Mycobacterium smegmatis Ku binds DNA without free ends.

Science.gov (United States)

Kushwaha, Ambuj K; Grove, Anne

2013-12-01

Ku is central to the non-homologous end-joining pathway of double-strand-break repair in all three major domains of life, with eukaryotic homologues being associated with more diversified roles compared with prokaryotic and archaeal homologues. Ku has a conserved central 'ring-shaped' core domain. While prokaryotic homologues lack the N- and C-terminal domains that impart functional diversity to eukaryotic Ku, analyses of Ku from certain prokaryotes such as Pseudomonas aeruginosa and Mycobacterium smegmatis have revealed the presence of distinct C-terminal extensions that modulate DNA-binding properties. We report in the present paper that the lysine-rich C-terminal extension of M. smegmatis Ku contacts the core protein domain as evidenced by an increase in DNA-binding affinity and a decrease in thermal stability and intrinsic tryptophan fluorescence upon its deletion. Ku deleted for this C-terminus requires free DNA ends for binding, but translocates to internal DNA sites. In contrast, full-length Ku can directly bind DNA without free ends, suggesting that this property is conferred by its C-terminus. Such binding to internal DNA sites may facilitate recruitment to sites of DNA damage. The results of the present study also suggest that extensions beyond the shared core domain may have independently evolved to expand Ku function.

Ku80-deleted cells are defective at base excision repair

International Nuclear Information System (INIS)

Li, Han; Marple, Teresa; Hasty, Paul

2013-01-01

Graphical abstract: - Highlights: • Ku80-deleted cells are hypersensitive to ROS and alkylating agents. • Cells deleted for Ku80, but not Ku70 or Lig4, have reduced BER capacity. • OGG1 rescues hypersensitivity to H 2 O 2 and paraquat in Ku80-mutant cells. • Cells deleted for Ku80, but not Lig4, are defective at repairing AP sites. • Cells deleted for Ku80, but not Lig4 or Brca2 exon 27, exhibit increased PAR. - Abstract: Ku80 forms a heterodimer with Ku70, called Ku, that repairs DNA double-strand breaks (DSBs) via the nonhomologous end joining (NHEJ) pathway. As a consequence of deleting NHEJ, Ku80-mutant cells are hypersensitive to agents that cause DNA DSBs like ionizing radiation. Here we show that Ku80 deletion also decreased resistance to ROS and alkylating agents that typically cause base lesions and single-strand breaks (SSBs). This is unusual since base excision repair (BER), not NHEJ, typically repairs these types of lesions. However, we show that deletion of another NHEJ protein, DNA ligase IV (Lig4), did not cause hypersensitivity to these agents. In addition, the ROS and alkylating agents did not induce γ-H2AX foci that are diagnostic of DSBs. Furthermore, deletion of Ku80, but not Lig4 or Ku70, reduced BER capacity. Ku80 deletion also impaired BER at the initial lesion recognition/strand scission step; thus, involvement of a DSB is unlikely. Therefore, our data suggests that Ku80 deletion impairs BER via a mechanism that does not repair DSBs

Ku80-deleted cells are defective at base excision repair

Energy Technology Data Exchange (ETDEWEB)

Li, Han [The University of Texas Health Science Center at San Antonio, The Institute of Biotechnology, The Department of Molecular Medicine, 15355 Lambda Drive, San Antonio, TX 78245-3207 (United States); Tumor Suppression Group, Spanish National Cancer Research Centre (CNIO), Madrid 28029 (Spain); Marple, Teresa [The University of Texas Health Science Center at San Antonio, The Institute of Biotechnology, The Department of Molecular Medicine, 15355 Lambda Drive, San Antonio, TX 78245-3207 (United States); Hasty, Paul, E-mail: hastye@uthscsa.edu [The University of Texas Health Science Center at San Antonio, The Institute of Biotechnology, The Department of Molecular Medicine, 15355 Lambda Drive, San Antonio, TX 78245-3207 (United States); Tumor Suppression Group, Spanish National Cancer Research Centre (CNIO), Madrid 28029 (Spain)

2013-05-15

Graphical abstract: - Highlights: • Ku80-deleted cells are hypersensitive to ROS and alkylating agents. • Cells deleted for Ku80, but not Ku70 or Lig4, have reduced BER capacity. • OGG1 rescues hypersensitivity to H{sub 2}O{sub 2} and paraquat in Ku80-mutant cells. • Cells deleted for Ku80, but not Lig4, are defective at repairing AP sites. • Cells deleted for Ku80, but not Lig4 or Brca2 exon 27, exhibit increased PAR. - Abstract: Ku80 forms a heterodimer with Ku70, called Ku, that repairs DNA double-strand breaks (DSBs) via the nonhomologous end joining (NHEJ) pathway. As a consequence of deleting NHEJ, Ku80-mutant cells are hypersensitive to agents that cause DNA DSBs like ionizing radiation. Here we show that Ku80 deletion also decreased resistance to ROS and alkylating agents that typically cause base lesions and single-strand breaks (SSBs). This is unusual since base excision repair (BER), not NHEJ, typically repairs these types of lesions. However, we show that deletion of another NHEJ protein, DNA ligase IV (Lig4), did not cause hypersensitivity to these agents. In addition, the ROS and alkylating agents did not induce γ-H2AX foci that are diagnostic of DSBs. Furthermore, deletion of Ku80, but not Lig4 or Ku70, reduced BER capacity. Ku80 deletion also impaired BER at the initial lesion recognition/strand scission step; thus, involvement of a DSB is unlikely. Therefore, our data suggests that Ku80 deletion impairs BER via a mechanism that does not repair DSBs.

A moonlighting function of Mycobacterium smegmatis Ku in zinc homeostasis?

Science.gov (United States)

Kushwaha, Ambuj K; Deochand, Dinesh K; Grove, Anne

2015-02-01

Ku protein participates in DNA double-strand break repair via the nonhomologous end-joining pathway. The three-dimensional structure of eukaryotic Ku reveals a central core consisting of a β-barrel domain and pillar and bridge regions that combine to form a ring-like structure that encircles DNA. Homologs of Ku are encoded by a subset of bacterial species, and they are predicted to conserve this core domain. In addition, the bridge region of Ku from some bacteria is predicted from homology modeling and sequence analyses to contain a conventional HxxC and CxxC (where x is any residue) zinc-binding motif. These potential zinc-binding sites have either deteriorated or been entirely lost in Ku from other organisms. Using an in vitro metal binding assay, we show that Mycobacterium smegmatis Ku binds two zinc ions. Zinc binding modestly stabilizes the Ku protein (by ∼3°C) and prevents cysteine oxidation, but it has little effect on DNA binding. In vivo, zinc induces significant upregulation of the gene encoding Ku (∼sixfold) as well as a divergently oriented gene encoding a predicted zinc-dependent MarR family transcription factor. Notably, overexpression of Ku confers zinc tolerance on Escherichia coli. We speculate that zinc-binding sites in Ku proteins from M. smegmatis and other mycobacterial species have been evolutionarily retained to provide protection against zinc toxicity without compromising the function of Ku in DNA double-strand break repair. © 2014 The Protein Society.

Regulation of homologous recombination repair protein Rad51 by Ku70

International Nuclear Information System (INIS)

Du Liqing; Liu Qiang; Wang Yan; Xu Chang; Cao Jia; Fu Yue; Chen Fenghua; Fan Feiyue

2013-01-01

Objective: To explore the regulative effect of non-homologous end joining (NHEJ)protein Ku70 on homologous recombination repair protein Rad51, and to investigate the synergistic mechanism of homologous recombination repair in combination with NHEJ. Methods: Observed Rad51 protein expression after transfect Ku70 small interfering RNA or Ku70 plasmid DNA into tumor cells using Western blot. Results: Expression of Rad51 was obviously reduced after pretreated with Ku70 small interfering RNA. And with the increasing expression of Ku70 protein after transfection of Ku70 plasmid DNA PGCsi3.0-hKu70 into tumor cell lines, the Rad51 protein expression was increased. Conclusion: Ku70 protein has regulating effect on gene expression of Rad51, and it might participate in the collaboration between homologous recombination repair and NHEJ. (authors)

Kuş Gölü (Bandırma Makrobentik Omurgasız Faunası Hakkında Bir Ön Araştırma.

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Süleyman Balık

2015-12-01

Full Text Available Kuş Gölü’nün makrobentik omurgasız faunasını belirlemek amacıyla 1987 ve 1988 yılları arasında aylık periyotlar halinde, bir yıl süre ile 5 istasyonda arazi çalışması yapılmıştır. Ekman grab ile alınan çamur örnekleri 500 μm göz açıklığındaki elekten geçirilmiş ve örnekler %4’lük formaldehit solüsyonunda tespit edilmiştir. Araştırma sonucunda, Oligochaeta sınıfından 10, Chironomidae familyasından 5 ve Ceratopogonidae familyasından 1 olmak üzere toplam 16 takson tespit edilmiştir. Kuş gölü’nde metrekarede ortalama 6759 birey tespit edilmiş, grupların oransal dağılımında %81,94 ile Oligochaeta bireylerinin en baskın grubu oluşturduğu, bu grubu Chironomidae (%17,90 ve Ceratopogonidae (%0,16 larvalarının takip ettiği saptanmıştır. Tespit edilen grupların istasyonlara göre oransal dağılımlarında ise, 1. istasyonun en zengin (%28,71, 4. istasyonun en fakir (%12,77 istasyon olduğu gözlenmiştir

Gode råd til KU om bæredygtig omstilling

DEFF Research Database (Denmark)

Lund, Jens Friis

2016-01-01

I gennemsnit flyver alle KU-ansatte retur til Cairo årligt. KU's stigende internationalisering skader klimaet, og det kræver bæredygtig omstilling.......I gennemsnit flyver alle KU-ansatte retur til Cairo årligt. KU's stigende internationalisering skader klimaet, og det kræver bæredygtig omstilling....

Interaction of caveolin-1 with Ku70 inhibits Bax-mediated apoptosis.

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Huafei Zou

Full Text Available Caveolin-1, the structural protein component of caveolae, acts as a scaffolding protein that functionally regulates signaling molecules. We show that knockdown of caveolin-1 protein expression enhances chemotherapeutic drug-induced apoptosis and inhibits long-term survival of colon cancer cells. In vitro studies demonstrate that caveolin-1 is a novel Ku70-binding protein, as shown by the binding of the scaffolding domain of caveolin-1 (amino acids 82-101 to the caveolin-binding domain (CBD of Ku70 (amino acids 471-478. Cell culture data show that caveolin-1 binds Ku70 after treatment with chemotherapeutic drugs. Mechanistically, we found that binding of caveolin-1 to Ku70 inhibits the chemotherapeutic drug-induced release of Bax from Ku70, activation of Bax, translocation of Bax to mitochondria and apoptosis. Potentiation of apoptosis by knockdown of caveolin-1 protein expression is greatly reduced in the absence of Bax expression. Finally, we found that overexpression of wild type Ku70, but not a mutant form of Ku70 that cannot bind to caveolin-1 (Ku70 Φ→A, limits the chemotherapeutic drug-induced Ku70/Bax dissociation and apoptosis. Thus, caveolin-1 acts as an anti-apoptotic protein in colon cancer cells by binding to Ku70 and inhibiting Bax-dependent cell death.

