In Silico Study of the Early Stages of Aggregation of ß-Sheet Forming Antimicrobial Peptide GL13K.

Antimicrobial peptides (AMPs) are of growing interest as potential candidates that may offer more resilience against antimicrobial resistance than traditional antibiotic agents. In this article, we perform the first in silico study of the synthetic ß sheet-forming AMP GL13K. Through atomistic simulations of single and multi-peptide systems under different conditions, we are able to shine a light on the short timescales of early aggregation. We find that isolated peptide conformations are primarily dictated by sequence rather than charge, whereas changing charge has a significant impact on the conformational free energy landscape of multi-peptide systems. We demonstrate that the loss of charge-charge repulsion is a sufficient minimal model for experimentally observed aggregation. Overall, our work explores the molecular biophysical underpinnings of the first stages of aggregation of a unique AMP, laying necessary groundwork for its further development as an antibiotic candidate.

Hypoxemia After Endobronchial Valve Deployment for Persistent Air Leak.

Endobronchial valves (EBVs) are a novel, minimally invasive bronchoscopic management technique for persistent air leaks that fail conservative therapy. Currently, 2 EBVs are available in the United States: the Spiration Valve System (Olympus, Redmond, WA) and the Zephyr Valve (Pulmonx, Redwood, CA). These valves are Food and Drug Administration-approved to reduce hyperinflation in emphysematous patients via bronchoscopic lung-volume reduction. However, more recently, the Spiration Valve has been granted a compassionate use exemption through the Food and Drug Administration for persistent postsurgical air leaks. Despite their popularity, these devices are not free from side effects. As an anesthesiologist, it is vital to be aware of the pathophysiology of this patient population so that safe and effective anesthetics may be provided during valve placement. Here, the use of EBVs is discussed in a patient who presented with a persistent air leak after a transthoracic needle aspiration that failed treatment due to persistent hypoxemia, warranting EBV removal.

Does Forgiveness Enhance Or Detract From Relationship Quality Among Sexual Abuse Survivors?

Many women experience childhood sexual abuse (CSA) during their childhood and CSA often negatively impacts adult's romantic relationships. Consequently, it is important to understand the protective factors that buffer against the detrimental impact of CSA on the quality of women's romantic relationships. Forgiveness may be one such factor. The current study looked at trait forgiveness as a moderator of CSA and overall relationship quality, positive relationship quality, and negative relationship quality. A sample of 171 women completed an online survey. Using hierarchical regression, forgiveness was found to moderate the association between CSA and overall relationship quality and negative relationship quality, but not positive relationship quality. Findings indicate that the interaction between CSA and forgiveness was significant, but higher levels of forgiveness actually decreased overall relationship quality and increased negative relationship quality. The relationship between CSA and overall reports of relationship quality and negative relationship quality were stable at low levels of forgiveness, but when forgiveness was high overall relationship quality decreased and negative relationship quality increased. CSA was also directly associated with lower levels of positive relationship quality. Findings from the study indicate continued conceptual refinement when considering CSA, forgiveness, and relationship quality.

VapA of Rhodococcus equi binds phosphatidic acid.

Rhodococcus equi is a multihost, facultative intracellular bacterial pathogen that primarily causes pneumonia in foals less than six months in age and immunocompromised people. Previous studies determined that the major virulence determinant of R. equi is the surface bound virulence associated protein A (VapA). The presence of VapA inhibits the maturation of R. equi-containing phagosomes and promotes intracellular bacterial survival, as determined by the inability of vapA deletion mutants to replicate in host macrophages. While the mechanism of action of VapA remains elusive, we show that soluble recombinant VapA32-189 both rescues the intramacrophage replication defect of a wild type R. equi strain lacking the vapA gene and enhances the persistence of nonpathogenic Escherichia coli in macrophages. During macrophage infection, VapA was observed at both the bacterial surface and at the membrane of the host-derived R. equi containing vacuole, thus providing an opportunity for VapA to interact with host constituents and promote alterations in phagolysosomal function. In support of the observed host membrane binding activity of VapA, we also found that rVapA32-189 interacted specifically with liposomes containing phosphatidic acid in vitro. Collectively, these data demonstrate a lipid binding property of VapA, which may be required for its function during intracellular infection.

