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951.
John J. Govoni James A. Morris Jr. David W. Evans 《Journal of aquatic animal health》2013,25(3):173-180
AbstractExposure to mercury (Hg) results in reproductive abnormalities and deficiencies in female fish. We traced the maternal assimilation and redistribution of dietary inorganic (HgII) and organic (MeHg) forms of Hg in a coastal marine fish, the Spot Leiostomus xanthurus. We conducted a 90-d laboratory experiment in which treatment Spot were fed muscle of Blue Marlin Makaira nigricans with elevated concentrations of Hg mixed with a commercial fish food, while control Spot were fed only commercial food pellets. Gonadal maturation was induced by shortening the photoperiod and increasing the temperature. Spawning was induced by intramuscular injection of human chorionic gonadotropin at 100 IU/kg. Solid-sampling atomic absorption spectrophotometry measured the total Hg (THg), HgII, and MeHg in Blue Marlin muscle. Autometallography located Hg-sulfide granules in the liver, ovaries, and spawned eggs, and densitometry provided comparisons of Hg-sulfide granules in the ovaries of treatment and control Spot. Overall, the intensity and prevalence of Hg-sulfide granules were greater in the liver, ovaries, and eggs from treatment Spot than in those from controls. The tissue and cellular distribution of Hg-sulfide granules differed.Received November 18, 2016; accepted June 18, 2017 Published online August 11, 2017 相似文献
952.
Delgado M. VALDEZ JR . Ryoma TSUCHIYA Shinsuke SEKI Naoya SAIDA Saori NIIMI Chihiro KOSHIMOTO Kazutsugu MATSUKAWA Magosaburo KASAI Keisuke EDASHIGE 《The Journal of reproduction and development》2013,59(2):205-213
Fish oocytes have not been cryopreserved successfully, probably because it is difficult
to prevent intracellular ice from forming. Previously, we have shown in medaka that
immature oocytes are more suitable for cryopreservation than mature oocytes or embryos, in
terms of permeability. We have also shown in immature medaka oocytes that the exogenous
expression of aquaporin 3 (AQP3), a water/cryoprotectant channel, promotes the movement of
water and cryoprotectants through the plasma membrane. In the present study, we attempted
to cryopreserve immature medaka oocytes expressing AQP3. We first examined effects of
hypertonic stress and the chemical toxicity of cryoprotectants on the survival of the
AQP3-expressing oocytes. Exposure to hypertonic solutions containing sucrose decreased the
survival of oocytes, but the expression of AQP3 did not affect sensitivity to hypertonic
stress. Also, AQP3 expression did not markedly increase sensitivity to the toxicity of
cryoprotectants. Of the four cryoprotectants tested, propylene glycol was the least toxic.
Using a propylene glycol-based solution, therefore, we tried to cryopreserve immature
oocytes by vitrification. During cooling with liquid nitrogen, all intact oocytes became
opaque, but many AQP3-expressing oocytes remained transparent. This indicates that the
expression of AQP3 is effective in preventing intracellular ice from forming during
cooling. During warming, however, all the AQP3-expressing oocytes became opaque,
indicating that intracellular ice formed. Therefore, the dehydration and permeation by
propylene glycol were still insufficient. Further studies are necessary to realize the
cryopreservation of fish oocytes. 相似文献
953.
Marshall A Bryant D Latypova G Hauck B Olyott P Morris P Robbins M 《Journal of agricultural and food chemistry》2008,56(3):974-981
Lotus corniculatus and Lotus uliginosus are agronomically important forage crops used in ruminant livestock production. The condensed tannin (CT) content, dry matter (DM) production, and persistence of these species are key characteristics of interest for future exploitation of these crops. Here we present field data on 19 varieties of L. corniculatus, 2 varieties of L. uliginosus and, additionally, a glasshouse experiment using 6 varieties of L. corniculatus and 2 varieties of L. uliginosus. Current methods for the quantification of condensed tannins in crop species are slow and labor intensive and are generally based upon polymer hydrolysis following the extraction of chlorophyll in a liquid phase. Presented here is a high-throughput protocol for condensed tannin quantification suitable for microtiter plates based upon the precipitation of condensed tannin polymers in complex with bovine serum albumin (BSA) with subsequent hydrolysis of precipates using butan 1-ol/ hydrochloric acid. 相似文献
954.
