The zebrafish mutants dre, uki, and lep encode negative regulators of the hedgehog signaling pathway.

Proliferation is one of the basic processes that control embryogenesis. To identify factors involved in the regulation of proliferation, we performed a zebrafish genetic screen in which we used proliferating cell nuclear antigen (PCNA) expression as a readout. Two mutants, hu418B and hu540A, show increased PCNA expression. Morphologically both mutants resembled the dre (dreumes), uki (ukkie), and lep (leprechaun) mutant class and both are shown to be additional uki alleles. Surprisingly, although an increased size is detected of multiple structures in these mutant embryos, adults become dwarfs. We show that these mutations disrupt repressors of the Hedgehog (Hh) signaling pathway. The dre, uki, and lep loci encode Su(fu) (suppressor of fused), Hip (Hedgehog interacting protein), and Ptc2 (Patched2) proteins, respectively. This class of mutants is therefore unique compared to previously described Hh mutants from zebrafish genetic screens, which mainly show loss of Hh signaling. Furthermore, su(fu) and ptc2 mutants have not been described in vertebrate model systems before. Inhibiting Hh activity by cyclopamine rescues uki and lep mutants and confirms the overactivation of the Hh signaling pathway in these mutants. Triple uki/dre/lep mutants show neither an additive increase in PCNA expression nor enhanced embryonic phenotypes, suggesting that other negative regulators, possibly Ptc1, prevent further activation of the Hh signaling pathway. The effects of increased Hh signaling resulting from the genetic alterations in the uki, dre, and lep mutants differ from phenotypes described as a result of Hh overexpression and therefore provide additional insight into the role of Hh signaling during vertebrate development

A microcosting study of the surgical correction of upper extremity deformity in children with spastic cerebral palsy

_Objective:_ Determine healthcare costs of upper-extremity surgical correction in children with spastic cerebral palsy (CP). _Method:_ This cohort study included 39 children with spastic CP who had surgery for their upper extremity at a Dutch hospital. A retrospective cost analysis was performed including both hospital and rehabilitation costs. Hospital costs were determined using microcosting methodology. Rehabilitation costs were estimated using reference prices. _Results:_ Hospital costs averaged €6813 per child. Labor (50%), overheads (29%), and medical aids (15%) were important cost drivers. Rehabilitation costs were estimated at €3599 per child. _Conclusions:_ Surgery of the upper extremity is an important contributor to the healthcare costs of children with CP. Our study shows that labor is the most important cost driver for hospital costs, owing to the multidisciplinary approach and patient-specific treatment plan. A remarkable finding was the substantial amount of rehabilitation costs

Real-world cost-effectiveness of cetuximab in the third-line treatment of metastatic colorectal cancer based on patient chart review in the Netherlands

Objective: To assess the cost effectiveness of cetuximab in third-line treatment of patients with KRAS wild-type (wt) metastatic colorectal cancer (mCRC) in routine clinical practice compared with best supportive care (BSC). Methods: Patients (n = 287) with KRAS wt mCRC treated with cetuximab or BSC in eight hospitals in the Netherlands between 2009 and 2012 were included in our real-world study. Outcome measures were costs per life-year (LY) and costs per quality-adjusted LY (QALY) gained. A Markov model was developed, and a time horizon of four years was applied. Outcomes were calculated from Kaplan-Meier survival curves from patient-level data and literature. Direct medical costs were estimated in all centers (2013 values), and incremental cost-effectiveness ratios (ICERs) were calculated. Results were discounted, and a probabilistic sensitivity analysis was performed. Results: Administration of cetuximab in third-line treatment of mCRC resulted in a gain of 0.29 LYs and 0.25 QALYs compared with BSC. In the four-year study period, average discounted healthcare costs were €36,637 in the cetuximab group vs. €3648 in the BSC group. The discounted ICERs of cetuximab vs. BSC in the real-world setting were €114,907and €133,527 per LY and QALY gained, respectively. Conclusions: Results of this cost-effectiveness analysis showed that third-line treatment with cetuximab for patients with KRAS (exon 2) wt mCRC offered clinical benefits at additional cost. The real-world ICERs were in line with those of previously published cetuximab and panitumumab cost-utility models

