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931.
Uchima CA Tokuda G Watanabe H Kitamoto K Arioka M 《Applied microbiology and biotechnology》2011,89(6):1761-1771
Neotermes koshunensis is a lower termite that secretes endogenous β-glucosidase in the salivary glands. This β-glucosidase (G1NkBG) was successfully
expressed in Aspergillus oryzae. G1NkBG was purified to homogeneity from the culture supernatant through ammonium sulfate precipitation and anion exchange,
hydrophobic, and gel filtration chromatographies with a 48-fold increase in purity. The molecular mass of the native enzyme
appeared as a single band at 60 kDa after gel filtration analysis, indicating that G1NkBG is a monomeric protein. Maximum
activity was observed at 50 °C with an optimum pH at 5.0. G1NkBG retained 80% of its maximum activity at temperatures up to
45 °C and lost its activity at temperatures above 55 °C. The enzyme was stable from pH 5.0 to 9.0. G1NkBG was most active
towards laminaribiose and p-nitrophenyl-β-d-fucopyranoside. Cellobiose, as well as cello-oligosaccharides, was also well hydrolyzed. The enzyme activity was slightly
stimulated by Mn2+ and glycerol. The K
m and V
max values were 0.77 mM and 16 U/mg, respectively, against p-nitrophenyl-β-d-glucopyranoside. An unusual finding was that G1NkBG was stimulated by 1.3-fold when glucose was present in the reaction mixture
at a concentration of 200 mM. These characteristics, particularly the stimulation of enzyme activity by glucose, make G1NkBG
of great interest for biotechnological applications, especially for bioethanol production. 相似文献
932.
Moriguchi R Ohata K Kanahama K Takahashi H Nishiyama M Kanayama Y 《Journal of plant physiology》2011,168(16):1927-1933
Tomato (Solanum lycopersicum L.) plants were transformed with an antisense construct of a cDNA encoding tomato telomere-binding protein (LeTBP1) to describe the role of a telomere-binding protein at the whole plant level. Fruit size decreased corresponding to the degree of suppression of LeTBP1 expression. This inhibition of fruit development was likely due to a decrease in the number of seeds in the LeTBP1 antisense plants. Pollen fertility and pollen germination rate decreased in accordance with the degree of suppression of LeTBP1 expression. Ovule viability was also reduced in the LeTBP1 antisense plants. Although plant height was somewhat reduced in the antisense plants compared to the control plants, the number and weight of leaves were unaffected by LeTBP1 suppression. The number and morphology of flowers were also normal in the antisense plants. These indicate that reduced fertility in the antisense plants is not an indirect effect of altered vegetative growth. LeTBP1 expression was sensitive to temperature stress in wild-type plants. We conclude that LeTBP1 plays a critical role in seed and fruit development rather than vegetative growth and flower formation. 相似文献
933.
Hirofumi Fujita Hanako Aoki Itsuki Ajioka Maya Yamazaki Manabu Abe Arata Oh-Nishi Kenji Sakimura Izumi Sugihara 《PloS one》2014,9(1)
Aldolase C (Aldoc, also known as “zebrin II”), a brain type isozyme of a glycolysis enzyme, is expressed heterogeneously in subpopulations of cerebellar Purkinje cells (PCs) that are arranged longitudinally in a complex striped pattern in the cerebellar cortex, a pattern which is closely related to the topography of input and output axonal projections. Here, we generated knock-in Aldoc-Venus mice in which Aldoc expression is visualized by expression of a fluorescent protein, Venus. Since there was no obvious phenotypes in general brain morphology and in the striped pattern of the cerebellum in mutants, we made detailed observation of Aldoc expression pattern in the nervous system by using Venus expression in Aldoc-Venus heterozygotes. High levels of Venus expression were observed in cerebellar PCs, cartwheel cells in the dorsal cochlear nucleus, sensory epithelium of the inner ear and in all major types of retinal cells, while moderate levels of Venus expression were observed in astrocytes and satellite cells in the dorsal root ganglion. The striped arrangement of PCs that express Venus to different degrees was carefully traced with serial section alignment analysis and mapped on the unfolded scheme of the entire cerebellar cortex to re-identify all individual Aldoc stripes. A longitudinally striped boundary of Aldoc expression was first identified in the mouse flocculus, and was correlated with the climbing fiber projection pattern and expression of another compartmental marker molecule, heat shock protein 25 (HSP25). As in the rat, the cerebellar nuclei were divided into the rostrodorsal negative and the caudoventral positive portions by distinct projections of Aldoc-positive and negative PC axons in the mouse. Identification of the cerebellar Aldoc stripes in this study, as indicated in sample coronal and horizontal sections as well as in sample surface photos of whole-mount preparations, can be referred to in future experiments. 相似文献
934.
