228 resultados para Honkavaara, Katja
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Background Locking compression plates are used in various configurations with lack of detailed information on consequent bone healing. Study design In this in vivo study in sheep 5 different applications of locking compression plate (LCP) were tested using a 45° oblique osteotomy simulating simple fracture pattern. 60 Swiss Alpine sheep where assigned to 5 different groups with 12 sheep each (Group 1: interfragmentary lag screw and an LCP fixed with standard cortex screws as neutralisation plate; Group 2: interfragmentary lag screw and LCP with locking head screws; Group 3: compression plate technique (hybrid construct); Group 4: internal fixator without fracture gap; Group 5: internal fixator with 3 mm gap at the osteotomy site). One half of each group (6 sheep) was monitored for 6 weeks, and the other half (6 sheep) where followed for 12 weeks. Methods X-rays at 3, 6, 9 and 12 weeks were performed to monitor the healing process. After sacrifice operated tibiae were tested biomechanically for nondestructive torsion and compared to the tibia of the healthy opposite side. After testing specimens were processed for microradiography, histology, histomorphometry and assessment of calcium deposition by fluorescence microscopy. Results In all groups bone healing occurred without complications. Stiffness in biomechanical testing showed a tendency for higher values in G2 but results were not statistically significant. Values for G5 were significantly lower after 6 weeks, but after 12 weeks values had improved to comparable results. For all groups, except G3, stiffness values improved between 6 and 12 weeks. Histomorphometrical data demonstrate endosteal callus to be more marked in G2 at 6 weeks. Discussion and conclusion All five configurations resulted in undisturbed bone healing and are considered safe for clinical application.
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BACKGROUND Perioperative chemotherapy improves survival in patients with advanced esophagogastric cancer, but the optimal treatment regimen remains unclear. More intensive chemotherapy may improve outcome, but also increase toxicity and complications. METHODS A total of 843 patients were included in this retrospective study and stratified in 4 groups: doublet therapy with cisplatin or oxaliplatin and 5-fluorouracil (groups A/B) or triplet therapy with additional epirubicin or taxane (groups C/D). The influence of the different neoadjuvant chemotherapy regimens on response, prognosis, and complications was assessed. RESULTS Clinical and pathological response were associated with longer overall survival (OS; p < 0.001). No significant differences regarding response or OS were found, but there was a trend toward better outcome in group D (taxane-containing triplet). In the subgroup of 669 patients with adenocarcinomas of the esophagogastric junction (AEG), patients who had received taxane-containing regimens had a significantly longer OS (p = 0.037), but taxane use was not an independent factor in multivariate analysis. Triple therapy with taxanes did not result in a higher complication rate or postoperative mortality. CONCLUSIONS Although no superior neoadjuvant chemotherapy regimen was identified for patients with esophagogastric adenocarcinoma, taxane-containing regimens should be further investigated in randomized trials, especially in patients with AEG tumors.
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BACKGROUND NOTCH signaling can exert oncogenic or tumor suppressive functions and can contribute to chemotherapy resistance in cancer. In this study, we aimed to clarify the clinicopathological significance and the prognostic and predictive value of NOTCH1 and NOTCH2 expression in gastric cancer (GC). METHODS NOTCH1 and NOTCH2 expression was determined immunohistochemically in 142 primarily resected GCs using tissue microarrays and in 84 pretherapeutic biopsies from patients treated by neoadjuvant chemotherapy. The results were correlated with survival, response to therapy, and clinico-pathological features. RESULTS Primarily resected patients with NOTCH1-negative tumors demonstrated worse survival. High NOTCH1 expression was associated with early-stage tumors and with significantly increased survival in this subgroup. Higher NOTCH2 expression was associated with early-stage and intestinal-type tumors and with better survival in the subgroup of intestinal-type tumors. In pretherapeutic biopsies, higher NOTCH1 and NOTCH2 expression was more frequent in non-responding patients, but these differences were statistically not significant. CONCLUSION Our findings suggested that, in particular, NOTCH1 expression indicated good prognosis in GC. The close relationship of high NOTCH1 and NOTCH2 expression with early tumor stages may indicate a tumor-suppressive role of NOTCH signaling in GC. The role of NOTCH1 and NOTCH2 in neoadjuvantly treated GC is limited.
