183 research outputs found
Phase 3 Trial of 177Lu-Dotatate for Midgut Neuroendocrine Tumors
Background Patients with advanced midgut neuroendocrine tumors who have had disease progression during first-line somatostatin analogue therapy have limited therapeutic options. This randomized, controlled trial evaluated the efficacy and safety of lutetium-177 (177Lu)-Dotatate in patients with advanced, progressive, somatostatin-receptor-positive midgut neuroendocrine tumors. Methods We randomly assigned 229 patients who had well-differentiated, metastatic midgut neuroendocrine tumors to receive either 177Lu-Dotatate (116 patients) at a dose of 7.4 GBq every 8 weeks (four intravenous infusions, plus best supportive care including octreotide long-acting repeatable [LAR] administered intramuscularly at a dose of 30 mg) (177Lu-Dotatate group) or octreotide LAR alone (113 patients) administered intramuscularly at a dose of 60 mg every 4 weeks (control group). The primary end point was progression-free survival. Secondary end points included the objective response rate, overall survival, safety, and the side-effect profile. The final analysis of overall survival will be conducted in the future as specified in the protocol; a prespecified interim analysis of overall survival was conducted and is reported here. Results At the data-cutoff date for the primary analysis, the estimated rate of progression-free survival at month 20 was 65.2% (95% confidence interval [CI], 50.0 to 76.8) in the 177Lu-Dotatate group and 10.8% (95% CI, 3.5 to 23.0) in the control group. The response rate was 18% in the 177Lu-Dotatate group versus 3% in the control group (P<0.001). In the planned interim analysis of overall survival, 14 deaths occurred in the 177Lu-Dotatate group and 26 in the control group (P=0.004). Grade 3 or 4 neutropenia, thrombocytopenia, and lymphopenia occurred in 1%, 2%, and 9%, respectively, of patients in the 177Lu-Dotatate group as compared with no patients in the control group, with no evidence of renal toxic effects during the observed time frame. Conclusions Treatment with 177Lu-Dotatate resulted in markedly longer progression-free survival and a significantly higher response rate than high-dose octreotide LAR among patients with advanced midgut neuroendocrine tumors. Preliminary evidence of an overall survival benefit was seen in an interim analysis; confirmation will be required in the planned final analysis. Clinically significant myelosuppression occurred in less than 10% of patients in the 177Lu-Dotatate group. (Funded by Advanced Accelerator Applications; NETTER-1 ClinicalTrials.gov number, NCT01578239 ; EudraCT number 2011-005049-11
Proteomics: in pursuit of effective traumatic brain injury therapeutics
Effective traumatic brain injury (TBI) therapeutics remain stubbornly elusive. Efforts in the field have been challenged by the heterogeneity of clinical TBI, with greater complexity among underlying molecular phenotypes than initially conceived. Future research must confront the multitude of factors comprising this heterogeneity, representing a big data challenge befitting the coming informatics age. Proteomics is poised to serve a central role in prescriptive therapeutic development, as it offers an efficient endpoint within which to assess post-TBI biochemistry. We examine rationale for multifactor TBI proteomic studies and the particular importance of temporal profiling in defining biochemical sequences and guiding therapeutic development. Lastly, we offer perspective on repurposing biofluid proteomics to develop theragnostic assays with which to prescribe, monitor and assess pharmaceutics for improved translation and outcome for TBI patients
Reaction rates and transport in neutron stars
Understanding signals from neutron stars requires knowledge about the
transport inside the star. We review the transport properties and the
underlying reaction rates of dense hadronic and quark matter in the crust and
the core of neutron stars and point out open problems and future directions.Comment: 74 pages; commissioned for the book "Physics and Astrophysics of
Neutron Stars", NewCompStar COST Action MP1304; version 3: minor changes,
references updated, overview graphic added in the introduction, improvements
in Sec IV.A.