Pharmacokinetic and pharmacodynamic evaluation of AZD5847 in a mouse model of tuberculosis.

AZD5847, a novel oxazolidinone with an MIC of 1 µg/ml, exhibits exposure-dependent killing kinetics against extracellular and intracellular Mycobacterium tuberculosis. Oral administration of AZD5847 to mice infected with M. tuberculosis H37Rv in a chronic-infection model resulted in a 1.0-log10 reduction in the lung CFU count after 4 weeks of treatment at a daily area under the concentration-time curve (AUC) of 105 to 158 µg · h/ml. The pharmacokinetic-pharmacodynamic parameter that best predicted success in an acute-infection model was an AUC for the free, unbound fraction of the drug/MIC ratio of ≥ 20. The percentage of time above the MIC in all of the efficacious regimens was 25% or greater.

Microfabricated gas chromatograph for rapid, trace-level determinations of gas-phase explosive marker compounds.

A prototype microfabricated gas chromatograph (µGC) adapted specifically for the rapid determination of selected gas-phase marker compounds of the explosive 2,4,6-trinitrotoluene (TNT) at sub-parts-per-billion (

Pathology and Neurotoxicity in Dogs after Repeat Dose Exposure to a Serotonin 5-HT1B Inhibitor.

AZD3783, a cationic amphiphilic drug and a potent inhibitor of the 5-hydroxytryptamine (5-HT1B) receptor, was explored as a potential treatment for depression. To support clinical trials, repeat dose toxicity studies in rats and dogs were conducted. Here we report toxicity findings in dogs after dosing from 1 to 3 months. In the 1-month study, there were minimal neuronal vacuolation in the brain, a marked increase in liver enzymes accompanied by hepatocellular degeneration/necrosis and phospholipidosis (PLD), and PLD/cholecystitis in the gallbladder of animals dosed at 47 mg/kg/day. In the 3-month study, neurotoxicity resulted in euthanasia of one animal dosed at 30 mg/kg/day after 86 days. Extensive pathologic changes were seen in all animals in retina epithelium (inclusion bodies), brain (neuronal vacuolation, degeneration, or necrosis and nerve fiber degeneration), spinal ganglia (vacuolation, degeneration, or necrosis), as well as sciatic and optic nerves (degeneration). Pigment-laden macrophages were observed in the lung, kidney, liver, gallbladder, bone marrow, gastrointestinal tract, and lymphoid tissues. Also seen were vitrel and retinal hemorrhage in the eyes. A brain concentration and pathology study showed that the concentration of AZD3783 in the brain was approximately 4 times higher than in the plasma after 4 weeks of dosing, however, they were similar in all regions examined, and did not correlate with areas with pathologic findings. Our findings with AZD3783 in dogs have not been reported previously with other CNS compounds that effect through serotonergic pharmacology.

Identifying Drivers and Barriers to Precepting Midwifery Students: "A Little Part of Me Lives on in Each Student Midwife".

INTRODUCTION: Increased access to midwifery care is one strategy that could improve perinatal health outcomes and help address the maternal health crisis in the United States. A modifiable barrier to increasing the workforce is greater access to midwifery preceptors for clinical training. The objective of this research is to use the socioecological framework to identify midwives' perceptions of the barriers and facilitators to precepting students in clinical areas. METHODS: Midwives attending a preceptor education and training workshop series responded to 3 different questions at the end of each session: (1) What makes precepting midwifery students challenging? (2) What makes precepting midwifery students possible? and (3) What makes precepting midwifery students worthwhile? Responses were coded to align with the socioecological framework, which distinguishes individual, interpersonal, community, institutional, and policy-level influences. RESULTS: Midwives' responses were spread across the levels of the socioecological model except for policy. Participants identified institutional influences such as support as factors that made precepting feasible, both individual and interpersonal factors such as time constraints as areas that presented challenges to precepting, and community factors, like the joy of sharing midwifery, contributing to what made precepting worthwhile. DISCUSSION: Multiple levels of influence were identified in the preceptor process. Participants were internally motivated to precept while also articulating that to make precepting possible, there is a need for support from both colleagues and the greater systems within which they worked. Further studies are needed to investigate an ecosystem that facilitates an effective and sustainable model for midwifery precepting. Additionally, there is a need for efforts to engage and educate midwives in clinical practice about government advocacy that could actualize policy initiatives to support clinical midwifery education.

