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Neutrophils, monocytes and the endothelium are critical to ANCA-associated vasculitis (AAV) pathogenesis. This study aimed to develop a 4-dimensional (4D) live-cell imaging system that would enable investigation of spatial and temporal dynamics of these cells in health and disease. We further aimed to validate this system using autologous donor serum from AAV patients and polyclonal ANCA IgG, as well as exploring its potential in the pre-clinical testing of putative therapeutic compounds. Neutrophils and monocytes were isolated from peripheral venous blood of AAV patients or healthy controls and co-incubated on an endothelial monolayer in the presence of autologous serum. Alternatively, polyclonal ANCA IgG was used, following TNF-α priming, and imaged in 4-dimensions for 3 h using a spinning disc confocal microscope. Volocity 6.3 ® analysis software was used for quantification of leukocyte dynamics. The use of autologous serum resulted in increased neutrophil degranulation ( p  = .002), transmigration ( p  = .0096) and monocyte transcellular transmigration ( p  = .0013) in AAV patients. Polyclonal MPO-ANCA IgG induced neutrophil degranulation ( p  < .001) in this system. C5aR1 antagonism reduced neutrophil degranulation ( p  < .0002). We have developed a novel 4D in vitro system that allows accurate quantification of multiple neutrophil- and monocyte-endothelial interactions in AAV in a single assay. This system has the potential to highlight dynamics key to pathophysiology of disease, as well investigating the impact of potential therapeutics on these functions.

Objective: To investigate the potential structural and metabolic role of skeletal muscle in systemic lupus erythematosus (SLE)-related fatigue., Methods: A case-control, multimodal magnetic resonance imaging (MRI) study was conducted. Cases were patients with inactive SLE who reported chronic fatigue. Controls were age- and sex-matched healthy members of the general population. Patients were clinically characterized and then underwent a 3T whole-body MRI scan. Resting and dynamic 31 P MRI spectroscopy of the calf muscles was applied, from which phosphocreatine (PCr) recovery halftime, a marker of mitochondrial dysfunction, was computed. In addition, microstructural sequences (T1-weighted anatomic images, T2 mapping, and diffusion tensor imaging) were acquired. Descriptive statistics evaluated group differences and within-case physical fatigue correlations were explored., Results: Of the 37 recruits (mean age 43.8 years, 89.2% female), cases (n = 19) reported higher levels of physical fatigue, pain, depression, and sleep disturbance compared to the control group (P < 0.0001). PCr was greater (P = 0.045) among cases (mean ± SD 33.0 ± 9.0 seconds) compared to controls (mean ± SD 27.1 ± 6.6 seconds). No microstructural group differences were observed. Within cases, physical fatigue did not correlate with PCr (r = -0.28, P = 0.25)., Conclusion: We report preliminary data demonstrating greater skeletal muscle mitochondrial dysfunction among fatigued patients with SLE compared to healthy controls., (© 2019, American College of Rheumatology.)

Importance: The population of infants, children, and adolescents cared for at pediatric long-term care facilities is increasing in complexity and size and thus consumes substantial health care resources. Infections are a significant cause of morbidity and mortality in this population, but few recent data describe their incidence and effects., Objectives: To describe the types of infections diagnosed in residents of pediatric long-term care facilities, calculate infection rates, and identify risk factors for respiratory tract infections (RTIs)., Design, Setting, and Participants: This prospective cohort study, which was part of a larger trial called Keep It Clean for Kids, was conducted from September 1, 2012, to December 31, 2015, at 3 pediatric long-term care facilities in New York. Residents of the facilities who were 21 years or younger and either residents or admitted during the study period (n = 717) were enrolled in the study. Medical records were reviewed to identify infections diagnosed by site clinicians., Main Outcomes and Measures: Incidence of infections, such as RTIs; skin and soft-tissue infections; chronic comorbid conditions, including neurologic and respiratory disorders; and device use, including gastrostomy tubes and tracheostomies, was determined. Risk factors for RTIs were assessed by generalized linear mixed method regression modeling., Results: The 717 residents had a median (interquartile range) age at enrollment of 2.6 (0.4-9.1) years; 358 (49.9%) were male. Four hundred twenty-eight residents (59.7%) had feeding tubes and 215 (30.0%) had tracheostomies. Most chronic comorbid conditions were musculoskeletal or ambulation (532 residents [74.2%]), neurologic (505 [70.4%]), respiratory (361 [50.3%]), and gastrointestinal (230 [32.1%]) disorders, and 460 residents (64.2%) had 4 or more chronic comorbid conditions. Site clinicians diagnosed 2052 infections during the 3-year study period. Respiratory tract infections were most common and were diagnosed in 1291 residents (62.9%). The overall infection rate was 5.3 infections per 1000 resident-days, and RTI rates were 3.3 infections per 1000 resident-days. Overall infection rates and rates of RTI, skin and soft-tissue infection, urinary tract infection, and bloodstream infection varied among the 3 sites. In the multivariable model, younger age (incidence rate ratio [IRR], 1.05; 95% CI, 1.03-1.06), increased number of chronic comorbid conditions (IRR, 1.12; 95% CI, 1.06-1.19), and the use of feeding tubes (IRR, 1.34; 95% CI, 1.03-1.64) and tracheostomies (IRR, 1.40; 95% CI, 1.17-1.69) were associated with RTIs., Conclusions and Relevance: In this study, RTIs were the most common infections diagnosed, but modifiable risk factors for RTIs were not identified. Future work should focus on optimizing infection prevention and control strategies to reduce infections, particularly RTIs, in the pediatric long-term care population.

