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Superroxide dismutase (SOD, EC.1.15.1.1) is the enzyme which dismutates superoxide radicals and plays an important role in protection of living cells against oxidative stress. SOD is also involved in immune response in shrimps. In this study, it was found that the total SOD activity of black tiger shrimp muscular tissues is 10 fold higher than that of the haemolymph, however, the specific activity of SOD in the shrimp haemolymph is 9.2 fold higher than that of muscular tissues. By using active gel electrophoresis, 2 different SOD forms were found in black tiger shrimps (one in muscular tissues and two in haemolymph).Using DE-52 cellulose and Q-Sepharose ion exchange column chromatography, one SOD (SOD1) from black tiger shrimp haemolymph was partially purified, and its purity was 31.2 times higher than that of the starting haemolymph. The SOD1 was shown to have mainly one protein band of approximately 24 kDa on SDS-PAGE. SOD1 was most active at 45oC and pH of 5.5. At a concentration of 5 mM, Mn2+ strongly activated SOD1 (up 200% activity), Ca2+ và Zn2+ could increase approximately 20% activity while Cu2+ inhibited more than 60% ativity of the enzyme.

SiO2-coated Fe3O4 nanoparticles (Fe3O4@SiO2 NPs) were successfully synthesized using ultrasound in order to extract DNA from cancer tissues for application in diagnostics. The core 10.7-nm-diameter Fe3O4 nanoparticles were synthesized by co-precipitation of Fe3+ and Fe2+ as reaction substrates and NH4OH as precipitant, then coated with a thin layer of amorphous silica by a modified Stober method. Further SiO2 coating using alkaline hydrolysis of tetraethyl orthosilicate in ethanol and water mixture was accelerated in the presence of a 37-kHz ultrasound, resulting in the NPs having different sizes of 14.5 nm (version M1), 24.4 nm (version M2), and 34.9 nm (version M3) with saturation magnetization values of 50.2 emu/g, 18.6 emu/g, 10.3 emu/g, respectively. Among the three Fe3O4@SiO2 NPs versions, the M1 NPs allowed extraction of DNAs from 10 mg formalin-fixed and paraffin-embedded (FFPE) tissues of nasopharyngeal carcinoma patients with the highest recovery of about 100–500 ng/μl and good purity (A260/A280: 1.8–1.9). The extracted DNAs could be used as templates for downstream amplification of 252-bp sequencing specifically for the Braf cancer biomarker gene using polymerase chain reaction (PCR), as well as detection of the pathogenic Epstein–Barr virus (EBV) and the human papilloma-virus (HPV) using real-time PCR. DNA extraction recoveries of both EBV and HPV using Fe3O4@SiO2 NPs M1 were significantly better that those using commercialized Fe3O4@SiO2 microbeads, as indicated by lower threshold cycles of all fluorescent signals including fluorescein amidite (FAM) dye representative for EBV infection, hexachlorofluorescein (HEX) dye representative for β-globin (internal control), and SYBR Green dye representative for HPV infection in tested clinical samples from patients with nasopharyngeal carcinoma (NPC).

Gold nanoparticles (GNPs) have been synthesized by a chemical reduction method using sodium borohydride and functionalized with amino groups on their surface. The GNPs were then conjugated with the anti-HER2 human antibody (trastuzumab) for detecting breast cancer cells. The specific binding of trastuzumab-conjugated GNPs onto the breast cancer cells (KPL4 line) were observed by bright-field and dark-field microscopy and were for the first time observed by scanning electron microscopy and energy dispersive X-ray scanning. [DOI: 10.1380/ejssnt.2011.544]

Magnetic nanoparticles with a diameter of 15 nm prepared by using the coprecipitation method have been applied to enforce the sedimentation of the solid waste, to adsorb the arsenic ions in water, to increase the DNA concentration by using a magnetic field for the electrochemical DNA sensor and to separate the helper CD4+ T cells to determine the number of the cells in blood. A combination of magnetic nanoparticles and alum makes the solid waste in water under a magnetic field aggregate a dozen times faster than under the gravity alone. A concentration of 0.1 mg/l of arsenic in water was reduced to a value lower than the permissible concentration of 0.01 mg/l after few minutes of stirring. The particles functionalized with 3-aminopropyl triethoxysilane were used to enrich the DNA of the Herpes virus, which extended the sensitivity of an electrochemical sensor down to a concentration lower than nM/l. The particles coated with fluorescent-labeled antiCD4 antibody were used to count the helper CD4+ T cells. The fluorescence signals of the particle/cell system were two times stronger than those of the fluorescence antiCD4 cell system. This can be used for the treatment of an HIV-infected patient with a simple fluorescent microscope. Author

Vemurafenib has recently been used as drug for treatment of melanomas with BRAFV600E mutation. Unfortunately, treatment with only vemurafenib has not been sufficiently effective, with recurrence after a short period. In this study, three vemurafenib-resistant BRAFV600E melanoma cell lines, A375PR, A375MR and SKMEL-28R, were established from the original A375P, A375M and SKMEL-28 cell lines. Examination of the molecular mechanisms showed that the phosphorylation levels of MEK and ERK, which play key roles in the RAS/RAF/MEK/ERK signaling pathway, were reduced in these three cell lines, with increased phosphorylation levels of pAKTs limited to SKMEL-28R cells. Treatment of SKMEL-28R cells with 100 nM paclitaxel resulted in increased apoptosis and decreased cellular proliferation, invasion and colony formation via reduction of expression levels of EGFR and pAKTs. Moreover, vemurafenib-induced pAKTs in SKMEL-28R were decreased by treatment with an AKT inhibitor, MK-2206. Taken together, our results revealed that resistance mechanisms of BRAFV600E-mutation melanoma cells to vemurafenib depended on the cell type. Our results suggested that paclitaxel should be considered as a drug in combination with vemurafenib to treat melanoma cells.

