Immune cell dynamics deconvoluted by single-cell RNA sequencing in normothermic machine perfusion of the liver.

Normothermic machine perfusion (NMP) has emerged as an innovative organ preservation technique. Developing an understanding for the donor organ immune cell composition and its dynamic changes during NMP is essential. We aimed for a comprehensive characterization of immune cell (sub)populations, cell trafficking and cytokine release during liver NMP. Single-cell transcriptome profiling of human donor livers prior to, during NMP and after transplantation shows an abundance of CXC chemokine receptor 1+/2+ (CXCR1+/CXCR2+) neutrophils, which significantly decreased during NMP. This is paralleled by a large efflux of passenger leukocytes with neutrophil predominance in the perfusate. During NMP, neutrophils shift from a pro-inflammatory state towards an aged/chronically activated/exhausted phenotype, while anti-inflammatory/tolerogenic monocytes/macrophages are increased. We herein describe the dynamics of the immune cell repertoire, phenotypic immune cell shifts and a dominance of neutrophils during liver NMP, which potentially contribute to the inflammatory response. Our findings may serve as resource to initiate future immune-interventional studies.

The human C-type lectin-like receptor CLEC-1 is upregulated by TGF-ß and primarily localized in the endoplasmic membrane compartment.

The orphan receptor CLEC-1 is part of a subfamily of C-type lectin-like receptors, which is encoded in the human natural killer gene complex and comprises several pattern recognition receptors important for innate immune functions. As information on human CLEC-1 is still very limited, we aimed to further characterize this receptor. Similar to another subfamily member, LOX-1, expression of CLEC-1 mRNA was detected in myeloid cells as well as in endothelial cells. CLEC-1 protein displayed N-linked glycosylation and formed dimers. However, in contrast to other members of the subfamily, expression levels were upregulated by transforming growth factor (TGF)-ß, but not significantly affected by proinflammatory stimuli. It is intriguing that human CLEC-1 could only be detected intracellularly with a staining pattern resembling endoplasmic reticulum proteins. Neither TGF-ß nor inflammatory stimuli could promote significant translocation to the cell surface. These findings are in accordance with a primarily intracellular localization and function of human CLEC-1.

Mild and moderate hypothermia increases platelet aggregation induced by various agonists: a whole blood in vitro study.

The mechanisms causing temperature-dependent bleeding, especially in hypothermic patients, warrant clarification. Therefore the aim of this study was to investigate platelet aggregation at the clinically important temperature range of 30-34 degrees C. After obtaining informed consent citrated whole blood was drawn from 12 healthy adult male volunteers, who had not taken any medication in the previous 14 days. After venipuncture blood samples were incubated at 37 degrees C until platelet testing. Platelet aggregation was performed in whole blood using the impedance aggregometer Multiplate at five different test temperatures between 30 degrees C and 34 degrees C. Aggregation responses at 37 degrees C served as controls. At temperatures of mild and moderate hypothermia (30-34 degrees C), overall platelet aggregation was increased compared to 37 degrees C. Increases were recorded in response to collagen, thrombin receptor activating peptide and ristocetin between 31 degrees C and 34 degrees C and in response to adenosine diphosphate between 30 degrees C and 34 degrees C. Overall platelet aggregation is increased at mild and moderate hypothermia down to 30 degrees C. These results indicate that bleeding complications reported in mildly hypothermic patients are not due to hypothermia-induced platelet inhibition. The pathomechanism of the overall increased platelet aggregation between 30 degrees C and 34 degrees C requires further detailed study.

Concentration dependence of the spectroscopic and photochemical properties of atomic and molecular oxygen in argon matrices.

Vacuum ultraviolet (VUV) excitation (200-100 nm) and visible emission (300-650 nm) spectra of O2 imbedded in Ar matrices at different concentrations are presented. At 0.1 and 0.2% concentrations a linear increase in the intensities of the excitation and emission spectra is observed. At these concentrations, photolysis of O2 is found to be negligible. At higher concentrations (0.5, 1 and 2%) the normalized intensities of the excitation and emission spectra of O2 decrease. With increasing concentration of O2 the permanent photolysis of O2 increases, which does not correlate, based on the excitation spectra of O in Ar, to the production of isolated O atoms. It has been shown that this anomalous behavior should be due to the formation of van der Waals dimers and oligomers at higher concentrations of O2 that upon photolysis produce ozone.

The conception of the alternative and the decision to divorce.

Despite soaring divorce rates and the effect of divorce on the individual, family, and society, professional scientific literature examining the factors governing the decision to divorce has been scant. The author suggests that the key variable affecting the decision to divorce can best be understood through an exploration of the individual's conception of the alternative. The factors that comprise the conception of the alternative are discussed and the problems inherent in its valid construction by the patient are examined. The therapeutic implementation of this conception is outlined.

Individual speaker influence on relative intelligibility of esophageal speech and artificial larynx speech.

Comparisons were made of the relative intelligibility of esophageal and artificial larynx speech. Care was taken to minimize the variable effects of individual speaker characteristics. For example, rather than relying solely on data comparisons between groups of different speakers, contrasts were also made between samples from subjects who could use both means of alaryngeal speech. Fifteen proficient male laryngectomized speakers were selected. Five used only esophageal speech, five used only artificial larynx speech, and five produced both forms of speech. Recordings were made while the subjects read 50 PB (Phonetically Balanced) words embedded in a carrier phrase and were transcribed by 30 naive listeners. Differences in intelligibility between esophageal and artificial larynx speech resulted when data comparisons were based on different speaker groups. However, differences were not evident when data from the same speakers were compared. The results were interpreted to highlight the possible influence of individual speaker characteristics, rather than differences between communication methods.

The future of alcohology: craft or science?

The authors discuss the problems that have resulted from the influx of professionals into the field of alcoholism, which has historically been dominated by paraprofessional workers. The interaction of the professional alcohologist, who operates from a scientific model, with the paraprofessional worker, whose model of treatment has followed craft lines, has created unique problems and tensions. A synergism has been created which has been detrimental rather than complementary. The authors suggest that the future of the alcoholism field will have to be established along craft (paraprofessional) or scientific (professional) lines because the two models cannot profitably co-exist.