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While considerable literature exists with respect to clinical aspects of critical care anesthesiology (CCA) practice, few publications have focused on how anesthesiology-based critical care practices are organized and the challenges associated with the administration and management of anesthesiology critical care units. Currently, numerous challenges are affecting the sustainability of CCA practice, including decreased applications to fellowship positions and decreased reimbursement for critical care work. This review describes what is known about the subspecialty of CCA and leverages the experience of administrative leaders in adult critical care anesthesiologists in the United States to describe potential solutions.
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Anestesiología , Consenso , Cuidados Críticos , Humanos , Cuidados Críticos/normas , Estados Unidos , Anestesiólogos/normasRESUMEN
Persistent tuberculosis (TB) in cattle populations in England has been associated with an exchange of infection with badgers (Meles meles). A badger control policy (BCP) commenced in 2013. Its aim was to decrease TB incidence in cattle by reducing the badger population available to provide a wildlife reservoir for bovine TB. Monitoring data from 52 BCP intervention areas 200-1600 km2 in size, starting over several years, were used to estimate the change in TB incidence rate in cattle herds, which was associated with time since the start of the BCP in each area. A difference in differences analysis addressed the non-random selection and starting sequence of the areas. The herd incidence rate of TB reduced by 56% (95% Confidence Interval 41-69%) up to the fourth year of BCP interventions, with the largest drops in the second and third years. There was insufficient evidence to judge whether the incidence rate reduced further beyond 4 years. These estimates are the most precise for the timing of declines in cattle TB associated with interventions primarily targeting badgers. They are within the range of previous estimates from England and Ireland. This analysis indicates the importance of reducing transmission from badgers to reduce the incidence of TB in cattle, noting that vaccination of badgers, fertility control and on farm biosecurity may also achieve this effect.
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Mustelidae , Mycobacterium bovis , Tuberculosis Bovina , Animales , Bovinos , Tuberculosis Bovina/epidemiología , Tuberculosis Bovina/prevención & control , Inglaterra/epidemiología , Políticas , Reservorios de Enfermedades/veterinariaRESUMEN
PURPOSE: The data resulting from epilepsy surgical evaluation are occasionally unclear in cases of mesial temporal lobe (MTL) epilepsy. Long-term intracranial EEG (iEEG) collected by the Responsive Neurostimulation (RNS) System may be an approach for capturing additional seizure data while treating patients with neurostimulation. We reviewed iEEG seizure lateralization and clinical outcomes in bilateral MTL patients at University of Utah. METHODS: Long-term RNS System iEEG seizure lateralization was compared with pre-RNS System lateralization obtained during surgical evaluation. Safety and clinical outcomes were extracted retrospectively from patient records. RESULTS: Twenty-six patients received an RNS System with bilateral MTL leads. Fifteen of the patients had adequate follow-up to report clinical outcomes (>1 year), and 25 patients had enough recorded data (>6 months) to perform iEEG analysis. Median percent reduction in clinical seizures at last follow-up was 58%, and 40% reported being seizure-free at last follow-up, for variable durations. The electrographic seizure lateralization (unilateral vs. bilateral) differed between surgical evaluation and long-term iEEG in 44% of our patients. In the subset of eight patients (32%) who had only unilateral seizures recorded during surgical evaluation, but were implanted with bilateral MTL leads based on bilateral interictal epileptiform discharges, 62% (5/8) had bilateral seizures recorded on long-term iEEG. Interestingly, in the 18 patients who had bilateral seizures recorded during surgical evaluation, 28% (5/18) were found to be unilateral on long-term iEEG. CONCLUSIONS: Our data suggest that RNS System implantation in suspected bilateral MTL cases may be an option to assess a patient's true seizure lateralization on long-term iEEG. Responsive neuromodulation should be considered before resection or ablation in cases that have evaluation data suggesting bilaterality.
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Full-thickness burns damage all layers of skin and may also damage underlying tissue including bones, muscles, and tendons. Full-thickness burns almost always require immediate medical and surgical management. Some may require extensive bone, muscular, and other reconstructive surgery depending on the depth of involvement of surrounding tissues. Bone exposure in burn patients can lead to unique complications including osteomyelitis. We present the case of an elderly patient with a history of dementia who presented with full-thickness burns to the back with exposed spinal elements who later developed osteomyelitis requiring lumbar spine reconstruction with bilateral paraspinous muscle flap for back reconstruction, adjacent tissue transfer, and split thickness skin grafting. This case represents the severity of full-thickness burns with underlying bone exposure and the importance of aggressive wound care and multidisciplinary team approach.