Ku70 inhibits gemcitabine-induced DNA damage and pancreatic cancer cell apoptosis

International Nuclear Information System (INIS)

Ma, Jiali; Hui, Pingping; Meng, Wenying; Wang, Na; Xiang, Shihao

2017-01-01

The current study focused on the role of Ku70, a DNA-dependent protein kinase (DNA-PK) complex protein, in pancreatic cancer cell resistance to gemcitabine. In both established cell lines (Mia-PaCa-2 and PANC-1) and primary human pancreatic cancer cells, shRNA/siRNA-mediated knockdown of Ku70 significantly sensitized gemcitabine-induced cell death and proliferation inhibition. Meanwhile, gemcitabine-induced DNA damage and subsequent pancreatic cancer cell apoptosis were also potentiated with Ku70 knockdown. On the other hand, exogenous overexpression of Ku70 in Mia-PaCa-2 cells suppressed gemcitabine-induced DNA damage and subsequent cell apoptosis. In a severe combined immune deficient (SCID) mice Mia-PaCa-2 xenograft model, gemcitabine-induced anti-tumor activity was remarkably pontificated when combined with Ku70 shRNA knockdown in the xenografts. The results of this preclinical study imply that Ku70 might be a primary resistance factor of gemcitabine, and Ku70 silence could significantly chemo-sensitize gemcitabine in pancreatic cancer cells. - Highlights: • Ku70 knockdown sensitizes gemcitabine-induced killing of pancreatic cancer cells. • Ku70 knockdown facilitates gemcitabine-induced DNA damage and cell apoptosis. • Ku70 overexpression deceases gemcitabine's sensitivity in pancreatic cancer cells. • Ku70 knockdown sensitizes gemcitabine-induced anti-tumor activity in vivo.

Styl radzenia sobie ze stresem jako moderator związku lęku z neurotyzmem u osób z reumatoidalnym zapaleniem stawów

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Michał Ziarko

2011-06-01

Full Text Available Lęk stanowi jedną z konsekwencji chorób przewlekłych, w tymreumatoidalnego zapalenia stawów (RZS. Wysoki poziom lękuobniża jakość życia pacjentów, prowadzi do zachowań antyzdrowotnychoraz może wpływać na gorszy przebieg choroby. Związekneurotyzmu z lękiem został dotąd dobrze udokumentowany. Neurotyzmstanowi cechę temperamentu, a więc w niewielkim stopniumożna ją modyfikować. Redukcja kosztów psychicznych ponoszonychprzez osoby o wysokim poziomie neurotyzmu wymagapoznania czynników, które mogłyby ograniczać wpływ neurotyzmuna poziom lęku (czynniki moderujące relację neurotyzm–lęk.Celem badania było określenie zmiennych moderujących relacjępomiędzy neurotyzmem a lękiem.W badaniach wzięło udział 100 osób chorujących na RZS (78 ko -biet i 22 mężczyzn. Zostali oni przebadani za pomocą kwestionariuszymierzących: poziom lęku, style radzenia sobie ze stresemoraz wymiary osobowości. Obliczono współczynniki korelacjir Pearsona pomiędzy mierzonymi zmiennymi oraz wykonano analizęmoderacji związku pomiędzy neurotyzmem a lękiem jakostanem za pośrednictwem stylów radzenia sobie ze stresem.Testowanie interakcji przeprowadzono metodą najmniejszych kwadratówi regresji logistycznej.Ustalono, że istnieje wprost proporcjonalny związek pomiędzyneurotyzmem a lękiem rozumianym jako stan (r = 0,63; p < 0,01(tab. I. Zaobserwowano, że związek ten nie zachodzi w przypadkuosób o wysokim neurotyzmie posługujących się unikowym stylem radzenia sobie ze stresem (R2 = 0,19; F = 7,00; p < 0,001 (ryc. 1oraz u osób poszukujących kontaktów towarzyskich (R2 = 0,22;F = 8,70; p < 0,001 (ryc. 2, tab. II.Wyniki wskazują, że silny neurotyzm zwiększa prawdopodobieństworeagowania podwyższonym poziomem lęku w obliczu pojawiającychsię objawów oraz zagrożeń będących konsekwencjąchoroby. Zaobserwowane zależności potwierdzają hipotezę, żetemperament jest czynnikiem ryzyka w rozwoju zaburze

Ku70, Ku80, and sClusterin: A Cluster of Predicting Factors for Response to Neoadjuvant Chemoradiation Therapy in Patients With Locally Advanced Rectal Cancer

International Nuclear Information System (INIS)

Pucci, Sabina; Polidoro, Chiara; Joubert, Alessandro; Mastrangeli, Francesca; Tolu, Barbara; Benassi, Michaela; Fiaschetti, Valeria; Greco, Laura; Miceli, Roberto; Floris, Roberto; Novelli, Giuseppe; Orlandi, Augusto; Santoni, Riccardo

2017-01-01

Purpose: The identification of predictive biomarkers for neoadjuvant chemoradiation therapy (CRT) is a current clinical need. The heterodimer Ku70/80 plays a critical role in DNA repair and cell death induction after damage. The aberrant expression and localization of these proteins fail to control DNA repair and apoptosis. sClusterin is the Ku70 partner that sterically inhibits Bax-dependent cell death after damage in some pathologic conditions. This study sought to evaluate the molecular relevance of Ku70-Ku80-Clu as a molecular cluster predicting the response to neoadjuvant CRT in patients with locally advanced rectal cancer (LARC). Methods and Materials: Patients enrolled in this study underwent preoperative CRT followed by surgical excision. A retrospective study based on individual response, evaluated by computed tomography and diffusion-weighted magnetic resonance imaging, identified responder (56%) and no-responder patients (44%). Ku70/80 and Clu expression were observed in biopsy specimens obtained before and after treatment with neoadjuvant CRT from the same LARC patients. In vitro studies before and after irradiation were also performed on radioresistant (SW480) and radiosensitive (SW620) colorectal cancer cell lines, mimicking sensitive or resistant tumor behavior. Results: We found a conventional nuclear localization of Ku70/80 in pretherapeutic tumor biopsies of responder patients, in agreement with their role in DNA repair and regulating apoptosis. By contrast, in the no-responder population we observed an unconventional overexpression of Ku70 in the cytoplasm (P<.001). In this context we also overexpression of sClu in the cytoplasm, which accorded with its role in stabilizing of Bax-Ku70 complex, inhibiting Bax-dependent apoptosis. Strikingly, Ku80 in these tumor tissues was lost (P<.005). In vitro testing of colon cancer cells finally confirmed the results observed in tumor biopsy specimens, proving that Ku70/80-Clu deregulation is extensively

Ku70, Ku80, and sClusterin: A Cluster of Predicting Factors for Response to Neoadjuvant Chemoradiation Therapy in Patients With Locally Advanced Rectal Cancer

Energy Technology Data Exchange (ETDEWEB)

Pucci, Sabina, E-mail: sabina.pucci@uniroma2.it; Polidoro, Chiara; Joubert, Alessandro; Mastrangeli, Francesca; Tolu, Barbara; Benassi, Michaela; Fiaschetti, Valeria; Greco, Laura; Miceli, Roberto; Floris, Roberto; Novelli, Giuseppe; Orlandi, Augusto; Santoni, Riccardo

2017-02-01

Purpose: The identification of predictive biomarkers for neoadjuvant chemoradiation therapy (CRT) is a current clinical need. The heterodimer Ku70/80 plays a critical role in DNA repair and cell death induction after damage. The aberrant expression and localization of these proteins fail to control DNA repair and apoptosis. sClusterin is the Ku70 partner that sterically inhibits Bax-dependent cell death after damage in some pathologic conditions. This study sought to evaluate the molecular relevance of Ku70-Ku80-Clu as a molecular cluster predicting the response to neoadjuvant CRT in patients with locally advanced rectal cancer (LARC). Methods and Materials: Patients enrolled in this study underwent preoperative CRT followed by surgical excision. A retrospective study based on individual response, evaluated by computed tomography and diffusion-weighted magnetic resonance imaging, identified responder (56%) and no-responder patients (44%). Ku70/80 and Clu expression were observed in biopsy specimens obtained before and after treatment with neoadjuvant CRT from the same LARC patients. In vitro studies before and after irradiation were also performed on radioresistant (SW480) and radiosensitive (SW620) colorectal cancer cell lines, mimicking sensitive or resistant tumor behavior. Results: We found a conventional nuclear localization of Ku70/80 in pretherapeutic tumor biopsies of responder patients, in agreement with their role in DNA repair and regulating apoptosis. By contrast, in the no-responder population we observed an unconventional overexpression of Ku70 in the cytoplasm (P<.001). In this context we also overexpression of sClu in the cytoplasm, which accorded with its role in stabilizing of Bax-Ku70 complex, inhibiting Bax-dependent apoptosis. Strikingly, Ku80 in these tumor tissues was lost (P<.005). In vitro testing of colon cancer cells finally confirmed the results observed in tumor biopsy specimens, proving that Ku70/80-Clu deregulation is extensively

Discovery and characterization of Ku acetylation in Mycobacterium smegmatis.

