Fluorescence in situ hybridization analysis of two blastomeres from day 3 frozen-thawed embryos followed by analysis of the remaining embryo on day 5

BACKGROUND: Chromosomal mosaicism in human embryos may give rise to false positive or false negative results in preimplantation genetic diagnosis for aneuploidy screening (PGD-AS). Therefore, we have investigated whether the results obtained from a 2-cell biopsy of frozen-thawed embryos and fluorescence in situ hybridization (FISH) analysis are representative for the chromosome constitution of the remaining embryo on day 5. METHODS: Cryopreserved day 3 embryos were thawed and from surviving embryos two blastomeres were biopsied. FISH analysis was performed for chromosomes 1, 7, 13, 15, 16, 18, 21, 22, X and Y. After biopsy, the embryos were cultured until day 5 and further analysed using the same probe panels. RESULTS: In all, 17 embryos were available with a diagnosis based on two blastomeres on day 3 and confirmatory studies on day 5. In 10 of these 17 cases the initial diagnosis could be confirmed. However, in only six cases cytogenetic results were concordant. Besides the 10 cases with a 'correct' diagnosis, there were six false positive results and one false negative, all involving mosaicism. CONCLUSIONS: Investigating the chromosomal constitution of two blastomere nuclei offers a good opportunity to study the incidence of chromosomal mosaicism in early embryo development. The confirmation rate of the results obtained on day 3 depends on the interpretation and is higher when considered from a clinical than from a cytogenetic point of view.     

The Carbomer-Lecithin Adjuvant Adjuplex Has Potent Immunoactivating Properties and Elicits Protective Adaptive Immunity against Influenza Virus Challenge in Mice

The continued discovery and development of adjuvants for vaccine formulation are important to safely increase potency and/or reduce the antigen doses of existing vaccines and tailor the adaptive immune response to newly developed vaccines. Adjuplex is a novel adjuvant platform based on a purified lecithin and carbomer homopolymer. Here, we analyzed the adjuvant activity of Adjuplex in mice for the soluble hemagglutinin (HA) glycoprotein of influenza A virus. The titration of Adjuplex revealed an optimal dose of 1% for immunogenicity, eliciting high titers of HA-specific IgG but inducing no significant weight loss. At this dose, Adjuplex completely protected mice from an otherwise lethal influenza virus challenge and was at least as effective as the adjuvants monophosphoryl lipid A (MPL) and alum in preventing disease. Adjuplex elicited balanced Th1-/Th2-type immune responses with accompanying cytokines and triggered antigen-specific CD8⁺ T-cell proliferation. The use of the peritoneal inflammation model revealed that Adjuplex recruited dendritic cells (DCs), monocytes, and neutrophils in the context of innate cytokine and chemokine secretion. Adjuplex neither triggered classical maturation of DCs nor activated a pathogen recognition receptor (PRR)-expressing NF-κB reporter cell line, suggesting a mechanism of action different from that reported for classical pathogen-associated molecular pattern (PAMP)-activated innate immunity. Taken together, these data reveal Adjuplex to be a potent and well-tolerated adjuvant with application for subunit vaccines.     

Glycan-Based Near-infrared Fluorescent (NIRF) Imaging of Gastrointestinal Tumors: a Preclinical Proof-of-Concept In Vivo Study

Molecular Imaging and Biology - Aberrantly expressed glycans in cancer are of particular interest for tumor targeting. This proof-of-concept in vivo study aims to validate the use of aberrant Lewis...     

In vivo antinuclear antibody of the skin: diagnostic significance and association with selective antinuclear antibodies.

Immunofluorescence microscopy of the skin has disclosed antibodies bound to epidermal cell nuclei in several connective tissue disorders. To establish the diagnostic potential of this phenomenon the results of immunofluorescence microscopy of biopsy specimens from 1651 subjects with various diseases and from 315 patients with systemic connective tissue disorders and related diseases were reviewed. It was found that the predictive value of the phenomenon for the presence of a systemic connective tissue disorder was, in general, 88%. Except for the homogeneous and thready patterns, which seldom appear, but are specific for SLE, in vivo antinuclear antibody (ANA) does not discriminate better between the various disorders than do serum antibodies. The presence of in vivo ANA in the skin was related to serum antibodies against non-histone nucleoproteins, but not to anti-dsDNA antibodies. Combined with the finding that antibodies against non-histone nucleoproteins can bind on the surface of human keratinocytes, this suggests that ANA of the skin occurs in vivo.     

Joint models for longitudinal and time-to-event data in a case-cohort design

Studies with longitudinal measurements are common in clinical research. Particular interest lies in studies where the repeated measurements are used to predict a time-to-event outcome, such as mortality, in a dynamic manner. If event rates in a study are low, however, and most information is to be expected from the patients experiencing the study endpoint, it may be more cost efficient to only use a subset of the data. One way of achieving this is by applying a case-cohort design, which selects all cases and only a random samples of the noncases. In the standard way of analyzing data in a case-cohort design, the noncases who were not selected are completely excluded from analysis; however, the overrepresentation of the cases will lead to bias. We propose to include survival information of all patients from the cohort in the analysis. We approach the fact that we do not have longitudinal information for a subset of the patients as a missing data problem and argue that the missingness mechanism is missing at random. Hence, results obtained from an appropriate model, such as a joint model, should remain valid. Simulations indicate that our method performs similar to fitting the model on a full cohort, both in terms of parameters estimates and predictions of survival probabilities. Estimating the model on the classical version of the case-cohort design shows clear bias and worse performance of the predictions. The procedure is further illustrated in data from a biomarker study on acute coronary syndrome patients, BIOMArCS.     

Dental students on instruction in local anaesthesia

In order to find out how dental students feel about their education in the application of local anaesthesia, a questionnaire was distributed via e-mail among all dental students in the Netherlands. A total of 397 completed questionnaires were analyzed statistically. At all 3 dental schools in the second year instruction in theoretical aspects of local anaesthesia began. Practical teaching began in the second or third study year. A preclinical training model was used by 15% of the students in Amsterdam, 20% of the students in Nijmegen and 35% of the students in Groningen. When they administered their first injection in a human, a fellow dental student in 91-98% of all cases, 24-74% of the students felt that they were insufficiently prepared. 35-52% of the students said that they would also like to receive instruction in intraligamentary anaesthesia in the dental curriculum. Other changes in the curriculum were also frequently suggested, especially the introduction of preclinical training models (29%, 55% and 56% for Groningen, Nijmegen and Amsterdam respectively).