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991.
Livestock wastewater that is discharged into rivers and ponds results in eutrophication, which would then cause an increase in microorganisms, microalgae, and macrophytes. The derivatives of which critically damage aquatic life and agricultural irrigation. This study designed a swine farm wastewater bioremediation system, by using tubular chained cyanobacteria-immobilized agar–alginate blocks and cyanobacteria biological absorption to reduce wastewater pollution. Swine farm wastewater was filtered through a long tube stuffed with cyanobacteria (Dermocarpella sp.)-immobilized agar–alginate blocks. The removal efficiencies of biological oxygen demand, chemical oxygen demand, phosphorous, ammonia, and suspension solids were evaluated. 相似文献
992.
Rheal A. Towner Nataliya Smith Debra Saunders Patricia Coutinho De Souza Leah Henry Florea Lupu Robert Silasi-Mansat Marilyn Ehrenshaft Ronald P. Mason Sandra E. Gomez-Mejiba Dario C. Ramirez 《生物化学与生物物理学报:疾病的分子基础》2013,1832(12):2153-2161
Free radicals play a major role in gliomas. By combining immuno-spin-trapping (IST) and molecular magnetic resonance imaging (mMRI), in vivo levels of free radicals were detected within mice bearing orthotopic GL261 gliomas. The nitrone spin trap DMPO (5,5-dimethyl pyrroline N-oxide) was administered prior to injection of an anti-DMPO probe (anti-DMPO antibody covalently bound to a bovine serum albumin (BSA)–Gd (gadolinium)-DTPA (diethylene triamine penta acetic acid)–biotin MRI contrast agent) to trap tumor-associated free radicals. mMRI detected the presence of anti-DMPO adducts by either a significant sustained increase (p < 0.001) in MR signal intensity or a significant decrease (p < 0.001) in T1 relaxation, measured as %T1 change. In vitro assessment of the anti-DMPO probe indicated a significant decrease (p < 0.0001) in T1 relaxation in GL261 cells that were oxidatively stressed with hydrogen peroxide, compared to controls. The biotin moiety of the anti-DMPO probe was targeted with fluorescently-labeled streptavidin to locate the anti-DMPO probe in excised brain tissues. As a negative control a non-specific IgG antibody covalently bound to the albumin–Gd-DTPA–biotin construct was used. DMPO adducts were also confirmed in tumor tissue from animals administered DMPO, compared to non-tumor brain tissue. GL261 gliomas were found to have significantly increased malondialdehyde (MDA) protein adducts (p < 0.001) and 3-nitrotyrosine (3-NT) (p < 0.05) compared to normal mouse brain tissue, indicating increased oxidized lipids and proteins, respectively. Co-localization of the anti-DMPO probe with either 3-NT or 4-hydroxynonenal was also observed. This is the first report regarding the detection of in vivo levels of free radicals from a glioma model. 相似文献
993.
994.
The human B12 trafficking chaperone hCblC is well conserved in mammals and non-mammalian eukaryotes. However, the C-terminal ∼40 amino acids of hCblC vary significantly and are predicted to be deleted by alternative splicing of the encoding gene. In this study, we examined the thermostability of the bovine CblC truncated at the C-terminal variable region (t-bCblC) and its regulation by glutathione. t-bCblC is highly thermolabile (Tm = ∼42℃) similar to the full-length protein (f-bCblC). However, t-bCblC is stabilized to a greater extent than f-bCblC by binding of reduced glutathione (GSH) with increased sensitivity to GSH. In addition, binding of oxidized glutathione (GSSG) destabilizes t-bCblC to a greater extent and with increased sensitivity as compared to f-bCblC. These results indicate that t-bCblC is a more sensitive form to be regulated by glutathione than the full-length form of the protein. [BMB Reports 2013; 46(3): 169-174] 相似文献
995.
Jun Hyung Seo Hyo Geun Bae Da Hee Park Beom Seok Kim Jong Wook Lee Jung In Lee Dong Hyun Kim Seok Won Lee Bong Bo Seo 《Genes & genomics.》2013,35(1):117-124
Numerous studies on Oenothera species have been investigated for the physiological and ecological characteristics. However, no such an information based on molecular cytogenetic has yet been introduced, in turn, is very essential for identifying sequence polymorphisms of rRNA genes with their loci on mitotic phases for further biological researches. In this study, sequence variations of rRNA genes in Oenothera odorata and O. laciniata were examined to identify informative factors as unique or repeat sequences in intra- and inter-specific variations. Intra-specific variation revealed that the sequences of the rRNA genes including the spacer regions were highly conserved revealing only a few variations. From the inter-specific variation, spacer regions of species were completely different as (1) non-homologous sequences in NTS and (2) different type repeat sequences in ITS 1, 2 and 5.8S rRNA, whereas the remaining coding regions were highly conserved. FISH was carried out on mitotic phases using the 5S rDNA of the analyzed sequences. From the interphase and metaphase chromosomes of the examined species, two loci of 5S rDNA in O. odorata and four loci in O. laciniata were confirmed on the telomeric region of the short arm. Due to the small size and unclear centromere of the chromosomes, karyotype could not be completed. However, we confirmed that the chromosomes are organized by meta- and acrocentric chromosomes and the chromosomes with identified loci were assumed to be paired by the location of loci at the telomeric region on the short arm with relative lengths. 相似文献
996.
