Energy transfer in N-component nanosystems enhanced by pulse-driven vibronic many-body entanglement.

The processing of energy by transfer and redistribution, plays a key role in the evolution of dynamical systems. At the ultrasmall and ultrafast scale of nanosystems, quantum coherence could in principle also play a role and has been reported in many pulse-driven nanosystems (e.g. quantum dots and even the microscopic Light-Harvesting Complex II (LHC-II) aggregate). Typical theoretical analyses cannot easily be scaled to describe these general N-component nanosystems; they do not treat the pulse dynamically; and they approximate memory effects. Here our aim is to shed light on what new physics might arise beyond these approximations. We adopt a purposely minimal model such that the time-dependence of the pulse is included explicitly in the Hamiltonian. This simple model generates complex dynamics: specifically, pulses of intermediate duration generate highly entangled vibronic (i.e. electronic-vibrational) states that spread multiple excitons - and hence energy - maximally within the system. Subsequent pulses can then act on such entangled states to efficiently channel subsequent energy capture. The underlying pulse-generated vibronic entanglement increases in strength and robustness as N increases.

Epidemiology of sepsis in Colombian intensive care units.

INTRODUCTION: Currently, there is not enough data available concerning sepsis in developing countries, especially in Latin America. OBJECTIVE: We developed a study aimed at determining the frequency, clinical and epidemiological characteristics, and the consequences of sepsis in patients requiring admission to intensive care units in Colombia. MATERIALS AND METHODS: This was a secondary analysis of a prospective cohort study carried out over a six-month period, from September 1, 2007, to February 28, 2008, in ten medical/surgical intensive care units in four Colombian cities. Patients were considered eligible if they had a probable or confirmed diagnosis of infection according to medical records. We recorded demographic characteristics, first admission diagnosis and co-morbidities, clinical status, and sepsis, severe sepsis or septic shock. RESULTS: During the study period, 826 patients were admitted to the intensive care units. From these patients, 421 (51%) developed sepsis in the community, 361 (44%) in the ICU, and 44 (5%) during hospitalization in the general ward. Two hundred and fifty three patients (30.6%) had involvement of one organ system: 20% had respiratory involvement, followed by kidney and central nervous system involvement with 3.4% and 2.7%, respectively. CONCLUSIONS: In our cohort of septic patients, the prevalence of sepsis treated in ICU is similar to that reported in other studies, as well as the overall mortality.

Epidemiology of sepsis in Colombian intensive care units / Epidemiología de la sepsis en unidades de cuidado intensivo en Colombia

Introduction: Currently, there is not enough data available concerning sepsis in developing countries, especially in Latin America. Objective: We developed a study aimed at determining the frequency, clinical and epidemiological characteristics, and the consequences of sepsis in patients requiring admission to intensive care units in Colombia. Materials and methods: This was a secondary analysis of a prospective cohort study carried out over a six-month period, from September 1, 2007, to February 28, 2008, in ten medical/surgical intensive care units in four Colombian cities. Patients were considered eligible if they had a probable or confirmed diagnosis of infection according to medical records. We recorded demographic characteristics, first admission diagnosis and co-morbidities, clinical status, and sepsis, severe sepsis or septic shock. Results: During the study period, 826 patients were admitted to the intensive care units. From these patients, 421 (51%) developed sepsis in the community, 361 (44%) in the ICU, and 44 (5%) during hospitalization in the general ward. Two hundred and fifty three patients (30.6%) had involvement of one organ system: 20% had respiratory involvement, followed by kidney and central nervous system involvement with 3.4% and 2.7%, respectively. Conclusions: In our cohort of septic patients, the prevalence of sepsis treated in ICU is similar to that reported in other studies, as well as the overall mortality.

