Biological active matter aggregates: Inspiration for smart colloidal materials.

Aggregations of social organisms exhibit a remarkable range of properties and functionalities. Multiple examples, such as fire ants or slime mold, show how a population of individuals is able to overcome an existential threat by gathering into a solid-like aggregate with emergent functionality. Surprisingly, these aggregates are driven by simple rules, and their mechanisms show great parallelism among species. At the same time, great effort has been made by the scientific community to develop active colloidal materials, such as microbubbles or Janus particles, which exhibit similar behaviors. However, a direct connection between these two realms is still not evident, and it would greatly benefit future studies. In this review, we first discuss the current understanding of living aggregates, point out the mechanisms in their formation and explore the vast range of emergent properties. Second, we review the current knowledge in aggregated colloidal systems, the methods used to achieve the aggregations and their potential functionalities. Based on this knowledge, we finally identify a set of over-arching principles commonly found in biological aggregations, and further suggest potential future directions for the creation of bio-inspired colloid aggregations.

A rapid assessment of barriers and facilitators to safety culture in an intensive care unit.

The Hospital Survey on Patient Safety was used to identify opportunities for safety culture improvement in a 30-bed intensive care unit. Based on the survey results, a core team decided to focus on three safety domains: reporting errors, approachability of authority figures and handovers. The project team subsequently interviewed 39 intensive care unit staff members, gathering information on these three domains that will inform future safety efforts. Numerous barriers and facilitators to improvement were described. This mixed-methods approach could be applied in other hospitals seeking to quickly yet thoroughly understand how their safety culture can be improved. Developing local strategies to reduce these barriers may promote a safer patient experience at our hospital.

N-terminal pro B type natriuretic peptide, but not the new putative cardiac hormone relaxin, predicts prognosis in patients with chronic heart failure.

OBJECTIVE: To determine whether the plasma concentration of the putative new cardiac hormone relaxin is predictive of clinical outcome in patients with chronic heart failure (CHF). DESIGN: Plasma relaxin and N-terminal pro B type natriuretic peptide (NT pro BNP) concentrations were measured in 87 patients admitted in an emergency with CHF caused by left ventricular systolic dysfunction. These were related to death and death or readmission with CHF over the following year. SETTING: Western Infirmary, Glasgow, UK. MAIN OUTCOME MEASURES: Plasma concentrations of relaxin and NT pro BNP; time to death or hospitalisation caused by heart failure. RESULTS: Plasma concentrations of both relaxin and NT pro BNP were greatly increased. Of the 43 patients with NT pro BNP above the group median concentration, 23 (53%) died and 30 (70%) died or were hospitalised with CHF. Among the 44 with concentrations below the median, these numbers were 5 (11%) and 12 (27%), respectively (p < 0.0001 and p < 0.0001, respectively). Plasma NT pro BNP concentration remained an independent predictor of an adverse clinical outcome in a multivariate analysis. Of the 42 patients with a relaxin concentration above the median, 13 (31%) died and 20 (48%) died or were hospitalised. Below the median, these numbers were 15 of 45 (33%) and 22 of 45 (49%) (p = 0.76 and p = 0.84, respectively). CONCLUSIONS: NT pro BNP is a powerful and independent predictor of outcome in CHF, whereas relaxin, also secreted by the heart in increased amounts in CHF, is not.

An economic analysis of specialist heart failure nurse management in the UK; can we afford not to implement it?