Kyong-Cheul Park Jae-Han Son Sung-II Lee Kwang-Soo Kim Young-Suk Chang Nam-Soo Kim 《Genes & genomics.》2013,35(6):787-794
Pong elements are active class 2 transposons in rice. We found Pong-like elements in Arabidopsis thaliana and named them as AtPong (Arabidopsis thaliana Pong) elements. The AtPong elements carried 13 bp of TIRs and two ORFs in which NAM DNA binding domain and DDE catalytic domain are encoded. Ping and mPing (miniature Ping) elements are deficient Pong elements and we found AtPong derived deficient AtPing and AtmPing elements. We also found a homologous element of the AtPong element in Brassica rapa. This element was a deficient element by internal deletion, but showed high sequence similarity with the AtmPing so that it was named as BrmPing (Brassica rapa miniature Ping). The AtPong, AtPing, and AtmPing elements were present in intergenic regions except one element, AtPing1, which was present in an exon of a F-box protein gene. Among the different A. thaliana ecotypes, the AtPing1 showed polymorphisms of present and absent in the F-box protein gene. The excision of the AtPing1 restored the expression of the F-box protein gene, indicating that the expression of the F-box protein genes is regulated by the AtPing1. 相似文献
997.
998.
Lee A. Rollins Angela T. Moles Serena Lam Robert Buitenwerf Joanna M. Buswell Claire R. Brandenburger Habacuc Flores‐Moreno Knud B. Nielsen Ellen Couchman Gordon S. Brown Fiona J. Thomson Frank Hemmings Richard Frankham William B. Sherwin 《Ecology and evolution》2013,3(13):4501-4517
Some introduced populations thrive and evolve despite the presumed loss of diversity at introduction. We aimed to quantify the amount of genetic diversity retained at introduction in species that have shown evidence of adaptation to their introduced environments. Samples were taken from native and introduced ranges of Arctotheca populifolia and Petrorhagia nanteuilii. Using microsatellite data, we identified the source for each introduction, estimated genetic diversity in native and introduced populations, and calculated the amount of diversity retained in introduced populations. These values were compared to those from a literature review of diversity in native, confamilial populations and to estimates of genetic diversity retained at introduction. Gene diversity in the native range of both species was significantly lower than for confamilials. We found that, on average, introduced populations showing evidence of adaptation to their new environments retained 81% of the genetic diversity from the native range. Introduced populations of P. nanteuilii had higher genetic diversity than found in the native source populations, whereas introduced populations of A. populifolia retained only 14% of its native diversity in one introduction and 1% in another. Our literature review has shown that most introductions demonstrating adaptive ability have lost diversity upon introduction. The two species studied here had exceptionally low native range genetic diversity. Further, the two introductions of A. populifolia represent the largest percentage loss of genetic diversity in a species showing evidence of substantial morphological change in the introduced range. While high genetic diversity may increase the likelihood of invasion success, the species examined here adapted to their new environments with very little neutral genetic diversity. This finding suggests that even introductions founded by small numbers of individuals have the potential to become invasive. 相似文献
999.
Bärbel Ulmer Cathrin Hagenlocher Silke Schmalholz Sabrina Kurz Axel Schweickert Ayelet Kohl Lee Roth Dalit Sela-Donenfeld Martin Blum 《Cell reports》2013,3(3):615-621
Highlights? Cnn2 is expressed in NCCs and required for their migration in frogs and chicks ? Cnn2 is inactivated by noncanonical Wnt signaling ? Loss of Cnn2 causes a switch from cortical actin to central stress fibers ? Cnn2 polarizes the actin cytoskeleton downstream of PCP 相似文献
1000.
Cynthia?M?MagroEmail author Xuan?Wang Francine?Garrett-Bakelman Jeffrey?Laurence Lee?S?Shapiro Maria?T?DeSancho 《Orphanet journal of rare diseases》2013,8(1):185