Expansion and Conservation of Biosynthetic Gene Clusters in Pathogenic Pyrenophora spp

Pyrenophora is a fungal genus responsible for a number of major cereal diseases. Although fungi produce many specialised or secondary metabolites for defence and interacting with the surrounding environment, the repertoire of specialised metabolites (SM) within Pyrenophora pathogenic species remains mostly uncharted. In this study, an in-depth comparative analysis of the P. teres f. teres, P teres f. maculata and P. tritici-repentis potential to produce SMs, based on in silico predicted biosynthetic gene clusters (BGCs), was conducted using genome assemblies from PacBio DNA reads. Conservation of BGCs between the Pyrenophora species included type I polyketide synthases, terpene synthases and the first reporting of a type III polyketide synthase in P teres f. maculata. P. teres isolates exhibited substantial expansion of non-ribosomal peptide synthases relative to P. tritici-repentis, hallmarked by the presence of tailoring cis-acting nitrogen methyltransferase domains. P. teres isolates also possessed unique non-ribosomal peptide synthase (NRPS)-indole and indole BGCs, while a P. tritici-repentis phytotoxin BGC for triticone production was absent in P. teres. These differences highlight diversification between the pathogens that reflects their different evolutionary histories, host adaption and lifestyles.

Cost of care for prostate cancer patients: An observational cohort study comparing clinical trials to standard care

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Background: Monetary support of clinical trials is a fundamental necessity for improving treatment and prevention methods; however, current economic data pertaining to the per-patient costs of treating prostate cancer are limited. A concurrent lack of certainty regarding the cost requirements of standard care patients makes it difficult for healthcare professionals and policy makers to generate informed decisions regarding budgets and funding needs. Prostate cancer clinical trials are facing a national funding crisis due to the perception that patients enrolled in clinical trials consume more resources than patients receiving standard care.

Methods: A retrospective observational cohort study was conducted to examine the costs incurred by prostate cancer patients at the Tom Baker Cancer Center over one year. Costs for 36 patients enrolled in one of nine cancer trials were compared with costs for 36 matched control subjects who received standard care. Resource utilization was tracked using medical charts and quantified by prices listed in the TBCC's 2009 Clinical Trials Budget template.

Results: No evidence was found to support a difference in overall resource utilization between clinical trial patients and standard of care patients (Paired two-tailed t- test, N= 36, p =0.90). There was, however, variability in the types of resources used by each patient population, indicating that, while trial patients may take up significantly more clinic time (p =0.04), undergo more tests and procedures (p < 0.001) and require more diagnostic imaging (p = 0.01), standard care patients are more likely to receive costly interventions such as radiation therapy (p =0.06). Pharmaceutical costs have not yet been included in the analysis and could drastically alter the final results.

Conclusions: This study revealed differences in the cost distribution of clinical trials patients versus standard of care patients, which could be used by administrators to improve budgeting and time allocation. The lack of difference in overall cost may be helpful to research advocates attempting to encourage centers to take on more trials. Further analysis is required before definitive conclusions can be drawn.

No significant financial relationships to disclose.

Racial differences in acute toxicities of FEC 100 chemotherapy in patients with breast cancer

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Background: Racial disparities in breast cancer outcomes are attributed to differences in baseline tumor characteristics, stage, and socioeconomic factors. However, little is known about racial differences in treatment-related toxicities. We hypothesized that racial and ethnic differences result in differential tolerance to chemotherapy and possibly compromise to the dose intensity of adjuvant/neoadjuvant chemotherapy. Methods: Data was collected from 4 international collaborating centers (University of Miami, JBCRG (Japan Breast Cancer Research Group), University of Hong Kong, and Tom Baker Cancer Center) at which patients of different ethnic background have been treated for non metastatic breast cancer with same adjuvant or neoadjuvant chemotherapy of FEC 100: fluorouracil 500 mg/m2, epirubicin 100 mg/m2, and cyclophosphamide 100 mg/m2). Racial/ethnic differences in toxicities were assessed by first episode of grade 2 or higher toxicity. Analysis of data was performed at the University of Miami. Results: Treatment-related toxicities are compared according to four race/ethnicity groups (120 Caucasian from USA and Canada (C), 16 African American (AA) from USA and Canada, 141 Japanese Asian (JA), and 23 Asian from Hong Kong (HKA)) (Table). JA and HKA had a significant higher rate of grade 3 or higher toxicity compared with C or AA women; 65%, 61%, 28%, and 31% respectively. However, there were no significant differences in chemotherapy dose intensity or density across the 4 race/ethnicity groups. Conclusions: This unique study noted racial differences in acute toxicity in women with breast cancer who were treated with FEC 100 chemotherapy. However, there are several limitations including the retrospective nature of our study, differences in practice across four countries, and different number of patients available for comparison. This study is ongoing and further statistical analyses are planned when a larger sample size is reached.

[Table: see text]

No significant financial relationships to disclose.

