206 research outputs found
Colonic Paneth cell metaplasia is pre-neoplastic condition of colonic cancer or not?
BACKGROUND: The carcinogenesis of colorectal cancer has been accepted by a model for a cascade of genetic alterations, named the adenoma-carcinoma sequence. In order to elucidate the carcinogenesis of the colorectal cancer more clearly, the genetic abnormalies of the non-neoplastic mucosal epithelium of the colon and rectum should be investigated. It has been speculated that colonic Paneth cell metaplasia (PaM) is one of the pre-neoplastic mucosa of colonic cancer. Therefore, we studied the propria mucosa of the right colon with PaM from the standpoints of the frequency of the K-ras codon 12 mutations (K-ras), which is initial genetic abnormality in colorectal cancer, and the loss of heterozygosity of microsatellite markers (LOH-MS), which has a relationship to development of colorectal cancer. METHODS: Fifty-two regions with PaM histopathologically from 12 surgically resected right colon specimens were studied. DNA extraction of the colonic mucosa with PaM was obtained using a microdissection method, and the frequency of the K-ras of PaM was investigated by enriched polymerase chain reaction-enzyme linked mini-sequence assay, and the frequency of the LOH-MS (D2S123, D17S250 and D5S346) of PaM was examined by high resolution fluorescenced labeled PCR primers. RESULTS: K-ras mutation was detected in fifteen regions among 52 PaM (28.9%). All mutations were a single mutation and GGT changed to AGT in eleven and GAT in four. LOH-MS were detected in twenty-one regions among 52 PaM (40.4%) (D2S123: 35.4%, 17/48 regions, D17S250: 13.7%, 7/51 regions, and D5S346: 0%, 0/52 regions). No K-ras mutations and LOH-MS were detected in the controls (Colorectal mucosa with no PaM). CONCLUSIONS: Colonic mucosa with Paneth cell metaplasia may be one of the pre-neoplastic mucosa in the development of the colonic epithelial neoplasia
Long-term stability of ubiquinol-10 in natural miso without artificial antioxidants
Ubiquinol-10, the reduced form of coenzyme Q10, has higher bioavailability but lower stability than ubiquinone-10, the oxidized form of coenzyme Q10. During the development of ubiquinol-fortified foods, ensuring a long shelf life of the ubiquinol content without sacrificing the flavor of the food is crucial. In this study, we determined the stability of ubiquinol-10 in natural miso, a fermented food made from soybean, salt, and koji, matured at 20–25 °C and stored in a refrigerator for up to three months. Three types of natural miso were developed, differing in their composition and the duration of maturation, using three different forms of ubiquinol-10: raw powder, stabilized powder, and stabilized granules. The ratio of ubiquinol-10 to total coenzyme Q10 was more than 90% during the maturation and storage of natural miso under standard conditions, regardless of the ubiquinol form and type of natural miso. Contrary to expectations, the ubiquinol-10 ratio in a more pigmented natural miso seemed to increase during the maturation period, one month after preparation, when an unstabilized bulk ubiquinol powder was used. These results suggest that naturally occurring antioxidants, which are constituents of miso ingredients and are produced during the maturation process of natural miso, could maintain the reduced state of ubiquinol-10, without the addition of artificial antioxidants or the preservation of anaerobic conditions
Establishment and Characterization of a Human Cell Line Derived from a Squamous Cell Carcinoma of the Tongue
A cell line designated as OSC-19 was established from the metastatic tumor which was found in a cervical lymph node of a male patient suffering squamous cell carcinoma (SCC) of tongue. OSC-19 cells were polygonal in shape and grew in a cobblestone pattern. Desmosomes and microvilli were observed by electron microscopic examination, but tonofilament bundles were scarce. However, immunofluorescence studies showed cytokeratins in the cytoplasms of OSC-19 cells. When inoculated into nude mice, OSC-19 cells had many distinctive desmosomes and plenty of tonofilament bundles. These observations suggested strongly that OSC-19 cell line was SCC in origin. OSC-19 cells had receptors of epidermal growth factor (EGF), but the growth of the cells in dish culture was inhibited by 1 to 100 ng/ml EGF in dose-dependent manners. OSC-19 cells could not grow in soft agar, suggesting that they were strongly anchorage dependent. However, in contrast to dish culture, EGF stimulated colony formation of OSC-19 cells in soft agar. These results suggested that EGF has complex effects on the cell growth
The Second Survey of the Molecular Clouds in the Large Magellanic Cloud by NANTEN. II. Star Formation
We studied star formation activities in the molecular clouds in the Large
Magellanic Cloud. We have utilized the second catalog of 272 molecular clouds
obtained by NANTEN to compare the cloud distribution with signatures of massive
star formation including stellar clusters, and optical and radio HII regions.
We find that the molecular clouds are classified into three types according to
the activities of massive star formation; Type I shows no signature of massive
star formation, Type II is associated with relatively small HII region(s) and
Type III with both HII region(s) and young stellar cluster(s). The radio
continuum sources were used to confirm that Type I GMCs do not host optically
hidden HII regions. These signatures of massive star formation show a good
spatial correlation with the molecular clouds in a sense they are located
within ~100 pc of the molecular clouds. Among possible ideas to explain the GMC
Types, we favor that the Types indicate an evolutionary sequence; i.e., the
youngest phase is Type I, followed by Type II and the last phase is Type III,
where the most active star formation takes place leading to cloud dispersal.
The number of the three types of GMCs should be proportional to the time scale
of each evolutionary stage if a steady state of massive star and cluster
formation is a good approximation. By adopting the time scale of the youngest
stellar clusters, 10 Myrs, we roughly estimate the timescales of Types I, II
and III to be 6 Myrs, 13 Myrs and 7 Myrs, respectively, corresponding to a
lifetime of 20-30 Myrs for the GMCs with a mass above the completeness limit, 5
x 10^4 Msun.Comment: accepted to the Astrophysical Journal Supplement Series. 20 figures
and 4 tables. Higher resolution color PDF is found at
http://www.a.phys.nagoya-u.ac.jp/~kawamura/research/NANTEN_LMC_2_preprint.pdf
(47 pages,32MB
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