Outcomes in patients with gunshot wounds to the brain.

Introduction:Gunshot wounds to the brain (GSWB) confer high lethality and uncertain recovery. It is unclear which patients benefit from aggressive resuscitation, and furthermore whether patients with GSWB undergoing cardiopulmonary resuscitation (CPR) have potential for survival or organ donation. Therefore, we sought to determine the rates of survival and organ donation, as well as identify factors associated with both outcomes in patients with GSWB undergoing CPR. Methods:We performed a retrospective, multicenter study at 25 US trauma centers including dates between June 1, 2011 and December 31, 2017. Patients were included if they suffered isolated GSWB and required CPR at a referring hospital, in the field, or in the trauma resuscitation room. Patients were excluded for significant torso or extremity injuries, or if pregnant. Binomial regression models were used to determine predictors of survival/organ donation. Results:825 patients met study criteria; the majority were male (87.6%) with a mean age of 36.5 years. Most (67%) underwent CPR in the field and 2.1% (n=17) survived to discharge. Of the non-survivors, 17.5% (n=141) were considered eligible donors, with a donation rate of 58.9% (n=83) in this group. Regression models found several predictors of survival. Hormone replacement was predictive of both survival and organ donation. Conclusion:We found that GSWB requiring CPR during trauma resuscitation was associated with a 2.1% survival rate and overall organ donation rate of 10.3%. Several factors appear to be favorably associated with survival, although predictions are uncertain due to the low number of survivors in this patient population. Hormone replacement was predictive of both survival and organ donation. These results are a starting point for determining appropriate treatment algorithms for this devastating clinical condition. Level of evidence:Level II

Optical and structural analysis of solar selective absorbing coatings based on AlSiOx:W cermets

It is reported in this work the development and study of the optical and structural properties of a solar selective absorber cermet based on AlSiOx:W. A four-layer composite film structure, W/AlSiOx:W(HA)/AlSiOx:W(LA)/AlSiOx, was deposited on stainless steel substrates using the magnetron sputtering deposition method. Numerical calculations were performed to simulate the spectral properties of multilayer stacks with varying metal volume fraction cermets and film thickness. The chemical analysis was performed using X-ray photoelectron spectroscopy and the results show that in the high metal volume fraction cermet layer, AlSiOx:W(HA), about one third of W atoms are in the W-O oxidation state, another third in the Wx+ oxidation state and the last third in the W4+, W5+ and W6+ oxidation states. The X-ray diffractograms of AlSiOx:W layers show a broad peak indicating that both, W and AlSiOx, are amorphous. These results indicate that this film structure has a good spectral selective property that is suitable for solar thermal applications, with the coatings exhibiting a solar absorptance of 94-95.5% and emissivities of 8-9% (at 100 degrees C) and 10-14% (at 400 degrees C). The samples were subjected to a thermal annealing at 450 degrees C, in air, and 580 degrees C, in vacuum and showed very good oxidation resistance and thermal stability. Morphological characterizations were carried out using scanning electron microscopy and atomic force microscopy. Rutherford Backscattering experiments were also performed to analyze the tungsten depth profile.The authors acknowledge the support of the Portuguese Foundation for Science and Technology (FCT) in the framework of the Strategic Funding UID/FIS/04650/2013. The authors are also grateful to the financial support of FCT, POCI and PORL operational programs through the project POCI-01-0145-FEDER-016907 (PTDC/CTM-ENE/2882/2014), co-financed by European community fund FEDER. The authors also acknowledge GIST Japan for using the XPS-Kratos.info:eu-repo/semantics/publishedVersio

Allele-Independent Turnover of Human Leukocyte Antigen (HLA) Class Ia Molecules.

Major histocompatibility complex class I (MHCI) glycoproteins present cytosolic peptides to CD8+ T cells and regulate NK cell activity. Their heavy chains (HC) are expressed from up to three MHC gene loci (human leukocyte antigen [HLA]-A, -B, and -C in humans), whose extensive polymorphism maps predominantly to the antigen-binding groove, diversifying the bound peptide repertoire. Codominant expression of MHCI alleles is thus functionally critical, but how it is regulated is not fully understood. Here, we have examined the effect of polymorphism on the turnover rates of MHCI molecules in cell lines with functional MHCI peptide loading pathways and in monocyte-derived dendritic cells (MoDCs). Proteins were labeled biosynthetically with heavy water (2H2O), folded MHCI molecules immunoprecipitated, and tryptic digests analysed by mass spectrometry. MHCI-derived peptides were assigned to specific alleles and isotypes, and turnover rates quantified by 2H incorporation, after correcting for cell growth. MHCI turnover half-lives ranged from undetectable to a few hours, depending on cell type, activation state, donor, and MHCI isotype. However, in all settings, the turnover half-lives of alleles of the same isotype were similar. Thus, MHCI protein turnover rates appear to be allele-independent in normal human cells. We propose that this is an important feature enabling the normal function and codominant expression of MHCI alleles

HLA-B fractional synthesis in unstimulated MoDCs.

