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The article discusses results of a study that investigates the composition of the phytoplankton and microzooplankton assemblage and its quantitative and qualitative response to iron addition. The study methodology is described, including collecting and fixing of duplicate samples with hexamine-buffered formaldehyde and Lugol. The study showed that the plankton community of the eddy was characteristic of the late stage of the seasonal cycle. It notes that small flagellates accounted for about 70 percent to 80 percent of the phytoplankton biomass at both the in-patch and out-patch stations.

The article discusses results of a study that examines the development of the nanoplankton community and micro and nanozooplankton grazing in the Antarctic Circumpolar Current (ACC). The study methodology is described, including collecting of water samples for nanoplankton, staining and filtration. The study showed that grazers consumed about 50 percent of phytoplankton production. Meanwhile, phaeopigments concentrations in surface waters were more than twice than those found in previous iron fertilization studies. Flow cytometry analyses showed that apparent growth and grazing-mediated mortality rates of picoheterotrophs have no difference inside and outside the fertilized patch.

The article discusses results of a study that determines the phytoplankton physiology as a proxy of iron stimulation. The study methodology is described, including immersion of the calibrated Chelsea Fastracka in a plastic tank with moon pool water continuously pumped through the dark cell of the instrument. An overview of the acquisition procedure set tup by Rüdiger Röttgers and his team in a previous experiment is given, including keeping the instrument running all the time and activation of a remote connection to have a remote control of the software when needed.

The article discusses results of a study that determines the primary productivity of carbon-14 and the response of different phytoplankton size fractions during the iron fertilization. The study methodology is described, including the use of clean technique to transfer known volume of samples into polycarbonate bottles to reduce trace metal contamination. The study showed that productivity values inside the fertilized patch increased and remained high after the second fertilisation. Also discussed are the results of a study of the photosynthetic physiology of phytoplankton in the water column.

The redox speciation of iron was determined during the iron fertilization LOHAFEX and for the first time, the chemiluminescence assay of filtered and unfiltered samples was systematically compared. We hypothesize that higher chemiluminescence in unfiltered samples was caused by Fe(II) adsorbed onto biological particles. Dissolved and particulate Fe(II) increased in the mixed layer steadily 6-fold during the first two weeks and decreased back to initial levels by the end of LOHAFEX. Both Fe(II) forms did not show diel cycles downplaying the role of photoreduction. The chemiluminescence of unfiltered samples across the patch boundaries showed strong gradients, correlated significantly to biomass and the photosynthetic efficiency and were higher at night, indicative of a biological control. At 150 m deep, a secondary maximum of dissolved Fe(II) was associated with maxima of nitrite and ammonium despite high oxygen concentrations. We hypothesize that during LOHAFEX, iron redox speciation was mostly regulated by trophic interactions., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Background: Delirium is a common and serious complication of inpatient hospital care in older patients. The current approaches to prevention and treatment followed in German hospitals are inconsistent. The aim of this study was to test the effectiveness of a standardized multiprofessional approach to the management of delirium in inpatients., Methods: The patients included in the study were all >65 years old, were treated for at least 3 days on an internal medicine, trauma surgery, or orthopedic ward at Münster University Hospital between January 2016 and December 2017, and showed cognitive deficits on standardized screening at the time of admission (a score of ≤=25 on the Montreal Cognitive Assessment [MoCA] test). Patients in the intervention group received standardized delirium prevention and treatment measures; those in the control group did not. The primary outcomes measured were the incidence and duration of delirium during the hospital stay; the secondary outcomes measured were cognitive deficits relevant to daily living at 12 months after discharge (MoCA and Instrumental Activities of Daily Living [I-ADL])., Results: The data of 772 patients were analyzed. Both the rate and the duration of delirium were lower in the intervention group than in the control group (6.8% versus 20.5%, odds ratio 0.28, 95% confidence interval [0.18; 0.45]; 3 days [interquartile range, IQR 2-4] versus 6 days [IQR 4-8]). A year after discharge, the patients with delirium in the intervention group showed fewer cognitive deficits relevant to daily living than those in the control group (I-ADL score 2.5 [IQR 2-4] versus 1 [IQR 1-2], P = 0.02)., Conclusion: Structured multiprofessional management reduces the incidence and duration of delirium and lowers the number of lasting cognitive deficits relevant to daily living after hospital discharge.

Due to demographic changes in the population and the development of novel immunosuppressive agents, an increasing number of trauma and orthopedic patients are taking concomitant immunosuppressive medication. These drugs might interfere with the healing process and can possibly retard or prevent wound and fracture healing and lead to a higher risk of infections. In these complex situations a structured and interdisciplinary process during hospital admission should preoperatively evaluate the possibility of interrupting immunosuppressive medications for the perioperative treatment period without risking a relapse of the underlying disease and which surgical approach should be individually selected for the patient.