Science.gov (United States)

Zhou, Ying; Chen, Tao; Zhou, Lin; Fleming, Joy; Deng, Jiaoyu; Wang, Xude; Wang, Liwei; Wang, Yingying; Zhang, Xiaoli; Wei, Wenjing; Bi, Lijun

2015-03-01

Lysine acetylation is an important post-translational modification and is known to regulate many eukaryotic cellular processes. Little, however, is known about acetylated proteins in prokaryotes. Here, using immunoblotting, mass spectrometry and mutagenesis studies, we investigate the acetylation dynamics of the DNA repair protein Ku and its relationship with the deacetylase protein Sir2 and the non-homologous end joining (NHEJ) pathway in Mycobacterium smegmatis. We report that acetylation of Ku increases with growth, while NHEJ activity decreases, providing support for the hypothesis that acetylation of Ku may be involved in the DNA damage response in bacteria. Ku has multiple lysine sites. Our results indicate that K29 is an important acetylation site and that deficiency of Sir2 or mutation of K29 affects the quantity of Ku and its acetylation dynamics. Our findings expand knowledge of acetylation targets in prokaryotes and indicate a new direction for further research on bacterial DNA repair mechanisms. © FEMS 2014. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

The Effect of the Unique Features of Y Generation on Organizational Commitment / Y Kuşağının Belirleyici Özelliklerinin Örgütsel Bağlılık Üzerindeki Etkisi

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Mustafa Emre Civelek

2017-12-01

Full Text Available ABSTRACT In this research, the determinants of the generations and unique characteristics of Generation Y are examined and the effect of this unique characteristics on organizational commitment is investigated. In the introduction part of the research, different features separating the generations from each other were mentioned and the studies done in this subject were examined and the studies and findings of different researchers were evaluated. In the final part of the survey, there is the analysis result of the survey collected from overall Turkey from 8 corporations. Sample size of this research is 267.  In order to measure organizational commitment, the scale developed by Allen and Meyer was used (Allen & Meyer, 1993. In order to measure team working, the scale developed by Levi and Slem was used (Levi & Slem, 1995. In order to measure playful spirit at work, the scale developed by Berg was used (Berg, 2011. According to the test results, there is a positive and significant relationship between Workplace fun and Team Working and between Team Working and Organizational Commitment. Contrary to expectation, there is not directly relation between organizational commitment and workplace fun. But work place fun positively effects organizational commitment through team working indirectly. The results of this research are to confirm that employees will be more likely to work in teams if organization environments are established to make them happy and entertained, thereby increasing their organizational commitment. ÖZ Bu araştırmada Kuşakların belirleyici özellikleri incelenerek Y kuşağını diğer kuşaklardan ayıran özelliklerin neler olduğu ve bu özelliklerin örgütsel bağlılık üzerinde ne gibi bir etkisi olduğu araştırılmaktadır. Araştırmanın giriş kısmında kuşakları birbirinden ayrıştıran farklı özelliklere değinilmiş ve bu konuda yapılan çalışmalar incelenerek farklı araştırmacıların �

Serum anti-Ku86 is a potential biomarker for early detection of hepatitis C virus-related hepatocellular carcinoma

Energy Technology Data Exchange (ETDEWEB)

Nomura, Fumio, E-mail: fnomura@faculty.chiba-u.jp [Department of Molecular Diagnosis, Graduate School of Medicine, Chiba University and Divisions of Laboratory Medicine, Clinical Genetics and Proteomics, Chiba University Hospital, Chiba (Japan); Sogawa, Kazuyuki; Noda, Kenta; Seimiya, Masanori; Matsushita, Kazuyuki; Miura, Toshihide [Department of Molecular Diagnosis, Graduate School of Medicine, Chiba University and Divisions of Laboratory Medicine, Clinical Genetics and Proteomics, Chiba University Hospital, Chiba (Japan); Tomonaga, Takeshi [Laboratory of Proteome Research, National Institute of Biomedical Innovation, Ibaraki (Japan); Yoshitomi, Hideyuki [Department of General Surgery, Graduate School of Medicine, Chiba University, Chiba (Japan); Imazeki, Fumio [Department of Medicine and Clinical Oncology, Graduate School of Medicine, Chiba University, Chiba (Japan); Takizawa, Hirotaka [Kashiwado Clinic in Port-Square of the Kashiwado Memorial Foundation, Chiba (Japan); Mogushi, Kaoru [Information Center for Medical Sciences, Tokyo Dental and Medical University, Tokyo (Japan); Miyazaki, Masaru [Department of General Surgery, Graduate School of Medicine, Chiba University, Chiba (Japan); Yokosuka, Osamu [Department of Medicine and Clinical Oncology, Graduate School of Medicine, Chiba University, Chiba (Japan)

2012-05-18

Highlights: Black-Right-Pointing-Pointer Overexpression of Ku86 in human liver cancer was shown by immunohistochemistry. Black-Right-Pointing-Pointer Serum anti-Ku86 was significantly elevated in early hepatocellular carcinoma. Black-Right-Pointing-Pointer Anti-Ku86 may be more sensitive than the conventional markers for early detection. Black-Right-Pointing-Pointer Serum anti-Ku86 significantly decreased after surgical resection of liver tumors. Black-Right-Pointing-Pointer Elevation of serum anti-Ku86 in other non-liver solid tumors was minimal. -- Abstract: Hepatocellular carcinoma (HCC), the predominant form of primary liver cancer, is one of the most common cancers worldwide and the third most common cause of cancer-related death. Imaging studies including ultrasound and computed tomography are recommended for early detection of HCC, but they are operator dependent, costly and involve radiation. Therefore, there is a need for simple and sensitive serum markers for the early detection of hepatocellular carcinoma (HCC). In our recent proteomic studies, a number of proteins overexpressed in HCC tissues were identified. We thought if the serum autoantibodies to these overexpressed proteins were detectable in HCC patients. Of these proteins, we focused on Ku86, a nuclear protein involved in multiple biological processes and aimed to assess the diagnostic value of serum anti-Ku86 in the early detection of HCC. Serum samples were obtained prior to treatment from 58 consecutive patients with early or relatively early hepatitis C virus (HCV)-related HCC and 137 patients with HCV-related liver cirrhosis without evidence of HCC. Enzyme immunoassays were used to measure serum levels of autoantibodies. Serum levels of anti-Ku86 antibodies were significantly elevated in HCC patients compared to those in liver cirrhosis patients (0.41 {+-} 0.28 vs. 0.18 {+-} 0.08 Abs at 450 nm, P < 0001). Setting the cut-off level to give 90% specificity, anti-Ku86 was positive in 60.7% of

Interspecific variation of intracellular localization and postirradiation movement of Ku70-protein in fibroblastic cells

International Nuclear Information System (INIS)

Endoh, Daiji; Hayashi, Masanobu; Okui, Toyo; Kawase, Shiro; Kon, Yasushiro

2003-01-01

Ku (Ku70 and Ku80) Proteins are known as components of DNA-dependent protein kinase (DNA-PK) and play an important role for DNA repair. We previously reported that more than 70% of Ku proteins were located in cytoplasm of rat cells, the Ku proteins moved into nuclei of normal rat cells after X-irradiation, Ku proteins also moved into nuclei after X-irradiation but were not retained in nucleus of radiosensitive LEC rat cells. While reports have been shown about mechanisms on nuclear localization of Ku proteins, how Ku proteins export from nucleus is poorly understood. Here we show that C-terminal region of Ku70 protein is important for its cytoplasmic localization. When transfected into LEC rat cells, exogenous intact Ku70 (1-609) tagged with enhanced green fluorescent protein (EGFP-Ku70) localized mainly in the cytoplasm, whereas C-terminal-deletion mutant of Ku70 (1-593) tagged with EGFP (EGFP-Ku70D) was mainly localized in the nucleus. After X-irradiation, the endogenous intact EGFP-Ku70 once moved into nucleus, but returned into the cytoplasm. On the other hand, EGFP-Ku70D was retained in nucleus for two hours after X-irradiation. These results suggest that C-terminal region of Ku70 is included in the postirradiation nuclear export. Next, we investigated the intracellular localization of Ku70 proteins and the movement after X-irradiation of fibroblastic cells prepared from some mammalian species. Ku70 proteins were localized in nucleus and the postirradiation-extranuclear transport was not observed in human and African green monkey cells. On the other hand, Ku70 proteins were mainly localized in cytoplasm and moved into nucleus in mouse, Chinese hamster, Golden hamster, cotton rat, squirrel, cat and dog cells. These results may show that alternatively Ku70 protein is localized in the cytoplasm or nucleus depends on species and translocation of cytoplasmic Ku70 into nucleus is a response against low dose irradiation in fibroblasts of rodents, cats and dogs

Hemşirelerin Bireysel ve Profesyonel Değerlerinde Kuşaklararası Farklılıklar / Personal and Professional Difference between the Generation of Nurses

OpenAIRE

IŞIK, Gülşen; EĞELİOĞLU CETİŞLİ, Nuray; TOKEM, Yasemin; YILMAZ, Dilan; İLHAN, Aylin

2018-01-01

Amaç: Buaraştırmanın amacı hemşirelerin bireysel ve profesyonel değerleri arasındakikuşaklararası farklılıkları belirlemektir. Gereçve Yöntem: Tanımlayıcı ve karşılaştırmalı tipteki bu çalışma, İzmir’dekibir üniversite hastanesinde çalışan, X kuşağındaki 85(doğum tarihi 1965-1979yılları arasında olanlar) ve Y kuşağındaki 79 (doğum tarihi 1980-1999 yıllarıarasında olanlar) olmak üzere toplam 164 hemşire ile yürütülmüştür. Veriler, araştırmacılar tarafından 30 dakikalık süreiçerisinde yüz yüze ...

Expression of Ku correlates with radiation sensitivities in the head and neck cancer cell lines

International Nuclear Information System (INIS)

Lee, Sang Wook; Yu, Eun Sil; Yi, So Lyoung; Son, Se Hee; Kim, Jong Hoon; Ahn, Seung Do; Shin, Seong Soo; Choi, Eun Kyung

2004-01-01

DNA-dependent protein kinase (DNA-PK) is a serine/threonine kinase consisting of a 470 kDa catalytic subunit (DNA-PKcs) and a heterodimeric regulatory complex, called Ku, which is composed of 70 kDa (Ku 70) and 86 kDa (Ku 80) proteins. The DNA-PK has been shown to play a pivotal role in rejoining DNA double-strand-breaks (dsb) in mammalian cells. The purpose of this study is to examine the relationship between the level of Ku expression and radiation sensitivity. Nine head and neck, cancer cell lines showed various intrinsic radiation sensitivities. Among the nine, AMC-HN-3 cell was the most sensitive for X-ray irradiation and AMC-HN-9 cell was the most resistance. The most sensitive and resistant cell lines were selected and the test sensitivity of radiation and expression of Ku were measured. Radiation sensitivity was obtained by colony forming assay and Ku protein expression using Western blot analysis. Ku80 increased expression by radiation, wheras Ku70 did not. Overexpression of Ku80 protein increased radiation resistance in AMC-HN9 cell line. There was a correlation between Ku80 expression and radiation resistance. Ku80 was shown to play an important role in radiation damage response. Induction of Ku80 expression had an important role in DNA damage repair by radiation. Ku80 expression may be an effective predictive assay of radiosensitivity on head and neck cancer

Ku must load directly onto the chromosome end in order to mediate its telomeric functions.

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Christopher R Lopez

2011-08-01

Full Text Available The Ku heterodimer associates with the Saccharomyces cerevisiae telomere, where it impacts several aspects of telomere structure and function. Although Ku avidly binds DNA ends via a preformed channel, its ability to associate with telomeres via this mechanism could be challenged by factors known to bind directly to the chromosome terminus. This has led to uncertainty as to whether Ku itself binds directly to telomeric ends and whether end association is crucial for Ku's telomeric functions. To address these questions, we constructed DNA end binding-defective Ku heterodimers by altering amino acid residues in Ku70 and Ku80 that were predicted to contact DNA. These mutants continued to associate with their known telomere-related partners, such as Sir4, a factor required for telomeric silencing, and TLC1, the RNA component of telomerase. Despite these interactions, we found that the Ku mutants had markedly reduced association with telomeric chromatin and null-like deficiencies for telomere end protection, length regulation, and silencing functions. In contrast to Ku null strains, the DNA end binding defective Ku mutants resulted in increased, rather than markedly decreased, imprecise end-joining proficiency at an induced double-strand break. This result further supports that it was the specific loss of Ku's telomere end binding that resulted in telomeric defects rather than global loss of Ku's functions. The extensive telomere defects observed in these mutants lead us to propose that Ku is an integral component of the terminal telomeric cap, where it promotes a specific architecture that is central to telomere function and maintenance.

