Department of Physiology and Biophysics, University of Louisville School of Medicine, Louisville, Kentucky
Submitted 15 November 2004
; accepted in final form 26 January 2005
We examined the ...hypothesis that oxidants generated nitroso derivatives, activated latent matrix metalloproteinase (MMP), and induced proteinase-activated receptor 1 (PAR-1), leading to disconnection between the endothelium and myocytes. Administration of cardiospecific tissue inhibitor of metalloproteinase-4 (TIMP-4/CIMP) ameliorated the oxidative-proteolytic stress and endothelial-myocyte uncoupling in chronic heart failure (CHF) in mice. Aortic-vena cava fistula (AVF) was created in 30 male mice (C57BL/6J) and studied at 0-, 2-, and 8-wk AVF. To reverse cardiac remodeling, as measured by MMP activation, purified CIMP was administered by an osmotic minipump subcutaneously after 8-wk AVF, and groups of mice ( n = 6 mice/group) were examined after 12 and 16 wk. Levels of PAR-1 in the left ventricle (LV) were increased at 2 and 8 wk (compared with 0 wk of no CIMP treatment) but were normal at 12 and 16 wk after CIMP treatment, as measured by Western blot analysis. Similar results were obtained for LV levels of nitrotyrosine, MMP-2 and -9 activities, and TIMP-1 and -3. However, the levels of TIMP-4, endothelial cell density, and responses of cardiac rings to acetylcholine and bradykinin were attenuated at 2 and 8 wk and normalized after CIMP administration in AVF mice. CIMP induced nitric oxide in microvascular endocardial endothelial cells. The results suggest that nitro generation activated MMP and PAR-1, leading to endothelial-myocyte uncoupling. CIMP treatment normalized PAR-1 expression and ameliorated endothelial-myocyte uncoupling by decreasing oxidant-mediated proteolytic stress in CHF.
proteomics; shedding; nitric oxide; NADPH oxidase; cardiac ring; contraction; relaxation; dilatation; matrix metalloproteinase; nitrotyrosine; tissue inhibitors of metalloproteinase; coupling
Address for reprint requests and other correspondence: S. C. Tyagi, Univ. of Louisville School of Medicine, A-1115, Dept. of Physiology and Biophysics, 500 S. Preston St., Louisville, KY 40202 (E-mail: s0tyag01{at}louisville.edu )
Synthetic biology also termed as "genomic alchemy" represents a powerful area of science that is based on the convergence of biological sciences with systems engineering. It has been fittingly ...described as "moving from reading the genetic code to writing it" as it focuses on building, modeling, designing and fabricating novel biological systems using customized gene components that result in artificially created genetic circuitry. The scientifically compelling idea of the technological manipulation of life has been advocated since long time. Realization of this idea has gained momentum with development of high speed automation and the falling cost of gene sequencing and synthesis following the completion of the human genome project. Synthetic biology will certainly be instrumental in shaping the development of varying areas ranging from biomedicine, biopharmaceuticals, chemical production, food and dairy quality monitoring, packaging, and storage of food and dairy products, bioremediation and bioenergy production, etc. However, potential dangers of using synthetic life forms have to be acknowledged and adoption of policies by the scientific community to ensure safe practice while making important advancements in the ever expanding field of synthetic biology is to be fully supported and implemented.