Dyadic parent-adolescent relationship quality as pathways from maternal childhood abuse to adolescent psychopathology.

Children of maternal caregivers abused in childhood are at increased risk for mental health problems including anxiety and depression. To date, most studies exploring the intergenerational transmission of trauma have focused on younger children, with far fewer studies investigating adolescent mental health. Previous research suggests that maternal childhood abuse negatively impacts the parent-adolescent relationship, which may contribute to the development and maintenance of adolescent mental health problems. The current study examined dyadic reports of maternal-adolescent relationship quality as mediators linking maternal reports of childhood abuse to adolescent depression and anxiety. The bootstrapped indirect effects from maternal childhood abuse to adolescent symptoms of anxiety and depression were significant through adolescent reports of relationship quality, but not through maternal reports of relationship quality. Findings suggest that an adolescent's perception of their maternal-adolescent relationship may mediate the relationship between their maternal caregiver's childhood abuse and their own symptoms of anxiety and depression.

Pulmonary artery dissection in long standing idiopathic pulmonary arterial hypertension: A case report.

Pulmonary arterial dissection (PAD) is a rare and often lethal complication of chronic pulmonary arterial hypertension (PAH), which may occurs in patients with idiopathic pulmonary arterial hypertension (IPAH) and potentially in those with connective tissue disorders. While rare, sudden death often occurs secondary to acute cardiac tamponade, as the pulmonary artery dissects into the pericardium; this diagnosis is often made postmortem. Nevertheless, with the proliferation of multidetector computed tomography (MDCT) as a diagnostic test, patients may be identified very early after symptom onset, prompting rapid intervention with decreased morbidity and mortality. We report a case of IPAH complicated by pulmonary artery aneurysm (PAA) and PAD, diagnosed by CT pulmonary angiogram (CTPA), and treated with bilateral lung transplantation, pulmonic valve replacement, and re-anastomosis of the donor main PA to a pulmonary valve conduit.

The TNF-Alpha Inducing Protein is Associated With Gastric Inflammation and Hyperplasia in a Murine Model of Helicobacter pylori Infection.

Helicobacter pylori (H. pylori) is a Gram-negative bacterium that colonizes the human stomach leading to the development of chronic gastritis, peptic ulcers and gastric adenocarcinoma. A combination of host, environment and bacterial virulence factors contribute to disease development. The H. pylori TNFα inducing protein (Tipɑ) is a virulence factor shown to induce multiple pro-inflammatory cytokines in addition to TNFα in vitro. The goal of the present study was to elucidate the role of Tipα in promoting inflammation in vivo and to identify the molecular pathways associated with Tipα associated virulence. Mice were infected with wild-type Sydney strain (SS1) or a tipα mutant (Δtipα) for 1 month and 4 months. We also completed a second 4 months infection including a 1:1 SS1 to Δtipα co-infected group in addition to SS1 and Δtipα infected groups. The expression of TNFα, and KC were significantly higher in the SS1 infected group compared to both uninfected control (naïve) and Δtipα groups. Mice infected with Tipα expressing SS1 induced more severe histological gastritis and developed hyperplasia compared to Δtipα infected mice. Microarray analysis of gastric epithelial cells co-cultured with recombinant Tipα (rTipα) demonstrates up-regulation of the NFκB pathway. This data suggest Tipα plays an important role in H. pylori induced inflammation.

Oxidative lipidomics of hyperoxic acute lung injury: mass spectrometric characterization of cardiolipin and phosphatidylserine peroxidation.