935.
Manabu Kadoya Hidenori Koyama Akinori Kanzaki Masafumi Kurajoh Miki Hatayama Jun Shiraishi Hirokazu Okazaki Takuhito Shoji Yuji Moriwaki Tetsuya Yamamoto Masaaki Inaba Mitsuyoshi Namba 《PloS one》2014,9(8)
Context
Basic studies have shown that brain-derived neurotrophic factor (BDNF) has critical roles in the survival, growth, maintenance, and death of central and peripheral neurons, while it is also involved in regulation of the autonomic nervous system. Furthermore, recent clinical studies have suggested potential role of plasma BDNF in the circulatory system.Objective
We investigated the mutual relationships among plasma BDNF, patterns of nocturnal blood pressure changes (dippers, non-dippers, extra-dippers, and reverse-dippers), and cardiac autonomic function as determined by heart rate variability (HRV).Design
This was a cross-sectional study of patients registered in the Hyogo Sleep Cardio-Autonomic Atherosclerosis (HSCAA) Study from October 2010 to November 2012.Patients
Two-hundred fifty patients with 1 or more cardiovascular risk factor(s) (obesity, smoking, presence of cardiovascular event history, hypertension, dyslipidemia, diabetes mellitus, chronic kidney disease) were enrolled.Results
Plasma BDNF levels (natural logarithm transformed) were significantly (p = 0.001) lower in reverse-dipper patients (7.18±0.69 pg/ml, mean ± SD, n = 36) as compared to dippers (7.86±0.86 pg/ml, n = 100). Multiple logistic regression analysis showed that BDNF (odds ratios: 0.417, 95% confidence interval: 0.228–0.762, P = 0.004) was the sole factor significantly and independently associated with the reverse-dippers as compared with dippers. Furthermore, plasma BDNF level was significantly and positively correlated with the time-domain (SDNN, SDANN5, CVRR) and frequency-domain (LF) of HRV parameters. Finally, multiple logistic regression analyses showed that the relationship between plasma BDNF and the reverse-dippers was weakened, yet remained significant or borderline significant even after adjusting for HRV parameters.Conclusions
Low plasma BDNF was independently associated with patients showing a reverse-dipper pattern of nocturnal blood pressure, in which an imbalance of cardiac autonomic function may be partly involved. 相似文献936.
Honoka Kiso Katsu Takahashi Kazuyuki Saito Yumiko Togo Hiroko Tsukamoto Boyen Huang Manabu Sugai Akira Shimizu Yasuhiko Tabata Aris N. Economides Harold C. Slavkin Kazuhisa Bessho 《PloS one》2014,9(5)
Bone morphogenetic proteins (BMPs) are highly conserved signaling molecules that are part of the transforming growth factor (TGF)-beta superfamily, and function in the patterning and morphogenesis of many organs including development of the dentition. The functions of the BMPs are controlled by certain classes of molecules that are recognized as BMP antagonists that inhibit BMP binding to their cognate receptors. In this study we tested the hypothesis that USAG-1 (uterine sensitization-associated gene-1) suppresses deciduous incisors by inhibition of BMP-7 function. We learned that USAG-1 and BMP-7 were expressed within odontogenic epithelium as well as mesenchyme during the late bud and early cap stages of tooth development. USAG-1 is a BMP antagonist, and also modulates Wnt signaling. USAG-1 abrogation rescued apoptotic elimination of odontogenic mesenchymal cells. BMP signaling in the rudimentary maxillary incisor, assessed by expressions of Msx1 and Dlx2 and the phosphorylation of Smad protein, was significantly enhanced. Using explant culture and subsequent subrenal capsule transplantation of E15 USAG-1 mutant maxillary incisor tooth primordia supplemented with BMP-7 demonstrated in USAG-1+/− as well as USAG-1−/− rescue and supernumerary tooth development. Based upon these results, we conclude that USAG-1 functions as an antagonist of BMP-7 in this model system. These results further suggest that the phenotypes of USAG-1 and BMP-7 mutant mice reported provide opportunities for regenerative medicine and dentistry. 相似文献
937.
