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91.
Joshi A  Rajput S  Wang C  Ma J  Cao D 《Biological chemistry》2010,391(12):1371-1378
Aldo-keto reductase family 1 member B10 (AKR1B10), over-expressed in multiple human cancers, might be implicated in cancer development and progression via detoxifying cytotoxic carbonyls and regulating fatty acid synthesis. In the present study, we investigated the ortholog of AKR1B10 in mice, an ideal modeling organism greatly contributing to human disease investigations. In the mouse, there are three aldo-keto reductase family 1 subfamily B (AKR1B) members, i.e., AKR1B3, AKR1B7, and AKR1B8. Among them, AKR1B8 has the highest similarity to human AKR1B10 in terms of amino acid sequence, computer-modeled structures, substrate spectra and specificity, and tissue distribution. More importantly, similar to human AKR1B10, mouse AKR1B8 associates with murine acetyl-CoA carboxylase-α and mediates fatty acid synthesis in colon cancer cells. Taken together, our data suggest that murine AKR1B8 is the ortholog of human AKR1B10.  相似文献   
92.
ABSTRACT. By use of a monoclonal antibody directed against purified lectin from the sponge Geodia cydonium it was demonstrated that the mucocysts of Tetrahymena pyriformis contain a substance immunologically similar to that found in G. cydonium . In extracts of T. pyriformis the monoclonal antibody recognizes a 36 kDa protein; binding could be abolished by adsorption of the antibody with (i) crude extract, (ii) purified lectin from G. cydonium and (iii) a 29 aa long peptide. In addition the data show that 10-6 M of insulin causes first the release of mucocyst material, which reacts with the lectin antibody, and second its subsequent redistribution on the surface of the somatic cilia and the oral field.  相似文献   
93.
The occurrence of flattened stems in Rhynchosia phaseoloides (SW.) DC. (Fabaceae) has been known for years, but little interest has been shown toward elucidating its secondary growth. This study aims to (1) understand the pattern of secondary growth and development of vascular elements from the cambium at different stages of stem growth and (2) elucidate the type, size and distribution of cells related to these processes at different regions of the stem. Dilatation growth in main stems and branches of R. phaseoloides is achieved by successive cambia formed in two areas of the actual cortex that are opposed to each other by approximately 180°. Only the first cambial ring is functionally normal and closed-elliptical in outline, supporting the growth of the middle part of the rather flat stem. Later on, this stem becomes oval to oblong in cross-section outline by the activity of successive cambia from which cells produce further xylem, phloem and parenchyma tissues in a somewhat fan-shaped way. As shown in cross section, a flat cable-like structure of several modules results, forming wings relative to the primary central axis tissues. The secondary cambia are formed by dedifferentiation of cortical parenchyma cells, resulting in small clusters of radially arranged meristematic bands of cells. From these meristematic bands, an outward-facing crescent-shaped new band of cambium is originated. The innermost cells of this meristematic band form the parenchymatic tissue that connects the new lateral module to the proximal one. This occurs several times during the whole stem ontogeny.  相似文献   
94.
INTRODUCTION: The incidence of Barrett esophageal adenocarcinoma (BEAC) has been increasing at an alarming rate in western countries. In this study, we have evaluated the therapeutic potential of sulforaphane (SFN), an antioxidant derived from broccoli, in BEAC. METHODS: BEAC cells were treated with SFN, alone or in combination with chemotherapeutic, paclitaxel, or telomerase-inhibiting agents (MST-312, GRN163L), and live cell number determined at various time points. The effect on drug resistance/chemosensitivity was evaluated by rhodamine efflux assay. Apoptosis was detected by annexin V labeling and Western blot analysis of poly(ADP-ribose) polymerase cleavage. Effects on genes implicated in cell cycle and apoptosis were determined by Western blot analyses. To evaluate the efficacy in vivo, BEAC cells were injected subcutaneously in severe combined immunodeficient mice, and after the appearance of palpable tumors, mice were treated with SFN. RESULTS: SFN induced both time- and dose-dependent decline in cell survival, cell cycle arrest, and apoptosis. The treatment with SFN also suppressed the expression of multidrug resistance protein, reduced drug efflux, and increased anticancer activity of other antiproliferative agents including paclitaxel. A significant reduction in tumor volume was also observed by SFN in a subcutaneous tumor model of BEAC. Anticancer activity could be attributed to the induction of caspase 8 and p21 and down-regulation of hsp90, a molecular chaperon required for activity of several proliferation-associated proteins. CONCLUSIONS: These data indicate that a natural product with antioxidant properties from broccoli has great potential to be used in chemoprevention and treatment of BEAC.  相似文献   
95.
