Direct maldi-tof mass spectrometry assay of blood culture broths for rapid identification of Candida species causing bloodstream infections: an observational study in two large microbiology laboratories

We evaluated the reliability of the Bruker Daltonik's MALDI Biotyper system in species-level identification of yeasts directly from blood culture bottles. Identification results were concordant with those of the conventional culture-based method for 95.9% of Candida albicans (187/195) and 86.5% of non-albicans Candida species (128/148). Results were available in 30 min (median), suggesting that this approach is a reliable, time-saving tool for routine identification of Candida species causing bloodstream infection.     

Attenuated Salmonella enterica serovar Typhimurium lacking the ZnuABC transporter: An efficacious orally-administered mucosal vaccine against salmonellosis in pigs

We have recently demonstrated that an attenuated strain of Salmonella enterica serovar Typhimurium unable to synthesize the zinc transporter ZnuABC (S. Typhimurium ΔznuABC), is able to protect mice against systemic and enteric salmonellosis and is safe in pigs. Here, we have tested the protective effects of S. Typhimurium ΔznuABC in pigs. Resistance to challenge with the fully virulent strain S. Typhimurium ATCC 14028 was assessed in animals vaccinated with S. Typhimurium ΔznuABC (two dosages tested), in controls vaccinated with a formalin-inactivated virulent strain and in unvaccinated controls. Clinical signs of salmonellosis, faecal shedding and bacterial colonization of organs were used to assess vaccine-induced protection. After the challenge, pigs vaccinated with the attenuated S. Typhimurium ΔznuABC strain did not display clinical signs of salmonellosis (fever or diarrhoea). The vaccine also reduced intestinal tract colonization and faecal shedding of the fully virulent Salmonella strain, as compared to control groups. S. Typhimurium ΔznuABC represents a promising candidate vaccine against salmonellosis in pigs.     

Gemcitabine and carboplatin for pretreated metastatic breast cancer: the predictive value of immunohistochemically defined subtypes

Background

We evaluated the efficacy of gemcitabine and carboplatin for patients affected by pretreated metastatic breast cancer. A subgroup analysis was performed to evaluate the predictive value of immunohistochemically defined breast cancer subtypes.

Methods

We included human epidermal growth factor 2 (HER-2) negative metastatic breast cancer resistant to previous anthracycline-based and taxane-based chemotherapy, and HER-2 positive metastatic breast cancer with at least two progressions of disease during protracted trastuzumab-based therapy. Treatment consisted of gemcitabine (1000 mg/m² intravenous (iv) on days 1 and 8) and carboplatin (area under the curve 5 iv on day 1) applied every 3 weeks.

Results

Forty-two patients were registered. Disease control was 58%, with a median time-to-progression (TTP) of 7 months (range 1–12) and a median overall survival of 10.5 months (range 1–34). Patients were grouped as triple negative (ER and PR negative, HER-2 negative), HER-2 (HER-2 positive, ER and PR negative), luminal B (ER and/or PR positive and either HER-2 positive and/or high Ki67), and luminal A (ER and/or PR positive and HER-2 negative and low Ki67). For luminal A patients, disease control was lower (luminal A 34 vs. others 67%; P = 0.02), TTP was shorter (luminal A 2.4 months vs. others 6.3 months, P = 0.015), and overall survival was shorter (luminal A 7.5 months vs. others 11.7 months, P = 0.034) than for other subtypes.

Conclusions

Gemcitabine and carboplatin are effective for pretreated patients with metastatic breast cancer. Luminal A subtype seems to fare poorly compared with other subtypes. Specific difference in gene expression might account for the different outcome.     

Importance of Different Types of Prior Knowledge in Selecting Genome‐Wide Findings for Follow‐Up

Biological plausibility and other prior information could help select genome‐wide association (GWA) findings for further follow‐up, but there is no consensus on which types of knowledge should be considered or how to weight them. We used experts’ opinions and empirical evidence to estimate the relative importance of 15 types of information at the single‐nucleotide polymorphism (SNP) and gene levels. Opinions were elicited from 10 experts using a two‐round Delphi survey. Empirical evidence was obtained by comparing the frequency of each type of characteristic in SNPs established as being associated with seven disease traits through GWA meta‐analysis and independent replication, with the corresponding frequency in a randomly selected set of SNPs. SNP and gene characteristics were retrieved using a specially developed bioinformatics tool. Both the expert and the empirical evidence rated previous association in a meta‐analysis or more than one study as conferring the highest relative probability of true association, whereas previous association in a single study ranked much lower. High relative probabilities were also observed for location in a functional protein domain, although location in a region evolutionarily conserved in vertebrates was ranked high by the data but not by the experts. Our empirical evidence did not support the importance attributed by the experts to whether the gene encodes a protein in a pathway or shows interactions relevant to the trait. Our findings provide insight into the selection and weighting of different types of knowledge in SNP or gene prioritization, and point to areas requiring further research.     

