Benign prostatic hyperplasia (BPH) is a common proliferative disorder of unknown etiology. We have previously documented that the insulin-like growth factor (IGF) axis is critical for prostate cell ...growth and is abnormal in BPH. The type 1 IGF receptor (IGF-1R) is constitutively expressed by most body tissues and plays a significant role in regulating cell proliferation, consistent with the role of its ligands (IGF-I and IGF-II) as important mitogenic factors. The Wilms' tumor gene product (WT-1) is a tumor suppressor that has been shown to be altered in rare kidney tumors and is known to regulate IGF-II and IGF-1R. We investigated the possibility that the expression of prostatic WT-1, IGF-1R, and IGF-II genes is altered in patients with BPH. We utilized primary cultures of prostatic stromal cells grown from normal (n = 9) and hyperplastic (n = 9) surgical specimens and analyzed WT-1, IGF-1R, and IGF-II messenger RNA levels. In all of the BPH cell strains, WT-1 expression (measured by RT-PCR and RNase protection assays) was strikingly lower than that found in normal strains (0-20% of normal, mean 14% of normal, P < 0.01). The expression of both the IGF-1R (300% of normal, P < 0.05) and IGF-II (1000% of normal, P < 0.01) messenger RNAs was higher in BPH strains as compared with normal strains. No changes were seen in stromal cell strains derived from prostatic adenocarcinoma. Thus, in cultured human prostatic stromal cell strains from patients with BPH, decreased WT-1 gene expression is associated with increases in the expression of the IGF-1R and IGF-II genes that are known transcriptional targets of WT-1. These findings indicate that reduced expression of the WT-1 tumor suppressor gene and elevated IGF-1R and IGF-II gene expression may be involved in the pathophysiology of prostatic hyperplasia, implying a new role for the Wilms' tumor gene in nonmalignant states.
We describe the performance of a $\mathrm{23\times 23\times30 ~mm^3}$ low
background cerium bromide, CeBr$_3$(LB), scintillator crystal coupled to a
Hamamatsu R11265U-200 photomultiplier. This ...detector will be the building block
for a gamma-ray detector array designed to be the payload for a CubeSat to be
launched in 2020. The aim of the mission is to study flashes of gamma rays of
terrestrial origin. The design of the detector has been tuned for the detection
of gamma rays in the 20 keV$-$3 MeV energy range.
We describe the performance of a \(\mathrm{23\times 23\times30 ~mm^3}\) low background cerium bromide, CeBr\(_3\)(LB), scintillator crystal coupled to a Hamamatsu R11265U-200 photomultiplier. This ...detector will be the building block for a gamma-ray detector array designed to be the payload for a CubeSat to be launched in 2020. The aim of the mission is to study flashes of gamma rays of terrestrial origin. The design of the detector has been tuned for the detection of gamma rays in the 20 keV\(-\)3 MeV energy range.
Techniques which allow us to determine the series source, drain, and gate resistances and the electron saturation velocity of ion-implanted GaAs FET's are described. These techniques are based on the ..."end" resistance measurements. The theory of this method is developed and used for a new interpretation of the "end" resistance measurements. The values of the series resistances determined by this technique are shown to be in an excellent agreement with those obtained by the modified Fukui method. The values of the electron saturation velocity varying from 1.0 × 10 5 m/s to 1.3 × 10 5 m/s are obtained using the end resistance method. The proposed set of measurements is simple and accurate enough to be used as a routine characterization technique for GaAs FET's.
We propose a new interpretation of the "end" resistance measurements for field-effect transistors (FET's). This interpretation is based on the solution of the current transport equations under the ...gate and relates the "end" resistance to the source series resistance and the channel resistance of the device. The values of the series source and drain resistances determined for GaAs ion-implanted FET's, using our formulas for the "end" resistance, are in excellent agreement with the values obtained using our modification of the Fukui method 1.