Introducción. Actualmente no se cuenta con muchos datos disponibles sobre la sepsis en los países en desarrollo y especialmente en América Latina. Objetivo. Este estudio tuvo como objetivo determinar la frecuencia, las características clínicas y epidemiológicas y las consecuencias de la sepsis en una población de pacientes que requirieron ingreso en algunas unidades colombianas de cuidados intensivos. Materiales y métodos. Este fue un análisis secundario de un estudio prospectivo realizado en un período de seis meses contados a partir del 1° de septiembre de 2007 hasta el 28 de febrero del 2008 en diez unidades médico-quirúrgicas de cuidados intensivos de cuatro ciudades de Colombia. Los pacientes se consideraron elegibles si tenían un diagnóstico probable o confirmado de infección según los registros médicos. Se registraron las características demográficas, los diagnósticos de primer ingreso y las enfermedades concomitantes, el estado clínico y la sepsis, sepsis grave o choque séptico. Resultados. Durante el período de estudio, 826 pacientes fueron ingresados en las unidades de cuidados intensivos seleccionadas para el estudio. De estos pacientes, 421 (51 %) desarrollaron sepsis en la comunidad, 361 (44 %) en la unidad de cuidados intensivos y 44 (5 %) durante la hospitalización en la sala general; 253 pacientes (30,6 %) presentaron afectación de un órgano del sistema: 20 % tuvo problemas respiratorios, seguido por problemas en los riñones y el sistema nervioso central con 3,4 % y 2,7 %, respectivamente. Conclusiones. En la muestra de pacientes sépticos, la prevalencia de la sepsis, así como de la mortalidad global, en los pacientes tratados en la unidad de cuidados intensivos fue similar a la reportada en otros estudios.

Lactato sérico en urgencias como factor pronóstico en pacientes con sepsis sin hipotensión / Serum lactate in the emergency department as a prognostic factor in patients with sepsis without hypotension

Fundamento y objetivo: La relación del lactato y la mortalidad en sepsis no ha sido explorada adecuadamente en el paciente normotenso. Nuestro objetivo fue determinar la utilidad del lactato como factor pronóstico de mortalidad a los 28 días en pacientes admitidos en el Servicio de Urgencias con diagnóstico clínico de sepsis y sin shock séptico. Pacientes y método: Análisis secundario del estudio La epidemiología de la sepsis en Colombia, una cohorte prospectiva de pacientes en 10 hospitales generales de 4 ciudades de Colombia. Se incluyeron en este análisis los pacientes sin hipotensión, con disponibilidad de lactato y admitidos con infecciones adquiridas en la comunidad confirmadas con los criterios de los Centers for Disease Control and Prevention. Se realizó una regresión logística controlando para la edad, el sexo, las comorbilidades y la puntuación de gravedad. Resultados: Se incluyeron 961 pacientes, con edad media (DE) de 57,2 (21,0) años, el 54,2% eran mujeres, la puntuación SOFA (Sequential Organ Failure Assessment) promedio fue de 3,0 (2,3) y el APACHE (Acute Physiologic and Chronic Health Evaluation) de 11,1 (6,4). Se observó un buen ajuste al modelo lineal entre el lactato y el riesgo de muerte, y al ajustar por los factores de confusión el lactato se asoció de manera significativa con la mortalidad (odds ratio 1,16, intervalo de confianza del 95% 1,02-1,33). Conclusión: El valor de lactato se asocia de forma independiente y significativa con la mortalidad a los 28 días entre los pacientes con infección que se presentan en el Departamento de Urgencias sin hipotensión. Además, la mortalidad se incrementa de manera lineal con los valores de lactato sérico a partir de cualquier valor detectable (AU)

Background and objective: The relationship between lactate and mortality in patients without hypotension has not been appropriately explored. Our aim was to determine the usefulness of serum lactate as a prognostic factor of 28-day mortality in patients admitted to the Emergency Department with clinical diagnosis of sepsis without septic shock. Patients and methods: We performed a secondary analysis of the study The epidemiology of sepsis in Colombia, a prospective cohort of patients from 10 general hospitals in 4 Colombian cities. We analyzed patients without hypotension with serum lactate available and admitted with community-acquired infections, which were confirmed according to the Centers for Disease Control and Prevention CDC criteria. A logistical regression was performed adjusting for age, sex, comorbidities and severity scores. Results: We included 961 patients aged 57.2 ± 21.0 years, 54.2% were females, mean SOFA score was 3.0 ± 2.3 and APACHE score was 11.1 ± 6.4. We observed a linear relationship between serum lactate and the odds of death, and after adjustment there was a significant and independent association between lactate and mortality (odds ratio 1,16, 95% confidence interval 1.02-1.33). Conclusion: Serum lactate is independently and significantly associated with 28-day mortality among patients with infection who present to the Emergency Department without hypotension. Besides, mortality increases in a linear way with serum lactate from any detectable value (AU)

Extreme alien light allows survival of terrestrial bacteria.

