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Maxillary molar root and canal morphology of Neolithic and modern Chinese. Arch Oral Biol 2021; 131:105272. [PMID: 34600333 DOI: 10.1016/j.archoralbio.2021.105272] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2021] [Revised: 09/12/2021] [Accepted: 09/21/2021] [Indexed: 01/17/2023]
Abstract
OBJECTIVE This study aimed to characterize Neolithic human maxillary molars from archeological remains at the Jiaojia site, Shandong, China, and compare their ultrastructural features with sex and age-matched modern locals. DESIGN Maxillary first (n = 86) and second (n = 80) molars in 5000-year-old individuals (n = 50) from the Jiaojia site were scanned by cone-beam computed tomography (CBCT). Sex and age-matched control groups were assigned from oral surgical patients at Shandong University. Images were analyzed for crown size, root length, root morphology, canal inter-orifice distances, mesiobuccal canal morphology, and second mesiobuccal (MB2) canal prevalence and location. Neolithic and modern values were compared statistically using Chi-squared and Mann-Whitney test at p < .05. RESULTS Crown and root size were smaller, and canal inter-orifice distances were shorter in Neolithic maxillary molars than their modern counterparts. For mesiobuccal roots, Weine's Type I single canals were the most prevalent in Neolithic and modern first and second molars. MB2 canal prevalence were not significantly different (p > .05) in Neolithic (53.3%) or modern (60.5%) first molars, and Neolithic (11.3%) or modern (21.3%) second molars. But, MB2 prevalence was significantly higher for modern than ancient male first (p = .032) and second (p = .005) molars. Additionally, MB2 were located more mesially and closer to MB1 in Neolithic than modern molars. CONCLUSIONS Maxillary molar root and canal morphology of ancient 5000-year-old remains at the Jiaojia site resemble that of local patients. A trend towards larger tooth size, and more dispersed MB2 canals over this short evolutionary period warrants additional investigation.
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Stacking Fault Energy Analyses of Additively Manufactured Stainless Steel 316L and CrCoNi Medium Entropy Alloy Using In Situ Neutron Diffraction. Sci Rep 2020; 10:1350. [PMID: 31992801 PMCID: PMC6987211 DOI: 10.1038/s41598-020-58273-3] [Citation(s) in RCA: 40] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2019] [Accepted: 01/10/2020] [Indexed: 11/08/2022] Open
Abstract
Stacking fault energies (SFE) were determined in additively manufactured (AM) stainless steel (SS 316 L) and equiatomic CrCoNi medium-entropy alloys. AM specimens were fabricated via directed energy deposition and tensile loaded at room temperature. In situ neutron diffraction was performed to obtain a number of faulting-embedded diffraction peaks simultaneously from a set of (hkl) grains during deformation. The peak profiles diffracted from imperfect crystal structures were analyzed to correlate stacking fault probabilities and mean-square lattice strains to the SFE. The result shows that averaged SFEs are 32.8 mJ/m2 for the AM SS 316 L and 15.1 mJ/m2 for the AM CrCoNi alloys. Meanwhile, during deformation, the SFE varies from 46 to 21 mJ/m2 (AM SS 316 L) and 24 to 11 mJ/m2 (AM CrCoNi) from initial to stabilized stages, respectively. The transient SFEs are attributed to the deformation activity changes from dislocation slip to twinning as straining. The twinning deformation substructure and atomic stacking faults were confirmed by electron backscatter diffraction (EBSD) and transmission electron microscopy (TEM). The significant variance of the SFE suggests the critical twinning stress as 830 ± 25 MPa for the AM SS 316 L and 790 ± 40 MPa for AM CrCoNi, respectively.
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Ischemic Preconditioning Produces Comparable Protection Against Hepatic Ischemia/Reperfusion Injury Under Isoflurane and Sevoflurane Anesthesia in Rats. Transplant Proc 2018; 49:2188-2193. [PMID: 29149981 DOI: 10.1016/j.transproceed.2017.07.002] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2017] [Accepted: 07/30/2017] [Indexed: 11/27/2022]
Abstract
BACKGROUND Various volatile anesthetics and ischemic preconditioning (IP) have been demonstrated to exert protective effect against ischemia/reperfusion (I/R) injury in liver. We aimed to determine whether application of IP under isoflurane and sevoflurane anesthesia would confer protection against hepatic I/R injury in rats. METHODS Thirty-eight rats weighing 270 to 300 grams were randomly divided into 2 groups: isoflurane (1.5%) and sevoflurane (2.5%) anesthesia groups. Each group was subdivided into sham (n = 3), non-IP (n = 8; 45 minutes of hepatic ischemia), and IP (n = 8, IP consisting of 10-minute ischemia plus 15-minute reperfusion before prolonged ischemia) groups. The degree of hepatic injury and expressions of B-cell lymphoma 2 (Bcl-2) and caspase 3 were compared at 2 hours after reperfusion. RESULTS Hepatic ischemia induced significant degree of I/R injuries in both isoflurane and sevoflurane non-IP groups. In both anesthetic groups, introduction of IP dramatically attenuated I/R injuries as marked by significantly lower aspartate aminotransferase and aminotransferase levels and better histologic grades compared with corresponding non-IP groups. There were 2.3- and 1.7-fold increases in Bcl-2 mRNA levels in isoflurane and sevoflurane IP groups, respectively, compared with corresponding non-IP groups (both P < .05). Caspase 3 level was significantly high in the isoflurane non-IP group compared with the sham group; however, there were no differences among the sevoflurane groups. CONCLUSIONS The degree of hepatic I/R injury was significantly high in both isoflurane and sevoflurane groups in rats. However, application of IP significantly protected against I/R injury in both volatile anesthetic groups to similar degrees, and upregulation of Bcl-2 might be an important mechanism.
