Phytoplankton chemotaxonomy in waters around the Svalbard archipelago reveals high amounts of Chl b and presence of gyroxanthin-diester

Phytoplankton pigment signatures from a cruise in 2005 are herein presented and used as a chemotaxonomic tool for phytoplankton diversity in the Svalbard marine archipelago. Studies from these waters have until recently reported only a few groups of phytoplankton, and while this paper is the first to show that the diversity around Svalbard includes all major phytoplankton pigment groups, the results are seen in relation to other similar studies from the Arctic. We present two potentially important marker pigments: prasinoxanthin, originating from prasinophytes, and gyroxanthin-diester, possibly originating from the temperate- and bloom-forming coccolithophore Emiliania huxleyi. Pigment identification by HPLC revealed a significant amount of Chlorophyll b-containing chlorophyceae, euglenophyceae and prasinophyceae. Prasinoxanthin was present at 50% of the examined stations, typically at Chl a maximum (15–25 m depth), in both Atlantic and Arctic water masses. Gyroxanthin-diester, in contrast to prasinoxanthin, was found only in Atlantic water masses and at low concentrations. Our data may be important for the identification and verification of remotely sensed images of different pigment groups of phytoplankton and their corresponding biomass, typically estimated from Chl a. Remotely sensed presence of coccoliths, indicating E. huxleyi at sea surface, is discussed in relation to water masses and pigment signatures at sea surface and Chl a maximum depths.     

UCSF Chimera, MODELLER, and IMP: an integrated modeling system

Structural modeling of macromolecular complexes greatly benefits from interactive visualization capabilities. Here we present the integration of several modeling tools into UCSF Chimera. These include comparative modeling by MODELLER, simultaneous fitting of multiple components into electron microscopy density maps by IMP MultiFit, computing of small-angle X-ray scattering profiles and fitting of the corresponding experimental profile by IMP FoXS, and assessment of amino acid sidechain conformations based on rotamer probabilities and local interactions by Chimera.     

Basal hyperchlorhydria and its relation to the plasma concentrations of secretin,vasoactive intestinal polypeptide (VIP) and gastrin during prolonged strain

Twenty young men divided into two groups participated in a five day training course with prolonged and heavy physical exercise, calorie supply deficiency and severe sleep deprivation. Basal acid output (BAO) was measured immediately after the course in seven of ten subjects who were given placebo tablets (placebo group) and in four of ten subjects who had a daily intake of 1 g cimetidine (cimetidine-group) during the course. Median BAO increased 3-fold in the placebo subjects (from 2.7 mmol/h to 8.2 mmol/h) but showed no increase in the cimetidine treated subjects. The median fasting plasma concentrations of secretin increased 2–8-fold during the course. Gastric suction for 1 h or ingestion of cimetidine reduced the plasma concentration of secretin by approx. 50%. Vasoactive intestinal polypeptide (VIP) increased 2-fold and was not influenced by reduction of gastric acid. The placebo group showed a small increase (P < 0.05) in plasma concentration of gastrin on day two during the course.The study shows a marked hyperchlorhydria which partly explains the fasting hypersecretinemia found during prolonged strain. This strain-induced hyperchlorhydria could be abolished by treatment with the selective H₂-receptor antagonist cimetidine.     

Studies of Atlantic salmon (Salmo salar L.) blood, spleen and head kidney leucocytes using specific monoclonal antibodies, immunohistochemistry and flow cytometry

Monoclonal antibodies (mabs) raised against Atlantic salmon serum IgM (C7G7 and G2H3) and isolated peripheral blood leucocytes (PBL) (E3D9, C4B6 and D8B3) were applied in this study. Using immunoenzymehistochemistry, immunofluorescence and flow cytometry, the distribution of mab+ cells in blood, spleen and head kidney from Atlantic salmon were studied. Immunostaining on cytospin preparations and flow cytometry of isolated PBL showed that the Ig+ cells recognised by C7G7 and G2H3 were mononuclear leucocytes (MNL). The cytospin preparations showed some Ig+ cells with strong cytoplasmic staining, most likely plasma cells. The salmon blood neutrophils were the only E3D9+ cells in cytospin preparations of PBL, and E3D9 recognised about 94% of the defined neutrophil fraction in flow cytometry. The reactivities of C4B6 and D8B3 were to a large degree similar in both immunoenzymehistochemistry and flow cytometry, recognising both MNL and blood neutrophils. Immunofluorescence double staining of PBL with C4B6 and D8B3 showed double staining of all mab+ cells and D8B3 was apparently not able to block the binding of C4B6 to PBL. Immunofluorescence double staining of PBL also revealed more E3D9+ than C4B6+ neutrophils. In immunostaining on cryostat sections of spleen and head kidney, staining of cells was observed with all the mabs, the head kidney generally containing more positive cells than the spleen. Some potential applications for immunological studies using these mabs are suggested.     

Peripheral blood and head kidney leucocyte populations during out-of-season (0+) parr-smolt transformation and seawater transfer of Atlantic salmon (Salmo salar L.)