Background: Studies in adult long-term care facilities (LTCFs) have shown a correlation between hand hygiene (HH) and viral outbreak reduction, but no such studies have been conducted in pediatric LTCFs where the epidemiology of viral pathogens is different., Methods: We compared electronically monitored facility-wide HH frequency in the weeks immediately prior to outbreaks of acute respiratory or gastrointestinal infections versus control weeks in a 137-bed pediatric LTCF from October 2012-August 2015. Control weeks were the 8-14 day (control 1) and 15-21 day (control 2) periods prior to the onset of each outbreak., Results: There was no difference in HH frequency in the weeks leading up to the outbreaks versus control weeks (odds ratio [OR], 1.0; 95% confidence interval CI, 1.00-1.001 using control 1 and OR, 1.0; 95% CI, 1.00-1.001 using control 2)., Conclusions: Our findings differed from those in adult LTFCs, possibly because of the greater contact between residents and staff in the pediatric setting, increased susceptibility to viral pathogens because of immunologic immaturity, or differences in the types of pathogens prevalent in each setting. Although HH may be important for limiting the number of residents infected during outbreaks, we found no association between HH frequency and subsequent outbreak onset., (Copyright © 2016 Association for Professionals in Infection Control and Epidemiology, Inc. Published by Elsevier Inc. All rights reserved.)

We evaluated the collective impact of several infection prevention and control initiatives aimed at reducing acute respiratory infections (ARIs) in a pediatric long-term care facility. ARIs did not decrease overall, though the proportion of infections associated with outbreaks and average number of cases per outbreak decreased. Influenza rates decreased significantly. Infect Control Hosp Epidemiol 2016;37:859-862., Competing Interests: Potential conflicts of interest: All authors report no conflicts of interest relevant to this article.

Acute respiratory tract infections (ARI) are a major burden in pediatric long-term care. We analyzed the financial impact of ARI in 2012-2013. Costs associated with ARI during the respiratory viral season were ten times greater than during the non-respiratory viral season, $31 224 and $3242 per 1000 patient-days, respectively (P < 0·001). ARI are burdensome for pediatric long-term care facilities not only because of the associated morbidity and mortality, but also due to the great financial costs of prevention., (© 2015 The Authors. Influenza and Other Respiratory Viruses Published by John Wiley & Sons Ltd.)

Pediatric long-term care facilities (pLTCFs) provide for children with chronic, complex medical needs and therefore face unique challenges for infection prevention and control (IP&C). At a conference in 2012, pLTCF providers reported IP&C issues of greatest concern in a survey. Major concerns included the lack of IP&C best practice guidelines, multidrug-resistant bacteria, and viral respiratory infections. Best practice guidelines for IP&C specific to pLTCF populations should be developed and evaluated., (Copyright © 2014 Association for Professionals in Infection Control and Epidemiology, Inc. Published by Elsevier Inc. All rights reserved.)