J. B. Morris 《Genetic Resources and Crop Evolution》2009,56(3):421-427
Butterfly pea, Clitoria ternatea is used in Africa as a companion crop and in the United States as an ornamental. The USDA, ARS, PGRCU curates 28 butterfly
pea accessions. Butterfly pea accessions were transplanted from about 30-day-old seedlings to the field in Griffin, GA around
01 June 1999, 2003, 2006–2007 or directly sown in 2001. At 50% maturity, 19 accessions were characterized for morphology,
phenology, and evaluated for regeneration. High quality plants regenerated from all accessions produced 6 to more than 3,400
total seeds. Butterfly pea can be successfully grown and regenerated in Griffin, GA. Coefficients of variation and principal
component analysis revealed considerable variability among accessions for morphological and reproductive traits. Butterfly
pea has potential to be used as a nutraceutical, pharmaceutical, or food. The flavonoid quercetin has been shown to reduce
upper respiratory infections in humans while delphinidin and malvidin identified in butterfly pea flowers may inhibit various
forms of cancer. 相似文献
955.
956.
Impact of Treated Industrial Effluent on Physical and Chemical Properties of Three Subtropical Soils and Millet Nutrition 总被引:2,自引:0,他引:2
Filipe Selau Carlos Andrei Marafon Robson Andreazza Lawrence A. Morris Marino José Tedesco Cácio Luiz Boechat 《Communications in Soil Science and Plant Analysis》2017,48(21):2514-2525
The use of treated industrial effluents to irrigate plants is an alternative, because of nutrients that can increase yield of the agricultural crops. This study was conducted to determine irrigation with treated effluent and gypsum application, which changes the chemical and physical characteristics of soils and the growth and nutrition of millet (Pennisetum glaucum). Thus, an experiment was conducted on PVC columns with three soil classes, Typic Hapludox, Typic Hapludult, and Arenic Hapludult. Nutrient and Na+ concentrations in the millet biomass reflected concentrations of elements in the effluent and soil. In the control, low N levels were found in the biomass, while higher leaf N concentrations were observed, due to irrigation with treated effluent. In the short term, irrigation with treated industrial effluent by controlled application could be an alternative and a complementary source of nutrients for plants, reducing the volume of nutrients and organic materials discharged into water bodies. 相似文献
957.
Matthew J. Atherton Samantha Vazquez‐Sanmartin Sam Sharpe Elspeth M. Waugh Joanna S. Morris 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》2017,46(3):520-525
A 10‐year‐old crossbred dog was presented with a 6‐week history of hematemesis, melena, anorexia, and lethargy. Clinical evaluation revealed a gastric mass with a regional lymphadenomegaly as well as a monoclonal gammopathy manifesting as hyperglobulinemia. Cytologic and histopathologic analyses were consistent with a round cell neoplasm; neoplastic cells showed nuclear immunoreactivity for MUM1 and diffuse cytoplasmic reactivity for CD3. Polymerase chain reactions performed on fixed and fresh tissue identified a clonal rearrangement with an IgH primer set. An extramedullary plasmacytoma (EMP) was confirmed by cellular morphology and molecular diagnostics. Following an objective response to chemotherapy, the dog was euthanized 8 months after diagnosis, and a postmortem examination confirmed the clinical findings. This is the first reported case of a monoclonal gammopathy secondary to a gastric EMP coupled with aberrant expression of CD3 in an aggressive plasmacytic tumor, and highlights the utility of molecular diagnostics for classifying atypical hemolymphoid neoplasms. 相似文献
958.
Iverson V Morris RM Frazar CD Berthiaume CT Morales RL Armbrust EV 《Science (New York, N.Y.)》2012,335(6068):587-590
Ecosystems are shaped by complex communities of mostly unculturable microbes. Metagenomes provide a fragmented view of such communities, but the ecosystem functions of major groups of organisms remain mysterious. To better characterize members of these communities, we developed methods to reconstruct genomes directly from mate-paired short-read metagenomes. We closed a genome representing the as-yet uncultured marine group II Euryarchaeota, assembled de novo from 1.7% of a metagenome sequenced from surface seawater. The genome describes a motile, photo-heterotrophic cell focused on degradation of protein and lipids and clarifies the origin of proteorhodopsin. It also demonstrates that high-coverage mate-paired sequence can overcome assembly difficulties caused by interstrain variation in complex microbial communities, enabling inference of ecosystem functions for uncultured members. 相似文献
959.
960.