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Promising biomaterials should be tested in appropriate large animal models that recapitulate human inflammatory and regenerative responses. Previous studies have shown tyrosine-derived polycarbonates (TyrPC) are versatile biomaterials with a wide range of applications across multiple disciplines. The library of TyrPC has been well studied and consists of thousands of polymer compositions with tunable mechanical characteristics and degradation and resorption rates that are useful for nerve guidance tubes (NGTs). NGTs made of different TyrPCs have been used in segmental nerve defect models in small animals. The current study is an extension of this work and evaluates NGTs made using two different TyrPC compositions in a 1 cm porcine peripheral nerve repair model. We first evaluated a nondegradable TyrPC formulation, demonstrating proof-of-concept chronic regenerative efficacy up to 6 months with similar nerve/muscle electrophysiology and morphometry to the autograft repair control. Next, we characterized the acute regenerative response using a degradable TyrPC formulation. After 2 weeks in vivo, TyrPC NGT promoted greater deposition of pro-regenerative extracellular matrix (ECM) constituents (in particular collagen I, collagen III, collagen IV, laminin, and fibronectin) compared to commercially available collagen-based NGTs. This corresponded with dense Schwann cell infiltration and axon extension across the lumen. These findings confirmed results reported previously in a mouse model and reveal that TyrPC NGTs were well tolerated in swine and facilitated host axon regeneration and Schwann cell infiltration in the acute phase across segmental defects - likely by eliciting a favorable neurotrophic ECM milieu. This regenerative response ultimately can contribute to functional recovery.
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Regeneración Tisular Dirigida/métodos , Regeneración Nerviosa , Traumatismos de los Nervios Periféricos/terapia , Cemento de Policarboxilato/química , Andamios del Tejido/química , Tirosina/química , Animales , Matriz Extracelular/metabolismo , Nervio Peroneo/lesiones , Nervio Peroneo/metabolismo , Nervio Peroneo/fisiología , Células de Schwann/citología , Células de Schwann/metabolismo , PorcinosRESUMEN
The cardioprotective effects of ginseng root extracts have been reported. However, nothing is known about the myocardial actions of the phenolic compounds enriched in ginseng berry. Therefore, this study was undertaken to investigate the effects of American ginseng berry extract (GBE) in an experimental model of myocardial infarction (MI). Coronary artery ligation was performed on Spragueâ»Dawley male rats to induce MI after which animals were randomized into groups receiving either distilled water or GBE intragastrically for 8 weeks. Echocardiography and assays for malondialdehyde (MDA) and TNF-α were conducted. Flow cytometry was used to test the effects of GBE on T cell phenotypes and cytokine production. Although GBE did not improve the cardiac functional parameters, it significantly attenuated oxidative stress in post-MI rat hearts. GBE treatment also resulted in lower than control levels of TNF-α in post-MI rat hearts indicating a strong neutralizing effect of GBE on this cytokine. However, there was no effect of GBE on the proportion of different T cell subsets or ex-vivo cytokine production. Taken together, the present study demonstrates GBE reduces oxidative stress, however no effect on cardiac structure and function in post-MI rats. Moreover, reduction of TNF-α levels below baseline raises concern regarding its use as prophylactic or preventive adjunct therapy in cardiovascular disease.