Benign prostatic hyperplasia (BPH) is a common proliferative disorder
of unknown etiology. We have previously documented that the
insulin-like growth factor (IGF) axis is critical for prostate cell
...growth and is abnormal in BPH. The type 1 IGF receptor (IGF-1R) is
constitutively expressed by most body tissues and plays a significant
role in regulating cell proliferation, consistent with the role of its
ligands (IGF-I and IGF-II) as important mitogenic factors. The Wilms’
tumor gene product (WT-1) is a tumor suppressor that has been shown to
be altered in rare kidney tumors and is known to regulate IGF-II and
IGF-1R. We investigated the possibility that the expression of
prostatic WT-1, IGF-1R, and IGF-II genes is altered in patients with
BPH. We utilized primary cultures of prostatic stromal cells grown from
normal (n = 9) and hyperplastic (n = 9) surgical specimens
and analyzed WT-1, IGF-1R, and IGF-II messenger RNA levels. In all of
the BPH cell strains, WT-1 expression (measured by RT-PCR and RNase
protection assays) was strikingly lower than that found in normal
strains (0–20% of normal, mean 14% of normal, P< 0.01). The expression of both the IGF-1R (300% of normal,
P < 0.05) and IGF-II (1000% of normal,
P < 0.01) messenger RNAs was higher in BPH strains
as compared with normal strains. No changes were seen in stromal cell
strains derived from prostatic adenocarcinoma. Thus, in cultured human
prostatic stromal cell strains from patients with BPH, decreased WT-1
gene expression is associated with increases in the expression of the
IGF-1R and IGF-II genes that are known transcriptional targets of WT-1.
These findings indicate that reduced expression of the WT-1 tumor
suppressor gene and elevated IGF-1R and IGF-II gene expression may be
involved in the pathophysiology of prostatic hyperplasia, implying a
new role for the Wilms’ tumor gene in nonmalignant states.
Abstract
Computational modelling has become increasingly common in life science research. To provide a platform to support universal sharing, easy accessibility and model reproducibility, BioModels ...(https://www.ebi.ac.uk/biomodels/), a repository for mathematical models, was established in 2005. The current BioModels platform allows submission of models encoded in diverse modelling formats, including SBML, CellML, PharmML, COMBINE archive, MATLAB, Mathematica, R, Python or C++. The models submitted to BioModels are curated to verify the computational representation of the biological process and the reproducibility of the simulation results in the reference publication. The curation also involves encoding models in standard formats and annotation with controlled vocabularies following MIRIAM (minimal information required in the annotation of biochemical models) guidelines. BioModels now accepts large-scale submission of auto-generated computational models. With gradual growth in content over 15 years, BioModels currently hosts about 2000 models from the published literature. With about 800 curated models, BioModels has become the world’s largest repository of curated models and emerged as the third most used data resource after PubMed and Google Scholar among the scientists who use modelling in their research. Thus, BioModels benefits modellers by providing access to reliable and semantically enriched curated models in standard formats that are easy to share, reproduce and reuse.
Using GaAs self-aligned gate MESFETs, low-power logic circuits have been demonstrated for both depletion-mode (D-mode) Schottky-diode FET logic (SDFL) and enhancement/depletion-mode (E/D-mode) ...direct-coupled FET logic (DCFL). Propagation delays of 1.6 ns have been obtained for SDFL operating are 108 mu W per gate. DCFL has demonstrated ring-oscillator gate delays of 30 ps and speed-power products as low as 1.1 fJ per gate. A 2K-cell gate array designed with low-power SDFL has demonstrated an 8-bit adder with an add time of 11 ns at 236 mW. Automatic software was used for the placement and routine of the 8-bit adder in the gate array. DCFL divide-by-four circuits designed for 500-MHz operation have demonstrated up to 2.5-GHz operation with a power dissipation of 172 mu W per gate at 1-GHz clock frequency. DCFL divide-by-four circuits subjected to 3.4*10/sup 7/ rads (Si) and 1*10/sup 14/ N/cm/sup 2/, for total dose and neutron fluence, respectively, have demonstrated only minimal reduction in power and no degradation of circuit performance.< >
Describes a GaAs gate array with on-chip RAM based on the Schottky diode field-effect transistor logic (SDFL) technology. The array features 432 programmable SDFL cells, 32 programmable interface ...input-output (I/O) buffers, and four 4/spl times/4 bit static random access memories (RAM) on a 147 mil/spl times/185 mil chip. Each SDFL cell can be programmed as a NOR gate with as many as 8 inputs with a buffered or unbuffered output or as a dual OR-NAND gate with four inputs per side. The interface I/O buffer can be programmed for ECL, TTL, CMOS, and SDFL logic families. Each 4/spl times/4 bit RAM is fully decoded using SDFL circuits (depletion-mode MESFET). Preliminary results demonstrate the feasibility of GaAs SDFL for fast gate array and memory applications.
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