Semiautomated methods for microscopic image acquisition, image analysis, and taxonomic identification have repeatedly received attention in diatom analysis. Less well studied is the question whether and how such methods might prove useful for clarifying the delimitation of species that are difficult to separate for human taxonomists. To try to answer this question, three very similar Fragilariopsis species endemic to the Southern Ocean were targeted in this study: F. obliquecostata, F. ritscheri, and F. sublinearis. A set of 501 extended focus depth specimen images were obtained using a standardized, semiautomated microscopic procedure. Twelve diatomists independently identified these specimen images in order to reconcile taxonomic opinions and agree upon a taxonomic gold standard. Using image analyses, we then extracted morphometric features representing taxonomic characters of the target taxa. The discriminating ability of individual morphometric features was tested visually and statistically, and multivariate classification experiments were performed to test the agreement of the quantitatively defined taxa assignments with expert consensus opinion. Beyond an updated differential diagnosis of the studied taxa, our study also shows that automated imaging and image analysis procedures for diatoms are coming close to reaching a broad applicability for routine use., (© 2018 The Authors Journal of Phycology published by Wiley Periodicals, Inc. on behalf of Phycological Society of America.)

A dominant Antarctic ecological paradigm suggests that winter sea ice is generally the main feeding ground for krill larvae. Observations from our winter cruise to the southwest Atlantic sector of the Southern Ocean contradict this view and present the first evidence that the pack-ice zone is a food-poor habitat for larval development. In contrast, the more open marginal ice zone provides a more favourable food environment for high larval krill growth rates. We found that complex under-ice habitats are, however, vital for larval krill when water column productivity is limited by light, by providing structures that offer protection from predators and to collect organic material released from the ice. The larvae feed on this sparse ice-associated food during the day. After sunset, they migrate into the water below the ice (upper 20 m) and drift away from the ice areas where they have previously fed. Model analyses indicate that this behaviour increases both food uptake in a patchy food environment and the likelihood of overwinter transport to areas where feeding conditions are more favourable in spring.

There is a controversy discussion about the contribution of the genus Phaeocystis to the vertical carbon export with evidence for and against sedimentation of Phaeocystis. So far, the presence of Phaeocystis in sinking matter was investigated with methods depending on morphological features (microscopy) and fast degradable substances (biochemical analyses). In this study, we determine the occurrence and abundance of Phaeocystis antarctica in short-term sediment traps and the overlying water column during a 12-day time period in the Atlantic sector of the Southern Ocean with 454-pyrosequencing and microscopy counting. In the sediment trap samples, we only found few sequences belonging to Phaeocystis, which was not reflecting the situation in the water column above. The cell counts showed the same results. We conclude that Phaeocystis cells are not generally transported downwards by active sinking or other sinking processes., (© 2016 John Wiley & Sons Ltd.)

Diatoms of the iron-replete continental margins and North Atlantic are key exporters of organic carbon. In contrast, diatoms of the iron-limited Antarctic Circumpolar Current sequester silicon, but comparatively little carbon, in the underlying deep ocean and sediments. Because the Southern Ocean is the major hub of oceanic nutrient distribution, selective silicon sequestration there limits diatom blooms elsewhere and consequently the biotic carbon sequestration potential of the entire ocean. We investigated this paradox in an in situ iron fertilization experiment by comparing accumulation and sinking of diatom populations inside and outside the iron-fertilized patch over 5 wk. A bloom comprising various thin- and thick-shelled diatom species developed inside the patch despite the presence of large grazer populations. After the third week, most of the thinner-shelled diatom species underwent mass mortality, formed large, mucous aggregates, and sank out en masse (carbon sinkers). In contrast, thicker-shelled species, in particular Fragilariopsis kerguelensis, persisted in the surface layers, sank mainly empty shells continuously, and reduced silicate concentrations to similar levels both inside and outside the patch (silica sinkers). These patterns imply that thick-shelled, hence grazer-protected, diatom species evolved in response to heavy copepod grazing pressure in the presence of an abundant silicate supply. The ecology of these silica-sinking species decouples silicon and carbon cycles in the iron-limited Southern Ocean, whereas carbon-sinking species, when stimulated by iron fertilization, export more carbon per silicon. Our results suggest that large-scale iron fertilization of the silicate-rich Southern Ocean will not change silicon sequestration but will add carbon to the sinking silica flux.

