Distribution and Outcomes of a Phenotype-Based Approach to Guide COPD Management: Results from the CHAIN Cohort

RationaleThe Spanish guideline for COPD (GesEPOC) recommends COPD treatment according to four clinical phenotypes: non-exacerbator phenotype with either chronic bronchitis or emphysema (NE), asthma-COPD overlap syndrome (ACOS), frequent exacerbator phenotype with emphysema (FEE) or frequent exacerbator phenotype with chronic bronchitis (FECB). However, little is known on the distribution and outcomes of the four suggested phenotypes.ObjectiveWe aimed to determine the distribution of these COPD phenotypes, and their relation with one-year clinical outcomes.MethodsWe followed a cohort of well-characterized patients with COPD up to one-year. Baseline characteristics, health status (CAT), BODE index, rate of exacerbations and mortality up to one year of follow-up were compared between the four phenotypes.ResultsOverall, 831 stable COPD patients were evaluated. They were distributed as NE, 550 (66.2%); ACOS, 125 (15.0%); FEE, 38 (4.6%); and FECB, 99 (11.9%); additionally 19 (2.3%) COPD patients with frequent exacerbations did not fulfill the criteria for neither FEE nor FECB. At baseline, there were significant differences in symptoms, FEV₁ and BODE index (all p<0.05). The FECB phenotype had the highest CAT score (17.1±8.2, p<0.05 compared to the other phenotypes). Frequent exacerbator groups (FEE and FECB) were receiving more pharmacological treatment at baseline, and also experienced more exacerbations the year after (all p<0.05) with no differences in one-year mortality. Most of NE (93%) and half of exacerbators were stable after one year.ConclusionsThere is an uneven distribution of COPD phenotypes in stable COPD patients, with significant differences in demographics, patient-centered outcomes and health care resources use.     

Proteomic analysis of human placental syncytiotrophoblast microvesicles in preeclampsia

Background

Placental syncytiotrophoblast microvesicles (STBM) are shed into the maternal circulation during normal pregnancy. STBM circulate in significantly increased amounts in preeclampsia (PE) and are considered to be among contributors to the exaggerated proinflammatory, procoagulant state of PE. However, protein composition of STBM in normal pregnancy and PE remains unknown. We therefore sought to determine the protein components of STBM and whether STBM protein expressions differ in preeclamptic and normal pregnancies.Patients with PE (n = 3) and normal pregnant controls (n = 6) were recruited. STBM were prepared from placental explant culture supernatant. STBM proteins were analyzed by a combination of 1D Gel-LC-MS/MS. Protein expressions levels were quantified using spectral counts and validated by immunohistochemistry.

Results

Over 400 proteins were identified in the STBM samples. Among these, 25 proteins were found to be differentially expressed in preeclampsia compared to healthy pregnant controls, including integrins, annexins and histones.

Conclusion

STBM proteins include those that are implicated in immune response, coagulation, oxidative stress, apoptosis as well as lipid metabolism pathways. Differential protein expressions of STBM suggest their pathophysiological relevance in PE.

Electronic supplementary material

The online version of this article (doi:10.1186/1559-0275-11-40) contains supplementary material, which is available to authorized users.     

Simultaneous assessment of autophagy and apoptosis using multispectral imaging cytometry

Multiple stress pathways result in the induction of autophagy and apoptosis. Current methods (e.g., protein gel blot, microscopy) do not offer quantitative single-cell resolution, thus making it difficult to discern if these pathways are mutually exclusive or, in some situations, cooperative in executing cell death. We report a novel method that enables high-throughput, high-content assessment of LC3 puncta and caspase-3 cleavage at the single cell level.     

State of the science in reconciling top‐down and bottom‐up approaches for terrestrial CO2 budget

Robust estimates of CO₂ budget, CO₂ exchanged between the atmosphere and terrestrial biosphere, are necessary to better understand the role of the terrestrial biosphere in mitigating anthropogenic CO₂ emissions. Over the past decade, this field of research has advanced through understanding of the differences and similarities of two fundamentally different approaches: “top‐down” atmospheric inversions and “bottom‐up” biosphere models. Since the first studies were undertaken, these approaches have shown an increasing level of agreement, but disagreements in some regions still persist, in part because they do not estimate the same quantity of atmosphere–biosphere CO₂ exchange. Here, we conducted a thorough comparison of CO₂ budgets at multiple scales and from multiple methods to assess the current state of the science in estimating CO₂ budgets. Our set of atmospheric inversions and biosphere models, which were adjusted for a consistent flux definition, showed a high level of agreement for global and hemispheric CO₂ budgets in the 2000s. Regionally, improved agreement in CO₂ budgets was notable for North America and Southeast Asia. However, large gaps between the two methods remained in East Asia and South America. In other regions, Europe, boreal Asia, Africa, South Asia, and Oceania, it was difficult to determine whether those regions act as a net sink or source because of the large spread in estimates from atmospheric inversions. These results highlight two research directions to improve the robustness of CO₂ budgets: (a) to increase representation of processes in biosphere models that could contribute to fill the budget gaps, such as forest regrowth and forest degradation; and (b) to reduce sink–source compensation between regions (dipoles) in atmospheric inversion so that their estimates become more comparable. Advancements on both research areas will increase the level of agreement between the top‐down and bottom‐up approaches and yield more robust knowledge of regional CO₂ budgets.     

