45 research outputs found
Immunochemical and Biochemical Analysis of the Guanine Nucleotide-Binding Protein, Goalpha, in the Neuroblastoma x Glioma Hybrid Cell, NG108-15
The aim of the work presented in this thesis was to investigate the status of the guanine nucleotide-binding protein, Go, in the neuroblastoma x glioma hybrid cell line, NG108-15 and to assess any functional changes brought about by morphological differentiation of these cells
Role of Hepatic Stellate Cells in the Early Phase of Liver Regeneration in Rat: Formation of Tight Adhesion to Parenchymal Cells
We investigated activation mechanisms of hepatic stellate cells (HSCs) that are known to play pivotal roles in the regeneration process after 70% partial hepatectomy (PHx). Parenchymal liver cells (PLCs) and non-parenchymal cells (NPLCs) were isolated and purified from the regenerating livers at 1, 3, 7, 14 days after PHx. Each liver cell fraction was stained by immunocytochemistry using an anti-desmin antibody as a marker for HSCs, anti-alpha-smooth muscle actin (alpha-SMA) as a marker for activated HSCs, and 5-bromo-2'-deoxyuridine (BrdU) for detection of proliferating cells. Tissue sections from regenerating livers were also analyzed by immunohistochemistry and compared with the results obtained for isolated cell fractions. One and 3 days after PHx, PLC-enriched fraction contained HSCs adhered to PLCs. The HSCs adhered to PLCs were double positive for BrdU and alpha-SMA, and formed clusters suggesting that these HSCs were activated. However, HSC-enriched fraction contained HSCs not adhered PLCs showed positive staining for anti-desmin antibody but negative for anti-alpha-SMA antibody. These results suggest that HSCs are activated by adhering to PLCs during the early phase of hepatic regeneration
Concurrent Supermassive Black Hole and Galazy Growth: Linking Environment and Nuclear Activity in Zeta Equals 2.23 H Alpha Emitters
We present results from an approximately equal 100 ks Chandra observation of the 2QZ Cluster 1004+00 structure at z = 2.23 (hereafter 2QZ Clus). 2QZ Clus was originally identified as an overdensity of four optically-selected QSOs at z = 2.23 within a 15 15 arcmin square region. Narrow-band imaging in the near-IR (within the K band) revealed that the structure contains an additional overdensity of 22 z = 2.23 H alpha-emitting galaxies (HAEs), resulting in 23 unique z = 2.23 HAEs/QSOs (22 within the Chandra field of view). Our Chandra observations reveal that three HAEs in addition to the four QSOs harbor powerfully accreting supermassive black holes (SMBHs), with 2-10 keV luminosities of approximately equal (8-60) 10(exp 43) erg s(exp1) and X-ray spectral slopes consistent with unobscured active galactic nucleus (AGN). Using a large comparison sample of 210 z = 2.23 HAEs in the Chandra-COSMOS field (C-COSMOS), we find suggestive evidence that the AGN fraction increases with local HAE galaxy density. The 2QZ Clus HAEs reside in a moderately overdense environment (a factor of approximately equal 2 times over the field), and after excluding optically-selected QSOs, we find that the AGN fraction is a factor of approximately equal 3.5(+3.8/ 2.2) times higher than C-COSMOS HAEs in similar environments. Using stacking analyses of the Chandra data and Herschel SPIRE observations at 250micrometers, we respectively estimate mean SMBH accretion rates ( M(BH)) and star formation rates (SFRs) for the 2QZ Clus and C-COSMOS samples. We find that the mean 2QZ Clus HAE stacked X-ray luminosity is QSO-like (L(210 keV) approximately equal [6-10] 10(exp 43) erg s(exp 1)), and the implied M(BH)/SFR approximately equal (1.6-3.2) 10(exp 3) is broadly consistent with the local M(BH)/Stellar Mass relation and z approximately equal 2 X-ray selected AGN. In contrast, the C-COSMOS HAEs are on average an order of magnitude less X-ray luminous and have M(BH)/SFR approximately equal (0.2-0.4) 10(exp 3), somewhat lower than the local MBH/M relation, but comparable to that found for z approximately equal 1-2 star-forming galaxies with similar mean X-ray luminosities. We estimate that a periodic QSO phase with duty cycle approximately 2%-8% would be sufficient to bring star-forming galaxies onto the local M(BH)/Stellar Mass relation. This duty cycle is broadly consistent with the observed C-COSMOS HAE AGN fraction (Approximately equal 0.4%-2.3%) for powerful AGN with LX approximately greater than 10(exp 44) erg s(exp 1). Future observations of 2QZ Clus will be needed to identify key factors responsible for driving the mutual growth of the SMBHs and galaxies
MECP2 Isoform-Specific Vectors with Regulated Expression for Rett Syndrome Gene Therapy
BACKGROUND:Rett Syndrome (RTT) is an Autism Spectrum Disorder and the leading cause of mental retardation in females. RTT is caused by mutations in the Methyl CpG-Binding Protein-2 (MECP2) gene and has no treatment. Our objective is to develop viral vectors for MECP2 gene transfer into Neural Stem Cells (NSC) and neurons suitable for gene therapy of Rett Syndrome. METHODOLOGY/PRINCIPAL FINDINGS:We generated self-inactivating (SIN) retroviral vectors with the ubiquitous EF1alpha promoter avoiding known silencer elements to escape stem-cell-specific viral silencing. High efficiency NSC infection resulted in long-term EGFP expression in transduced NSC and after differentiation into neurons. Infection with Myc-tagged MECP2-isoform-specific (E1 and E2) vectors directed MeCP2 to heterochromatin of transduced NSC and neurons. In contrast, vectors with an internal mouse Mecp2 promoter (MeP) directed restricted expression only in neurons and glia and not NSC, recapitulating the endogenous expression pattern required to avoid detrimental consequences of MECP2 ectopic expression. In differentiated NSC from adult heterozygous Mecp2(tm1.1Bird)+/- female mice, 48% of neurons expressed endogenous MeCP2 due to random inactivation of the X-linked Mecp2 gene. Retroviral MECP2 transduction with EF1alpha and MeP vectors rescued expression in 95-100% of neurons resulting in increased dendrite branching function in vitro. Insulated MECP2 isoform-specific lentiviral vectors show long-term expression in NSC and their differentiated neuronal progeny, and directly infect dissociated murine cortical neurons with high efficiency. CONCLUSIONS/SIGNIFICANCE:MeP vectors recapitulate the endogenous expression pattern of MeCP2 in neurons and glia. They have utility to study MeCP2 isoform-specific functions in vitro, and are effective gene therapy vectors for rescuing dendritic maturation of neurons in an ex vivo model of RTT
Multilevel genomics of colorectal cancers with microsatellite instability—clinical impact of JAK1 mutations and consensus molecular subtype 1
Background
Approximately 15% of primary colorectal cancers have DNA mismatch repair deficiency, causing a complex genome with thousands of small mutations—the microsatellite instability (MSI) phenotype. We investigated molecular heterogeneity and tumor immunogenicity in relation to clinical endpoints within this distinct subtype of colorectal cancers.
