Hepatocyte Growth Factor (HGF)-Induced Cell Migration Is Negatively Modulated by Epidermal Growth Factor through Tyrosine Phosphorylation of the HGF Receptor

Hepatocyte growth factor (HGF) stimulated cell migration of human gastric carcinoma cell lines MKN1, MKN7, and MKN28. Epidermal growth factor (EGF) also stimulated the cell migration of these three cell lines. In MKN7 cells, HGF-stimulated cell migration was rather reduced in the presence of EGF, whereas such an observation was not made with MKN1 and MKN28 cells. Therefore, we compared the effect of EGF on HGF-stimulated HGF receptor phosphorylation in these cell lines. HGF induced a rapid tyrosine phosphorylation of the HGF receptor in all these cell lines. In MKN7 cells, the increased phosphorylation was further enhanced by EGF, although EGF alone did not affect tyrosine phosphorylation of the HGF receptor. In MKN1 and MKN28 cells, EGF did not influence tyrosine phosphorylation of the HGF receptor, whether HGF was present or not. The data presented here suggest that EGF negatively modulates the cellular response to HGF by increasing tyrosine phosphorylation of the HGF receptor in certain types of epithelial cells, e.g., MKN7 cells.     

Controlled release of adeno-associated virus from alginate hydrogel microbeads with enhanced sensitivity to ultrasound

Adeno-associated virus (AAV)-based gene therapy holds promise as a fundamental treatment for genetic disorders. For clinical applications, it is necessary to control AAV release timing to avoid an immune response to AAV. Here we propose an ultrasound (US)-triggered on-demand AAV release system using alginate hydrogel microbeads (AHMs) with a release enhancer. By using a centrifuge-based microdroplet shooting device, the AHMs encapsulating AAV with tungsten microparticles (W-MPs) are fabricated. Since W-MPs work as release enhancers, the AHMs have high sensitivity to the US with localized variation in acoustic impedance for improving the release of AAV. Furthermore, AHMs were coated with poly-l -lysine (PLL) to adjust the release of AAV. By applying US to the AAV encapsulating AHMs with W-MPs, the AAV was released on demand, and gene transfection to cells by AAV was confirmed without loss of AAV activity. This proposed US-triggered AAV release system expands methodological possibilities in gene therapy.     

Solubilization of human placental tumor necrosis factor receptors as a complex with a guanine nucleotide-binding protein.

Human placental membranes exhibited high-affinity receptors for tumor necrosis factor (TNF) (Kd = 5.6 x 10(-10) M) with a density of 1.2-1.7 x 10(10) sites/mg protein. The receptors were solubilized from these membranes with 1% Nonidet P-40, and the solubilized receptor was adsorbed to Con A-Sepharose and wheat germ agglutinin agarose columns, indicating that the TNF receptor derived from human placenta contains carbohydrate chains recognized by these lectins. TNF binding activity was eluted from a column of Sephacryl S-300 as a single peak of Mr 300 kDa. The solubilized receptor was further purified by TNF-Sepharose prepared by coupling of TNF to tresyl-activated Sepharose 4B. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis analysis of the purified sample resolved five major bands of Mr 90, 78, 41, 35, and 11 kDa, suggesting that these polypeptides constitute a multimeric complex with a molecular mass of 300 kDa, as observed in gel filtration study. Furthermore, the TNF-Sepharose-bound fraction demonstrated GTP gamma S binding and GTPase activity. Immunoblot analysis showed that the 41- and 35-kDa polypeptides were recognized by antisera against alpha subunits and beta subunit of GTP-binding proteins, respectively. These results suggest that the native TNF receptor couples to a guanine nucleotide-binding protein to form a large complex structure in human placental membranes.     

Lagrangian tracking measurements revealed the temporal dynamics of nitrogen and phosphorus spiralling in a large Japanese river

Limnology - The in-stream processing of nutrients plays an important role in the fluvial nutrient transport from lands to the ocean, but few empirical studies have addressed the temporal dynamics...     

The impact of land use and climate change on surface runoff and groundwater in Cimanuk watershed,Indonesia

Limnology - The Cimanuk River with a total watershed area of 4010.8 km2 flowing from the Garut Regency to Indramayu Delta is the longest in West Java Province. However, the cumulative...     

Export of dissolved iron from river catchments in northeast Japan

Landscape and Ecological Engineering - This study investigated the export of dissolved iron (DFe) from river catchments with emphasis on land use and land cover (LULC). The DFe concentrations were...     

Cleome hassleriana plants fully support the development and reproduction of Nesidiocoris tenuis

BioControl - Nesidiocoris tenuis (Reuter) (Hemiptera: Miridae) is a zoophytophagous predator that feeds on plants as well as prey. Several non-crop host plant species have been used to maintain...     

Rapid and accurate quantitative analysis of fermentation gases by Raman spectroscopy

Raman spectroscopy was employed for the precise quantitative analysis of a gaseous mixture. The band ratio between the Raman band of the target gas and that of the external standard was calculated and found to be proportional to the pressure of the target gas. The linearity of the calibration curves was very good (higher than 0.999). The mole fractions of atmospheric nitrogen and atmospheric oxygen were determined from their partial pressures. The average molar fraction of atmospheric nitrogen was calculated to be 0.790, similar to the literature value. Those of methane, hydrogen, and carbon dioxide, which are produced by fermentation, were also determined from the Raman spectrum. The values were identical to those obtained from the measured volume of each gas. The possibility of quantifying gas molecules by Raman spectroscopy is demonstrated.     

Anesthetic Effects of a Mixture of Medetomidine,Midazolam and Butorphanol in Two Strains of Mice

The combination of ketamine and xylazine is a widely used anesthetic for laboratory animals. However, due to an abuse problem in Japan, ketamine has been specified as a narcotic since 2007. Instead of using ketamine, Kawai et al. reported an injectable formula with an equivalent effect to the mixture of ketamine and xylazine [11]. The mixture of 0.3 mg/kg body weight (b.w.) medetomidine (Med.), 4.0 mg/kg b.w. midazoram (Mid.), and 5.0 mg/kg b.w. butorphanol (But.) produced an anesthetic duration of around 40 min in outbred ICR mice. However, the anesthetic effect of the mixture for inbred mice strains remains unknown. Therefore, we examined anesthetic effects of the mixture of Med., Mid., and But. in the BALB/c and C57BL/6J strains. After intraperitoneal injection into mice, right front paw, left hind paw, and tail pinch reflexes as well as corneal and righting reflexes were observed. Every 5 min, we scored each reflex category as 0 for reaction or 1 for no reaction. As long as the total score was at least 4 out of 5, we considered the mixture as putting a mouse in a surgical anesthetic state. The mixture produced an anesthetic duration of more than 45 min in both strains of mice. These results indicate that the mixture of Med., Mid., and But. can be a useful and effective anesthesia for the BALB/c and C57BL/6J strains of inbred mice as well as outbred ICR mice.