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101.
Kawasumi M Anzai M Takehara T Mitani T Kato H Saeki K Iritani A Matsumoto K Hosoi Y 《The Journal of reproduction and development》2007,53(3):615-622
The majority of somatic cell nuclear transferred (SCNT) embryos die before or after implantation. Many studies have focused on morphological remodeling of the donor nucleus and its associated cytoskeletal structures in the early events of nuclear transfer. However, little is known about the 2-cell stage of SCNT embryos after the first division. In this study, we compared the morphological status of chromosomal division during the 1-cell stage to the 2-cell stage in SCNT embryos with that in intracytoplasmic sperm injection (ICSI) embryos. The microtubules and cytoplasmic asters, which are related to chromatin segregation, disappeared at the pronuclear stage, although formation of the first mitotic spindle was normal in both the SCNT and ICSI embryos. However, nuclear fragmentation was observed in 30% of the 2-cell SCNT embryos and 12% of the 2-cell ICSI embryos. Nuclear fragmentation was present in both blastomeres of these embryos. No apoptotic DNA fragmentation was observed in TdT-mediated dUTP-biotin Nick End Labeling (TUNEL) assays for either the SCNT or ICSI embryos. In both the SCNT and ICSI embryos, the distribution of chromosomes in the first mitotic spindle was disturbed during the process of division from the 1-cell stage to the 2-cell stage. These results suggest that loss of SCNT embryos just before or after implantation may be due to an abnormal chromosome distribution at the 2-cell stage. 相似文献
102.
Hori Y Takusagawa F Ikadai H Uechi M Hoshi F Higuchi S 《American journal of veterinary research》2007,68(10):1058-1063
OBJECTIVE: To investigate the diuretic effects, tolerability, and adverse effects of furosemide and torsemide after short- and long-term administration in healthy dogs. ANIMALS: 8 mixed-breed dogs. PROCEDURES: In a crossover study, furosemide (2 mg/kg), torsemide (0.2 mg/kg), or placebo (bifidobacterium [1 mg/kg]) was administered orally to each dog every 12 hours for 14 days. Blood and urine samples were collected before the study (baseline data) and at intervals on the 1st (short-term administration) and 14th day (long-term administration) of treatment for assessment of urine volume and specific gravity and selected clinicopathologic variables including BUN, creatinine, and aldosterone concentrations, and creatinine clearance. RESULTS: Compared with the baseline value, short-term administration of furosemide or torsemide immediately increased urine volume significantly; after long-term administration of either drug, urine specific gravity decreased significantly. Compared with the effect of placebo, the 24-hour urine volume was significantly increased after short-term administra-tion of furosemide or torsemide. In addition, it was significantly increased after long-term administration of torsemide, compared with that of short-term administration. Long-term administration of furosemide or torsemide increased the BUN and plasma creatinine con-centrations, compared with the baseline value. Compared with the baseline value, plasma aldosterone concentration was significantly increased after long-term administration of either drug and was significantly higher after torsemide treatment than after furosemide treatment. CONCLUSIONS AND CLINICAL RELEVANCE: In dogs, diuretic resistance developed after 14 days of furosemide, but not torsemide, administration; however, both loop diuretics were associated with increased BUN and plasma creatinine concentrations, compared with values before treatment. 相似文献
103.