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Population genetic characterization of the Japanese oak silkmoth, Antheraea yamamai (Lepidoptera: Saturniidae), using novel microsatellite markers and mitochondrial DNA gene sequences. GENETICS AND MOLECULAR RESEARCH 2017; 16:gmr-16-02-gmr.16029608. [PMID: 28407192 DOI: 10.4238/gmr16029608] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
The Japanese oak silkmoth, Antheraea yamamai Guérin-Méneville, 1861 (Lepidoptera: Saturniidae), is an important natural resource of industrial value for silk fiber production. Owing to a lack of geographic and population genetic information, systematic domestication of An. yamamai has not been possible yet. In this study, 10 microsatellite markers developed using next-generation sequencing and two mitochondrial DNA (mtDNA) gene sequences (COI and ND4) were used to investigate the genetic variation and geographic structure of An. yamamai populations in South Korea. The two mtDNA gene sequences revealed very low total genetic variation and, consequently, low geographic variation, validating the use of more variable molecular markers. Genotyping of 76 An. yamamai individuals from nine localities in South Korea showed that the observed number of alleles at each locus ranged from 3 to 26, the polymorphism information content was 0.2990-0.9014, the observed and expected heterozygosities were 0.3252-0.9076 and 0.2500-0.9054, respectively, and FIS was -0.654-0.520. The population-based FIS, FST, RST, and global Mantel tests all suggested that the An. yamamai populations were overall well-interconnected, suggesting that any population can be used as a genetic source for domestication. Nevertheless, STRUCTURE analyses using microsatellite data and mtDNA sequences indicated the presence of two genetic pools in many populations, although a plausible explanation for this observation requires further studies.
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Effect of dietary supplementation with a probiotic (Enterococcus faecium) on production performance, excreta microflora, ammonia emission, and nutrient utilization in ISA brown laying hens. Poult Sci 2016; 95:2829-2835. [PMID: 27422665 DOI: 10.3382/ps/pew241] [Citation(s) in RCA: 44] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Revised: 11/02/2015] [Accepted: 06/10/2016] [Indexed: 11/20/2022] Open
Abstract
The ban on the use of antibiotics as growth promoters due to resistance issues has urged scientists to find alternatives to antibiotics. Entercoccus faecium is one of the probiotics which have been used as an alternative to antibiotics in the livestock industry. This study was conducted to evaluate the effect of probiotic (Enterococcus faecium DSM 7134) supplementation on production performance, feed intake, egg quality, excreta microflora, ammonia emission, and nutrient utilization in laying hens. A total of 288 ISA brown laying hens were used in a 27 wk feeding experiment and randomly assigned to 3 dietary treatments with 8 replicates of 12 birds each. The treatments were CON (basal diet), PB1 (basal diet + 0.005% E. faecium), and PB2 (basal diet + 0.01% E. faecium). Overall, our results demonstrated that E. faecium supplementation resulted in a significant increase in egg production, egg shell thickness, and nutrient digestibility (dry matter, nitrogen, and energy) in laying hens, and a significant reduction in fecal coliform counts as compared with CON. The shift of excreta fecal microbial composition by E. faecium supplementation was accompanied by increased nutrient retention and reduction in nutrient excretion, leading to improved nutrient digestibility and reduced excreta ammonia emission. Overall, E. faecium supplementation appears to have a beneficial effect in ISA brown laying hens and should be considered as a positive diet supplement to use in the industry.
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Activation of nuclear PTEN by inhibition of Notch signaling induces G2/M cell cycle arrest in gastric cancer. Oncogene 2015; 35:251-60. [DOI: 10.1038/onc.2015.80] [Citation(s) in RCA: 70] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2014] [Revised: 12/25/2014] [Accepted: 02/16/2015] [Indexed: 12/19/2022]
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Effect of Bacillus subtilis C-3102 spores as a probiotic feed supplement on growth performance, noxious gas emission, and intestinal microflora in broilers. Poult Sci 2014; 93:3097-103. [PMID: 25260523 DOI: 10.3382/ps.2014-04086] [Citation(s) in RCA: 130] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Bacillus subtilis C-3102 has been used as a direct-fed microbial or probiotic product since 1986 to improve production performance in broilers worldwide. This study was conducted to determine and confirm the effect of B. subtilis C-3102 spore supplementation to feed on growth performance, nutrient digestibility, carcass quality, blood profiles, noxious gas emission, and intestinal and excreta microflora in broilers. A total of 816 one-day-old male Ross 308 broilers (46.06 ± 0.67 g) were used in a 5-wk study with Calsporin, B. subtilis final product (1.0 × 10(9) cfu/g of B. subtilis). Broilers were randomly allotted to 1 of 3 dietary treatments consisting of 16 replicate cages with 17 broilers each: I) CON (control, basal diet), II) BS300 (CON + 300 mg of B. subtilis/kg of feed), and III) BS600 (CON + 600 mg of B. subtilis/kg of feed). Regarding probiotic effect, B. subtilis significantly increased Lactobacillus counts in the cecum, ileal, and excreta, and reduced Escherichia coli counts in the cecum and excreta, compared with CON. In addition, supplementation also tended to reduce Clostridium perfringens counts in the large intestine and excreta, while linearly reducing Salmonella counts in the cecum, ileal, large intestine, and excreta, compared with CON. Regarding growth performance, B. subtilis enhanced ADG in the starter and overall experimental periods, without any effects on feed intake compared with CON. Consequently, feed conversion ratio in the grower-finisher and overall experimental periods decreased significantly. The inclusion of B. subtilis improved the digestibility of DM and gross energy, as well as reducing ammonia emission, compared with CON. No significant difference in breast muscle color, water holding capacity, and drip loss, and relative organ weights, as well as in white blood cells, red blood cells, lymphocyte counts, and IgG amount, were observed. Overall, B. subtilis C-1302 is capable of providing a probiotic effect leading to improved growth performance and feed efficiency, due to the manipulation of intestinal microflora, with minimal side effects in broilers.
