Vaccination with DNA plasmids expressing Gn coupled to C3d or alphavirus replicons expressing Gn protects mice against rift valley fever virus

Background: Rift Valley fever (RVF) is an arthropod-borne viral zoonosis. Rift Valley fever virus (RVFV) is an important biological threat with the potential to spread to new susceptible areas. In addition, it is a potential biowarfare agent. Methodology/Principal Findings: We developed two potential vaccines, DNA plasmids and alphavirus replicons, expressing the Gn glycoprotein of RVFV alone or fused to three copies of complement protein, C3d. Each vaccine was administered to mice in an all DNA, all replicon, or a DNA prime/replicon boost strategy and both the humoral and cellular responses were assessed. DNA plasmids expressing Gn-C3d and alphavirus replicons expressing Gn elicited high titer neutralizing antibodies that were similar to titers elicited by the live-attenuated MP12 virus. Mice vaccinated with an inactivated form of MP12 did elicit high titer antibodies, but these antibodies were unable to neutralize RVFV infection. However, only vaccine strategies incorporating alphavirus replicons elicited cellular responses to Gn. Both vaccines strategies completely prevented weight loss and morbidity and protected against lethal RVFV challenge. Passive transfer of antisera from vaccinated mice into naïve mice showed that both DNA plasmids expressing Gn-C3d and alphavirus replicons expressing Gn elicited antibodies that protected mice as well as sera from mice immunized with MP12. Conclusion/Significance: These results show that both DNA plasmids expressing Gn-C3d and alphavirus replicons expressing Gn administered alone or in a DNA prime/replicon boost strategy are effective RVFV vaccines. These vaccine strategies provide safer alternatives to using live-attenuated RVFV vaccines for human use. © 2010 Bhardwaj et al

Difficulties in recruitment for a randomized controlled trial involving hysterosalpingography

BACKGROUND: The usefulness of hysterosalpingography (HSG) as routine investigation in the fertility work-up prior to laparoscopy and dye had been assessed in a randomized controlled trial. Recruiting subjects to the study was more difficult than anticipated. The objective of this study was to explore possible reasons for non-participation in the trial. METHODS: All newly referred subfertile women admitted to the Reproductive Medicine Clinic of Leiden University Medical Centre between 1 April 1997 and 31 December 1999, were eligible for the study. The reasons for non-participation were evaluated by scrutinizing the medical records. RESULTS: Out of 759 women, a total of 127 (17%) agreed to participate in the trial. The most important reason for non-participation was because of exclusion criteria (73%). Other reasons were inattentive clinicians (3%) and patient-associated reasons (24%). Patient refusal and indecisiveness to enroll in the study were the most common patient-associated reasons. The most frequently stated reason for trial refusal was reluctance to undergo laparoscopy and dye mainly due to issues related to anesthesia and scheduling of procedure. CONCLUSION: Almost three-quarters of recruitment difficulties in this study were due to unavoidable reasons. To overcome the remaining avoidable reasons for non-participation, attention should be paid to appropriate instruction of the study protocol to the participating doctors and to provide adequate information, in layman's terms, to the patients. Reminding patients by notes or telephone calls for attending the clinic are helpful. It may be contingent upon tracing the reasons of clinicians and patients for non-participation to improve enrollment during a trial

Genome-Wide Epigenetic and Transcriptomic Characterization of Human-Induced Pluripotent Stem Cell-Derived Intestinal Epithelial Organoids.

Human induced pluripotent stem cells (hiPSC) have been used to generate intestinal organoids that mimic key intestinal properties without the requirement for invasive procedures to obtain human tissues. The main protocols that have been described result in gut organoids that contain both intestinal epithelium as well as mesenchymal cells (2, 3). We have previously reported on human iPSC-derived intestinal organoids that can be propagated in long-term culture which contain solely epithelial cells (4–6). A pure epithelial model offers unique opportunities to study epithelial cell intrinsic and cell type specific mechanisms. Among these cellular processes are epigenetic mechanisms such as DNA methylation, which acts as a key regulator of intestinal epithelial development and regional identity (1, 7). The purpose of this study was to characterise iPSC-derived human intestinal epithelial organoids (iPSCo) by comparing these cultures with primary purified intestinal epithelial cells (IEC).JK was supported by Crohn’s & Colitis UK and Crohn’s in Childhood Research association (CICRA). GD and JF received core support from the Wellcome Trust. We would also like to thank the WTSI Core Scientific Operations team for conducting Illumina transcriptome sequencing. RNA-Sequencing was funded by the Wellcome Trust [206194]. LV is funded by the European Research Council advanced grant New-Chol (ERC: 741707), Cambridge University Hospitals NIHR Biomedical Research Center, core support from the Wellcome Trust and MRC to the Cambridge Stem Cell Institute (PSAG028) and the EU grant INTENS. AR is supported by the Wellcome Trust Interdisciplinary Programme in Translational Medicine and Therapeutics (TMAT) (100138/B/12/Z)

Single-Cell Sequencing of Developing Human Gut Reveals Transcriptional Links to Childhood Crohn's Disease.

