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Concept: Pneumonia

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Over 100 million women use progesterone therapies worldwide. Despite having immunomodulatory and repair properties, their effects on the outcome of viral diseases outside of the reproductive tract have not been evaluated. Administration of exogenous progesterone (at concentrations that mimic the luteal phase) to progesterone-depleted adult female mice conferred protection from both lethal and sublethal influenza A virus (IAV) infection. Progesterone treatment altered the inflammatory environment of the lungs, but had no effects on viral load. Progesterone treatment promoted faster recovery by increasing TGF-β, IL-6, IL-22, numbers of regulatory Th17 cells expressing CD39, and cellular proliferation, reducing protein leakage into the airway, improving pulmonary function, and upregulating the epidermal growth factor amphiregulin (AREG) in the lungs. Administration of rAREG to progesterone-depleted females promoted pulmonary repair and improved the outcome of IAV infection. Progesterone-treatment of AREG-deficient females could not restore protection, indicating that progesterone-mediated induction of AREG caused repair in the lungs and accelerated recovery from IAV infection. Repair and production of AREG by damaged respiratory epithelial cell cultures in vitro was increased by progesterone. Our results illustrate that progesterone is a critical host factor mediating production of AREG by epithelial cells and pulmonary tissue repair following infection, which has important implications for women’s health.

Concepts: Reproduction, Lung, Pneumonia, Epidermal growth factor, Epithelium, Skin, Cervix, Influenzavirus A

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Knowledge regarding whether benzodiazepines and similarly acting non-benzodiazepines (Z-drugs) are associated with an increased risk of pneumonia among older adults is lacking. We sought to investigate this association among community-dwelling adults with Alzheimer disease, a condition in which both sedative/hypnotic use and pneumonia are common.

Concepts: Alzheimer's disease, Pneumonia, Benzodiazepine, Zaleplon, Zolpidem

190

Klebsiella pneumoniae is a Gram-negative pathogen responsible for a wide range of infections, including pneumonia and bacteremia, and is rapidly acquiring antibiotic resistance. K. pneumoniae requires secretion of siderophores, low-molecular-weight, high-affinity iron chelators, for bacterial replication and full virulence. The specific combination of siderophores secreted by K. pneumoniae during infection can impact tissue localization, systemic dissemination, and host survival. However, the effect of these potent iron chelators on the host during infection is unknown. In vitro, siderophores deplete epithelial cell iron, induce cytokine secretion, and activate the master transcription factor hypoxia inducible factor-1α (HIF-1α) protein that controls vascular permeability and inflammatory gene expression. Therefore, we hypothesized that siderophore secretion by K. pneumoniae directly contributes to inflammation and bacterial dissemination during pneumonia. To examine the effects of siderophore secretion independently of bacterial growth, we performed infections with tonB mutants that persist in vivo but are deficient in siderophore import. Using a murine model of pneumonia, we found that siderophore secretion by K. pneumoniae induces the secretion of interleukin-6 (IL-6), CXCL1, and CXCL2, as well as bacterial dissemination to the spleen, compared to siderophore-negative mutants at an equivalent bacterial number. Furthermore, we determined that siderophore-secreting K. pneumoniae stabilized HIF-1α in vivo and that bacterial dissemination to the spleen required alveolar epithelial HIF-1α. Our results indicate that siderophores act directly on the host to induce inflammatory cytokines and bacterial dissemination and that HIF-1α is a susceptibility factor for bacterial invasion during pneumonia.

Concepts: Immune system, Inflammation, Gene, Gene expression, Cell, Bacteria, Microbiology, Pneumonia

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The presence of acute or chronic respiratory failure is often seen as a terminal phase of chronic obstructive pulmonary disease. A great variability in end-of-life practice is observed in these patients mainly because physicians are not always able to correctly predict survival. There is a need for a clear discussion about decision making earlier than when acute respiratory failure ensues. Indeed, a perceived poor quality of life does not necessarily correlate with a clear willingness to refuse invasive or noninvasive mechanical ventilation. It has been suggested to start palliative care earlier, together with curative and restorative care, when there is an increased intensity of symptoms. The patients eligible for palliative care are those complaining of breathlessness, pain, fatigue and depression, which in some studies accounted for a prevalence much higher than 50%. Among comfort measures for palliation, oxygen is frequently prescribed even when the criteria for long-term home oxygen therapy are not met; however, when compared with air, no benefits on dyspnoea have been found. The only drug with a proven effect on dyspnoea is morphine, but not when it is delivered with a nebuliser. Finally, noninvasive ventilation may be used only as a comfort measure for palliation to maximise comfort by minimising adverse effects.

