148 research outputs found
Species D human adenovirus type 9 exhibits better virus-spread ability for antitumor efficacy among alternative serotypes
Species C human adenovirus serotype 5 (HAdV-C5) is widely used as a vector for cancer gene therapy, because it efficiently transduces target cells. A variety of HAdV-C5 vectors have been developed and tested in vitro and in vivo for cancer gene therapy. While clinical trials with HAdV-C5 vectors resulted in effective responses in many cancer patients, administration of HAdV-C5 vectors to solid tumors showed responses in a limited area. A biological barrier in tumor mass is considered to hinder viral spread of HAdV-C5 vectors from infected cells. Therefore, efficient virus-spread from an infected tumor cell to surrounding tumor cells is required for successful cancer gene therapy. In this study, we compared HAdV-C5 to sixteen other HAdV serotypes selected from species A to G for virus-spread ability in vitro. HAdV-D9 showed better virus-spread ability than other serotypes, and its viral progeny were efficiently released from infected cells during viral replication. Although the HAdV-D9 fiber protein contains a binding site for coxsackie B virus and adenovirus receptor (CAR), HAdV-D9 showed expanded tropism for infection due to human CAR (hCAR)-independent attachment to target cells. HAdV-D9 infection effectively killed hCAR-negative cancer cells as well as hCAR-positive cancer cells. These results suggest that HADV-D9, with its better virus-spread ability, could have improved therapeutic efficacy in solid tumors compared to HAdV-C5
A multi targeting conditionally replicating adenovirus displays enhanced oncolysis while maintaining expression of immunotherapeutic agents
Studies have demonstrated that oncolytic adenoviruses based on a 24 base pair deletion in the viral E1A gene (D24) may be promising therapeutics for treating a number of cancer types. In order to increase the therapeutic potential of these oncolytic viruses, a novel conditionally replicating adenovirus targeting multiple receptors upregulated on tumors was generated by incorporating an Ad5/3 fiber with a carboxyl terminus RGD ligand. The virus displayed full cytopathic effect in all tumor lines assayed at low titers with improved cytotoxicity over Ad5-RGD D24, Ad5/3 D24 and an HSV oncolytic virus. The virus was then engineered to deliver immunotherapeutic agents such as GM-CSF while maintaining enhanced heterogenic oncolysis
X-ray Properties of the Weak Seyfert 1 Nucleus in NGC 4639
We obtained observations of NGC 4639 with ASCA in order to investigate its
mildly active Seyfert 1 nucleus at hard X-ray energies. Koratkar et al. (1995)
have previously shown that the nucleus is a pointlike source in the ROSAT soft
X-ray band. We detected in the 2-10 keV band a compact central source with a
luminosity of 8.3E+40 erg/s. Comparison of the ASCA data with archival data
taken with the Einstein and ROSAT satellites shows that the nucleus varies on
timescales of months to years. The variability could be intrinsic, or it could
be caused by variable absorption. More rapid variability, on a timescale of
\~10^4 s, may be present in the ASCA data. The spectrum from 0.5 to 10 keV is
well described by a model consisting of a lightly absorbed (N_H = 7.3E+20
cm^-2) power law with a photon index of 1.68. We find no evidence for
significant emission from a thermal plasma; if present, it can account for no
more than 25% of the flux in the 0.5-2.0 keV band. The limited photon
statistics of our data do not allow us to place significant limits on the
presence of iron K emission. (abridged)Comment: To appear in The Astrophysical Journal. LaTex, 18 pages including
embedded figures and table
Detection of an iron K Emission Line from the LINER NGC 4579
We present the results of an ASCA observation of the LINER NGC 4579. A
point-like X-ray source is detected at the nucleus with a 2-10 keV luminosity
of 1.5x10^41 ergs/s assuming a distance of 16.8 Mpc. The X-ray spectrum is
represented by a combination of a power-law with a photon index of ~1.7 and
soft thermal component with kT~0.9 keV. An iron K emission line is detected at
6.73+/-0.13 keV (rest frame) with an equivalent width of 490 +180/-190 eV and
is statistically significant at more than 99.9 % confidence. The line center