<p>Analysis as in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0161011#pone.0161011.g006" target="_blank">Fig 6</a>, except that separate curve fits are shown for HD2 (p = 0.04, F test). The significance of this result is doubtful, as explained in the text. B*27+ donors are identified; note that B27 allele-specific peptides proved suitable for analysis in HD6 and 7, but not in HD4 and 5.</p

MHCI turnover in LCL721 cells.

<p>LCL721 cells were labeled with ≈ 5% ²H₂O in media and folded MHCI molecules immunoprecipitated with W6/32. ²H incorporation into tryptic peptides was quantified by LC-MS. (A-C) Fractional synthesis was calculated for different peptides derived from HLA-A (A), HLA-B (B), and HLA-C molecules (C) (mean ± SD of different mass isotopomers) and plotted against labeling time. Full sequences and analytical metrics for all informative peptides (identified by four amino acids in single-letter code or by charge) are in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0161011#pone.0161011.s004" target="_blank">S2 Table</a>. In (A) and (B), allele- and isotype-specific peptides exhibited no significant differences in fractional protein synthesis (p = 0.32 and p = 0.29, respectively, by F test); in (C), only C1-specific peptides were identified. Single-exponential curve fits (with 95% confidence intervals) are based on a pooled analysis of all peptides from each isotype. (D) Exponential growth of LCL721 cells during ²H₂O labeling. The corresponding time course of the fraction of new cells is shown in panels (A-C), for comparison with protein synthesis. Panels (A-D) were from the same experiment. (E) Fractional synthesis rates (per hour, mean ± SEM) of MHCI isotypes (from (A-C)), compared to fractional cell growth rates (from (D)). Two independent experiments are shown. Fractional synthesis rates for individual peptides are in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0161011#pone.0161011.s004" target="_blank">S2 Table</a>. (F) Turnover rates of different MHCI isotypes, calculated from the excess of mean fractional protein synthesis rates over the cell growth rate.</p

Effect of ²H₂O labeling on peptide mass isotopomer distributions.

<p>(A) Mass isotopomer distributions of a MHCI-derived, B isotype-specific tryptic peptide from KG-1 cells after labeling with ²H₂O for various times. Lines connect data at each time point. Within error, each mass isotopomer changed from its initial (unlabeled) to final plateau (fully-labeled) value at the same rate, which is identical to the rate of protein fractional synthesis. (B) For the same peptide, MIDA models for the unlabeled and fully-labeled mass isotopomer distributions (dashed and solid lines, respectively) were compared with experimental data (symbols). RMSD values were 0.20% and 0.25%, respectively, for unlabeled and fully-labeled samples).</p

HLA-C fractional synthesis in unstimulated MoDCs.

<p>Analysis as in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0161011#pone.0161011.g006" target="_blank">Fig 6</a>.</p

MHCI turnover in KG-1 cells.

<p>Proliferating KG-1 cells were labeled with ≈ 5% ²H₂O in media and MHCI molecules immunoprecipitated with W6/32. ²H incorporation into selected peptides (<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0161011#pone.0161011.s003" target="_blank">S1 Table</a>; identified here by the four N-terminal amino acids and assigned to isotypes and alleles as shown) was quantified by LC-MS. One of two independent experiments is shown here; <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0161011#pone.0161011.s003" target="_blank">S1 Table</a> summarizes results for both. (A-C) Fractional synthesis was calculated for different peptides derived from HLA-A (A), HLA-B (B), and HLA-C molecules (C) (mean ± SD of the informative mass isotopomers) and plotted against time. In (B) and (C), allele- and isotype-specific peptides exhibited no significant differences in fractional protein synthesis (p = 0.24 and p = 0.55, respectively, by F test). Single-exponential curve fits (with 95% confidence intervals) are based on a pooled analysis of all peptides from each isotype. (D) Exponential growth of KG-1 cells during ²H₂O labeling. The corresponding time course of the fraction of new cells is shown in panels (A-C) for comparison with protein synthesis. (E) Fractional synthesis rates (per hour, mean ± SEM) of MHCI isotypes (from (A-C)), compared with cell growth (from (D)). The differences between HLA-C and the other isotypes, and those between the MHCI fractional synthesis rates and cell growth, were significant (each p < 0.0001, F test). (F) Turnover half-lives of different MHCI isotypes, calculated from the excess of mean fractional protein synthesis rates over the cell growth rate.</p