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121.
Ghanem M Yoshida C Isobe N Nakao T Yamashiro H Kubota H Miyake Y Nakada K 《Theriogenology》2004,61(7-8):1205-1213
Atresia ani, a common genetic defect in animals, is often accompanied by urogenital defects in calves. This paper reports a case of atresia ani with diphallus and separate scrota in a calf. The calf was born with atresia ani; surgery (to open the anus) was performed 3 days after birth. No urogenital abnormalities were noticed until 4 months after birth. At that time, two separate scrota (each containing a testis) and a sac-like structure in the middle of two scrota, were visible. The gait was abnormal, with abduction of the hind limbs while walking. Additionally, the hind legs appeared wider than usual at the hip joints. Two weeks later, two peni (diphallia) was observed, each in a separate preputial sheath. The calf had a normal karyotype on cytogenetic examination. Plasma concentrations of testosterone at 5.5, 6, and 7 months of age were 3.5, 1.9, and 1.7 ng/ml, respectively. At necropsy (7 months of age), the prepuce was thick and the glans of the right penis was adhered to the prepuce. The left penis did not have a urethra or retractor penis muscles. The sac-like structure in the middle of the two scrota contained the urinary bladder and a loop of small intestine. The pubic bone had failed to fuse at the pelvic symphysis. In conclusion, this is the first reported case of atresia ani with diphallus, separate scrota, and pubic bone separation in a calf. 相似文献
122.
Luteal function and conception in lactating cows and some factors influencing luteal function after first insemination 总被引:1,自引:0,他引:1
The objective of this study was to investigate the types and incidence of luteal sub-function in lactating cows after artificial insemination (AI) and their relationship with pregnancy, and to clarify the relationship between luteal function and parity, body condition score (BCS), milk yield, and dietary intake. In 19 cows, milk samples were collected daily from AI to confirmation of pregnancy. Milk progesterone concentrations were determined by EIA. Based on peak progesterone concentration and the day of onset of luteal phase, 15 of 30 progesterone profiles (50%) were normal, with progesterone concentration reaching 1.0 ng/ml within 5 days after insemination and > or =2.0 ng/ml thereafter. In addition, 6 (20%) were insufficient, (progesterone concentration remained < 2.0 ng/ml), 5 (17%) were delayed (progesterone reached 1.0 ng/ml after 5 days), 2 (7%) were both delayed and insufficient, one (3%) was short (progesterone >1.0 ng/ml for only 7 days), and one (3%) remained basal. Cows with a normal profile had a higher (P < 0.05) pregnancy rate than those with an abnormal profile (87% versus 33%, respectively). The amount of progesterone secreted in milk after first AI, as indicated by progesterone area under curve (AUC), was negatively correlated with milk yield (r = -0.83, P < 0.01), dry matter intake (r = -0.81, P < 0.05), total digestible nutrients (r = -0.82, P< 0.05), and digestible crude protein (r = -0.79, P <0.05). Cows that produced more milk and consumed more dry matter had less progesterone during the luteal phase. In conclusion, abnormal luteal function was associated with reduced pregnancy rates and high milk production and increased dietary intake during breeding were associated with reduced progesterone concentrations. 相似文献
123.
Rad18 guides poleta to replication stalling sites through physical interaction and PCNA monoubiquitination 总被引:1,自引:0,他引:1
Watanabe K Tateishi S Kawasuji M Tsurimoto T Inoue H Yamaizumi M 《The EMBO journal》2004,23(19):3886-3896
The DNA replication machinery stalls at damaged sites on templates, but normally restarts by switching to a specialized DNA polymerase(s) that carries out translesion DNA synthesis (TLS). In human cells, DNA polymerase eta (poleta) accumulates at stalling sites as nuclear foci, and is involved in ultraviolet (UV)-induced TLS. Here we show that poleta does not form nuclear foci in RAD18(-/-) cells after UV irradiation. Both Rad18 and Rad6 are required for poleta focus formation. In wild-type cells, UV irradiation induces relocalization of Rad18 in the nucleus, thereby stimulating colocalization with proliferating cell nuclear antigen (PCNA), and Rad18/Rad6-dependent PCNA monoubiquitination. Purified Rad18 and Rad6B monoubiquitinate PCNA in vitro. Rad18 associates with poleta constitutively through domains on their C-terminal regions, and this complex accumulates at the foci after UV irradiation. Furthermore, poleta interacts preferentially with monoubiquitinated PCNA, but poldelta does not. These results suggest that Rad18 is crucial for recruitment of poleta to the damaged site through protein-protein interaction and PCNA monoubiquitination. 相似文献
124.
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126.
Production of transgenic rats by ooplasmic injection of spermatogenic cells exposed to exogenous DNA: a preliminary study 总被引:5,自引:0,他引:5
Kato M Ishikawa A Kaneko R Yagi T Hochi S Hirabayashi M 《Molecular reproduction and development》2004,69(2):153-158
The aim of the present study was to investigate the efficiencies of producing transgenic rats by the ooplasmic injection of sperm heads (intracytoplasmic sperm injection: ICSI) and elongating spermatids (elongating spermatid injection: ELSI) exposed to the EGFP DNA solution. A slightly lower proportion of ICSI oocytes using sperm heads exposed to a concentration of 0.5 microg/ml DNA solution for 1 min developed into offspring (13.3%, 48/361) when compared to that of oocytes injected with nontreated sperm heads (19.4%, 32/165). Eight ICSI offspring were found to be EGFP-carrying transgenic rats (16.7% per offspring; 2.2% per embryo). After a 1-min exposure of the elongating spermatids to 5 microg/ml of DNA solution, 8.8% (45/511) of the ELSI oocytes developed into offspring while 12.7% (22/173) of the ELSI oocytes using nontreated spermatids developed. Six ELSI offspring carried the EGFP DNA (13.3% per offspring; 1.2% per embryo). The conventional pronuclear microinjection of 5 microg/ml of DNA solution resulted in the higher production of offspring (29.7%, 104/350) and the birth of three transgenic rats (2.9% per offspring; 0.9% per embryo). Thus, sperm heads and elongating spermatids were practically useful as the vector of exogenous DNA if the DNA-exposed spermatogenic cells were microinseminated into rat oocytes. 相似文献
127.
