25,714 research outputs found
Intracerebral transplantation of neural stem cells combined with trehalose ingestion alleviates pathology in a mouse model of Huntington’s disease.
No full textDecoy receptor 3 expression in AsPC-1 human pancreatic adenocarcinoma cells via the phosphatidylinositol 3-kinase-, Akt-, and NF-kappaB-dependent pathway
No full textProtein expression on Cr resistant microorganism using electrophoresis method
Full text linkAbstrak. Fatmawati U, Suranto, Sajidan. 2009. Ekspresi protein pada mikroorganisme resisten Cr dengan metode elektroforesis.
Nusantara Bioscience 1: 31-37. Krom heksavalen (Cr(VI)) dikenal sebagai logam berat beracun, sehingga perlu direduksi menjadi
Cr(III) yang lebih rendah toksisitasnya. Pseudomonas aeruginosa, Pseudomonas putida, Klebsiella pneumoniae, Pantoea sp. dan
Saccharomyces cerevisiae adalah mikroorganisme resisten dan mampu mereduksi Cr(VI). Tujuan penelitian ini adalah mengetahui
kemampuan mikroorganisme dalam mengurangi Cr(VI) dan mengetahui pola pita protein antara mikroorganisme resisten Cr(VI) dan
mikroorganisme tidak resisten yang diinokulasi pada medium kaldu LB. SDS-PAGE digunakan untuk mengetahui ekspresi protein,
sementara konsentrasi Cr(VI) diidentifikasi dengan metode 1,5 difenilkarbazid. Data kuantitatif dianalisis dengan ANAVA dua faktorial
dilanjutkan dengan uji jarak berganda Duncan pada taraf 1%. Data kualitatif yaitu ekspresi protein dianalisis dengan mobilitas relatif
(Rf). Hasil penelitian menunjukkan bahwa kemampuan mikroorganisme dalam mereduksi Cr(VI) pada konsentrasi awal 0.5 ppm, 1 ppm,
5 ppm dan 10 ppm berbeda-beda, persentase rata-rata kemampuan masing-masing mikroorganisme dalam mereduksi Cr(VI) adalah: P.
putida (65%) > S. cerevisiae (64,45%) > P. aeruginosa (60,73%) > Pantoea sp. (50,22%) > K. pneumoniae (47,82%) > tanpa
mikroorganisme (34,25%). Penambahan mikroorganisme secara nyata mempengaruhi reduksi Cr(VI). SDS-PAGE menunjukkan bahwa
ekspresi protein antara mikroorganisme resisten dan tidak resisten tidak berbeda, tetapi mikroorganisme resisten memiliki lebih banyak
protein (pita protein lebih tebal).
Kata kunci: logam berat Cr, mikroorganisme, protein, elektroforesis
Phytoextraction of Cr(VI) from soil using Portulaca oleracea
No full textCr(VI) represents an environmental challenge in both soil and water as it is soluble and bioavailable over a wide range of pH. In previous investigations, Portulaca oleracea (a plant local to the United Arab Emirates (UAE)) demonstrated particular ability for the phytoextraction of Cr(VI) from calcareous soil of the UAE. In this publication, the results of the evaluation of P. oleracea phytoextraction of Cr(VI) from UAE soil at higher concentrations are reported. P. oleracea was exposed to nine different concentrations of Cr(VI) in soil from 0 to 400 mg kg−1. The uptake of Cr(VI) increased as its concentration in soil increased between 50 and 400 mg kg−1, with the most efficient removal in the range from 150 to 200 mg kg−1. The total chromium concentrations exceeded 4600 mg kg−1 in roots and 1400 mg kg−1 in stems, confirming the role of P. oleracea as an effective Cr(VI) accumulator. More than 95% of the accumulated Cr(VI) was reduced to the less toxic Cr(III) within the plant
Reduced scapular muscle control and impaired shoulder joint position sense in subjects with chronic shoulder stiffness. 英
No full textStructural variation of the needle leaves of Pinus taiwanensis Hay. along an altitudinal gradient.
