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101.
DEAD-box RNA helicase subunits of the Drosha complex are required for processing of rRNA and a subset of microRNAs 总被引:5,自引:0,他引:5
Fukuda T Yamagata K Fujiyama S Matsumoto T Koshida I Yoshimura K Mihara M Naitou M Endoh H Nakamura T Akimoto C Yamamoto Y Katagiri T Foulds C Takezawa S Kitagawa H Takeyama K O'Malley BW Kato S 《Nature cell biology》2007,9(5):604-611
MicroRNAs (miRNAs) control cell proliferation, differentiation and fate through modulation of gene expression by partially base-pairing with target mRNA sequences. Drosha is an RNase III enzyme that is the catalytic subunit of a large complex that cleaves pri-miRNAs with distinct structures into pre-miRNAs. Here, we show that both the p68 and p72 DEAD-box RNA helicase subunits in the mouse Drosha complex are indispensable for survival in mice, and both are required for primary miRNA and rRNA processing. Gene disruption of either p68 or p72 in mice resulted in early lethality, and in both p68(-/-) and p72(-/-) embryos, expression levels of a set of, but not all, miRNAs and 5.8S rRNA were significantly lowered. In p72(-/-) MEF cells, expression of p72, but not a mutant lacking ATPase activity, restored the impaired expression of miRNAs and 5.8S rRNA. Furthermore, we purified the large complex of mouse Drosha and showed it could generate pre-miRNA and 5.8S rRNA in vitro. Thus, we suggest that DEAD-box RNA helicase subunits are required for recognition of a subset of primary miRNAs in mDrosha-mediated processing. 相似文献
102.
Mehmet Aksoy Ali Ahiskalioglu Ilker Ince Mine Celik Aysenur Dostbil Ufuk Kuyrukluyildiz Durdu Altuner Nezahat Kurt Halis Suleyman 《Experimental Animals》2015,64(4):391-396
Thiopental sodium (TPS) needs to be applied together with adrenalin in order to establish
its analgesic effect in general anesthesia. We aimed to investigate the effect of TPS on
the claw pain threshold in rats and evaluated its relationship with endogenous adrenalin
(ADR), noradrenalin (NDR), and dopamine (DOP) levels. Intact and adrenalectomized rats
were used in the experiment. Intact animals were divided into the following groups: 15
mg/kg TPS (TS), 0.3 mg/kg ADR+15 mg/kg TPS (ATS) and 0.3 mg/kg ADR alone (ADR).
Adrenalectomized animals were divided into the following groups: 15 mg/kg TPS (A-TS), 0.3
mg/kg ADR+15 mg/kg TPS (A-ATS) and 0.3 mg/kg ADR alone (A-ADR). Claw pain threshold and
blood ADR, NDR, and DOP levels were measured. The TS group’s claw pain threshold was found
low. However, the claw pain thresholds of the ATS and ADR groups increased significantly.
In the A-TS group, the pain threshold decreased compared with normal, and in the A-ATS and
A-ADR groups, the pain threshold increased. TPS reduced the blood ADR levels in intact
rats; however, no significant changes were observed in the NDR and DOP levels. #TPS
provides hyperalgesia by reducing the production of ADR in rats. The present study shows
that to achieve analgesic activity, TPS needs to be applied together with ADR. 相似文献
103.
Increased expression levels of monocyte CCR2 and monocyte chemoattractant protein-1 in patients with diabetes mellitus 总被引:3,自引:0,他引:3
Mine S Okada Y Tanikawa T Kawahara C Tabata T Tanaka Y 《Biochemical and biophysical research communications》2006,344(3):780-785
Increased monocyte recruitment into subendothelial space in atherosclerotic lesions is one of the hallmarks of diabetic angiopathy. The aim of this study was to determine the state of peripheral blood monocytes in diabetes associated with atherosclerosis. Diabetic patients treated with/without an oral hypoglycemic agent and/or insulin for at least 1 year were recruited (n=106). We also included 24 non-diabetic control subjects. We measured serum levels of monocyte chemoattractant protein (MCP)-1, fasting plasma glucose (FPG), HbA1c, total cholesterol, triglyceride, body mass index (BMI), high sensitivity CRP (hs-CRP) and evaluated CCR2, CD36, CD68 expression on the surface of monocytes. Serum MCP-1 levels were significantly (p<0.05) higher in diabetic patients than in normal subjects. In diabetic patients, serum MCP-1 levels correlated significantly with FPG, HbA1c, triglyceride, BMI, and hs-CRP. The expression levels of CCR2, CD36, and CD68 on monocytes were significantly increased in diabetic patients and were more upregulated by MCP-1 stimulation. Our data suggest that elevated serum MCP-1 levels and increased monocyte CCR2, CD36, CD68 expression correlate with poor blood glucose control and potentially contribute to increased recruitment of monocytes to the vessel wall in diabetes mellitus. 相似文献
104.