Concepts: Pulmonology, Pneumonia, Mechanical ventilation, Palliative care, Chronic obstructive pulmonary disease, Palliative medicine, End-of-life care, Terminal sedation

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We have identified a natural clay mixture that exhibits in vitro antibacterial activity against a broad spectrum of bacterial pathogens. We collected four samples from the same source and demonstrated through antibacterial susceptibility testing that these clay mixtures have markedly different antibacterial activity against Escherichia coli and methicillin-resistant Staphylococcus aureus (MRSA). Here, we used X-ray diffraction (XRD) and inductively coupled plasma - optical emission spectroscopy (ICP-OES) and - mass spectrometry (ICP-MS) to characterize the mineralogical and chemical features of the four clay mixture samples. XRD analyses of the clay mixtures revealed minor mineralogical differences between the four samples. However, ICP analyses demonstrated that the concentrations of many elements, Fe, Co, Cu, Ni, and Zn, in particular, vary greatly across the four clay mixture leachates. Supplementation of a non-antibacterial leachate containing lower concentrations of Fe, Co, Ni, Cu, and Zn to final ion concentrations and a pH equivalent to that of the antibacterial leachate generated antibacterial activity against E. coli and MRSA, confirming the role of these ions in the antibacterial clay mixture leachates. Speciation modeling revealed increased concentrations of soluble Cu(2+) and Fe(2+) in the antibacterial leachates, compared to the non-antibacterial leachates, suggesting these ionic species specifically are modulating the antibacterial activity of the leachates. Finally, linear regression analyses comparing the log10 reduction in bacterial viability to the concentration of individual ion species revealed positive correlations with Zn(2+) and Cu(2+) and antibacterial activity, a negative correlation with Fe(3+), and no correlation with pH. Together, these analyses further indicate that the ion concentration of specific species (Fe(2+), Cu(2+), and Zn(2+)) are responsible for antibacterial activity and that killing activity is not solely attributed to pH.

Concepts: Regression analysis, Bacteria, Pneumonia, Staphylococcus aureus, Antibiotic resistance, Escherichia coli, Chemistry, Methicillin-resistant Staphylococcus aureus

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Adoption and maintenance of healthy behaviours is pivotal to chronic disease self-management as this influences disease progression and impact. This qualitative study investigated health behaviour changes adopted by participants with moderate or severe chronic obstructive pulmonary disease (COPD) recruited to a randomised controlled study of telephone-delivered health-mentoring.

Concepts: Psychology, Osteoporosis, Medicine, Asthma, Pneumonia, Chronic obstructive pulmonary disease

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Background Both targeted decolonization and universal decolonization of patients in intensive care units (ICUs) are candidate strategies to prevent health care-associated infections, particularly those caused by methicillin-resistant Staphylococcus aureus (MRSA). Methods We conducted a pragmatic, cluster-randomized trial. Hospitals were randomly assigned to one of three strategies, with all adult ICUs in a given hospital assigned to the same strategy. Group 1 implemented MRSA screening and isolation; group 2, targeted decolonization (i.e., screening, isolation, and decolonization of MRSA carriers); and group 3, universal decolonization (i.e., no screening, and decolonization of all patients). Proportional-hazards models were used to assess differences in infection reductions across the study groups, with clustering according to hospital. Results A total of 43 hospitals (including 74 ICUs and 74,256 patients during the intervention period) underwent randomization. In the intervention period versus the baseline period, modeled hazard ratios for MRSA clinical isolates were 0.92 for screening and isolation (crude rate, 3.2 vs. 3.4 isolates per 1000 days), 0.75 for targeted decolonization (3.2 vs. 4.3 isolates per 1000 days), and 0.63 for universal decolonization (2.1 vs. 3.4 isolates per 1000 days) (P=0.01 for test of all groups being equal). In the intervention versus baseline periods, hazard ratios for bloodstream infection with any pathogen in the three groups were 0.99 (crude rate, 4.1 vs. 4.2 infections per 1000 days), 0.78 (3.7 vs. 4.8 infections per 1000 days), and 0.56 (3.6 vs. 6.1 infections per 1000 days), respectively (P<0.001 for test of all groups being equal). Universal decolonization resulted in a significantly greater reduction in the rate of all bloodstream infections than either targeted decolonization or screening and isolation. One bloodstream infection was prevented per 54 patients who underwent decolonization. The reductions in rates of MRSA bloodstream infection were similar to those of all bloodstream infections, but the difference was not significant. Adverse events, which occurred in 7 patients, were mild and related to chlorhexidine. Conclusions In routine ICU practice, universal decolonization was more effective than targeted decolonization or screening and isolation in reducing rates of MRSA clinical isolates and bloodstream infection from any pathogen. (Funded by the Agency for Healthcare Research and the Centers for Disease Control and Prevention; REDUCE MRSA ClinicalTrials.gov number, NCT00980980 .).

