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Asthma is one of the most common chronic health conditions experienced during pregnancy and is associated with numerous adverse maternal and perinatal outcomes.To better understand the confidence, evidence-based knowledge and guideline use among healthcare professionals around Australia commonly involved in providing antenatal care for women with asthma.An online, cross-sectional survey was developed and distributed to maternity carers (obstetricians and midwives), primary carers (general practitioners and general practice nurses) and respiratory specialists (respiratory physicians and respiratory nurses). Self-reported confidence and use of clinical guidelines were recorded. Evidence-based knowledge was assessed with 13 questions relating to four clinical scenarios that covered recommendations from national and international guidelines.Primary carers and respiratory specialists were more confident in providing antenatal asthma care, more likely to use clinical guidelines and scored significantly higher in evidence-based knowledge of antenatal asthma management than maternity carers (P 0.01 and P 0.001, respectively). There was no significant difference in evidence-based knowledge among healthcare professionals from metropolitan, regional and rural backgrounds. However, healthcare professionals who used clinical guidelines scored significantly higher than those who did not (P 0.0001).Greater utilisation of clinical guidelines could improve the evidence-based knowledge of maternity carers. However, the absence of antenatal asthma management in obstetric- and maternity-specific guidelines poses a potential barrier that needs to be addressed. Furthermore, the development of multidisciplinary antenatal clinics, staffed by respiratory nurses and/or physicians, could improve outcomes for pregnant women with asthma who are not undertaking shared care.

Discontinuation of, and non-adherence to, inhaled corticosteroids (ICS) for asthma treatment is a significant issue in pregnancy. This study characterised beliefs about medicines in pregnant women with asthma and investigated associations with ICS adherence.Pregnant women with relatively mild asthma (n = 302) were grouped according to ICS use and self-reported adherence (≥80% doses taken). They completed questions about dislike of asthma medications and the validated Beliefs about Medicines Questionnaire (BMQ), which consists of ten questions about asthma medicines ("necessity" questions about maintaining health, or "concern" questions about adverse effects), and eight general medicine questions, scored on five-point Likert scales. The Necessity Concerns differential (N-C) was calculated, with positive scores indicating that the patient perceives the benefits of medicines to outweigh the risks.ICS was used by 87 (29%) women, with 49 (56%) self-reporting adherence. Of the 22% who disliked taking asthma medications during pregnancy, 20% had the belief that the medication was unsafe. ICS users had a significantly higher BMQ necessity score and higher necessity-concern differential score than non-users; when adjusted for covariates, ICS non-adherence was associated with a lower necessity score (p = 0.015). Women adherent to ICS were more likely to agree to "my health at present depends on my asthma medication" compared to non-adherent ICS users.ICS non-adherence was not associated with having relatively more concerns about asthma medicines; however, ICS users were more likely to perceive that the benefits of medication use outweighed any risks. Interventions to improve asthma medication adherence in pregnancy are needed.

Asthma is a common condition in preganncy and associated with perinatal complications and respiratory illness in offspring. This secondary analysis of an RCT investigated the influence of maternal body mass index (BMI) and gestational weight gain (GWG) and fractional exhaled nitric oxide (FeNO)-based management, on asthma exacerbations in pregnancy and wheeze-related outcomes in offspring. Women were randomised prior to 22 weeks gestation to asthma treatment adjustment according to symptoms (control group) or FeNO and symptoms (FeNO group). Exacerbations requiring medical intervention were recorded prospectively. Height and weight were measured at baseline, and in late pregnancy for a sub-group of women. Wheeze in infancy was determined by parent report. The incidence rate ratio (IRR) for maternal exacerbations was different between management groups for non-obese mothers (0.42, 95%CI 0.33-0.76, p=0.004, n=129) and women with GWG within recommendations (0.28, 95%CI 0.10-0.75, P=0.012, n=43), but not for obese mothers (0.59, 95%CI 0.32-1.09, P=0.09, n=88), or women with excess GWG (0.58, 95%CI 0.32-1.04, P=0.07, n=104). Recurrent bronchiolitis occurred in 5.3% of infants born to non-overweight mothers, 16.7% of infants of overweight mothers and 21.7% of infants of obese mothers in the control group. In the FeNO group, only 2 infants of obese mothers had recurrent bronchiolitis (7.1%, P=0.031). FeNO-based management reduces exacerbations in pregnancy and infant bronchiolitis, but these effects are attenuated among obese mothers and those with excess GWG, indicating the importance of weight management in contributing to improved asthma management in pregnancy.