AIMS: Hospital activity represents the major component of health care expenditure related to heart failure. This study evaluated the economic impact of applying specialist nurse management programmes that limit heart failure-related hospital readmissions within a whole population. METHODS: Using a reliable and validated estimate of the current level and cost of heart failure-related hospital activity in the U.K., we determined the thresholds at which the actual cost of establishing and applying a national service based on three different models of specialist nurse management would be equal to the 'cost' of bed utilization associated with preventable hospital readmissions in the year 2000. The three models of care examined were home-based, clinic-based or a combination of home plus clinic-based, post-discharge follow-up. The potential impact of this service was based on a U.K.-wide caseload of 122,000 patients discharged to home with a discharge diagnosis of congestive heart failure in that year. RESULTS: Based on heart failure-specific patterns of hospital activity, we estimate that 47,000 of these 122,000 patients would normally accumulate a total of 594000 days of associated hospital stay from 49,000 readmissions (for any reason) within 1 year of hospital discharge. The cost of these admissions to the National Health Service was calculated at 166.2 million pounds sterling. Taking into account other costs associated with such hospital activity (e.g. general practice and hospital outpatient visits) each 10% reduction in recurrent bed utilization would be associated with 18.0 million ponds sterling in cost savings. Alternatively, the cost of applying a U.K.-wide programme of home-, clinic- or home plus clinic-based follow-up was calculated to be 69.4 pounds sterling, 73.1 pounds sterling and 72.5 million pounds sterling per annum, respectively. The relative thresholds at which generated 'cost-savings' would equal the cost of applying these programmes of care would therefore be a 38.5%, 40.6% and 40.3% reduction in recurrent bed utilization, respectively. If, as expected, a home-based programme of specialist nurse management reduced recurrent bed utilization by 50% or more, annual savings equivalent to 169,000 pounds sterling per 1000 patients treated would be generated. CONCLUSIONS: This is the first study to examine the economic consequences of applying a specialist nurse-mediated, post-discharge management service for heart failure within a whole population. Our findings suggest that such a service will not only improve quality of life and reduce readmissions in patients with congestive heart failure, but also reduce costs and improve the efficiency of the health care system in doing so.

Randomised controlled trial of specialist nurse intervention in heart failure.

OBJECTIVES: To determine whether specialist nurse intervention improves outcome in patients with chronic heart failure. DESIGN: Randomised controlled trial. SETTING: Acute medical admissions unit in a teaching hospital. PARTICIPANTS: 165 patients admitted with heart failure due to left ventricular systolic dysfunction. The intervention started before discharge and continued thereafter with home visits for up to 1 year. MAIN OUTCOME MEASURES: Time to first event analysis of death from all causes or readmission to hospital with worsening heart failure. RESULTS: 31 patients (37%) in the intervention group died or were readmitted with heart failure compared with 45 (53%) in the usual care group (hazard ratio=0.61, 95% confidence interval 0.33 to 0.96). Compared with usual care, patients in the intervention group had fewer readmissions for any reason (86 v 114, P=0.018), fewer admissions for heart failure (19 v 45, P<0.001) and spent fewer days in hospital for heart failure (mean 3.43 v 7.46 days, P=0.0051). CONCLUSIONS: Specially trained nurses can improve the outcome of patients admitted to hospital with heart failure.

Poles apart, but are they the same? A comparative study of Australian and Scottish patients with chronic heart failure.

This paper reports on an international comparison of the characteristics, treatment and health outcomes of chronic heart failure (CHF) patients discharged from acute hospital care in Australia and Scotland. The baseline characteristics and treatment of 200 CHF patients recruited to a randomised study of a non-pharmacological intervention in Australia and 157 CHF patients concurrently recruited to a similar study in Scotland were compared. Subsequent health outcomes (including survival and readmission) within 3 months of discharge in those patients who received usual post-discharge care in Australia (n=100) and Scotland (n=75) were also compared. Individuals in both countries were predominantly old and frail with significant comorbidity likely to complicate treatment. Similar proportions of Australian and Scottish patients were prescribed either a 'high' (20 vs. 18%) or medium (64 vs. 66%) dose of an angiotensin-converting enzyme inhibitor. Proportionately more Australian patients were prescribed a long-acting nitrate, digoxin and/or a beta-blocker. At 3 months post-discharge, 57 of the 100 (57%: 95% CI 47--67%) Australian and 37 of the 75 (49%: 95% CI 38--61%) Scottish patients assigned to 'usual care' remained event-free (NS). Similarly, 15 vs. 12% required > or =2 unplanned readmission (NS) and 16 vs. 19% of Australian and Scottish patients, respectively, died (NS). Australian and Scottish patients accumulated a median of 0.6 vs. 0.9 days, respectively, of hospitalisation/patient/month (NS). On multivariate analysis (including country of origin), unplanned readmission or death was independently correlated with severe renal impairment (adjusted odds ratio 4.4, P<0.05), a previous hospitalisation for CHF (2.3, P<0.05), longer index hospitalisation (2.7 for >10 days, P<0.05) and greater comorbidity (1.3 for each incremental unit of the Charlson Index, P=0.05). Health outcomes among predominantly old and frail CHF patients appear to be independent of the health-care system in which the patient is managed and more likely to be dependent on the syndrome itself.