105.
106.
The involvement of mitochondria and the caspase-9 activation pathway in rituximab-induced apoptosis in FL cells 总被引:1,自引:0,他引:1
Jonna Eeva Ulla Nuutinen Antti Ropponen Mikko Mättö Mine Eray Riikka Pellinen Jarmo Wahlfors Jukka Pelkonen 《Apoptosis : an international journal on programmed cell death》2009,14(5):687-698
Despite the wide use of anti-CD20 antibody rituximab in the cancer treatment of B cell malignancies, the signalling pathways
of CD20-induced apoptosis are still not understood. By using dominant negative (DN)-caspase-9 overexpressing follicular lymphoma
cells we demonstrated that the activation of caspase-9 was essential for rituximab-mediated apoptosis. The death receptor
pathway mediated by caspase-8 activation was not involved in rituximab-mediated apoptosis since overexpression of FLIPshort or FLIPlong proteins, inhibitors of caspase-8 activation, could not inhibit rituximab-induced apoptosis. However, the death receptor
pathway activation by anti-Fas antibodies showed an additive effect on rituximab-induced apoptosis. The stabilisation of the
mitochondrial outer membrane by Bcl-xL overexpression inhibited cell death, showing the important role of mitochondria in rituximab-induced apoptosis. Interestingly,
the rituximab-induced release of cytochrome c and collapse of mitochondrial membrane potential were regulated by caspase-9. We suggest that caspase-9 and downstream caspases
may feed back to mitochondria to amplify mitochondrial disruption during intrinsic apoptosis. 相似文献
107.
We investigated the acceptor substrate specificities of marine bacterial α-(2→3)-sialyltransferase cloned from Photobacterium sp. JT-ISH-224 and α-(2→6)-sialyltransferase cloned from Photobacterium damselae JT0160 using several saccharides as acceptor substrates. After purifying the enzymatic reaction products, we confirmed their structure by NMR spectroscopy. The α-(2→3)-sialyltransferase transferred N-acetylneuraminic acid (Neu5Ac) from cytidine 5′-monophospho-N-acetylneuraminic acid (CMP-Neu5Ac) to the β-anomeric hydroxyl groups of mannose (Man) and α-Manp-(1→6)-Manp, and α-(2→6)-sialyltransferase transferred N-acetylneuraminic acid to the 6-OH groups of the non-reducing end galactose residues in β-Galp-(1→3)-GlcpNAc and β-Galp-(1→6)-GlcpNAc. 相似文献
108.
Mine Gulaboglu Bunyamin Borekci Ilhan Delibas 《Biological trace element research》2010,136(3):249-257
The aim of this study was to investigate the urine iodine concentration in women with severe preeclampsia and in healthy women
in Erzurum, Turkey. Urine specimens were obtained from 40 severe preeclampsia and 18 healthy pregnant women. Urinary iodine
levels were determined by the Foss method based on the Sandell–Kolthoff reaction. The urinary iodine level for women with
severe preeclampsia was 4.25 ± 2.7 μg/dL, lower than 20.89 ± 6.4 μg/dL of urinary iodine for healthy pregnant women (p < 0.001). Blood magnesium concentration was found to be 1.63 ± 0.05 mg/dL for women with severe preeclampsia, which is lower
than that of healthy pregnant women (1.87 ± 0.05 mg/dL; p < 0.001). There was a positive correlation between urinary iodine level and blood magnesium level in pregnant women with
preeclampsia (Pearson correlation coefficient = 0.43; p < 0.01). However, there was no correlation between urinary iodine level and blood magnesium level in healthy pregnant women.