Ku must load directly onto the chromosome end in order to mediate its telomeric functions.

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Lopez, Christopher R; Ribes-Zamora, Albert; Indiviglio, Sandra M; Williams, Christopher L; Haricharan, Svasti; Bertuch, Alison A

2011-08-01

The Ku heterodimer associates with the Saccharomyces cerevisiae telomere, where it impacts several aspects of telomere structure and function. Although Ku avidly binds DNA ends via a preformed channel, its ability to associate with telomeres via this mechanism could be challenged by factors known to bind directly to the chromosome terminus. This has led to uncertainty as to whether Ku itself binds directly to telomeric ends and whether end association is crucial for Ku's telomeric functions. To address these questions, we constructed DNA end binding-defective Ku heterodimers by altering amino acid residues in Ku70 and Ku80 that were predicted to contact DNA. These mutants continued to associate with their known telomere-related partners, such as Sir4, a factor required for telomeric silencing, and TLC1, the RNA component of telomerase. Despite these interactions, we found that the Ku mutants had markedly reduced association with telomeric chromatin and null-like deficiencies for telomere end protection, length regulation, and silencing functions. In contrast to Ku null strains, the DNA end binding defective Ku mutants resulted in increased, rather than markedly decreased, imprecise end-joining proficiency at an induced double-strand break. This result further supports that it was the specific loss of Ku's telomere end binding that resulted in telomeric defects rather than global loss of Ku's functions. The extensive telomere defects observed in these mutants lead us to propose that Ku is an integral component of the terminal telomeric cap, where it promotes a specific architecture that is central to telomere function and maintenance.

Somatic mutation frequency in the stamen hairs of Tradescantia KU 7 and KU 9 clones exposed to low-level gamma rays

International Nuclear Information System (INIS)

Ichikawa, S.; Nagashima, C.; Takahashi, C.S.

1981-01-01

Two triploid clones (KU 7 and KU 9) of Tradescantia heterozygous for flower color were exposed to 1 to 42.3R of gamma rays or the scattering radiation in the gamma field of the Institute of Radiation . Breeding. Occurrence of somatic pink mutations in the stamen hairs was investigated 10 to 16 (or 14) days after irradiation. The mutation frequency was found to increase linearly with increasing gamma-ray exposure in the both clones, and the frequencies of 0.437 and 0.468 pink mutant events per 10 3 hairs per R were determined for KU 7 and KU 9, respectively. When the data collected in the present study were analyzed together with those obtained in earlier experiments in the gamma field, linear relationships of the somatic mutation frequency with gamma-ray (2.1 to 201.6R) and scattering radiation (0.72 to 57.6R) exposures were confirmed. Scattering radiation was found to have a genetical efficiency more than two times higher than that of gamma rays. Variation of spontaneous mutation frequency observed in the present study and in earlier studies was inversely correlated to temperature variation

The Ku80 carboxy terminus stimulates joining and artemis-mediated processing of DNA ends

DEFF Research Database (Denmark)

Weterings, Eric; Verkaik, Nicole S; Keijzers, Guido

2008-01-01

Repair of DNA double-strand breaks (DSBs) is predominantly mediated by nonhomologous end joining (NHEJ) in mammalian cells. NHEJ requires binding of the Ku70-Ku80 heterodimer (Ku70/80) to the DNA ends and subsequent recruitment of the DNA-dependent protein kinase catalytic subunit (DNA-PK(CS)) an......Repair of DNA double-strand breaks (DSBs) is predominantly mediated by nonhomologous end joining (NHEJ) in mammalian cells. NHEJ requires binding of the Ku70-Ku80 heterodimer (Ku70/80) to the DNA ends and subsequent recruitment of the DNA-dependent protein kinase catalytic subunit (DNA......-PK(CS)) and the XRCC4/ligase IV complex. Activation of the DNA-PK(CS) serine/threonine kinase requires an interaction with Ku70/80 and is essential for NHEJ-mediated DSB repair. In contrast to previous models, we found that the carboxy terminus of Ku80 is not absolutely required for the recruitment and activation...... was phosphorylated to normal levels. This resulted in severely reduced levels of Artemis nuclease activity in vivo and in vitro. We therefore conclude that the Ku80 carboxy terminus is important to support DNA-PK(CS) autophosphorylation at specific sites, which facilitates DNA end processing by the Artemis...

Expression of Ku70 predicts results of radiotherapy in prostate cancer

Energy Technology Data Exchange (ETDEWEB)

Hasegawa, Tomokazu; Someya, Masanori; Hori, Masakazu; Nakata, Kensei; Kitagawa, Mio; Tsuchiya, Takaaki; Sakata, Koh-ichi [Sapporo Medical University School of medicine, Department of Radiology, Chuo-ku, Sapporo, Hokkaido (Japan); Matsumoto, Yoshihisa [Research Laboratory for Nuclear Reactors, Tokyo Institute of Technology, Meguro-ku, Tokyo (Japan); Nojima, Masanori [The University of Tokyo, The Institute of Medical Science Hospital, Minatoku, Tokyo (Japan); Masumori, Naoya [Sapporo Medical University School of medicine, Department of Urology, Chuo-ku, Sapporo, Hokkaido (Japan); Hasegawa, Tadashi [Sapporo Medical University School of medicine, Department of Surgical Pathology, Chuo-ku, Sapporo, Hokkaido (Japan)

2017-01-15

Therapeutic strategy for prostate cancer is decided according to T stage, Gleason score, and prostate-specific antigen (PSA) level. These clinical factors are not accurate enough to predict individual risk of local failure of prostate cancer after radiotherapy. Parameters involved with radiosensitivity are required to improve the predictive capability for local relapse. We analyzed 58 patients with localized adenocarcinoma of the prostate between August 2007 and October 2010 treated with 76 Gy of intensity-modulated radiotherapy (IMRT) as a discovery cohort and 42 patients between March 2001 and May 2007 treated with three-dimensional conformal radiotherapy (3D-CRT) as a validation cohort. Immunohistochemical examination for proteins involved in nonhomologous end-joining was performed using biopsy specimens. Ku70 expression was not correlated with various clinical parameters, such as the Gleason score and D'amico risk classification, indicating that Ku70 expression was an independent prognostic factor. The predictive value for PSA relapse was markedly improved after the combination of Gleason score and Ku70 expression, as compared with Gleason score alone. In patients treated with radiotherapy and androgen deprivation therapy (ADT), no relapses were observed in patients with Gleason score ≤7 or low Ku70 expression. In contrast, patients with Gleason score ≥8 and high Ku70 expression had high PSA relapse rates. In the validation cohort, similar results were obtained. Treatment with 76 Gy and ADT can be effective for patients with Gleason score ≤7 or low Ku70 expression, but is not enough for patients with Gleason score ≥8 and high Ku70 expression and, thus, require other treatment approaches. (orig.) [German] Die Behandlung beim Prostatakarzinom ist abhaengig von T-Stadium, Gleason-Score und prostataspezifischem Antigen (PSA). Diese klinischen Faktoren sind jedoch zu ungenau, um das individuelle Lokalrezidivrisiko beim Prostatakarzinom nach

Analysis of a Compact Wideband Slotted Antenna for Ku Band Applications

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M. R. Ahsan

2014-01-01

Full Text Available The design procedure and physical module of a compact wideband patch antenna for Ku band application are presented in this paper. Finite element method based on 3D electromagnetic field solver has been utilized for the designing and analyzing process of proposed microstrip line fed modified E-H shaped electrically small patch antenna. After successful completion of the design process through various simulations, the proposed antenna has been fabricated on printed circuit board (PCB and its characteristics have been studied. The parameters of the proposed antenna prototype have been measured in standard far-field rectangular shape anechoic measurement compartment. It is apparent from the measured antenna parameters that the proposed antenna achieved almost stable variation of radiation pattern over the entire operational band with 1380 MHz of -10 dB return loss bandwidth. The maximum gain of 7.8 dBi and 89.97% average efficiency within the operating band from 17.15 GHz to 18.53 GHz ensure the suitability of the proposed antenna for Ku band applications.

Ku70 is required for late B cell development and immunoglobulin heavy chain class switching.

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Manis, J P; Gu, Y; Lansford, R; Sonoda, E; Ferrini, R; Davidson, L; Rajewsky, K; Alt, F W

1998-06-15

Immunoglobulin (Ig) heavy chain (HC) class switch recombination (CSR) is a late B cell process that involves intrachromosomal DNA rearrangement. Ku70 and Ku80 form a DNA end-binding complex required for DNA double strand break repair and V(D)J recombination. Ku70(-/-) (K70T) mice, like recombination activating gene (RAG)-1- or RAG-2-deficient (R1T or R2T) mice, have impaired B and T cell development at an early progenitor stage, which is thought to result at least in part from defective V(D)J recombination (Gu, Y., K.J. Seidl, G.A. Rathbun, C. Zhu, J.P. Manis, N. van der Stoep, L. Davidson, H.L. Cheng, J.M. Sekiguchi, K. Frank, et al. 1997. Immunity. 7:653-665; Ouyang, H., A. Nussenzweig, A. Kurimasa, V.C. Soares, X. Li, C. Cordon-Cardo, W. Li, N. Cheong, M. Nussenzweig, G. Iliakis, et al. 1997. J. Exp. Med. 186:921-929). Therefore, to examine the potential role of Ku70 in CSR, we generated K70T mice that carry a germline Ig HC locus in which the JH region was replaced with a functionally rearranged VH(D)JH and Ig lambda light chain transgene (referred to as K70T/HL mice). Previously, we have shown that B cells from R1T or R2T mice carrying these rearranged Ig genes (R1T/HL or R2T/HL mice) can undergo CSR to IgG isotypes (Lansford, R., J. Manis, E. Sonoda, K. Rajewsky, and F. Alt. 1998. Int. Immunol. 10:325-332). K70T/HL mice had significant numbers of peripheral surface IgM+ B cells, which generated serum IgM levels similar to those of R2T/HL mice. However, in contrast to R2T/HL mice, K70T/HL mice had no detectable serum IgG isotypes. In vitro culture of K70T/HL B cells with agents that induce CSR in normal or R2T/HL B cells did lead to the induction of germline CH transcripts, indicating that initial signaling pathways for CSR were intact in K70T/HL cells. However, treatment with such agents did not lead to detectable CSR by K70T/HL B cells, and instead, led to cell death within 72 h. We conclude that Ku70 is required for the generation of B cells that have

Mycobacterium tuberculosis Ku can bind to nuclear DNA damage and sensitize mammalian cells to bleomycin sulfate.

