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1.
Shallow-water vegetated estuarine habitats, notably seagrass, mangrove and saltmarsh, are known to be important habitats for
many species of small or juvenile fish in temperate Australia. However, the movement of fish between these habitats is poorly
understood, and yet critical to the management of the estuarine fisheries resource. We installed a series of buoyant pop nets
in adjacent stands of seagrass, mangrove and saltmarsh in order to determine how relative abundance of fishes varied through
lunar cycles. Nets were released in all habitats at the peak of the monthly spring tide for 12 months, and in the seagrass
habitat at the peak of the neap tide also. The assemblage of fish in each habitat differed during the spring tides. The seagrass
assemblage differed between spring and neap tide, with the neap tide assemblage showing greater abundances of fish, particularly
those species which visited the adjacent habitats when inundated during spring tides. The result supports the hypothesis that
fish move from the seagrass to the adjacent mangrove and saltmarsh during spring tides, taking advantage of high abundances
of zooplankton, and use seagrass as a refuge during lower tides. The restoration and preservation of mangrove and saltmarsh
utility as fish habitat may in some situations be linked to the proximity of available seagrass. 相似文献
2.
Amitabha Mazumder Elizabeth A. Grimm Steven A. Rosenberg 《Cancer immunology, immunotherapy : CII》1998,15(1):1-10
Summary We have previously demonstrated that cancer patients' peripheral blood lymphocytes (PBL) allosensitized against single or pool normal donor PBL are capable of lysing fresh autologous tumor cells in a 4-h 51Cr-release assay. In this report, we present further investigations into this phenomenon. These alloactivated killer cells (A-AK cells) lysed autologous and allogeneic tumors and allogeneic but not autologous PBL. Furthermore, cold target inhibition studies demonstrated that autologous and allogeneic tumors were lysed by the same effector cells. Multiple metastases from the same patient were equivalently lysed by these A-AK cells. The presence of adherent cells and proliferation of the precursors were necessary to generate A-AK cells, although the effector cell itself was radioresistant and nonadherent. The effects of allosensitization were enhanced by the addition of lectin-free interleukin-2 preparations to the in vitro culture by partial depletion of adherent cells prior to sensitization. The A-AK effector cell was OKT3+, OKT8+, OKT4–, OKM1– and could be generated by just 3 days of allosensitization. The precursors for A-AK cells could be separated from NK cells on percoll gradients and lysis could be generated from thoracic duct lymphocytes, a population devoid of NK cells. The phenotype of the majority of the precursor cells was OKT3+, OKT4–. These allocatived PBL could be expanded in crude or lectin-free interleukin-2 without loss of cytotoxicity for fresh autologous tumor cells. Activated T cells represent a population of non-NK cells with broad lytic specificity for fresh tumor cells. Such cells may be of value in the adoptive immunotherapy of human solid tumors and may play a role in immune surveillance. 相似文献
3.
Summary A preliminary study of formate production from CO plus H2O using the intact cells ofMethanosarcina barkeri was conducted. Formate production from CO gas required the participation of three enzymes, CO dehydrogenase, hydrogenase and formate dehydrogenase. Hypophosphite inhibited formate formation from CO plus H2O by about 80%. In this system, 9 g/l of formate could be obtained from CO gas after 48 h of incubation at 37°C, pH 8.0. 相似文献
4.
A solid‐state fermentation (SSF) system for production of an industrially important enzyme laccase by Pleurotus ostreatus was developed by using potato dextrose yeast extract medium and polyurethane foam as a supporting material. The maximum laccase production in the SSF system was as high as 3×105 U/L. Addition of inducers, such as copper and ferulic acid, further enhanced the laccase production in SSF. Moreover, the time required for the maximum laccase production was reduced to 6 days compared to 10 days reported earlier. The improvement achieved by the SSF system was investigated by comparing it to a submerged fermentation system (SmF), both experimentally and by using a standard theoretical model along with a parameter sensitivity analysis. Laccase production in SSF was found to be twice of that in SmF. One of the main reasons for higher laccase production in SSF compared to SmF was possibly due to the presence of higher proteolytic activity in SmF. Strong proteolytic activity in SmF presumably caused subsequent laccase degradation, which lowered the ultimate laccase production in SmF compared to SSF. 相似文献
5.
Vipin Kumar Sharma Khomendra Kumar Sarwa Bhaskar Mazumder 《Journal of liposome research》2014,24(2):83-89
Liposomes are well known lipid carriers for drug delivery of bioactive molecules encapsulated inside their membrane. Liposomes as skin drug delivery systems were initially promoted primarily for localized effects with minimal systemic delivery. Subsequently, a novel vesicular system, transferosomes was reported for transdermal delivery with efficiency similar to subcutaneous injection. The multiple bilayered organizations of lipids applied in these vesicles structure are somewhat similar to complex nature of stratum corneal intercellular lipids domains. The incorporation of novel agents into these lipid vesicles results in the loss of entrapped markers but it is similar to fluidization of stratum corneum lipids on treatment with a penetration enhancer. This approach generated the utility of penetration enhancers/fluidizing agents in lipids vesicular systems for skin delivery. For the transdermal and topical applications of liposomes, fluidity of bilayer lipid membrane is rate limiting which governs the permeation. This article critically reviews the relevance of using different types of vesicles as a model for skin in permeation enhancement studies. This study has also been designed to encompass all enhancement measurements and analytical tools for characterization of permeability in liposomal vesicular system. 相似文献
6.