Background: Viral respiratory pathogens cause outbreaks in pediatric long-term care facilities (LTCFs), but few studies have used viral diagnostic testing to identify the causative pathogens. We describe the use of such testing during a prolonged period of respiratory illness and elucidate the epidemiology of human metapneumovirus (hMPV) at our LTCF., Design: Retrospective study of influenza-like illness (ILI)., Setting: A 136-bed pediatric LTCF from January 1 through April 30, 2010., Methods: The ILI case definition included fever, cough, change in oropharyngeal secretions, increase in oxygen requirement, and/or wheezing., Results: During the study period, 69 episodes of ILI occurred in 61 (41%) of 150 residents. A viral pathogen was detected in 27 (39%) of the episodes, including respiratory syncytial virus (RSV) (n = 3), influenza A virus (not typed; n = 2), parainfluenza virus (n =2), adenovirus (n = 1), and hMPV (n = 19). Twenty-seven of the residents with ILI (44%) required transfer to acute care hospitals (mean length of hospitalization, 12 days; range, 3-47 days). Residents with tracheostomies were more likely to have ILI (adjusted odds ratio [OR], 3.99 [95% confidence interval {CI}, 1.87-8.53]; P = .0004). The mortality rate for residents with ILI was 1.6%. Residents with hMPV were younger (P = .03), more likely to be transferred to an acute care facility (OR, 3.73 [95% CI, 1.17-11.95]; P = .02), and less likely to have a tracheostomy (adjusted OR, 0.19 [95% CI, 0.047-0.757]; P = .02 )., Discussion: Diverse pathogens, most notably hMPV, caused ILI in our pediatric LTCF during a prolonged period of time. Viral testing was helpful in characterizing the epidemiology of ILI in this population.

Purpose: The aim of this work was to optimize biodegradable polyester poly(glycerol adipate-co-ω-pentadecalactone), PGA-co-PDL, microparticles as sustained release (SR) carriers for pulmonary drug delivery., Methods: Microparticles were produced by spray drying directly from double emulsion with and without dispersibility enhancers ((L)-arginine and (L)-leucine) (0.5-1.5%w/w) using sodium fluorescein (SF) as a model hydrophilic drug., Results: Spray-dried microparticles without dispersibility enhancers exhibited aggregated powders leading to low fine particle fraction (%FPF) (28.79 ± 3.24), fine particle dose (FPD) (14.42 ± 1.57 μg), with a mass median aerodynamic diameter (MMAD) 2.86 ± 0.24 μm. However, (L)-leucine was significantly superior in enhancing the aerosolization performance ((L-)arginine:%FPF 27.61 ± 4.49-26.57 ± 1.85; FPD 12.40 ± 0.99-19.54 ± 0.16 μg and MMAD 2.18 ± 0.35-2.98 ± 0.25 μm, (L)-leucine:%FPF 36.90 ± 3.6-43.38 ± 5.6; FPD 18.66 ± 2.90-21.58 ± 2.46 μg and MMAD 2.55 ± 0.03-3.68 ± 0.12 μm). Incorporating (L)-leucine (1.5%w/w) reduced the burst release (24.04 ± 3.87%) of SF compared to unmodified formulations (41.87 ± 2.46%), with both undergoing a square root of time (Higuchi's pattern) dependent release. Comparing the toxicity profiles of PGA-co-PDL with (L)-leucine (1.5%w/w) (5 mg/ml) and poly(lactide-co-glycolide), (5 mg/ml) spray-dried microparticles in human bronchial epithelial 16HBE14o- cell lines, resulted in cell viability of 85.57 ± 5.44 and 60.66 ± 6.75%, respectively, after 72 h treatment., Conclusion: The above data suggest that PGA-co-PDL may be a useful polymer for preparing SR microparticle carriers, together with dispersibility enhancers, for pulmonary delivery.

Nanomaterials and their associated technologies hold promising opportunities for the development of new materials and applications in a wide variety of disciplines, including medicine, environmental remediation, waste treatment, and energy conservation. However, current information regarding the environmental effects and health risks associated with nanomaterials is limited and sometimes contradictory. This article summarizes the conclusions of a 2008 NATO workshop designed to evaluate the wide-scale implications (e.g., benefits, risks, and costs) of the use of nanomaterials on human health and the environment. A unique feature of this workshop was its interdisciplinary nature and focus on the practical needs of policy decision makers. Workshop presentations and discussion panels were structured along four main themes: technology and benefits, human health risk, environmental risk, and policy implications. Four corresponding working groups (WGs) were formed to develop detailed summaries of the state-of-the-science in their respective areas and to discuss emerging gaps and research needs. The WGs identified gaps between the rapid advances in the types and applications of nanomaterials and the slower pace of human health and environmental risk science, along with strategies to reduce the uncertainties associated with calculating these risks.

Ibuprofen was conjugated at different levels to a novel polyester, poly(glycerol-adipate-co-omega-pentadecalactone) (PGA-co-PL), via an ester linkage to form a prodrug. The conjugates were characterized by differential scanning calorimetry (DSC), nuclear magnetic resonance (NMR), infrared (IR), gel permeation chromatography (GPC), ultraviolet (UV), and high-performance liquid chromatography (HPLC). The conjugates had a molecular weight between 18 and 24 kDa, and there was a suppression of the free hydroxyl groups within the conjugated polymer. DSC scans showed a lowering of the melting point (T(m)) when compared with the polyester alone and a difference in the number and area of T(m) peaks. Drug release studies showed an initial burst release (13-18%) followed thereafter by very slow release (maximum 35% after 18 days). Continuous work may produce ester-linked conjugates that are sufficiently labile to allow for complete release of ibuprofen over the time period studied.