Using monoclonal antibodies (MAb) and flow cytometry, Atlantic salmon neutrophils and Ig+ cells in blood and head kidney were studied in under-yearling out-of-season (0+) smolts, and 2 and 4 weeks after transfer to seawater. The parr-smolt transformation was induced using a phase advanced simulated natural photoperiod regime, and sampling of four fish was performed at regular intervals, starting on the date of the photoperiod initiation. During the freshwater period the proportion of neutrophils in the head kidney leucocytes (HKL) remained quite stable and only gradual changes in Ig+ cells were observed. In the peripheral blood leucocytes (PBL), the proportion of neutrophils markedly increased during the last month prior to seawater transfer. The most notable changes in the proportions of MAb+ leucocytes were observed in PBL after seawater transfer, with a significant increase in Ig+ cells and a significant decrease in neutrophils after two weeks in seawater. In the freshwater samples, although there were fluctuations, a decrease in the numbers of total leucocytes per millilitre blood and per gram head kidney during parr-smolt transformation was observed. The number of MAb+ cells in blood appeared to be relatively stable, while the number in head kidney tended to decrease. Following seawater transfer, the numbers of total and MAb+ leucocytes in both blood and head kidney increased markedly. The results suggest that changes in both distribution and numbers of leucocytes in peripheral blood and head kidney take place during parr-smolt transformation, and that marked changes are associated with seawater transfer. Some mechanisms possibly involved are indicated.     

Lack of pro-inflammatory cytokine mobilization predicts poor prognosis in patients with acute heart failure

AimsThe aim of this study was to gain insight in the inflammatory response in acute heart failure (AHF) by assessing (1) plasma cytokine profiles and (2) prognostic value of circulating cytokines in AHF patients.Methods and resultsPlasma levels of 26 cytokines were quantified by multiplex protein arrays in 36 patients with congestive AHF, characterized by echocardiographic, radiologic, and clinical examinations on admission, during hospitalization and at discharge. Recurrent AHF leading to death or readmission constituted the combined end point, and all patients were followed for 120 days after discharge. Levels of 15 of the measured cytokines were higher in AHF than in healthy subjects (n = 22) on admission. Low levels of MCP-1, IL-1β and a low IL-1β/IL-1ra ratio predicted fatal and non-fatal AHF within 120 days. Patients with low circulating levels of IL-1β had lower left ventricular ejection fraction and higher levels of N-terminal pro-B-type natriuretic peptide, while patients with low levels of MCP-1 had higher E/E′ and inferior caval vein diameter, than patients with high levels.ConclusionImmune activation, reflected in increased cytokine levels, is present in AHF patients. Interestingly, failure to increase secretion of IL-1β and MCP-1 during AHF is associated with poor outcome.     

Monocarboxylate Transporters 1–4 in NSCLC: MCT1 Is an Independent Prognostic Marker for Survival

Introduction

Monocarboxylate transporters (MCTs) 1–4 are lactate transporters crucial for cancers cells adaption to upregulated glycolysis. Herein, we aimed to explore their prognostic impact on disease-specific survival (DSS) in both cancer and tumor stromal cells in NSCLC.

Methods

Tissue micro arrays (TMAs) were constructed, representing both cancer and stromal tumor tissue from 335 unselected patients diagnosed with stage I–IIIA NSCLC. Immunohistochemistry was used to evaluate the expression of MCT1-4.

Results

In univariate analyses; ↓MCT1 (P = 0.021) and ↑MCT4 (P = 0.027) expression in cancer cells, and ↑MCT1 (P = 0.003), ↓MCT2 (P = 0.006), ↓MCT3 (P = 0.020) expression in stromal cells correlated significantly with a poor DSS. In multivariate analyses; ↓MCT1 expression in cancer cells (HR: 1.9, CI 95%: 1.3–2.8, P = 0.001), ↓MCT2 (HR: 2.4, CI 95%: 1.5–3.9, P<0.001), ↓MCT3 (HR: 1.9, CI 95%: 1.1–3.5, P = 0.031) and ↑MCT1 expression in stromal cells (HR: 1.7, CI 95%: 1.1–2.7, P = 0.016) were significant independent poor prognostic markers for DSS.

Conclusions

We provide novel information of MCT1 as a candidate marker for prognostic stratification in NSCLC. Interestingly, MCT1 shows diverging, independent prognostic impact in the cancer cell and stromal cell compartments.     

Linking life‐history theory and metabolic theory explains the offspring size‐temperature relationship

Temperature often affects maternal investment in offspring. Across and within species, mothers in colder environments generally produce larger offspring than mothers in warmer environments, but the underlying drivers of this relationship remain unresolved. We formally evaluated the ubiquity of the temperature–offspring size relationship and found strong support for a negative relationship across a wide variety of ectotherms. We then tested an explanation for this relationship that formally links life‐history and metabolic theories. We estimated the costs of development across temperatures using a series of laboratory experiments on model organisms, and a meta‐analysis across 72 species of ectotherms spanning five phyla. We found that both metabolic and developmental rates increase with temperature, but developmental rate is more temperature sensitive than metabolic rate, such that the overall costs of development decrease with temperature. Hence, within a species’ natural temperature range, development at relatively cooler temperatures requires mothers to produce larger, better provisioned offspring.