In-situ growth of ZnO particles on bamboo pulp fabric and its anti-UV property

This research presents a simple way to enhance the anti-UV property of bamboo pulp fabric trough in situ synthesis of ZnO particles on the fabric. Bamboo Pulp Fabric was treated by immersion method in Zn(NO₃)₂ and multi-amide compound (RSD) aqueous solution under hydrothermal condition, then the ZnO particles were grown on the surface of bamboo pulp fabric by in-situ method. In this synthesis RSD was applied as a stabilizer, reactant and dispersant agent, the reaction mechanism was investigated. The ZnO particles were characterized by transmission electron microscope (TEM), Xray diffraction (XRD) and ultraviolet/visible light spectrophotometer. The anti-UV property of Bamboo Pulp Fabric was characterized by measuring its UPF. The results indicated that the diameter of ZnO is about 150 nm, the length is about 600 nm. The Bamboo Pulp Fabric treated with ZnO particles showed good anti-UV property and its UPF can reach to 83.59. After washing for 20 times, it can also keep good anti-UV property.     

The effect of water temperature on habitat use of young Pacific bluefin tuna Thunnus orientalis in the East China Sea

ABSTRACT:   Immature Pacific bluefin tuna Thunnus orientalis , tagged with archival tags, were released near Tsushima Island in the East China Sea (ECS) during the winters of 1995, 1996 and 1997. Geolocations were estimated using the archival tags from recovered fish. These data, together with sea surface temperature (SST) data from satellite remote sensing, are used to describe the habitat used by these bluefin in the ECS from January to June for 3 years (1996, 1997, 1998), and to asses the effect of water temperature on fish distribution and movement. The results indicate that their geolocations ranged from the area north-east of Tsushima Island to the offshore area in the south-west. However, the area of highest density differed among years, being furthest south in 1996 and furthest north in 1998. The differences were probably caused by changes in SST associated with La Niña (1996) and El Niño (1998) events. Another densely populated area was identified in offshore waters of latitude 28–30 °N in 1996 (only), on the cold side of the Kuroshio front. These fish may have been prevented from moving northwards by an intrusion of Kuroshio water of approximately 25°C into the region immediately to the north-east.     

Drug resistance of bacteria isolated from the intestine of yellowtail cultured with feeds containing various drugs

ABSTRACT: In order to ascertain whether the use of drugs as feed additive for fish may cause drug resistance of bacteria in the intestinal tract, viable counts and bacterial flora in the intestine of yellowtail cultivated with the feeds in the presence or absence of various drugs, drug resistance of the flora were determined. Viable counts in the intestine were lowered remarkably by the administration of each drug, suggesting that bacterial growth in the intestinal tract was inhibited by various drugs. Bacterial flora in the intestine consisted mainly of coryneform bacteria, Staphylococcus and Bacillus regardless of whether drugs were administered or not. In these floras, significant differences could not be observed for their resistance to respective drugs among the isolates from fish cultivated with feeds containing or not containing each drug. In addition, these floras mainly showed resistance to various combinations comprising from one to seven drugs; moreover, the majority of resistant strains were multidrug-resistant.     

Cdk2 activity is essential for the first to second meiosis transition in porcine oocytes

The meiotic progression of Xenopus oocytes has been suggested to depend on the activity of cyclin-dependent kinase 2 (Cdk2). We examined whether Cdk2 is involved in the regulation of mammalian oocyte meiosis by injecting porcine oocytes with anti-Cdk2 antibody. At first, the cross-reactivity of the anti-Cdk2 antibody with Cdc2 kinase was evaluated by immunoprecipitation and immunoblotting experiments using porcine granulosa cell extract, and no cross-reactivity with Cdc2 kinase was observed in the antibody used. In the anti-Cdk2 antibody-injected group, 50.7% of the oocytes were arrested in the second metaphase after 50 h of culture and this rate was significantly lower than those in the non-injected intact oocytes or the oocytes injected with mouse IgG (84.5% and 86.7%, respectively). Most of the other oocytes in the antibody-injected group formed a pronucleus without polar bodies or with only one polar body. The cyclin B1 amount in the antibody-injected and activated oocytes was dramatically decreased compared with that in the intact or mouse IgG-injected oocytes after 50 h of culture. These results suggest that Cdk2 is involved in the meiotic maturation of mammalian oocytes, and that the block of Cdk2 activity results in the failure of cyclin B1 accumulation and second meiosis induction.     

Whey acidic protein (WAP) depresses the proliferation of mouse (MMT) and human (MCF-7) mammary tumor cells

We previously reported that the enforced expression of exogenous whey acidic protein (WAP) significantly inhibited the proliferation of mouse mammary epithelial cells (HC11 and EpH4/H6 cells). This paper presents the first evidence that WAP also depresses the proliferation of mammary tumor cells from mouse (MMT cells) and human (MCF-7 cells). We established WAP-clonal MMT and MCF-7 cell lines, and confirmed the secretion of WAP from the WAP-clonal cells into culture medium. The enforced expression of WAP significantly inhibited the proliferation of MMT and MCF-7 cells in in vitro culture. FACScan analyses revealed that G0/G1 phase cell-cycle progression was disordered and elongated in the WAP-clonal MMT and MCF-7 cells compared to that of the control cells. The expression of cyclin D1 was significantly decreased in the WAP-clonal MMT and MCF-7 cells, suggesting that progression from the G1 to the S phase was delayed in the WAP-clonal cells. The present results indicate that WAP plays a negative regulatory role in the cell-cycle progression of mammary tumor cells via a paracrine mechanism.     