Background and objective Neutrophil extracellular traps (NETs) are web-like structures comprising DNA and antimicrobial proteins, expelled from neutrophils during NETosis. Persistence of NETs can be pro-inflammatory, yet their role in respiratory disease remains unclear. This study aimed to investigate the presence of NETs in sputum from patients with asthma and COPD, and the relationship of NETs with inflammatory phenotype and disease severity. Methods Induced sputum was collected from healthy controls, asthma and COPD patients. Extracellular DNA (eDNA) was quantified by PicoGreen. LL-37, α-defensins1–3, NE, IL-1β and CXCL8 were quantified by ELISA. PAD4 and NLRP3 gene expression was performed using qPCR. NETs were imaged in sputum smears using immunofluorescence microscopy. Results Sputum eDNA and NET neutrophil antimicrobial proteins were significantly elevated in asthma and COPD compared with healthy controls. Levels of eDNA and NET components were significantly higher in neutrophilic versus non-neutrophilic asthma and COPD. NETs were clearly visualized in sputum smears. PAD4 mRNA was upregulated in neutrophilic COPD. The level of eDNA was higher in severe asthma. High eDNA levels were associated with heightened innate immune responses, including elevated CXCL8 and IL-1β, and NLRP3 gene expression in both COPD and asthma. Antimicrobial proteins and eDNA were positively correlated with airway neutrophils, and negatively correlated with lung function and symptoms. Conclusion NETs are present in the airways of subjects with asthma and COPD. Accumulation of excessive NETs was associated with activation of innate immune responses contributing to disease pathogenesis in chronic airway disease.

Viruses manipulate the complex interferon and interferon-stimulated gene (ISG) system in different ways. We have previously shown that HIV inhibits type I and III interferons in its key target cells but directly stimulates a subset of >20 ISGs in macrophages and dendritic cells, many of which are antiviral. Here, we examine the mechanism of induction of ISGs and show this occurs in two phases. The first phase was transient (0 to 24 h postinfection [hpi]), induced mainly by extracellular vesicles and one of its component proteins, HSP90α, contained within the HIV inoculum. The second, dominant, and persistent phase (>48 hpi) was induced via newly transcribed HIV RNA and sensed via RIGI, as shown by the reduction in ISG expression after the knockdown of the RIGI adaptor, MAVS, by small interfering RNA (siRNA) and the inhibition of both the initiation and elongation of HIV transcription by short hairpin RNA (shRNA) transcriptional silencing. We further define the induction pathway, showing sequential HIV RNA stimulation via Tat, RIGI, MAVS, IRF1, and IRF7, also identified by siRNA knockdown. IRF1 also plays a key role in the first phase. We also show that the ISGs IFIT1 to -3 inhibit HIV production, measured as extracellular infectious virus. All induced antiviral ISGs probably lead to restriction of HIV replication in macrophages, contributing to a persistent, noncytopathic infection, while the inhibition of interferon facilitates spread to adjacent cells. Both may influence the size of macrophage HIV reservoirs in vivo . Elucidating the mechanisms of ISG induction may help in devising immunotherapeutic strategies to limit the size of these reservoirs. IMPORTANCE HIV, like other viruses, manipulates the antiviral interferon and interferon-stimulated gene (ISG) system to facilitate its initial infection and establishment of viral reservoirs. HIV specifically inhibits all type I and III interferons in its target cells, including macrophages, dendritic cells, and T cells. It also induces a subset of over 20 ISGs of differing compositions in each cell target. This occurs in two temporal phases in macrophages. Extracellular vesicles contained within the inoculum induce the first, transient phase of ISGs. Newly transcribed HIV RNA induce the second, dominant ISG phase, and here, the full induction pathway is defined. Therefore, HIV nucleic acids, which are potent inducers of interferon and ISGs, are initially concealed, and antiviral ISGs are not fully induced until replication is well established. These antiviral ISGs may contribute to persistent infection in macrophages and to the establishment of viral reservoirs in vivo .

