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Background: Leukaemic patients receiving intensive chemotherapy and patients undergoing autologous stem-cell transplantation (ASCT) are routinely screened for oral foci of infection to reduce infectious complications that could occur during therapy. In this prospective study we assessed the effect of leaving chronic oral foci of infection untreated on the development of infectious complications in intensively treated haematological patients.Methods: We included and prospectively evaluated all intensively treated leukaemic patients and patients undergoing ASCT who were referred to our medical centre between September 2012 and May 2014, and who matched the inclusion/exclusion criteria. Acute oral foci of infection were removed before chemotherapy or ASCT, whereas chronic oral foci were left untreated.Results: In total 28 leukaemic and 35 ASCT patients were included. Acute oral foci of infection were found in 2 leukaemic (7%) and 2 ASCT patients (6%), and chronic oral foci of infection in 24 leukaemic (86%) and 22 ASCT patients (63%). Positive blood cultures with microorganisms potentially originating from the oral cavity occurred in 7 patients during treatment, but were uneventful on development of infectious complications.Conclusions: Our prospective study supports the hypothesis that chronic oral foci of infection can be left untreated as this does not increase infectious complications during intensive chemotherapy. [ABSTRACT FROM AUTHOR]

I n vitro and in vivo rehydration and germination in Cupressus arizonica pollen were examined using light and scanning electron microscopy. Shed pollen has 12.6% water content, which reduced to 8.2% after dispersal, and this latter pollen survived for some months at room temperature and for years at −10 °C. Rehydration requires breaking of the sporoderm walls and depends on the composition and pH of the rehydration medium. Acidity restrains the breakage, while alkalinity promotes it. Pollen division follows exine shedding and requires the persistence of the mucilaginous layer; hence, pH values countering these outcomes prevent division. Division results in a large and a small cell separated by a callosic wall. A pollen tube develops from the innermost intine of the large cell, which is callosic, and extends into the mucilaginous middle intine. The percentage germination never exceeded 17% in all tested media. In vivo, pollen rehydrates and casts off the exine in the micropylar drop. Drop withdrawal brings pollen to the apical nucellar cells that degenerate in the meantime, and it leaves a deposit on the surface of the micropylar canal. After contaction of the nucellar cells, the pollen flattens and its mucilaginous layer shrinks and disappears. This occurs simultaneously with sealing of the micropylar canal. During this time, pollen divides asymmetrically without the callosic wall, and the larger cell develops a tube in the interface with the nucellus. Only some pollen grains accomplish adhesion to the nucellus and germinate. The in vitro and in vivo developmental stages are discussed. [ABSTRACT FROM AUTHOR]

Saporins are enzymes belonging to the PNAG class (polynucleotide: adenosine glycosidase), plant enzymes commonly known as ribosome-inactivating proteins (RIP), as a result of their property of irreversibly damaging eukaryotic ribosomes. Direct imaging with tapping-mode atomic force microscopy (AFM) has been used to study pGEM-4Z plasmid DNA binding to the saporin-SO6 (isoform fromSaponaria officinalisseeds). Saporin wrapped the plasmidic DNA, and distribution of the enzyme molecules along the DNA chain was markedly variable; plasmid digested with saporin-SO6 appeared fragmented or topologically modified. The supercoiled DNA strands were cleaved, giving rise to a linearized form and to relaxed forms. Electrophoretic analysis of the effect of standard preparations of saporin-SO6 on pGEM-4S confirmed the presence of DNA strand-cleaving activity. [ABSTRACT FROM AUTHOR]

Objectives: In patients with invasive aspergillosis (IA), fungal cultures are mostly negative. Consequently, azole resistance often remains undetected. The AsperGenius® multiplex real-time PCR assay identifies clinically relevant Aspergillus species and four resistance-associated mutations (RAMs; TR34/L98H/T289A/Y121F) in the Cyp51A gene. This multicentre study evaluated the diagnostic performance of this assay on bronchoalveolar lavage (BAL) fluid and correlated the presence of RAMs with azole treatment failure and mortality.Methods: Stored BAL samples from patients with haematological diseases with suspected IA were used. BAL samples that were galactomannan/culture positive were considered positive controls for the presence of Aspergillus. Azole treatment failure and 6 week mortality were compared in patients with and without RAMs that had received ≥5 days of voriconazole monotherapy.Results: Two hundred and one patients each contributed one BAL sample, of which 88 were positive controls and 113 were negative controls. The optimal cycle threshold cut-off value for the Aspergillus species PCR was <38. With this cut-off, the PCR was positive in 74/88 positive controls. The sensitivity, specificity, positive predictive value and negative predictive value were 84%, 80%, 76% and 87%, respectively. 32/74 BAL samples were culture negative. Azole treatment failure was observed in 6/8 patients with a RAM compared with 12/45 patients without RAMs (P = 0.01). Six week mortality was 2.7 times higher in patients with RAMs (50.0% versus 18.6%; P = 0.07).Conclusions: The AsperGenius® assay had a good diagnostic performance on BAL and differentiated WT from Aspergillus fumigatus with RAMs, including in culture-negative BAL samples. Most importantly, detection of RAMs was associated with azole treatment failure. [ABSTRACT FROM AUTHOR]