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Bcl2-associated athanogene 3 interactome analysis reveals a new role in modulating proteasome activity. Mol Cell Proteomics 2013; 12:2804-19. [PMID: 23824909 DOI: 10.1074/mcp.m112.025882] [Citation(s) in RCA: 57] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Bcl2-associated athanogene 3 (BAG3), a member of the BAG family of co-chaperones, plays a critical role in regulating apoptosis, development, cell motility, autophagy, and tumor metastasis and in mediating cell adaptive responses to stressful stimuli. BAG3 carries a BAG domain, a WW domain, and a proline-rich repeat (PXXP), all of which mediate binding to different partners. To elucidate BAG3's interaction network at the molecular level, we employed quantitative immunoprecipitation combined with knockdown and human proteome microarrays to comprehensively profile the BAG3 interactome in humans. We identified a total of 382 BAG3-interacting proteins with diverse functions, including transferase activity, nucleic acid binding, transcription factors, proteases, and chaperones, suggesting that BAG3 is a critical regulator of diverse cellular functions. In addition, we characterized interactions between BAG3 and some of its newly identified partners in greater detail. In particular, bioinformatic analysis revealed that the BAG3 interactome is strongly enriched in proteins functioning within the proteasome-ubiquitination process and that compose the proteasome complex itself, suggesting that a critical biological function of BAG3 is associated with the proteasome. Functional studies demonstrated that BAG3 indeed interacts with the proteasome and modulates its activity, sustaining cell survival and underlying resistance to therapy through the down-modulation of apoptosis. Taken as a whole, this study expands our knowledge of the BAG3 interactome, provides a valuable resource for understanding how BAG3 affects different cellular functions, and demonstrates that biologically relevant data can be harvested using this kind of integrated approach.
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Risk factors and colonization status of methicillin-resistant Staphylococcus aureus among newly admitted newborns in neonatial intensive care unit. BMC Proc 2011. [PMCID: PMC3239794 DOI: 10.1186/1753-6561-5-s6-p6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
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Abstract P2-09-01: Serial [18F] FDG-PET after the 2nd Cycle of Preoperative Chemotherapy Is Predictive for Pathological Complete Response in Stage II/III Breast Cancer. Cancer Res 2010. [DOI: 10.1158/0008-5472.sabcs10-p2-09-01] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
Purpose: One of substudies of the prospective trials aimed to evaluate the usefulness of serial [18F] 2-fluoro-2-deoxy-D-glucose-positron emission tomography ([18F] FDG-PET) for predicting pathological complete response (pCR) in stage II/III breast cancer with preoperative chemotherapy (PST).
Methods: Serial PET was undertaken in 57 breast cancer patients enrolled in three different neoadjuvant trials: 35 patients from a phase II study with paclitaxel/gemcitabine/trastuzumab with ClinicalTrial.gov NCT 00532857, 9 patients from a phase Ib study with paclitaxel/gemcitabine/lapatinib with ClinicalTrial.gov NCT 01133912, and 13 patients from a phase Ib with paclitaxel/gemcitabine/sunitinib with ClinicalTrial.gov NCT0 1070706. All patients received 6 cycles of PST followed by surgery and radiotherapy. We assessed the peak standardized uptake value (SUVp) in the primary tumor at the baseline and after the 2nd cycle (37 patients) or after completion (20 patients) of 6 cycles of PST, and calculated the reduction rate (RR) of the SUVp. Pathological response was classified into pCR and non-pCR. To compare the mean of SUVp and RR of SUVp between different response groups, two-way tables and chi-square tests were used
Results: Fifteen (40.6%) of 37 patients who took repeat PET after the 2nd PST and 15 (75%) of 20 patients after completion of PST achieved a pCR with overall pCR rate of 52.6% in the primary tumor. In patients with repeat PET after the 2nd PST, post-treatment SUVp and RR of the SUVp in primary tumors were significantly different by the pathological response (post-treatment SUVp, 1.54 ± 0.63 in pCR vs 2.54 ± 1.06 in non-pCR, P=0.002; RR of the SUVp, 79.2% ± 11.9% in pCR vs 68.9% ± 15.4% in non-pCR, P=0.03). However, in patients with repeat PET after completion of PST, there were no statistical differences of these values (post-treatment SUVp, 1.09 ± 0.63 in pCR vs 1.29 ± 0.36 in non-pCR, P=0.42; RR of the SUVp, 83.7% ± 14.0% in pCR vs 67.5% ± 21.1% in non-pCR, P=0.17)
Conclusions: This study demonstrated that repeat PET after the 2nd cycle of PST, not after completion of PST could predict pCR in stage II/III breast cancer with preoperative chemotherapy. Acknowledgement NCC Grant #0910320.
Citation Information: Cancer Res 2010;70(24 Suppl):Abstract nr P2-09-01.
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Profiling the human protein-DNA interactome reveals ERK2 as a transcriptional repressor of interferon signaling. Cell 2009; 139:610-22. [PMID: 19879846 DOI: 10.1016/j.cell.2009.08.037] [Citation(s) in RCA: 311] [Impact Index Per Article: 20.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2008] [Revised: 07/13/2009] [Accepted: 08/20/2009] [Indexed: 11/28/2022]
Abstract
Protein-DNA interactions (PDIs) mediate a broad range of functions essential for cellular differentiation, function, and survival. However, it is still a daunting task to comprehensively identify and profile sequence-specific PDIs in complex genomes. Here, we have used a combined bioinformatics and protein microarray-based strategy to systematically characterize the human protein-DNA interactome. We identified 17,718 PDIs between 460 DNA motifs predicted to regulate transcription and 4,191 human proteins of various functional classes. Among them, we recovered many known PDIs for transcription factors (TFs). We identified a large number of unanticipated PDIs for known TFs, as well as for previously uncharacterized TFs. We also found that over three hundred unconventional DNA-binding proteins (uDBPs)--which include RNA-binding proteins, mitochondrial proteins, and protein kinases--showed sequence-specific PDIs. One such uDBP, ERK2, acts as a transcriptional repressor for interferon gamma-induced genes, suggesting important biological roles for such proteins.
