Macroalgal morphogenesis induced by waterborne compounds and bacteria in coastal seawater

Axenic gametes of the marine green macroalga Ulva mutabilis Foyn (Ria Formosa, locus typicus) exhibit abnormal development into slow-growing callus-like colonies with aberrant cell walls. Under laboratory conditions, it was previously demonstrated that all defects in growth and thallus development can be completely abolished when axenic gametes are inoculated with a combination of two specific bacterial strains originally identified as Roseo-bacter sp. strain MS2 and Cytophaga sp. strain MS6. These bacteria release diffusible morphogenetic compounds (= morphogens), which act similar to cytokinin and auxin. To investigate the ecological relevance of the waterborne bacterial morphogens, seawater samples were collected in the Ria Formosa lagoon (Algarve, Southern Portugal) at 20 sampling sites and tidal pools to assess their morphogenetic effects on the axenic gametes of U. mutabilis. Specifically the survey revealed that sterile-filtered seawater samples can completely recover growth and morphogenesis of U. mutabilis under axenic conditions. Morphogenetic activities of free-living and epiphytic bacteria isolated from the locally very abundant Ulva species (i.e., U. rigida) were screened using a multiwell-based testing system. The most represented genera isolated from U. rigida were Alteromonas, Pseudoalteromonas and Sulfitobacter followed by Psychrobacter and Polaribacter. Several naturally occurring bacterial species could emulate MS2 activity (= induction of cell divisions) regardless of taxonomic affiliation, whereas the MS6 activity (= induction of cell differentiation and cell wall formation) was species-specific and is probably a feature of difficult-to-culture bacteria. Interestingly, isolated bacteroidetes such as Algoriphagus sp. and Polaribacter sp. could individually trigger complete Ulva morphogenesis and thus provide a novel mode of action for bacterial-induced algal development. This study also highlights that the accumulation of algal growth factors in a shallow water body separated from the open ocean by barrier islands might have strong implications to, for example, the wide usage of natural coastal seawater in algal (land based) aquacultures of Ulva

Survival benefit with checkpoint inhibitors versus chemotherapy is modified by brain metastases in patients with recurrent small cell lung cancer

IntroductionSmall cell lung cancer (SCLC) is a rapidly growing malignancy with early distant metastases. Up to 70% will develop brain metastases, and the poor prognosis of these patients has not changed considerably. The potential of checkpoint inhibitors (CPI) in treating recurrent (r/r) SCLC and their effect on brain metastases remain unclear.MethodsIn this retrospective multicenter study, we analyzed r/r SCLC patients receiving second or further-line CPI versus chemotherapy between 2010 and 2020. We applied multivariable-adjusted Cox regression analysis to test for differences in 1-year mortality and real-world progression. We then used interaction analysis to evaluate whether brain metastases (BM) and/or cranial radiotherapy (CRT) modified the effect of CPI versus chemotherapy on overall survival.ResultsAmong 285 patients, 99 (35%) received CPI and 186 (65%) patients received chemotherapy. Most patients (93%) in the CPI group received nivolumab/ipilimumab. Chemotherapy patients were entirely CPI-naïve and only one CPI patient had received atezolizumab for first-line treatment. CPI was associated with a lower risk of 1-year mortality (adjusted Hazard Ratio [HRadj] 0.59, 95% CI 0.42 to 0.82, p=0.002). This benefit was modified by BM and CRT, indicating a pronounced effect in patients without BM (with CRT: HRadj 0.34, p=0.003; no CRT: HRadj 0.50, p=0.05), while there was no effect in patients with BM who received CRT (HRadj 0.85, p=0.59).ConclusionCPI was associated with a lower risk of 1-year mortality compared to chemotherapy. However, the effect on OS was significantly modified by intracranial disease and radiotherapy, suggesting the benefit was driven by patients without BM

Flodoard of Rheims and the Historiography of the Tenth-Century West

Flodoard of Rheims is one of the most important authors of tenth-century Europe, and the only contemporary historian to document the momentous struggles between kings and nobles in Francia in the wake of the demise of the Carolingian Empire. Flodoard’s era stands at the center of major historiographical debates concerning the nature of political and social change and the origins of European institutions. Yet, despite his singularity, his substantial histories have received little attention from scholars examining the profound transformations of the period. Exploring this discrepancy, this article offers an overview of Flodoard’s career and reviews how his histories have been invoked in some of the great scholarly debates about tenth-century Europe. It further proposes to recontextualize Flodoard and to reread his histories from the bottom up in order to gain a subtler understanding of how one contemporary perceived and represented the dramatic events and changes taking place around him

Stability and Reactivity of Graphene-Templated Nanoclusters

Exploiting the versatility of the graphene/Ir(111) template, we performed a comparative study on arrays of various metallic nanoclusters. Using scanning tunneling microscopy and synchrotron-based high-resolution X-ray photoelectron spectroscopy, we investigated the size dependent stability of Pt, Ir, and Au nanoclusters against sintering upon gas exposure. These clusters display gross differences in their gas adsorption properties, as well as in their activity for the CO oxidation reaction

Colonization with multidrug resistant organisms determines the clinical course of patients with acute myeloid leukemia undergoing intensive induction chemotherapy.