Manabu TANABE Hiroshi TAMURA Toshiaki TAKETANI Maki OKADA Lifa LEE Isao TAMURA Ryo MAEKAWA Hiromi ASADA Yoshiaki YAMAGATA Norihiro SUGINO 《The Journal of reproduction and development》2015,61(1):35-41
Melatonin protects luteinized granulosa cells (GCs) from oxidative stress in the follicle during ovulation. However, it is unclear in which cellular components (e.g., nuclei, mitochondria, or plasma membranes) melatonin works as an antioxidant. GCs from immature (3 wks) ICR mice were incubated with hydrogen peroxide (H2O2; 0.01, 0.1, 1, 10 mM) in the presence or absence of melatonin (100 μg/ml) for 2 h. DNA damage was assessed by fluorescence-based immunocytochemistry using specific antibodies for 8-hydroxydeoxyguanosine (8-OHdG), an indicator of oxidative guanine base damage in DNA, and for histone H2AX phosphorylation (γH2AX), a marker of double-strand breaks of DNA. Mitochondrial function was assessed by the fluorescence intensity of MitoTracker Red probes, which diffuse across the membrane and accumulate in mitochondria with active membrane potentials. Lipid peroxidation of plasma membranes was analyzed by measuring hexanoyl-lysine (HEL), a oxidative stress marker
for lipid peroxidation. Apoptosis of GCs was assessed by nuclear fragmentation using DAPI staining, and apoptotic activities were evaluated by caspase-3/7 activities. H2O2 treatment significantly increased the fluorescence intensities of 8-OHdG and γH2AX, reduced the intensity of MitoTracker Red in the mitochondria, increased HEL concentrations in GCs, and enhanced the number of apoptotic cells and caspase-3/7 activities. All these changes were significantly decreased by melatonin treatment. Melatonin reduced oxidative stress-induced DNA damage, mitochondrial dysfunction, lipid peroxidation, and apoptosis in GCs, suggesting that melatonin protects GCs by reducing oxidative stress of cellular components including nuclei, mitochondria, and plasma membranes. Melatonin helps to maintain the integrity of GCs as an antioxidant in the preovulatory follicle. 相似文献
104.
Noboru KUDO Natsumi ISHIKAWA Aki YAMANE Hiromi IKADAI Takashi OYAMADA 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2015,77(1):113-116
Gongylonema pulchrum is an important parasite of captive
primates. Twelve rabbits were infected with 30 third-stage larvae of G.
pulchrum. At 4–7 months post-infection, animals were administered levamisole at
a single dose of 12 mg/kg, levamisole at 8 mg/kg three times at 2-day intervals,
levamisole at a single dose of 8 mg/kg after administration of mebendazole at 70 mg/kg for
3 days or 8 ml of distilled water for 3 days (control). Necropsy at 14
days after treatment revealed that single and multiple dosages of levamisole reduced
nematode burdens by 68.4% and 89.5%, respectively. The combined regimen of mebendazole and
levamisole exhibited high efficacy for treating G. pulchrum located
widely within the upper digestive tract, with a reduction of 98.2%. These results suggest
that this combined chemotherapy treatment may be effective against G.
pulchrum infection, including buccal and lingual gongylonemiasis in
primates. 相似文献
105.
Chun Lan Lian Hiromi Yokota Gang Wang Shigeki Konishi 《Soil Science and Plant Nutrition》2013,59(2):261-264
Although zinc (Zn) is an essential element for the growth of higher plants, excess supply may lead to growth inhibition. Symptoms of Zn toxicity are characterized by a reduction in root growth and leaf expansion followed by chlorosis (Mengel and Kirkby 1987), especially root elongation is severely inhibited (Godbold et al. 1983). Due to the increase of input of Zn to farmland by the application of sewage sludge or large amounts of Zn-containing pig manure, Zn toxicity may become an important problem in certain regions (Ruano et al. 1987). In addition, Zn toxicity is also a problem in some acidic soils (Takahashi et al. 1980). Increasing soil pH by liming is the most effective procedure for decreasing both Zn content and Zn toxicity in plants (White et al. 1979), because Zn solubility decreases 100 times for each unit increase in pH (Neue and Lantin 1994). As an alternative approach, application of large amounts of phosphorus (P) fertilizer was employed to detoxify Zn (Takahashi et al. 1980). However, the mechanisms responsible for the detoxification of the excess Zn by P is remained to be elucidated. Interactions between Zn and P, which may occur in the rhizosphere and in the uptake and translocation processes, are complex. To separate these factors, in the present study, pollen tubes of tea (Camellia sinensis L.) were used as a model, and the efrect of P on pollen tube growth under Zn toxicity was studied. 相似文献
106.
