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1.
A full-length rabbit cDNA of cardiac adriamycin responsive protein (CARP) has been cloned. It shows high levels of identity at the amino acid sequence level (>86%) with the rat, mouse and human homologues. CARP mRNA levels are highly regulated in adriamycin-cardiomyopathy in rabbits.  相似文献   
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The homeobox protein, PEPP2 (RHOXF2), has been suggested as a cancer/testis (CT) antigen based on its expression pattern. However, the peptide epitope of PEPP2 that is recognized by cytotoxic T cells (CTLs) is unknown. In this study, we revealed that PEPP2 gene was highly expressed in myeloid leukemia cells and some other hematological malignancies. This gene was also expressed in leukemic stem-like cells. We next identified the first reported epitope peptide (PEPP2271-279). The CTLs induced by PEPP2271-279 recognized PEPP2-positive target cells in an HLA-A*24:02-restricted manner. We also found that a demethylating agent, 5-aza-2’-deoxycytidine, could enhance PEPP2 expression in leukemia cells but not in blood mononuclear cells from healthy donors. The cytotoxic activity of anti-PEPP2 CTL against leukemic cells treated with 5-aza-2’-deoxycytidine was higher than that directed against untreated cells. These results suggest a clinical rationale that combined treatment with this novel antigen-specific immunotherapy together with demethylating agents might be effective in therapy-resistant myeloid leukemia patients.  相似文献   
4.

Objective

We examined metabolic and endocrine responses during rest and exercise in moderate hypoxia over a 7.5 h time courses during daytime.

Methods

Eight sedentary, overweight men (28.6±0.8 kg/m2) completed four experimental trials: a rest trial in normoxia (FiO2 = 20.9%, NOR-Rest), an exercise trial in normoxia (NOR-Ex), a rest trial in hypoxia (FiO2 = 15.0%, HYP-Rest), and an exercise trial in hypoxia (HYP-Ex). Experimental trials were performed from 8:00 to 15:30 in an environmental chamber. Blood and respiratory gas samples were collected over 7.5 h. In the exercise trials, subjects performed 30 min of pedaling exercise at 60% of VO2max at 8:00, 10:30, and 13:00, and rested during the remaining period in each environment. Standard meals were provided at 8:30, 11:00, and 13:30.

Results

The areas under the curves for blood glucose and serum insulin concentrations over 7.5 h did not differ among the four trials. At baseline, %carbohydrate contribution was significantly higher in the hypoxic trials than in the normoxic trials (P<0.05). Although exercise promoted carbohydrate oxidation in the NOR-Ex and HYP-Ex trials, %carbohydrate contribution during each exercise and post-exercise period were significantly higher in the HYP-Ex trial than in the NOR-Ex trial (P<0.05).