energy is consistent with Helium-like iron and is significantly higher than 6.4
keV which is expected from fluorescence by "cold" (or a lower ionization state
of) iron. The iron line profile shows no significant red tail in contrast to
Seyfert 1 galaxies although the statistics are limited. The line center energy,
equivalent width, and profile are consistent with an origin in an ionized
accretion disk. However the large mass accretion rate necessary to ionize the
accretion disk is not consistent with the observed luminosity and normal
accretion models.Comment: 15 pages, 5 figures, to appear in The Astrophysical Journa
Evaluation of adenovirus capsid labeling versus transgene expression
Adenoviral vectors have been utilized for a variety of gene therapy applications. Our group has incorporated bioluminescent, fluorographic reporters, and/or suicide genes within the adenovirus genome for analytical and/or therapeutic purposes. These molecules have also been incorporated as capsid components. Recognizing that incorporations at either locale yield potential advantages and disadvantages, our report evaluates the benefits of transgene incorporation versus capsid incorporation. To this end, we have genetically incorporated firefly luciferase within the early region 3 or at minor capsid protein IX and compared vector functionality by means of reporter readout
Lung of Fgf10-CRISPR mosaic mouse
CRISPR/Cas9-mediated gene editing often generates founder generation (F0) mice that exhibit somatic mosaicism in the targeted gene(s). It has been known that Fibroblast growth factor 10 (Fgf10)-null mice exhibit limbless and lungless phenotypes, while intermediate limb phenotypes (variable defective limbs) are observed in the Fgf10-CRISPR F0 mice. However, how the lung phenotype in the Fgf10-mosaic mutants is related to the limb phenotype and genotype has not been investigated. In this study, we examined variable lung phenotypes in the Fgf10-targeted F0 mice to determine if the lung phenotype was correlated with percentage of functional Fgf10 genotypes. Firstly, according to a previous report, Fgf10-CRISPR F0 embryos on embryonic day 16.5 (E16.5) were classified into three types: type I, no limb; type II, limb defect; and type III, normal limbs. Cartilage and bone staining showed that limb truncations were observed in the girdle, (type I), stylopodial, or zeugopodial region (type II). Deep sequencing of the Fgf10-mutant genomes revealed that the mean proportion of codons that encode putative functional FGF10 was 8.3 ± 6.2% in type I, 25.3 ± 2.7% in type II, and 54.3 ± 9.5% in type III (mean ± standard error of the mean) mutants at E16.5. Histological studies showed that almost all lung lobes were absent in type I embryos. The accessory lung lobe was often absent in type II embryos with other lobes dysplastic. All lung lobes formed in type III embryos. The number of terminal tubules was significantly lower in type I and II embryos, but unchanged in type III embryos. To identify alveolar type 2 epithelial (AECII) cells, known to be reduced in the Fgf10-heterozygous mutant, immunostaining using anti-surfactant protein C (SPC) antibody was performed: In the E18.5 lungs, the number of AECII was correlated to the percentage of functional Fgf10 genotypes. These data suggest the Fgf10 gene dose-related loss of the accessory lobe and decrease in the number of alveolar type 2 epithelial cells in mouse lung. Since dysfunction of AECII cells has been implicated in the pathogenesis of parenchymal lung diseases, the Fgf10-CRISPR F0 mouse would present an ideal experimental system to explore it
ASCA Observations of "Type 2" LINERs: Evidence for a Stellar Source of Ionization
We present ASCA observations of LINERs without broad H emission in
their optical spectra. The sample of "type 2" LINERs consists of NGC 404, 4111,
4192, 4457, and 4569. We have detected X-ray emission from all the objects
except for NGC 404; among the detected objects are two so-called transition
objects (NGC 4192 and NGC 4569), which have been postulated to be composite
nuclei having both an HII region and a LINER component. The images of NGC 4111
and NGC 4569 in the soft (0.5-2 keV) and hard (2-7 keV) X-ray bands are
extended on scales of several kpc. The X-ray spectra of NGC 4111, NGC 4457 and
NGC 4569 are well fitted by a two-component model that consists of soft thermal
