Distinct Communities of Poplar Endophytes on an Unpolluted and a Risk Element-Polluted Site and Their Plant Growth-Promoting Potential In Vitro.

Numerous studies demonstrated that endophytic microbes can promote plant growth and increase plant stress resistance. We aimed at isolating poplar endophytes able to increase their hosts' fitness both in nutrient-limited and polluted environments. To achieve this goal, endophytic bacteria and fungi were isolated from roots and leaves of hybrid poplars (Populus nigra × P. maximowiczii clone Max-4) on an unpolluted and a risk element-polluted site in the Czech Republic and subsequently screened by a number of in vitro tests. Bacterial communities at the unpolluted site were dominated by Gammaproteobacteria with Pseudomonas sp. as the prominent member of the class, followed by Bacilli with prevailing Bacillus sp., whereas Alphaproteobacteria, mostly Rhizobium sp., prevailed at the polluted site. The fungal endophytic community was dominated by Ascomycetes and highly distinct on both sites. Dothideomycetes, mostly Cladosporium, prevailed at the non-polluted site while unclassified Sordariomycetous fungi dominated at the polluted site. Species diversity of endophytes was higher at the unpolluted site. Many tested endophytic strains solubilized phosphate and produced siderophores, phytohormones, and antioxidants. Some strains also exhibited ACC-deaminase activity. Selected bacteria showed high tolerance and the ability to accumulate risk elements, making them promising candidates for use in inocula promoting biomass production and phytoremediation. Graphical Abstract ᅟ.

Low molecular weight heparins for thromboprophylaxis during induction chemotherapy in patients with multiple myeloma.

BACKGROUNDS: Patients with multiple myeloma have a high risk of venous thromboembolism (VTE), especially during the induction chemotherapy. The aim of our observational study was to determine the impact of prophylaxis with low molecular weight heparin (LMWH) on the incidence of thromboembolic complications. PATIENTS AND METHODS: We analyzed the incidence of thromboembolic events in 258 patients treated with induction chemotherapy containing vincristin, doxorubicin or idarubicin, and dexamethasone, followed by stimulation chemotherapy with cyclophosphamide and G-CSF, and high-dose chemotherapy with melphalan. Two groups of these patients were compared based on the practice of thromboprophylaxis. Patients in the first group (Control, n = 140) were either not treated or treated with a short duration of anticoagulation therapy while the patients in the second group (Prophylactic, n = 118) underwent standard prophylaxis with LMWH throughout the entire period of induction chemotherapy. A total of 102 patients were selected for a close monitoring of the prophylactic effect of different LMWH doses and to be compared to patients without treatment. RESULTS: Standard prophylaxis with LMWH significantly (p < 0.007) lowered a risk of VTE when compared to patients without such prophylaxis (3.4% versus 12.9%, respectively). Furthermore, analysis of the subgroup of 102 patients revealed that higher LMWH doses (> 70 IU/kg per day) achieved full prophylaxis in 28 patients while lower doses were less effective leading to DVT in 3 (7.7%) out of 39 patients. In contrast, VTE was diagnosed in 5 (14.3%) out of 35 patients without any LMWH prophylaxis. CONCLUSION: Prophylaxis with LMWH leads to a significant reduction of the risk of thromboembolic complications during the induction chemotherapy in patients suffering from MM. The prophylactic effect of LMWH is dose-dependent.

Bacterial and fungal endophyte communities in healthy and diseased oilseed rape and their potential for biocontrol of Sclerotinia and Phoma disease.

Phoma stem canker (caused by the ascomycetes Leptosphaeria maculans and Leptosphaeria biglobosa) is an important disease of oilseed rape. Its effect on endophyte communities in roots and shoots and the potential of endophytes to promote growth and control diseases of oilseed rape (OSR) was investigated. Phoma stem canker had a large effect especially on fungal but also on bacterial endophyte communities. Dominant bacterial genera were Pseudomonas, followed by Enterobacter, Serratia, Stenotrophomonas, Bacillus and Staphylococcus. Achromobacter, Pectobacter and Sphingobacterium were isolated only from diseased plants, though in very small numbers. The fungal genera Cladosporium, Botrytis and Torula were dominant in healthy plants whereas Alternaria, Fusarium and Basidiomycetes (Vishniacozyma, Holtermaniella, Bjerkandera/Thanatephorus) occurred exclusively in diseased plants. Remarkably, Leptosphaeria biglobosa could be isolated in large numbers from shoots of both healthy and diseased plants. Plant growth promoting properties (antioxidative activity, P-solubilisation, production of phytohormones and siderophores) were widespread in OSR endophytes. Although none of the tested bacterial endophytes (Achromobacter, Enterobacter, Pseudomonas, Serratia and Stenotrophomonas) promoted growth of oilseed rape under P-limiting conditions or controlled Phoma disease on oilseed rape cotyledons, they significantly reduced incidence of Sclerotinia disease. In the field, a combined inoculum consisting of Achromobacter piechaudii, two pseudomonads and Stenotrophomonas rhizophila tendencially increased OSR yield and reduced Phoma stem canker.