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101.
A recurrent mutation in type II collagen gene causes Legg-Calvé-Perthes disease in a Japanese family
Miyamoto Y Matsuda T Kitoh H Haga N Ohashi H Nishimura G Ikegawa S 《Human genetics》2007,121(5):625-629
Legg-Calvé-Perthes disease (LCPD) is a common childhood hip disorder characterized by sequential stages of involvement of
the capital femoral epiphyses, including subchondral fracture, fragmentation, re-ossification and healing with residual deformity.
Most cases are sporadic, but familial cases have been described, with some families having multiple affected members. Genetic
factors have been implicated in the etiology of LCPD, but the causal gene has not been identified. We have located a missense
mutation (p.G1170S) in the type II collagen gene (COL2A1) in a Japanese family with an autosomal dominant hip disorder manifesting as LCPD and showing considerable intra-familial
phenotypic variation. This is the first report of a mutation in hereditary LCPD. COL2A1 mutations may be more common in LCPD patients than currently thought, particularly in familial and/or bilateral cases. 相似文献
102.
Hiroyoshi Hoshi Yuji Takagi Keizo Kobayashi Masakazu Onodera Taneaki Oikawa 《In vitro cellular & developmental biology. Animal》1991,27(7):578-584
Summary We have developed an improved serum-free medium to optimize the cell growth of bovine granulosa cells. The cells on collagen-coated
culture plates proliferated extensively in a nutrient medium supplemented with insulin, heparin binding growth factor-2 (HBGF-2),
lipoprotein, and bovine serum albumin (BSA). The cell doubling time at logarithmic phase and final cell density at confluent
cultures were equal to those of cultures grown in the presence of medium supplemented with optimal concentration (10%) of
fetal bovine serum (FBS). Whereas HBGF-2 or insulin alone had a small mitogenic effect of granulosa cells, lipoprotein or
BSA did not. When lipoprotein, BSA, or insulin was added together with HBGF-2, synergistic cell proliferation was observed
in all combinations. Insulin or lipoprotein had an additive mitogenic stimulation of these cells in the presence of BSA. After
granulosa cells were subcultivated in a serum-containing medium until three generations [8.5 cumulative population doubling
level (CPDL)], subsequent subcultivation of the cells in a complete serum-free medium could be achieved up to six generations
(14.4 CPDL). These results demonstrate that this serum-free medium can support the optimal cell growth and long-term subcultivation
of bovine granulosa cells. 相似文献
103.
Norio Ohashi Yoko Koyama Hiroshi Urakami Masahiro Fukuhara Akira Tamura Fumihiko Kawamori Seigo Yamamoto Shiro Kasuya Kentaro Yoshimura 《Microbiology and immunology》1996,40(9):627-638
A total of 40 strains of Orientia tsutsugamushi (34 isolates from patients and trombiculid mites in Japan, and 6 prototype strains of antigenic variants) were examined for classification based on the reactivities with type-specific monoclonal antibodies in indirect immunofluorescence tests, and on the restriction fragment length polymorphism of a polymerase chain reaction (PCR)-amplified 56-kilodalton type-specific antigenic protein gene. By these methods, several antigenic and genotypic variants were found among the strains, and these variants were classified into types and further into subtypes. These results suggest that there are many variants in O. tsutsugamushi, and the methods used here seem to be useful for the systematic classification of the numerous variants. A strain which may be a new type distinguishable from those identified previously was also found in this study. Furthermore, variety in the degree of pathogenicity in mice related to type and/or subtype classification were observed. 相似文献
104.
Fluence-response relationships were examined for positive and negative phototropism induced by blue (450 nm) and ultraviolet-B (UV-B, 280 nm) light, respectively, in the Pilobolus crystallinus sporangiophore. Fluence-response curves for both blue and UV-B light obtained by changing the fluence by varying exposure time only showed the classical first and second positive bending. However, fluence-response curves obtained by varying the fluence rate were bell-shaped irrespective of the length of the exposure time. With increasing exposure time the peak became higher along the ascendant arm and the descendant arm was shifted toward the higher fluence. The Bunsen-Roscoe reciprocity law was valid only when the fluence was less than approx. 400 pmol·m-2 for both blue and UV-B light. Because the shapes of the fluence-response curves for blue and UV-B light were nearly the same, the photoreceptor systems for both blue and UV-B light are considered to be the same.Abbreviation UV-B
ultraviolet-B 相似文献
105.
Aoyagi N Ohashi K Tomono S Yamamoto Y 《American journal of physiology. Heart and circulatory physiology》2000,278(4):H1035-H1041
A newly developed, very long-term ( approximately 7 days) ambulatory monitoring system for assessing beat-to-beat heart rate variability (HRV) and body movements (BM) was used to study the mechanism(s) responsible for the long-period oscillation in human HRV. Data continuously collected from five healthy subjects were analyzed by 1) standard auto- and cross-spectral techniques, 2) a cross-Wigner distribution (WD; a time-frequency analysis) between BM and HRV for 10-s averaged data, and 3) coarse-graining spectral analysis for 600 successive cardiac cycles. The results showed 1) a clear circadian rhythm in HRV and BM, 2) a 1/f (beta)-type spectrum in HRV and BM at ultradian frequencies, and 3) coherent relationships between BM and HRV only at specific ultradian as well as circadian frequencies, indicated by significant (P < 0.05) levels of the squared coherence and temporal localizations of the covariance between BM and HRV in the cross-WD. In a single subject, an instance in which the behavioral (mean BM) and autonomic [HRV power >0.15 Hz and mean heart rate (HR)] rhythmicities were dissociated occurred when the individual had an irregular daily life. It was concluded that the long-term HRV in normal humans contained persistent oscillations synchronized with those of BM at ultradian frequencies but could not be explained exclusively by activity levels of the subjects. 相似文献
106.