Assessing and managing chronic heart failure.

Patients with chronic heart failure have a reduced quality of life. Symptoms can be managed, but there is no cure. Heart failure nurses can offer advice, education and support to patients. This article reviews the common causes of heart failure and the nursing interventions that can help manage the symptoms.

Evaluation of phase variation of nontypeable Haemophilus influenzae lipooligosaccharide during nasopharyngeal colonization and development of otitis media in the chinchilla model.

Nontypeable Haemophilus influenzae (NTHI) has four loci, lic-1 to lic-3 and lgtC, that generate phase-variable lipooligosaccharide (LOS) structures. lic-1, which is required for the expression of phosphorylcholine (ChoP), is the best characterized and is associated with an enhanced ability of H. influenzae to persist within the nasopharynges of infant rats. Recent data indicate that LOS impacts various aspects of NTHI virulence in the chinchilla model of nasopharyngeal colonization and otitis media (OM). In this study the effects of ChoP expression and the sequences of lic-1 to lic-3 and lgtC of NTHI strain 2019 were evaluated in the chinchilla OM model. Nasopharyngeal colonization data showed that a switch from the ChoP(-) to the ChoP(+) phenotype was observed as early as day 3 after intranasal inoculation. Chinchillas colonized by strains with the ChoP(+) phenotype demonstrated a significantly higher level of NTHI 2019 per milliliter of nasal lavage fluid than chinchillas colonized with predominantly the ChoP(-) variant (P < 0.05). The concentration of cells with the ChoP(+) phenotype in the middle ear was 3 log units higher than that of cells with the ChoP(-) variant (P < 0.01). There was a statistically significant association between ChoP(+) expression in the nasal lavage and the development of OM with culture-positive middle ear fluids in this model. These data suggest that expression of the ChoP(+) phenotype promotes enhanced nasopharyngeal colonization and development of OM.

Evaluation of the virulence of a Streptococcus pneumoniae neuraminidase-deficient mutant in nasopharyngeal colonization and development of otitis media in the chinchilla model.

Considerable evidence has implicated Streptococcus pneumoniae neuraminidase in the pathogenesis of otitis media (OM); however, its exact role has not been conclusively established. Recently, an S. pneumoniae neuraminidase-deficient mutant, DeltaNA1, has been constructed by insertion-duplication mutagenesis of the nanA gene of S. pneumoniae strain D39. The relative ability of DeltaNA1 and the D39 parent strain to colonize the nasopharynx and to induce OM subsequent to intranasal inoculation and to survive in the middle ear cleft after direct challenge of the middle ear were evaluated in the chinchilla model. Nasopharyngeal colonization data indicate a significant difference in the ability of the DeltaNA1 mutant to colonize as well as to persist in the nasopharynx. The neuraminidase-deficient mutant was eliminated from the nasopharynx 2 weeks earlier than the D39 parent strain. Both the parent and the mutant exhibited similar virulence levels and kinetics during the first week after direct inoculation of the middle ear. The DeltaNA1 neuraminidase-deficient mutant, however, was then completely eliminated from the middle ear by day 10 postchallenge, 11 days before the D39 parent strain. Data from this study indicate that products of the nanA gene have an impact on the ability of S. pneumoniae to colonize and persist in the nasopharynx as well as the middle ear.