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Frutas/química , Infarto del Miocardio/tratamiento farmacológico , Infarto del Miocardio/fisiopatología , Estrés Oxidativo , Panax/química , Fenoles/uso terapéutico , Remodelación Ventricular , Animales , Antioxidantes/farmacología , Antioxidantes/uso terapéutico , Peso Corporal/efectos de los fármacos , Cardiomegalia/tratamiento farmacológico , Cardiomegalia/fisiopatología , Citocinas/biosíntesis , Diástole , Pruebas de Función Cardíaca , Inmunofenotipificación , Inflamación/patología , Masculino , Infarto del Miocardio/patología , Miocardio/patología , Tamaño de los Órganos/efectos de los fármacos , Fenoles/farmacología , Ratas Sprague-Dawley , Remodelación Ventricular/efectos de los fármacosRESUMEN
The role of microbial secondary metabolites in the ecology of the organisms that produce them remains poorly understood. Variation in aflatoxin production by Aspergillus flavus is maintained by balancing selection, but the ecological function and impact on fungal fitness of this compound are unknown. We hypothesize that balancing selection for aflatoxin production in A. flavus is driven by interaction with insects. To test this, we competed naturally occurring aflatoxigenic and non-aflatoxigenic fungal isolates against Drosophila larvae on medium containing 0-1750 ppb aflatoxin, using quantitative PCR to quantify A. flavus DNA as a proxy for fungal fitness. The addition of aflatoxin across this range resulted in a 26-fold increase in fungal fitness. With no added toxin, aflatoxigenic isolates caused higher mortality of Drosophila larvae and had slightly higher fitness than non-aflatoxigenic isolates. Additionally, aflatoxin production increased an average of 1.5-fold in the presence of a single larva and nearly threefold when the fungus was mechanically damaged. We argue that the role of aflatoxin in protection from fungivory is inextricably linked to its role in interference competition. Our results, to our knowledge, provide the first clear evidence of a fitness advantage conferred to A. flavus by aflatoxin when interacting with insects.
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Aflatoxinas/metabolismo , Aspergillus flavus/química , Aspergillus flavus/genética , Drosophila melanogaster/fisiología , Herbivoria , Selección Genética , Animales , Drosophila melanogaster/crecimiento & desarrollo , Microbiología de Alimentos , Larva/crecimiento & desarrollo , Larva/fisiologíaRESUMEN
Aflatoxin is a liver carcinogen, and rapid, inexpensive methods to detect its urinary biomarkers are needed. We used a commercial enzyme-linked immuno-sorbent assay (ELISA) for aflatoxin M1 in urine (Helica Biosystems) to test 52 Haitian samples. Using this ELISA, we detected traces above the limit of detection (0.2 ng/ml urine) but below the limit of quantitation (0.4 ng/ml) in 14 samples. Liquid chromatography of all 52 Haitian urine samples revealed that only 11 had quantifiable AFM1 (mean: 29.5 pg/ml, standard error: 10.8, range: 2.94-96.5 pg/ml). The Helica ELISA may have detected forms of aflatoxin other than AFM1 in the Haitian samples, or matrix enhancement may have affected results at low AFM1 concentrations. This ELISA may serve as an initial, qualitative indicator of aflatoxin exposure for epidemiological purposes. But this method's utility as a precise and specific indicator of AFM1 concentrations will require additional refinement and validation.
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Aflatoxina M1/orina , Juego de Reactivos para Diagnóstico/normas , Carcinógenos/análisis , Cromatografía Líquida de Alta Presión/métodos , Ensayo de Inmunoadsorción Enzimática/métodos , Haití , Humanos , Límite de Detección , Neoplasias Hepáticas/etiología , Sensibilidad y EspecificidadRESUMEN
Aflatoxins (AFs) are hepatocarcinogenic mycotoxins that can contaminate grains and oil seeds in tropical and sub-tropical areas and have been detected in maize and peanut products of Haiti. The first objective was to assess human exposure to AFs among Haitians at an urban hospital (GHESKIO) and a rural health centre (HCBH). The second objective was to test the association between AF exposure and reported dietary intake of potentially contaminated foods, such as maize, peanut products and milk. Measurement of urinary AFM1 by HPLC revealed that among 367 participants 14% and 22% at GHESKIO and HCBH, respectively, had detectable AFM1. The maximum and median AFM1 concentrations for all detected samples were 700 pg AFM1 ml(-1) and 11.7 pg ml(-1), respectively. Detection of AFM1 was significantly associated with peanut consumption (p < 0.05). Controlling for diet and age group in a logit model, patients who reported peanut consumption the day of the survey and patients from HCBH had greater log odds of excreting detectable AFM1 (p < 0.001 and 0.002, respectively); females had lower log odds (p = 0.020). Recalled frequency of consuming non-dairy animal-sourced foods, an indicator of diet quality, approached significance (p = 0.056) as an inverse predictor of urinary AFM1 detection. The findings augur the need for interventions that will improve food safety in Haiti and limit exposure to AFs, particularly among rural communities.