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Comparison of the adductor pollicis, orbicularis oculi, and corrugator supercilii as indicators of adequacy of muscle relaxation for tracheal intubation. Br J Anaesth 2009; 102:869-74. [PMID: 19376787 DOI: 10.1093/bja/aep064] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
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Comparison of a novel teeth-protecting mouthpiece with a traditional device in preventing endoscopy-related complications involving teeth or temporomandibular joint: a multicenter randomized trial. Endoscopy 2008; 40:472-7. [PMID: 18543135 DOI: 10.1055/s-2007-995647] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/10/2022]
Abstract
BACKGROUND AND STUDY AIMS After upper endoscopy, patients have complained of symptoms involving teeth or the temporomandibular joint; however, these endoscopy-related complications are usually ignored with few attempts to prevent them. The aim of this study was to identify the incidence of endoscopy-related complications involving teeth or temporomandibular joint, and to compare the effectiveness of a newly developed teeth-protecting mouthpiece (TPM) with a traditional mouthpiece (the MB-142) in preventing these complications. PATIENTS AND METHODS 872 patients from 28 centers, who were undergoing their first upper endoscopy, were randomly assigned to TPM and MB-142 groups. At 3 - 4 days after the procedure, the occurrence of endoscopy-related complications involving the teeth or the temporomandibular joint was investigated using a structured questionnaire. Finally 865 patients (TPM group, n = 423; MB-142, n = 442) responded to this questionnaire and were included in the analysis. RESULTS Overall, the incidence of complications was significantly lower in the TPM than in the MB-142 group (0.9% vs. 3.2%). With stratification according to sedation status, in nonsedated patients no significant difference was found between the two groups (0.7% vs. 0.9%). In sedated patients, however, the TPM group showed a significantly lower incidence of complication than the MB-142 group (1.7% vs. 11.6%). Clinically serious problems such as a tooth fracture or a loose tooth occurred only in sedated patients in the MB-142 group. CONCLUSIONS The TPM showed an advantage over the MB-142 mouthpiece for preventing endoscopy-related complications involving teeth or the temporomandibular joint.
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Global gene expression during nitrogen starvation in the rice blast fungus, Magnaporthe grisea. Fungal Genet Biol 2006; 43:605-17. [PMID: 16731015 DOI: 10.1016/j.fgb.2006.03.005] [Citation(s) in RCA: 77] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2005] [Revised: 02/15/2006] [Accepted: 03/24/2006] [Indexed: 01/28/2023]
Abstract
Efficient regulation of nitrogen metabolism likely plays a role in the ability of fungi to exploit ecological niches. To learn about regulation of nitrogen metabolism in the rice blast pathogen Magnaporthe grisea, we undertook a genome-wide analysis of gene expression under nitrogen-limiting conditions. Five hundred and twenty genes showed increased transcript levels at 12 and 48 h after shifting the fungus to media lacking nitrate as a nitrogen source. Thirty-nine of these genes have putative functions in amino acid metabolism and uptake, and include the global nitrogen regulator in M. grisea, NUT1. Evaluation of seven nitrogen starvation-induced genes revealed that all were expressed during rice infection. Targeted gene replacement on one such gene, the vacuolar serine protease, SPM1, resulted in decreased sporulation and appressorial development as well as a greatly attenuated ability to cause disease. Data are discussed in the context of nitrogen metabolism under starvation conditions, as well as conditions potentially encountered during invasive growth in planta.
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Pioglitazone, a synthetic ligand for PPARγ, induces apoptosis in RB-deficient human colorectal cancer cells. Apoptosis 2006; 11:401-11. [PMID: 16520894 DOI: 10.1007/s10495-006-4003-z] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
No published data are available about the expression of peroxisome proliferator-activated receptor gamma (PPARgamma) and the role of PPARgamma in retinoblastoma protein (RB)-deficient human colorectal cancer (CRC) cells (SNU-C4 and SNU-C2A). Our aim was to investigate whether PPARgamma is expressed in SNU-C4 and SNU-C2A cells and to elucidate possible molecular mechanisms underlying the effect of pioglitazone, a synthetic ligand for PPARgamma, on cell growth in these cell lines. RT-PCR and Western blot analysis showed that both human CRC cell lines expressed PPARgamma mRNA and protein. Pioglitazone inhibited the cell growth of both cell lines through G2/M phase block and apoptosis. In addition, pioglitazone caused a down-regulation of the X chromosome-linked inhibitor of apoptosis (XIAP), Bcl-2, and cyclooxygenase-2 (COX-2) under conditions leading to PPARgamma down-regulation. These results suggest that pioglitazone may have therapeutic relevance or significance in the treatment of human CRC, and the down-regulation of XIAP, Bcl-2, and COX-2 may contribute to pioglitazone-induced apoptosis in these and other RB-deficient cell lines and tumors.
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Abstract
A report on the 23rd Fungal Genetics Conference, Pacific Grove, USA, 15-20 March 2005. A report on the 23rd Fungal Genetics Conference, Pacific Grove, USA, 15-20 March 2005.
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Matrix attachment region from the chicken lysozyme locus reduces variability in transgene expression and confers copy number-dependence in transgenic rice plants. PLANT CELL REPORTS 2005; 24:145-54. [PMID: 15714322 DOI: 10.1007/s00299-005-0915-2] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/22/2004] [Revised: 12/18/2004] [Accepted: 12/22/2004] [Indexed: 05/23/2023]
Abstract
Matrix-attachment regions (MARs) may function as domain boundaries and partition chromosomes into independently regulated units. In this study, BP-MAR, a 1.3-kb upstream fragment of the 5'MAR flanking the chicken lysozyme locus, was tested for its effects on integration and expression of transgenes in transgenic rice plants. Using the Agrobacterium-mediated method, we transformed rice with nine different constructs containing seven and six different promoters and coding sequences, respectively. Genomic Southern blot analyses of 357 independent transgenic lines revealed that in the presence of BP-MAR, 57% of the lines contained a single copy of the transgene, whereas in its absence, only 20% of the lines contained a single copy of the transgene. RNA gel-blot and immunoblot experiments demonstrated that in the presence of BP-MAR, transgene expression levels were similar among different lines. These data were in direct contrast to those derived from transgenes expressed in the absence of BP-MAR, which varied markedly with the chromosomal integration site . Thus, it can be concluded that BP-MAR significantly reduces the variability in transgene expression between independent transformants. Moreover, the presence of BP-MAR appears to confer a copy number-dependent increase in transgene expression, although it does not increase expression levels of individual transgenes. These data contrast with results previously obtained with various MARs that increased expression levels of transgene significantly. Therefore, we conclude that the incorporation of BP-MAR sequences into the design of transformation vectors can minimize position effects and regulate transgene expression in a copy number-dependent way.