Reactive oxygen species have been shown to play a significant role in hyperoxia-induced acute lung injury, in part, by inducing apoptosis of pulmonary endothelium. However, the signaling roles of phospholipid oxidation products in pulmonary endothelial apoptosis have not been studied. Using an oxidative lipidomics approach, we identified individual molecular species of phospholipids involved in the apoptosis-associated peroxidation process in a hyperoxic lung. C57BL/6 mice were killed 72 h after exposure to hyperoxia (100% oxygen). We found that hyperoxia-induced apoptosis (documented by activation of caspase-3 and -7 and histochemical terminal deoxynucleotidyl transferase dUTP-mediated nick-end labeling staining of pulmonary endothelium) was accompanied by nonrandom oxidation of pulmonary lipids. Two anionic phospholipids, mitochondria-specific cardiolipin (CL) and extramitochondrial phosphatidylserine (PS), were the two major oxidized phospholipids in hyperoxic lung. Using electrospray ionization mass spectrometry, we identified several oxygenation products in CL and PS. Quantitative assessments revealed a significant decrease of CL and PS molecular species containing C(18:2), C(20:4), C(22:5), and C(22:6) fatty acids. Similarly, exposure of mouse pulmonary endothelial cells (MLEC) to hyperoxia (95% oxygen; 72 h) resulted in activation of caspase-3 and -7 and significantly decreased the content of CL molecular species containing C(18:2) and C(20:4) as well as PS molecular species containing C(22:5) and C(22:6). Oxygenated molecular species were found in the same two anionic phospholipids, CL and PS, in MLEC exposed to hyperoxia. Treatment of MLEC with a mitochondria-targeted radical scavenger, a conjugate of hemi-gramicidin S with nitroxide, XJB-5-131, resulted in significantly lower oxidation of both CL and PS and a decrease in hyperoxia-induced changes in caspase-3 and -7 activation. We speculate that cytochrome c driven oxidation of CL and PS is associated with the signaling role of these oxygenated species participating in the execution of apoptosis and clearance of pulmonary endothelial cells, thus contributing to hyperoxic lung injury.

The AVMA's definitions of antimicrobial uses for prevention, control, and treatment of disease.

Recent state and federal legislative actions and current recommendations from the World Health Organization seem to suggest that, when it comes to antimicrobial stewardship, use of antimicrobials for prevention, control, or treatment of disease can be ranked in order of appropriateness, which in turn has led, in some instances, to attempts to limit or specifically oppose the routine use of medically important antimicrobials for prevention of disease. In contrast, the AVMA Committee on Antimicrobials believes that attempts to evaluate the degree of antimicrobial stewardship on the basis of therapeutic intent are misguided and that use of antimicrobials for prevention, control, or treatment of disease may comply with the principles of antimicrobial stewardship. It is important that veterinarians and animal caretakers are clear about the reason they may be administering antimicrobials to animals in their care. Concise definitions of prevention, control, and treatment of individuals and populations are necessary to avoid confusion and to help veterinarians clearly communicate their intentions when prescribing or recommending antimicrobial use.

Neutral 5-substituted 4-indazolylaminoquinazolines as potent, orally active inhibitors of erbB2 receptor tyrosine kinase.

We have identified a new series of C-5 substituted indazolylaminoquinazolines as potent erbB2 kinase inhibitors. The lead compound 22 showed excellent in vitro potency, good physical properties, acceptable oral pharmacokinetics in rat and dog, and low human in vitro clearance. It showed at least equivalent activity dose for dose compared to lapatinib in various erbB2- or EGFR-driven xenograft models after chronic oral administration.

The attention training technique, self-focused attention, and anxiety: a laboratory-based component study.

Self-focused attention is an important target of intervention within Wells's (2009) metacognitive therapy and the attention training technique (ATT) is one component of metacognitive therapy that purportedly alters focus of attention. However, we do not yet fully understand whether ATT causes changes in focus of attention, the effectiveness of ATT compared to other techniques in reducing self-focused attention, and how ATT leads to its therapeutic gains. A laboratory-based component study was completed to address these gaps in the literature. Nonclinical participants were randomly assigned to one session of ATT (n = 38) or a mindfulness-based task (n = 38). ATT and the mindfulness-based task differentially changed focus of attention, with ATT causing greater external focus of attention and the mindfulness-based task causing greater self-focused attention from pre-to-post manipulation. ATT and the mindfulness-based task both led to reductions in anxiety. Reductions in self-focused attention were related to less anxiety following ATT, whereas increases in self-focused attention were related to less anxiety following the mindfulness-based task. Conceptual and therapeutic implications are discussed.

