The surfactant protein type B (SPB) gene, mRNA and protein.

<p>The human SPB is encoded by 11 exons on chromosome 2. The SPB RNA of approximately 2 kb encodes a preprotein of 381 amino acids. Processing of the precursor includes removal of a signal peptide of approximately 23 residues, and glycosilatyion at amino acids 129 to 131 and 311 to 313. These events occur within the endoplasmic reticulum. Sequential proteolytic cleavages by proteases ultimately yield the 8 kDa 79 amino acid active mature SPB, which is encoded in exons 6 and 7. These sequential cleavage occurs in the medial and trans/post Golgi, and finally in the multivescicular body. Mature SPB sequence contains 52% hydrophobic amino acids, 8 conserved positively-charges residues and 1 conserved negatively-charged residue. The primary structure also includes 7 cysteines, six of which are involved in the formation of the three intra-molecular disulphide bridges, while the seventh cysteine is involved in an intermolecular disulphide responsible for the dimerization of the protein.</p

Pulmonary function, cardiopulmonary exercise (CPET), and laboratory data in the two study groups.

<p>Pulmonary function, cardiopulmonary exercise (CPET), and laboratory data in the two study groups.</p

Representative image for immature surfactant protein type B (SPB) immunoblotting of plasma samples derived from the control group and HF patients grouped according New York Heart Association (NYHA) class.

<p>Representative image for immature surfactant protein type B (SPB) immunoblotting of plasma samples derived from the control group and HF patients grouped according New York Heart Association (NYHA) class.</p

Relationship between surfactant proteins and RAGE levels and general, clinical, pulmonary function and cardiopulmonary exercise data in the heart failure population.

<p>SPs, RAGE, Peak VO₂, VE/VCO₂ slope and BNP levels are transformed into natural logarithm. BMI: body mass index. For all abbreviations see <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0115030#pone-0115030-t001" target="_blank">table 1</a> and <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0115030#pone-0115030-t002" target="_blank">table 2</a>.</p><p>Relationship between surfactant proteins and RAGE levels and general, clinical, pulmonary function and cardiopulmonary exercise data in the heart failure population.</p

Relationship between surfactant proteins and RAGE levels in the heart failure population.

<p>SPs and RAGE levels are transformed into natural logarithm. For abbreviation see <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0115030#pone-0115030-t001" target="_blank">table 1</a> and <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0115030#pone-0115030-t002" target="_blank">2</a>.</p><p>Relationship between surfactant proteins and RAGE levels in the heart failure population.</p

Relationship between each of the five studied serum biomarkers and lung diffusing capacity values in the heart failure population.

<p>Immature SP-B levels are transformed into natural logarithm (Ln). DLCO = carbon monoxide lung diffusing capacity corrected for hemoglobin concentration; SP = surfactant protein; RAGE = plasma receptor for advanced glycation end products. Note that the strongest relationship was the one between the Immature SPB and DLCO (see also <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0115030#pone-0115030-t004" target="_blank">table 4</a>).</p

Unadjusted simple Pearson correlation pattern between plasma and RBC analytes.

*<p>P<0.05,</p>†<p>P<0.01,</p>‡<p>P<0.001.</p

Demographic and clinical characteristics of CAD patients and Ctrl subjects.

<p>Quantitative variables were expressed as mean ± SD and categorical variables as n (%).</p><p>P value: Wilcoxon test for continous variables and Chi Square test for categorical variables.</p><p>P value adjusted for sex and age after log-transformation of the data.</p

Immunostaining of NO synthase (NOS) protein in human red blood cells (RBCs).

<p>NOS was detected in RBCs from CAD patients (A) and from Ctrl (B). RBCs were incubated with a monoclonal anti eNOS antibody (2.5 µg/ml) and with an anti-mouse conjugated secondary antibody (40 µg/ml; Alexa Fluor488). The samples were mounted with fluorescent mounting medium and examined by laser scanning confocal microscope (LSM710, Carl Zeiss) using a 63×/1.3 oil immersion objective lens. Fluorescent images were captured with a digital camera using the image processor Zen (Carl Zeiss). (C) Fluorescence intensity (densitometric sum of grey) was quantified. Data are expressed as the log median of total fluorescence intensity per field ± interquartile range subtracted of the negative control value. Means derive from n = 10 CAD and n = 10 Ctrl.</p

RBC levels of analytes involved in Arginine/NO pathway.

<p>(A) L-arginine (Arg), L-citrulline (Cit), L-ornithine (Orn) were simultaneously determined by LC-MS/MS. (B) Arg bioavailability and the relative activity of arginase and RBC-NOS enzymes are expressed as Arg/(Orn+Cit) and Orn/Cit ratios, respectively. (C) The endogenous inhibitors asymmetric dimethylarginine (ADMA) and symmetric dimethylarginine (SDMA) were determined by LC-MS/MS. (D) Tetrahydrobiopterin (BH₄) and oxidized biopterins (Box) were detected by HPLC after selective oxidation with iodine. Data are presented as age and sex adjusted geometric means and 95% C.I. Comparisons between groups (CAD, n = 22; Ctrl, n = 20) were performed by covariance analysis, adjusting for age and sex.</p