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211.
Yoshiaki NAKAMURA Mariko TASAI Kumiko TAKEDA Keijiro NIRASAWA Takahiro TAGAMI 《The Journal of reproduction and development》2013,59(6):580-587
The Japanese quail (Coturnix japonica) is a valuable bird as both
an experimental animal, for a wide range of scientific disciplines, and an
agricultural animal, for the production of eggs and meat. Cryopreservation of PGCs
would be a feasible strategy for the conservation of both male and female fertility
cells in Japanese quail. However, the effects of freeze-thaw treatment on viability,
migration ability and germline transmission ability of quail PGCs still remain
unclear. In the present study, male and female PGCs were isolated from the blood of
2-day-old embryos, which were cooled by slow freezing and then cryopreserved at –196
C for 77–185 days, respectively. The average recovery rate of PGCs after
freeze-thawing was 47.0%. The viability of PGCs in the frozen group was significantly
lower than that of the control group (P<0.05) (85.5% vs. 95.1%).
Both fresh and Frozen-thawed PGCs that were intravascularly transplanted into
recipient embryos migrated toward and were incorporated into recipient gonads,
although the number of PGCs settled in the gonads was 48.5% lower in the frozen group
than in the unfrozen control group (P<0.05). Genetic cross analysis revealed that
one female and two male recipients produced live progeny derived from the
frozen-thawed PGCs. The frequency of donor-derived offspring was slightly lower than
that of unfrozen controls, but the difference was not significant (4.0
vs. 14.0%). These results revealed that freeze-thaw treatment
causes a decrease in viability, migration ability and germline transmission ability
of PGCs in quail. 相似文献
212.
Kumiko M Kimura Takashi Yokoyama Makoto Haritani Minoru Narita Peter Belleby Julie Smith Yvonne I Spencer 《Journal of veterinary diagnostic investigation》2002,14(3):255-257
To detect prion protein, brains from 5 cattle naturally affected with bovine spongiform encephalopathy (BSE) and 3 sheep naturally affected with scrapie were examined and compared with brains of normal cattle and sheep using a histoblot technique. The technique enabled the in situ distinctive detection of the cellular (PrP(C)) and abnormal (PrP(Sc)) isoforms of the prion protein. In BSE- or scrapie-affected brains, the Prp(C) signal decreased, especially in those areas where the PrP(Sc) signal was detected. 相似文献
213.
214.
Food production and the energy crisis 总被引:1,自引:0,他引:1
Pimentel D Hurd LE Bellotti AC Forster MJ Oka IN Sholes OD Whitman RJ 《Science (New York, N.Y.)》1973,182(4111):443-449
The principal raw material of modern U.S. agriculture is fossil fuel, whereas the labor input is relatively small (about 9 hours per crop acre). As agriculture is dependent upon fossil energy, crop production costs will also soar when fuel costs increase two- to fivefold. A return of 2.8 kcal of corn per 1 kcal of fuel input may then be uneconomical. Green revolution agriculture also uses high energy crop production technology, especially with respect to fertilizers and pesticides. While one may not doubt the sincerity of the U.S. effort to share its agricultural technology so that the rest of the world can live and eat as it does, one must be realistic about the resources available to accomplish this mission. In the United States we are currently using an equivalent of 80 gallons of gasoline to produce an acre of corn. With fuel shortages and high prices to come, we wonder if many developing nations will be able to afford the technology of U.S. agriculture. Problems have already occurred with green revolution crops, particularly problems related to pests (57). More critical problems are expected when there is a world energy crisis. A careful assessment should be made of the benefits, costs, and risks of high energy-demand green revolution agriculture in order to be certain that this program will not aggravate the already serious world food situation (58). To reduce energy inputs, green revolution and U.S. agriculture might employ such alternatives as rotations and green manures to reduce the high energy demand of chemical fertilizers and pesticides. U.S. agriculture might also reduce energy expenditures by substituting some manpower currently displaced by mechanization. While no one knows for certain what changes will have to be made, we can be sure that when conventional energy resources become scarce and expensive, the impact on agriculture as an industry and a way of life will be significant. This analysis is but a preliminary investigation of a significant agricultural problem that deserves careful attention and greater study before the energy situation becomes more critical. 相似文献
215.
Tetsuya KOMATSU Erina YOSHIDA Ayumi SHIGENAGA Nozomi YASUIE Shintaro UCHIYAMA Yuji TAKAMURA Kennosuke SUGIE Kumiko KIMURA Makoto HARITANI Tomoyuki SHIBAHARA 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2021,83(7):1113
One calf died (No. 1) and another was euthanized following astasia (No. 2). Histopathological examination revealed suppurative meningoencephalitis in these calves. Klebsiella pneumoniae antigens were detected in lesions. Thymocytes were decreased in the thymus cortex in both cases. 16S rRNA gene sequencing of the No. 1 isolate and bacterial extracts from formalin fixed paraffin embedded sections of No. 2 revealed that both samples were K. pneumoniae. The No. 1 isolate showed multidrug resistance against penicillin antibiotics, fosfomycin, streptomycin, macrolide antibiotics, tetracycline antibiotics, and clindamycin. Immunosuppression is a significant septicemic K. pneumoniae infection risk factor. Our study provides new aspects regarding K. pneumoniae infections in cattle, bacterial meningoencephalitis differentiation, and K. pneumoniae and bacterial meningoencephalitis treatments. 相似文献
216.
