Background
While the clinical characteristics and outcomes of asthma‐chronic obstructive pulmonary disease (COPD) overlap (ACO) have been frequently compared with those of COPD or asthma, the ...prevalence and features of ACO in patients with severe asthma are unclear.
Objectives
Evaluation of the prevalence and clinical features of ACO using the Korean severe asthma registry.
Methods
At the time of registration, ACO was determined in patients with severe asthma by attending specialists. Patients were classified into ACO and non‐ACO groups, and the demographic and clinical characteristics of these two groups were compared.
Results
Of 482 patients with severe asthma, 23.7% had ACO. Patients in the ACO group were more likely to be male (P < .001), older (P < .001), and ex‐ or current smokers (P < .001) compared with those in the non‐ACO group. Patients in the ACO group had lower mean forced expiratory volume in 1 second (P < .001) and blood eosinophil percentage (P = .006), but higher blood neutrophil percentage (P = .027) than those in the non‐ACO group. The ACO group used more inhaled long‐acting muscarinic antagonist (P < .001), methylxanthine (P = .001), or sustained systemic corticosteroid (P = .002). In addition, unscheduled emergency department visits due to exacerbation were more frequent in the ACO group (P = .006).
Conclusion
Among patients with severe asthma, those with ACO were older, predominantly male, and were more likely to have a smoking history than those with asthma only. Patients with ACO used more systemic corticosteroid and had more frequent exacerbations related to emergency department visits than those with severe asthma only.
We found that about one‐fourth of patients with severe asthma was diagnosed with ACO by specialists. The most common reason for ACO diagnosis was smoking history. ACO patients were predominantly male, older, and had more smoking history compared with non‐ACO patients. ACO patients had higher blood neutrophil count, but lower lung function. ACO patients used more LAMA, methylxanthine, and systemic corticosteroid and had more frequent exacerbations related to ER visits compared with those with severe asthma only. Abbreviations: ACO, asthma‐COPD overlap; ER, emergency room; FEV1, forced expiratory volume in one second.
Abstract
Using our ingeniously designed new filter systems, we investigate multiple stellar populations of the red giant branch (RGB) and the asymptotic giant branch (AGB) in the globular cluster ...(GC) M5. Our results are the following. (1) Our
index accurately traces nitrogen abundances in M5, while other color indices fail to do so. (2) We find bimodal CN distributions in both RGB and AGB sequences, with number ratios between CN-weak (CN-w) and CN-strong (CN-s) of
n
(CN-w):
n
(CN-s) = 29:71 (±2) and 21:79 (±7), respectively. (3) We also find a bimodal photometric N/Fe distribution for M5 RGB stars. (4) Our
–O/Fe and
–Na/Fe relations show clear discontinuities between the two RGB populations. (5) Although small, the RGB bump of CN-s is slightly brighter,
= 0.07 ± 0.04 mag. If real, the difference in the helium abundance becomes
= 0.028 ± 0.016, in the sense that CN-s is more helium enhanced. (6) Very similar radial but different spatial distributions with comparable center positions are found for the two RGB populations. The CN-s RGB and AGB stars are more elongated along the NW–SE direction. (7) The CN-s population shows a substantial net projected rotation, while that of the CN-w population is nil. (8) Our results confirm the deficiency of CN-w AGB stars previously noted by others. We show that it is most likely due to stochastic truncation in the outer part of the cluster. Finally, we discuss the formation scenario of M5.
Several experimental studies have provided evidence that bone‐marrow derived mesenchymal stem (stromal) cells (MSC) may be effective in treating critically ill surgical patients who develop traumatic ...brain injury, acute renal failure, or the acute respiratory distress syndrome. There is also preclinical evidence that MSC may be effective in treating sepsis‐induced organ failure, including evidence that MSC have antimicrobial properties. This review considers preclinical studies with direct relevance to organ failure following trauma, sepsis or major infections that apply to critically ill patients. Progress has been made in understanding the mechanisms of benefit, including MSC release of paracrine factors, transfer of mitochondria, and elaboration of exosomes and microvesicles. Regardless of how well they are designed, preclinical studies have limitations in modeling the complexity of clinical syndromes, especially in patients who are critically ill. In order to facilitate translation of the preclinical studies of MSC to critically ill patients, there will need to be more standardization regarding MSC production with a focus on culture methods and cell characterization. Finally, well designed clinical trials will be needed in critically ill patient to assess safety and efficacy. Stem Cells 2017;35:316–324
Abstract
We present a multiple stellar population study of the globular cluster NGC 6752. We show that our new photometric CN index accurately traces the CN and the nitrogen abundances in cool ...giants, finding the discrete double red giant branch (RGB) and asymptotic giant branch (AGB) sequences with number ratios between the CN-weak and the CN-strong populations of
n
(CN-w):
n
(CN-s) = 25:75 (±3; RGB) and 79:21 (±13; AGB). The discrepancy in these number ratios suggests that a significant fraction of the low-mass CN-s stars failed to evolve into the AGB phase. However, unlike previous studies, our results indicate the presence of an extreme CN-s AGB population in NGC 6752, which may require follow-up spectroscopic study. Similar to what is seen for M5, the evolution of the nitrogen abundance is discrete and discontinuous, while the evolutions of oxygen and sodium are continuous between the two populations in NGC 6752, implying that different astrophysical sources are responsible for the evolutions of these elements. In addition, the helium abundance inferred from the RGB bump magnitude shows that the CN-s population is slightly more helium-enhanced. Despite the identical cumulative radial distributions between the two populations, the structure-kinematics coupling can be observed in individual populations: the CN-w population has a spatially elongated shape with a faster rotation, while the CN-s population shows weak or no net rotation, with a spatially symmetric shape, raising important questions about the long-term dynamical evolution of the GCs.