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Whole exome sequencing (WES) is increasingly used in research and diagnostics. WES users expect coverage of the entire coding region of known genes as well as sufficient read depth for the covered regions. It is, however, unknown which recent WES platform is most suitable to meet these expectations. We present insights into the performance of the most recent standard exome enrichment platforms from Agilent, NimbleGen and Illumina applied to six different DNA samples by two sequencing vendors per platform. Our results suggest that both Agilent and NimbleGen overall perform better than Illumina and that the high enrichment performance of Agilent is stable among samples and between vendors, whereas NimbleGen is only able to achieve vendor- and sample-specific best exome coverage. Moreover, the recent Agilent platform overall captures more coding exons with sufficient read depth than NimbleGen and Illumina. Due to considerable gaps in effective exome coverage, however, the three platforms cannot capture all known coding exons alone or in combination, requiring improvement. Our data emphasize the importance of evaluation of updated platform versions and suggest that enrichment-free whole genome sequencing can overcome the limitations of WES in sufficiently covering coding exons, especially GC-rich regions, and in characterizing structural variants.
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Elevated concentrations of albumin in the urine, albuminuria, are a hallmark of diabetic kidney disease and associate with increased risk for end-stage renal disease and cardiovascular events. To gain insight into the pathophysiological mechanisms underlying albuminuria, we conducted meta-analyses of genome-wide association studies and independent replication in up to 5,825 individuals of European ancestry with diabetes mellitus and up to 46,061 without diabetes, followed by functional studies. Known associations of variants in CUBN, encoding cubilin, with the urinary albumin-to-creatinine ratio (UACR) were confirmed in the overall sample (p=2.4*10(-10)). Gene-by-diabetes interactions were detected and confirmed for variants in HS6ST1 and near RAB38/CTSC. SNPs at these loci demonstrated a genetic effect on UACR in individuals with but not without diabetes. The change in average UACR per minor allele was 21% for HS6ST1 and 13% for RAB38/CTSC (p=6.3*10(-7) and 5.8*10(-7), respectively). Experiments using streptozotocin-treated diabetic Rab38 knockout and control rats showed higher urinary albumin concentrations and reduced amounts of megalin and cubilin at the proximal tubule cell surface in Rab38 knockout vs. control rats. Relative expression of RAB38 was higher in tubuli of patients with diabetic kidney disease compared to controls. The loci identified here confirm known and highlight novel pathways influencing albuminuria.
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Le présent article examine dans quelle mesure l’organisation des trajectoires scolaires et les parcours conduisant à l’enseignement supérieur favorisent la mobilité sociale ou au contraire la reproduction des inégalités. Nous avons comparé trois pays : la France, la Suisse et le Canada. Les résultats obtenus à partir des données tirées des panels d’enquêtes menées dans ces trois pays permettent d’observer deux situations opposées. Plus l’enseignement supérieur est valorisé au détriment de la formation professionnelle, plus les inégalités d’accès à l’enseignement supérieur ont tendance à s’exacerber. La compétition y est telle que ce sont les jeunes de milieu favorisé qui tirent davantage profit de son expansion. Par contre, lorsque la formation professionnelle est valorisée, les inégalités auraient plutôt tendance à être modérées.
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Familial acute myeloid leukemia is rare and linked to germline mutations in RUNX1, GATA2 or CCAAT/enhancer binding protein-α (CEBPA). We re-evaluated a large family with acute myeloid leukemia originally seen at NIH in 1969. We utilized whole-exome sequencing to study this family, and conducted in silico bioinformatics analysis, protein structural modeling and laboratory experiments to assess the impact of the identified CEBPA Q311P mutation. Unlike most previously identified germline mutations in CEBPA, which were N-terminal frameshift mutations, we identified a novel Q311P variant that was located in the C-terminal bZip domain of C/EBPα. Protein structural modeling suggested that the Q311P mutation alters the ability of the CEBPA dimer to bind DNA. Electrophoretic mobility shift assays showed that the Q311P mutant had attenuated binding to DNA, as predicted by the protein modeling. Consistent with these findings, we found that the Q311P mutation has reduced transactivation, consistent with a loss-of-function mutation. From 45 years of follow-up, we observed incomplete penetrance (46%) of CEBPA Q311P. This study of a large multi-generational pedigree reveals that a germline mutation in the C-terminal bZip domain can alter the ability of C/EBP-α to bind DNA and reduces transactivation, leading to acute myeloid leukemia.