An abstract of the article "Algorithm for empirical glycopeptide treatment in patients with hematologic malignancies and enterococcus faecium blood stream infection," by X. Zhou, M. Kerkhof, L. Span and colleagues, is presented.

In this paper a patient with a non-Hodgkin's lymphoma (NHL) and paraneoplastic pemphigus (PNP) is described. PNP is a very rare, painful mucocutaneous intraepithelial blistering disease associated with occult or confirmed malignancy. Patients with PNP show severe, progressive mucocutaneous disease with a high mortality rate, because of drug-induced infectious complications. The patients sometimes benefit from high doses of oral corticosteroids. However, pulse therapy with high doses of prednisolone (or dexamethasone) in combination with other immunosuppressants induces variable and inconstant results. Intravenous immunoglobulin (IVIg) has been applied in different cases of PNP with encouraging results. Plasmapheresis or plasma exchange (PE) in combination with corticosteroids and/or cyclophosphamide or azathioprine showed similar rapid and beneficial results in association with decreasing auto-antibody levels in this group of refractory pemphigus. Another interesting therapeutic option is rituximab, a chimeric monoclonal antibody directed against the CD20 antigen, which is found on the surface of normal and malignant B-lymphocytes. Administration of rituximab for patients with PNP in combination with follicular NHL is not always successful regarding oral lesions as we report in this case. PE leading to prompt depletion of autoreactive antibodies combined with immunosuppressants or synchronisation of PE with IVIg seems the best treatment modality for this refractory group, but the therapeutic value and appropriate timing of rituximab obviously deserve further evaluation in patients with low grade NHL and PNP. [ABSTRACT FROM AUTHOR]

Myelodysplastic syndromes (MDS) are highly proliferative bone marrow (BM) disorders where the primary lesion presumably affects a CD34+ early progenitor or stem cell. We investigated the proliferative characteristics of CD34+ cells of 33 untreated MDS patients (19 RA, 5 RARS, 7 RAEB, 2 RAEBt) and five patients with acute myeloid leukemia after MDS (sAML). All patients received a 1-h infusion of the thymidine analogue iodoor bromodeoxyuridine intravenously before a BM aspirate and biopsy was taken. A double-labeling immunohistochemistry technique by monoclonal anti-CD34 (QBend/10) and anti-IUdR/BrdU antibodies was developed and performed. By this technique we recognised CD34+ and CD34- cells actively engaged in DNA synthesis or not. As MDS evolves a significant increase occurred in the percentage of CD34+ cells of all myeloid cells (mean value: RA/RARS 1.67%; RAEB(t) 8.68%; sAML 23.83%) as well as in the percentage of proliferating CD34+ cells of all myeloid cells (RA/RARS 0.19%; RAEB(t) 0.43%; and sAML 3.30%). This was associated with a decreasing trend in the overall myeloid labeling index (LI: RA/RARS 25.8%, RAEB(t) 24.6% and sAML 21.5%). This decrease in overall myeloid LI is due to an exponential increase in the proportion of CD34+ cells of the proliferating compartment during MDS evolution (RA/RARS 0.35%, RAEB(t) 1.44% and sAML 11.98% of all S-phase cells). These CD34+ cells appeared to proliferate more slowly than their more mature CD34 negative counterparts, since we found a progressive increment in the mean total cell cycling time (Tc) of all myeloid cells during MDS progression (RA/RARS 39.8, RAEB(t) 45.2 and sAML 65.8 h). This study showed that during MDS evolution to sAML the CD34+ compartment develops a growth advantage leading to apparent expansion. [ABSTRACT FROM AUTHOR]