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BFBNIB, GIS, IJS, KISLJ, NUK, PNG, UL, UM, UPUK
The SPX gene family, ubiquitous in all vascular plants, plays a critical role in plant development and growth as well as in response to phosphorus stress. Based on genomic census, 46 TaSPX genes were ...identified in the wheat genome. All of them are evenly distributed on 13 of the 21 wheat chromosomes and chromosome 7A contains the largest members. As many as 57 gene specific SSRs were discovered among genomic sequences of identified TaSPXs. MicroRNA target analysis revealed that TaSPX genes were targeted by 9 different miRNAs including tae-miR1120a, tae-miR1120b-3p, tae-miR1120c-5p, tae-miR1122b-3p, tae-miR1122c-3p, tae-miR1130a, tae-miR1130b-3p, tae-miR1137a, and tae-miR1137b-5p. Expression profiles derived from transcriptome data and real-time quantitative PCR revealed that TaSPX genes were significantly induced by Pi starvation. The modeled 3D structure of wheat SPX proteins shared high level of homology with template structures, providing information to understand their functions at proteomic level. We have also refined the modeled 3D structures on 10 ns using molecular dynamics simulations for conformational stability. The discovered members of SPX gene family and their targeting miRNAs may provide resource for genetic improvement and promote P use efficiency in cereals.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
The objective of the study was to evaluate the effect of vitamin E and Se supplementation on oxidative markers and semen quality parameters in breeding bulls. The study was conducted at ICAR-Central ...Institute for Research on Cattle, Meerut (subtropical climate), Uttar Pradesh during 2019. Eighteen bulls (six good bulls and twelve poor bulls) were divided into three groups consisting 6 bulls in each. Six good bulls of group 1 served as healthy control. Group 2 poor bulls were administered Vitamin E and Selenium @ 10 ml SC (Vitamin E 50 mg as DL-α-tocopheryl acetate and Selenium 15 mg as sodium selenite) once weekly for three weeks while group 3 poor bulls were kept as untreated control. Semen samples were collected and semen quality and biochemical parameters were done using standard procedures at fortnightly interval upto two months. Significantly low MDA and higher SOD and catalase were observed in bulls of supplemented group. Semen volume, sperm concentration, initial motility, percentage of live sperm and hypo-osmotic swelling test improved significantly in supplemented group as compared to nonsupplemented bulls. The study concludes that supplementation of vitamin E and Se causes significant improvement in oxidative stress markers and semen quality parameters in breeding bulls.
•Explored the linear and nonlinear optical interaction in the Bi2Se3 single-crystal cleaved flake.•Kramer’s Kronig approach and DFT calculations confirm the prominent 2 eV OBT from the Ɛ1 and Ɛ2 ...simulations.•Concurrently, the TRUS measurements are done to explore the excited-state dynamics of the states populating due to the Moss-Burstein shifts.•With the same excitation, probing in the NIR region shows the occurrence of the Pauli blocking.•The low temperature study give a clear evidence of presence of second surface state and a broad absorbance of 1.2 eV can be easily seen through TRUS.
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We report the optical response and temperature-dependent excited-state carrier dynamics in the flake of Bi2Se3, which is cleaved from its single crystal. The optical properties are explored using the visible-near infrared (VIS-NIR), infrared (IR), and photoluminescence (PL) spectroscopies. The VIS-NIR spectra are then used to find the Ɛ1 and Ɛ2 using Kramer’s Koning relations, confirming OBT of 2 eV and 1.4 eV. The DFT (density functional theory) calculations are also carried out to confirm the experimental optical transitions (OBT). To probe these OBT in the bismuth selenide, we have studied the temperature, fluence, and excitation dependent ultrafast transient reflectance over a wide spectral range from 2.58–0.77 eV (VIS-NIR) with different excitation energies 3.02 eV, 2.61 eV, 1.9 eV, and 1.4 eV to explore several previously unseen transitions that do not appear in PL spectroscopy and room temperature carrier analysis. The temperature-dependent excited-state dynamics are investigated at 5–300 K. This study clearly indicates the existence of Moss-Burstein shift in the visible region and Pauli blocking effect in the NIR region in the Bi2Se3 topological insulator. Moreover, the low-temperature TRUS confirms the transition to the second surface state present in bismuth selenide.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Damage caused by swift heavy ions with three different electronic stopping powers (120
MeV Au
9+ (22
keV/nm), 90 MeV I
7+ (17
keV/nm) and 70
MeV Ni
5+ (11
keV/nm)) in three pyrochlores (Gd
2Zr
2O
7, ...Nd
2Zr
2O
7 and Gd
2Ti
2O
7) with progressively increasing radius ratios (
r
A/
r
B of A
2B
2O
7) of cations is reported. Since I
+7 is one of the ions used, these measurements also simulate fission fragment damage in pyrochlores and identify a potential host lattice for inert matrix fuel. X-ray diffraction on the irradiated materials indicate amorphization in Gd
2Ti
2O
7 at the lowest
S
e used, and a transition to anion-deficient fluorite (
Fm
3
¯
m
) structure with about 1% decrease in volume in Nd
2Zr
2O
7 and Gd
2Zr
2O
7 at higher
S
e. In Nd
2Zr
2O
7 this is followed by amorphization and Gd
2Zr
2O
7 does not amorphize even at the highest
S
e employed. Raman analysis of Gd
2Zr
2O
7 and Nd
2Zr
2O
7, indicate an increase of Zr coordination number after irradiation and the bands become broader due to disordering. Analysis of the results shows that the radiation susceptibility of these pyrochlores in the electronic stopping regime strongly depends on the radius ratio of A to B cations and hence on the energy required for formation of cation antisites and anion Frenkel pairs, similar to their susceptibility in the nuclear stopping regime.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
The development of a short-wavelength p-n junction device is essentially important for the realization of transparent electronics for next-generation optoelectronics. Nickel oxide (NiO) thin films ...with a tunable electrical conductivity of both p-type and n-type under the optimized growth conditions using RF sputtering technique with high optical transmission in the visible region have been fabricated. The room-temperature conductivities for n-type and p-type NiO thin films were about 5.91 × 10 1 and 1.9 ×10 -2 S·cm -1 , respectively. A p-n junction of NiO thin film has been realized, successfully exhibiting good rectifying behavior with efficient UV photodiode characteristics, providing suitable solution for low-cost visible blind UV photodetector application.
