Processive stepping of myosin Va (myoV) has been tracked by monitoring either the tail position (center of mass) or the position of one or both heads. Here, we combine these two approaches by ...attaching a quantum dot to one of the motor domains and a bead to the tail. Using laser trapping and total internal reflection microscopy, the position of one head and the tail are observed simultaneously as myoV moves processively on an actin filament bundle against the resistive load of the laser trap. The head moves one step (73 ± 10 nm) for every two steps of the tail (35 ± 9 nm). One tail step occurs concurrently with quantum dot-labeled head movement, whereas the other occurs with movement of the unlabeled head, consistent with a hand-over-hand model. Load increases the probability of the motor taking a back step. The back step is triggered by the motor taking a shorter forward step (head step, 68 ± 11 nm; tail step, 32 ± 10 nm), likely one actin monomer short of its preferred binding site. During a back step, the motor reverses its hand-over-hand motion, with the leading head detaching and reattaching to one of multiple actin sites behind the trailing head. After a back step, the motor can correct its mistake and step processively forward at resistive loads <0.7 piconewton or stall or detach at higher loads. Back stepping may provide a mechanism to ensure efficient cargo delivery even when myoV encounters obstacles within the actin cytoskeletal meshwork or when other motors are attached to the same cargo.
The Critical Illness Stress-Induced Immune Suppression prevention trial was a randomized, masked trial of zinc, selenium, glutamine, and metoclopramide compared with whey protein in delaying ...nosocomial infection in PICU patients. One fourth of study subjects were diagnosed with nosocomial lower respiratory infection, which contributed to subjects receiving antibiotics 74% of all patient days in the PICU. We analyzed diagnostic and treatment variability among the participating institutions and compared outcomes between nosocomial lower respiratory infection subjects (n = 74) and intubated subjects without nosocomial infection (n = 1 55).
Post hoc analysis.
Eight hospitals in the Collaborative Pediatric Critical Care Research Network.
Critical Illness Stress-Induced Immune Suppression study subjects.
None.
Variability across institutions existed in the frequency and manner by which respiratory secretion cultures were obtained, processed, and results reported. Most results were reported semiquantitatively, and both Gram stains and antibiotic sensitivities were frequently omitted. The nosocomial lower respiratory infection diagnosis was associated with increased PICU lengths of stay compared with those who were intubated without nosocomial infection (24 ± 19 vs 9 ± 6 d; p < 0.001) and antibiotic use (38 ± 29 vs 15 ± 20 antibiotics days; p < 0.001). Despite antibiotic treatment, the same bacteria persisted in 45% of follow-up cultures.
The Critical Illness Stress-Induced Immune Suppression data demonstrate that the nosocomial lower respiratory infection diagnosis is associated with longer lengths of stay and increased antibiotic use, but there is considerable diagnostic and treatment variability across institutions. More rigorous standards for when and how respiratory cultures are obtained, processed, and reported are necessary. Bacterial persistence also complicates the interpretation of follow-up cultures.
Docker has become a very popular container-based virtualization platform for software distribution that has revolutionized the way in which scientific software and software dependencies (software ...stacks) can be packaged, distributed, and deployed. Docker makes the complex and time-consuming installation procedures needed for scientific software a one-time process. Because it enables platform-independent installation, versioning of software environments, and easy redeployment and reproducibility, Docker is an ideal candidate for the deployment of identical software stacks on different compute environments such as XSEDE and Amazon AWS. CyVerse's Discovery Environment also uses Docker for integrating its powerful, community-recommended software tools into CyVerse's production environment for public use. This paper will help users bring their tools into CyVerse Discovery Environment (DE) which will not only allows users to integrate their tools with relative ease compared to the earlier method of tool deployment in DE but will also help users to share their apps with collaborators and release them for public use.
Behavioral weight loss interventions achieve short-term success, but re-gain is common.
To compare 2 weight loss maintenance interventions with a self-directed control group.