Corrigendum

Givinostat, a histone‐deacetylase inhibitor (HDACi), inhibits proliferation of cells bearing the JAK2 V617F mutation and has shown significant activity with good tolerability in patients with chronic myeloproliferative neoplasms (MPN). In this multicentre, open‐label, phase II study, 44 patients with polycythaemia vera (PV), unresponsive to the maximum tolerated doses (MTD) of hydroxycarbamide (HC), were treated with Givinostat (50 or 100 mg/d) in combination with MTD of HC. The European LeukaemiaNet response criteria were used to assess the primary endpoint after 12 weeks of treatment. Complete or partial response was observed in 55% and 50% of patients receiving 50 or 100 mg of Givinostat, respectively. Control of pruritus was observed in 64% and 67% of patients in the 50 and 100 mg groups, respectively. The combination of Givinostat and HC was well tolerated: eight patients (18%) discontinued, four in each treatment arm; grade 3 adverse events were reported in one patient (4·5%) in each treatment arm. The combined use of Givinostat and HC was safe and clinically effective in HC‐unresponsive PV patients.     

Preparation and characterization of novel poly(ethylene glycol) paclitaxel derivatives

Paclitaxel has been found to be very effective against several human cancers; one of the major problems with its use is its poor solubility, which makes necessary its solubilization with excipients that can determine allergic reactions often severe. The aim of this study is to develop highly water-soluble prodrugs of paclitaxel. For this purpose we prepared a series of new paclitaxel–poly(ethylene glycol) (PEG) conjugates that were characterized and evaluated for their in vitro stability and cytotoxicity. In particular, in order to modulate the release of paclitaxel from prodrugs, we prepared different compounds introducing PEG in the drug C2′ and/or C7 positions via ester or carbamate linkage. The conjugates were obtained in high purity and good yield. The carbamate prodrugs were highly stable in different media, while the compounds obtained linking PEG at C2′ position through an ester bond showed lower stability. Finally, the cytotoxic activity of the conjugates was evaluated on two cancer cell lines and the results showed that all the derivatives had a reduced cytotoxicity compared to that of paclitaxel.     

Impact of donor-specific anti-HLA antibodies on graft failure and survival after reduced intensity conditioning-unrelated cord blood transplantation: a Eurocord,Société Francophone d’Histocompatibilité et d’Immunogénétique (SFHI) and Société Fran?aise de Greffe de Moelle et de Thérapie Cellulaire (SFGM-TC) analysis

Graft failure is a major complication after unrelated cord blood transplantation. Presence of HLA-antibodies before cord blood transplantation may impact graft failure. To analyze the effect of anti-HLA antibodies on unrelated cord blood transplantation outcomes, we analyzed 294 unrelated cord blood transplant recipients after reduced intensity conditioning regimen. The majority of the patients (82%) were transplanted for malignancies, 60% with double-unrelated cord blood transplant, 63% were HLA mismatched. Retrospectively, pre-unrelated cord blood transplant serum was tested for HLA-Ab using Luminex™ platform. Results were interpreted as mean fluorescence intensity (MFI) against donor-specific mismatch. Among 62 recipients (23%) who had anti-HLA antibodies before unrelated cord blood transplant, 14 patients had donor specific anti-HLA antibodies (DSA) (7 were donor-specific anti-HLA antibodies for single unrelated cord blood transplant and 7 for double unrelated cord blood transplant). Donor specific anti-HLA antibodies threshold ranged from 1620–17629 of mean fluorescence intensity (MFI). Cumulative incidence of Day-60 neutrophil engraftment was 76%: 44% for recipients with donor specific anti-HLA antibodies and 81% in those without donor specific anti-HLA antibodies (P=0.006). The cumulative incidence of 1-year transplant related mortality was 46% in patients with donor specific anti-HLA antibodies and 32% in those without antibodies (P=0.06). The presence of donor specific anti-HLA antibodies was associated with a trend for decreased survival rate (42% vs. 29%; P=0.07). Donor specific anti-HLA antibody in recipients of unrelated cord blood transplant is associated with graft failure and decreased survival. Patient’s screening for donor specific anti-HLA antibodies before unrelated cord blood transplantation is recommended before choosing an HLA mismatched cord blood unit. Whenever possible it is important to avoid selecting a unit for which the patient has donor specific anti-HLA antibodies.