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Aflatoxina M1/orina , Dieta , Población Rural , Población Urbana , Adolescente , Adulto , Animales , Arachis , Carcinógenos , Niño , Preescolar , Cromatografía Líquida de Alta Presión , Estudios Transversales , Encuestas sobre Dietas , Femenino , Contaminación de Alimentos/análisis , Haití , Humanos , Lactante , Masculino , Leche , Zea maysRESUMEN
Electronic Bingo games have recently appeared in Ontario Charitable Gaming Centres. Here we summarize the characteristics of this novel form of electronic gambling, and give a detailed characterization of one game. We contend that these games have structural characteristics that make them similar to modern Electronic Gaming Machines (EGMs) that feature multiline slots games. These features include a fast and continuous gaming experience, with player adjustable win size and reinforcement rate, a high frequency of losses disguised as wins, and highly salient near misses. Some of these games also have bonus rounds and provide players with a list of recent wins. We conclude that provincial and state gaming authorities should be aware that the placement of Bingo EGMs in existing Bingo facilities may increase problem gambling among an already well-established community of Bingo enthusiasts.
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An improved "dilute and shoot" LC-MS/MS multibiomarker approach was used to monitor urinary excretion of 23 mycotoxins and their metabolites in human populations from Asia (Bangladesh), Europe (Germany), and the Caribbean region (Haiti). Deoxynivalenol (DON), deoxynivalenol-3-glucuronide (DON-3-GlcA), T-2-toxin (T-2), HT-2-toxin (HT-2), HT-2-toxin-4-glucuronide (HT-2-4-GlcA), fumonisin B1 (FB1), aflatoxins (AFB1, AFB2, AFG1, AFG2, AFM1), zearalenone (ZEA), zearalanone (ZAN), their urinary metabolites α-zearalanol (α-ZEL) and ß-zearalanol (ß-ZEL), and corresponding 14-O-glucuronic acid conjugates (ZEA-14-GlcA, ZAN-14-GlcA, ß-ZEL, α/ß-ZEL-14-GlcA), ochratoxin A (OTA), and ochratoxin alpha (OTα) as well as enniatin B (EnB) and dihydrocitrinone (DH-CIT) were among these compounds. Eight urinary mycotoxin biomarkers were detected (AFM1, DH-CIT, DON, DON-GLcA, EnB, FB1, OTA, and α-ZEL). DON and DON-GlcA were exclusively detected in urines from Germany and Haiti whereas urinary OTA and DH-CIT concentrations were significantly higher in Bangladeshi samples. AFM1 was present in samples from Bangladesh and Haiti only. Exposure was estimated by the calculation of probable daily intakes (PDI), and estimates suggested occasional instances of toxin intakes that exceed established tolerable daily intakes (TDI). The detection of individual mycotoxin exposure by biomarker-based approaches is a meaningful addition to the classical monitoring of the mycotoxin content of the food supply.
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Biomarcadores/orina , Micotoxinas/orina , Bangladesh , Cromatografía Líquida de Alta Presión/métodos , Exposición a Riesgos Ambientales , Contaminación de Alimentos/análisis , Alemania , Haití , Humanos , Espectrometría de Masas en Tándem/métodosRESUMEN
OBJECTIVES: The purpose of this study is to determine the trajectory of lung function change after exposure cessation to occupational organic dust exposure, and to identify factors that modify improvement. METHODS: The Shanghai Textile Worker Study is a longitudinal study of 447 cotton workers exposed to endotoxin-containing dust and 472 silk workers exposed to non-endotoxin-containing dust. Spirometry was performed at 5-year intervals. Air sampling was performed to estimate individual cumulative exposures. The effect of work cessation on forced expiratory volume in 1 s (FEV1) was modelled using generalised additive mixed effects models to identify the trajectory of FEV1 recovery. Linear mixed effects models incorporating interaction terms were used to identify modifiers of FEV1 recovery. Loss to follow-up was accounted for with inverse probability of censoring weights. RESULTS: 74.2% of the original cohort still alive participated in 2011. Generalised additive mixed models identified a non-linear improvement in FEV1 for all workers after exposure cessation, with no plateau noted 25 years after retirement. Linear mixed effects models incorporating interaction terms identified prior endotoxin exposure (p=0.01) and male gender (p=0.002) as risk factors for impaired FEV1 improvement after exposure cessation. After adjusting for gender, smoking delayed the onset of FEV1 gain but did not affect the overall magnitude of change. CONCLUSIONS: Lung function improvement after cessation of exposure to organic dust is sustained. Endotoxin exposure and male gender are risk factors for less FEV1 improvement.