Titration of vasodilator therapy in chronic heart failure according to plasma brain natriuretic peptide concentration: randomized comparison of the hemodynamic and neuroendocrine effects of tailored versus empirical therapy.

BACKGROUND: Most patients with chronic heart failure (CHF) receive the same dose of angiotensin-converting enzyme (ACE) inhibitors because there is currently no measure of treatment efficacy. We sought to determine whether titration of vasodilator therapy according to plasma brain natriuretic peptide (BNP) concentration may be of value in the individual optimization of vasodilator therapy in CHF. METHODS AND RESULTS: Twenty patients with mild to moderate CHF receiving stable conventional therapy including an ACE inhibitor were randomly assigned to titration of ACE inhibitor dosage according to serial measurement of plasma BNP concentration (BNP group) or optimal empirical ACE inhibitor therapy (clinical group) for 8 weeks. Only the BNP-driven approach was associated with significant reductions in plasma BNP concentration throughout the duration of the study and a significantly greater suppression when compared with empiric therapy after 4 weeks [-42.1% (-58.2, -19.7) vs -12.0% (-31.8, 13.8), P =.03]. Both treatment strategies were well tolerated and associated with favorable neurohormonal and hemodynamic effects; however, in comparison between groups, mean heart rate fell (P =.02) and plasma renin activity rose (P =.03) in the BNP group when compared with the clinical group. CONCLUSIONS: Plasma BNP concentration may be chronically reduced by tailored vasodilator therapy in CHF. Furthermore, titration of vasodilator therapy according to plasma BNP was associated with more profound inhibition of the renin-angiotensin-aldosterone system and significant fall in heart rate when compared with empiric therapy.

'Uncharted waters'--consolidation of two academic psychiatric services: a case study.

Surviving during times of mergers and acquisitions is difficult but possible. Following is a case study of how one service managed not only to survive, but to thrive, during consolidation.

Localization of FCGR1 encoding Fcgamma receptor class I in primates: molecular evidence for two pericentric inversions during the evolution of human chromosome 1.

The human high-affinity receptor for immunoglobulin G, FcgammaRI (FCGR1), is encoded by a family of three genes that share over 95% sequence homology. Curiously, the three genes in this recently duplicated gene family flank the centromere of human chromosome 1, with FCGR1B located at 1p12 and both FCGR1A and FCGR1C located at 1q21. We have previously speculated that a pericentric inversion could account for the separation of the genes in the FCGR1 family and explain their current chromosomal location. Here we present evidence, obtained through fluorescence in situ hybridization analysis, that in the rhesus monkey (Macaca mulatta) and baboon (Papio papio) FCGR1 is located adjacent to the centromere on the chromosomal arm with greatest homology to human 1p, whereas in the chimpanzee (Pan troglodytes) it is located adjacent to the centromere on the chromosomal arm with greatest homology to human 1q. The separation of the FCGR1 gene family in humans suggests that the location of a second pericentric inversion, known to distinguish the human from the chimpanzee chromosome 1, is within the FCGR1 gene family. This finding refines the assignment of homology between the human and chimpanzee chromosomes 1.

Early enteral nutrition support in patients undergoing liver transplantation.