No full textANALISIS PENGARUH REFERENCE PRICE DAN ACTUAL PRICE TERHADAP PERCEIVED VALUE DAN WILLINGNESS TO BUY (Studi pada Promo Diskon 50% Produk Fashion Matahari Department Store di Kota Surakarta )
Full text linkPenelitian ini bertujuan untuk mengetahui : (1) Apakah reference price
berpengaruh positif terhadap perceived quality? (2) Apakah actual price berpengaruh
positif terhadap perceived sacrifice? (3) Apakah perceived quality berpengaruh
positif terhadap perceived value? (4) Apakah perceived sacrifice berpengaruh negatif
terhadap perceived value? (5) Apakah perceived value berpengaruh positif terhadap
willingness to buy? (6) Apakah redemption effort berpengaruh negatif terhadap
perceived value?
Responden penelitian ini adalah 195 pelanggan Matahari Department Store
di Kota Surakarta. Pengumpulan data dengan menggunakan metode kuesioner.
Pengambilan sampel dilakukan dengan non probability sampling dengan metode
purposive sampling berdasarkan kriteria : mengetahui promo diskon 50%, pernah
melakukan pembelian, berusia lebih dari 18 tahun dan pendidikan minimal SMA.
Model ini diuji dengan menggunakan metode SEM (Structural Equation Modeling)
dengan bantuan program AMOS versi 7.0.
Hasil analisis menunjukkan bahwa besarnya nilai indeks Goodness of fit
adalah: Chi-square = 173.958, probability level = 0.088, df = 150, CMIN/DF =
1.160, GFI = 0.924, AGFI = 0.893, TLI = 0.977, CFI = 0.982 dan RMSEA = 0.029.
Estimasi parameter menunjukkan bahwa jalur analisis yang memiliki CR lebih besar
dari +1,96 pada signifikansi 5% adalah (1) pengaruh perceived quality terhadap
perceived value, (2) pengaruh redemption effort terhadap perceived value, (3)
pengaruh perceived value terhadap willingness to buy. Sedangkan pengaruh antara
harga terhadap perceived sacrifice dan perceived quality serta pengaruh antara
perceived sacrifice terhadap perceived value didapatkan hasil nilai CR kurang dari
+1,96 pada signifikansi 5% sehingga harga tidak berpengaruh signifikan terhadap
perceived sacrifice dan perceived quality serta perceived sacrifice tidak berpengaruh
pada perceived value.Berdasarkan hasil penelitian tersebut, apabila perusahaan ingin
meningkatkan willingness to buy dari konsumen, maka dapat dilakukan dengan cara
menurunkan redemption effort dan meningkatkan perceived quality yang terbentuk
dari faktor non-harga. Pada penelitian ini potongan harga 50% tidak mempengaruhi
penurunan perceived sacrifice dan peningkatan perceived value
SYNTHESIS OF POLY- TETRA-p-ALLYLCALIX[4]ARENE TETRA ACETIC ACID ADSORBENT FOR Cr(III) AND Pb(II) METAL IONS
Full text linkThis paper discusses the preparation, characterization, and the evaluation of adsorption
properties of resin poly-tetra-p-allylcalix[4]arene tetra acetic acid from the p-t-butylphenol. The
synthesized resins were applied as an adsorbent for Cr(III) and Pb(II) metal ions. The
adsorption was conducted in a batch system by investigating the effects of acidity (pH), contact
time and initial concentration of a heavy metal solution. The adsorption of Cr(III) and Pb(II)
metal ions on the resin had the optimum pH rating in region of 4–6 and reached the equilibrium
condition in 40 minutes. The adsorption of Cr(III) and Pb(II) metal ions on the resin follows the
Langmuir isothermal pattern with the linearity constant (R2
) of Cr(III) and Pb(II) adsorption,
whose results were 0.9640 and 0.9716, respectively. The adsorption capacity of Cr(III) and
Pb(II) metal ions is 323.0 µmole/g and 33.4 µmole/g , while the adsorption energy is 30.4
kJ/mole and 39.7 kJ/mole, respectively. Most parameters in batch systems confirm that resin is
a good adsorbent for Cr(III) and Pb(II), though Cr(III) adsorption was more favorable than that
of Pb(II). The outstanding adsorption abilities for Cr(III) and Pb(II) metal ions have exhibited
good prospects for disposal application of polluted water and environmental protection.