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Contaminantes Ocupacionales del Aire/efectos adversos , Polvo , Endotoxinas/efectos adversos , Pulmón/efectos de los fármacos , Exposición Profesional/efectos adversos , Recuperación de la Función , Industria Textil , China , Empleo , Femenino , Estudios de Seguimiento , Volumen Espiratorio Forzado , Humanos , Estudios Longitudinales , Pulmón/fisiopatología , Enfermedades Pulmonares/fisiopatología , Enfermedades Pulmonares/rehabilitación , Masculino , Enfermedades Profesionales/fisiopatología , Enfermedades Profesionales/rehabilitación , Factores de Riesgo , Fumar , TextilesRESUMEN
UNLABELLED: Nitrogen regulation in Escherichia coli is a model system for gene regulation in bacteria. Growth on glutamine as a sole nitrogen source is assumed to be nitrogen limiting, inferred from slow growth and strong NtrB/NtrC-dependent gene activation. However, we show that under these conditions, the intracellular glutamine concentration is not limiting but 5.6-fold higher than in ammonium-replete conditions; in addition, α-ketoglutarate concentrations are elevated. We address this glutamine paradox from a systems perspective. We show that the dominant role of NtrC is to regulate glnA transcription and its own expression, indicating that the glutamine paradox is not due to NtrC-independent gene regulation. The absolute intracellular NtrC and GS concentrations reveal molecular control parameters, where NtrC-specific activities were highest in nitrogen-starved cells, while under glutamine growth, NtrC showed intermediate specific activity. We propose an in vivo model in which α-ketoglutarate can derepress nitrogen regulation despite nitrogen sufficiency. IMPORTANCE: Nitrogen is the most important nutrient for cell growth after carbon, and its metabolism is coordinated at the metabolic, transcriptional, and protein levels. We show that growth on glutamine as a sole nitrogen source, commonly assumed to be nitrogen limiting and used as such as a model system for nitrogen limitation, is in fact nitrogen replete. Our integrative quantitative analysis of key molecules involved in nitrogen assimilation and regulation reveal that glutamine is not necessarily the dominant molecule signaling nitrogen sufficiency and that α-ketoglutarate may play a more important role in signaling nitrogen status. NtrB/NtrC integrates α-ketoglutarate and glutamine signaling--sensed by the UTase (glnD) and PII (glnB), respectively--and regulates the nitrogen response through self-regulated expression and phosphorylation-dependent activation of the nitrogen (ntr) regulon. Our findings support α-ketoglutarate acting as a global regulatory metabolite.
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Carbono/metabolismo , Proteínas de Escherichia coli/metabolismo , Escherichia coli/genética , Escherichia coli/metabolismo , Regulación Bacteriana de la Expresión Génica , Nitrógeno/metabolismo , Proteínas PII Reguladoras del Nitrógeno/metabolismo , Factores de Transcripción/metabolismo , Transcripción Genética , Compuestos de Amonio/metabolismo , Glutamina/metabolismoRESUMEN
BACKGROUND: Ginseng including North American ginseng (Panax quinquefolius L.) is one of the most widely used medicinal plants. Its success is thought to be due to a diverse collection of ginsenosides that serve as its major bioactive compounds. However, few genomic resources exist and the details concerning its various biosynthetic pathways remain poorly understood. As the root is the primary tissue harvested commercially for ginsenosides, next generation sequencing was applied to the characterization and assembly of the root transcriptome throughout seasonal development. Transcripts showing homology to ginsenoside biosynthesis enzymes were profiled in greater detail. RESULTS: RNA extracts from root samples from seven development stages of North American ginseng were subjected to 454 sequencing, filtered for quality and used in the de novo assembly of a collective root reference transcriptome consisting of 41,623 transcripts. Annotation efforts using a number of public databases resulted in detailed annotation information for 34,801 (84%) transcripts. In addition, 3,955 genes were assigned to metabolic pathways using the Kyoto Encyclopedia of Genes and Genomes. Among our results, we found all of the known enzymes involved in the ginsenoside backbone biosynthesis and used co-expression analysis to identify a number of candidate sequences involved in the latter stages ginsenoside biosynthesis pathway. Transcript profiles suggest ginsenoside biosynthesis occurs at distinct stages of development. CONCLUSIONS: The assembly generated provides a comprehensive annotated reference for future transcriptomic study of North American ginseng. A collection of putative ginsenoside biosynthesis genes were identified and candidate genes predicted from the lesser understood downstream stages of biosynthesis. Transcript expression profiles across seasonal development suggest a primary dammarane-type ginsenoside biosynthesis occurs just prior to plant senescence, with secondary ginsenoside production occurring throughout development. Data from the study provide a valuable resource for conducting future ginsenoside biosynthesis research in this important medicinal plant.