Ultrastructure of multilayered cultures of human gingival epithelial cells: attachment to enamel surfaces in vitro

Human gingival cells were collected using an enzymatic procedure and seeded on a feeder layer of irradiated mouse 3T3 fibroblasts. Epithelial cells generate stratified colonies ultimately forming an epithelium which was studied using electron microscopy. When this epithelium-like structure was dispased and transferred to enamel surfaces, the relationship between basal cells and enamel corresponded to half-desmosomes and a discontinuous extracellular matrix.     

Optical immunosensor for fast and sensitive detection of DDT and related compounds in river water samples

A surface plasmon resonance (SPR) based immunosensor has been developed for the monitoring of environmentally persistent pollutants like DDT, its metabolites and analogues in real water samples. A reusable immunosurface is provided via the covalent attachment of the analyte derivative to a self-assembled alkanethiol monolayer formed onto the SPR gold-thin layer. The regeneration of the sensor surface allowed the performance of 270 assay cycles within an analysis time of 20 min for each assay cycle. Immunoassays based on a binding inhibition format were performed by using two monoclonal antibodies (MAbs) with different selectivity. Low limits of detection (LODs), in the sub-nanogram per litre range, were attained for DDT-selective (15 ng L-1) and DDT group-selective immunoassays (31 ng L-1). Both assays were carried out in spiked river water samples without significant effect of the matrix. SPR measurements were validated using gas-chromatography-mass spectrometry. The comparison between methods was in good agreement showing an excellent correlation coefficient (r2=0.995). The SPR analysis of DDT proved to be three times more sensitive than colorimetric ELISAs without the need of labelling and a much lower time of response. Our SPR biosensor portable platform (beta-SPR) is already commercialised by the company SENSIA, S.L. (Spain).     

Arsenic trioxide sensitizes promonocytic leukemia cells to TNFalpha-induced apoptosis via p38-MAPK-regulated activation of both receptor-mediated and mitochondrial pathways

Treatment with the anti-leukemic drug arsenic trioxide (As(2)O(3), 1-4 microM) sensitizes U937 promonocytes and other human myeloid leukemia cell lines (HL60, NB4) to apoptosis induction by TNFalpha. As(2)O(3) plus TNFalpha increases TNF receptor type 1 (TNF-R1) expression, decreases c-FLIP(L) expression, and causes caspase-8 and Bid activation, and apoptosis is reduced by anti-TNF-R1 neutralizing antibody and caspase-8 inhibitor. The treatment also causes Bax translocation to mitochondria, cytochrome c and Omi/HtrA2 release from mitochondria, XIAP down-regulation, and caspase-9 and caspase-3 activation. Bcl-2 over-expression inhibits cytochrome c release and apoptosis, and also prevents c-FLIP(L) down-regulation and caspase-8 activation, but not TNF-R1 over-expression. As(2)O(3) does not affect Akt phosphorylation/activation or intracellular GSH content, nor prevents the TNFalpha-provoked stimulation of p65-NF-kappaB translocation to the nucleus and the increase in NF-kappaB binding activity. Treatments with TNFalpha alone or with As(2)O(3) plus TNFalpha cause TNF-R1-mediated p38-MAPK phosphorylation/activation. P38-MAPK-specific inhibitors attenuate the As(2)O(3) plus TNFalpha-provoked activation of caspase-8/Bid, Bax translocation, cytochrome c release, and apoptosis induction. In conclusion, the sensitization by As(2)O(3) to TNFalpha-induced apoptosis in promonocytic leukemia cells is an Akt/NF-kappaB-independent, p38-MAPK-regulated process, which involves the interplay of both the receptor-mediated and mitochondrial executioner pathways.     

Solution structure of poly(ethylene) glycol-conjugated hemoglobin revealed by small-angle X-ray scattering: implications for a new oxygen therapeutic

Developing protein therapeutics has posed challenges due to short circulating times and toxicities. Recent advances using poly(ethylene) glycol (PEG) conjugation have improved their performance. A PEG-conjugated hemoglobin (Hb), Hemospan, is in clinical trials as an oxygen therapeutic. Solutions of PEG-hemoglobin with two (P5K2) or six to seven strands of 5-kD PEG (P5K6) were studied by small-angle x-ray scattering. PEGylation elongates the dimensions (Hb < P5K2 < P5K6) and leaves the tertiary hemoglobin structure unchanged but compacts its quaternary structure. The major part of the PEG chains visualized by ab initio reconstruction protrudes away from hemoglobin, whereas the rest interacts with the protein. PEGylation introduces intermolecular repulsion, increasing with conjugated PEG amount. These results demonstrate how PEG surface shielding and intermolecular repulsion may prolong intravascular retention and lack of reactivity of PEG-Hb, possibly by inhibiting binding to the macrophage CD163 hemoglobin-scavenger receptor. The proposed methodology for assessment of low-resolution structures and interactions is a powerful means for rational design of PEGylated therapeutic agents.