Amination of enzymes to improve biocatalyst performance: coupling genetic modification and physicochemical tools

Improvement of the features of an enzyme is in many instances a pre-requisite for the industrial implementation of these exceedingly interesting biocatalysts. To reach this goal, the researcher may utilize different tools. For example, amination of the enzyme surface produces an alteration of the isoelectric point of the protein along with its chemical reactivity (primary amino groups are the most widely used to obtain the reaction of the enzyme with surfaces, chemical modifiers, etc.) and even its “in vivo” behavior. This review will show some examples of chemical (mainly modifying the carboxylic groups using the carbodiimide route), physical (using polycationic polymers like polyethyleneimine) and genetic amination of the enzyme surface. Special emphasis will be put on cases where the amination is performed to improve subsequent protein modifications. Thus, amination has been used to increase the intensity of the enzyme/support multipoint covalent attachment, to improve the interaction with cation exchanger supports or polymers, or to promote the formation of crosslinkings (both intra-molecular and in the production of crosslinked enzyme aggregates). In other cases, amination has been used to directly modulate the enzyme properties (both in immobilized or free form). Amination of the enzyme surface may also pursue other goals not related to biocatalysis. For example, it has been used to improve the raising of antibodies against different compounds (both increasing the number of haptamers per enzyme and the immunogenicity of the composite) or the ability to penetrate cell membranes. Thus, amination may be a very powerful tool to improve the use of enzymes and proteins in many different areas and a great expansion of its usage may be expected in the near future.This work has been supported by grant CTQ2013-41507-R from Spanish MINECO, grant no. 1102-489-25428 from COLCIENCIAS and Universidad Industrial de Santander (VIE-UIS Research Program) and CNPq and FAPERGS (Brazil). A. Berenguer-Murcia thanks the Spanish Ministerio de Ciencia e Innovacion for a Ramon y Cajal fellowship (RyC-2009–03813)

Prevalence, associated factors and outcomes of pressure injuries in adult intensive care unit patients: the DecubICUs study

Funder: European Society of Intensive Care Medicine; doi: http://dx.doi.org/10.13039/501100013347Funder: Flemish Society for Critical Care NursesAbstract: Purpose: Intensive care unit (ICU) patients are particularly susceptible to developing pressure injuries. Epidemiologic data is however unavailable. We aimed to provide an international picture of the extent of pressure injuries and factors associated with ICU-acquired pressure injuries in adult ICU patients. Methods: International 1-day point-prevalence study; follow-up for outcome assessment until hospital discharge (maximum 12 weeks). Factors associated with ICU-acquired pressure injury and hospital mortality were assessed by generalised linear mixed-effects regression analysis. Results: Data from 13,254 patients in 1117 ICUs (90 countries) revealed 6747 pressure injuries; 3997 (59.2%) were ICU-acquired. Overall prevalence was 26.6% (95% confidence interval [CI] 25.9–27.3). ICU-acquired prevalence was 16.2% (95% CI 15.6–16.8). Sacrum (37%) and heels (19.5%) were most affected. Factors independently associated with ICU-acquired pressure injuries were older age, male sex, being underweight, emergency surgery, higher Simplified Acute Physiology Score II, Braden score 3 days, comorbidities (chronic obstructive pulmonary disease, immunodeficiency), organ support (renal replacement, mechanical ventilation on ICU admission), and being in a low or lower-middle income-economy. Gradually increasing associations with mortality were identified for increasing severity of pressure injury: stage I (odds ratio [OR] 1.5; 95% CI 1.2–1.8), stage II (OR 1.6; 95% CI 1.4–1.9), and stage III or worse (OR 2.8; 95% CI 2.3–3.3). Conclusion: Pressure injuries are common in adult ICU patients. ICU-acquired pressure injuries are associated with mainly intrinsic factors and mortality. Optimal care standards, increased awareness, appropriate resource allocation, and further research into optimal prevention are pivotal to tackle this important patient safety threat

Correction to: Prevalence, associated factors and outcomes of pressure injuries in adult intensive care unit patients: the DecubICUs study

The original version of this article unfortunately contained a mistake

Prevalence, associated factors and outcomes of pressure injuries in adult intensive care unit patients: the DecubICUs study

