Growth factors for clinical-scale expansion of human articular chondrocytes : Relevance for automated bioreactor systems

The expansion of chondrocytes in automated bioreactors for clinical use requires that a relevant number of cells be generated, starting from variable initial seeding densities in one passage and using autologous serum. We investigated whether the growth factor combination transforming growth factor beta 1/fibroblast growth factor 2/platelet-derived growth factor BB (TFP), recently shown to enhance the proliferation capacity of human articular chondrocytes (HACs), allows the efficiency of chondrocyte use to be increased at different seeding densities and percentages of human serum (HS). HACs were seeded at 1,000, 5,000, and 10,000 celIS/cm(2) in medium containing 10 bovine serum or 10,000 cells/cm(2) with 1 chondrogenic capacity of post-expanded HACs was then assessed in pellet cultures. Expansion with TFP allowed a sufficient number of HACs to be obtained in one passage even at the lowest seeding density and HS percentage and variability in cartilage-forming capacity of HACs expanded under the different conditions to be reduced. Instead, larger variations and insufficient yields were found in the absence of TFP. By allowing large numbers of cells to be obtained, starting from a wide range of initial seeding densities and HS percentages, the use of TFP may represent a viable solution for the efficient expansion of HACs and addresses constraints of automated clinical bioreactor systems

Componentes menores y estabilidad a la oxidación mediante DSC de aceite de colza fraccionado y estructurado mediante catálisis con lipasa

Natural fats and oils can be modified by various methods to prepare products with desired physical, chemical and nutritional properties. The enrichment and retention of the minor lipid components, the incorporation of capric acid and oxidative stability in low temperature fractionated rapeseed oil (RSO) in acetone were assessed in this study. The fractionated liquid part (L-RSO), the solid part (S-RSO) and the RSO were transesterified with capric acid (CA) at different mole ratios using lipase. The yields of L-RSO and S-RSO were 30 and 70 g per 100 g, respectively. The L-RSO contained higher levels of linoleic acid and linolenic acid, and a lower level of oleic acid compared to the S-RSO. The S-RSO contained a higher amount of total sterols than the RSO and the L-RSO. In contrast, the L-RSO contained a higher amount of total tocopherols than the RSO and the S-RSO. The incorporation of CA was ideal at a mole ratio of 1:3. The content of sterols and tocopherols gradually decreased with an increased mole ratio for the CA incorporation. The oxidative stability shown as onset temperature, determined by DSC, of the S-RSO was higher compared to those of the L-RSO and RSO.Las grasas y aceites naturales pueden ser modificados mediante diversos métodos para preparar productos con propiedades físicas, químicas y nutricionales deseadas. El enriquecimiento y la retención de componentes lipídicos menores, la incorporación de ácido cáprico y estabilidad a la oxidación a baja temperatura de aceites de colza (RSO) fraccionado en acetona, se evaluaron en este estudio. La fracción líquida (L-RSO), la fracción sólida (S-RSO) y el RSO son transesterificados con ácido cáprico (CA) en diversas relaciones molares utilizando lipasa. Los rendimientos de las fracciones L-RSO y RSO-S fueron de 30 y 70 g por 100 g, respectivamente. La fracción líquida L-RSO contenía un mayor nivel de los ácidos linoleico y linolénico, y un menor nivel de ácido oleico en comparación con la fracción sólida S-RSO. La fracción sólida S-RSO tiene mayor contenido total de esteroles que RSO y que L-RSO. En contraste, la fracción L-RSO contenía mayor contenido de tocoferoles totales que RSO y que S-RSO. La incorporación de CA fue excelente con una relación molar de 1:3. El contenido de esteroles y tocoferoles disminuyó gradualmente con un incremento de la relación molar de la incorporación de CA. La estabilidad oxidativa muestra cómo la temperatura de inicio, determinada mediante DSC, de la fracción S-RSO fue mayor en comparación con la de la L-RSO y RSO