Inadequate anti-polysaccharide antibody responses in the chicken

Chickens are notorious for the fact that they carry bacteria such as Salmonellae and Campylobacter, which can cause zoonoses by contamination of the end product, without hampering growth and development of the chicken itself. This carrier status can only been explained by the inability of the chickens immune system to eliminate the pathogen, this in turn being due to insufficient humoral responses towards the polysaccharides of the bacterial capsule. In a previous study, we demonstrated that in chickens a model thymus-independent type 2 (TI-2) polysaccharide antigen, trinitrophenylated Ficoll (TNP-Ficoll), hardly evokes a humoral immune response. Furthermore this TI-2 antigen was shown to exhibit a very specific initial localization pattern after intravenous injection, i.e. in the periellipsoidal lymphocyte sheaths (PELS) and the surrounding ring of macrophages. The functional equivalent of these macrophages in mammals, the marginal zone macrophages, were shown to suppress the humoral responses against TI-2 antigens. Therefore we investigated whether other standard TI-2 antigen models also induce low antibody responses, whether this low response is dose-dependent, and whether macrophages are responsible for this low response. It was found that other TI-2 antigens, such as hydroxyethyl starch and detoxified lipopolysaccharides, also induced very low IgM and IgG responses, indicating a general phenomenon that could not be overcome by using a higher dose of antigen. In addition, selective depletion of splenic macrophages with liposomes containing dichloromethylene diphosphonate prior to immunization increased the specific humoral response to TD and TI-1 antigens, but failed to do so for TI-2 antigen. This result indicates that the low humoral responses are not (only) due to a macrophage suppressive activity but also to other yet unknown mechanisms, for example the lack of responsive B cells in the splenic PELS

RAM 209

Sinds jaar en dag staat het prehistorische grafveld op de Boshoverheide bij Weert bekend als het grootste urnenveld van Nederland en een van de meest uitgestrekte van Noordwest-Europa. Met ruim 150 gerestaureerde grafheuvels is het bovendien een zeer zichtbaar archeologisch monument dat sinds 1968 wettelijk is beschermd. Toch speelde het grafveld tot nu toe slechts een marginale rol in het wetenschappelijke debat over het laat-prehistorisch grafritueel. Dat komt omdat de resultaten van onderzoeken uit de afgelopen jaren maar ten dele beschikbaar waren. In december 2008 kwamen kringgreppels in het wettelijk beschermde terrein bloot te liggen: het onbedoelde gevolg van natuurontwikkeling voor het reactiveren van stuifzand. Deze overwegingen leidden tot een aanvraag voor subsidie, en met de honorering ging een langgekoesterde wens in vervulling

Generation of a Dual-Functioning Antitumor Immune Response in the Peritoneal Cavity

Tumor cell metastasis to the peritoneal cavity is observed in patients with tumors of peritoneal organs, particularly colon and ovarian tumors. Following release into the peritoneal cavity, tumor cells rapidly attach to the omentum, a tissue consisting of immune aggregates embedded in adipose tissue. Despite their proximity to potential immune effector cells, tumor cells grow aggressively on these immune aggregates. We hypothesized that activation of the immune aggregates would generate a productive antitumor immune response in the peritoneal cavity. We immunized mice i.p. with lethally irradiated cells of the colon adenocarcinoma line Colon38. Immunization resulted in temporary enlargement of immune aggregates, and after challenge with viable Colon38 cells, we did not detect tumor growth on the omentum. When Colon38-immunized mice were challenged with cells from the unrelated breast adenocarcinoma line E0771 or the melanoma line B16, these tumors also did not grow. The nonspecific response was long-lived and not present systemically, highlighting the uniqueness of the peritoneal cavity. Cellular depletions of immune subsets revealed that NK1.1+ cells were essential in preventing growth of unrelated tumors, whereas NK1.1+ cells and T cells were essential in preventing Colon38 tumor growth. Collectively, these data demonstrate that the peritoneal cavity has a unique environment capable of eliciting potent specific and nonspecific antitumor immune responses

Cold case in het stuifzand : het urnenveld van de Boshoverheide bij Weert ontsloten

Met lit. opg