Funder: European Society of Intensive Care Medicine; doi: http://dx.doi.org/10.13039/501100013347Funder: Flemish Society for Critical Care NursesAbstract: Purpose: Intensive care unit (ICU) patients are particularly susceptible to developing pressure injuries. Epidemiologic data is however unavailable. We aimed to provide an international picture of the extent of pressure injuries and factors associated with ICU-acquired pressure injuries in adult ICU patients. Methods: International 1-day point-prevalence study; follow-up for outcome assessment until hospital discharge (maximum 12 weeks). Factors associated with ICU-acquired pressure injury and hospital mortality were assessed by generalised linear mixed-effects regression analysis. Results: Data from 13,254 patients in 1117 ICUs (90 countries) revealed 6747 pressure injuries; 3997 (59.2%) were ICU-acquired. Overall prevalence was 26.6% (95% confidence interval [CI] 25.9–27.3). ICU-acquired prevalence was 16.2% (95% CI 15.6–16.8). Sacrum (37%) and heels (19.5%) were most affected. Factors independently associated with ICU-acquired pressure injuries were older age, male sex, being underweight, emergency surgery, higher Simplified Acute Physiology Score II, Braden score 3 days, comorbidities (chronic obstructive pulmonary disease, immunodeficiency), organ support (renal replacement, mechanical ventilation on ICU admission), and being in a low or lower-middle income-economy. Gradually increasing associations with mortality were identified for increasing severity of pressure injury: stage I (odds ratio [OR] 1.5; 95% CI 1.2–1.8), stage II (OR 1.6; 95% CI 1.4–1.9), and stage III or worse (OR 2.8; 95% CI 2.3–3.3). Conclusion: Pressure injuries are common in adult ICU patients. ICU-acquired pressure injuries are associated with mainly intrinsic factors and mortality. Optimal care standards, increased awareness, appropriate resource allocation, and further research into optimal prevention are pivotal to tackle this important patient safety threat

erminación y crecimiento de plántulas de Phaseolus vulgaris L. en condiciones de salinidad*

Beans are sensitive to salinity. In Mexico in the autumn-winter cycle, bean production is performed under conditions of residual moisture. Under these conditions, salinity problems are increased and are reflected in the reduction in the percentage of germination, growth and underground and aerial performance. The levels of damage are different between varieties. In this research, conducted in Nayarit in 2012 in a greenhouse at a temperature of 28.1 °C, the physiological response to salinity induced with sodium chloride, three bean varieties of higher production in Nayarit in the germination stage and seedling was evaluated. The experimental design was completely randomized using three replicates per treatment. Pinto bean germination decreased 54.7% to 9 dS m-1 and beans Azufrado 30.3%. In seedlings, the stem length difference between the control (T0) and the highest treatment (T6) was 2.4, 4 and 3.2 cm for the Negro, Pinto and Azufrado respectively beans. The difference in root length between T0 and T6, was 13.1, 13.4 and 12.1 cm for the Negro, Pinto and Azufrado respectively beans. It as the electrical conductivity increased germination rate decreased. The Azufrado beans were the toughest and the most affected Pinto. The stem length, fresh weight and dry weight of seedling decreased and increased stem diameter. The length, fresh weight and dry root weight decreased gradually.El frijol es sensible a la salinidad. En México en el ciclo otoño-invierno, la producción del frijol se realiza en condiciones de humedad residual. En estas condiciones los problemas de salinidad se incrementan y se manifiesta en la reducción del porcentaje de germinación, el crecimiento aéreo y subterráneo y el rendimiento. Los grados de afectación son diferentes entre variedades. En ésta investigación, realizada en Nayarit en 2012 en invernadero a una temperatura de 28.1 °C, se evaluó la respuesta fisiológica a la salinidad, inducida con cloruro de sodio, de tres variedades de frijol de mayor producción en Nayarit en la etapa de germinación y plántula. El diseño experimental fue completamente al azar empleando tres repeticiones por tratamiento. La germinación del frijol Pinto se redujo 54.7% a 9 dS m-1 y el frijol Azufrado 30.3%. En plántula, la diferencia de longitud de tallo entre el testigo (T0) y el tratamiento más alto (T6) fue de 2.4, 4 y 3.2 cm para el frijol Negro, Pinto y Azufrado, respectivamente. La diferencia en longitud de raíz entre T0 y T6, fue de 13.1, 13.4 y 12.1 cm para el frijol Negro, Pinto y Azufrado, respectivamente. Conforme la conductividad eléctrica se incrementó la tasa de germinación disminuyó. El frijol Azufrado fue el más resistente y el Pinto el más afectado. La longitud de tallo, el peso fresco y peso seco de la plántula disminuyó y el diámetro de tallo incrementó. La longitud, peso fresco y peso seco de la raíz disminuyó gradualmente