The role of core and accessory type IV pilus genes in natural transformation and twitching motility in the bacterium Acinetobacter baylyi.

Here we present an examination of type IV pilus genes associated with competence and twitching in the bacterium Acinetobacter baylyi (strain ADP1, BD413). We used bioinformatics to identify potential competence and twitching genes and their operons. We measured the competence and twitching phenotypes of the bioinformatically-identified genes. These results demonstrate that competence and twitching in A. baylyi both rely upon a core of the same type IV pilus proteins. The core includes the inner membrane assembly platform (PilC), a periplasmic assemblage connecting the inner membrane assembly platform to the secretin (ComM), a secretin (ComQ) and its associated pilotin (PilF) that assists with secretin assembly and localization, both cytoplasmic pilus retraction ATPases (PilU, PilT), and pilins (ComP, ComB, PilX). Proteins not needed for both competence and twitching are instead found to specialize in either of the two traits. The pilins are varied in their specialization with some required for either competence (FimT) and others for twitching (ComE). The protein that transports DNA across the inner membrane (ComA) specializes in competence, while signal transduction proteins (PilG, PilS, and PilR) specialize in twitching. Taken together our results suggest that the function of accessory proteins should not be based on homology alone. In addition the results suggest that in A. baylyi the mechanisms of natural transformation and twitching are mediated by the same set of core Type IV pilus proteins with distinct specialized proteins required for each phenotype. Finally, since competence requires multiple pilins as well as both pilus retraction motors PilU and PilT, this suggests that A. baylyi employs a pilus in natural transformation.

Disparity Implications of Proposed 2015 Medicare Eligibility Criteria for Medication Therapy Management Services.

OBJECTIVES: Previous studies found that racial and ethnic minorities may be less likely than non-Hispanic Whites (Whites) to meet existing Medicare medication therapy management (MTM) eligibility criteria. To address these issues, the Centers for Medicare & Medicaid Services (CMS) proposed alternative Medicare MTM eligibility criteria for 2015. Due to opposition to other Part D reforms proposed simultaneously by various stakeholders, CMS rescinded all proposed reforms. This study was conducted to determine whether non-Hispanic Blacks (Blacks) and Hispanics have lower likelihood of meeting the proposed 2015 Medicare MTM eligibility criteria. METHODS: This retrospective observational analysis used Medical Expenditure Panel Survey data (2010-2011). The final study sample was comprised of 2,721 Whites (weighted to 37,185,896), 917 Blacks (weighted to 4,665,644), and 538 Hispanics (weighted to 3,532,882). Chi-square tests were used to examine racial and ethnic disparities in meeting proposed 2015 MTM eligibility criteria and each component of proposed 2015 MTM eligibility criteria. In multivariate analysis, a logistic regression model was used to control for population socio-demographic and health-related characteristics. KEY FINDINGS: Compared to Whites with a proportion of MTM eligibility of 58.82%, the eligible proportion was 57.09% (P=0.20) for Blacks, and 48.97% (P<0.0001) for Hispanics, respectively. According to multivariate logistic regression, odds ratios of meeting MTM eligibility for Blacks and Hispanics compared to Whites were 0.74 (95% Confidence Internal [CI] = 0.62-0.88) and 0.53 (95% CI=0.43-0.67), respectively. CONCLUSIONS: The proposed 2015 MTM eligibility criteria would not eliminate racial and ethnic disparities in MTM eligibility. Alternative MTM eligibility criteria should be devised.

Early diagnosis of intra-abdominal inflammation and sepsis by neutrophil CD64 expression in newborns.

BACKGROUND: Newborn infants with intra-abdominal inflammation/sepsis often present with nonspecific signs in the early stages of the disease, but can rapidly develop life-threatening complications. A reliable 'early' biomarker would be invaluable. OBJECTIVE: To evaluate the effectiveness of neutrophil CD64 as an 'early' biomarker of intra-abdominal inflammation/sepsis. METHODS: Blood was collected from newborns with suspected intra-abdominal pathology for neutrophil CD64 and C-reactive protein (CRP) determination at the onset of clinical presentation and 24 h later. They were classified into three groups: intra-abdominal inflammation/sepsis (group 1), extra-abdominal sepsis (group 2) and nonsepsis (group 3). Between-group comparisons were made by Kruskal-Wallis and χ(2) tests. Receiver-operating characteristic curves and diagnostic utilities for single and combination of tests were determined. RESULTS: 310 infants were recruited (102, 34 and 174 in groups 1, 2 and 3, respectively). CD64 (conventional cutoff = 6,010 antibody-PE molecules bound/cell) had substantially better sensitivity (0.81 vs. 0.56) and negative predictive value (0.90 vs. 0.79) for diagnosing intra-abdominal sepsis than CRP, at presentation. Pairing CD64 with routine abdominal radiograph (AXR) substantially increased the sensitivity and negative predictive value for group 1 to 0.99 and 0.99, respectively. By adjusting the CD64 cutoff to 12,500 units, a substantial improvement in specificity could be achieved (0.62 to 0.80) without significantly compromising sensitivity (0.99 to 0.97). CONCLUSIONS: CD64 is a sensitive and 'early' biomarker for diagnosing intra-abdominal inflammation/sepsis. Intra-abdominal catastrophes, including necrotizing enterocolitis, intestinal necrosis, perforation and peritonitis can confidently be excluded using CD64 and AXR early in the course of the disease.

A regulatory toolbox of MiniPromoters to drive selective expression in the brain.