Photosynthetic organisms provide a crucial coupling between the Sun's energy and metabolic processes supporting life on Earth. Searches for extraterrestrial life focus on seeking planets with similar incident light intensities and environments. However the impact of abnormal photon arrival times has not been considered. Here we present the counterintuitive result that broad classes of extreme alien light could support terrestrial bacterial life whereas sources more similar to our Sun might not. Our detailed microscopic model uses state-of-the-art empirical inputs including Atomic Force Microscopy (AFM) images. It predicts a highly nonlinear survivability for the basic lifeform Rsp. Photometricum whereby toxic photon feeds get converted into a benign metabolic energy supply by an interplay between the membrane's spatial structure and temporal excitation processes. More generally, our work suggests a new handle for manipulating terrestrial photosynthesis using currently-available extreme value statistics photon sources.

Clinical course of sepsis, severe sepsis, and septic shock in a cohort of infected patients from ten Colombian hospitals.

BACKGROUND: Sepsis has several clinical stages, and mortality rates are different for each stage. Our goal was to establish the evolution and the determinants of the progression of clinical stages, from infection to septic shock, over the first week, as well as their relationship to 7-day and 28-day mortality. METHODS: This is a secondary analysis of a multicenter cohort of inpatients hospitalized in general wards or intensive care units (ICUs). The general estimating equations (GEE) model was used to estimate the risk of progression and the determinants of stages of infection over the first week. Cox regression with time-dependent covariates and fixed covariates was used to determine the factors related with 7-day and 28-day mortality, respectively. RESULTS: In 2681 patients we show that progression to severe sepsis and septic shock increases with intraabdominal and respiratory sources of infection [OR = 1,32; 95%IC = 1,20-1,46 and OR = 1.21, 95%CI = 1,11-1,33 respectively], as well as according to Acute Physiology and Chronic Health Evaluation II (APACHE II) [OR = 1,03; 95%CI = 1,02-1,03] and Sequential Organ Failure Assessment (SOFA) [OR = 1,16; 95%CI = 1,14-1,17] scores. The variables related with first-week mortality were progression to severe sepsis [HR = 2,13; 95%CI = 1,13-4,03] and septic shock [HR = 3,00; 95%CI = 1,50-5.98], respiratory source of infection [HR = 1,76; 95%IC = 1,12-2,77], APACHE II [HR = 1,07; 95% CI = 1,04-1,10] and SOFA [HR = 1,09; 95%IC = 1,04-1,15] scores. CONCLUSIONS: Intraabdominal and respiratory sources of infection, independently of SOFA and APACHE II scores, increase the risk of clinical progression to more severe stages of sepsis; and these factors, together with progression of the infection itself, are the main determinants of 7-day and 28-day mortality.

[Serum lactate in the emergency department as a prognostic factor in patients with sepsis without hypotension]. / Lactato sérico en urgencias como factor pronóstico en pacientes con sepsis sin hipotensión.

BACKGROUND AND OBJECTIVE: The relationship between lactate and mortality in patients without hypotension has not been appropriately explored. Our aim was to determine the usefulness of serum lactate as a prognostic factor of 28-day mortality in patients admitted to the Emergency Department with clinical diagnosis of sepsis without septic shock. PATIENTS AND METHODS: We performed a secondary analysis of the study The epidemiology of sepsis in Colombia, a prospective cohort of patients from 10 general hospitals in 4 Colombian cities. We analyzed patients without hypotension with serum lactate available and admitted with community-acquired infections, which were confirmed according to the Centers for Disease Control and Prevention CDC criteria. A logistical regression was performed adjusting for age, sex, comorbidities and severity scores. RESULTS: We included 961 patients aged 57.2 ± 21.0 years, 54.2% were females, mean SOFA score was 3.0 ± 2.3 and APACHE score was 11.1±6.4. We observed a linear relationship between serum lactate and the odds of death, and after adjustment there was a significant and independent association between lactate and mortality (odds ratio 1,16, 95% confidence interval 1.02-1.33). CONCLUSION: Serum lactate is independently and significantly associated with 28-day mortality among patients with infection who present to the Emergency Department without hypotension. Besides, mortality increases in a linear way with serum lactate from any detectable value.

The epidemiology of sepsis in Colombia: a prospective multicenter cohort study in ten university hospitals.