A Mazumder C B Chen R Gaynor D S Sigman 《Biochemical and biophysical research communications》1992,187(3):1503-1509
The 1,10-phenanthroline-cuprous complex (OP-Cu) with hydrogen peroxide as a coreactant nicks the single-stranded loops and bulges of RNA stem-loop structures more rapidly than the double-stranded stems. This chemical nuclease is therefore a useful footprinting reagent for these regions and can be used to monitor both intramolecular and intermolecular hybridization of single-stranded domains. The formation of A-form structures characteristic of either RNA-RNA or RNA-DNA duplexes inhibits scission because it blocks the binding site of the coordination complex in single-stranded loops and not because the oxidatively sensitive hydrogens of the ribose moiety are blocked. The C-4' and C-1' hydrogens are accessible to solvent in A-structures. 相似文献
7.
8.
Translational silencing of ceruloplasmin requires the essential elements of mRNA circularization: poly(A) tail, poly(A)-binding protein, and eukaryotic translation initiation factor 4G 总被引:1,自引:0,他引:1 下载免费PDF全文
Mazumder B Seshadri V Imataka H Sonenberg N Fox PL 《Molecular and cellular biology》2001,21(19):6440-6449
9.
Kulkarni AR Peña MJ Avci U Mazumder K Urbanowicz BR Pattathil S Yin Y O'Neill MA Roberts AW Hahn MG Xu Y Darvill AG York WS 《Glycobiology》2012,22(3):439-451
Glucuronoxylans with a backbone of 1,4-linked β-D-xylosyl residues are ubiquitous in the secondary walls of gymnosperms and angiosperms. Xylans have been reported to be present in hornwort cell walls, but their structures have not been determined. In contrast, the presence of xylans in the cell walls of mosses and liverworts remains a subject of debate. Here we present data that unequivocally establishes that the cell walls of leafy tissue and axillary hair cells of the moss Physcomitrella patens contain a glucuronoxylan that is structurally similar to glucuronoxylans in the secondary cell walls of vascular plants. Some of the 1,4-linked β-D-xylopyranosyl residues in the backbone of this glucuronoxylan bear an α-D-glucosyluronic acid (GlcpA) sidechain at O-2. In contrast, the lycopodiophyte Selaginella kraussiana synthesizes a glucuronoxylan substituted with 4-O-Me-α-D-GlcpA sidechains, as do many hardwood species. The monilophyte Equisetum hyemale produces a glucuronoxylan with both 4-O-Me-α-D-GlcpA and α-D-GlcpA sidechains, as does Arabidopsis. The seedless plant glucuronoxylans contain no discernible amounts of the reducing-end sequence that is characteristic of gymnosperm and eudicot xylans. Phylogenetic studies showed that the P. patens genome contains genes with high sequence similarity to Arabidopsis CAZy family GT8, GT43 and GT47 glycosyltransferases that are likely involved in xylan synthesis. We conclude that mosses synthesize glucuronoxylan that is structurally similar to the glucuronoxylans present in the secondary cell walls of lycopodiophytes, monilophytes, and many seed-bearing plants, and that several of the glycosyltransferases required for glucuronoxylan synthesis evolved before the evolution of tracheophytes. 相似文献
10.
Noncancer risk assessment of arsenic safe and unsafe water uses: Bayesian estimation on cohort study
Cancer and noncancer risk of arsenic exposure depends on arsenic intake through drinking water and diets. The present study evaluated the probability of noncancer effects of arsenic exposure from drinking water and diets in a cohort of 82 participants in arsenic-endemic rural areas, considering arsenic-safe and arsenic-unsafe water uses for three consecutive years. The risk assessment included the collection of last 24 hours' diet replica and urine of the participants followed by total arsenic analysis of the same. Toxic dose emerging from exposure duration is a nonlinear variable. So, Bayesian estimation of the data for noncancer risk assessment of the variable arsenic consumption was performed. In spite of using arsenic-safe water, we observed arsenic consumption and release. Participants with skin lesions had more arsenic in urine than participants without skin lesions. Future risk for participants without skin lesions was twice due to less arsenic release in urine. For the first time, Bayesian simulation was used to assess noncancer risk on a cohort for a consecutive three-year study. A significant finding was the higher assessed noncancer risk of the participants without skin lesions than the participants with skin lesions. 相似文献