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Castore, Reneau; Hughes, Cameron; Debeaux, Austin; Sun, Jingxin; Zeng, Cailing; Wang, Shih-Ya; Tatchell, Kelly; Shi, Runhua; Lee, Kyung-Jong; Chen, David J; Harrison, Lynn

2011-11-01

Radiotherapy and chemotherapy are effective cancer treatments due to their ability to generate DNA damage. The major lethal lesion is the DNA double-strand break (DSB). Human cells predominantly repair DSBs by non-homologous end joining (NHEJ), which requires Ku70, Ku80, DNA-PKcs, DNA ligase IV and accessory proteins. Repair is initiated by the binding of the Ku heterodimer at the ends of the DSB and this recruits DNA-PKcs, which initiates damage signaling and functions in repair. NHEJ also exists in certain types of bacteria that have dormant phases in their life cycle. The Mycobacterium tuberculosis Ku (Mt-Ku) resembles the DNA-binding domain of human Ku but does not have the N- and C-terminal domains of Ku70/80 that have been implicated in binding mammalian NHEJ repair proteins. The aim of this work was to determine whether Mt-Ku could be used as a tool to bind DSBs in mammalian cells and sensitize cells to DNA damage. We generated a fusion protein (KuEnls) of Mt-Ku, EGFP and a nuclear localization signal that is able to perform bacterial NHEJ and hence bind DSBs. Using transient transfection, we demonstrated that KuEnls is able to bind laser damage in the nucleus of Ku80-deficient cells within 10 sec and remains bound for up to 2 h. The Mt-Ku fusion protein was over-expressed in U2OS cells and this increased the sensitivity of the cells to bleomycin sulfate. Hydrogen peroxide and UV radiation do not predominantly produce DSBs and there was little or no change in sensitivity to these agents. Since in vitro studies were unable to detect binding of Mt-Ku to DNA-PKcs or human Ku70/80, this work suggests that KuEnls sensitizes cells by binding DSBs, preventing human NHEJ. This study indicates that blocking or decreasing the binding of human Ku to DSBs could be a method for enhancing existing cancer treatments.

Absence of hemolytic disease of fetus and newborn despite maternal high-titer IgG anti-Ku.

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Kakaiya, R M; Whaley, A; Howard-Menk, C; Rami, J; Papari, M; Campbell-Lee, S; Malecki, Z

2010-01-01

Anti-Ku seen in K(o) (Kell-null) individuals has previously been shown to cause severe hemolytic transfusion reactions. Maternal anti-Ku can cause none or moderate to severe hemolytic disease of the fetus and newborn (HDFN). In two of four previously described HDFN cases, intrauterine transfusions were required because of severe anemia. We report a case in which maternal anti-Ku did not cause HDFN. Standard serologic methods were used for RBC antibody screening and identification, adsorption and elution of RBC antibodies, and antigen typing. A gravida 3, para 3 (G3P3) woman was first evaluated in 2006 and was found to have an IgG RBC antibody that reacted against all panel RBCs in the anti-human globulin phase. A panel of RBCs treated with DTT did not react with the antibody. The antibody failed to react with one example of K(o) RBCs. The patient’s RBCs typed negative for the following Kell blood group antigens: KEL1, KEL2, KEL3, KEL4, KEL6, KEL7, KEL11, KEL13, and KEL18. These results established the presence of anti-Ku in maternal serum. The newborn was group A, D+ and required phototherapy for hyperbilirubinemia, but did not require transfusion. The woman was seen again in January 2010 during the third trimester (G4P3). At this time, anti-Ku titer was 256. She delivered a healthy group O, D+ baby boy at 37 weeks' gestation. Cord RBCs were 4+ for IgG by DAT. An eluate reacted with all RBCs tested, but did not react when tested against a panel of DTT-treated RBCs. K(o) phenotype is rare to begin with, and the maternal anti-Ku formation may require more than one pregnancy. Therefore, cases that can be evaluated for anti-Ku–related HDFN are rare. Our case contributes to serologic and clinical aspects of such rare cases.

Low density lipoprotein receptor gene Ava II polymorphism and serum lipid levels in the Guangxi Bai Ku Yao and Han populations

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Wu Dong-Feng

2011-02-01

Full Text Available Abstract Background Several common genetic polymorphisms in the low density lipoprotein receptor (LDL-R gene have associated with modifications of serum total cholesterol (TC and low density lipoprotein cholesterol (LDL-C levels, but the results are not consistent in different populations. Bai Ku Yao is a special subgroup of the Yao minority in China. The present study was undertaken to detect the association of LDL-R gene Ava Ⅱ polymorphism and serum lipid levels in the Guangxi Bai Ku Yao and Han populations. Methods A total of 1024 subjects of Bai Ku Yao and 792 participants of Han Chinese were randomly selected from our previous stratified randomized cluster samples. Genotyping of the LDL-R gene Ava Ⅱ polymorphism was performed by polymerase chain reaction and restriction fragment length polymorphism combined with gel electrophoresis, and then confirmed by direct sequencing. Results The levels of serum TC, high density lipoprotein cholesterol (HDL-C, LDL-C, apolipoprotein (Apo A1 and the ratio of ApoA1 to ApoB were lower in Bai Ku Yao than in Han (P - and A+ alleles was 65.5% and 34.5% in Bai Ku Yao, and 80.7% and 19.3% in Han (P -A-, A-A+ and A+A+ genotypes was 42.6%, 45.9% and 11.5% in Bai Ku Yao, and 64.9%, 31.6% and 3.5% in Han (P P 3.20 mmol/L subgroups in Bai Ku Yao (P P P P +A+ genotype had higher serum LDL-C, TC, HDL-C or ApoA1 levels than the subjects with A-A+ and A-A- genotypes. Spearman rank correlation analysis revealed that the levels of LDL-C in Bai Ku Yao and HDL-C in Han were correlated with genotypes (P P Conclusions The association of LDL-R gene Ava Ⅱ polymorphism and serum lipid levels is different between the Bai Ku Yao and Han populations. The discrepancy might partly result from different LDL-R gene Ava Ⅱ polymorphism or LDL-R gene-enviromental interactions.

Deletion of individual Ku subunits in mice causes an NHEJ-independent phenotype potentially by altering apurinic/apyrimidinic site repair.

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Yong Jun Choi

Full Text Available Ku70 and Ku80 form a heterodimer called Ku that forms a holoenzyme with DNA dependent-protein kinase catalytic subunit (DNA-PKCS to repair DNA double strand breaks (DSBs through the nonhomologous end joining (NHEJ pathway. As expected mutating these genes in mice caused a similar DSB repair-defective phenotype. However, ku70(-/- cells and ku80(-/- cells also appeared to have a defect in base excision repair (BER. BER corrects base lesions, apurinic/apyrimidinic (AP sites and single stand breaks (SSBs utilizing a variety of proteins including glycosylases, AP endonuclease 1 (APE1 and DNA Polymerase β (Pol β. In addition, deleting Ku70 was not equivalent to deleting Ku80 in cells and mice. Therefore, we hypothesized that free Ku70 (not bound to Ku80 and/or free Ku80 (not bound to Ku70 possessed activity that influenced BER. To further test this hypothesis we performed two general sets of experiments. The first set showed that deleting either Ku70 or Ku80 caused an NHEJ-independent defect. We found ku80(-/- mice had a shorter life span than dna-pkcs(-/- mice demonstrating a phenotype that was greater than deleting the holoenzyme. We also found Ku70-deletion induced a p53 response that reduced the level of small mutations in the brain suggesting defective BER. We further confirmed that Ku80-deletion impaired BER via a mechanism that was not epistatic to Pol β. The second set of experiments showed that free Ku70 and free Ku80 could influence BER. We observed that deletion of either Ku70 or Ku80, but not both, increased sensitivity of cells to CRT0044876 (CRT, an agent that interferes with APE1. In addition, free Ku70 and free Ku80 bound to AP sites and in the case of Ku70 inhibited APE1 activity. These observations support a novel role for free Ku70 and free Ku80 in altering BER.

Predators collected from balsam woolly adelgid and Cooley spruce gall adelgid in western Oregon and Washington, U.S.A., with reference to biological control of hemlock woolly adelgid (Hemiptera: Adelgidae)

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Darrell W. Ross; Glenn R. Kohler; Kimberly F. Wallin

2017-01-01

As part of a comprehensive study to survey predators associated with hemlock woolly adelgid, Adelges tsugae Annand, 1928 in the Pacific Northwest (PNW), U.S.A. (Kohler et al. 2008), predators of balsam woolly adelgid, Adelges piceae (Ratzeburg, 1844) and Cooley spruce gall adelgid, Adelges cooleyi (Gillette...

Preclinical evaluation of (111)In-DTPA-INCA-X anti-Ku70/Ku80 monoclonal antibody in prostate cancer.

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Evans-Axelsson, Susan; Vilhelmsson Timmermand, Oskar; Welinder, Charlotte; Borrebaeck, Carl Ak; Strand, Sven-Erik; Tran, Thuy A; Jansson, Bo; Bjartell, Anders

2014-01-01

The aim of this investigation was to assess the Ku70/Ku80 complex as a potential target for antibody imaging of prostate cancer. We evaluated the in vivo and ex vivo tumor targeting and biodistribution of the (111)In-labeled human internalizing antibody, INCA-X ((111)In-DTPA-INCA-X antibody), in NMRI-nude mice bearing human PC-3, PC-3M-Lu2 or DU145 xenografts. DTPA-conjugated, non-labeled antibody was pre-administered at different time-points followed by a single intravenous injection of (111)In-DTPA-INCA-X. At 48, 72 and 96 h post-injection, tissues were harvested, and the antibody distribution was determined by measuring radioactivity. Preclinical SPECT/CT imaging of mice with and without the predose was performed at 48 hours post-injection of labeled DTPA-INCA-X. Biodistribution of the labeled antibody showed enriched activity in tumor, spleen and liver. Animals pre-administered with DTPA-INCA-X showed increased tumor uptake and blood content of (111)In-DTPA-INCA-X with reduced splenic and liver uptake. The in vitro and in vivo data presented show that the (111)In-labeled INCA-X antibody is internalized into prostate cancer cells and by pre-administering non-labeled DTPA-INCA-X, we were able to significantly reduce the off target binding and increase the (111)In-DTPA-INCA-X mAb uptake in PC-3, PC-3M-Lu2 and DU145 xenografts. The results are encouraging and identifying the Ku70/Ku80 antigen as a target is worth further investigation for functional imaging of prostate cancer.

