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91.
John E. Moore Yasunori Maeda Jiru Xu B. Cherie Millar Peter H. Herold V. M. J. Browne-Lauwers Colin E. Goldsmith Anne Loughrey Paul J. Rooney J. Stuart Elborn Motoo Matsuda 《World journal of microbiology & biotechnology》2008,24(7):1227-1232
To employ 16S rDNA PCR and automated sequencing techniques to identify a collection of bacterial veterinary pathogens from
avian, equine, canine and ovine sources, that have proven difficult to identify, employing conventional cultural techniques.
Universal or “broad-range” eubacterial PCR was performed on a collection of 46 difficult-to-identify bacterial isolates originating
from clinical veterinary specimens. 16S rDNA PCR was performed using two sets of universal primers to successfully generate
a composite amplicon of 1,068 bp, which was sequenced to obtain each isolate’s identity. Sequence analysis was able to identify
all isolates examined with relative ease. Where the use of molecular identification methods is justified, such as in outbreak
control or bioterrorism in animal health, employment of partial 16S rDNA PCR and sequencing employing universal or “broad-range”
16S rDNA, provides a valuable and reliable method of identification of such pathogens. 相似文献
92.
Nakahara Y Watanabe M Fujita A Kanamori Y Tanaka D Iwata K Furuki T Sakurai M Kikawada T Okuda T 《Journal of insect physiology》2008,54(8):1220-1225
Strategies to combat desiccation are critical for organisms living in arid and semi-arid areas. Larvae of the Australian chironomid Paraborniella tonnoiri resist desiccation by reducing water loss. In contrast, larvae of the African species Polypedilum vanderplanki can withstand almost complete dehydration, referred to as anhydrobiosis. For successful anhydrobiosis, the dehydration rate of P. vanderplanki larvae has to be controlled. Here, we desiccated larvae by exposing them to different drying regimes, each progressing from high to low relative humidity, and examined survival after rehydration. In larvae of P. vanderplanki, reactions following desiccation can be categorized as follows: (I) no recovery at all (direct death), (II) dying by unrepairable damages after rehydration (delayed death), and (III) full recovery (successful anhydrobiosis). Initial conditions of desiccation severely affected survival following rehydration, i.e. P. vanderplanki preferred 100% relative humidity where body water content decreased slightly. In subsequent conditions, unfavorable dehydration rate, such as more than 0.7 mg water lost per day, resulted in markedly decreased survival rate of rehydrated larvae. Slow dehydration may be required for the synthesis and distribution of essential molecules for anhydrobiosis. Larvae desiccated at or above maximum tolerable rates sometimes showed temporary recovery but died soon after. 相似文献
93.
Matsuda Yoshihiro; Uzaki Tomoya; Iwasawa Norio; Tanaka Takaharu; Saito Tatsuaki 《Plant & cell physiology》1990,31(5):717-720
A cell wall lytic enzyme (gamete wall-autolysin) from Chlamydomonasreinhardtii specifically cleaved several synthetic model peptides,-neo-endorphin, dynorphin (113), neurotensin and mastoparan,at the peptide bonds between consecutive hydrophobic amino-acidresidues. The cleavage was not significantly affected by high-saltconditions which are known to inhibit digestion of the cellwall. (Received December 14, 1989; Accepted April 5, 1990) 相似文献
94.
Reiji Kojima Tatsukuni Ohno Motoyasu Iikura Toshiro Niki Mitsuomi Hirashima Keichi Iwaya Hitoshi Tsuda Shigeaki Nonoyama Akio Matsuda Hirohisa Saito Kenji Matsumoto Susumu Nakae 《PloS one》2014,9(1)
Galectin-9 (Gal-9), a lectin having a β-galactoside-binding domain, can induce apoptosis of Th1 cells by binding to TIM-3. In addition, Gal-9 inhibits IgE/Ag-mediated degranulation of mast cell/basophilic cell lines by binding to IgE, thus blocking IgE/Ag complex formation. However, the role of Gal-9 in mast cell function in the absence of IgE is not fully understood. Here, we found that recombinant Gal-9 directly induced phosphorylation of Erk1/2 but not p38 MAPK in a human mast cell line, HMC-1, which does not express FcεRI. Gal-9 induced apoptosis and inhibited PMA/ionomycin-mediated degranulation of HMC-1 cells. On the other hand, Gal-9 induced cytokine and/or chemokine production by HMC-1 cells, dependent on activation of ERK1/2 but not p38 MAPK. In addition, the lectin activity of Gal-9 was required for Gal-9-mediated cytokine secretion by HMC-1 cells. These observations suggest that Gal-9 has dual properties as both a regulator and an activator of mast cells. 相似文献
95.