Fertilization of the ocean by adding iron compounds has induced diatom-dominated phytoplankton blooms accompanied by considerable carbon dioxide drawdown in the ocean surface layer. However, because the fate of bloom biomass could not be adequately resolved in these experiments, the timescales of carbon sequestration from the atmosphere are uncertain. Here we report the results of a five-week experiment carried out in the closed core of a vertically coherent, mesoscale eddy of the Antarctic Circumpolar Current, during which we tracked sinking particles from the surface to the deep-sea floor. A large diatom bloom peaked in the fourth week after fertilization. This was followed by mass mortality of several diatom species that formed rapidly sinking, mucilaginous aggregates of entangled cells and chains. Taken together, multiple lines of evidence-although each with important uncertainties-lead us to conclude that at least half the bloom biomass sank far below a depth of 1,000 metres and that a substantial portion is likely to have reached the sea floor. Thus, iron-fertilized diatom blooms may sequester carbon for timescales of centuries in ocean bottom water and for longer in the sediments.

In order to test whether morphological variations within Gephyrocapsa oceanica var. typica Kamptner 1943 reflect genotypic variation or phenotypic responses to environmental conditions, culture experiments of six strains of G. oceanica collected at different locations in the North Atlantic and Mediterranean have been carried out under different temperature and nutrients conditions. All morphological, and physiological data suggest the presence of two species or subspecies within G. oceanica var typica that correspond morphologically to Gephyrocapsa "Larger" and possibly to Gephyrocapsa "Equatorial" as previously defined from Holocene sediments. Given the importance of Gephyrocapsa species for the carbon cycle in the past, genetic studies on this group are of major interest to the understanding of past climate change and plankton evolution., (Copyright 2009 Elsevier GmbH. All rights reserved.)

Objective: To assess the comprehensive effects of raloxifene hydrochloride on retinal, choroidal and retrobulbar hemodynamics and on visual function in post-menopausal women., Design: Twenty-four post-menopausal women (age 55 +/- 3.8 years) were recruited for this cross-sectional study: 12 received placebo and 12 received raloxifene hydrochloride 60 mg once a day for 3 months. Baseline measurements of both groups included heart rate (HR), blood pressure (BP), visual acuity, contrast sensitivity and intraocular pressure (IOP) for both eyes. A comprehensive ocular blood flow (OBF) assessment was obtained for each patient in a randomly chosen study eye. Retinal blood flow data was obtained using confocal scanning laser Doppler flowmetry [Heidelberg Retinal Flowmeter (HRF)]. Color Doppler imaging (CDI) was used to assess retrobulbar hemodynamics in the ophthalmic, central retinal, short nasal and temporal posterior ciliary arteries. Baseline vision and hemodynamics in post-menopausal subjects were compared using paired Student's t tests, and the percentage change in baseline versus 3-month parameters was analyzed., Results: There were no statistically significant differences between 3 months of raloxifene therapy and placebo in terms of age, HR, arterial or mean BP, visual acuity, contrast sensitivity, IOP or retinal or retrobulbar blood flow., Conclusion: Raloxifene therapy at 60 mg/day had no clinically significant impact on BP, IOP or OBF in post-menopausal women.

Morphological analysis of Gephyrocapsa spp. in plankton samples confirms the existence of five out of six morphotypes that were previously reported from Holocene sediments. Our data suggest a much higher diversity within the genus Gephyrocapsa than the currently accepted species circumscriptions. Furthermore, we confirm the morphological species delineations made by Kamptner that allow the separation of three morphological groups within the genus Gephyrocapsa: one group with large bridge angles (G. oceanica var. typica Kamptner 1943), a second group with small bridge angles (G. oceanica var. californiensis Kamptner 1956) and a third group of small coccoliths (G. aperta Kamptner 1963). However, a seemingly continuous transition from small to large coccoliths within G. oceanica var. typica along a temperature gradient points either to a high phenotypic plasticity of G. oceanica var. typica or numerous sibling species highly adapted to specific environmental conditions. Testing of these hypotheses is of utmost importance to understanding the diversity of marine plankton and its evolution, and to assessing the impact of future and past environmental change on primary producers such as coccolithophorids.

