analysis was performed in chicken muscle to determine its fatty acid composition. There was no interaction between dietary fat and vitamin E level in all of the variables studied except in nonheme iron. Dietary fat significantly influenced the fatty acid composition of the muscle (P < 0.01), but it did not affect the MDA values, regardless of differences in the muscle fatty acid composition between treatments. Supplementation of the high level of vitamin E significantly reduced the MDA values in both breast and thigh meat (P < 0.01). The maximum MDA values were observed at d 40 of storage in thigh and breast meat in animal-vegetable and soybean oil treatments with the low levels of vitamin E, 0.91 and 0.70 mg/kg, respectively. Nonheme iron values in thigh meat differed between treatments at 1 or 25 d of storage but not in breast meat. In conclusion, refrigerated sous vide chicken meat has a prolonged shelf-life, which is enhanced by dietary supranutritional supplementation of vitamin E.
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Pollos , Glycine max , Peroxidación de Lípido/efectos de los fármacos , Carne/análisis , Tocoferoles/farmacología , Vitamina E/farmacología , Animales , Culinaria , Suplementos Dietéticos , Ácidos Grasos/análisis , Aceites de Pescado/farmacología , Hierro/análisis , Lípidos/análisis , Músculo Esquelético/química , Aceites de Plantas/farmacología , alfa-Tocoferol/análisisRESUMEN
Symbioses may be important mechanisms of plant adaptation to their environment. We conducted a reciprocal inoculation experiment to test the hypothesis that soil fertility is a key driver of local adaptation in arbuscular mycorrhizal (AM) symbioses. Ecotypes of Andropogon gerardii from phosphorus-limited and nitrogen-limited grasslands were grown with all possible "home and away" combinations of soils and AM fungal communities. Our results indicate that Andropogon ecotypes adapt to their local soil and indigenous AM fungal communities such that mycorrhizal exchange of the most limiting resource is maximized. Grasses grown in home soil and inoculated with home AM fungi produced more arbuscules (symbiotic exchange structures) in their roots than those grown in away combinations. Also, regardless of the host ecotype, AM fungi produced more extraradical hyphae in their home soil, and locally adapted AM fungi were, therefore, able to sequester more carbon compared with nonlocal fungi. Locally adapted mycorrhizal associations were more mutualistic in the two phosphorus-limited sites and less parasitic at the nitrogen-limited site compared with novel combinations of plants, fungi, and soils. To our knowledge, these findings provide the strongest evidence to date that resource availability generates evolved geographic structure in symbioses among plants and soil organisms. Thus, edaphic origin of AM fungi should be considered when managing for their benefits in agriculture, ecosystem restoration, and soil-carbon sequestration.
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Ecosistema , Micorrizas/fisiología , Simbiosis/fisiología , Adaptación Biológica , Biomasa , Carbono/metabolismo , Medio Oeste de Estados Unidos , Micorrizas/crecimiento & desarrollo , Fósforo/metabolismo , Raíces de Plantas/microbiología , Poaceae/crecimiento & desarrollo , Poaceae/microbiología , Poaceae/fisiología , Suelo/análisis , Microbiología del SueloRESUMEN
Previously, in tightly controlled studies, using three independent, yet complementary techniques, we refuted the claim that a mitochondrial nitric oxide synthase (mtNOS) isoform exists within pure, rat liver mitochondria (MT). Of those techniques, the NOS-catalyzed [(14)C]-L-arginine to [(14)C]-L-citrulline conversion assay (NOS assay) with MT samples indicated a weak, radioactive signal that was NOS-independent. Aliquots of samples from the NOS assays were then extracted with acetone, separated by high performance thin-layer chromatography (HPTLC) and exposed to autoradiography. Results obtained from these samples showed no radioactive band for L-citrulline. However, a fast-migrating, diffuse, radioactive band was observed in the TLC lanes loaded with MT samples. In this manuscript, we identify and confirm that this radioactive signal in MT samples is due to the arginase-catalyzed conversion of [(14)C]-L-arginine to [(14)C]-urea. The current results, in addition to reconfirming the absence of NOS activity in rat liver MT, also show the need to include arginase inhibitors in studies using MT samples in order to avoid confounding results when using NOS activity assays.