The DNA methylation pattern in spermatozoa of buffalo bulls of different fertility status was investigated. Spermatozoa isolated DNA from two groups of buffalo bulls (n = 5), selected based on their artificial insemination–generated conception rate data followed by IVF efficiency, were studied for global methylation changes using a custom-designed 180 K buffalo (Bubalus bubalis) CpG island/promoter microarray. A total of 96 individual genes with another 55 genes covered under CpG islands were found differentially methylated in sperm of high-fertile and subfertile buffalo bulls. Important genes associated with biological processes, cellular components, and functions were identified to be differentially methylated in buffalo bulls with differential fertility status. The identified differentially methylated genes were found to be involved in germ cell development, spermatogenesis, capacitation, and embryonic development. The observations hint that methylation defects of sperm DNA may play a crucial role in determining the fertility of breeding bulls. This growing field of sperm epigenetics will be of great benefit in understanding the graded fertility conditions of breeding bulls in commercial livestock production system.  相似文献   
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Hypoplastic left heart syndrome(HLHS) refers to the abnormal development of the left-sided cardiac structures, resulting in obstruction to blood flow from the left ventricular outflow tract. In addition, the syndrome includes underdevelopment of the left ventricle, aorta, and aortic arch, as well as mitral atresia or stenosis. HLHS has been reported to occur in approximately 0.016 to 0.036% of all live births. Newborn infants with the condition generally are born at full term and initially appear healthy. As the arterial duct closes, the systemic perfusion becomes decreased, resulting in hypoxemia, acidosis, and shock. Usually, no heart murmur, or a non-specific heart murmur, may be detected. The second heart sound is loud and single because of aortic atresia. Often the liver is enlarged secondary to congestive heart failure. The embryologic cause of the disease, as in the case of most congenital cardiac defects, is not fully known. The most useful diagnostic modality is the echocardiogram. The syndrome can be diagnosed by fetal echocardiography between 18 and 22 weeks of gestation. Differential diagnosis includes other left-sided obstructive lesions where the systemic circulation is dependent on ductal flow (critical aortic stenosis, coarctation of the aorta, interrupted aortic arch). Children with the syndrome require surgery as neonates, as they have duct-dependent systemic circulation. Currently, there are two major modalities, primary cardiac transplantation or a series of staged functionally univentricular palliations. The treatment chosen is dependent on the preference of the institution, its experience, and also preference. Although survival following initial surgical intervention has improved significantly over the last 20 years, significant mortality and morbidity are present for both surgical strategies. As a result pediatric cardiologists continue to be challenged by discussions with families regarding initial decision relative to treatment, and long-term prognosis as information on long-term survival and quality of life for those born with the syndrome is limited.  相似文献   
100.
1 The composition of pome fruit orchard inhabiting spider assemblages was investigated at different geographical scales (Holarctic, European, inter- and intraregional levels within Hungary) using previous faunistic studies and data collected in Hungary between 1995 and 1997. Samples in Hungary were taken from the canopy and herb layer of apple and pear orchards in five markedly different fruit-growing regions by beating and sweep-netting methods. 2 The composition of canopy spider assemblages of apple orchards was analysed for the Holartic region and found to be determined by latitude at family level, and by the main zoogoegraphical regions at genus level. At the European scale, both the genus and species composition changed along a north–south gradient. 3 A comparison among apple and pear orchards located in different regions in Hungary, showed that both foliage- and grass-dwelling spider assemblages varied considerably in species composition and dominance order. 4 Within the same region, both the foliage- and grass-dwelling spider assemblages showed moderate differences in apple and pear orchards submitted to different treatments. Although the assemblages of spiders inhabiting the canopy and the herbaceous layer can be unambiguously distinguished, some overlap still occurs. 5 We conclude that the composition of spider assemblages is basically determined by geographical location. Although both pesticide treatments and available prey densities can influence the population of spiders, such factors are of moderate importance when compared with the effect of regionality, even when considered at smaller scale. However, most members of the family Theridiidae and the large orb-weavers (Araneidae) decreased considerably in treated plots. Scale-specific differences are thus relevant in determining the composition of prey–predator systems in orchards, and should be taken into account when designing integrated pest management (IPM) programs for apple and pear orchards.  相似文献   
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