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PURPOSE In acute myeloid leukemia (AML), the transcription factors CEBPA and KLF4 as well as the universal tumor suppressor p53 are frequently deregulated. Here, we investigated the extent of dysregulation, the molecular interactions, and the mechanisms involved. EXPERIMENTAL DESIGN One hundred ten AML patient samples were analyzed for protein levels of CEBPA, KLF4, p53, and p53 modulators. Regulation of CEBPA gene expression by KLF4 and p53 or by chemical p53 activators was characterized in AML cell lines. RESULTS We found that CEBPA gene transcription can be directly activated by p53 and KLF4, suggesting a p53-KLF4-CEBPA axis. In AML patient cells, we observed a prominent loss of p53 function and concomitant reduction of KLF4 and CEBPA protein levels. Assessment of cellular p53 modulator proteins indicated that p53 inactivation in leukemic cells correlated with elevated levels of the nuclear export protein XPO1/CRM1 and increase of the p53 inhibitors MDM2 and CUL9/PARC in the cytoplasm. Finally, restoring p53 function following treatment with cytotoxic chemotherapy compounds and p53 restoring non-genotoxic agents induced CEBPA gene expression, myeloid differentiation, and cell-cycle arrest in AML cells. CONCLUSIONS The p53-KLF4-CEBPA axis is deregulated in AML but can be functionally restored by conventional chemotherapy and novel p53 activating treatments. Clin Cancer Res; 22(3); 746-56. ©2015 AACR.
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Vinorelbine chemotherapy with granulocyte-colony stimulating factor (G-CSF) stimulation is a widely applied non-myelosuppressive mobilization regimen in Switzerland for myeloma patients, but its neurotoxic potential limits its use in patients with bortezomib-induced polyneuropathy. In this single-center study, we alternatively evaluated safety and effectiveness of gemcitabine chemotherapy with G-CSF for mobilization of autologous stem cells. Between March 2012 and February 2013, all bortezomib-pretreated myeloma patients planned to undergo first-line high-dose melphalan chemotherapy received a single dose of 1250 mg/m(2) gemcitabine, with G-CSF started on day 4. The 24 patients in this study had received a median of four cycles of bortezomib-dexamethason-based induction. Bortezomib-related polyneuropathy was identified in 21 patients (88%) by clinical evaluation and a standardized questionnaire. Administration of gemcitabine mobilization did not induce new or aggravate pre-existing neuropathy. Stem cell mobilization was successful in all 24 patients, with a single day of apheresis being sufficient in 19 patients (78%). The median yield was 9.51 × 10(6) CD34+ cells/kg. Stem collection could be accomplished at day 8 in 67%. Our data suggest that single-dose gemcitabine together with G-CSF is an effective mobilization regimen in myeloma patients and a safe alternative non-myelosuppressive mobilization chemotherapy for myeloma patients with bortezomib-induced polyneuropathy.
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Calreticulin (CALR) is a highly conserved, multifunctional protein involved in a variety of cellular processes including the maintenance of intracellular calcium homeostasis, proper protein folding, differentiation and immunogenic cell death. More recently, a crucial role for CALR in the pathogenesis of certain hematologic malignancies was discovered: in clinical subgroups of acute myeloid leukemia, CALR overexpression mediates a block in differentiation, while somatic mutations have been found in the majority of patients with myeloproliferative neoplasms with nonmutated Janus kinase 2 gene (JAK2) or thrombopoietin receptor gene (MPL). However, the mechanisms underlying CALR promoter activation have insufficiently been investigated so far. By dissecting the core promoter region, we could identify a functional TATA-box relevant for transcriptional activation. In addition, we characterized two evolutionary highly conserved cis-regulatory modules (CRMs) within the proximal promoter each composed of one binding site for the transcription factors SP1 and SP3 as well as for the nuclear transcription factor Y (NFY) and we verified binding of these factors to their cognate sites in vitro and in vivo.