There was no difference in thyroid hormone levels (T4, TSH, FT4) between women with severe preeclampsia and healthy pregnant
women. However, there was a difference in T3 thyroid hormone levels between women with severe preeclampsia (1.86 ± 0.4 μg/dL)
and healthy pregnant women (1.45 ± 0.3 μg/dL; p < 0.001). There was also a difference in FT3 between women with severe preeclampsia (2.77 ± 0.4 pg/mL) and healthy pregnant
women (2.41 ± 0.5 μg/dL; p < 0.01). Urinary iodine excretion is currently the most convenient laboratory marker of iodine deficiency. The method is
useful for the rapid and low-cost assessment of iodine deficiency. Our results suggested that urinary iodine concentration
might be a useful marker for prediagnosing preeclamptic women. In addition, iodine supplementation may also be considered
for preeclamptic therapy. 相似文献
109.
Cellulase production on glucose-based media by the UV-irradiated mutants of Trichoderma reesei 总被引:2,自引:0,他引:2
Masakazu Ike Jeung-yil Park Mine Tabuse Ken Tokuyasu 《Applied microbiology and biotechnology》2010,87(6):2059-2066
From 22,791 mutants of a cellulase hyper-producing strain of Trichoderma reesei (Hypocrea jecorina), ATCC66589, as the parent, we selected two mutants, M2-1 and M3-1, that produce cellulases in media containing both cellulose
and glucose. The mutation enabled the mutants to produce cellulases, which were measured as p-nitrophenyl β-d-lactopyranoside-hydrolyzing activities, in media with glucose as a sole carbon source, although M2-1 exhibited different
sensitivities to glucose from M3-1. When the mutants were grown for 8 days on a medium with cellulose as a sole carbon source,
the filter-paper-degrading activities (FPAs) per gram of cellulose were 257 and 281 U for M2-1 and M3-1, respectively, values
that were 1.1–1.2 times higher than that of the parental strain. Cellulase production by M2-1 and M3-1 on a medium with a
continuously fed mixture of glucose and cellobiose resulted in 214 and 210 U of FPA/gram carbon sources, respectively, whereas
less efficient production (140 U of FPA/gram carbon source) was achieved by the parental strain. The improved cellulase productivity
of the mutants allows us to use glucose as a carbon source for efficient on-site production of cellulases with quality/quantity-controlled feeding of soluble carbon sources and inducers. 相似文献
110.
Vladimir Novitsky Rui Wang Hermann Bussmann Shahin Lockman Marianna Baum Roger Shapiro Ibou Thior Carolyn Wester C. William Wester Anthony Ogwu Aida Asmelash Rosemary Musonda Adriana Campa Sikhulile Moyo Erik van Widenfelt Madisa Mine Claire Moffat Mompati Mmalane Joseph Makhema Richard Marlink Peter Gilbert George R. Seage III Victor DeGruttola M. Essex 《PloS one》2010,5(4)
The first aim of the study is to assess the distribution of HIV-1 RNA levels in subtype C infection. Among 4,348 drug-naïve HIV-positive individuals participating in clinical studies in Botswana, the median baseline plasma HIV-1 RNA levels differed between the general population cohorts (4.1–4.2 log10) and cART-initiating cohorts (5.1–5.3 log10) by about one log10. The proportion of individuals with high (≥50,000 (4.7 log10) copies/ml) HIV-1 RNA levels ranged from 24%–28% in the general HIV-positive population cohorts to 65%–83% in cART-initiating cohorts. The second aim is to estimate the proportion of individuals who maintain high HIV-1 RNA levels for an extended time and the duration of this period. For this analysis, we estimate the proportion of individuals who could be identified by repeated 6- vs. 12-month-interval HIV testing, as well as the potential reduction of HIV transmission time that can be achieved by testing and ARV treating. Longitudinal analysis of 42 seroconverters revealed that 33% (95% CI: 20%–50%) of individuals maintain high HIV-1 RNA levels for at least 180 days post seroconversion (p/s) and the median duration of high viral load period was 350 (269; 428) days p/s. We found that it would be possible to identify all HIV-infected individuals with viral load ≥50,000 (4.7 log10) copies/ml using repeated six-month-interval HIV testing. Assuming individuals with high viral load initiate cART after being identified, the period of high transmissibility due to high viral load can potentially be reduced by 77% (95% CI: 71%–82%). Therefore, if HIV-infected individuals maintaining high levels of plasma HIV-1 RNA for extended period of time contribute disproportionally to HIV transmission, a modified “test-and-treat” strategy targeting such individuals by repeated HIV testing (followed by initiation of cART) might be a useful public health strategy for mitigating the HIV epidemic in some communities. 相似文献