Conclusion

Three sessions of 30 min exercise (60% of VO2max) in moderate hypoxia over 7.5 h did not attenuate postprandial glucose and insulin responses in young, overweight men. However, carbohydrate oxidation was significantly enhanced when the exercise was conducted in moderate hypoxia.  相似文献   
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The interactions of green or red light with blue light on the dark closing of Albizzia julibrissin Durazz. pinnules have been investigated. Irradiations at 430, 450 and 470 nm progressively delay dark closing with increasing photon fluence rates. Red or green light alone has no effect. However, when the blue fluence rate is low, both red and green light interact with it and increase the delaying effect of the blue light. When the blue fluence rate is high, green light interacts with it to negate some of the effectiveness of the blue light, while red light has no effect. This is similar to results obtained previously with far-red light. It is suggested that the same unidentified photoreceptor is operating in both the far-red and blue regions. The results also indicate the presence of a blue-only absorbing photoreceptor whose action is increased by phytochrome.  相似文献   
7.
During development, progenitor cell survival is essential for proper tissue functions, but the underlying mechanisms are not fully understood. Here we show that ERCC6L2, a member of the Snf2 family of helicase-like proteins, plays an essential role in the survival of developing chick neural cells. ERCC6L2 expression is induced by the Sonic Hedgehog (Shh) signaling molecule by a mechanism similar to that of the known Shh target genes Ptch1 and Gli1. ERCC6L2 blocks programmed cell death induced by Shh inhibition and this inhibition is independent of neural tube patterning. ERCC6L2 knockdown by siRNA resulted in the aberrant appearance of apoptotic cells. Furthermore, ERCC6L2 cooperates with the Shh signal and plays an essential role in the induction of the anti-apoptotic factor Bcl-2. Taken together, ERCC6L2 acts as a key factor in ensuring the survival of neural progenitor cells.  相似文献   
8.
Fujihira T  Kishida R  Fukui Y 《Cryobiology》2004,49(3):286-290
In the present study, effects of concentration and pretreatment time of cytochalasin B (CB), and of two types of cryoprotectant solutions on the nuclear maturation of vitrified-warmed porcine oocytes were examined. Also, the developmental capacity of vitrified immature porcine oocytes following intracytoplasmic sperm injection (ICSI) was investigated. The nuclear maturation rate (46.8%) of the vitrified-warmed oocytes treated with 7.5 microg/mL CB for 30 min was significantly higher (P < 0.05) than those (13.9-39.2%) of the vitrified-warmed oocytes treated with 0, 2.5, or 5.0 microg/mL CB for 10 or 30 min. Additionally, the nuclear maturation rate of oocytes treated with CB and vitrified in ethylene glycol (EG) (37.1%) was significantly higher (P < 0.05) than that of EG + dimethyl sulfoxide (Me(2)SO) (23.9%). However, no significant differences were observed in the cleavage and blastocyst development rates among the control (45.2 and 20.0%, respectively), the EG group (37.8 and 13.5%, respectively) and the EG + Me(2)SO group (39.3 and 14.3%, respectively). These results demonstrated that: (1) pretreatment with 7.5 microg/mL CB was beneficial for the vitrification of immature porcine oocytes; (2) the combination of EG and Me(2)SO as a cryoprotectant was not advantageous for in vitro maturation (IVM) of vitrified immature porcine oocytes; and (3) vitrified-warmed porcine oocytes matured after IVM, developed to the blastocyst stage without distinct differences compared to fresh oocytes following ICSI.  相似文献   
9.
Dorsal and ventral specification in the early optic vesicle plays a crucial role in vertebrate ocular morphogenesis, and proper dorsal‐ventral polarity in the optic vesicle ensures that distinct structures develop in separate domains within the eye primordium. The polarity is determined progressively during development by coordinated regulation of extraocular dorsal and ventral factors. In the present study, we cultured discrete portions of embryonic chick brains by preparing anterior cephalon, anterior dorsal cephalon and anterior ventral cephalon, and clearly demonstrate that bone morphogenetic protein 4 (BMP4) and Sonic hedgehog (Shh) constitute a dorsal‐ventral signaling system together with fibroblast growth factor 8 (FGF8). BMP4 and Shh upregulate Tbx5 and Pax2, as reported previously, and at the same time Shh downregulates Tbx5, while BMP4 affects Pax2 expression to downregulate similarly. Shh induces Fgf8 expression in the ventral optic vesicle. This, in turn, determines the distinct boundary of the retinal pigmented epithelium and the neural retina by suppressing Mitf expression. The lens develops only when signals from both the dorsal and ventral regions come across together. Inverted deposition of Shh and BMP4 signals in organ‐cultured optic vesicle completely re‐organized ocular structures to be inverted. Based on these observations we propose a novel model in which the two signals govern the whole of ocular development when they encounter each other in the ocular morphogenic domain.  相似文献   
10.
Lycopene has a large number of geometric isomers caused by E/Z isomerization at arbitrary sites within the 11 conjugated double bonds, offering varying characteristics related to features such as antioxidant capacity and bioavailability. However, the geometric structures of only a few lycopene Z-isomers have been thoroughly identified from natural sources. In this study, seven multi-Z-isomers of lycopene, (9Z,13′Z)-, (5Z,13Z,9′Z)-, (9Z,9′Z)-, (5Z,13′Z)-, (5Z,9′Z)-, (5Z,9Z,5′Z)-, and (5Z,9Z)-lycopene, were obtained from tomato samples by thermal isomerization, and then isolated by elaborate chromatography, and fully assigned using proton nuclear magnetic resonance. Moreover, the theoretically preferred pathway from (all-E)-lycopene to di-Z-isomers was examined with a computational approach using a Gaussian program. Fine-tuning of the HPLC separation conditions led to the discovery of novel multi-Z-isomers, and whose formation was supported by advanced theoretical calculations.  相似文献   
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