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Decision-Related Factors and Attitudes Toward Donation in Living Related Liver Transplantation: Ten-Year Experience. Transplant Proc 2005; 37:1081-4. [PMID: 15848629 DOI: 10.1016/j.transproceed.2005.01.032] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
INTRODUCTION Living related liver transplantation (LRLT) has been performed since 1994 in Korea; more than 600 donors have contributed to our successful LRLT program for 10 years. Although the decision to donate is difficult and the donors need a formal psychosocial assessment, no system has been available to us for the assessment. This survey was performed as a presurveillance for the development of a psychosocial assessment protocol. METHODS A survey questionnaire included 31 questions on general and medical characteristics, factors, and processes related to the decision for donation. Donors of partial livers at least 6 months ago during the period from December 1994 to August 2003 and whose address could be confirmed by telephone were enrolled in the study. RESULTS A questionnaire was sent by mail to 441 contactable donors of whom 209 (47.4%) responded. Male-to-female ratio was 2:1 and mean age was 32.8 years (range: 16 to 60 years). The number of spousal donors was 120 (57.4%) and 164 (78.5%) donors were employed at the time of donation. Protestants, Buddhists, and Catholics were 29.2%, 19.1%, and 14.8%, respectively. Parents were the most common recipients (33.0%), followed by siblings (17.2%), extended family members (17.2%), and children (15.8%); one hundred eighty nine (90.4%) donors had decided by themselves, the major reason for donation in 192 (91.9%) donors was "to save the lives of family members and relatives." The first person who suggested donation was the donor (64.1%), followed by family members (23.9%) or the attending physicians (8.6%). Although 70.8% of donors answered that they were not hesitant to donate at the time of decision, 44.5% were uneasy at the possibility of being unable to sustain a normal life after donation, at their lack of knowledge on organ donation, and about the pain and fear of surgery. Family members and relatives (53.3%), medical personnel (46.7%), and previous donors (35.4%) were the preferable counselors compared to transplantation institutions and clergymen. The large majority (80.8%) of donors would encourage others to donate. CONCLUSIONS Although the decision to donate was made by the donors themselves in most cases and they appeared firm and determined about their decision, a significant number of donors felt uneasy about possible complications of organ donation and effects on their lives after donation. A precise and formal psychosocial assessment protocol is needed to support and secure their decision before and after donation.
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Pulmonary vascular dilation induced by L-ARGININE: correlation with induction of endothelial nitric oxide synthase in a rabbit model. Acta Radiol 2005; 46:48-54. [PMID: 15841740 DOI: 10.1080/02841850510012607] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
PURPOSE To determine whether oral administration of L-ARGININE induces pulmonary vascular dilation, and if this pulmonary vascular dilation correlates with induction of endothelial nitric oxide synthase (eNOS) in a rabbit model. MATERIAL AND METHODS Seven rabbits were fed with L-ARGININE dissolved in tap water. The degree of pulmonary vascular dilation was determined using thin-section computed tomography and the concentration of serum nitrite was measured. They were compared with four control animals. The pulmonary vascular dilation was correlated to serum levels of nitrite. Lung tissues were examined for induction of eNOS by immunohistochemistry. RESULTS An increased degree of pulmonary vascular dilation was found in the L-ARGININE-fed group compared to the control group (P<0.05). Serum levels of nitrite in the L-ARGININE-fed group were higher than those in the control group (P<0.05). Pulmonary vascular dilation correlated with serum levels of nitrite (r2=0.95, P<0.05). Induction of eNOS was increased in the L-ARGININE-fed group. CONCLUSION The administration of L-ARGININE causes pulmonary vascular dilation, which is most likely mediated via nitric oxide through increased induction of eNOS in a rabbit model.
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The rice blast pathosystem as a case study for the development of new tools and raw materials for genome analysis of fungal plant pathogens. THE NEW PHYTOLOGIST 2003; 159:53-61. [PMID: 33873673 DOI: 10.1046/j.1469-8137.2003.00787.x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Fungi have an astounding and diverse impact on this planet. While they are agents of human diseases and the cause of allergic reactions, factories for the conversion of carbon in environmental and industrially adapted systems, and potential biological weapons, their importance as plant pathogens is unparalleled. In plants alone, fungi cause tens of thousands of different diseases and are responsible for massive losses of food, fiber and forestry at an estimated annual cost of hundreds of billions of dollars. These losses are not only realized in the incomes of individual farmers and state economies, but contribute significantly to world hunger problems and issues relating to safeguarding a global food supply. Our collective understanding of how fungi, particularly plant pathogens, grow, reproduce, identify a host and cause disease is still at a formative stage. There is an equal lack of detailed knowledge about how a plant recognizes that it is being attacked and then mounts an adequate defense response. The advent of genomic technologies has given researchers an unprecedented opportunity to address these mysteries in a powerful and more holistic manner. Where the genetic revolution of only a few years ago allowed for the characterization of single genes, today's genomic technologies are facilitating the evaluation of the entire complement of genes in an organism and the discovery of the suites of genes that act during any one time or particular condition. This review will describe the recent development of tools for whole or partial genome analysis and multigenome comparisons. Th discussion focuses on the rice blast pathosystem as a case study.
