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121.
We evaluated age-related changes in serum osteocalcin concentrations in non-periparturient cows and variations in serum osteocalcin concentration in periparturient primiparous and multiparous cows. The serum osteocalcin levels were evaluated in 144 non-periparturient Holstein dairy cows aged 11 days to 10 years; these levels were the highest in the youngest cows, appeared to steadily decrease with age until the time of the first calving, and were subsequently maintained at low levels. Between 14 days before calving and 21 days after calving, the serum osteocalcin levels were significantly higher in the primiparous cows than in the multiparous cows. A comparison between age-matched non-periparturient and periparturient cows showed that serum osteocalcin levels were significantly lowered during late gestation in both primiparous and multiparous cows. These results suggest that serum osteocalcin measurement might be useful for the detection of mineral imbalances at the time of parturition in cows.  相似文献   
122.
Chondrosarcoma is a malignant primary bone tumor that is resistant to chemotherapy and radiation therapy. α-Mangostin, a component of Garcinia mangostana Linn, is a xanthone derivative shown to have antioxidant and antitumor properties. This study is the first to investigate anticancer effects of α-mangostin in the human chondrosarcoma cell line SW1353. We showed that α-mangostin inhibited cell proliferation of SW1353 cells in a time- and dose-dependent manner by using the trypan blue exclusion method. Hoechst 33342 nuclear staining and nucleosomal DNA-gel electrophoresis revealed that α-mangostin could induce nuclear condensation and fragmentation, typically seen in apoptosis. Flow cytometry using Annexin V/PI double staining assessed apoptosis, necrosis and viability. α-Mangostin activated caspase-3, -8, -9 expression, decreased Bcl-2 and increased Bax. This promotes mitochondrial dysfunction, leading to the release of cytochrome c from the mitochondria to the cytoplasm. In addition, total and phosphorylated ERK and JNK were downregulated in α-mangostin-treated SW1353 cells but no changes in p38. α-Mangostin also decreased phosphorylated Akt without altering total Akt. These results suggest that α-mangostin inhinbited cell proliferation and induced apoptosis through downregulation of ERK, JNK and Akt signaling pathway in human chondrosarcoma SW1353 cells.  相似文献   
123.
We previously demonstrated that esculeogenin A, a new aglycone of the tomato sapogenol esculeoside A, inhibits both acyl coenzyme A:cholesterol acyl-transferase (ACAT)-1 and -2 and ameliorates the pathogenesis of atherosclerosis in apoE deficient mice. Although we believe that daily intake of esculeoside A from tomato products can play a beneficial role in preventing the pathogenesis of atherosclerosis, the compound is not being used for preventive medicine due to the lack of information on methods for quantitative analysis and the content and stability of the compound in tomato products. In the present study, we report the development of a high-performance liquid chromatography (HPLC) method using an instrument equipped with a refractive index (RI) detector for esculeoside A quantification. We used this method to measure the changes in esculeoside A content during maturation, its distribution in the fruit body, and its stability during the heating process. The contents of esculeoside A in cherry tomatoes and Momotaro tomatoes were 21- and 9-fold, respectively, higher than that of lycopene, which is the most well-known compound in tomatoes. Furthermore, the esculeoside A content in pericarp wall was higher than in the whole tomato fruit and increased in a time-dependent manner during maturation. Although the melting point of purified esculeoside A was 225 °C, the esculeoside A in crude tomato extract decreased in a temperature-dependent manner. Degradation due to the heating process was inhibited under a pH of 9. These results demonstrated that the esculeoside A content differs in the various types of tomatoes, during maturation, and during the heating process used for preservation.  相似文献   
124.
The storage proteins of the pili nut (Canarium ovatum, Engl.), quantitatively extracted using the modified Osborne protein fractionationscheme, revealed that the salt-soluble globulin was the main storage proteinwithin the kernel (i.e., >>60.3%). Further physicochemicalcharacterization of this aqueous soluble globulin revealed that it existed in an11S like form and was composed of two main subunits of 22,600 and31,600 Da. These subunits were found to be disulfide-linked (in a 1:1ratio) forming intermediary subunits (i.e., dimers) with a molecular weightof approximately 52,600 Da. The overall molecular weight of the 11Sglobulin was determined to be approximately 300,000 Da suggesting thatthe globulin possessed a dodecameric-like structure of 6 dimers for a totalof 12 subunits. Using differential scanning microcalorimetry, thedenaturation temperature of the globulin was shown to occur at89.3 °C. Overall, the pili nut 11S globulin was found to possessmany similar physicochemical properties to those of other 11S oilseedglobulins.  相似文献   
125.