Concepts: Immune system, Pneumonia, Staphylococcus aureus, Methicillin-resistant Staphylococcus aureus, Penicillin

171

Multilocus sequence typing (MLST) is a widely used system for typing microorganisms by sequence analysis of housekeeping genes. The main advantage of MLST in comparison to other typing techniques is the unambiguity and transferability of sequence data. However, a main disadvantage is the high cost of DNA sequencing. Here we introduce a high-throughput MLST (HiMLST) method that employs next-generation sequencing (NGS) technology (Roche 454), to generate large quantities of high-quality MLST data at low costs. The HiMLST protocol consists of two steps. In the first step MLST target genes are amplified by PCR in multi-well plates. During this PCR the amplicons of each bacterial isolate are provided with a unique DNA barcode, the multiplex identifier (MID). In the second step all amplicons are pooled and sequenced in a single NGS-run. The MLST profile of each individual isolate can be retrieved easily using its unique MID. With HiMLST we have profiled 575 isolates of Legionella pneumophila, Staphylococcus aureus, Pseudomonas aeruginosa and Streptococcus pneumoniae in mixed species HiMLST experiments. In conclusion, the introduction of HiMLST paves the way for a broad employment of the MLST as a high-quality and cost-effective method for typing microbial species.

Concepts: DNA, Bacteria, Molecular biology, Pneumonia, Species, Antibiotic resistance, Biotechnology, Microorganism

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BACKGROUND: Pulmonary Rehabilitation for moderate Chronic Obstructive Pulmonary Disease in primary care could improve patients' quality of life. METHODS: This study aimed to assess the efficacy of a 3-month Pulmonary Rehabilitation (PR) program with a further 9 months of maintenance (RHBM group) compared with both PR for 3 months without further maintenance (RHB group) and usual care in improving the quality of life of patients with moderate COPD.We conducted a parallel-group, randomized clinical trial in Majorca primary health care in which 97 patients with moderate COPD were assigned to the 3 groups. Health outcomes were quality of life, exercise capacity, pulmonary function and exacerbations. RESULTS: We found statistically and clinically significant differences in the three groups at 3 months in the emotion dimension (0.53; 95%CI0.06-1.01) in the usual care group, (0.72; 95%CI0.26-1.18) the RHB group (0.87; 95%CI 0.44-1.30) and the RHBM group as well as in fatigue (0.47; 95%CI 0.17-0.78) in the RHBM group. After 1 year, these differences favored the long-term rehabilitation group in the domains of fatigue (0.56; 95%CI 0.22-0.91), mastery (0.79; 95%CI 0.03-1.55) and emotion (0.75; 95%CI 0.17-1.33). Between-group analysis only showed statistically and clinically significant differences between the RHB group and control group in the dyspnea dimension (0.79 95%CI 0.05-1.52). No differences were found for exacerbations, pulmonary function or exercise capacity. CONCLUSIONS: We found that patients with moderate COPD and low level of impairment did not show meaningful changes in QoL, exercise tolerance, pulmonary function or exacerbation after a one-year, community based rehabilitation program. However, long-term improvements in the emotional, fatigue and mastery dimensions (within intervention groups) were identified.Trial registration: ISRCTN94514482.

Concepts: Health care, Medicine, Epidemiology, Clinical trial, Asthma, Pneumonia, Randomized controlled trial, Chronic obstructive pulmonary disease