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An efficient motion estimation and compensation method for ultrasound synthetic aperture imaging. ULTRASONIC IMAGING 2002; 24:81-99. [PMID: 12199420 DOI: 10.1177/016173460202400202] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
This paper describes a method for overcoming motion artifacts in synthetic aperture imaging. The method is based on a computer simulation study on the influence of target motion on synthetic aperture techniques. A region-based motion compensation approach is used in which only the axial motion is estimated and compensated for a given region of interest under the assumption that the whole ROI moves uniformly. The estimated axial motion is calculated with a crosscorrelation method at the point where the focused signal has the maximum energy within the ROI. We also present a method for estimating axial motion using the autocorrelation method that is widely used to estimate average Doppler frequency. Both computer simulations and in vivo experiments show that the proposed crosscorrelation-based method can greatly improve the spatial resolution and SNR of ultrasound imaging by implementing SA techniques for two-way dynamic focusing without motion artifacts. In addition, the autocorrelation-based motion compensation method provides almost the same results as the crosscorrelation-based method, but with a dramatically reduced computational complexity.
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Characterization of inwardly rectifying K(+) conductance across the basolateral membrane of rat tracheal epithelia. Biochem Biophys Res Commun 2001; 288:914-20. [PMID: 11688996 DOI: 10.1006/bbrc.2001.5831] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
The rat primary cultured-airway monolayer has been an excellent model for deciphering the ion channel after nystatin permeabilization of its basolateral or apical membrane. Inwardly rectifying K(+) currents were characterized across the basolateral membrane in symmetrical HCO(-)(3)-free high K(+) Ringer's solution (125 mM) in this study. The potency of K(+) channel inhibitors against K(+) conductance was Ba(2+) (IC(50) = 5 microM) > Cs(+) (IC(50) = 2 mM) >> glybenclamide (IC(50) > 5 mM) >> TEA (IC(50) >> 100 mM). The application of basolateral Cs(+) changed K(+) conductance into an oscillating current, and its frequency (holding voltage = -100 mV) increased with increase in concentration of basolateral Cs(+) (0.05-5 mM) and in degree of hyperpolarization. Addition of basolateral Cs(+) blocked inward current strongly at -100 mV and hardly at all at -60 mV, giving a sharp curvature to the I-V relation of the IRK current. RT-PCR, Western blotting, and immunohistochemical analyses showed that Kir2.1 might be present in basolateral membrane of tracheal epithelia and plasma membrane of pulmonary alveolar cells.
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Involvement of p38 kinase in hydroxyurea-induced differentiation of K562 cells. CELL GROWTH & DIFFERENTIATION : THE MOLECULAR BIOLOGY JOURNAL OF THE AMERICAN ASSOCIATION FOR CANCER RESEARCH 2001; 12:481-6. [PMID: 11571231] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 04/17/2023]
Abstract
Hydroxyurea is a differentiation-inducing agent of human erythroleukemia K562 cells. However, the cellular mechanisms by which hydroxyurea exerts its effects on tumor cells, leading to the inhibition of cell growth and the induction of differentiation markers, are largely unknown. This study examined the role of different mitogen-activated protein kinase signal transduction pathways in hydroxyurea-induced erythroid differentiation of K562 cells. Using a panel of anti-extracellular signal-related kinase (ERK), c-Jun NH2-terminal kinase (JNK), and p38 phosphospecific antibodies, we demonstrated that phosphorylation of ERK and JNK is decreased after the treatment of cells with hydroxyurea, whereas phosphorylation of p38 is increased. Moreover, inhibition of ERK activity by PD98059 induced erythroid differentiation, and it acted synergistically with hydroxyurea on hemoglobin synthesis, whereas inhibition of p38 activity by SB203580 inhibited induction of hemoglobin production by hydroxyurea. These findings suggest that the activation of p38 kinase may play important roles in the signal transduction mechanisms of hydroxyurea leading to erythroid differentiation.
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Abstract
The term myxosarcoma is currently not used in standard classification for soft tissue tumors, but restricted to cardiac tumors. Primary cardiac myxosarcoma is a very rare disease and is difficult to differentiate from myxoma clinically and pathologically. We report a case of left atrial myxosarcoma with widespread systemic metastasis in a 21-yr-old male. The patient presented with sudden onset of intermittent dyspnea and orthopnea. Echocardiography showed a mobile, pedunculated tumor, 7.5x5x2 cm in size, at left atrium. Histologically, the excised tumor showed an amorphous finely fibrillar and mucinous stroma, in which irregular cords and clusters of lepidic cells and large stellate cells with plump vesicular nuclei resembled the usual type of cardiac myxoma were noted. And it showed focally cellular area with great nuclear pleomorphism and frequent mitoses. The patient received combination chemotherapy, peripheral blood stem cell collection transplantation and operations for systemic metastases in the brain, skeletal muscle and lung. He is alive at present 37 months after initial diagnosis and has no more new metastatic lesion.
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Abstract
Thioacetamide (TA) is converted into a hyperacetylating agent which causes hepatic necrosis, regeneration, cirrhosis and cancerous transformation. One of the most characteristic toxicities of TA in rat is observed with a 50 mg/kg per day which induces nucleolar enlargement different from that in regenerating liver. From TA-treated liver, the nucleoli were isolated and characterized for an altered nucleolar signal transduction system. Immunochemistry revealed that the poisoned nucleoli had increased levels of both nucleolus specific proteins (nucleophosmin and nucleolin) and various signal molecules (CK2, Erk1/2, p38, protein kinases A and C, and cyclin A). Using flow cytometry, the nucleoli were found to be in G2-arrested nuclei. Manifestation of the nucleolar enlargement could be readily observed using an ex vivo hepatocyte culture. There were two types of nucleolar enlargement. One was observed in normal hepatocytes with light density of enlarged nucleoli. The other was in TA-treated hepatocytes with dense and compact density of enlarged nucleoli, which contained a 3 to 5-fold higher nudeophosmin content than the control. In vitro induction of nucleolar enlargement with TA was possible. As soon as the hepatocytes anchored on a collagen coat, exogeneous TA (higher than 1 microg/mL) could induce dense and compact nucleoli. However, when an exogeneous drug was added after monolayer formation (1 day), no drug-induced nucleolar enlargement was observed.