Kubo K Ohyama S Shimizu T Takami A Murooka H Nishitoba T Kato S Yagi M Kobayashi Y Iinuma N Isoe T Nakamura K Iijima H Osawa T Izawa T 《Bioorganic & medicinal chemistry》2003,11(23):5117-5133
We discovered a new series of 4-phenoxyquinoline derivatives as potent and selective inhibitors of the platelet-derived growth factor receptor (PDGFr) tyrosine kinase. We researched the highly potent and selective inhibitors on the basis of both PDGFr and epidermal growth factor receptor (EGFr) inhibitory activity. First, we found a compound, Ki6783 (1), which inhibited PDGFr autophosphorylation at 0.13 microM, but it did not inhibit EGFr autophosphorylation at 100 microM. After extensive explorations, we found the two desired compounds, Ki6896 (2) and Ki6945 (3), which are substituted by benzoyl and benzamide at the 4-position of the phenoxy group on 4-phenoxyquinoline, respectively. These inhibitory activities were 0.31 and 0.050 microM, respectively, but neither of them inhibited EGFr autophosphorylation at 100 microM. We further investigated the profile of both compounds toward various tyrosine and serine/threonine kinases. The three compounds specifically inhibited PDGFr rather than the other kinases. 相似文献
128.
Aryl hydrocarbons such as dioxins, polychlorinated biphenyls and polyaromatic hydrocarbons bind to the cellular aryl hydrocarbon receptor (AhR) in the initial step of their metabolism. The activation of intracellular signaling subsequent to the AhR binding is highly correlated with the toxicity and carcinogenicity of these chemicals. We produced Saccharomyces cerevisiae coexpressing mouse AhR and aryl hydrocarbon receptor nuclear translocator (Arnt) protein in accordance with Miller III's method for constructing yeasts with human Ahr and Arnt [Toxicol. Appl. Pharmacol. 160 (1998) 297]. Ligand treatment induced a dose-dependent increase in beta-galactosidase activity from a reporter plasmid in the yeast. Then, we compared activities of several ligands in yeast having the mouse Ahr/Arnt genes with those in yeast having the human genes, both of which have the same genetic background. There was no significant difference in the EC50 values of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), benzo[a]pyrene, 3-methylcholanthrene and beta-naphthoflavone between the mouse and human genes. However, indirubin, which was recently found in human urine as a potent AhR ligand [J. Biol. Chem. 276 (2001) 31475], had a 35-140 times higher EC50 value in the yeast with human genes than mouse genes. This difference might reflect species-specificity between mouse and human AhR/Arnt. 相似文献
129.
Adenoviral transfection of hepatocytes with the thioredoxin gene confers protection against apoptosis and necrosis 总被引:3,自引:0,他引:3
Tsutsui T Koide H Fukahori H Isoda K Higashiyama S Maeda I Tashiro F Yamato E Miyazaki J Yodoi J Kawase M Yagi K 《Biochemical and biophysical research communications》2003,307(4):765-770
A recombinant adenovirus vector containing the human thioredoxin (TRX) gene was constructed using the Cre-loxP recombination system and used to transfect rat hepatocytes with very high efficiency. The TRX gene was expressed in a dose-dependent manner and significantly modulated rat cellular functions. The TRX gene conferred resistance to oxidative stress, such as hydrogen peroxide treatment, on the host hepatocytes. FACS analysis of DNA fragmentation showed that the TRX gene suppressed hepatocyte apoptosis. It also significantly extended the life span of hepatocytes cultured conventionally on polystyrene plates. Liver-specific functions were maintained in the viability-modulated hepatocytes. Moreover, TRX expression did not affect hepatocyte spheroid formation and it extensively suppressed necrosis in the internal cells. Thus, the transfection of hepatocytes with the TRX gene successfully confers global maintenance of liver functions. These findings provide important information for the development of bioartificial liver support systems and gene therapy for liver diseases. 相似文献
130.
Growth of and hydrogen production by wild-type (WT) Rhodovulum sulfidophilum were compared with those by one of its mutants lacking the poly(3-hydroxybutyrate) (PHB) biosynthesis ability (PNM2). During phototrophic growth under aerobic conditions with fixed illumination, changes in the extinction coefficient and PHB content of WT and PNM2 cells revealed interference of light penetration by PHB. WT cells synthesized PHB at an early stage of the cultivation. PHB degradation after exhaustion of acetate during the cultivation of WT resulted in a decrease of the extinction coefficient. The hydrogen production rate under anaerobic conditions with fixed illumination was examined in WT and PNM2 cell suspensions at different densities. The hydrogen production rate was determined not by the light penetration but by the kinds of hydrogen donors and the density of suspension. The highest value of the rate of hydrogen production from PHB, 33.0 ml/l/h, was improved compared with 26.6 ml/l/h, which was the highest value in hydrogen production from succinate. Under the same illumination, conversion to hydrogen from PHB is more efficient than that from succinate, which is one of the best substrates for hydrogen production. These results suggest that the hydrogen production rate can be maximized in the hydrogen production system based on PHB degradation, which is achieved in high-density suspension under external-substrate-depleted conditions after aerobic cultivation in the presence of an excess amount of acetate. 相似文献