Quantifying Grassland-to-Woodland Transitions and the Implications for Carbon and Nitrogen Dynamics in the Southwest United States

Replacement of grasslands and savannas by shrublands and woodlands has been widely reported in tropical, temperate and high-latitude rangelands worldwide (Archer 1994). These changes in vegetation structure may reflect historical shifts in climate and land use; and are likely to influence biodiversity, productivity, above- and below ground carbon and nitrogen sequestration and biophysical aspects of land surface-atmosphere interactions. The goal of our proposed research is to investigate how changes in the relative abundance of herbaceous and woody vegetation affect carbon and nitrogen dynamics across heterogeneous savannas and shrub/woodlands. By linking actual land-cover composition (derived through spectral mixture analysis of AVIRIS, TM, and AVHRR imagery) with a process-based ecosystem model, we will generate explicit predictions of the C and N storage in plants and soils resulting from changes in vegetation structure. Our specific objectives will be to (1) continue development and test applications of spectral mixture analysis across grassland-to-woodland transitions; (2) quantify temporal changes in plant and soil C and N storage and turnover for remote sensing and process model parameterization and verification; and (3) couple landscape fraction maps to an ecosystem simulation model to observe biogeochemical dynamics under changing landscape structure and climatological forcings

Previous antibiotic exposure increases risk of infection with extended-spectrum-β-lactamase- and AmpC-producing Escherichia coli and Klebsiella pneumoniae in pediatric patients

The objective of this study was to determine whether antibiotic exposure is associated with extended-spectrum-beta-lactamase- or AmpC-producing Escherichia coli or Klebsiella pneumoniae infections in children. We collected extended-spectrum-beta-lactamase- or AmpC-producing E. coli or K. pneumoniae isolates and same-species susceptible controls from normally sterile sites of patients aged ≤21 years, along with associated clinical data, at four free-standing pediatric centers. After controlling for potential confounders, the relative risk of having an extended-spectrum-beta-lactamase-producing isolate rather than a susceptible isolate was 2.2 times higher (95% confidence interval [CI], 1.49 to 3.35) among those with antibiotic exposure in the 30 days prior to infection than in those with no antibiotic exposure. The results were similar when analyses were limited to exposure to third-generation cephalosporins, other broad-spectrum beta-lactams, or trimethoprim-sulfamethoxazole. Conversely, the relative risk of having an AmpC-producing versus a susceptible isolate was not significantly elevated with any antibiotic exposure in the 30 days prior to infection (adjusted relative risk ratio, 1.12; 95% CI, 0.65 to 1.91). However, when examining subgroups of antibiotics, the relative risk of having an AmpC-producing isolate was higher for patients with exposure to third-generation cephalosporins (adjusted relative risk ratio, 4.48; 95% CI, 1.75 to 11.43). Dose-response relationships between antibiotic exposure and extended-spectrum-beta-lactamase-producing or AmpC-producing isolates were not demonstrated. These results reinforce the need to study and implement pediatric antimicrobial stewardship strategies, and they indicate that epidemiological studies of third-generation cephalosporin-resistant E. coli and K. pneumoniae isolates should include resistance mechanisms when possible

Clinical effectiveness of a sedation protocol minimizing benzodiazepine infusions and favoring early dexmedetomidine: A before-after study

