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791.
792.
New records of the Japanese seahorse Hippocampus mohnikei in Southeast Asia lead to updates in range,habitat and threats
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L. Aylesworth J. M. Lawson P. Laksanawimol P. Ferber T.‐L. Loh 《Journal of fish biology》2016,88(4):1620-1630
New records of the Japanese seahorse Hippocampus mohnikei from Cambodia, Malaysia, Thailand and Vietnam, along with recently published studies from India and Singapore, have greatly expanded the known range of H. mohnikei within Southeast Asia. These new records reveal novel habitat preferences and threats to H. mohnikei in the region. Although the global conservation status of H. mohnikei is classified as Data Deficient according to the IUCN Red List of Threatened Species, new sightings indicate that this species is found in similar habitats and faces similar threats as other Hippocampus species that are considered Vulnerable. 相似文献
793.
Differential expression of asialo GM1 on alloreactive cytotoxic T lymphocytes and lymphokine-activated killer cells 总被引:2,自引:0,他引:2
The present study was undertaken to examine the differential expression of asialo GM1 (AsGM1) on the responding cells and effectors of alloreactive cytotoxic T lymphocytes (CTL) and lymphokine-induced activated killers (LAK). It was found that AsGM1 was expressed on the 3-day-cultured LAK effectors. Its expression gradually disappeared to the extent that AsGM1 became undetectable after 5 to 6 days of culturing. In contrast, AsGM1 was detected on 3-day CTL generated in mixed-lymphocyte cultures (bulk cultures); however, the levels of AsGM1 expression remained the same for at least 7 days. When examining the expression of AsGM1 on the responding cells, the reciprocal results were obtained. AsGM1 was expressed the LAK responders, but we were unable to demonstrate AsGM1 on CTL responders. Depletion of AsGM1+ cells from the responding population reduced subsequent CTL responses; however, CTL responses could be restored by adding conditioned media containing both interleukin 2 (IL-2) and other helper-T-cell factors and could not be restored by purified IL-2 alone adding at comparable doses. Reconstituting the AsGM1-depleted responders with Lyt-2-depleted splenocytes also restored the CTL response. Furthermore, depletion of AsGM1 cells from the responding population did not reduce the precursor frequency of allo-CTL, whereas the precursor frequency of LAK cells was reduced 42-fold. These findings show that the reduction of CTL responses after depletion of AsGM1+ cells was not due to the removal of precursors; instead, the defect appeared to be in the helper population. We further found that the helper defect was not due to impaired IL-2 production, because the endogenous production of IL-2 AsGM1-depleted responders was not reduced. Therefore, AsGM1+ cells may play a role in the helper pathway other than IL-2 production. 相似文献
794.
Complex coacervation of alginate-chitosan and alginate-gelatin were used to develop two-coat systems for the encapsulation of Spathoglottis plicata seeds and protocorms (top-shaped structures formed after seed germination of orchids). Both the seeds and the protocorms could withstand the encapsulation treatments with high viability. About 54% of seeds and 40% of large protocorms (1.6-2.0 mm) were able to tolerate a 6-h desiccation treatment. However, viability of the small protocorms (0.7-0.9 mm) was greatly reduced if they were desiccated before encapsulation. Encapsulation after desiccation significantly increased the percentage viability of seeds and protocorms. Treatment with abscisic acid (ABA, 10(-5) M) before desiccation and encapsulation resulted in high percentage viability in seeds and large protocorms whereas the small protocorms were found to be less tolerant to the treatments. Copyright 1998 John Wiley & Sons, Inc. 相似文献
795.
A truncated version of the white spot syndrome virus (WSSV) 27.5 kDa envelope protein was expressed as a histidine tag fusion protein in Escherichia coli. The bacterial expression system allowed the production of up to 10 mg of purified recombinant protein per liter of bacterial culture. Antiserum from a rabbit immunized with the recombinant protein recognized the 27.5 kDa viral envelope protein of WSSV isolated from different geographic regions. The antiserum did not recognize any of the other known WSSV structural proteins. A sensitive immunodot assay for WSSV was developed using the specific rabbit polyclonal antiserum. 相似文献
796.
Oligonucleotides directed towards the active site regions of aspartic proteases were used as primers for the polymerase chain reaction to identify a unique sequence (asppcr1) from the AtT-20 anterior pituitary corticotrope cell line. Asppcr1 showed the greatest similarity (85% identity) to human cathepsin E [(1989) J. Biol. Chem. 264, 16748-16753]. Northern blot analysis of AtT-20 RNA revealed a single 1.9 kB message. Nuclease protection experiments indicated that asppcr1 mRNA was present in pancreas, spleen, testis and liver at low levels and undetectable in heart and brain. This contrasted with the lysosomal aspartic protease, cathepsin D whose mRNA showed a broader tissue distribution. The restricted message distribution of asppcr1 supports a more specific role for this aspartic protease in aspect(s) of cellular physiology. 相似文献
797.
Kevin?J. Galinsky Gaurav Bhatia Po-Ru Loh Stoyan Georgiev Sayan Mukherjee Nick?J. Patterson Alkes?L. Price 《American journal of human genetics》2016,98(3):456-472
Searching for genetic variants with unusual differentiation between subpopulations is an established approach for identifying signals of natural selection. However, existing methods generally require discrete subpopulations. We introduce a method that infers selection using principal components (PCs) by identifying variants whose differentiation along top PCs is significantly greater than the null distribution of genetic drift. To enable the application of this method to large datasets, we developed the FastPCA software, which employs recent advances in random matrix theory to accurately approximate top PCs while reducing time and memory cost from quadratic to linear in the number of individuals, a computational improvement of many orders of magnitude. We apply FastPCA to a cohort of 54,734 European Americans, identifying 5 distinct subpopulations spanning the top 4 PCs. Using the PC-based test for natural selection, we replicate previously known selected loci and identify three new genome-wide significant signals of selection, including selection in Europeans at ADH1B. The coding variant rs1229984∗T has previously been associated to a decreased risk of alcoholism and shown to be under selection in East Asians; we show that it is a rare example of independent evolution on two continents. We also detect selection signals at IGFBP3 and IGH, which have also previously been associated to human disease. 相似文献
798.
The question of whether tumors are warmer or colder than surrounding tissue is considered in these experiments which use a highly suitable animal model, the hairless mouse. Temperatures of skin over induced growing subdermal tumors in these mice were monitored by AGA 680 Color Thermovision. The skin over the tumors does not cool over time but on the contrary becomes warmer. This is probably due to an increase in vascularization rather than increased metabolic rate. 相似文献
799.
800.
The Na+ and energy dependent uptake of norepinephrine into cortical rat brain homogenates or purified nerve ending particles (NEP) is reduced by prior trypsin treatment. In contrast, the uptake of dopamine, serotonin, choline and γ-aminobutyric acid is markedly less sensitive to the effect of trypsin. Kinetic analyses indicate that the trypsin-induced decrease of norepinephrine uptake is non-competitive. In the dose range studied, trypsin did not appreciably alter the protein content or morphology of NEP. However, in a dose related fashion, trypsin decreased the glycoprotein content of NEP measured as the loss of protein bound N-acetylneuraminic acid. 相似文献