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The effects of sildenafil on ciliary beat frequency in patients with pulmonary non-tuberculous mycobacteria disease: phase I/II trial.
RATIONALE:Pulmonary non-tuberculous mycobacterial (PNTM) disease has increased over the past several decades, especially in older women. Abnormal mucociliary clearance and abnormal nasal nitric oxide (nNO) have been associated with PNTM disease in other patient cohorts. Mucociliary clearance can be affected by NO-cyclic guanosine monophosphate signalling and, therefore, modulation of the pathway may be possible with phosphodiesterase inhibitors such as sildenafil as a novel therapeutic approach. OBJECTIVE:To define ex vivo characteristics of PNTM disease affected by sildenafil. METHODS:Subjects with PNTM infections were recruited into an open-label dose-escalation trial of sildenafil. Laboratory measurements and mucociliary measurements-ciliary beat frequency, nNO and 24-hour sputum production-were collected throughout the study period. Patients received sildenafil daily during the study period, with escalation from 20 to 40 mg three times per day. MEASUREMENTS AND MAIN RESULTS:Increased ciliary beat frequency occurred after a single dose of 40 mg sildenafil and after extended dosing of 40 mg sildenafil. The increase ciliary beat frequency was not seen with 20 mg sildenafil dosing. There were no changes in sputum production, nNO production, Quality of Life-Bronchiectasis-NTM module (QOL-B-NTM) questionnaire or the St George's Respiratory Questionnaire during the study period. CONCLUSION:Sildenafil, 40 mg, increased ciliary beat frequency acutely as well as with extended administration
Discrete Particle Swarm Optimization for the minimum labelling Steiner tree problem
Particle Swarm Optimization is an evolutionary method inspired by the
social behaviour of individuals inside swarms in nature. Solutions of the problem are
modelled as members of the swarm which fly in the solution space. The evolution is
obtained from the continuous movement of the particles that constitute the swarm
submitted to the effect of the inertia and the attraction of the members who lead the
swarm. This work focuses on a recent Discrete Particle Swarm Optimization for combinatorial optimization, called Jumping Particle Swarm Optimization. Its effectiveness is
illustrated on the minimum labelling Steiner tree problem: given an undirected labelled
connected graph, the aim is to find a spanning tree covering a given subset of nodes,
whose edges have the smallest number of distinct labels
Eccentric lamellar keratolimbal grafts harvested with a manually guided microkeratome
Background: To perform lamellar keratolimbal allograft transplantation in a one- step procedure with a single graft, we investigated the feasibility of harvesting eccentric lamellar keratolimbal grafts from conventionally processed corneoscleral buttons using a manually guided microkeratome in conjunction with an artificial anterior chamber system. Methods: We used the Moria LSK- One microkeratome and the automated lamellar therapeutic keratoplasty ( ALTK) system ( Antony, France). Ten human donor eyes were used to obtain single- piece lamellar keratolimbal grafts. Specimens were processed for light and electron microscopy. Results: Eccentric keratolimbal grafts could be obtained from all human donor buttons. Grafts include a crescent- shaped limbal and a large corneal portion. No visible damage to the limbal region was discernible. Conclusion: Our data show that the LSK- One microkeratome in conjunction with the ALTK system allows harvesting eccentric keratolimbal grafts from donor corneoscleral buttons. Copyright (c) 2007 S. Karger AG, Basel
Lipstick and Logarithms: Gender, Institutional Context, and Representative Bureaucracy
According to the theory of representative bureaucracy, passive representation among public employees will lead to active representation in bureaucratic outputs. Existing research demonstrates that the link between passive and active representation exists for race but not for sex. Past research on this topic has not, however, taken into account the contextual environment that affects whether sex will translate into gender and lead to active representation in the bureaucracy. In this paper, we create a framework that specifies the conditions that affect whether passive representation results in active representation for sex and then test this framework using the case of education. We find that passive representation of women in education leads to active representation and that the institutional context affects the extent to which this link between passive and active representation occurs
Fecal biomarkers of environmental enteric dysfunction and the gut microbiota of rural Malawian children: An observational study
Environmental enteric dysfunction (EED) is a subclinical condition of the gut characterized by changes in morphology and function with underlying chronic inflammatory responses. This study characterized composition and diversity of the gut microbiota in rural Malawian children with and without signs of EED. Fecal samples were collected from children aged 1-59 months. Neopterin, myeloperoxidase and alpha-1 antitrypsin concentrations were quantified by ELISA and combined to form a composite EED score using principal component analysis. DNA was extracted from fecal samples and V4-16S rRNA gene sequencing was used to characterize the gut microbiota. The concentrations of all three biomarkers decreased with increasing age, which is consistent with other studies of children living in similar low-income settings. Firmicutes, Bacteroidetes, Proteobacteria and Actinobacteria were the dominant phyla while Faecalibacterium and Bifidobacterium were the most prevalent genera. Increased alpha diversity was associated with a reduction in neopterin concentration. Microbiota composition was different between fecal samples with low and high composite EED scores; increased abundance of Succinivibrio was associated with reduced composite EED scores
