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101.
Glioblastoma (GBM) is a deadly disease with a need for deeper understanding and new therapeutic approaches. The microenvironment of glioblastoma has previously been shown to guide glioblastoma progression. In this study, astrocytes were investigated with regard to their effect on glioblastoma proliferation through correlative analyses of clinical samples and experimental in vitro and in vivo studies. Co-culture techniques were used to investigate the GBM growth enhancing potential of astrocytes. Cell sorting and RNA sequencing were used to generate a GBM-associated astrocyte signature and to investigate astrocyte-induced GBM genes. A NOD scid GBM mouse model was used for in vivo studies. A gene signature reflecting GBM-activated astrocytes was associated with poor prognosis in the TCGA GBM dataset. Two genes, periostin and serglycin, induced in GBM cells upon exposure to astrocytes were expressed at higher levels in cases with high “astrocyte signature score”. Astrocytes were shown to enhance glioblastoma cell growth in cell lines and in a patient-derived culture, in a manner dependent on cell–cell contact and involving increased cell proliferation. Furthermore, co-injection of astrocytes with glioblastoma cells reduced survival in an orthotopic GBM model in NOD scid mice. In conclusion, this study suggests that astrocytes contribute to glioblastoma growth and implies this crosstalk as a candidate target for novel therapies.  相似文献   
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Structural bone allografts often fracture due to their lack of osteogenic and remodeling potential. To overcome these limitations, we utilized allografts coated with recombinant adeno-associated virus (rAAV) that mediate in vivo gene transfer. Using beta-galactosidase as a reporter gene, we show that 4-mm murine femoral allografts coated with rAAV-LacZ are capable of transducing adjacent inflammatory cells and osteoblasts in the fracture callus following transplantation. While this LacZ vector had no effect on allograft healing, bone morphogenetic protein signals delivered via rAAV-caAlk2 coating induced endochondral bone formation directly on the cortical surface of the allograft by day 14. By day 28 there was evidence of remodeling of the new woven bone and massive osteoclastic resorption of the cortical surface of the rAAV-caAlk2-coated allografts only. Micro-CT analysis of rAAV-LacZ- vs rAAV-caAlk2-coated allografts after 42 days of healing demonstrated a significant increase in new bone formation (0.67 +/- 0.21 vs 2.49 +/- 0.40 mm(3); P < 0.005). Furthermore, the 3D micro-CT images of femurs grafted with rAAV-Alk2-coated allografts provided the first evidence that complete bridging of bone around a cortical allograft is possible. These results indicate that cell-free, rAAV-coated allografts have the potential to revitalize in vivo following transplantation.  相似文献   
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In this article, we explore medical doctors’ moral experiences of being responsible for decisions on the lives and sometimes deaths of infants in a Danish Neonatal Intensive Care Unit (NICU). Drawing on fieldwork, we investigate how clinicians navigate the tension between exercising medical authority and enabling parental involvement in decisions. Introducing the term “careography”, we call attention to how the doctors steer this tension through care for the infant, parents, colleagues, and society in ways that help them overcome moral ambivalences. We suggest that “careography” holds analytical potential to bridge anthropological theories of power, experience, and care.  相似文献   
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Background

Hypospadias is a relatively common congenital malformation. Data on temporal trends in prevalence of hypospadias are conflicting. It is unclear whether changes of maternal age distribution over time are associated with changes in hypospadias prevalence.

Objective

To study changes in prevalence of hypospadias in Denmark during a 29-yr period and to investigate whether maternal age was associated with the prevalence of hypospadias.

Design, setting, and participants

Through Denmark's National Patient Registry, covering all Danish hospitals, we identified all boys diagnosed with hypospadias in Denmark. From the Danish Medical Birth Registry, we obtained information on maternal age and on the annual total number of live-born boys from 1977 to 2005.

Measurements

Prevalence of hypospadias at birth.

Results and limitations

Among 921 745 boys born alive from 1977 to 2005, we identified 3490 boys with hypospadias. The prevalence increased from 0.24% in 1977 to 0.52% in 2005, corresponding with an annual increase in prevalence of 2.40% (95% confidence interval: 1.94–2.86). The prevalence of hypospadias did not differ according to maternal age. The mean annual prevalence was 0.38% in sons of mothers aged ≤25 yr, 0.37% in sons of mothers aged 26–30 yr, 0.39% in sons of mothers aged 31–35 yr, and 0.39% in sons of mothers >35 yr.

Conclusions

The hypospadias prevalence was increasing in Denmark from 1977 to 2005. Increased maternal age did not explain this trend.  相似文献   
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Background: Patients with inflammatory bowel disease (IBD) and symptoms of irritable bowel syndrome (IBS) may be intolerant to fermentable carbohydrates (FODMAPs). The aim of this study was to test the feasibility of eliminating and subsequently reintroducing FODMAPs in patients with IBS symptoms as part of the IBD manifestation and to compare the severity of IBS symptoms and pain, bloating and quality of life (QoL). Methods: An eight-week randomised open-label FODMAP elimination with double-blinded, crossover provocations of FODMAP and placebo. Diet patients were on a low-FODMAP diet for eight weeks with blinded two-week provocations after two and six weeks. Questionnaires, blood and stool samples were collected. Results: Patient enrolment was challenging. Nineteen participants were included in the study. Eliminating low FODMAP for two weeks resulted in significant decreases in pain and bloating scores (p < 0.003), whereas there were no statistical differences in pain scores between diet patients and controls. Pain and bloating scores increased, returning to baseline levels after two weeks of double-blinded provocations with placebo, (p > 0.05). Conclusions: The results document the possibility of performing a randomised controlled study following the gold standard for testing food intolerance with blinding of the Low FODMAP diet. Recruitment of participants was challenging.  相似文献   
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