Methods
A total of 333 primary MSI+ colorectal tumors from multiple cohorts were analyzed by multilevel genomics and computational modeling—including mutation profiling, clonality modeling, and neoantigen prediction in a subset of the tumors, as well as gene expression profiling for consensus molecular subtypes (CMS) and immune cell infiltration.
Results
Novel, frequent frameshift mutations in four cancer-critical genes were identified by deep exome sequencing, including in CRTC1, BCL9, JAK1, and PTCH1. JAK1 loss-of-function mutations were validated with an overall frequency of 20% in Norwegian and British patients, and mutated tumors had up-regulation of transcriptional signatures associated with resistance to anti-PD-1 treatment. Clonality analyses revealed a high level of intra-tumor heterogeneity; however, this was not associated with disease progression. Among the MSI+ tumors, the total mutation load correlated with the number of predicted neoantigens (P = 4 × 10−5), but not with immune cell infiltration—this was dependent on the CMS class; MSI+ tumors in CMS1 were highly immunogenic compared to MSI+ tumors in CMS2-4. Both JAK1 mutations and CMS1 were favorable prognostic factors (hazard ratios 0.2 [0.05–0.9] and 0.4 [0.2–0.9], respectively, P = 0.03 and 0.02).
Conclusions
Multilevel genomic analyses of MSI+ colorectal cancer revealed molecular heterogeneity with clinical relevance, including tumor immunogenicity and a favorable patient outcome associated with JAK1 mutations and the transcriptomic subgroup CMS1, emphasizing the potential for prognostic stratification of this clinically important subtype.
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10.1186/s13073-017-0438-
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The contribution of X-linked coding variation to severe developmental disorders
Abstract: Over 130 X-linked genes have been robustly associated with developmental disorders, and X-linked causes have been hypothesised to underlie the higher developmental disorder rates in males. Here, we evaluate the burden of X-linked coding variation in 11,044 developmental disorder patients, and find a similar rate of X-linked causes in males and females (6.0% and 6.9%, respectively), indicating that such variants do not account for the 1.4-fold male bias. We develop an improved strategy to detect X-linked developmental disorders and identify 23 significant genes, all of which were previously known, consistent with our inference that the vast majority of the X-linked burden is in known developmental disorder-associated genes. Importantly, we estimate that, in male probands, only 13% of inherited rare missense variants in known developmental disorder-associated genes are likely to be pathogenic. Our results demonstrate that statistical analysis of large datasets can refine our understanding of modes of inheritance for individual X-linked disorders
An introduction to anticancer drugs
An introduction to anticancer drugs 24.1 Introduction 24.2 The rationale behind anticancer drug therapy 24.3 Drugs used in cancer 24.3.1 Alkylating agents 24.3.2 Cytotoxic antibiotics 24.3.3 Antimetabolites 24.3.4 Microtubule inhibitors 24.3.5 Monoclonal antibodies 24.3.6 Steroid hormones and their antagonists 24.3.7 Other treatment
Drugs affecting blood
25. Drugs affecting blood 25.1 Introduction 25.2 Important dysfunctions of the blood system 25.3 Drugs used in to correct dysfunctions of the blood 25.3.1 Anti-thrombosis treatments 25.3.1.1 Platelet aggregation inhibitors 25.3.1.2 Anticoagulants 25.3.1.3 Thrombolytics 25.3.2 Treatments for anaemia 25.3.3 Treatments for bleeding disorder
An introduction to biologics
An introduction to biologics 23.1 Introduction: Principles of biologics and their use as medicines 23.2 Protein biologics used as drugs 23.2.1 Proteins that function through enzymatic or regulatory activity. 23.2.1.1 Biologics as replacement of a deficient or abnormal protein. 23.2.1.2 Proteins that augment an existing biological process. 23.2.1.3 Proteins that provide a novel function or activity. 23.2.2. Proteins that function through specific targeting activity. 23.2.2.1. Monoclonal antibody nomenclature. 23.2.2.2. Naked monoclonal antibodies. 23.2.2.3. Conjugated monoclonal antibodies. 23.2.3. Recombinant protein vaccines