Fumiyuki Nakagawa Katsutaro Morino Satoshi Ugi Atsushi Ishikado Keiko Kondo Daisuke Sato Shiho Konno Ken-ichi Nemoto Chisato Kusunoki Osamu Sekine Akihiro Sunagawa Masanori Kawamura Noriko Inoue Yoshihiko Nishio Hiroshi Maegawa 《Biochemical and biophysical research communications》2014
It has recently been reported that expression of heme oxygenase-1 (HO-1) plays a protective role against many diseases. Furthermore, n-3 polyunsaturated fatty acids (PUFAs) were shown to induce HO-1 expression in several cells in vitro, and in a few cases also in vivo. However, very few reports have demonstrated that n-3 PUFAs induce HO-1 in vivo. 相似文献
96.
Yosuke Ichijima Ken-ichi Yoshioka Yoshiko Yoshioka Keitaro Shinohe Hiroaki Fujimori Junya Unno Masatoshi Takagi Hidemasa Goto Masaki Inagaki Shuki Mizutani Hirobumi Teraoka 《PloS one》2010,5(1)
During tumorigenesis, cells acquire immortality in association with the
development of genomic instability. However, it is still elusive how genomic
instability spontaneously generates during the process of tumorigenesis. Here,
we show that precancerous DNA lesions induced by oncogene acceleration, which
induce situations identical to the initial stages of cancer development, trigger
tetraploidy/aneuploidy generation in association with mitotic aberration.
Although oncogene acceleration primarily induces DNA replication stress and the
resulting lesions in the S phase, these lesions are carried over into the M
phase and cause cytokinesis failure and genomic instability. Unlike directly
induced DNA double-strand breaks, DNA replication stress-associated lesions are
cryptogenic and pass through cell-cycle checkpoints due to limited and
ineffective activation of checkpoint factors. Furthermore, since damaged M-phase
cells still progress in mitotic steps, these cells result in chromosomal
mis-segregation, cytokinesis failure and the resulting tetraploidy generation.
Thus, our results reveal a process of genomic instability generation triggered
by precancerous DNA replication stress. 相似文献
97.
Ken Horii Takashi Adachi Tetsuya Matsuda Tsutomu Tanaka Hiroshi Sahara Seiji Shibasaki Chiaki Ogino Yoji Hata Mitsuyoshi Ueda Akihiko Kondo 《Journal of Molecular Catalysis .B, Enzymatic》2009,59(4):297-301
β-Glucosidase (BGL1) from Aspergillus oryzae was efficiently produced in recombinant A. oryzae using sodM promoter-mediated expression system. The yield of BGL1 was 960 mg/l in liquid culture, which is 20-fold higher than the yield of BGL1 produced using the yeast Saccharomyces cerevisiae. Recombinant BGL1 converted isoflavone glycosides into isoflavone aglycones more efficiently than β-glucosidase from almond. In addition, BGL1 produced isoflavone aglycones even in the presence of the insoluble form of isoflavone glycosides. 相似文献
98.