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Multicenter surveillance study for nosocomial infections in major hospitals in Korea. Nosocomial Infection Surveillance Committee of the Korean Society for Nosocomial Infection Control. Am J Infect Control 2000; 28:454-8. [PMID: 11114615 DOI: 10.1067/mic.2000.107592] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
BACKGROUND The goals of a surveillance for nosocomial infections (NIs) are to observe the magnitude and characteristics of NIs and to plan and evaluate policies and guidelines of infection control. This study was designed to determine the rate and distribution of NIs and their causative pathogens in Korean hospitals. METHODS Prospective surveillance was performed at 15 acute care hospitals with more than 500 beds during a 3-month period from June to August 1996. The case-finding methods were laboratory-based surveillance for patients in the general wards and a direct review of medical charts done regularly for all the patients in the intensive care units. RESULTS A total of 3162 NIs were found among 85,547 discharged patients, with an overall nosocomial infection rate of 3.70 per 100 patients discharged. Urinary tract infections constituted 30.3% of all NIs. Other infections were pneumonias, 17.2%, surgical site infections, 15.5%, and primary bloodstream infections, 14.5%. The infection rate was the highest in neurosurgery (14.21), followed by neurology (8. 62) and ontology services (6.70). The infection rate in intensive care units was higher than it was in the general wards (10.74 vs 2. 57, P =.001). The commonly isolated organisms were Staphylococcus aureus (17.2%), Pseudomonas aeruginosa (13.8%), and Escherichia coli (12.3%). CONCLUSIONS This first multicenter surveillance study provided extensive information on the current status and trends of NIs in major hospitals in Korea. The results may contribute to the evaluation of infection control programs and the development of effective strategies in these hospitals.
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Hydroxyurea induces a senescence-like change of K562 human erythroleukemia cell. J Cancer Res Clin Oncol 2000; 126:455-60. [PMID: 10961388] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/17/2023]
Abstract
Hydroxyurea, a differentiation-inducing agent of human erythroleukemia K562 cells, is commonly used to treat some types of leukemia. However, the mechanism for its therapeutic effect is not clearly understood yet. In this study, we have observed an interesting effect of hydroxyurea on tumor cells: an induction of senescence-like changes. Human erythroleukemia K562 cells, when treated with hydroxyurea for 7 days or more, underwent a change into phenotypically senescent cells together with a reduction of hemoglobin generation, a differentiation marker. The hydroxyurea-treated cells showed positive senescence associated-beta-galactosidase staining, a senescence index, and the accumulation of cdk (cyclin dependent kinase) inhibitors, such as p16INK4a, p21Waf1, and p27Kip1, implicated in cellular senescence. Nonetheless, these changes were not accompanied by DNA fragmentation. Taken together, we summarize that the long-term treatment of cancer cells with hydroxyurea can induce cellular senescence different from differentiation or programmed cell death.
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Changes in expression of cell cycle regulators and their hepatic lobular distribution in partial hepatectomy-induced regenerating rat liver. J Korean Med Sci 1999; 14:635-42. [PMID: 10642941 PMCID: PMC3054434 DOI: 10.3346/jkms.1999.14.6.635] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/16/2023] Open
Abstract
Partial hepatectomy (PH) endorses quiescent hepatocytes to reenter the cell cycle. The regenerating liver returns to its preresection weight after 7 days, following one or two cell division and maintains nearly its original volume after then. We focused on the inhibition of further hepatocyte proliferation, hypothesizing possible involvement of cell cycle upregulators and inhibitors. We studied protein levels in expression of cyclins, cyclin dependent kinases (CDKs) and CDK inhibitors (CKIs), and their in situ hepatic lobular distributions in partial hepatectomized rat liver. Cyclin E was expressed in the same levels in normal liver and after PH. Expression of cyclin A, not detected in normal liver, increased in following times after PH and reached a maximum at 7 day. CDK2 and 4 showed increased expression toward terminal period. Contradictory findings of cyclin A and these CDKs might play an important role in the inhibition of further cell division, although still unclear. Constitutively expressed CDK6 decreased after 1 day. p18 showed peak expression within 1 day, and p16, p21, p27 and p57 were stronger at terminal periods. During the expected period of their activity, intranuclear translocations were observed in cyclin E, p18 and p16. There was no evidence of regional distribution in hepatic lobular architecture, instead, diffuse in situ expression, corroborating synchronous event, was found.
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Molecular cloning, expression, and functional characterization of a 2Cys-peroxiredoxin in Chinese cabbage. PLANT MOLECULAR BIOLOGY 1999; 40:825-834. [PMID: 10487217 DOI: 10.1023/a:1006271823973] [Citation(s) in RCA: 48] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
A cDNA (C2C-Prx) corresponding to a 2Cys-peroxiredoxin (2Cys-Prx) was isolated from a leaf cDNA library of Chinese cabbage. The predicted amino acid sequence of C2C-Prx has 2 conserved cysteines and several peptide domains present in most of the 2Cys-Prx subfamily members. It shows the highest sequence homology to the 2Cys-Prx enzymes of spinach (88%) and Arabidopsis (86%). Southern analysis using the cDNA insert of C2C-Prx revealed that it consists of a small multigene family in Chinese cabbage genome. RNA blot analysis showed that the gene was predominantly expressed in the leaf tissue of Chinese cabbage seedlings, but the mRNA was generally expressed in most tissues of mature plant, except roots. The expression of C2C-Prx was slightly induced by treatment with H2O2 (100 microM) or Fe3+/O2/DTT oxidation system, but not by ABA (50 microM) or GA3 (10 microM). The C2C-Prx is encoded as a preprotein of 273 amino acids containing a putative chloroplast-targeting signal of 65 amino acids at its N-terminus. The N-terminally truncated recombinant protein (deltaC2C-Prx) migrates as a dimer in a non-reducing SDS-polyacrylamide gel and as a monomer in a reducing condition. The deltaC2C-Prx shows no immuno cross-reactivity to antiserum of the yeast thiol-specific antioxidant protein, and vice versa. The deltaC2C-Prx prevents the inactivation of glutamine synthetase and the DNA cleavage in the metal-catalyzed oxidation system. In the yeast thioredoxin system containing thioredoxin reductase, thioredoxin, and NADPH, the deltaC2C-Prx exhibits peroxidase activity on H2O2.