Jun Murase Kumiko Itoh Mayuko Kana Makoto Kimura 《Soil Science and Plant Nutrition》2013,59(6):909-913
The structure of the β-proteobacterial autotrophic ammonia-oxidizing bacterial (AOB) communities in a microcosm of submerged paddy soil was determined by denaturing gradient gel electrophoresis (DGGE) analysis of 16S rRNA gene fragments amplified using AOB-selective primers. Shift in the community composition was observed 4 weeks after submergence. The communities from the surface layers (0–1, 2–3 mm) of the soil microcosm were different from those of the subsurface layers (6–9, > 15 mm) and DGGE bands specific to each layer were detected. The majority of the retrieved sequences were Nitrosospira-like, whereas no Nitrosomonas-like sequences were obtained. The 16S rDNA primer set also amplified sequences that were not related to the known Nitrosospira-Nitrosomonas group, although they showed a close relationship with other groups of β-proteobacteria. The results suggest that Nitrosospira-like populations are dominant AOB populations in the submerged paddy soil, and that the oxic layer of submerged paddy soil harbours the specific AOB. 相似文献
217.
Sodium transport to the shoots of rice (Oryza sativa L.) plants grown under salt stress conditions was characterized. The rate of Na+ transport to shoots increased exponentially depending on the increase in the NaCl concentration of the rooting solution, however, the rates were independent of the plant transpiration. Excessive NaCl in the rooting solution was found to enhance apoplastic transport in rice plants by using the apoplastic dye, 3-hydroxy-5,8,10-pyrene trisulfonic acid (PTS) and Fluostain I (also known as Calcoflour White M2R New). The results suggest that excessive Na+ in the rooting solution enlarges the apoplastic pathways, which facilitates Na+ intrusion into the xylem vessels, resulting in an excessive accumulation of Na+ in rice shoots. 相似文献
218.
Takeda K Srirattana K Matsukawa K Akagi S Kaneda M Tasai M Nirasawa K Pinkert CA Parnpai R Nagai T 《The Journal of reproduction and development》2012,58(3):323-329
Interspecies/intergeneric mitochondrial heteroplasmy can occur in interspecies/intergeneric hybrid embryos or following nuclear transfer. In the present study, intergeneric buffalo (Bubalus bubalis) mitochondria (WB-mt) or interspecies murine (Mus spretus) mitochondria (M-mt) were injected into bovine (Bos taurus) oocytes, and the subsequent embryonic development was characterized. Fibroblast mitochondria (WB-mt or M-mt) were microinjected into in vitro matured bovine oocytes followed by oocyte activation by a combination of electrical stimulation and 6-dimethylaminopurine treatment. After seven days of culture, embryo development was evaluated. The copy number of specific mtDNA populations (introduced and native mtDNA) from heteroplasmic oocytes was estimated using real-time PCR. The results illustrated that oocytes injected with either WB-mt or M-mt can develop to the blastocyst stage (20.6% and 19.6%). Cleavage division rates and development to the morula stage in oocytes injected with WB-mt were lower (76.2% and 45.9%, respectively) in comparison with uninjected oocytes (89.2% and 59.1%, respectively) (P<0.05). However, no differences were found in comparing M-mt injected oocytes and controls (P>0.05). An increase in bovine mtDNA copy number was observed at the expanded blastocyst stage of injected embryos (P<0.01), while the number of injected mtDNA was stable throughout development. This study demonstrates that interspecies/intergeneric mitochondrial injected bovine oocytes have the ability to develop to the blastocyst stage after parthenogenetic activation and that injected mtDNA was neither selectively destroyed nor enhanced through development. Moreover, injected intergeneric mitochondria had a demonstrated influence on bovine parthenogenetic development and mtDNA replication. 相似文献
219.
ABSTRACT Chemical inducers of pathogenesis-related proteins and plant resistance were applied to tomato plants, with the aim of inducing resistance to the root-knot nematode Meloidogyne javanica. Relative to control plants, foliar spray and soil-drenching with dl-beta-amino-n-butyric acid (BABA) reduced root-galling 7 days after inoculation, as well as the number of eggs 30 days after inoculation. Other chemicals (alpha- and gamma-amino-n-butyric acid, jasmonic acid, methyl jasmonate, and salicylic acid) were either phytotoxic to tomato plants or did not improve control of root-knot nematodes. Fewer second-stage juveniles invaded BABA-treated tomato roots, and root-galling indices were lower than in control tomato plants. Resistance phenomena in seedlings lasted at least 5 days after spraying with BABA. Nematodes invading the roots of BABA-treated seedlings induced small, vacuolate giant cells. Postinfection treatment of tomato plants with BABA inhibited nematode development. It is speculated that after BABA application tomato roots become less attractive to root-knot nematodes, physically harder to invade, or some substance(s) inhibiting nematode or nematode feeding-site development is produced in roots. 相似文献
220.