Preclinical evaluation of 111In-DTPA-INCA-X anti-Ku70/Ku80 monoclonal antibody in prostate cancer

Science.gov (United States)

Evans-Axelsson, Susan; Vilhelmsson Timmermand, Oskar; Welinder, Charlotte; Borrebaeck, Carl AK; Strand, Sven-Erik; Tran, Thuy A; Jansson, Bo; Bjartell, Anders

2014-01-01

The aim of this investigation was to assess the Ku70/Ku80 complex as a potential target for antibody imaging of prostate cancer. We evaluated the in vivo and ex vivo tumor targeting and biodistribution of the 111In-labeled human internalizing antibody, INCA-X (111In-DTPA-INCA-X antibody), in NMRI-nude mice bearing human PC-3, PC-3M-Lu2 or DU145 xenografts. DTPA-conjugated, non-labeled antibody was pre-administered at different time-points followed by a single intravenous injection of 111In-DTPA-INCA-X. At 48, 72 and 96 h post-injection, tissues were harvested, and the antibody distribution was determined by measuring radioactivity. Preclinical SPECT/CT imaging of mice with and without the predose was performed at 48 hours post-injection of labeled DTPA-INCA-X. Biodistribution of the labeled antibody showed enriched activity in tumor, spleen and liver. Animals pre-administered with DTPA-INCA-X showed increased tumor uptake and blood content of 111In-DTPA-INCA-X with reduced splenic and liver uptake. The in vitro and in vivo data presented show that the 111In-labeled INCA-X antibody is internalized into prostate cancer cells and by pre-administering non-labeled DTPA-INCA-X, we were able to significantly reduce the off target binding and increase the 111In-DTPA-INCA-X mAb uptake in PC-3, PC-3M-Lu2 and DU145 xenografts. The results are encouraging and identifying the Ku70/Ku80 antigen as a target is worth further investigation for functional imaging of prostate cancer. PMID:24982817

Pusaudžu - hokeja spēlētāju sasniegumu stratēģijas un apmierinātības izjūta, spēlējot hokeju, saistībā ar vecāku audzināšanas stiliem.

OpenAIRE

Stālmane, Liene

2014-01-01

Maģistra darba mērķis bija izpētīt saistības starp pusaudžu, kuri trenējas hokejā jau no agrīna vecuma, sasniegumu stratēģijām, apmierinātības izjūtu, spēlējot hokeju, un viņu vecāku audzināšanas stilus. Pētījumā tika iekļauti 53 respondenti latviešu tautības zēni, vecumā no 9 – 14 gadiem, kuri trenējas hokejā. Par pētījuma instrumentāriju izmantotas: 1)Vecāku audzināšanas stila aptauja. (Parental Authority Questionnaire (PAQ), Buri, 1991); 2) Sasniegumu stratēģiju aptauja....

Ku recruits XLF to DNA double-strand breaks.

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Yano, Ken-ichi; Morotomi-Yano, Keiko; Wang, Shih-Ya; Uematsu, Naoya; Lee, Kyung-Jong; Asaithamby, Aroumougame; Weterings, Eric; Chen, David J

2008-01-01

XRCC4-like factor (XLF)--also known as Cernunnos--has recently been shown to be involved in non-homologous end-joining (NHEJ), which is the main pathway for the repair of DNA double-strand breaks (DSBs) in mammalian cells. XLF is likely to enhance NHEJ by stimulating XRCC4-ligase IV-mediated joining of DSBs. Here, we report mechanistic details of XLF recruitment to DSBs. Live cell imaging combined with laser micro-irradiation showed that XLF is an early responder to DSBs and that Ku is essential for XLF recruitment to DSBs. Biochemical analysis showed that Ku-XLF interaction occurs on DNA and that Ku stimulates XLF binding to DNA. Unexpectedly, XRCC4 is dispensable for XLF recruitment to DSBs, although photobleaching analysis showed that XRCC4 stabilizes the binding of XLF to DSBs. Our observations showed the direct involvement of XLF in the dynamic assembly of the NHEJ machinery and provide mechanistic insights into DSB recognition.

RECQ HELICASE RECQL4 PARTICIPATES IN NON-HOMOLOGOUS END JOINING AND INTERACTS WITH THE KU COMPLEX

DEFF Research Database (Denmark)

Shamanna, Raghavendra A; Singh, Dharmendra Kumar; Lu, Huiming

2014-01-01

-irradiation and resulted in accumulation of 53BP1 foci after irradiation, indicating defects in the processing of DSB. We find that RECQL4 interacts with the Ku70/Ku80 heterodimer, part of the DNA-dependent protein kinase (DNA-PK) complex, via its N-terminal domain. Further, RECQL4 stimulates higher order DNA binding...... of Ku70/Ku80 to a blunt end DNA substrate. Taken together, these results implicate that RECQL4 participates in the NHEJ pathway of DSB repair via a functional interaction with the Ku70/Ku80 complex. This is the first study to provide both in vitro and in vivo evidence for a role of a RecQ helicase...

Ku-band electromagnetic wave absorbing properties of polysiloxane derived Si-O-C bulk ceramics

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Ding, Donghai; Li, Zipei; Xiao, Guoqing; Yang, Shaoyu

2018-02-01

The bulk Si-O-C ceramics were prepared by polymer derived ceramics (PDCs) route using polysiloxane as precursor and their properties were investigated for electromagnetic wave absorbing in the frequency range of 12.4-18 GHz (Ku-band). It was found that the catalytic pyrolysis can enhance substantially the absorbing properties by in situ formation of turbostratic carbon network, ordered carbon, and multi-wall carbon nanotubes. The matching thickness of sample containing 1.5 wt% FeCl3 (FPSO-1.5) is 2.2 mm, and its reflection loss exceeds -10 dB in the whole Ku-band with an absorption peak of -35.48 dB at 14.16 GHz. For sample containing 1.5 wt% FeCl3, its absorption peak increases to -15.78 dB, but its matching thickness decreases significantly to 2.2 mm. The polymer derived Si-O-C ceramics could be used as excellent electromagnetic functional devices working in harsh environments.

Construction of cell model of silenced Ku80 and the radiobiology change of HeLa cell

International Nuclear Information System (INIS)

Zhuang Liang; Yu Shiying; Huang Xiaoyuan; Xiong Huihua; Xiong Hua; Li Xiaolan; Leng Yan

2007-01-01

Objective: To construct the cell model of Ku80 with expression inhibited by siRNA and to explore the role of Ku80 in radiobiology. Methods: Ku80-siRNA expression plasmids were constructed and HeLa cells were transfected with these plasmids by lipofectamine. Western blotting was used to measure the expression of Ku80. After irradiation with 6 MV X ray, cells were collected and analyzed by flow cytometry for apoptosis and cell cycle at 24, 48 and 72 h; The radiobiology parameters of four cell lines were acquired by clone formation array. Results: Three stable transfected cell clones were obtained, and the inhibition rates of Ku80 protein expression of two positive clones were 89.3% and 96.4%; The apoptosis rates of HeLa cells Ku80 inhibited were higher than control cells at 48 and 72 after X ray irradiation (P 0.05). HeLa cells of silenced Ku80 had lower SF 2 and D 0 than control cells, and their SER (sensitization enhancement ratio) based on D 10 were 1.315 and 1.365, respectively. Conclusions: The HeLa cell models with Ku80 expression suppressed were successfully established; the inhibition of Ku80 by siRNA could enhance the radiosensitivity of HeLa cells. (authors)

The Ku80 carboxy terminus stimulates joining and artemis-mediated processing of DNA ends.

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Weterings, Eric; Verkaik, Nicole S; Keijzers, Guido; Florea, Bogdan I; Wang, Shih-Ya; Ortega, Laura G; Uematsu, Naoya; Chen, David J; van Gent, Dik C

2009-03-01

Repair of DNA double-strand breaks (DSBs) is predominantly mediated by nonhomologous end joining (NHEJ) in mammalian cells. NHEJ requires binding of the Ku70-Ku80 heterodimer (Ku70/80) to the DNA ends and subsequent recruitment of the DNA-dependent protein kinase catalytic subunit (DNA-PK(CS)) and the XRCC4/ligase IV complex. Activation of the DNA-PK(CS) serine/threonine kinase requires an interaction with Ku70/80 and is essential for NHEJ-mediated DSB repair. In contrast to previous models, we found that the carboxy terminus of Ku80 is not absolutely required for the recruitment and activation of DNA-PK(CS) at DSBs, although cells that harbored a carboxy-terminal deletion in the Ku80 gene were sensitive to ionizing radiation and showed reduced end-joining capacity. More detailed analysis of this repair defect showed that DNA-PK(CS) autophosphorylation at Thr2647 was diminished, while Ser2056 was phosphorylated to normal levels. This resulted in severely reduced levels of Artemis nuclease activity in vivo and in vitro. We therefore conclude that the Ku80 carboxy terminus is important to support DNA-PK(CS) autophosphorylation at specific sites, which facilitates DNA end processing by the Artemis endonuclease and the subsequent joining reaction.

The Ku80 Carboxy Terminus Stimulates Joining and Artemis-Mediated Processing of DNA Ends▿

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Weterings, Eric; Verkaik, Nicole S.; Keijzers, Guido; Florea, Bogdan I.; Wang, Shih-Ya; Ortega, Laura G.; Uematsu, Naoya; Chen, David J.; van Gent, Dik C.

2009-01-01

Repair of DNA double-strand breaks (DSBs) is predominantly mediated by nonhomologous end joining (NHEJ) in mammalian cells. NHEJ requires binding of the Ku70-Ku80 heterodimer (Ku70/80) to the DNA ends and subsequent recruitment of the DNA-dependent protein kinase catalytic subunit (DNA-PKCS) and the XRCC4/ligase IV complex. Activation of the DNA-PKCS serine/threonine kinase requires an interaction with Ku70/80 and is essential for NHEJ-mediated DSB repair. In contrast to previous models, we found that the carboxy terminus of Ku80 is not absolutely required for the recruitment and activation of DNA-PKCS at DSBs, although cells that harbored a carboxy-terminal deletion in the Ku80 gene were sensitive to ionizing radiation and showed reduced end-joining capacity. More detailed analysis of this repair defect showed that DNA-PKCS autophosphorylation at Thr2647 was diminished, while Ser2056 was phosphorylated to normal levels. This resulted in severely reduced levels of Artemis nuclease activity in vivo and in vitro. We therefore conclude that the Ku80 carboxy terminus is important to support DNA-PKCS autophosphorylation at specific sites, which facilitates DNA end processing by the Artemis endonuclease and the subsequent joining reaction. PMID:19103741

The Ku Heterodimer and the Metabolism of Single-Ended DNA Double-Strand Breaks

Directory of Open Access Journals (Sweden)

Alessia Balestrini

2013-06-01

Full Text Available Single-ended double-strand breaks (DSBs are a common form of spontaneous DNA break, generated when the replisome encounters a discontinuity in the DNA template. Given their prevalence, understanding the mechanisms governing the fate(s of single-ended DSBs is important. We describe the influence of the Ku heterodimer and Mre11 nuclease activity on processing of single-ended DSBs. Separation-of-function alleles of yku70 were derived that phenocopy Ku deficiency with respect to single-ended DSBs but remain proficient for NHEJ. The Ku mutants fail to regulate Exo1 activity, and bypass the requirement for Mre11 nuclease activity in the repair of camptothecin-induced single-ended DSBs. Ku mutants exhibited reduced affinity for DNA ends, manifest as both reduced end engagement and enhanced probability of diffusing inward on linear DNA. This study reveals an interplay between Ku and Mre11 in the metabolism of single-ended DSBs that is distinct from repair pathway choice at double-ended DSBs.