BACKGROUND: The purpose of this study was to determine the effects of early postoperative tube feeding on outcomes of liver transplant recipients. METHODS: Fifty transplant patients were randomized prospectively to receive enteral formula via nasointestinal feeding tubes (tube-feeding [TF] group) or maintenance i.v. fluid until oral diets were initiated (control group). Thirty-one patients completed the study. Resting energy expenditure, nitrogen balance, and grip strength were measured on days 2, 4, 7, and 12 after liver transplantation. Calorie and protein intakes were calculated for 12 days posttransplant. RESULTS: Tube feeding was tolerated in the TF group (n = 14). The TF patients had greater cumulative 12-day nutrient intakes (22,464 +/- 3554 kcal, 927 +/- 122 g protein) than did the control patients (15,474 +/- 5265 kcal, 637 +/- 248 g protein) (p < .002). Nitrogen balance was better in the TF group on posttransplant day 4 than in the control group (p < .03). There was a rise in the overall mean resting energy expenditure in the first two posttransplant weeks from 1487 +/- 338 to 1990 +/- 367 kcal (p = .0002). Viral infections occurred in 17.7% of control patients compared with 0% of TF patients (p = .05). Although other infections tended to occur more frequently in the control group vs the TF group (bacterial, 29.4% vs 14.3%; overall infections, 47.1% vs 21.4%), these differences were not statistically significant. Early posttransplant tube feeding did not influence hospitalization costs, hours on the ventilator, lengths of stay in the intensive care unit and hospital, rehospitalizations, or rejection during the first 21 posttransplant days. CONCLUSIONS: Early posttransplant tube feeding was tolerated and promoted improvements in some outcomes and should be considered for all liver transplant patients.

Platelet MAO activity and personality variations in normals.

The authors examined platelet MAO activity and several personality variables in 58 non-clinic-referred healthy adult males. The psychological tests administered consisted of the Minnesota Multiphasic Personality Inventory, the Personality Research Form-E, and the Zuckerman Sensation Seeking Scale. The findings replicated previous findings in the literature.

A nutrition screening and assessment system for use with the elderly in extended care.

One area of particular interest to health care professionals that is undergoing considerable investigation is the nutritional status of the elderly. This article describes the development, implementation, and evaluation of a procedure used to nutritionally screen and assess geriatric patients in extended care at the Veterans Administration Medical Center in Houston. As we developed the system, we considered the special needs and characteristics of geriatric individuals and incorporated them into two forms. Designs were selected to make our method comprehensive, concise, and, ideally, time-efficient. The evaluation of the system included a time utilization study. This study was conducted to evaluate the efficiency of the new system compared with the efficiency of methods used hospital-wide in the past. Results suggest that the new system for reassessing the patient's nutritional status and reevaluating the nutrition care was three times more efficient.

The reliability of the routine chest roentgenogram for determination of heart size based on specific ventricular chamber evaluation at postmortem.

Routine posteroanterior and lateral chest radiographs in 268 patients were analyzed to determine heart size--normal, cardiomegaly, or specific chamber enlargement--using specified radiographic criteria for enlargement. The accuracy of this determination was compared with a specific ventricular mass derived from a postmortem cardiac chamber partition technique. The data indicate that in the majority of cases (greater than 70%) a normal-sized heart or cardiomegaly can be correctly determined from the chest x-ray either by the subjective criteria of chamber enlargement or by measurement of the transverse diameter. The use of the chest x-ray, however, for evaluation of specific ventricular chamber enlargement is a less accurate determination, and results are compromised.

Descriptive characteristics of the electrocardiogram from autopsied men free of cardiopulmonary disease--a basis for evaluating criteria for ventricular hypertrophy.

Most measurements establishing standard values for the normal electrocardiogram have been derived from a healthy population, whereas many electrocardiographic interpretations are necessary in hospitalized or seriously ill patients. Therefore, the characteristics of the electrocardiogram were described from 48 autopsied men known to be free of cardiopulmonary disease by clinical assessment and by a special cardiac examination using postmortem coronary angiography and a chamber partition technique. Highest values, mean and standard deviation, and the upper 97.5 percentile or lower 2.5 percentile when appropriate were noted for QRS voltage, QRS axis and duration, and intrinsicoid deflection in V5 or V6. Any ST-segment and T-wave changes were noted as well as left and right atrial abnormalities. Twenty-eight electrocardiographic criteria recommended to detect left ventricular hypertrophy and 10 recommended to detect right ventricular hypertrophy were evaluated for percentage of false-positive results and the 97.5 percentile value for each criterion was developed from the present data base. The data in this study can be used as a standard for comparing electrocardiographic variation in middle-aged men with specific relevance for electrocardiographic criteria of ventricular hypertrophy.