Genome-wide association mapping and identification of candidate genes for the rumpless and ear-tufted traits of the Araucana chicken.

Araucana chickens are known for their rounded, tailless rumps and tufted ears. Inheritance studies have shown that the rumpless (Rp) and ear-tufted (Et) loci each act in an autosomal dominant fashion, segregate independently, and are associated with an increased rate of embryonic mortality. To find genomic regions associated with Rp and Et, we generated genome-wide SNP profiles for a diverse population of 60 Araucana chickens using the 60 K chicken SNP BeadChip. Genome-wide association studies using 40 rumpless and 11 tailed birds showed a strong association with rumpless on Gga 2 (P(raw) = 2.45×10(-10), P(genome) = 0.00575), and analysis of genotypes revealed a 2.14 Mb haplotype shared by all rumpless birds. Within this haplotype, a 0.74 Mb critical interval containing two Iroquois homeobox genes, Irx1 and Irx2, was unique to rumpless Araucana chickens. Irx1 and Irx2 are central for developmental prepatterning, but neither gene is known to have a role in mechanisms leading to caudal development. A second genome-wide association analysis using 30 ear-tufted and 28 non-tufted birds revealed an association with tufted on Gga 15 (P(raw) = 6.61×10(-7), P(genome) = 0.0981). We identified a 0.58 Mb haplotype common to tufted birds and harboring 7 genes. Because homozygosity for Et is nearly 100% lethal, we employed a heterozygosity mapping approach to prioritize candidate gene selection. A 60 kb region heterozygous in all Araucana chickens contains the complete coding sequence for TBX1 and partial sequence for GNB1L. TBX1 is an important transcriptional regulator of embryonic development and a key genetic determinant of human DiGeorge syndrome. Herein, we describe localization of Rp and Et and identification of positional candidate genes.

Neutral 5-substituted 4-anilinoquinazolines as potent, orally active inhibitors of erbB2 receptor tyrosine kinase.

Neutral 5-substituted 4-anilinoquinazolines addressed high in vivo clearance and phospholipidosis associated with previous basic compounds. A representative compound 8a inhibited tumor growth in a mouse xenograft model when co-administered with the cytochrome P450 inhibitor 1-aminobenzotriazole (ABT), and data are consistent with pharmacology primarily reflecting inhibition of erbB2 receptor tyrosine kinase.

A requirement for dimerization of HP1Hsalpha in suppression of breast cancer invasion.

The development and progression of cancer is controlled by gene expression, often regulated through chromatin packaging. Heterochromatin protein 1(Hsalpha) (HP1(Hsalpha)), one of three human HP1 family members, participates in heterochromatin formation and gene regulation. HP1(Hsalpha) possesses an amino-terminal chromodomain, which binds methylated lysine 9 of histone H3 (meK9 H3), and a carboxyl-terminal chromoshadow domain (CSD) that is required for dimerization and interaction with partner proteins. HP1(Hsalpha) is down-regulated in invasive metastatic breast cancer cells compared with poorly invasive nonmetastatic breast cancer cells. Expression of EGFP-HP1(Hsalpha) in highly invasive MDA-MB-231 cells causes a reduction in in vitro invasion, without affecting cell growth. Conversely, knock-down of HP1(Hsalpha) levels in the poorly invasive breast cancer cell line MCF-7 increased invasion, without affecting cell growth. To determine whether functions of the CSD were required for the regulation of invasion, mutant forms of HP1(Hsalpha) were expressed in MDA-MB-231 cells. A W174A mutation that disrupts interactions between HP1(Hsalpha) and PXVXL-containing partner proteins reduced invasion similar to that of the wild type protein. In contrast, an I165E mutation that disrupts dimerization of HP1(Hsalpha) did not decrease invasion. No gross changes in localization and abundance of HP1(Hsbeta), HP1(Hsgamma), and meK9 H3 were observed upon expression of wild type and mutant forms of HP1(Hsalpha) in MDA-MB-231 cells. Taken together, these data demonstrate that modulation of HP1(Hsalpha) alters the invasive potential of breast cancer cells through mechanisms requiring HP1 dimerization, but not interactions with PXVXL-containing proteins.