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71.
72.
Kim MK  Park SH  Cho HD  Cho SJ  Kim A  Kim HK  Yeom BW  Choi JS  Kim CH 《Acta cytologica》2001,45(3):459-464
BACKGROUND: Primary pulmonary paragangliomas are rare tumors. To our knowledge, there is no prior report on fine needle aspiration cytology (FNAC) in pulmonary paraganglioma. CASE: A 34-year-old man presented with an incidentally found solitary pulmonary mass. FNAC showed papillarylike clusters of epithelioid cells with round to oval nuclei, evenly dispersed chromatin, micronucleoli and occasional anisonucleosis. These cytologic features were suggestive of a sclerosing hemangioma or bronchioloalveolar carcinoma. A right lower lobectomy revealed a primary pulmonary paraganglioma. CONCLUSION: The possibility of pulmonary paraganglioma should be considered in the differential diagnosis of FNAC showing pseudopapillary clusters of epithelioid cells.  相似文献   
73.
The role of RhoA in the germinal vesicle breakdown of mouse oocytes   总被引:1,自引:0,他引:1  
We have investigated a new role of RhoA in the germinal vesicle breakdown (GVBD) of mouse oocytes. First, RhoA was identified by immunostaining and ADP-ribosylation in germinal vesicle (GV) stage-oocytes. RhoA was mainly localized in the ooplasmic area, but rarely detected in germinal vesicle. Incubation of oocyte extract with C3 transferase induced a strong ADP-ribosylation at about 25 kDa. Incubation of GV-stage oocytes in culture medium induced the spontaneous maturation to GVBD by about 78 and 87% of total oocytes at 1 and 3 h, respectively. However, microinjection of C3 transferase into GV-stage oocytes significantly inhibited GVBD at 1 (GVBD = 29%) and 3 h (GVBD = 49%). To study the role of reactive oxygen species (ROS) in the oocyte maturation, the level of intra-oocyte ROS was measured using a ROS-specific fluorescent dye H(2)DCFDA during the oocyte maturation. Spontaneous maturation of GV-stage oocytes induced a significant increase of ROS at 3 h by about twofold over the control level and then the increased level was maintained until 6 h. However, microinjection of C3 transferase inhibited the production of intra-oocyte ROS. Incubation with ROS scavengers, N-acetyl-l-cysteine and catalase, blocked the ROS increase. The ROS scavengers also significantly inhibited GVBD, as did C3 transferase. Thus, it was proposed that RhoA was involved in the GVBD, possibly by the production of ROS in mouse oocytes.  相似文献   
74.
A continuous treatment system combining a packed-bed column and a two-phase partitioning bioreactor has been designed to treat high-concentration benzene-containing gas streams. 1-Octadecene was used in a closed loop as an absorbant to scrub benzene in the counter-current column, after which it was transferred to the two-phase partitioning bioreactor to partition benzene into the 1 l aqueous phase for degradation by Klebsiella sp. The solvent was then recirculated back to the absorber. A gas stream containing 20 mg l–1 benzene at a flow rate of 60 l h–1 was introduced to the system, and the benzene was degraded at a biological removal efficiency of 87% at steady state.  相似文献   
75.
76.

Purpose

Human sodium/iodide symporter (hNIS) protein is a membrane glycoprotein that transports iodide ions into thyroid cells. The function of this membrane protein is closely regulated by post-translational glycosylation. In this study, we measured glycosylation-mediated changes in subcellular location of hNIS and its function of iodine uptake.

Methods

HeLa cells were stably transfected with hNIS/tdTomato fusion gene in order to monitor the expression of hNIS. Cellular localization of hNIS was visualized by confocal microscopy of the red fluorescence of tdTomato. The expression of hNIS was evaluated by RT-PCR and immunoblot analysis. Functional activity of hNIS was estimated by radioiodine uptake. Cyclic AMP (cAMP) and tunicamycin were used to stimulate and inhibit glycosylation, respectively. In vivo images were obtained using a Maestro fluorescence imaging system.

Results

cAMP-mediated Glycosylation of NIS resulted in increased expression of hNIS, stimulating membrane translocation, and enhanced radioiodine uptake. In contrast, inhibition of glycosylation by treatment with tunicamycin dramatically reduced membrane translocation of intracellular hNIS, resulting in reduced radioiodine uptake. In addition, our hNIS/tdTomato fusion reporter successfully visualized cAMP-induced hNIS expression in xenografted tumors from mouse model.