The Pleiades Promoter Project integrates genomewide bioinformatics with large-scale knockin mouse production and histological examination of expression patterns to develop MiniPromoters and related tools designed to study and treat the brain by directed gene expression. Genes with brain expression patterns of interest are subjected to bioinformatic analysis to delineate candidate regulatory regions, which are then incorporated into a panel of compact human MiniPromoters to drive expression to brain regions and cell types of interest. Using single-copy, homologous-recombination "knockins" in embryonic stem cells, each MiniPromoter reporter is integrated immediately 5' of the Hprt locus in the mouse genome. MiniPromoter expression profiles are characterized in differentiation assays of the transgenic cells or in mouse brains following transgenic mouse production. Histological examination of adult brains, eyes, and spinal cords for reporter gene activity is coupled to costaining with cell-type-specific markers to define expression. The publicly available Pleiades MiniPromoter Project is a key resource to facilitate research on brain development and therapies.

Impact of a student response system on short- and long-term learning in a drug literature evaluation course.

OBJECTIVE: To evaluate the effectiveness of a student response system on short- and long-term learning in a required second-year pharmacy course. METHOD: Student volunteers enrolled in the course Drug Literature Evaluation were blinded and randomized to 1 of 2 groups. Group 1 attended a lecture in which the instructor used a student response system. Group 2 attended the same lecture by the same instructor an hour later, but no student response system was used. A 16-point unannounced quiz on the lecture material was administered to both groups at the end of class. Approximately 1 month later, both groups were given another unannounced quiz on the same material to test long-term student learning. RESULTS: One hundred seventy-nine (92.3%) students participated in both quizzes. Students who attended the class in which the student response system was used scored an average 1 point higher on quiz 1 than students who were assigned to the control group (10.7 vs. 9.7; p = 0.02). No significant difference was seen between the quiz 2 scores of the 2 groups (9.5 vs. 9.5; p = 0.99). CONCLUSIONS: The use of a student response system can positively impact students' short-term learning; however, that positive effect did not appear to last over time. Faculty members may want to consider the use of student response systems to enhance student learning in large lecture classes.

Attitudes toward neonatal intensive care treatment of preterm infants with a high risk of developing long-term disabilities.

OBJECTIVES: To assess (1) the differences in attitudes toward disabilities of 3 groups of subjects involved in neonatal care decision-making: health care workers, mothers of term infants, and parents of preterm infants, and (2) the impact of subject characteristics on these attitudes including parental education level, religion, and severity of disability. METHODS: Five hundred seventy-eight subjects were interviewed, of whom 135 were health care workers, 155 were mothers of term infants, and 288 were parents of preterm infants. We assessed between-group differences of the (1) health state ranking permutations, (2) proportion of subjects willing to save the infant at all costs, (3) pivotal risks of each group to the 5 health states comprising varying combinations of mental, physical, and social disabilities, and (4) impact of personal characteristics on decision-making. RESULTS: Most health care workers ranked the most severe disability health state as worse than death, whereas most parents of preterm infants ranked death as the worst outcome. Significantly more parents of preterm infants chose to save the infant at all costs, compared with mothers of term infants and health care workers, and the pivotal risks of the parents of preterm infants group were highest for all health states. Religious worship was associated with increased probability of saving at all costs and pivotal risks. Increased severity of neonatal complications was associated with decreased probability of saving at all costs and pivotal risks in parents of preterm infants. CONCLUSIONS: Our findings suggest that parents of preterm infants as a group were most likely to save the infant at all costs and prepared to tolerate more severe disability health states. However, personal characteristics, in particular religious belief and severity of neonatal complications, have overriding influence on these attitudes. We suggest inclusion of experienced parents of preterm infants for more effective counseling of parents in making life-and-death decisions.

High-dose oral erythromycin decreased the incidence of parenteral nutrition-associated cholestasis in preterm infants.

BACKGROUND & AIMS: Feeding intolerance because of functional gastrointestinal dysmotility and parenteral nutrition-associated cholestasis (PNAC) are common problems in preterm, very-low-birth-weight (VLBW) infants. This double-blind, randomized, placebo-controlled study aimed to assess the effectiveness of "high-dose" oral erythromycin as a prokinetic agent in decreasing the incidence of PNAC. Two secondary end points, including the time to achieve full enteral feeding and the duration of parenteral nutrition, were also evaluated. METHODS: Infants consecutively admitted to the neonatal unit were randomized to receive erythromycin (12.5 mg/kg/dose every 6 hours for 14 days) or an equivalent volume of normal saline (placebo) if they attained less than half the total daily fluid intake (<75 mL/kg/day) as milk feeds on day 14 of life. RESULTS: Of 182 VLBW infants enrolled, 91 received erythromycin. The incidence of PNAC was significantly lower in erythromycin-treated infants (18/91) compared with placebo infants (37/91; P = .003). Treated infants achieved full enteral nutrition significantly earlier (mean, 10.1; SE, 1.7 days; P < .001), and the duration of parenteral nutrition was also significantly decreased by 10 days (P < .001). Importantly, fewer infants receiving erythromycin had 2 or more episodes of septicemia (n = 4) compared with placebo patients (n = 13, P = .03). No serious adverse effect was associated with erythromycin treatment. CONCLUSIONS: High-dose oral erythromycin can be considered as a rescue measure for VLBW infants who fail to establish adequate enteral nutrition and in whom anatomically obstructive pathologies of the gastrointestinal tract have been excluded.