A new in-situ plasma processing technique is being developed at the Spallation Neutron Source (SNS) to improve the performance of the cavities in operation. The technique utilizes a low-density ...reactive oxygen plasma at room temperature to remove top surface hydrocarbons. The plasma processing technique increases the work function of the cavity surface and reduces the overall amount of vacuum and electron activity during cavity operation; in particular it increases the field emission onset, which enables cavity operation at higher accelerating gradients. Experimental evidence also suggests that the SEY of the Nb surface decreases after plasma processing which helps mitigating multipacting issues. In this article, the main developments and results from the plasma processing R&D are presented and experimental results for in-situ plasma processing of dressed cavities in the SNS horizontal test apparatus are discussed.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
Abstract
A study of a silicon photomultiplier (SiPM) coupled with a
GGAG:Ce,B scintillator detector for environmental gamma radiation
monitoring is presented in this paper. FLUKA based Monte Carlo
...simulations were carried out for the optimization of scintillator
material and geometry for this application. Based on the simulation
study, the dimensions of GGAG:Ce,B scintillator crystal were
finalized and the scintillator was prepared. The detector was
assembled by optically coupling to a commercially available
SiPM. The analog output pulses of the SiPM were amplified by a
voltage sensitive amplifier and subsequently counted using a
microcontroller. The linearity of the detector response with gamma
dose rate was verified using
137
Cs standard gamma source. The
radiation response of the detector for different gamma energies was
investigated using standard
137
Cs,
241
Am and
60
Co
sources. The variation of detector sensitivity with SiPM overvoltage
was measured for choosing an optimal overvoltage for the SiPM
operation. The experimentally observed response of the
SiPM-GGAG:Ce,B detector was very linear in the measurement range of
3.5–300 μGy/h with a sensitivity of
2.44 cps/μGy/h. The gamma response study of the detector
confirm the suitability of the developed detector for making a
compact and low power gamma monitor for environmental gamma
radiation monitoring network.
Blumeria graminis (DC). E.U. Speer f.sp. tritici Em. Marchal (Syn. Erysiphe graminis DC f.sp. tritici, Em. Marchal), a causal organism of powdery mildew (PM), is one of the important diseases of ...wheat worldwide. A comprehensive evaluation of wheat germplasm accessions (19,460) conserved in the National Genebank of ICAR–National Bureau of Plant Genetic Resources was conducted to identify sources of resistance to PM. Accessions belonging to the three wheat species—bread wheat (Triticum aestivum L. subsp. aestivum) (15,944), durum wheat (T. durum Desf.) (3,359), and emmer wheat (T. dicoccum Schrank ex Schübl.) (157)—were screened at Wellington, a hotspot location for PM, for two consecutive seasons. Screening results indicated that 7271 (45%) from bread wheat, 756 (22%) from durum wheat, and 22 (14%) from emmer were resistant. Out of 8094 PM‐resistant accessions, 60% were indigenous, while majority of the 40% exotic were from CIMMYT. Focused identification of germplasm strategy (FIGS), which identifies a set of similar plant genotypes with a greater possibility of containing specific target traits, was used to form a subset of 52 accessions (from 19,460) that have the potential to contain new PM resistance genes. Resistant accessions identified in the study have enriched the existing gene pool for PM resistance in wheat and will serve as a potential source for resistance in future.
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FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
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