Two-phase trial in which ...1032 overweight or obese adults (38% African American, 63% women) with hypertension, dyslipidemia, or both who had lost at least 4 kg during a 6-month weight loss program (phase 1) were randomized to a weight-loss maintenance intervention (phase 2). Enrollment at 4 academic centers occurred August 2003-July 2004 and randomization, February-December 2004. Data collection was completed in June 2007.
After the phase 1 weight-loss program, participants were randomized to one of the following groups for 30 months: monthly personal contact, unlimited access to an interactive technology-based intervention, or self-directed control. Main Outcome Changes in weight from randomization.
Mean entry weight was 96.7 kg. During the initial 6-month program, mean weight loss was 8.5 kg. After randomization, weight regain occurred. Participants in the personal-contact group regained less weight (4.0 kg) than those in the self-directed group (5.5 kg; mean difference at 30 months, -1.5 kg; 95% confidence interval CI, -2.4 to -0.6 kg; P = .001). At 30 months, weight regain did not differ between the interactive technology-based (5.2 kg) and self-directed groups (5.5 kg; mean difference -0.3 kg; 95% CI, -1.2 to 0.6 kg; P = .51); however, weight regain was lower in the interactive technology-based than in the self-directed group at 18 months (mean difference, -1.1 kg; 95% CI, -1.9 to -0.4 kg; P = .003) and at 24 months (mean difference, -0.9 kg; 95% CI, -1.7 to -0.02 kg; P = .04). At 30 months, the difference between the personal-contact and interactive technology-based group was -1.2 kg (95% CI -2.1 to -0.3; P = .008). Effects did not differ significantly by sex, race, age, and body mass index subgroups. Overall, 71% of study participants remained below entry weight.
The majority of individuals who successfully completed an initial behavioral weight loss program maintained a weight below their initial level. Monthly brief personal contact provided modest benefit in sustaining weight loss, whereas an interactive technology-based intervention provided early but transient benefit.
clinicaltrials.gov Identifier: NCT00054925.
Underserved and minority populations suffer from a disproportionately high prevalence of obesity and related comorbidities. Effective obesity treatment programs delivered in primary care that produce ...significant weight loss are currently lacking. The purpose of this trial is to test the effectiveness of a pragmatic, high intensity lifestyle-based obesity treatment program delivered within primary care among an underserved population. We hypothesize that, relative to patients who receive usual care, patients who receive a high-intensity, health literacy- and culturally-appropriate lifestyle intervention will have greater percent reductions in body weight over 24 months. Eighteen clinics (N = 803 patients) serving low income populations with a high proportion of African Americans in Louisiana were randomized to the intervention or usual car. Patients in the intervention participate in a high-intensity lifestyle program delivered by health coaches employed by an academic health center and embedded in the primary care clinics. The program consists of weekly (16 in-person/6 telephone) sessions in the first six months, followed by sessions held at least monthly for the remaining 18 months. Primary care practitioners in usual care receive information on weight management and the current Centers for Medicare and Medicaid Services reimbursement for obesity treatment. The primary outcome is percent weight loss at 24 months. Secondary outcomes include absolute 24-month changes in body weight, waist circumference, blood pressure, fasting glucose and lipids, health-related quality of life, and weight-related quality of life. The results will provide evidence on the effectiveness of implementing high-intensity lifestyle and obesity counseling in primary care settings among underserved populations.
Trial Registration: ClinicalTrials.gov Identifier NCT02561221
Occupational exposure to agrochemicals, some of which are known or suspected carcinogens, is a major health hazard for subsistence agricultural workers and their families. These impacts are more ...prevalent in low-and-middle income countries (LMIC) due to weak regulations, lack of awareness of the risks of contamination, predominant use of handheld backpack style spraying equipment, general lack of personal protective equipment (PPE), and low literacy about proper agrochemical application techniques. Reducing exposure to agrochemicals was identified as a paramount concern by rural Hondurans working with a community-engaged research initiative. Fluorescent tracer dyes have been described as a means of visualizing and quantifying dermal exposure to agricultural chemicals, and exposure models adapted for LMIC have been developed previously. Tracer dyes have also been used in educational simulations to promote pesticide safety. However, studies evaluating the effectiveness of these educational dye interventions in reducing future exposure have been lacking.