IntroductionThe global spread of multidrug-resistant organisms (MDRO) complicates treatment and isolation measures in hospitals and has shown to increase mortality. Patients with disease- or therapy-related immunodeficiency are especially at risk for fatal infections caused by MDRO. The impact of MDRO colonization on the clinical course of AML patients undergoing intensive induction chemotherapy-a potentially curative but highly toxic treatment option-has not been systematically studied.Materials & methods312 AML patients undergoing intensive induction chemotherapy between 2007 and 2015 were examined for MDRO colonization. Patients with evidence for MDRO before or during the hospital stay of induction chemotherapy were defined as colonized, patients who never had a positive swab for MDRO were defined as noncolonized.ResultsOf 312 AML patients 90 were colonized and 130 were noncolonized. Colonized patients suffered from significantly more days with fever, spent more days on the intensive care unit and had a higher median C-reactive protein value during the hospital stay. These findings did not result in a prolonged length of hospital stay or an increased mortality rate for colonized patients. However, in a subgroup analysis, patients colonized with carbapenem-resistant enterobacteriaceae (CRE) had a significantly reduced 60- and 90-day, as well as 1- and 2-year survival rates when compared to noncolonized patients.ConclusionOur analysis highlights the importance of intensive MDRO screening especially in patients with febrile neutropenia since persisting fever can be a sign of MDRO-colonization. CRE-colonized patients require special surveillance, since they seem to be at risk for death

Colonization with multidrug resistant organisms determines the clinical course of patients with acute myeloid leukemia undergoing intensive induction chemotherapy

Introduction: The global spread of multidrug-resistant organisms (MDRO) complicates treatment and isolation measures in hospitals and has shown to increase mortality. Patients with disease- or therapy-related immunodeficiency are especially at risk for fatal infections caused by MDRO. The impact of MDRO colonization on the clinical course of AML patients undergoing intensive induction chemotherapy—a potentially curative but highly toxic treatment option—has not been systematically studied. Materials & methods: 312 AML patients undergoing intensive induction chemotherapy between 2007 and 2015 were examined for MDRO colonization. Patients with evidence for MDRO before or during the hospital stay of induction chemotherapy were defined as colonized, patients who never had a positive swab for MDRO were defined as noncolonized. Results: Of 312 AML patients 90 were colonized and 130 were noncolonized. Colonized patients suffered from significantly more days with fever, spent more days on the intensive care unit and had a higher median C-reactive protein value during the hospital stay. These findings did not result in a prolonged length of hospital stay or an increased mortality rate for colonized patients. However, in a subgroup analysis, patients colonized with carbapenem-resistant enterobacteriaceae (CRE) had a significantly reduced 60- and 90-day, as well as 1- and 2-year survival rates when compared to noncolonized patients. Conclusion: Our analysis highlights the importance of intensive MDRO screening especially in patients with febrile neutropenia since persisting fever can be a sign of MDRO-colonization. CRE-colonized patients require special surveillance, since they seem to be at risk for death

Application of Simulation Chambers to Investigate Interfacial Processes

Earlier chapters of this work have described procedures and protocols that are applicable to most chambers, this chapter has a slightly different focus; we predominantly consider multiphase processes where the applications are on phase transfer of chemical species rather than chemical reactions and the processes are generally occurring in highly specialized chambers. Three areas are described. Firstly, cloud formation processes; here, precise control of physical and thermodynamic properties is required to generate reproducible results. The second area examined is the air/sea interface, looking at the formation of aerosols from nonanoic acid as a surfactant with humic acid as a photosensitizer. The final apparatus described is the Roland von Glasow sea-ice chamber where a detailed protocol for the reproducible formation of sea-ice is given along with an outlook of future work. The systems studied in all three sections are characterized by difficulties in making detailed in situ observations in the real world, either due to the transitory nature of systems or the practical difficulties in accessing the systems. While these specialized simulation chambers may not perfectly reproduce conditions in the real world, the chambers do provide more facile opportunities for making extended and reproducible measurements to investigate fundamental physical and chemical processes, at significantly lower costs