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Perfilación de la Expresión Génica , Panax/crecimiento & desarrollo , Panax/genética , Raíces de Plantas/crecimiento & desarrollo , Raíces de Plantas/genética , Estaciones del Año , Bases de Datos Genéticas , Anotación de Secuencia Molecular , ARN Mensajero/genética , Análisis de SecuenciaRESUMEN
Food and yard wastes are available year round at low cost and have the potential to complement each other for SS-AD. The goal of this study was to determine optimal feedstock/effluent (F/E) and food waste/yard waste mixing ratios for optimal biogas production. Co-digestion of yard and food waste was carried out at F/E ratios of 1, 2, and 3. For each F/E ratio, food waste percentages of 0%, 10%, and 20%, based on dry volatile solids, were evaluated. Results showed increased methane yields and volumetric productivities as the percentage of food waste was increased to 10% and 20% of the substrate at F/E ratios of 2 and 1, respectively. This study showed that co-digestion of food waste with yard waste at specific ratios can improve digester operating characteristics and end performance metrics over SS-AD of yard waste alone.
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Bacterias Anaerobias/metabolismo , Biocombustibles , Reactores Biológicos , Alimentos , Metano/biosíntesis , Poaceae/metabolismo , Residuos , Análisis de Varianza , Cromatografía Líquida de Alta Presión , Poaceae/químicaRESUMEN
The use of (1)H-NMR-based metabolomics to distinguish and identify unique markers of five Ontario ginseng (Panax quinquefolius L.) landraces and two ginseng species (P. quinquefolius and P. ginseng) was evaluated. Three landraces (2, 3, and 5) were distinguished from one another in the principal component analysis (PCA) scores plot. Further analysis was conducted and specific discriminating metabolites from the PCA loadings were determined. Landraces 3 and 5 were distinguishable on the basis of a decreased NMR intensity in the methyl ginsenoside region, indicating decreased overall ginsenoside levels. In addition, landrace 5 was separated by an increased amount of sucrose relative to the rest of the landraces. Landrace 2 was separated from the rest of the landraces by the increased level of ginsenoside R(b1). The Ontario P. quinquefolius was also compared with Asian P. ginseng by PCA, and clear separation between the two groups was detected in the PCA scores plot. The PCA loadings plot and a t-test NMR difference plot were able to identify an increased level of maltose and a decreased level of sucrose in the Asian ginseng compared with the Ontario ginseng. An overall decrease of ginsenoside content, especially ginsenoside R(b1), was also detected in the Asian ginseng's metabolic profile. This study demonstrates the potential of NMR-based metabolomics as a powerful high-throughput technique in distinguishing various closely related ginseng landraces and its ability to identify metabolic differences from Ontario and Asian ginseng. The results from this study will allow better understanding for quality assessment, species authentication, and the potential for developing a fully automated method for quality control.