Unique requirements for template primers of DNA polymerase beta from rat ascites hepatoma AH130 cells. 下载免费PDF全文
K Ono A Ohashi K Tanabe A Matsukage M Nishizawa T Takahashi 《Nucleic acids research》1979,7(3):715-726
The optimal condition for the rat DNA polymerase beta activity with (rA)n . (dT)12-18 as a template-primer was determined. The activity was remarkably affected by the concentration of the primer, (dT)12-18' and the mixing ratio of (dT)12-18 to (rA)n. DNA polymerase beta requires higher primer concentration (Km = 11.1 microM with respect to 3'-OH of the primer) than DNA polymerase gamma (Km = 0.04 microM) or oncornaviral DNA polymerase (Km = 0.08 microM) and the enzyme represented the maximum activity in the base ratio of 2:1 with (dT)12-18 and (rA)n suggesting the difference in reaction mechanisms of these enzymes. Under the optimized conditions, the specific activity of the near homogeneous preparation of DNA polymerase beta was 1,000,000 units per mg protein. 相似文献
107.
The low molecular weight carbohydrate compositions of the seeds of 29 species ofVicia, namelyV. amoena, V. amurensis, V. bifolia, V. dumetorum, V. fauriei, V. japonica, V. nipponica, V. pisiformis, V. pseudo-orobus,
V. sylvatica, V. unijuga, V. venosa, V. cassubica, V. orobus, V. cracca agg.,V. hirsuta, V. villosa agg.,V. tetrasperma,V. oroboides, V. sepium, V. cuspidata, V. grandiflora, V. lathyloides, V. sativa agg.,V. bithynica, V. faba, V. narbonensis, V. hybrida andV. lutea were determined by gas liquid chromatography. The carbohydrate compositions were found to be species-specific. Principal
component analysis of the carbohydrate composition data showed that these species can be divided into three groups. Although,
as far as the examined species were concerned, these groups were not correlated with the known subgenera, significant correlation
between the groups and the known sections was detected in the subgenusVicia. The carbohydrate composition character would be important to clarify the relationships among closely related taxa of the
genusVicia. 相似文献
108.
109.
Masao Ohashi Takuji Oyama Endy Widya Putranto Tsuyoshi Waku Hiromi Nobusada Ken Kataoka Kenji Matsuno Masakazu Yashiro Kosuke Morikawa Nam-ho Huh Hiroyuki Miyachi 《Bioorganic & medicinal chemistry》2013,21(8):2319-2332
In the continuing study directed toward the development of peroxisome proliferator-activated receptor gamma (hPPARγ) agonist, we attempted to improve the water solubility of our previously developed hPPARγ-selective agonist 3, which is insufficiently soluble for practical use, by employing two strategies: introducing substituents to reduce its molecular planarity and decreasing its hydrophobicity via replacement of the adamantyl group with a heteroaromatic ring. The first approach proved ineffective, but the second was productive. Here, we report the design and synthesis of a series of α-benzyl phenylpropanoic acid-type hPPARγ partial agonists with improved aqueous solubility. Among them, we selected (R)-7j, which activates hPPARγ to the extent of about 65% of the maximum observed with a full agonist, for further evaluation. The ligand-binding mode and the reason for the partial-agonistic activity are discussed based on X-ray-determined structure of the complex of hPPARγ ligand-binding domain (LBD) and (R)-7j with previously reported ligand-LDB structures. Preliminal apoptotic effect of (R)-7j against human scirrhous gastric cancer cell line OCUM-2MD3 is also described. 相似文献
110.
Although maternal or uniparental inheritance of mitochondrial genomes is a general rule, biparental inheritance is sometimes
observed in protists and fungi, including yeasts. In yeast, recombination occurs between the mitochondrial genomes inherited
from both parents. Mitochondrial fusion observed in yeast zygotes is thought to set up a space for DNA recombination. In the
last decade, a universal mitochondrial fusion mechanism has been uncovered, using yeast as a model. On the other hand, an
alternative mitochondrial fusion mechanism has been identified in the true slime mold Physarum polycephalum. A specific mitochondrial plasmid, mF, has been detected as the genetic material that causes mitochondrial fusion in P. polycephalum. Without mF, fusion of the mitochondria is not observed throughout the life cycle, suggesting that Physarum has no constitutive mitochondrial fusion mechanism. Conversely, mitochondria fuse in zygotes and during sporulation with
mF. The complete mF sequence suggests that one gene, ORF640, encodes a fusogen for Physarum mitochondria. Although in general, mitochondria are inherited uniparentally, biparental inheritance occurs with specific
sexual crossing in P. polycephalum. An analysis of the transmission of mitochondrial genomes has shown that recombinations between two parental mitochondrial
genomes require mitochondrial fusion, mediated by mF. Physarum is a unique organism for studying mitochondrial fusion. 相似文献