OBJECTIVE: Our aim was to determine the frequency and the clinical and epidemiologic characteristics of sepsis in a hospital-based population in Colombia. DESIGN: Prospective cohort. SETTING: Ten general hospitals in the four main cities of Colombia. PATIENTS: Consecutive patients admitted in emergency rooms, intensive care units, and general wards from September 1, 2007, to February 29, 2008, with confirmation of infection according to the Centers for Disease Control and Prevention definitions. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: The following information was recorded: demographic, clinical, and microbiologic characteristics; Acute Physiology and Chronic Health Evaluation II and Sequential Organ Failure Assessment scores; requirement for intensive care unit; length of stay; and 28-day all-cause mortality. During a period of 6 months, 2,681 patients were recruited: 69% and 31% with community-acquired and hospital-acquired infections, respectively. The mean age was 55 yrs (SD = 21), 51% were female, and the median length of stay was 10 days (interquartile range, 5-19). The mean Acute Physiology and Chronic Health Evaluation score was 11.5 (SD = 7) and the mean Sequential Organ Failure Assessment score was 3.8 (SD = 3). A total of 422 patients with community-acquired infections (16%) were admitted to the intensive care unit as a consequence of their infection and the median length of stay was 4.5 days in the intensive care unit. At admission, 2516 patients (94%) met at least one sepsis criterion and 1,658 (62%) met at least one criterion for severe sepsis. Overall, the 28-day mortality rates of patients with infection without sepsis, sepsis without organ dysfunction, severe sepsis without shock, and septic shock were 3%, 7.3%, 21.9%, and 45.6%, respectively. In community-acquired infections, the most frequent diagnosis was urinary tract infection in 28.6% followed by pneumonia in 22.8% and soft tissue infections in 21.8%. Within hospital-acquired infections, pneumonia was the most frequent diagnosis in 26.6% followed by urinary tract infection in 20.4% and soft tissue infections in 17.4%. CONCLUSIONS: In a general inpatient population of Colombia, the rates of severe sepsis and septic shock are higher than those reported in the literature. The observed mortality is higher than the predicted by the Acute Physiology and Chronic Health Evaluation II score.

Light-harvesting mechanism of bacteria exploits a critical interplay between the dynamics of transport and trapping.

Light-harvesting bacteria Rhodospirillum photometricum were recently found to adopt strikingly different architectures depending on illumination conditions. We present analytic and numerical calculations which explain this observation by quantifying a dynamical interplay between excitation transfer kinetics and reaction center cycling. High light-intensity membranes exploit dissipation as a photoprotective mechanism, thereby safeguarding a steady supply of chemical energy, while low light-intensity membranes efficiently process unused illumination intensity by channeling it to open reaction centers. More generally, our analysis elucidates and quantifies the trade-offs in natural network design for solar energy conversion.

Guía de práctica clínica para el diagnóstico y tratamiento de la sepsis en el servicio de urgencias de adultos / Clinical guidelines for diagnosis and treatment of sepsis in adults' emergency room

La respuesta que desarrolla un hospedero frente a una infección puede llevar a un espectro de manifestaciones que incluye desde la sepsis hasta laL disfunción orgánica múltiple y la muerte. Dada la complejidad del fenómeno fisiopatológico, las manifestaciones clínicas son muy variadas y, en ocasiones, tan sutiles que para detectarlas se requiere un alto índice de sospecha por parte del médico tratante. El juicio clínico se debe complementar con los exámenes de laboratorio pertinentes para lograr el diagnóstico oportuno, lo que permite iniciar las medidas de tratamiento adecuadas: la optimización hemodinámica temprana, la terapia antimicrobiana y las medidas de soporte.

Guía de práctica clínica para el diagnóstico y tratamiento de la sepsis en el servicio de urgencias de adultos / Clinical guidelines for diagnosis and treatment of sepsis in adult's emergency room

La respuesta que desarrolla un hospedero frente a una infección puede llevar a un espectro de manifestaciones que incluye desde la sepsis hasta la disfunción orgánica múltiple y la muerte. Dada la complejidad del fenómeno fisiopatológico, las manifestaciones clínicas son muy variadas y, en ocasiones, tan sutiles que para detectarlas se requiere un alto índice de sospecha por parte del médico tratante. El juicio clínico se debe complementar con los exámenes de laboratorio pertinentes para lograr el diagnóstico oportuno, lo que permite iniciar las medidas de tratamiento adecuadas: la optimización hemodinámica temprana, la terapia antimicrobiana y las medidas de soporte.

Host response against infection may produce a wide spectrum of clinical manifestations, from sepsis toorgan dysfunction and death. Since the underlying process is complex, clinical findings are varied and may be so subtle that a high level of diagnostic suspicion is required. Clinical judgment should becomplemented with appropriate laboratory tests so that the correct treatment, including haemodynamicoptimization, antimicrobial therapy and general supportive measures, can be started early.