Mapping atopic dermatitis and anti–IL-22 response signatures to type 2–low severe neutrophilic asthma
Background: Transcriptomic changes in patients who respond clinically to biological therapies may identify responses in other tissues or diseases. Objective: We sought to determine whether a disease signature identified in atopic dermatitis (AD) is seen in adults with severe asthma and whether a transcriptomic signature for patients with AD who respond clinically to anti–IL-22 (fezakinumab [FZ]) is enriched in severe asthma. Methods: An AD disease signature was obtained from analysis of differentially expressed genes between AD lesional and nonlesional skin biopsies. Differentially expressed genes from lesional skin from therapeutic superresponders before and after 12 weeks of FZ treatment defined the FZ-response signature. Gene set variation analysis was used to produce enrichment scores of AD and FZ-response signatures in the Unbiased Biomarkers for the Prediction of Respiratory Disease Outcomes asthma cohort. Results: The AD disease signature (112 upregulated genes) encompassing inflammatory, T-cell, TH2, and TH17/TH22 pathways was enriched in the blood and sputum of patients with asthma with increasing severity. Patients with asthma with sputum neutrophilia and mixed granulocyte phenotypes were the most enriched (P < .05). The FZ-response signature (296 downregulated genes) was enriched in asthmatic blood (P < .05) and particularly in neutrophilic and mixed granulocytic sputum (P < .05). These data were confirmed in sputum of the Airway Disease Endotyping for Personalized Therapeutics cohort. IL-22 mRNA across tissues did not correlate with FZ-response enrichment scores, but this response signature correlated with TH22/IL-22 pathways. Conclusions: The FZ-response signature in AD identifies severe neutrophilic asthmatic patients as potential responders to FZ therapy. This approach will help identify patients for future asthma clinical trials of drugs used successfully in other chronic diseases
Expression of miRNA-106b in conventional renal cell carcinoma is a potential marker for prediction of early metastasis after nephrectomy
<p>Abstract</p> <p>Background</p> <p>MicroRNAs are endogenously expressed regulatory noncoding RNAs. Previous studies have shown altered expression levels of several microRNAs in renal cell carcinoma.</p> <p>Methods</p> <p>We examined the expression levels of selected microRNAs in 38 samples of conventional renal cell carcinoma (RCC) and 10 samples of non-tumoral renal parenchyma using TaqMan real-time PCR method.</p> <p>Results</p> <p>The expression levels of miRNA-155 (p < 0.0001), miRNA-210 (p < 0.0001), miRNA-106a (p < 0.0001) and miRNA-106b (p < 0.0001) were significantly over-expressed in tumor tissue, whereas the expression of miRNA-141 (p < 0.0001) and miRNA-200c (p < 0.0001) were significantly decreased in RCC samples. There were no significant differences between expression levels of miRNA-182 and miRNA-200b in tumor samples and renal parenchyma. Our data suggest that expression levels of miRNA-106b are significantly lower in tumors of patients who developed metastasis (p = 0.030) and miR-106b is a potential predictive marker of early metastasis after nephrectomy in RCC patients (long-rank p = 0.032).</p> <p>Conclusions</p> <p>We have confirmed previous observations obtained by miRNA microarray analysis using standardized real-time PCR method. For the first time, we have identified a prognostic significance of miRNA-106b, which, after validation on a larger group of patients, maybe useful as a promising biomarker in patients with RCC.</p
Fast MCMC sampling for hidden markov models to determine copy number variations
<p>Abstract</p> <p>Background</p> <p>Hidden Markov Models (HMM) are often used for analyzing Comparative Genomic Hybridization (CGH) data to identify chromosomal aberrations or copy number variations by segmenting observation sequences. For efficiency reasons the parameters of a HMM are often estimated with maximum likelihood and a segmentation is obtained with the Viterbi algorithm. This introduces considerable uncertainty in the segmentation, which can be avoided with Bayesian approaches integrating out parameters using Markov Chain Monte Carlo (MCMC) sampling. While the advantages of Bayesian approaches have been clearly demonstrated, the likelihood based approaches are still preferred in practice for their lower running times; datasets coming from high-density arrays and next generation sequencing amplify these problems.</p> <p>Results</p> <p>We propose an approximate sampling technique, inspired by compression of discrete sequences in HMM computations and by <it>kd</it>-trees to leverage spatial relations between data points in typical data sets, to speed up the MCMC sampling.</p> <p>Conclusions</p> <p>We test our approximate sampling method on simulated and biological ArrayCGH datasets and high-density SNP arrays, and demonstrate a speed-up of 10 to 60 respectively 90 while achieving competitive results with the state-of-the art Bayesian approaches.</p> <p><it>Availability: </it>An implementation of our method will be made available as part of the open source GHMM library from <url>http://ghmm.org</url>.</p
Mutations in PIK3CA are infrequent in neuroblastoma