Abstract
We perform a comparative study of the ex situ second-parameter pair globular clusters (GCs) M30 and M92, having similar metallicities but different horizontal branch morphologies. We obtain ...similar mean primordial carbon abundances for both clusters. However, M92 shows a large dispersion in carbon due to a more extended C–N anticorrelation, while M30 exhibits a higher primordial nitrogen abundance, suggesting that they have different chemical enrichment histories. Our new results confirm our previous result that M92 is a metal-complex GC showing a bimodal metallicity distribution. We also find that the metal-rich group of stars in M92 shows a helium enhancement as large as Δ
Y
∼ 0.05 from the red giant branch bump
V
magnitudes, which can also be supported by (i) a lack of bright red giant branch stars, (ii) synthetic evolutionary horizontal branch population models and (iii) the more extended spatial distribution due to different degree of the diffusion process from their lower masses. We reinterpret the Eu/Fe measurements by others, finding that the two metallicity groups of stars in M92 have significantly different Eu/Fe abundances with small scatters. This strongly suggests that they formed independently out of well-mixed interstellar media in different environments. We suggest that M92 is a more complex system than a normal GC, most likely a merger remnant of two GCs or an even more complex system. In the Appendix, we address the problems with the recently developed color–temperature relations and the usage of broadband photometry in the populational taggings.
Abstract
We present new large field-of-view (∼1°×1°) Ca-CN photometry of the prototypical metal-rich globular cluster 47 Tucanae (NGC 104). Our results are the following. (1) The populational number ...ratios of the red giant branch (RGB) and red horizontal branch (RHB) are in excellent agreement:
n
(CN-w):
n
(CN-s) = 30:70 (±1–2), where the CN-w and CN-s stand for the CN-weak and CN-strong populations, respectively. Both the CN-s RGB and RHB populations are more centrally concentrated than those of CN-w populations are. (2) Our photometric metallicities of individual RGB stars in each population can be well described by bimodal distributions with two metallicity peaks, Fe/H ∼−0.72 and −0.92 dex, where the metal-poor components occupy ∼13% of the total RGB stars. The metal-poor populations are more significantly centrally concentrated than the metal-rich populations, showing a similar result that we found in M3. (3) The RGB bump
V
magnitudes of individual populations indicate that there is no difference in the helium abundance between the two metal-poor populations, while the helium enhancement of Δ
Y
∼0.02–0.03 is required between the the two metal-rich populations. (4) The RHB morphology of 47 Tuc appears to support our idea of the bimodal metallicity distribution of the cluster. We suggest that 47 Tuc could be another example of merger remnants of two globular clusters, similar to M3 and M22.
Acute respiratory distress syndrome is a major cause of respiratory failure in critically ill patients. Despite extensive research into its pathophysiology, mortality remains high. No effective ...pharmacotherapy exists. Based largely on numerous preclinical animal studies, administration of mesenchymal stem or stromal cell (MSC) as a therapeutic for acute lung injury (ALI) holds great promise, and Phase I and II clinical trials are currently under way internationally. However, concern for the use of stem cells, specifically the risk of iatrogenic tumor formation, as well as the prohibitive cost of production, storage, and distribution of cells in bone marrow transplant facilities, may limit access to this lifesaving therapy. Accumulating evidence now suggest that novel stem cell–derived therapies, including MSC‐conditioned medium and extracellular vesicles (EVs) released from MSCs, might constitute compelling alternatives. The current review summarizes the preclinical studies testing MSC EVs as treatment for ALI and other inflammatory lung diseases. While certain logistic obstacles limit the clinical applications of MSC‐conditioned medium such as the volume required for treatment and lack of standardization of what constitutes the components of conditioned medium, the therapeutic application of MSC EVs remains promising, primarily due to ability of EVs to maintain the functional phenotype of the parent cell. However, utilization of MSC EVs will require large‐scale production and standardization concerning identification, characterization, and quantification.
