Organisms living in or on the sediment layer of water bodies constitute the benthos fauna, which is known to harbour a large number of species of diverse taxonomic groups. The benthos plays a significant role in the nutrient cycle and it is, therefore, of high ecological relevance. Here, we have explored a DNA-taxonomic approach to access the meiobenthic organismic diversity, by focusing on obtaining signature sequences from a part of the large ribosomal subunit rRNA (28S), the D3–D5 region. To obtain a broad representation of taxa, benthos samples were taken from 12 lakes in Germany, representing different ecological conditions. In a first approach, we have extracted whole DNA from these samples, amplified the respective fragment by PCR, cloned the fragments and sequenced individual clones. However, we found a relatively large number of recombinant clones that must be considered PCR artefacts. In a second approach we have, therefore, directly sequenced PCR fragments that were obtained from DNA extracts of randomly picked individual organisms. In total, we have obtained 264 new unique sequences, which can be readily placed into taxon groups, based on phylogenetic comparison with currently available database sequences. The group with the highest taxon abundance were nematodes and protozoa, followed by chironomids. However, we find also that we have by far not exhausted the diversity of organisms in the samples. Still, our data provide a framework within which a meiobenthos DNA signature sequence database can be constructed, that will allow to develop the necessary techniques for studying taxon diversity in the context of ecological analysis. Since many taxa in our analysis are initially only identified via their signature sequences, but not yet their morphology, we propose to call this approach ‘reverse taxonomy’.

Macrophages are important in the activation of innate immune responses and in a tissue-specific manner in the maintenance of organ homeostasis. Testicular macrophages (TM), which reside in the testicular interstitial space, comprise the largest leukocyte population in the testes and are assumed to play a relevant function in maintaining testicular immune privilege. Numerous studies have indicated that the interstitial fluid (IF) surrounding the TM has immunosuppressive properties, which may influence the phenotype of TM. However, the identity of the immunosuppressive molecules present in the IF is poorly characterized. We show that the rat testicular IF shifted GM-CSF–induced M1 toward the M2 macrophage phenotype. IF-polarized M2 macrophages mimic the properties of TM, such as increased expression of CD163, high secretion of IL-10, and low secretion of TNF-α. In addition, IF-polarized macrophages display immunoregulatory functions by inducing expansion of immunosuppressive regulatory T cells. We further found that corticosterone was the principal immunosuppressive molecule present in the IF and that the glucocorticoid receptor is needed for induction of the testis-specific phenotype of TM. In addition, TM locally produce small amounts of corticosterone, which suppresses the basal expression of inflammatory genes as a means to render TM refractory to inflammatory stimuli. Taken together, these results suggest that the corticosterone present in the testicular environment shapes the immunosuppressive function and phenotype of TM and that this steroid may play an important role in the establishment and sustenance of the immune privilege of the testis.

Intraoperative hypotension is associated with acute kidney injury (AKI). Clinicians thus frequently use vasopressors, such as norepinephrine, to maintain blood pressure. However, vasopressors themselves might promote AKI. We sought to determine whether both intraoperative hypotension and cumulative intraoperative norepinephrine dose are independently associated with postoperative AKI in patients undergoing noncardiac surgery. This was a retrospective cohort analysis of 38 338 adult male and female patients who had noncardiac surgery. The primary outcome was AKI within the first 7 postoperative days. We performed adjusted multivariable logistic regression analysis to determine whether intraoperative hypotension (quantified as area under a mean arterial pressure [MAP] of 65 mm Hg) and cumulative intraoperative norepinephrine dose were independently associated with AKI. The median (25th percentile, 75th percentile) area under a MAP of 65 mm Hg was 0.09 (0.02, 0.22) mm Hg∗day in patients with AKI and 0.05 (0.01, 0.14) mm Hg∗day in patients without AKI (P<0.001). The cumulative intraoperative norepinephrine dose was 1.92 (0.00, 13.09) μg kg^-1 in patients with AKI and 0.00 (0.00, 0.00) μg kg^-1 in patients without AKI (P<0.001). Both the area under a MAP of 65 mm Hg (odds ratio 1.55 [95% confidence interval 1.17-2.02] per mm Hg∗day; P=0.002) and the cumulative intraoperative norepinephrine dose (odds ratio 1.02 [95% confidence interval 1.01-1.02] per μg kg^-1; P<0.001) were independently associated with AKI. Both intraoperative hypotension and cumulative intraoperative norepinephrine dose were independently associated with postoperative AKI in patients undergoing noncardiac surgery. Pending results of trials testing whether these relationships are causal, it seems prudent to avoid both profound hypotension and high norepinephrine doses in adults undergoing noncardiac surgery.

Background: It is crucial to rapidly identify sepsis so that adequate treatment may be initiated. Accordingly, the Sequential Organ Failure Assessment (SOFA) and the quick SOFA (qSOFA) scores are used to evaluate intensive care unit (ICU) and non-ICU patients, respectively. As demand for ICU beds rises, the intermediate care unit (IMCU) carries greater importance as a bridge between the ICU and the regular ward. This study aimed to examine the ability of SOFA and qSOFA scores to predict suspected infection and mortality in IMCU patients. Methods: Retrospective data analysis included 13,780 surgical patients treated at the IMCU, ICU, or both between January 01, 2012, and September 30, 2018. Patients were screened for suspected infection (i.e., the commencement of broad-spectrum antibiotics) and then evaluated for the SOFA score, qSOFA score, and the 1992 defined systemic inflammatory response syndrome (SIRS) criteria. Results: Suspected infection was detected in 1306 (18.3%) of IMCU, 1365 (35.5%) of ICU, and 1734 (62.0%) of IMCU/ICU encounters. Overall, 458 (3.3%) patients died (IMCU 45 [0.6%]; ICU 250 [6.5%]; IMCU/ICU 163 [5.8%]). All investigated scores failed to predict suspected infection independently of the analyzed subgroup. Regarding mortality prediction, the qSOFA score performed sufficiently within the IMCU cohort (AUCROC SIRS 0.72 [0.71–0.72]; SOFA 0.52 [0.51–0.53]; qSOFA 0.82 [0.79–0.84]), while the SOFA score was predictive in patients of the IMCU/ICU cohort (AUCROC SIRS 0.54 [0.53–0.54]; SOFA 0.73 [0.70–0.77]; qSOFA 0.59 [0.58–0.59]). Conclusions: None of the assessed scores was sufficiently able to predict suspected infection in surgical ICU or IMCU patients. While the qSOFA score is appropriate for mortality prediction in IMCU patients, SOFA score prediction quality is increased in critically ill patients.