Minoru Kawakami Masafumi Umeda Naomi Nakagata Toru Takeo Ken-ichi Yamamura 《BMC developmental biology》2011,11(1):1-17
Background
Heparan sulfate (HS) is present on the surface of virtually all mammalian cells and is a major component of the extracellular matrix (ECM), where it plays a pivotal role in cell-cell and cell-matrix cross-talk through its large interactome. Disruption of HS biosynthesis in mice results in neonatal death as a consequence of malformed lungs, indicating that HS is crucial for airway morphogenesis. Neonatal mortality (~50%) in newborns with congenital diaphragmatic hernia (CDH) is principally associated with lung hypoplasia and pulmonary hypertension. Given the importance of HS for lung morphogenesis, we investigated developmental changes in HS structure in normal and hypoplastic lungs using the nitrofen rat model of CDH and semi-synthetic bacteriophage ('phage) display antibodies, which identify distinct HS structures.Results
The pulmonary pattern of elaborated HS structures is developmentally regulated. For example, the HS4E4V epitope is highly expressed in sub-epithelial mesenchyme of E15.5 - E17.5 lungs and at a lower level in more distal mesenchyme. However, by E19.5, this epitope is expressed similarly throughout the lung mesenchyme. We also reveal abnormalities in HS fine structure and spatiotemporal distribution of HS epitopes in hypoplastic CDH lungs. These changes involve structures recognised by key growth factors, FGF2 and FGF9. For example, the EV3C3V epitope, which was abnormally distributed in the mesenchyme of hypoplastic lungs, is recognised by FGF2.Conclusions
The observed spatiotemporal changes in HS structure during normal lung development will likely reflect altered activities of many HS-binding proteins regulating lung morphogenesis. Abnormalities in HS structure and distribution in hypoplastic lungs can be expected to perturb HS:protein interactions, ECM microenvironments and crucial epithelial-mesenchyme communication, which may contribute to lung dysmorphogenesis. Indeed, a number of epitopes correlate with structures recognised by FGFs, suggesting a functional consequence of the observed changes in HS in these lungs. These results identify a novel, significant molecular defect in hypoplastic lungs and reveals HS as a potential contributor to hypoplastic lung development in CDH. Finally, these results afford the prospect that HS-mimetic therapeutics could repair defective signalling in hypoplastic lungs, improve lung growth, and reduce CDH mortality. 相似文献99.
A soluble enzyme preparation (20,000 X g supernatant fraction), prepared from the mycelia of wild-type Neurospora crassa, was capable of transferring [14C]glucose from UDP-[14C]glucose into both trichloroacetic acid (TCA)-soluble and TCA-insoluble macromolecule products in the absence of added primer. These reactions did not require either high concentrations of salts or any other chemical reagents. Two labeled products were formed; one was a glycogen-like polysaccharide and the other was a glycoprotein with glucosyl chains bound to protein through an acid-labile bond. After mild treatment of the glucoprotein with acid, the product liberated from the protein behaved as a mixture of malto-oligosaccharides and alpha-1,4-glucan with branches. The carbohydrate moiety of the glucoprotein seemed to be released upon prolonged incubation with the enzyme preparation. The glucan thus liberated from the glucoprotein may serve as a primer for the glycogen synthase. The results obtained are therefore suggestive of the existence of a glucoproteic intermediate in the initiation of glycogen biosynthesis. 相似文献
100.
Aoki N Ueno S Mano H Yamasaki S Shiota M Miyazaki H Yamaguchi-Aoki Y Matsuda T Ullrich A 《The Journal of biological chemistry》2004,279(11):10765-10775
PTP20, also known as HSCF/protein-tyrosine phosphatase K1/fetal liver phosphatase 1/brain-derived phosphatase 1, is a cytosolic protein-tyrosine phosphatase with currently unknown biological relevance. We have identified that the nonreceptor protein-tyrosine kinase Tec-phosphorylated PTP20 on tyrosines and co-immunoprecipitated with the phosphatase in a phosphotyrosine-dependent manner. The interaction between the two proteins involved the Tec SH2 domain and the C-terminal tyrosine residues Tyr-281, Tyr-303, Tyr-354, and Tyr-381 of PTP20, which were also necessary for tyrosine phosphorylation/dephosphorylation. Association between endogenous PTP20 and Tec was also tyrosine phosphorylation-dependent in the immature B cell line Ramos. Finally, the Tyr-281 residue of PTP20 was shown to be critical for deactivating Tec in Ramos cells upon B cell receptor ligation as well as dephosphorylation and deactivation of Tec and PTP20 itself in transfected COS7 cells. Taken together, PTP20 appears to play a negative role in Tec-mediated signaling, and Tec-PTP20 interaction might represent a negative feedback mechanism. 相似文献