Abstract
Apparently similar but multifaceted photometric systems are currently being used to investigate the multiple stellar populations in globular clusters (GCs), without the concrete general ...agreement on the definition of the multiple populations. In recent years, an attractive idea of utilization of the widely used
UBI
photometry,
C
UBI
, for the populational tagging of the giant stars in GCs has emerged. We perform a critical analysis of the
and
C
UBI
indices, finding that the populational tagging from the
C
UBI
index may not be reliable, due to the inherited trait of the broadband photometry. As a consequence, the populational number ratios and the cumulative radial distributions from the
C
UBI
index can be easily in error. The results for M3, which shows a very strong radial gradient in the populational number ratio, highlight the strengths of our
index: both the
Hubble Space Telescope
imaging and the ground-based spectroscopy failed to grasp the correct picture, which can be easily achieved with our
index with small-aperture ground-based telescopes, due to the small field of view or crowdedness in the central part of the cluster.
Abstract
We present a multiple stellar population study of the metal-poor globular cluster (GC) M92 (NGC 6341), which is long known for the substantial metallicity dispersion, using our own ...photometric system. We find two groups with slightly different mean metallicities, the metal-poor (MP) stars with Fe/H
hk
= −2.412 ± 0.03 and the metal-rich (MR) ones with −2.282 ± 0.002. The MP constitutes about 23% of the total mass with a more central concentration. Our populational tagging based on the C/Fe
ch
and N/Fe
nh
provides the mean
n
(P):
n
(I):
n
(E) = 32.2:31.6:36.2 (±2.4), where P, I, and E denote the primordial, intermediate, and extreme populations, respectively. Our populational number ratio is consistent with those of others. However, the MP has a significantly different populational number ratio than the mean value, and the domination of the primordial population in the MP is consistent with observations of Galactic GCs that less massive GCs contain larger fractions of the primordial population. Structural and constituent differences between the MP and MR may indicate that M92 is a merger remnant in a dwarf galaxy environment, consistent with recent suggestions that M92 is a GC in a dwarf galaxy or a remnant nucleus of the progenitor galaxy. Discrepancy between our method and those widely used for the Hubble Space Telescope photometry exists in the primordial population. Significant magnesium and oxygen depletions of −0.8 and −0.3 dex, respectively, and helium enhancement of Δ
Y
≳ 0.03 are required to explain the presence of this abnormal primordial group. No clear explanation is available with limited information of detailed elemental abundances.
Recent in vivo studies indicate that mesenchymal stem cells (MSCs) may have beneficial effects in the treatment of sepsis induced by bacterial infection. Administration of MSCs in these studies ...improved survival and enhanced bacterial clearance. The primary objective of this study was to test the hypothesis that human MSCs possessed intrinsic antimicrobial properties. We studied the effect of human MSCs derived from bone marrow on the bacterial growth of Gram‐negative (Escherichia coli and Pseudomonas aeruginosa) and Gram‐positive (Staphylococcus aureus) bacteria. MSCs as well as their conditioned medium (CM) demonstrated marked inhibition of bacterial growth in comparison with control medium or normal human lung fibroblasts (NHLF). Analysis of expression of major antimicrobial peptides indicated that one of the factors responsible for the antimicrobial activity of MSC CM against Gram‐negative bacteria was the human cathelicidin antimicrobial peptide, hCAP‐18/LL‐37. Both m‐RNA and protein expression data showed that the expression of LL‐37 in MSCs increased after bacterial challenge. Using an in vivo mouse model of E. coli pneumonia, intratracheal administration of MSCs reduced bacterial growth (in colony‐forming unit) in the lung homogenates and in the bronchoalveolar lavage (BAL) fluid, and administration of MSCs simultaneously with a neutralizing antibody to LL‐37 resulted in a decrease in bacterial clearance. In addition, the BAL itself from MSC‐treated mice had a greater antimicrobial activity in comparison with the BAL of phosphate buffered saline (PBS)‐treated mice. Human bone marrow‐derived MSCs possess direct antimicrobial activity, which is mediated in part by the secretion of human cathelicidin hCAP‐18/ LL‐37. STEM CELLS 2010;28:2229–2238
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