emission with keV and a hard component represented by a power law
(photon index 2) or by thermal bremsstrahlung emission ( several
keV). The extended hard X-rays probably come from discrete sources, while the
soft emission most likely originates from hot gas produced by active star
formation in the host galaxy. We have found no clear evidence for the presence
of active galactic nuclei (AGNs) in the sample. If an AGN component is the
primary ionization source of the optical emission lines, then it must be
heavily obscured with a column density significantly larger than
cm. Alternatively, the optical emission could be ionized by a population
of exceptionally hot stars.Comment: 13 pages, 5 figures, emulateapj.sty, Accepted for publication in the
Astrophysical Journa
Fgf10-CRISPR mosaic mutants demonstrate the gene dose-related loss of the accessory lobe and decrease in the number of alveolar type 2 epithelial cells in mouse lung
CRISPR/Cas9-mediated gene editing often generates founder generation (F0) mice that exhibit somatic mosaicism in the targeted gene(s). It has been known thatFibroblast growth factor 10(Fgf10)-null mice exhibit limbless and lungless phenotypes, while intermediate limb phenotypes (variable defective limbs) are observed in theFgf10-CRISPR F0 mice. However, how the lung phenotype in theFgf10-mosaic mutants is related to the limb phenotype and genotype has not been investigated. In this study, we examined variable lung phenotypes in theFgf10-targeted F0 mice to determine if the lung phenotype was correlated with percentage of functionalFgf10genotypes. Firstly, according to a previous report,Fgf10-CRISPR F0 embryos on embryonic day 16.5 (E16.5) were classified into three types: type I, no limb; type II, limb defect; and type III, normal limbs. Cartilage and bone staining showed that limb truncations were observed in the girdle, (type I), stylopodial, or zeugopodial region (type II). Deep sequencing of theFgf10-mutant genomes revealed that the mean proportion of codons that encode putative functional FGF10 was 8.3 +/- 6.2% in type I, 25.3 +/- 2.7% in type II, and 54.3 +/- 9.5% in type III (mean +/- standard error of the mean) mutants at E16.5. Histological studies showed that almost all lung lobes were absent in type I embryos. The accessory lung lobe was often absent in type II embryos with other lobes dysplastic. All lung lobes formed in type III embryos. The number of terminal tubules was significantly lower in type I and II embryos, but unchanged in type III embryos. To identify alveolar type 2 epithelial (AECII) cells, known to be reduced in theFgf10-heterozygous mutant, immunostaining using anti-surfactant protein C (SPC) antibody was performed: In the E18.5 lungs, the number of AECII was correlated to the percentage of functionalFgf10genotypes. These data suggest theFgf10gene dose-related loss of the accessory lobe and decrease in the number of alveolar type 2 epithelial cells in mouse lung. Since dysfunction of AECII cells has been implicated in the pathogenesis of parenchymal lung diseases, theFgf10-CRISPR F0 mouse would present an ideal experimental system to explore it
The Type Ic Hypernova SN 2002ap
Photometric and spectroscopic data of the energetic Type Ic supernova (SN)
2002ap are presented, and the properties of the SN are investigated through
models of its spectral evolution and its light curve. The SN is
spectroscopically similar to the "hypernova" SN 1997ef. However, its kinetic
energy [ erg] and the mass ejected (2.5-5
) are smaller, resulting in a faster-evolving light curve. The SN
synthesized of Ni, and its peak luminosity was
similar to that of normal SNe. Brightness alone should not be used to define a
hypernova, whose defining character, namely very broad spectral features, is
the result of a high kinetic energy. The likely main-sequence mass of the
progenitor star was 20-25 , which is also lower than that of both
hypernovae SNe 1997ef and 1998bw. SN 2002ap appears to lie at the low-energy
and low-mass end of the hypernova sequence as it is known so far. Observations
of the nebular spectrum, which is expected to dominate by summer 2002, are
necessary to confirm these values.Comment: 10 pages, 4 figures, accepted for publication in ApJL, 30 April 2002
(minor changes to match the accepted version, with figures being colored
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