Who Commits to the Rule of Law? Constrained Government and Foreign Direct Investment in Postcommunist States
Research linking credible commitments to the rule of law in terms of property rights and contract enforcement is a hallmark of recent efforts to explain economic growth and development. However, many postcommunist states have had difficulty making such commitments and spurring growth. Many argue political polarization prevents states from reforming laws and protecting property rights in some countries whereas single-party governance renders state promises incredible in others. I analyze pooled cross-sectional time-series data for twenty-four postcommunist countries and provide evidence effective constraints among elected officials act as democratic commitment mechanisms rendering government policies credible
Treatment outcome definitions in nontuberculous mycobacterial pulmonary disease: an NTM-NET consensus statement
Nontuberculous mycobacterial pulmonary diseases (NTM-PD) are increasingly recognised as opportunistic infections of humans. These chronic pulmonary infections have two main presentations. The first is a fibro-cavitary disease, that occurs in patients with pre-existing pulmonary diseases, such as chronic obstructive pulmonary disease, bronchiectasis, previous tuberculosis or other structural lung disease. The second presentation is a nodular- bronchiectatic disease of primarily the lingula and middle lobe that tends to affect a middle- aged and elderly female population [1]. Treatment of NTM-PD requires long-term administration of complex multidrug therapies that are species-specific. Currently recommended regimens are supported by a very limited evidence base [2, 3]. The increasing incidence of NTM-PD has sparked increased interest in performing prospective randomised clinical trials [4]. One of the drawbacks of the existing case series and clinical trials is that they have applied different outcome measures [5]. This hampers meta-analyses, which are important in these still understudied infectious diseases. To enhance the quality and interpretability of the results of future trials and retrospective cohort studies, we aimed to formulate clear and broadly acceptable outcome definitions for NTM-PD treatment
Dioctahedral mixed K-Na-micas and paragonite in diagenetic to low-temperature metamorphic terrains: bulk rock chemical, thermodynamic and textural constraints
Abstract
Metamorphic mineral assemblages in low-temperature metaclastic rocks often contain paragonite and/or its precursor metastable phase (mixed K-Na-white mica). Relationships between the bulk rock major element chemistries and the formation of paragonite at seven localities from Central and SE-Europe were studied, comparing the bulk chemical characteristics with mineral assemblage, mineral chemical and metamorphic petrological data. Considerable overlaps between the projection fields of bulk chemistries of the Pg-free and Pg-bearing metaclastic rocks indicate significant differences between the actual (as analyzed) and effective bulk chemical compositions. Where inherited, clastic, inert phases/constituents were excluded, it was found that a decrease in Na/(Na+Al*) and in K/(K+Al*) ratios of rocks favors the formation and occurrence of Pg and its precursor phases (Al* denotes here the atomic quantity of aluminum in feldspars, white micas and “pure” hydrous or anhydrous aluminosilicates). In contrast to earlier suggestions, enrichment in Na and/or an increase in Na/K ratio by themselves do not lead to formation of paragonite. Bulk rock chemistries favorable to formation of paragonite and its precursor phases are characterized by enrichment in Al and depletion in Na, K, Ca (and also, Mg and Fe2+). Such bulk rock chemistries are characteristic of chemically “mature” (strongly weathered) source rocks of the pelites and may also be formed by synand post-sedimentary magmatism-related hydrothermal (leaching) activity. What part of the whole rock is active in determining the effective bulk chemistry was investigated by textural examination of diagenetic and anchizone-grade samples. It is hypothesized that although solid phases act as local sources and sinks, transport of elements such as Na through the grain boundaries have much larger communication distances. Sodium-rich white micas nucleate heterogeneously using existing phyllosilicates as templates and are distributed widely on the thin section scale. The results of modeling by THERMOCALC suggest that paragonite preferably forms at higher pressures in low-T metapelites. The stability fields of Pg-bearing assemblages increase, the Pg-in reaction line is shifted towards lower pressures, while the stability field of the Chl-Ms-Ab-Qtz assemblage decreases and is shifted towards higher temperatures with increasing Al* content and decreasing Na/(Na+Al*) and K/(K+Al*) ratios
Nontuberculous Mycobacteria–associated Lung Disease in Hospitalized Persons, United States, 1998–2005
This bacterium is an underappreciated cause of lung disease and infection rates appear to be increasing
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