BACKGROUND: Neuroblastoma is a frequently lethal pediatric cancer in which MYCN genomic amplification is highly correlated with aggressive disease. Deregulated MYC genes require co-operative lesions to foster tumourigenesis and both direct and indirect evidence support activated Ras signaling for this purpose in many cancers. Yet Ras genes and Braf, while often activated in cancer cells, are infrequent targets for activation in neuroblastoma. Recently, the Ras effector PIK3CA was shown to be activated in diverse human cancers. We therefore assessed PIK3CA for mutation in human neuroblastomas, as well as in neuroblastomas arising in transgenic mice with MYCN overexpressed in neural-crest tissues. In this murine model we additionally surveyed for Ras family and Braf mutations as these have not been previously reported. METHODS: Sixty-nine human neuroblastomas (42 primary tumors and 27 cell lines) were sequenced for PIK3CA activating mutations within the C2, helical and kinase domain "hot spots" where 80% of mutations cluster. Constitutional DNA was sequenced in cases with confirmed alterations to assess for germline or somatic acquisition. Additionally, Ras family members (Hras1, Kras2 and Nras) and the downstream effectors Pik3ca and Braf, were sequenced from twenty-five neuroblastomas arising in neuroblastoma-prone transgenic mice. RESULTS: We identified mutations in the PIK3CA gene in 2 of 69 human neuroblastomas (2.9%). Neither mutation (R524M and E982D) has been studied to date for effects on lipid kinase activity. Though both occurred in tumors with MYCN amplification the overall rate of PIK3CA mutations in MYCN amplified and single-copy tumors did not differ appreciably (2 of 31 versus 0 of 38, respectively). Further, no activating mutations were identified in a survey of Ras signal transduction genes (including Hras1, Kras2, Nras, Pik3ca, or Braf genes) in twenty-five neuroblastic tumors arising in the MYCN-initiated transgenic mouse model. CONCLUSION: These data suggest that activating mutations in the Ras/Raf-MAPK/PI3K signaling cascades occur infrequently in neuroblastoma. Further, despite compelling evidence for MYC and RAS cooperation in vitro and in vivo to promote tumourigenesis, activation of RAS signal transduction does not constitute a preferred secondary pathway in neuroblastomas with MYCN deregulation in either human tumors or murine models
Experimental evidence for splicing of intron-containing transcripts of plant LTR retrotransposon Ogre
Ogre elements are a distinct group of plant Ty3/gypsy-like retrotransposons characterized by several specific features, one of which is a separation of the gag-pol region into two non-overlapping open reading frames: ORF2 coding for Gag-Pro, and ORF3 coding for RT/RH-INT proteins. Previous characterization of Ogre elements from several plant species revealed that part of their transcripts lacks the region between ORF2 and ORF3, carrying one uninterrupted ORF instead. In this work, we investigated a hypothesis that this region represents an intron that is spliced out from part of the Ogre transcripts as a means for preferential production of ORF2-encoded proteins over those encoded by the complete ORF2–ORF3 region. The experiments involved analysis of transcription patterns of well-defined Ogre populations in a model plant Medicago truncatula and examination of transcripts carrying dissected pea Ogre intron expressed within a coding sequence of chimeric reporter gene. Both experimental approaches proved that the region between ORF2 and ORF3 is spliced from Ogre transcripts and showed that this process is only partial, probably due to weak splice signals. This is one of very few known cases of spliced LTR retrotransposons and the only one where splicing does not involve parts of the element’s coding sequences, thus resembling intron splicing found in most cellular genes
Plasma ACE2 predicts outcome of COVID-19 in hospitalized patients
AimsSevere acute respiratory syndrome coronavirus 2 (SARS-CoV-2) binds to angiotensin converting enzyme 2 (ACE2) enabling entrance of the virus into cells and causing the infection termed coronavirus disease of 2019 (COVID-19). Here, we investigate associations between plasma ACE2 and outcome of COVID-19.Methods and resultsThis analysis used data from a large longitudinal study of 306 COVID-19 positive patients and 78 COVID-19 negative patients (MGH Emergency Department COVID-19 Cohort). Comprehensive clinical data were collected on this cohort, including 28-day outcomes. The samples were run on the Olink® Explore 1536 platform which includes measurement of the ACE2 protein. High admission plasma ACE2 in COVID-19 patients was associated with increased maximal illness severity within 28 days with OR = 1.8, 95%-CI: 1.4-2.3 (P ConclusionThis study suggests that measuring plasma ACE2 is potentially valuable in predicting COVID-19 outcomes. Further, ACE2 could be a link between COVID-19 illness severity and its established risk factors hypertension, pre-existing heart disease and pre-existing kidney disease
Body indices and basic vital signs in Helicobacter pylori positive and negative persons
It has been hypothesized that Helicobacter pylori (Hp) infection may contribute to reduced stature, risk of hypertension or obesity. The aim was to evaluate body indices in Hp positive and negative persons. A total of 2436 subjects (4–100 years old) were tested for Hp status by 13Curea breath test. Data on height and weight were collected for 84%, and blood pressure for 80% of the study subjects. The prevalence of Hp infection was 41.6%. The odds ratio for a 10-year increase in age was 1.21 (95% CI 1.17–1.25, p-value <0.001). Statistically significant negative association of Hp positivity with body height was most pronounced in the younger age groups, while a positive association of Hp positivity with body mass index was only seen in those aged 15+ years. There was a negative effect of Hp positivity on systolic and diastolic blood pressure in subjects below 25 and a relatively strong positive effect on blood pressure in subjects over 65 years. Residual confounding by social characteristics as a possible explanation for the associations of Hp positivity with height and blood pressure cannot be excluded. Unmeasured factors related to social and family environment may cause the apparent association between Hp positivity and children’s growth and blood pressure
- …