Kuniaki Kiuchi Soichiro Kitamura Toshiaki Taoka Fumihiko Yasuno Masami Tanimura Kiwamu Matsuoka Daisuke Ikawa Michihiro Toritsuka Kazumichi Hashimoto Manabu Makinodan Jun Kosaka Masayuki Morikawa Kimihiko Kichikawa Toshifumi Kishimoto 《PloS one》2014,9(8)
Subjective cognitive impairment may be a very early at-risk period of the continuum of dementia. However, it is difficult to discriminate at-risk states from normal aging. Thus, detection of the early pathological changes in the subjective cognitive impairment period is needed. To elucidate these changes, we employed diffusion tensor imaging and volumetry analysis, and compared subjective cognitive impairment with normal, mild cognitive impairment and Alzheimer''s disease. The subjects in this study were 39 Alzheimer''s disease, 43 mild cognitive impairment, 28 subjective cognitive impairment and 41 normal controls. There were no statistically significant differences between the normal control and subjective cognitive impairment groups in all measures. Alzheimer''s disease and mild cognitive impairment had the same extent of brain atrophy and diffusion changes. These results are consistent with the hypothetical model of the dynamic biomarkers of Alzheimer''s disease. 相似文献
938.
Roudkenar MH Halabian R Bahmani P Roushandeh AM Kuwahara Y Fukumoto M 《Free radical research》2011,45(7):810-819
Neutrophil Gelatinase-Associated Lipocalin (NGAL/Lcn2), a member of the lipocalin family, has a variety of functions. There are extensive studies examining the expression of NGAL under harmful conditions. However, its precise function remains poorly understood. Heme Oxygenase 1 (HO-1) is an enzyme with well-established cytoprotective effects. Previous work showed that NGAL induces expression of HO-1. Interestingly, the same stimuli induced the expression of both NGAL and HO-1. The current study was designed to (1) determine whether NGAL exerts its cytoprotective effect through HO-1 and (2) compare NGAL and HO-1 with each other in terms of their protective role against oxidative stress. The current data indicate that NGAL exerts its cytoprotective effect independent of HO-1 and protects cells against oxidative stress more efficiently than HO-1. The data also strongly suggest that induction of NGAL under harmful conditions is a compensatory response to ameliorate oxidative stress-mediated toxicity. These findings may suggest new applications of NGAL, particularly when oxidative stress is a major factor. 相似文献
939.
End-stage renal disease (ESRD) with and/or without treatment by hemodialysis (HD) is associated with accelerated atherosclerosis,
leading to cardiovascular disease (CVD) including acute coronary syndromes. Therefore, the regulation of CVD is a crucial
issue for ESRD patients. Given the recent reports that paraoxonase-1 (PON-1) and ischemia-modified albumin (IMA) could predict
CVD-related mortality in ESRD, the two recent biomarkers may be useful for preventive strategies for CVD. This review paper
presents current data on the relationships between PON-1, IMA, and ESRD. Many studies have shown that circulating PON-1 activity
is lower in ESRD patients, and we have shown that its levels increase after HD. Although circulating IMA levels can increase
before HD in ESRD patients, there remains to be little data. Our pilot study has shown a significant inverse correlation between
PON-1 and IMA in ESRD patients. Although the pathogenic link between PON-1 and IMA remains speculative, considering both biomarkers
may provide new insights into the prevention of CVD in ESRD patients. 相似文献
940.
Tetsuya Adachi-Hagimori Manabu Shibao Hiroshi Tanaka Tomokazu Seko Kazuki Miura 《BioControl》2011,56(2):207-213
The green peach aphid [Myzus persicae (Sulzer)] and turnip aphid [Lipaphis erysimi (Kaltenbach)] are economically important pests with a worldwide distribution. We have evaluated the efficacy of releasing
adults and larvae of a flightless strain of the multicolored Asian lady beetle (Harmonia axyridis Pallas) as a control measure against these aphids on plants of non-heading Brassica cultivars. Both adults and larvae of H. axyridis were observed to be effective biocontrol agents, markedly decreasing the numbers of aphids. The residence duration of adults
was longer than that of larvae. The proportion of non-marketable plants damaged by aphids was lower in plots into which either
adults or adults and larvae of H. axyridis had been released. These results suggest that both adults and larvae of this flightless strain of H. axyridis are effective in controlling aphids on plants of non-heading Brassica cultivars. 相似文献