Background Maternal asthma is associated with perinatal complications and respiratory illness in offspring. Obesity increases asthma exacerbation risk in pregnancy and risk of wheeze in offspring. Objectives In this secondary analysis of a randomized controlled trial, we investigated the influence of maternal body mass index, gestational weight gain (GWG), and fractional exhaled nitric oxide (FENO)-based management on asthma exacerbations in pregnancy and offspring wheeze. Methods A total of 220 women were randomized to asthma treatment adjustment according to symptoms (control group), or FENO and symptoms (FENO group). Exacerbations were recorded prospectively. Height and weight were measured at baseline, and in late pregnancy. GWG was categorized according to Institute of Medicine guidelines. A validated parent-completed questionnaire assessed infant wheeze-related outcomes. Results FENO-based management was associated with a significantly lower incidence rate ratio for maternal exacerbations in nonobese mothers (0.52, 95% confidence interval [CI], 0.31-0.88, P = .015, n = 129), and women with GWG within recommendations (0.35, 95% CI, 0.12-0.96, P = .042, n = 43), but not for obese mothers (0.59, 95% CI, 0.32-1.08, P = .089, n = 88), or women with excess GWG (0.58, 95% CI, 0.32-1.04, P = .07, n = 104). Recurrent bronchiolitis occurred in 5.3% (n = 1) of infants born to non-overweight mothers, 16.7% (n = 3) of infants of overweight mothers, and 21.7% (n = 5) of infants of obese mothers in the control group. In the FENO group, 2 infants of obese mothers had recurrent bronchiolitis (7.1%, P = .031). Conclusions The benefits of FENO-based management are attenuated among obese mothers and those with excess GWG, indicating the importance of weight management in contributing to improved asthma management in pregnancy.

Macrophages are key target cells for HIV-1. HIV-1BaL induced a subset of interferon-stimulated genes in monocyte-derived macrophages (MDMs), which differed from that in monocyte-derived dendritic cells and CD4 T cells, without inducing any interferons. Inhibition of type I interferon induction was mediated by HIV-1 inhibition of interferon-regulated factor (IRF3) nuclear translocation. In MDMs, viperin was the most up-regulated interferon-stimulated genes, and it significantly inhibited HIV-1 production. HIV-1 infection disrupted lipid rafts via viperin induction and redistributed viperin to CD81 compartments, the site of HIV-1 egress by budding in MDMs. Exogenous farnesol, which enhances membrane protein prenylation, reversed viperin-mediated inhibition of HIV-1 production. Mutagenesis analysis in transfected cell lines showed that the internal S-adenosyl methionine domains of viperin were essential for its antiviral activity. Thus viperin may contribute to persistent noncytopathic HIV-1 infection of macrophages and possibly to biologic differences with HIV-1–infected T cells.

Neutrophil extracellular traps (NETs) are web-like structures comprising DNA and antimicrobial proteins, expelled from neutrophils during NETosis. Persistence of NETs can be pro-inflammatory, yet their role in respiratory disease remains unclear. This study aimed to investigate the presence of NETs in sputum from patients with asthma and COPD, and the relationship of NETs with inflammatory phenotype and disease severity.Induced sputum was collected from healthy controls, asthma and COPD patients. Extracellular DNA (eDNA) was quantified by PicoGreen. LL-37, α-defensins1-3, NE, IL-1β and CXCL8 were quantified by ELISA. PAD4 and NLRP3 gene expression was performed using qPCR. NETs were imaged in sputum smears using immunofluorescence microscopy.Sputum eDNA and NET neutrophil antimicrobial proteins were significantly elevated in asthma and COPD compared with healthy controls. Levels of eDNA and NET components were significantly higher in neutrophilic versus non-neutrophilic asthma and COPD. NETs were clearly visualized in sputum smears. PAD4 mRNA was upregulated in neutrophilic COPD. The level of eDNA was higher in severe asthma. High eDNA levels were associated with heightened innate immune responses, including elevated CXCL8 and IL-1β, and NLRP3 gene expression in both COPD and asthma. Antimicrobial proteins and eDNA were positively correlated with airway neutrophils, and negatively correlated with lung function and symptoms.NETs are present in the airways of subjects with asthma and COPD. Accumulation of excessive NETs was associated with activation of innate immune responses contributing to disease pathogenesis in chronic airway disease.