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Purification and characterization of a second type thioredoxin peroxidase (type II TPx) from Saccharomyces cerevisiae. Biochemistry 1999; 38:776-83. [PMID: 9888818 DOI: 10.1021/bi9817818] [Citation(s) in RCA: 97] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
A yeast peroxidase that reduces H2O2 and alkyl hydroperoxides with the use of reducing equivalents provided by thioredoxin was identified previously and named thioredoxin peroxidase (TPx) [Chae, H. Z., Chung, S. J., and Rhee, S. G. (1994) J. Biol. Chem. 269, 27670-27678]. A second type thioredoxin-dependent peroxidase, named type II TPx, has now been purified from yeast, and several peptide sequences have been obtained. Using those sequences, the corresponding cDNA has been identified from the GenBank database. Comparison of the predicted sequence of 176 amino acids of type II TPx with that of the 195 residues of TPx, now renamed type I TPx, revealed no substantial homology except for a short segment preceding Cys62 of type II TPx. Kinetic characterization of the reactions catalyzed by type I and II TPxs revealed that type I preferentially reduces H2O2 rather than alkyl hydroperoxides, whereas type II shows the reverse specificity. Type II TPx contains three cysteine residues at positions 31, 62, and 120. Experiments with mutant proteins in which these three cysteine residues were replaced individually with serine suggest that Cys62-SH constitutes the site of oxidation by peroxides and that the oxidized Cys62 reacts with the Cys120-SH group of another type II TPx molecule to form an intermolecular disulfide linkage. The formed disulfide can then be reduced by thioredoxin, but not by glutathione. Thus, type II TPx mutants lacking Cys62 or Cys120 showed no detectable TPx activity, whereas mutation of Cys31 had no effect on TPx activity. An antioxidant function of type II TPx in intact cells was demonstrated by the observation that Escherichia coli cells overexpressing wild-type protein were less sensitive to inhibition of growth by alkyl hydroperoxides than were control cells or cells overexpressing the mutant protein lacking Cys62.
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Nucleolus contains signal molecules that constitute membrane-nucleolus linked pathway. Exp Mol Med 1998; 30:205-13. [PMID: 9894150 DOI: 10.1038/emm.1998.30] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
Since there have been very few studies on nucleolar signaling, an attempt was made to establish nucleolar signal pathways which link the cell membrane to the nucleolus for the transfer of extracellular signals. Two pathways were studied. One was the G alpha s mediated cAMP pathway where two signal molecules were yielded, including RII and protein kinase A. The other was the G alpha q mediated DAG/IP3 pathway which yields two signals including protein kinase C and IP3/Ca2+. By the studying isolated nucleoli from resting liver, regenerating liver or weak carcinogen thioacetamide treated liver, it was possible to detect protein kinase A (PKA), protein kinase C (PKC) and RII subunits. In addition, CK2 was detected. It was found that external signals transmitted through G protein coupled receptors could reach into the nucleolus and that physical translocation of signal molecules was an integral step involved in membrane-nucleolus linked pathways. When an in vitro assay of the above signal molecules was carried out using [gamma-32P]-ATP, most kinase dependent phosphorylation was via the major CK2 (more than 95%). Therefore, it is suggested that the major CK2 dependent pathway is involved in 'house keeping' for nucleolar integrity and the minor pathways, dependent on PKA, PKC and others, are involved in subtle regulatory mechanisms such as 'extra-house-keeping' activities by nucleolar chromosomal remodeling.
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The RIIbeta regulatory subunit of protein kinase A binds to cAMP response element: an alternative cAMP signaling pathway. Proc Natl Acad Sci U S A 1998; 95:6687-92. [PMID: 9618473 PMCID: PMC22599 DOI: 10.1073/pnas.95.12.6687] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
cAMP, through the activation of cAMP-dependent protein kinase (PKA), is involved in transcriptional regulation. In eukaryotic cells, cAMP is not considered to alter the binding affinity of CREB/ATF to cAMP-responsive element (CRE) but to induce serine phosphorylation and consequent increase in transcriptional activity. In contrast, in prokaryotic cells, cAMP enhances the DNA binding of the catabolite repressor protein to regulate the transcription of several operons. The structural similarity of the cAMP binding sites in catabolite repressor protein and regulatory subunit of PKA type II (RII) suggested the possibility of a similar role for RII in eukaryotic gene regulation. Herein we report that RIIbeta subunit of PKA is a transcription factor capable of interacting physically and functionally with a CRE. In contrast to CREB/ATF, the binding of RIIbeta to a CRE was enhanced by cAMP, and in addition, RIIbeta exhibited transcriptional activity as a Gal4-RIIbeta fusion protein. These experiments identify RIIbeta as a component of an alternative pathway for regulation of CRE-directed transcription in eukaryotic cells.
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Beam-array combination with planar integrated optics for three-dimensional multistage interconnection networks. APPLIED OPTICS 1997; 36:5728-5731. [PMID: 18259399 DOI: 10.1364/ao.36.005728] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
We propose a configuration of planar integrated optics for three-dimensional multistage interconnection networks. To show the feasibility of cascading operations in the planar integrated optics, we present experimental results on the beam combination of signal- and power-beam arrays at a node stage. The beam-combination efficiency measured in the experiment is ~42% of the theoretical limit.
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Optical polarization switching in a Fabry-Perot étalon that utilizes the photoinduced Kerr effect. APPLIED OPTICS 1994; 33:3189-3191. [PMID: 20885686 DOI: 10.1364/ao.33.003189] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
We present an all-optical polarization switching of an asymmetric Fabry-Perot étalon containing a nonlinear Kerr medium in reflection type. Reflectance of a signal wave breaks up into two orthogonal polarization components as a result of photoinduced birefringent effects and shows distinct features of intensity stability and a high extinction ratio in polarization switching-modulation and memory operations.
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