INTRODUCTION: Randomized controlled trials suggest clinical outcomes may be improved with dexmedetomidine as compared to benzodiazepines, however further study and validation is needed. The objective of this study was to determine the clinical effectiveness of a sedation protocol minimizing benzodiazepine use in favor of early dexmedetomidine. METHODS: This was a before-after study including adult surgical and medical ICU patients requiring mechanical ventilation and continuous sedation for at least 24 hours. The before phase included consecutive patients admitted between April 1 and August 31, 2011. Subsequently, the protocol was modified to minimize use of benzodiazepines in favor of early dexmedetomidine through a multidisciplinary approach and staff education was provided. The after phase included consecutive eligible patients between May 1 and October 31, 2012. RESULTS: 199 patients were included, with 97 patients in the before and 102 in the after phase. Baseline characteristics were well balanced between groups. Use of midazolam as initial sedation (58% vs. 27%, p \u3c 0.0001) or at any point during the ICU stay (76% vs. 48%, p \u3c 0.0001) was significantly reduced in the after phase. Dexmedetomidine use as initial sedation (2% vs. 39%, p \u3c 0.0001) or at any point during the ICU stay (39% vs. 82%, p \u3c 0.0001) significantly increased. Both the prevalence (81% vs. 93%, p =0.013) and median percent of days with delirium (55% (IQR 18-83) vs. 71% (IQR 45-100), p = 0.001) were increased in the after phase. The median duration of mechanical ventilation was significantly reduced in the after phase (110 (IQR 59-192) vs. 74.5 (IQR 42-148) hrs, p = 0.029) and significantly fewer patients required tracheostomy (20% vs. 9%, p = 0.040). The median ICU length of stay was 8 (IQR 4-12) days in the before phase and 6 (IQR 3-11) days in the after phase (p = 0.252). CONCLUSIONS: Implementing a sedation protocol that targeted light sedation and reduced benzodiazepine use led to significant improvements in the duration of mechanical ventilation and requirement for tracheostomy despite increases in the prevalence and duration of ICU delirium

The half-painted picture: Reviewing the mental health impacts of cancer screening

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Free energy barrier for melittin reorientation from a membrane-bound state to a transmembrane state

An important step in a phospholipid membrane pore formation by melittin antimicrobial peptide is a reorientation of the peptide from a surface into a transmembrane conformation. In this work we perform umbrella sampling simulations to calculate the potential of mean force (PMF) for the reorientation of melittin from a surface-bound state to a transmembrane state and provide a molecular level insight into understanding peptide and lipid properties that influence the existence of the free energy barrier. The PMFs were calculated for a peptide to lipid (P/L) ratio of 1/128 and 4/128. We observe that the free energy barrier is reduced when the P/L ratio increased. In addition, we study the cooperative effect; specifically we investigate if the barrier is smaller for a second melittin reorientation, given that another neighboring melittin was already in the transmembrane state. We observe that indeed the barrier of the PMF curve is reduced in this case, thus confirming the presence of a cooperative effect

Workforce Projections 2010-2020: Annual Supply and Demand Forecasting Models for Physical Therapists Across the United States

BACKGROUND: Health human resources continue to emerge as a critical health policy issue across the United States. OBJECTIVE: The purpose of this study was to develop a strategy for modeling future workforce projections to serve as a basis for analyzing annual supply of and demand for physical therapists across the United States into 2020. DESIGN: A traditional stock-and-flow methodology or model was developed and populated with publicly available data to produce estimates of supply and demand for physical therapists by 2020. METHODS: Supply was determined by adding the estimated number of physical therapists and the approximation of new graduates to the number of physical therapists who immigrated, minus US graduates who never passed the licensure examination, and an estimated attrition rate in any given year. Demand was determined by using projected US population with health care insurance multiplied by a demand ratio in any given year. The difference between projected supply and demand represented a shortage or surplus of physical therapists. RESULTS: Three separate projection models were developed based on best available data in the years 2011, 2012, and 2013, respectively. Based on these projections, demand for physical therapists in the United States outstrips supply under most assumptions. LIMITATIONS: Workforce projection methodology research is based on assumptions using imperfect data; therefore, the results must be interpreted in terms of overall trends rather than as precise actuarial data-generated absolute numbers from specified forecasting. CONCLUSIONS: Outcomes of this projection study provide a foundation for discussion and debate regarding the most effective and efficient ways to influence supply-side variables so as to position physical therapists to meet current and future population demand. Attrition rates or permanent exits out of the profession can have important supply-side effects and appear to have an effect on predicting future shortage or surplus of physical therapists

Citizen Science in Archaeology : Developing a Collaborative Web Service for Archaeological Finds in Finland

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