The Japanese Crested Ibis Nipponia nippon is a critically threatened bird. The post‐hatch eggs of the current captive population of this species on Sado Island have been stored at room temperature for the long‐term. In this study, we investigated the suitability of the vascularized chorioallantois membrane from the eggs as a non‐invasive DNA source. Using microsatellite loci developed for the Japanese Crested Ibis, we performed three experiments for comparison of genotypes obtained among DNA. First, DNA from five different sites of the identical membrane showed the same genotypes at either of two loci examined. Second, DNA from the membrane of each full‐sibling birds and blood of their parents showed the genotypes that were consistent with Mendelian parent–offspring relationships at any of eight loci examined. Third, DNA from the membrane and blood of the same bird showed the matched genotypes at any of eight loci examined. These results indicate that the vascularized chorioallantois membrane from post‐hatch eggs stored at room temperature for the long‐ term can be used as a reliable DNA source of offspring that had hatched from the egg. This study will promote a molecular genetics study on genetic diversity of the current captive Japanese Crested Ibis population on Sado Island.  相似文献   
126.
The purpose of this study is to compare feeding and other behavior and nutrient digestibility of tropical grade Brahman (body weight (BW) = 231 kg ± 12.4; n = 3) and crossbred water buffalo (BW = 300 kg ± 13.9; n = 3). This experiment on digestibility and measures of muscles of mastication utilized one‐way, and animal behavior two‐way, analysis of variance, respectively. Two video camcorders were installed in each pair of buffalo and Brahman for 24 h period programmed on the 107th, 109th and 111th days of the digestion trials. Frequency and duration of feeding, meal intake, rumination, bolus, chews, drinking, defecating, standing and lying were recorded daily. Muscle diameter of Digastricus, Masseter and Pterygoid and different regions of the tongue were sampled and measured under light microscope using a standard micrometer. Buffalo obtained significantly higher intake of dry matter, roughage, crude protein, total digestible nutrient and metabolized energy than Brahman. This was supported by longer meal duration (P ≤ 0.05), and shorter meal breaks (P ≤ 0.05) of buffalo than Brahman. The diameter of the muscles for mastication was bigger (P ≤ 0.05) in buffalo than in Brahman, which is indicative of stronger chewing ability. Briefly, lesser and slower chewing action; higher intake of roughage and crude protein; and longer resting behavior of crossbred water buffalo than Brahman are all indicative of better digestive and metabolic performance of the buffalo under high roughage feeding conditions.  相似文献   
127.
Fecal DNA analysis is a useful tool for the investigation of endangered species. Tamaraw (Bubalus mindorensis) is endemic to the Philippine island of Mindoro but knowledge of its genetic and ecological information is limited. In this study, we developed a species identification method for tamaraw by fecal DNA analysis. Eighteen feces presumed to be from tamaraw were collected in Mount Iglit‐Baco National Park and species‐known feces from domestic buffaloes and cattle were obtained from a farm. Additionally, one species‐unknown fecal sample was obtained in Mount Aruyan Preserve, where the sighting of tamaraw has not been reported in recent years. Based on DNA sequence data previously reported, the genus Bubalus‐ and tamaraw‐specific primers for PCR of cytochrome b gene were newly designed. The Bubalus‐specific primer yielded a 976 bp fragment of cytochrome b for all fecal samples from tamaraw and domestic buffaloes, but not for cattle, whereas the tamaraw‐specific primer yielded a 582 bp fragment for all tamaraw fecal samples and for one of the four domestic buffalo samples. PCR‐RFLP (restriction fragment length polymorphism) analysis of the 976 bp PCR fragment with AvrII or BsaXI provided distinct differences between tamaraw and domestic buffalo. PCR‐RFLP analysis also showed that the species‐unknown sample obtained in Mount Aruyan Preserve, originates from tamaraw.  相似文献   
128.
Endosperm texture is an important factor governing the end-product quality of cereals. The texture of wheat (Triticum aestivum L.) endosperm is controlled by puroindoline a and b genes which are both absent in rice (Oryza sativa L.). It has been reported that the endosperm texture of rice can be modified by puroindoline genes. The mechanism, however, by which puroindolines affect the ultrastructure of rice endosperm cells remains to be investigated. In this study, we observed the ultrastructure of endosperm cells and the morphology of isolated starch granules of the transgenic rice expressing the puroindoline b gene. SEM and TEM observations indicated that compound starch granules were embedded within the matrix material in non-transgenic rice, Nipponbare, whereas they were surrounded by spaces in the transgenic rice. The morphology and size of each starch granule were not different between non-transgenic and the transgenic rice. However, the transgenic rice flour showed smaller particle size, higher starch damage, and lower viscosity during gelatinization than that of non-transgenic rice. These results confirm that puroindoline b reduces the grain hardness in rice. Moreover, the results also suggest that puroindoline b functions at the surface of compound starch granules, and not on polygonal starch granules in rice endosperm.  相似文献   
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130.
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