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Vinorelbine chemotherapy with G-CSF stimulation is the standard mobilization regimen in Switzerland for multiple myeloma patients. However, with the increasing use of bortezomib during induction treatment, adding the neurotoxic compound vinorelbine for mobilization may aggravate bortezomib-induced polyneuropathy. In this retrospective single-center study, we aimed to explore vinorelbine mediated neuropathy in 106 consecutive bortezomib pretreated myeloma patients. We confirmed that vinorelbine with G-CSF represents a reliable and effective regimen for mobilization of autologous stem cells. However, the single administration of 35 mg/m(2) vinorelbine added significant neurotoxicity. We found that 24 patients (24%) reported vinorelbine mediated neurotoxicity: Aggravation of bortezomib-induced neuropathy was observed in 17 patients (17%), and vinorelbine mobilization induced first occurrence of polyneuropathy in additional 7 patients (7%). We observed that development of polyneuropathy was not associated with differing survival rates. Finally, affected patients reported polyneuropathy associated disease burden as "very high" in 13% and "high" in 50%. Our data indicate that a single administration of vinorelbine to mobilize autologous stem cells is associated with significant additional polyneuropathy in bortezomib pretreated myeloma patients. The efficacy of vinorelbine mobilization should be balanced against its neurotoxic potential.
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Novel strategies aiming to increase survival rates in patients with advanced-stage mantle cell lymphoma (MCL) and relapsing diffuse large B-cell lymphoma (DLBCL) are a clinical need. High-dose chemotherapy (HDCT) with autologous stem cell transplantation (ASCT) has improved progression-free (PFS) and overall survival (OS) in MCL and relapsed DLBCL. However, the role of CD34+ cell selection before ASCT in MCL and DLBCL is unclear. We retrospectively analyzed the outcome of 62 consecutive patients with advanced-stage MCL or relapsed DLBCL undergoing ASCT with (n=31) or without (n=31) prior CD34+ selection. All patients had stage III or IV disease, with 47% having DLBCL and 53% MCL. The median duration for neutrophil and platelet recovery was 12 and 16 days in CD34+ selected patients, and 11 (P<.001) and 14 days (P=.012) in the group without selection, respectively. No differences in toxicities were observed. The 5-year PFS for CD34+ selected versus not selected patients was 67% and 39% (P=.016), and the 5-year OS was 86% and 54% (P=.007). Our data suggest that using CD34+ selected autografts for ASCT in advanced stage MCL and DLBCL is associated with longer PFS and OS without increased toxicity.
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BACKGROUND AND PURPOSE We evaluated cerebral white and gray matter changes in patients with iRLS in order to shed light on the pathophysiology of this disease. METHODS Twelve patients with iRLS were compared to 12 age- and sex-matched controls using whole-head diffusion tensor imaging (DTI) and voxel-based morphometry (VBM) techniques. Evaluation of the DTI scans included the voxelwise analysis of the fractional anisotropy (FA), radial diffusivity (RD), and axial diffusivity (AD). RESULTS Diffusion tensor imaging revealed areas of altered FA in subcortical white matter bilaterally, mainly in temporal regions as well as in the right internal capsule, the pons, and the right cerebellum. These changes overlapped with changes in RD. Voxel-based morphometry did not reveal any gray matter alterations. CONCLUSIONS We showed altered diffusion properties in several white matter regions in patients with iRLS. White matter changes could mainly be attributed to changes in RD, a parameter thought to reflect altered myelination. Areas with altered white matter microstructure included areas in the internal capsule which include the corticospinal tract to the lower limbs, thereby supporting studies that suggest changes in sensorimotor pathways associated with RLS.