Keywords: Adsorption; Metal ions; Poly-tetra-p-allylcalix[4]arene tetra acetic acid; p-t-
butylpheno
Regulation of Cr(VI)-Induced Premature Senescence in L02 Hepatocytes by ROS-Ca2+-NF-κB Signaling
No full textStress-induced premature senescence may be involved in the pathogeneses of acute liver injury. Hexavalent chromium [Cr(VI)], a common environmental pollutant related to liver injury, likely leads to premature senescence in L02 hepatocytes. However, the underlying mechanisms regarding hepatocyte premature senility in Cr(VI) exposure remain poorly understood. In this study, we found that chronic exposure of L02 hepatocytes to Cr(VI) led to premature senescence characterized by increased β-galactosidase activity, senescence-associated heterochromatin foci, G1 phase arrest, and decreased cell proliferation. Additionally, Cr(VI)-induced senescent L02 hepatocytes showed upregulated inflammation-related factors, such as IL-6 and fibroblast growth factor 23 (FGF23), which also exhibited reactive oxygen species (ROS) accumulation derived from mitochondria accompanied with increased concentration of intracellular calcium ions (Ca2+) and activity of nuclear factor kappa B (NF-κB). Of note is that ROS inhibition by N-acetyl-Lcysteine pretreatment not only alleviated Cr(VI)-induced premature senescence but also reduced the elevated intracellular Ca2+, activated NF-κB, and secretion of IL-6/FGF23. Intriguingly, the toxic effect of Cr(VI) upon premature senescence of L02 hepatocytes and increased levels of IL-6/FGF23 could be partially reversed by the intracellular Ca2+ chelator BAPTA-AM pretreatment. Furthermore, by utilizing the NF-κB inhibitor pyrrolidine dithiocarbamate (PDTC), we confirmed that NF-κB mediated IL-6/FGF23 to regulate the Cr(VI)-induced L02 hepatocyte premature senescence, whilst the concentration of intracellular Ca2+ was not influenced by PDTC. To the best of our knowledge, our data reports for the first time the role of ROS-Ca2+-NF-κB signaling pathway in Cr(VI)-induced premature senescence. Our results collectively shed light on further exploration of innovative intervention strategies and treatment targeting Cr(VI)-induced chronic liver damage related to premature senescence.Full Tex
High magnetoresistance in ultra-thin two-dimensional Cr-based MXenes
No full textDeveloping effective magnetoresistance devices has become beneficial due to their extensive applications in electronics such as data storage. One challenge is to reduce the scale of devices while maintaining a high magnetoresistance. Another challenge for the applications of magnetoresistance devices involves synthesizing them with stable interfaces. Antiferromagnetic Cr-based MXenes are similar to tunneling magnetoresistance junctions, and can be synthesized in a straightforward manner. Density functional theory calculations show that the medium adhesion strength between Au electrodes and Cr-based MXene can ensure the formation of stable interfaces. Exchange coupling between Cr atoms in different atomic layers is found to decrease to 0.4 meV with increasing thickness. Magnetoresistance values are higher than 400% with 1.0 V. The results show that Cr-based MXenes are promising magnetoresistance devices with high magnetoresistance values and ultra-thin layers (about 1 nm) and exhibit tunable exchange coupling between Cr atoms through thickness control
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