Dicalcium phosphate reaction with soils during 2N ammonium sulfate extraction

The consistent method for fractionation of soil phosphorus has already been recommended by M.L. Jackson et al. (1,2,3) based on the solubility product of different soil phosphates, and being widely applied for soil research and practice. Lately, some criticism of the method arose as to the probability of dissolution in 0.5 M ammonium fluoride solution of freshly formed dicalcium phosphate and other reaction products of fertilizer recently added to soil. Since dicalcium phosphate is of nature soluble in ammonium fluoride, as well as aluminium phosphate, if dicalcium phosphate was contained in appreciable amount in soil, so that the value of aluminum phosphate to be dissolved into ammonium fluoride must become higher beyond the real value. It is, therefore, significant to know the fate of applied phosphate fertilizer and the status of native labile phosphate.     

Effect of group culture and embryo-culture conditioned medium on development of bovine embryos

We investigated the effect of group culture on bovine embryo development, and also investigated the effect of embryo-culture conditioned medium on developmental competence of individually cultured bovine embryos. Slaughterhouse-derived bovine oocytes were matured and fertilized in vitro. The presumptive zygotes were cultured individually or cultured in groups of 2 to 5 embryos with a constant culture density (5 mul/embryo). After 7 days of culture, the rates of embryos developed to the blastocyst stage were significantly higher (P < 0.05) in group cultures of more than 3 embryos/drop than for embryo culture of 1 or 2 embryos/drop. These results suggest a beneficial effect of group culture may be exerted by possible growth promoting factors secreted by embryos. In the next experiment, we investigated the effect of timing of fresh medium replacement on the development of embryos cultured in groups. The blastocyst formation rate was lower when culture medium was replaced freshly on days 2-4 after fertilization than on days 5-6. The blastocyst formation rates of single-cultured embryos were significantly (p < 0.05) increased by the addition of conditioned medium derived from multiple-embryo culture. These results indicate that group culture promotes embryo development and that embryo culture-derived conditioned medium is effective for supporting development of single cultured embryos.     

Analysis of the promoter of mutated human whey acidic protein (WAP) gene

Although whey acidic protein (WAP) has been identified in the milk of a range of species, it has been predicted that WAP is not secreted into human milk as a result of critical point mutations within the coding region. In the present study, we first investigated computationally the promoter region of mutated human WAP genes by comparing with those of other known WAP genes. Computational database analyses showed that the human WAP promoter region was highly conserved, as in other species with milk WAP. Next, we evaluated the activity of the human WAP promoter (2.6 kb) using a reporter gene assay. MCF-7 cells were stably transfected with the hWAP/hGH (human growth hormone) fusion gene, cultured on Matrigel, and treated with lactogenic hormones. Radioimmunoassay detected hGH in the culture medium, indicating that the human WAP promoter was responsible for the lactogenic hormones. The human WAP promoter was significantly more active in MCF-7 cells than the mouse WAP promoter (2.4 kb). The present results provide us with important information on the molecular evolution of milk protein genes.     

A simple and efficient method for extraction of PCR-amplifiable DNA from chicken eggshells

Recently, we reported a method for discriminating a Japanese brand of chicken, the Hinai-jidori. As an application of this method for discriminating Hinai-jidori eggs, we here report an efficient method for extracting maternal DNA from eggshells. Eggshell powder was completely decalcified with EDTA solution, and then DNA was isolated by conventional phenol-chloroform extraction and ethanol precipitation. The efficiency of DNA recovery from eggshells was 50-fold higher than that of a previously reported method. The recovered DNA could be used for PCR, and 10 markers for identifying the Hinai-jidori chicken were detected. The genotypes of the Hinai-jidori exactly matched those of the Hinai-dori breed. Using this method, Hinai-jidori and Hinai-dori eggs could be distinguished from the eggs of Rhode Island Reds. This is the first report of a technique that can be used to discriminate the eggs of Hinai-jidori from those of other chickens, and it can also be utilized to validate the labeling of Hinai-jidori eggs in the market.     

Use of fluorescent proteins to visualize interactions between the Bakanae disease pathogen <Emphasis Type="Italic">Gibberella fujikuroi</Emphasis> and the biocontrol agent <Emphasis Type="Italic">Talaromyces</Emphasis> sp. KNB-422

Talaromyces sp. isolate KNB-422, isolated from a rice seedling, is a biofungicidal agent effective against several seedborne pathogens of rice including Gibberella fujikuroi, which causes Bakanae disease. Because the fungal mode of action (MOA) has not yet been clarified, we used the fluorescent protein markers GFP and RFP to visualize cell–cell interactions between the biocontrol agent and the pathogen G. fujikuroi. In slide culture, the hyphal cell wall of G. fujikuroi collapsed, and fluorescence of its cytoplasm disappeared 3 days after contact with hyphae of Talaromyces sp. On inoculated rice plants, both fungi occupied the same regions of coleoptiles and roots, where the biocontrol effect of Talaromyces sp. must be exerted. Our observations suggest that the MOA of Talaromyces sp. is mycoparasitic.