Human gut development requires the orchestrated interaction of differentiating cell types. Here, we generate an in-depth single-cell map of the developing human intestine at 6-10 weeks post-conception. Our analysis reveals the transcriptional profile of cycling epithelial precursor cells; distinct from LGR5-expressing cells. We propose that these cells may contribute to differentiated cell subsets via the generation of LGR5-expressing stem cells and receive signals from surrounding mesenchymal cells. Furthermore, we draw parallels between the transcriptomes of ex vivo tissues and in vitro fetal organoids, revealing the maturation of organoid cultures in a dish. Lastly, we compare scRNA-seq profiles from pediatric Crohn's disease epithelium alongside matched healthy controls to reveal disease-associated changes in the epithelial composition. Contrasting these with the fetal profiles reveals the re-activation of fetal transcription factors in Crohn's disease. Our study provides a resource available at www.gutcellatlas.org, and underscores the importance of unraveling fetal development in understanding disease

Impact of generic alendronate cost on the cost-effectiveness of osteoporosis screening and treatment

Introduction: Since alendronate became available in generic form in the Unites States in 2008, its price has been decreasing. The objective of this study was to investigate the impact of alendronate cost on the cost-effectiveness of osteoporosis screening and treatment in postmenopausal women. Methods: Microsimulation cost-effectiveness model of osteoporosis screening and treatment for U.S. women age 65 and older. We assumed screening initiation at age 65 with central dual-energy x-ray absorptiometry (DXA), and alendronate treatment for individuals with osteoporosis; with a comparator of "no screening" and treatment only after fracture occurrence. We evaluated annual alendronate costs of $20 through$800; outcome measures included fractures; nursing home admission; medication adverse events; death; costs; quality-adjusted life-years (QALYs); and incremental cost-effectiveness ratios (ICERs) in 2010 U.S. dollars per QALY gained. A lifetime time horizon was used, and direct costs were included. Base-case and sensitivity analyses were performed. Results: Base-case analysis results showed that at annual alendronate costs of $200 or less, osteoporosis screening followed by treatment was cost-saving, resulting in lower total costs than no screening as well as more QALYs (10.6 additional quality-adjusted life-days). When assuming alendronate costs of$400 through $800, screening and treatment resulted in greater lifetime costs than no screening but was highly cost-effective, with ICERs ranging from$714 per QALY gained through $13,902 per QALY gained. Probabilistic sensitivity analyses revealed that the cost-effectiveness of osteoporosis screening followed by alendronate treatment was robust to joint input parameter estimate variation at a willingness-to-pay threshold of$50,000/QALY at all alendronate costs evaluated. Conclusions: Osteoporosis screening followed by alendronate treatment is effective and highly cost-effective for postmenopausal women across a range of alendronate costs, and may be cost-saving at annual alendronate costs of $200 or less. © 2012 Nayak et al

Fixation of osteochondral fragments in the human knee using Meniscus Arrows®

The aim of this study is to compare the hold in bone of Meniscus Arrows® and Smart Nails®, followed by the report of the results of the clinical application of Meniscus Arrows® as fixation devices. First, pull-out tests were performed to analyse the holdfast of both nails in bone. Statistical analysis showed no significant difference; therefore, the thinner Meniscus Arrow® was chosen as fixation device in the patient series of two patients with a symptomatic Osteochondritis dissecans fragment and three patients with an osteochondral fracture of a femur condyle. The cartilage margins were glued with Tissuecoll®. All fragments consolidated. Second look arthroscopy in three patients showed fixed fragments with stable, congruent cartilage edges. At an average follow-up period of 5 years no pain, effusion, locking, restricted range of motion or signs of osteoarthritis were reported. Based on the results of the pull-out tests and available clinical studies, Meniscus Arrows® and Smart Nails® are both likely to perform adequately as fixation devices in the treatment of Osteochondritis dissecans and osteochondral fractures in the knee. They both provide the advantage of one stage surgery. However, based on their smaller diameter, the Meniscus Arrows® should be preferred for this indication