Magnetic Fe3O4nanoparticles were prepared by coprecipitation and then coated with silica. These Fe3O4/SiO2nanoparticles consisted of a 10–15 nm magnetic core and a silica shell of 2–5 nm thickness. The superparamagnetic property of the Fe3O4/SiO2particles with the magnetization of 42.5 emu/g was confirmed by vibrating sample magnetometer (VSM). We further optimized buffers with these Fe3O4/SiO2nanoparticles to isolate genomic DNA of hepatitis virus type B (HBV) and of Epstein-Barr virus (EBV) for detection of the viruses based on polymerase chain reaction (PCR) amplification of a 434 bp fragment ofSgene specific for HBV and 250 bp fragment of nuclear antigen encoding gene specific for EBV. The purification efficiency of DNA of both HBV and EBV using obtained Fe3O4/SiO2nanoparticles was superior to that obtained with commercialized Fe3O4/SiO2microparticles, as indicated by (i) brighter PCR-amplified bands for both HBV and EBV and (ii) higher sensitivity in PCR-based detection of EBV load (copies/mL). The time required for DNA isolation using Fe3O4/SiO2nanoparticles was significantly reduced as the particles were attracted to magnets more quickly (15–20 s) than the commercialized microparticles (2-3 min).

Proline (Pro) and Trehalose (Tre) function as compatible solutes and are upregulated in plants under abiotic stress. They play an osmoprotective role in physiological responses, enabling the plants to better tolerate the adverse effects of abiotic stress. We investigated the effect of exogenous Pro and Tre (10 mM) in seedlings of Thai aromatic rice (cv. KDML105; salt-sensitive) during salt stress and subsequent recovery. Salt stress (S, NaCl) resulted in growth reduction, increase in the Na(+)/K(+) ratio, increase in Pro level and up-regulation of Pro synthesis genes (pyrroline-5-carboxylatesynthetase, P5CS; pyrroline-5-carboxylate reductase, P5CR) as well as accumulation of hydrogen peroxide (H(2)O(2)), increased activity of antioxidative enzymes (superoxide dismutase, SOD; peroxidase, POX; ascorbate peroxidase, APX; catalase, CAT) and transcript up-regulation of genes encoding antioxidant enzymes (Cu/ZnSOD, MnSOD, CytAPX, CatC). Under salt stress, exogenous Pro (PS; Pro+NaCl) reduced the Na(+)/K(+) ratio, further increased endogenous Pro and transcript levels of P5CS and P5CR, but decreased the activity of the four antioxidant enzymes. The transcription of genes encoding several antioxidant enzymes was upregulated. Exogenous Tre (TS; Tre+NaCl) also reduced the Na(+)/K(+) ratio and strongly decreased endogenous Pro. Transcription of P5CS and P5CR was upregulated, the activities of SOD and POX decreased, the activity of APX increased and the transcription of all antioxidant enzyme genes upregulated. Although exogenous osmoprotectants did not alleviate growth inhibition during salt stress, they exhibited a pronounced beneficial effect during recovery period showing higher percentage of growth recovery in PS (162.38%) and TS (98.43%) compared with S (3.68%). During recovery, plants treated with PS showed a much greater reduction in endogenous Pro than NaCl-treated (S) or Tre-treated plants (TS). Increase in CAT activity was most related to significant reduction in H(2)O(2), particularly in the case of PS-treated plants. Advantageous effects of Pro were also associated with increase in APX activity during recovery.

Background Wound healing has being extensively investigated over the world. Healing impairment is caused by many reasons including increasing of free-radicals-mediated damage, delaying in granulation tissue formation, reducing in angiogenesis and decreasing in collagen reorganization. These facts consequently lead to chronic wound healing. Piper betle Linn (Betle) leaves have been folklore used as an ingredient of drugs for cutaneous wound treatment. However, the effect of betle leaf on wound healing is not yet well elucidated. In this study, we aimed to investigate the healing efficacy of methanol leaf extract of Piper betle Linn on proliferation of fibroblast NIH3T3 cells as well as full-thickness burn and excision wounds in swiss mice. Methods Scratch wound healing assays were conducted to examine the effects of betle leaf extract on healing activity of fibroblast cells. Burn and excision wounds on swiss mouse skins were created for investigating the wound healing progress caused by the betle leaf extract. Malondialdehyde (MDA) was also evaluated to examine the products of lipid hydroperoxide (LPO) under conditions of with or without betle leaf extract treatment. Results The results of this study showed that Piper betle Linn leaf extract in methanol increased proliferation of NIH3T3 cells and promoted wound healing in vitro and in vivo with both burn wound and excision wound models. In addition, this extract significant decreased level of malondialdehyde (MDA) in liver of treated-mice compared with that in non-treated mice. Conclusions Our results suggest that Piper betle Linn can be used as an ingredient in developing natural origin drugs for treatment of cutaneous wounds.