Barbiturates are frequently used for the treatment of intracranial hypertension after brain injury but their application is associated with a profound increase in the infection rate. The mechanism of barbiturate-induced failure of protective immunity is still unknown. We provide evidence that nuclear factor of activated T cells (NFAT), an essential transcription factor in T cell activation, is a target of barbiturate-mediated immunosuppression in human T lymphocytes. Treatment of primary CD3+ lymphocytes with barbiturates inhibited the PMA and ionomycin induced increase in DNA binding of NFAT, whereas the activity of other transcription factors, such as Oct-1, SP-1, or the cAMP response element-binding protein, remained unaffected. Moreover, barbiturates suppressed the expression of a luciferase reporter gene under control of NFAT (stably transfected Jurkat T cells), and of the cytokine genes interleukin-2 and interferon-gamma that contain functional binding motifs for NFAT within their regulatory promotor domains (human peripheral blood CD3+ lymphocytes). Neither GABA receptor-initiated signaling nor direct interactions of barbiturates with nuclear proteins affected the activity of NFAT. In contrast, barbiturates suppressed the calcineurin-dependent dephosphorylation of NFAT in intact T cells and also inhibited the enzymatic activity of calcineurin in a cell-free system, excluding upstream regulation. Thus, our results demonstrate a novel mechanism of direct inhibition of the calcineurin/calmodulin complex that may explain some of the known immunosuppressive effects associated with barbiturate treatment.

Human neutrophil elastase (HNE) is a serine protease that has been implicated in the abnormal turnover of connective tissue proteins and has been described as an important pathogenic factor in several inflammatory diseases such as rheumatoid arthritis or cystic fibrosis. Here we investigated 17 sesquiterpene lactones (SLs) for their ability to inhibit human neutrophil elastase in an in vitro assay. Podachaenin was the most active compound with an IC(50) value of 7 microM. SLs do not covalently bind to the amino acids of the catalytic triad, thus differing from other elastase inhibitors with a lactone moiety. In contrast to most other biological activities of SLs HNE inhibition is not mediated by alpha,beta-unsaturated carbonyl functions. Ligand binding calculations using the X-ray structure of HNE and the program FlexX revealed structural elements which are a prerequisite for their inhibitory activity.

Many sesquiterpene lactones (Sls) are known to possess anti-inflammatory activities. To gain further insight into their structure-activity relationships and the molecular mechanism of action, four germacranolide sesquiterpene lactones which differ in the skeleton and the number of reactive centers (4beta,15-epoxy-miller-9E-enolide (1), 15-acetoxy-eremantholide B (2), a mixture of 15-(isovaleroyl)/15-(2-methyl-butyryl)-2alpha-acetoxy-miguanin (3), and 15-(2-hydroxy)-isobutyryloxy-micrantholide (4)) were investigated for their effect on production of proinflammatory cytokines (interleukin-1beta [IL-1beta], IL-6, and tumor necrosis factor-alpha [TNF-alpha]) as well as proliferation of concanavalin A (Con A) and lipopolysaccharide (LPS)-stimulated mouse lymphocytes. Compounds 1 and 3 which possess an alpha-methylene-gamma-lactone function and a conjugated carbonyl group induced a half-maximal inhibition of cytokine synthesis in adherent mouse peritoneal exudate cells at micromolar concentrations (IC(50) 0.69-1.70 microM), while compound 4 which contains only an alpha-methylene-gamma-lactone residue was less active (IC(50) > or 38 microM). Interestingly, compound 2, which carries only a conjugated keto group, displayed a potency similar to those of the bifunctional compounds 1 and 3. All four Sls suppressed proliferation of murine lymphocyte at IC(50) concentrations between 0.22 and 5.03 microM. The rank order of potency was 1 = 2 > 3 > 4. Generally, the growth of LPS-stimulated cells was more strongly influenced than those of Con A-activated lymphocytes. This effect was particularly pronounced with 4. Inhibitory concentrations correlated well with those necessary for inhibition of the transcription factor nuclear factor kappaB (NF-kappaB) observed in a previous investigation. Therefore, it can be assumed that NF-kappaB may be involved in the suppressive effect of Sls on cytokine production and lymphocyte proliferation.

Investigation of Podachaenium eminens afforded nine sesquiterpene lactones (Sls) from which costunolide, 7-hydroxycostunolide, santamarin as well as 3-chlorodehydroleucodin are new for this plant and 3,4-dehydro-4-dehydroxypodachaenin (= 3-costoyloxydehydroleucodin) is found for the first time in nature. All isolated Sls were studied for their anti-inflammatory activity using the transcription factor NF-kappa B as a molecular target. NF-kappa B is involved in the synthesis of inflammatory mediators, such as cytokines and chemokines. Except for podachaenin, all compounds completely inhibited NF-kappa B DNA binding in an electrophoretic mobility shift assay at concentrations between 5 and 200 microM without showing any cytotoxic effects. 3,4-Epoxydehydroleucodin possessing an alpha-methylene-gamma-butyrolactone and a second reactive structure element by its epoxy ring alpha,beta to a carbonyl group was most active. Although the majority of the Sls tested in this study were monofunctional only low concentrations of 50 microM were often needed for complete inhibition. Possible reasons are discussed for this result.