Ku proteins function as corepressors to regulate farnesoid X receptor-mediated gene expression

International Nuclear Information System (INIS)

Ohno, Masae; Kunimoto, Masaaki; Nishizuka, Makoto; Osada, Shigehiro; Imagawa, Masayoshi

2009-01-01

The farnesoid X receptor (FXR; NR1H4) is a member of the nuclear receptor superfamily and regulates the expression of genes involved in enterohepatic circulation and the metabolism of bile acids. Based on functional analyses, nuclear receptors are divided into regions A-F. To explore the cofactors interacting with FXR, we performed a pull-down assay using GST-fused to the N-terminal A/B region and the C region, which are required for the ligand-independent transactivation and DNA-binding, respectively, of FXR, and nuclear extracts from HeLa cells. We identified DNA-dependent protein kinase catalytic subunit (DNA-PKcs), Ku80, and Ku70 as FXR associated factors. These proteins are known to have an important role in DNA repair, recombination, and transcription. DNA-PKcs mainly interacted with the A/B region of FXR, whereas the Ku proteins interacted with the C region and with the D region (hinge region). Chromatin immunoprecipitation assays revealed that the Ku proteins associated with FXR on the bile salt export pump (BSEP) promoter. Furthermore, we demonstrated that ectopic expression of the Ku proteins decreased the promoter activity and expression of BSEP gene mediated by FXR. These results suggest that the Ku proteins function as corepressors for FXR.

The Ku heterodimer and the metabolism of single-ended DNA double-strand breaks.

Science.gov (United States)

Balestrini, Alessia; Ristic, Dejan; Dionne, Isabelle; Liu, Xiao Z; Wyman, Claire; Wellinger, Raymund J; Petrini, John H J

2013-06-27

Single-ended double-strand breaks (DSBs) are a common form of spontaneous DNA break, generated when the replisome encounters a discontinuity in the DNA template. Given their prevalence, understanding the mechanisms governing the fate(s) of single-ended DSBs is important. We describe the influence of the Ku heterodimer and Mre11 nuclease activity on processing of single-ended DSBs. Separation-of-function alleles of yku70 were derived that phenocopy Ku deficiency with respect to single-ended DSBs but remain proficient for NHEJ. The Ku mutants fail to regulate Exo1 activity, and bypass the requirement for Mre11 nuclease activity in the repair of camptothecin-induced single-ended DSBs. Ku mutants exhibited reduced affinity for DNA ends, manifest as both reduced end engagement and enhanced probability of diffusing inward on linear DNA. This study reveals an interplay between Ku and Mre11 in the metabolism of single-ended DSBs that is distinct from repair pathway choice at double-ended DSBs. Copyright © 2013 The Authors. Published by Elsevier Inc. All rights reserved.

DNA-PK/Ku complex binds to latency-associated nuclear antigen and negatively regulates Kaposi's sarcoma-associated herpesvirus latent replication

International Nuclear Information System (INIS)

Cha, Seho; Lim, Chunghun; Lee, Jae Young; Song, Yoon-Jae; Park, Junsoo; Choe, Joonho; Seo, Taegun

2010-01-01

During latent infection, latency-associated nuclear antigen (LANA) of Kaposi's sarcoma-associated herpesvirus (KSHV) plays important roles in episomal persistence and replication. Several host factors are associated with KSHV latent replication. Here, we show that the catalytic subunit of DNA protein kinase (DNA-PKcs), Ku70, and Ku86 bind the N-terminal region of LANA. LANA was phosphorylated by DNA-PK and overexpression of Ku70, but not Ku86, impaired transient replication. The efficiency of transient replication was significantly increased in the HCT116 (Ku86 +/-) cell line, compared to the HCT116 (Ku86 +/+) cell line, suggesting that the DNA-PK/Ku complex negatively regulates KSHV latent replication.

Vecāku audzināšanas stilu saistība ar pašcieņu pusaudžu vecumā

OpenAIRE

Miķelsone-Ježaka, Dace

2008-01-01

Darba mērķis ir izpētīt pašcieņas saistību ar mātes un tēvu audzināšanas stilu bērnībā. Pētījumā piedalījās 105 pusaudži no dažādām skolām vecumā no 16 līdz 18 gadiem, kas dzīvo pilnās ģimenēs. Tika izmantotas 2 aptaujas: 1. Vecāku autoritātes novērtējuma aptauja (The Parental Authority Questionnaire, Buri, 1991; Griškina, 2002). 2. Rozenberga pašcieņas aptauja (The Rosenberg Self – esteem Scale, Rosenberg, 1965).

Synthesis of 6-[18F] and 4-[18F]fluoro-L-m-tyrosines via regioselective radiofluorodestannylation

International Nuclear Information System (INIS)

Namavari, Mohammad; Satyamurthy, N.; Phelps, M.E.; Barrio, J.R.; California Univ., Los Angeles, CA

1993-01-01

The regioselective radiofluorodestannylation of 6-trimethylstannyl-L-m-tyrosine derivative with [ 18 F]F 2 and [ 18 F]acetyl hypofluorite afforded, after acid hydrolysis, 6-[ 18 F]fluoro-L-m-tyrosine in radiochemical yields of 23 and 17%, respectively. Similarly, 4-[ 18 F]fluoro-L-m-tyrosine was synthesized in 11% radiochemical yield from the corresponding 4-trimethylstannyl-L-m-tyrosine derivative using [ 18 F]F 2 . The structural analyses of precursors, intermediates, and the final products (after 18 F decay), were carried out by 1 H, 13 C, 19 F, 119 Sn-NMR and high resolution mass spectroscopy. (author)

Degree of conversion and microhardness of TPO-containing resin-based composites cured by polywave and monowave LED units.

Science.gov (United States)

Santini, Ario; Miletic, Vesna; Swift, Michael D; Bradley, Mark

2012-07-01

To determine the degree of conversion (DC) and Knoop microhardness (KHN) of resin-based composites (RBCs) containing trimethylbenzoyl-diphenylphosphine oxide (TPO) cured by polywave or monowave LED light-curing units (LCUs). Three groups (each n = 5) of Tetric EvoCeram (Ivoclar Vivadent), Vit-l-escence (Ultradent) and Herculite XRV Ultra (Kerr) were prepared in Teflon moulds (5mm in diameter and 2mm thick) and cured with polywave Bluephase(®) G2 (Ivoclar Vivadent), polywave Valo (Ultradent) or monowave Bluephase(®) (Ivoclar Vivadent; control) resulting in 9 groups. DC and KHN were determined using micro-Raman spectroscopy and Knoop microhardness, respectively. High-performance liquid chromatography and nuclear magnetic resonance spectroscopy were used to confirm the presence or absence of TPO in the three uncured materials. Data were statistically analysed using two-way and one-way ANOVA and DC and KHN were correlated using Pearson's correlation (α = 0.05). TPO was confirmed in Tetric EvoCeram and Vit-l-escence but not in Herculite XRV Ultra. All three LCUs produced comparable KHN for Tetric EvoCeram and Herculite XRV Ultra (p > 0.05). Both polywave LCUs resulted in significantly higher KHN for Vit-l-escence and higher DC in Tetric EvoCeram and Vit-l-escence than the monowave Bluephase(®) (p Conversely, Bluephase(®) showed higher DC than the two polywave LCUs in Herculite XRV Ultra (p conversion and KHN in the two TPO-containing RBCs, but not in Herculite XRV Ultra. DC and KHN were linearly correlated in all three RBCs. Vit-l-escence showed the highest DC and KHN of the three materials tested. The use of polywave LEDs significantly improves both the DC and KHN of materials which contain TPO. This should be taken into account when curing bleached shades of RBCs even if the manufacturers do not indicate the presence of TPO in their materials. Copyright © 2012 Elsevier Ltd. All rights reserved.

Airborn Ku-band polarimetric radar remote sensing of terrestrial snow cover

Science.gov (United States)

Simon H. Yueh; Steve J. Dinardo; Ahmed Akgiray; Richard West; Donald W. Cline; Kelly Elder

2009-01-01

Characteristics of the Ku-band polarimetric scatterometer (POLSCAT) data acquired from five sets of aircraft flights in the winter months of 2006-2008 for the second Cold Land Processes Experiment (CLPX-II) in Colorado are described in this paper. The data showed the response of the Ku-band radar echoes to snowpack changes for various types of background vegetation in...

Drosophila UTX coordinates with p53 to regulate ku80 expression in response to DNA damage.

Directory of Open Access Journals (Sweden)

Chengwan Zhang

Full Text Available UTX is known as a general factor that activates gene transcription during development. Here, we demonstrate an additional essential role of UTX in the DNA damage response, in which it upregulates the expression of ku80 in Drosophila, both in cultured cells and in third instar larvae. We further showed that UTX mediates the expression of ku80 by the demethylation of H3K27me3 at the ku80 promoter upon exposure to ionizing radiation (IR in a p53-dependent manner. UTX interacts physically with p53, and both UTX and p53 are recruited to the ku80 promoter following IR exposure in an interdependent manner. In contrast, the loss of utx has little impact on the expression of ku70, mre11, hid and reaper, suggesting the specific regulation of ku80 expression by UTX. Thus, our findings further elucidate the molecular function of UTX.

C-terminal low-complexity sequence repeats of Mycobacterium smegmatis Ku modulate DNA binding.

Science.gov (United States)

Kushwaha, Ambuj K; Grove, Anne

2013-01-24

Ku protein is an integral component of the NHEJ (non-homologous end-joining) pathway of DSB (double-strand break) repair. Both eukaryotic and prokaryotic Ku homologues have been characterized and shown to bind DNA ends. A unique feature of Mycobacterium smegmatis Ku is its basic C-terminal tail that contains several lysine-rich low-complexity PAKKA repeats that are absent from homologues encoded by obligate parasitic mycobacteria. Such PAKKA repeats are also characteristic of mycobacterial Hlp (histone-like protein) for which they have been shown to confer the ability to appose DNA ends. Unexpectedly, removal of the lysine-rich extension enhances DNA-binding affinity, but an interaction between DNA and the PAKKA repeats is indicated by the observation that only full-length Ku forms multiple complexes with a short stem-loop-containing DNA previously designed to accommodate only one Ku dimer. The C-terminal extension promotes DNA end-joining by T4 DNA ligase, suggesting that the PAKKA repeats also contribute to efficient end-joining. We suggest that low-complexity lysine-rich sequences have evolved repeatedly to modulate the function of unrelated DNA-binding proteins.

Shuttle orbiter Ku-band radar/communications system design evaluation. Deliverable test equipment evaluation

Science.gov (United States)

Maronde, R. G.