Conclusions

These findings clearly reveal that the membrane localization of hNIS and its function of iodine uptake are glycosylation-dependent, as our results highlight enhancement of NIS expression and glycosylation with subsequent membrane localization after cAMP treatment. Therefore, enhancing functional NIS by the increasing level of glycosylation may be suggested as a promising therapeutic strategy for cancer patients who show refractory response to conventional radioiodine treatment.  相似文献   
77.
DNA double-strand breaks (DSBs) are the most severe type of DNA damage and are primarily repaired by non-homologous end joining (NHEJ) and homologous recombination (HR) in the G1 and S/G2 phase, respectively. Although CtBP-interacting protein (CtIP) is crucial in DNA end resection during HR following DSBs, little is known about how CtIP levels increase in an S phase-specific manner. Here, we show that Serpine mRNA binding protein 1 (SERBP1) regulates CtIP expression at the translational level in S phase. In response to camptothecin-mediated DNA DSBs, CHK1 and RPA2 phosphorylation, which are hallmarks of HR activation, was abrogated in SERBP1-depleted cells. We identified CtIP mRNA as a binding target of SERBP1 using RNA immunoprecipitation-coupled RNA sequencing, and confirmed SERBP1 binding to CtIP mRNA in S phase. SERBP1 depletion resulted in reduction of polysome-associated CtIP mRNA and concomitant loss of CtIP expression in S phase. These effects were reversed by reconstituting cells with wild-type SERBP1, but not by SERBP1 ΔRGG, an RNA binding defective mutant, suggesting regulation of CtIP translation by SERBP1 association with CtIP mRNA. These results indicate that SERBP1 affects HR-mediated DNA repair in response to DNA DSBs by regulation of CtIP translation in S phase.  相似文献   
78.
In the present study, a laboratory scale anoxic/oxic (A/O) reactor is used for the removal of nutrient and sludge reduction. Phosphorus removal was achieved through simultaneous precipitation, and sludge production was reduced through thermochemical pretreatment. The main objective of the study was to investigate the influence of sludge pretreatment on the nitrification rate. Total phosphorus in the effluent was maintained around 0.5 ~ 1.0 mg/L by simultaneous precipitation, using coagulant alum at 2.2 mole ratio. Before simultaneous precipitation, the nitrification rate of the A/O reactor was found to be 0.050 g N-NH4 +/g MLVSS.d. The thermochemical sludge pretreatment began on the 120th day at pH 11 and 80°C. The initiation of sludge pretreatment brought about a significant reduction of the A/O reactor nitrification rate, which fell to 0.038 g N-NH4 +/g MLVSS/day. The effect of sludge pretreatment was reflected in the reduction of the nitrogen removal efficiency from 85 to 74%. Recycling of the thermochemically pretreated sludge accounted for 57% sludge reduction, which had an adverse influence on the nitrification rate of the system.  相似文献   
79.
The explosion of data and transactions demands a creative approach for data processing in a variety of applications. Research on remote memory systems (RMSs), so as to exploit the superior characteristics of dynamic random access memory (DRAM), has been performed for many decades, and today’s information explosion galvanizes researchers into shedding new light on the technology. Prior studies have mainly focused on architectural suggestions for such systems, highlighting different design rationale. These studies have shown that choosing the appropriate applications to run on an RMS is important in fully utilizing the advantages of remote memory. This article provides an extensive performance evaluation for various types of data processing applications so as to address the efficacy of an RMS by means of a prototype RMS with reliability functionality. The prototype RMS used is a practical kernel-level RMS that renders large memory data processing feasible. The abstract concept of remote memory was materialized by borrowing unused local memory in commodity PCs via a high speed network capable of Remote Direct Memory Access (RDMA) operations. The prototype RMS uses remote memory without any part of its computation power coming from remote computers. Our experimental results suggest that an RMS can be practical in supporting the rigorous demands of commercial in memory database systems that have high data access locality. Our evaluation also convinces us of the possibility that a reliable RMS can satisfy both the high degree of reliability and efficiency for large memory data processing applications whose data access pattern has high locality.  相似文献   
80.
Yoon  Joo Young  Yeom  Jeonghun  Lee  Heebum  Kim  Kyutae  Na  Seungjin  Park  Kunsoo  Paek  Eunok  Lee  Cheolju 《BMC bioinformatics》2011,12(1):1-12

Background

Continuing research into the global multiple sequence alignment problem has resulted in more sophisticated and principled alignment methods. Unfortunately these new algorithms often require large amounts of time and memory to run, making it nearly impossible to run these algorithms on large datasets. As a solution, we present two general methods, Crumble and Prune, for breaking a phylogenetic alignment problem into smaller, more tractable sub-problems. We call Crumble and Prune meta-alignment methods because they use existing alignment algorithms and can be used with many current alignment programs. Crumble breaks long alignment problems into shorter sub-problems. Prune divides the phylogenetic tree into a collection of smaller trees to reduce the number of sequences in each alignment problem. These methods are orthogonal: they can be applied together to provide better scaling in terms of sequence length and in sequence depth. Both methods partition the problem such that many of the sub-problems can be solved independently. The results are then combined to form a solution to the full alignment problem.

Results

Crumble and Prune each provide a significant performance improvement with little loss of accuracy. In some cases, a gain in accuracy was observed. Crumble and Prune were tested on real and simulated data. Furthermore, we have implemented a system called Job-tree that allows hierarchical sub-problems to be solved in parallel on a compute cluster, significantly shortening the run-time.

Conclusions

These methods enabled us to solve gigabase alignment problems. These methods could enable a new generation of biologically realistic alignment algorithms to be applied to real world, large scale alignment problems.  相似文献   
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