To evaluate whether observing one's own chemical contamination after applying agrochemicals changed the amount of occupational dermal exposure during a subsequent chemical application.
We employed a multi-modal community intervention in a rural village in Honduras that incorporated chemical safety education and use of a fluorescent tracer dye during pesticide application on two consecutive occasions, and compared dermal exposure between the intervention group (previous dye experience and safety education, n = 6) and the control group (safety education only, n = 7).
Mean total visual score (TVS) of the tracer dye, which accounts for both extent and intensity of whole-body contamination, was lower among those who had previously experienced the dye intervention (mean TVS = 41.3) than among participants who were dye-naïve (mean TVS = 78.4), with a difference between means of −37.10 (95% CI -66.26, −7.95, p = 0.02). Stratifying by body part, contamination was significantly lower for the anterior left lower extremity and bilateral feet for the dye-experienced group vs. dye-naïve, with most other segments showing a trend toward decreased contamination as well.
Participants who had previously experienced the dye intervention were significantly less contaminated than the dye-naïve control group during a subsequent spraying event. The findings of this small pilot study suggest that a multi-modal, community-based approach that utilizes fluorescence-augmented contamination for individualized learning (FACIL) may be effective in reducing dermal exposure to carcinogenic agrochemicals among subsistence farmers in Honduras and other LMIC.
•Subsistence farmers in Honduras are vulnerable to adverse effects of agrochemicals.•Fluorescent dye is used in safety demonstrations and to quantify dermal exposure.•Ability of safety demonstrations to reduce future exposure is unproven.•Prior dye experience was associated with less contamination vs. dye-naïve controls.•Community interventions that include tracer dye may help reduce agrochemical exposure.
B-cell receptor (BCR) signaling plays a key role in the behavior of chronic lymphocytic leukemia (CLL). However, cellular consequences of signaling are incompletely defined. Here we explored possible ...links between BCR signaling and the unfolded protein response (UPR), a stress response pathway that can promote survival of normal and malignant cells. Compared with normal B cells, circulating CLL cells expressed increased, but variable, levels of UPR components. Higher expression of CHOP and XBP1 RNAs was associated with more aggressive disease. UPR activation appeared due to prior tissue-based antigenic stimulation because elevated expression of UPR components was detected within lymph node proliferation centers. Basal UPR activation also correlated closely with surface immunoglobulin M (sIgM) signaling capacity in vitro in both IGHV unmutated CLL and within mutated CLL. sIgM signaling increased UPR activation in vitro with responders showing increased expression of CHOP and XBP1 RNAs, and PERK and BIP proteins, but not XBP1 splicing. Inhibitors of BCR-associated kinases effectively prevented sIgM-induced UPR activation. Overall, this study demonstrates that sIgM signaling results in activation of some components the UPR in CLL cells. Modulation of the UPR may contribute to variable clinical behavior, and its inhibition may contribute to clinical responses to BCR-associated kinase inhibitors.
•Stimulation of the B-cell receptor of chronic lymphocytic leukemia cells results in activation of an unfolded protein response.•Unfolded protein response activation following surface immunoglobulin M stimulation in vitro is dependent on the activity of BTK and SYK.
We describe successful efforts to optimize the in vivo profile and address off-target liabilities of a series of BACE1 inhibitors represented by 6 that embodies the recently validated fused ...pyrrolidine iminopyrimidinone scaffold. Employing structure-based design, truncation of the cyanophenyl group of 6 that binds in the S3 pocket of BACE1 followed by modification of the thienyl group in S1 was pursued. Optimization of the pyrimidine substituent that binds in the S2′–S2″ pocket of BACE1 remediated time-dependent CYP3A4 inhibition of earlier analogues in this series and imparted high BACE1 affinity. These efforts resulted in the discovery of difluorophenyl analogue 9 (MBi-4), which robustly lowered CSF and cortex Aβ40 in both rats and cynomolgus monkeys following a single oral dose. Compound 9 represents a unique molecular shape among BACE inhibitors reported to potently lower central Aβ in nonrodent preclinical species.
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