Regulatory initiatives relating to biotechnology-derived livestock have focused on animal health, environmental impact, and the general concept of the safety of the food and by-products derived from such animals. Existing regulatory frameworks have been stretched to accommodate these emerging concerns. Public concerns and the expectations of society mean that the regulatory infrastructure is subject to a high level of scrutiny and that regulations are expected to maintain a clear level of confidence, transparency and effectiveness. A sound regulatory regime should be 'neutral', neither 'facilitating' nor 'restricting' the approval of products or by-products derived from biotechnology-derived animals.

The twin-arginine translocation (Tat) pathway is a system with the unique ability to export proteins in a fully folded conformation. Its main components are TatA, TatB and TatC, all of which are required for Tat-dependent export. The Tat pathway is found in several Archaea, and in most of them a moderate number of predicted Tat-dependent substrates are present. Putative substrates include those binding cofactors such as iron-sulphur clusters and molybdopterin. In these Archaea, the role of the Tat pathway seems to be similar to that of bacteria: the export of a small subset of proteins that fold before translocation across the cytoplasmic membrane. The exception to this is the Tat system of the halophilic archaeon Halobacterium sp. NRC-1. In this organism, the majority of extra-cytoplasmic proteins are predicted to use the Tat pathway, which is, most likely, a specific adaptation to its particular lifestyle in highly saline conditions.

A novel deuterium ((2)H) NMR technique as developed for measuring the total number of deuterons exchanged by lyophilised protein samples following hydrogen-deuterium (H-D) exchange. Using this methodology differences in the H-D exchange behaviour of the proteolytic enzyme subtilisin Carlsberg hydrated either in air or an organic solvent were probed as a function of hydration. At low thermodynamic water activity (a(w)), the degree of H-D exchange increased rapidly with hydration (from anhydrous to a(w) 0.22). At a(w) 0.22, subtilisin powders hydrated in air were found to have reached an H-D exchange level comparable to that found upon aqueous dissolution and in agreement with previous studies using lysozyme. Lyophilised subtilisin hydrated in either dichloromethane (DCM) or diisopropyl ether (DIPE) showed a pattern of exchange (vs. a(w)) comparable to that found for powders hydrated in air. However, subtilisin hydrated in n-hexane showed a significant reduction in H-D exchange at all a(w) studied. Control experiments demonstrated that the reduction in H-D exchange observed for subtilisin in n-hexane was not a kinetic effect. This lower level of exchange in n-hexane implies that hydrated subtilisin Carlsberg has a lower conformational motility and more rigid protein matrix., (Copyright 2000 John Wiley & Sons, Inc. Biotechnol Bioeng 70: 262-269, 2000.)

Programmable fusogenic vesicles (PFVs) are lipid-based drug-delivery systems that exhibit time-dependent destabilization. The rate at which this destabilization occurs is determined by the exchange rate of a bilayer-stabilizing component, polyethylene glycol-phosphatidylethanolamine (PEG-PE) from the vesicle surface. This exchange rate is controlled, in turn, by the acyl chain composition of the PEG-PE. We describe in vitro and in vivo studies using PFVs as delivery vehicles for the anticancer drug mitoxantrone. We demonstrate that the PEG-PE acyl composition determined the rate at which PFVs are eliminated from plasma after intravenous administration, and the rate of mitoxantrone leakage from PFV. The nature of the PEG-PE component also determined the antitumor efficacy of mitoxantrone-loaded PFV in murine and human in murine and human xenograft tumor models. Increased circulation time and improved activity were obtained for PFV containing PEG-PE with an 18-carbon acyl chain length, as a result of slower vesicle destabilization.

Twenty infants and children with positive serologic tests for the human T-cell lymphotropic virus type III (HTLV-III) were noted to have similar features including growth failure (75%), microcephaly (70%), and craniofacial abnormalities consisting of ocular hypertelorism (50%); prominent box-like appearance of the forehead (75%); flat nasal bridge (70%); mild upward or downward obliquity of the eyes (65%); long palpebral fissures with blue sclerae (60%); short nose with flattened columella and well-formed, triangular philtrum (65%); and patulous lips (60%). These features constitute a new and distinct dysmorphic syndrome, the HTLV-III embryopathy.