Takashi Tsukamoto Hiroshi Uchida Hiromi Nakanishi Shingo Nishiyama Hideo Tsukada Shinpei Matsuhashi 《Soil Science and Plant Nutrition》2013,59(7):1085-1088
5-Aminolevulinic acid (ALA) acts to increase chlorophyll biosynthesis, photosynthesis, cold stress tolerance, and salt tolerance at low concentrations. We studied the effects of ALA on H2 15O translocation from the roots to the shoots of rice plants (Oryza sativa L. cv. Nipponbare) in real time by a positron-emitting tracer imaging system (PETIS). When the plant was treated with 10 μm ALA, the velocity of the H2 15O translocation from 2 to 12 min after absorption increased to 126, 137, 140% that of the control at 1.5, 2.5, and 3.5 h after ALA treatment, respectively. However, ALA did not affect the H2 15O translocation within 0.5 h of treatment. When the plant was treated with 0.1 mM ABA at 4 h after 10 μm ALA treatment, the velocity of the H2 15O translocation decreased at 0.5 h after ABA treatment. Those observations suggested ALA might be absorbed and transported to the guard cells within 1.5 h and functioned to expand the stomatal aperture. 相似文献
107.
108.
Shingo SUZUKI Kazuyoshi HOSOMICHI Kana YOKOYAMA Kaoru TSUDA Hiromi HARA Yutaka YOSHIDA Akira FUJIWARA Makoto MIZUTANI Takashi SHIINA Tomohiro KONO Kei HANZAWA 《Animal Science Journal》2013,84(1):90-96
Based on sequences of two cosmid clones from Japanese quail (Coturnix japonica, Coja), we confirmed that the syntenic cluster, GNB2L1~BTN1~BTN2, is located in the quail TRIM subregion of the quail major histocompatibility complex (MHC Coja) region. These cosmids also included four CjBG loci and one CjLEC locus; therefore, the quail TRIM subregion was thought to be adjacent to the BG/LEC subregion. We then identified three polymorphic markers – CjHEP21, CjTRIM39.2 and CjBTN2 – in the TRIM subregion that may be useful for the functional analysis of the MHC‐Coja region. We examined MHC‐Coja sequences from 321 individual quails sampled from 11 inbred strains, and we found eight alleles for each of the three genes – CjHEP21, CjTRIM39.2 and CjBTN2. These polymorphisms represent the first avian DNA markers in the TRIM subregion. Additionally, we discovered a quail‐specific VNTR (variable number of long tandem repeats, 133–137 bp) in intron 7 of CjBTN2. We identified 25 haplotypes in the sample of 321 quail; these haplotypes comprised combinations of all 24 alleles of the three polymorphic genes. We suggest that there are two recombination hotspots, one between each pair of adjacent loci. All strains, except AMRP, contained multiple haplotypes; the AMRP strain contained a single, apparently fixed haplotype. 相似文献
109.
110.
Iijima H Musumi K Hada T Maeda N Yonezawa Y Yoshida H Mizushina Y 《Journal of agricultural and food chemistry》2006,54(5):1627-1632
We investigated the effective extraction of monogalactosyldiacylglycerol (MGDG) from dried spinach (Spinacia oleracea) using supercritical fluid carbon dioxide (SC-CO(2)) with a modifier/entrainer. The yield of MGDG in the SC-CO(2) extract was not influenced by increasing temperature at a constant pressure, although the total extract yield was decreased. The total extract yield and MGDG yield in the extract from commercially purchased spinach (unknown subspecies), were greatly influenced by lower pressure. In a modifier (i.e., ethanol) concentration range of 2.5-20%, both the extract and MGDG yield increased as the ethanol concentration rose. The highest total extract yield (69.5 mg/g of spinach) and a good MGDG yield (16.3 mg/g of spinach) were obtained at 80 degrees C, 25 MPa, and 20% ethanol. The highest MGDG concentration (76.0% in the extract) was obtained at 80 degrees C, 25 MPa, and 2.5% ethanol, although the total extract yield under these conditions was low (5.2 mg/g of spinach). The optimal conditions for the extraction of MGDG were 80 degrees C, 20 MPa, and 10% ethanol. Of the 11 subspecies of spinach tested under these conditions, "Ujyou" had the highest concentration of MGDG. The total extract yield and MGDG concentration of Ujyou were 20.4 mg of the extract/g of spinach and 70.5%, respectively. The concentration of MGDG was higher in the SC-CO(2) extract than in the extract obtained using solvents such as methanol and n-hexane. The extract of Ujyou, which was the optimal subspecies for the extraction of MGDG, inhibited the activity of calf DNA polymerase alpha with IC(50) values of 145 microg/mL but was not effective against DNA polymerase beta. 相似文献