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Ginsenósidos/aislamiento & purificación , Espectroscopía de Resonancia Magnética/métodos , Metabolómica , Panax/química , Raíces de Plantas/química , Cromatografía Líquida de Alta Presión , Ginsenósidos/clasificación , Maltosa/análisis , Espectrometría de Masas , Panax/clasificación , Panax/metabolismo , Raíces de Plantas/metabolismo , Análisis de Componente Principal , Sacarosa/análisisRESUMEN
Lignocellulosic biomass feedstocks (switchgrass, corn stover, wheat straw, yard waste, leaves, waste paper, maple, and pine) were evaluated for methane production under liquid anaerobic digestion (L-AD) and solid-state anaerobic digestion (SS-AD). No significant difference in methane yield between L-AD and SS-AD, except for waste paper and pine, were found. However, the volumetric productivity was 2- to 7-fold greater in the SS-AD system compared with the L-AD system, except for paper. Methane yields from corn stover, wheat straw, and switchgrass were 2-5 times higher than those from yard waste, maple, and pine biomass. Waste paper had a methane yield of only 15 L/kg VS caused by souring during SS-AD due to organic overloading. Pine also had very low biogas yield of 17 L/kg VS, indicating the need for pretreatment prior to SS-AD. The findings of this study can guide future studies to improve the efficiency and stability of SS-AD of lignocellulosic biomass.
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Biocombustibles , Lignina/metabolismo , Anaerobiosis , Biomasa , Reactores Biológicos , Hidrólisis , Cinética , Metano/metabolismoRESUMEN
Cisplatin is a widely used antineoplastic agent. However, its major limitation is dose-dependent nephrotoxicity whose precise mechanism is poorly understood. Recent studies have suggested that mitochondrial dysfunction in tubular epithelium contributes to cisplatin-induced nephrotoxicity. Here the authors extend those findings by describing the role of an important electron transport chain enzyme, cytochrome c oxidase (COX). Immunohistochemistry for COX 1 protein demonstrated that, in response to cisplatin, expression was mostly maintained in focally damaged tubular epithelium. In contrast, COX enzyme activity in proximal tubules (by light microscopy) was decreased. Ultrastructural analysis of the cortex and outer stripe of the outer medulla showed decreased mitochondrial mass, disruption of cristae, and extensive mitochondrial swelling in proximal tubular epithelium. Functional electron microscopy showed that COX enzyme activity was decreased in the remaining mitochondria in the proximal tubules but maintained in distal tubules. In summary, cisplatin-induced nephrotoxicity is associated with structural and functional damage to the mitochondria. More broadly, using functional electron microscopy to measure mitochondrial enzyme activity may generate mechanistic insights across a spectrum of renal disorders.
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Lesión Renal Aguda/inducido químicamente , Cisplatino/toxicidad , Complejo IV de Transporte de Electrones/metabolismo , Túbulos Renales Proximales/efectos de los fármacos , Túbulos Renales Proximales/patología , Mitocondrias/efectos de los fármacos , Mitocondrias/enzimología , Lesión Renal Aguda/metabolismo , Lesión Renal Aguda/patología , Animales , Complejo IV de Transporte de Electrones/antagonistas & inhibidores , Inmunohistoquímica , Túbulos Renales Proximales/metabolismo , Masculino , Ratones , Ratones Endogámicos C57BL , Mitocondrias/patología , Especies Reactivas de Oxígeno/metabolismoRESUMEN
Edible fruits of the native South American tree Melicoccus bijugatus Jacq. are consumed fresh or in traditional food, drink and medicinal preparations. Some therapeutic effects of these fruits may be due to phenolics and sugars. Aqueous acetone, methanol or ethanol tissue extracts of different cultivars or collections of M. bijugatus fruits from the Dominican Republic and Florida were analyzed for total phenolics and free radical scavenging activity by UV-vis spectroscopy, sugars by gas chromatography, and antimicrobial activity by the disc diffusion assay. Total phenolics and free radical scavenging activities ranked: seed coat > embryo > pulp extracts. Montgomery cultivar fruits had the highest total phenolics. For sugars: pulp > embryo and highest in Punta Cana fruit pulp. In all extracts: sucrose > glucose and fructose. Glucose:fructose ratios were 1:1 (pulp) and 0.2:1 (embryo). Pulp extracts had dose-response antibacterial activity and pulp and embryo extracts had antifungal activity against one yeast species. Phenolics and sugars were confirmed with thin-layer chromatography and nuclear magnetic resonance. Sugar-free pulp fractions containing phenolics had slightly more antimicrobial activity than H2O-soluble pulp fractions with sugars. Results indicate M. bijugatus fruits contain phenolics, sugars and other H2O-soluble compounds consistent with therapeutic uses.