The role of depletion of dimethyl sulfoxide before autografting: on hematologic recovery, side effects, and toxicity

Cryopreservation of stem cells after collection from peripheral blood or bone marrow for autologous transplantation necessitates protection with dimethyl sulfoxide (DMSO). Unfortunately, DMSO, when infused with the thawed cell suspension, may induce serious complications and side effects. To assess whether depletion of DMSO before autografting affects safety and efficacy, 56 consenting consecutive patients treated with high-dose chemotherapy and autologous blood stem cell transplantation were assigned to obtain either an untreated or DMSO-depleted autograft. On the day of transplantation, the cryopreserved cells were thawed and infused to the patient either immediately or after washing 3 times in normal saline supplemented with 6% anticoagulant citrate dextrose solution. Cell count with viability, clonogenic assay, and phenotyping were performed before and after thawing and after washing. Hematologic recovery, side effects, and complications were recorded. The in vitro and clinical data on 56 patients show that the depletion of DMSO in vitro before autografting does not induce a significant loss of cell number, viability, colony-forming unit-granulocyte-macrophage activity, or number of CD34(+) cells. Furthermore, it leads to a safe and sustained engraftment. The complications and side effects, as recorded by continuous monitoring, were substantially less; however, the procedure takes 3 to 4 hours of laboratory work per patient.

Micrometastases in apheresis products predict shorter progression-free and overall survival in patients with breast cancer undergoing high-dose chemotherapy (HDCT) and autologous blood stem cell transplantation (ABSCT)

The presence of cancer cells in autografts of breast cancer patients has been described to have prognostic value or directly lead to relapse. Previously, we demonstrated that apheresis products (APs) collected after induction chemotherapy have a significantly lower likelihood of tumor cell contamination. Here, we examine the prognostic value of micrometastases in autografts. Data from 83 patients with breast cancer treated with autologous blood stem cell transplantation were analyzed. Pan-cytokeratin-FITC conjugated antibodies were used to detect contaminating breast cancer cells in the APs. Progression and survival data analyzed on the basis of three or fewer cancer cells showed no significant differences in outcomes. Of the 83 patients, 11 had more than three cancer cells detectable in their APs. In total, 72 patients were shown to have less than three cells detectable. When patients with more than three cells were compared to patients with 0-3, we found statistically significant differences in progression-free survival. We also found a significant difference in overall survival (OS) between the two groups. No difference was observed in OS since the time of diagnosis. We conclude that patients with more than three contaminating cells in their APs have micrometastases and represent a poor prognosis group.

Storage of blood for in vitro generation of dendritic cells

BACKGROUND

Since the development of techniques to cultivate DC from peripheral blood, there has been a great deal of interest in the use of these cells in immunotherapeutic strategies. In a clinical setting, delays often occur between when blood is drawn and when it is processed. We therefore investigated the effect of overnight storage on the yield, morphology and phenotype of DC cultured from the peripheral blood of healthy volunteers.

METHOD

Blood was processed either immediately, or after storage for 24 h in the fridge (4 degrees C) or at room temperature (RT, 20 degrees C). Samples were compared for starting cell number, DC yield and characteristics (morphology and phenotype).

RESULTS

The number of PBMC that could be obtained was significantly lower from the refrigerated samples compared with both the freshly processed sample and that stored at RT. Samples processed after overnight storage at RT yielded cells morphologically identical to DC cultured from freshly processed samples. Only when samples were both stored and processed cold did the cultured cells not have typical DC morphology. DC cultured from the refrigerated samples showed a significant reduction in MHC II expression compared with samples processed fresh or stored at RT. This expression increased slightly when the sample was first warmed. Total DC yield and the percentage yield of cultured DC was not significantly different for any of the groups.

DISCUSSION

We conclude that, if immediate processing of blood for in vitro generation of DC is not possible, samples should be stored at room temperature (approximately 20 degrees C).

Generation of dendritic cells: role of cytokines and potential clinical applications

Over the last decade there has been great interest in generating populations of antigen presenting cells (APC), which can be exploited to improve immune responses to a variety of diseases including malignancies. Dendritic cells (DC) are an APC population that are easily generated ex vivo using a variety of cytokines. Cytokines can also be used to further manipulate these cells in maturation and function. The following discussion will provide an overview of dendritic cell isolation and generation with a focus on the role cytokines play in this process.

Effects of cytokines on the culture and differentiation of dendritic cells in vitro

The ability to culture dendritic cells (DC) in vitro has been integral to the dramatic increase in research in the area of immunotherapy. Over time, a number of methods for generating these cells have been developed. This article will provide an overview of the isolation and generation of DC and will give a detailed description of the role specific cytokines play in this process from the mobilization of precursors to the final maturation of DC.

Japanese Aedes albopictus among four mosquito species reaching New Zealand in used tires

Since a 1988-89 survey of northern New Zealand revealed no additions to the known mosquito fauna, this country's used tire importations have much increased. Relevant entomological quarantine was thus monitored in a November 1992-January 1993 Auckland project, during which almost 1/3 of 8,549 casings from Japan proved wet on inspection. In this study and at 2 South Island ports afterwards, 5 vessels from Japan and one from Australia were found to have brought in mosquito-infested used tires. Live Aedes albopictus (all larval instars, pupae, and adults) and Aedes japonicus, and dead Tripteroides bambusa were discovered in shipments from Japan (3 interceptions each in the first 2 cases, and one in the 3rd). Live Tripteroides tasmaniensis were recorded from the Australian cargo. One of the Ae. albopictus arrivals was followed by an apprehended introduction at an Auckland importer's premises.