1980-07-01

The Ku-band test equipment, known as the Deliverable System Test equipment (DSTE), is reviewed and evaluated. The DSTE is semiautomated and computer programs were generated for 14 communication mode tests and 17 radar mode tests. The 31 test modules provide a good cross section of tests with which to exercise the Ku-band system; however, it is very limited when being used to verify Ku-band system performance. More detailed test descriptions are needed, and a major area of concern is the DSTE sell-off procedure which is inadequate.

Improving DNA double-strand repair inhibitor KU55933 therapeutic index in cancer radiotherapy using nanoparticle drug delivery

Science.gov (United States)

Tian, Xi; Lara, Haydee; Wagner, Kyle T.; Saripalli, Srinivas; Hyder, Syed Nabeel; Foote, Michael; Sethi, Manish; Wang, Edina; Caster, Joseph M.; Zhang, Longzhen; Wang, Andrew Z.

2015-11-01

Radiotherapy is a key component of cancer treatment. Because of its importance, there has been high interest in developing agents and strategies to further improve the therapeutic index of radiotherapy. DNA double-strand repair inhibitors (DSBRIs) are among the most promising agents to improve radiotherapy. However, their clinical translation has been limited by their potential toxicity to normal tissue. Recent advances in nanomedicine offer an opportunity to overcome this limitation. In this study, we aim to demonstrate the proof of principle by developing and evaluating nanoparticle (NP) formulations of KU55933, a DSBRI. We engineered a NP formulation of KU55933 using nanoprecipitation method with different lipid polymer nanoparticle formulation. NP KU55933 using PLGA formulation has the best loading efficacy as well as prolonged drug release profile. We demonstrated that NP KU55933 is a potent radiosensitizer in vitro using clonogenic assay and is more effective as a radiosensitizer than free KU55933 in vivo using mouse xenograft models of non-small cell lung cancer (NSCLC). Western blots and immunofluorescence showed NP KU55933 exhibited more prolonged inhibition of DNA repair pathway. In addition, NP KU55933 leads to lower skin toxicity than KU55933. Our study supports further investigations using NP to deliver DSBRIs to improve cancer radiotherapy treatment.

Development of intense terahertz coherent synchrotron radiation at KU-FEL

Energy Technology Data Exchange (ETDEWEB)

Sei, Norihiro, E-mail: sei.n@aist.go.jp [Research Institute for Measurement and Analytical Instrumentation, National Institute of Advanced Industrial Science and Technology, 1-1-1 Umezono, Umezono, Tsukuba, Ibaraki 305-8568 (Japan); Zen, Heishun; Ohgaki, Hideaki [Institute for Advanced Energy, Kyoto University, Gokasho, Uji, Kyoto 611-0011 (Japan)

2016-10-01

We produced intense coherent synchrotron radiation (CSR) in the terahertz (THz) region using an S-band linac at the Kyoto University Free Electron Laser (KU-FEL), which is a mid-infrared free-electron laser facility. The CSR beam was emitted from short-pulse electron bunches compressed by a 180° arc, and was transferred to air at a large solid angle of 0.10 rad. The measured CSR energy was 55 μJ per 7 μs macropulse, and KU-FEL was one of the most powerful CSR sources in normal conducting linear accelerator facilities. The CSR spectra were measured using an uncooled pyroelectric detector and a Michelson-type interferometer designed specifically for the KU-FEL electron beam, and had a maximum at a frequency of 0.11 THz. We found that adjusting the energy slit enhanced the CSR energy and shortened the electron beam bunch length in the CSR spectra measurements. Our results demonstrated that the efficient use of the energy slit can help improve the characteristics of CSR. - Highlights: • We have developed intense coherent synchrotron radiation (CSR) at KU-FEL. • The elevation angle of the CSR was correctly measured by a new technique. • The CSR power extracted to the air was 55 μJ per 7 μs macropulse. • It was demonstrated that an energy slit was effective to improve the CSR properties.

Development of intense terahertz coherent synchrotron radiation at KU-FEL

International Nuclear Information System (INIS)

Sei, Norihiro; Zen, Heishun; Ohgaki, Hideaki

2016-01-01

We produced intense coherent synchrotron radiation (CSR) in the terahertz (THz) region using an S-band linac at the Kyoto University Free Electron Laser (KU-FEL), which is a mid-infrared free-electron laser facility. The CSR beam was emitted from short-pulse electron bunches compressed by a 180° arc, and was transferred to air at a large solid angle of 0.10 rad. The measured CSR energy was 55 μJ per 7 μs macropulse, and KU-FEL was one of the most powerful CSR sources in normal conducting linear accelerator facilities. The CSR spectra were measured using an uncooled pyroelectric detector and a Michelson-type interferometer designed specifically for the KU-FEL electron beam, and had a maximum at a frequency of 0.11 THz. We found that adjusting the energy slit enhanced the CSR energy and shortened the electron beam bunch length in the CSR spectra measurements. Our results demonstrated that the efficient use of the energy slit can help improve the characteristics of CSR. - Highlights: • We have developed intense coherent synchrotron radiation (CSR) at KU-FEL. • The elevation angle of the CSR was correctly measured by a new technique. • The CSR power extracted to the air was 55 μJ per 7 μs macropulse. • It was demonstrated that an energy slit was effective to improve the CSR properties.

Double strand break rejoining by the Ku-dependent mechanism of non-homologous end-joining

International Nuclear Information System (INIS)

Jeggo, P.; Singleton, B.; Beamish, H.; Priestley, A.

1999-01-01

The DNA-dependent protein kinase functions in the repair of DNA double strand breaks (DSBs) and in V(D)J recombination. To gain insight into the function of DNA-PK in this process we have carried out a mutation analysis of Ku80 and DNA-PKcs. Mutations at multiple sites within the N-terminal two thirds of Ku80 result in loss of Ku70/80 interaction, loss of DNA end-binding activity and inability to complement Ku80 defective cell fines. In contrast, mutations in the carboxy terminal region of the protein do not impair DNA end-binding activity but decrease the ability of Ku to activate DNA-PK. To gain insight into important functional domains within DNA-PKcs, we have analysed defective mutants, including the mouse scid cell line, and the rodent mutants, ire-20 and V-3. Mutational changes in the carboxy terminal region have been identified in all cases. Our results strongly suggest that the C-terminus of DNA-PKcs is required for kinase activity. (author)

Vecāku un bērnu mantiskās attiecības

OpenAIRE

Krauja, Uldis

2009-01-01

Bakalaura darba "Vecāku un bērna mantiskās attiecības" mērķis ir izpētīt vecāku un bērna mantisko attiecību regulējumu Latvijas Republikas normatīvajos tiesību aktos, atklājot tajos iespējamās problēmas un nepilnības. Bakalaura darba pirmajā daļā apskatīts vecāku un bērna mantisko attiecību jēdziens un izpratne, pievērsta uzmanība uz vecāku un bērna mantisko attiecību pirmsākumiem caur vēstures prizmu, lai apzinātos ģimenes tiesību nozīmīgumu cilvēces attīstībā un tagadējā dzīvē. Bakalaura da...

Synthetic lethality between murine DNA repair factors XLF and DNA-PKcs is rescued by inactivation of Ku70

DEFF Research Database (Denmark)

Xing, Mengtan; Bjørås, Magnar; Daniel, Jeremy A

2017-01-01

DNA double-strand breaks (DSBs) are recognized and repaired by the Classical Non-Homologous End-Joining (C-NHEJ) and Homologous Recombination pathways. C-NHEJ includes the core Ku70 and Ku80 (or Ku86) heterodimer that binds DSBs and thus promotes recruitment of accessory downstream NHEJ factors XLF......, PAXX, DNA-PKcs, Artemis and other core subunits, XRCC4 and DNA Ligase 4 (Lig4). In the absence of core C-NHEJ factors, DNA repair can be performed by Alternative End-Joining, which likely depends on DNA Ligase 1 and DNA Ligase 3. Genetic inactivation of C-NHEJ factors, such as Ku70, Ku80, XLF, PAXX...... with severe apoptosis in the central nervous system. Here, we demonstrate that inactivation of the Ku70 gene rescues the synthetic lethality between XLF and DNA-PKcs, resulting in triple knockout mice that are indistinguishable from Ku70-deficient littermates by size or levels of genomic instability. Moreover...

Downregulated Ku70 and ATM associated to poor prognosis in colorectal cancer among Chinese patients

Directory of Open Access Journals (Sweden)

Lu YF

2014-10-01

Full Text Available Yuanfang Lu,1,2 Jingyan Gao,1,3 Yuanming Lu,1 1Department of Toxicology, School of Public Health, Guilin Medical University, Guangxi, People's Republic of China; 2Department of Clinical Research Center, Affiliated 2nd Hospital of Nanjing Medical University, Nanjing, People's Republic of China; 3Department of Human Anatomy and Histo-Embryology, Shanghai Medical College, Fudan University, Shanghai, People's Republic of China Background: Double-strand DNA breaks (DSBs are a key factor in carcinogenesis. The necessary repair of DSBs is pivotal in maintaining normal cell division. To address the relationship between altered expression of DSB repair of proteins Ku70 and ataxia-telangiectasia mutated (ATM in colorectal cancer (CRC, we examined the expression levels and patterns of Ku70 and ATM in CRC samples. Methods: Expression and coexpression of Ku70 and ATM were investigated by using real-time quantitative polymerase chain reaction assays and confirmed further with fluorescent immunohistochemistry in CRC and pericancerous samples from 112 Chinese patients. Results: Downexpression patterns for both Ku70 and ATM were found in the CRC samples and were significantly associated with advanced tumor node metastasis stage and decreased 5-year overall survival rate. Conclusion: Downregulated Ku70 and ATM were associated with poor disease-free survival. Loss of Ku70 and ATM expression might act as a biomarker to predict poor prognosis in patients with CRC. Keywords: DNA double-strand breaks, ataxia-telangiectasia mutated, Ku70, colorectal cancer

Ku-mediated coupling of DNA cleavage and repair during programmed genome rearrangements in the ciliate Paramecium tetraurelia.

Directory of Open Access Journals (Sweden)

Antoine Marmignon

2014-08-01

Full Text Available During somatic differentiation, physiological DNA double-strand breaks (DSB can drive programmed genome rearrangements (PGR, during which DSB repair pathways are mobilized to safeguard genome integrity. Because of their unique nuclear dimorphism, ciliates are powerful unicellular eukaryotic models to study the mechanisms involved in PGR. At each sexual cycle, the germline nucleus is transmitted to the progeny, but the somatic nucleus, essential for gene expression, is destroyed and a new somatic nucleus differentiates from a copy of the germline nucleus. In Paramecium tetraurelia, the development of the somatic nucleus involves massive PGR, including the precise elimination of at least 45,000 germline sequences (Internal Eliminated Sequences, IES. IES excision proceeds through a cut-and-close mechanism: a domesticated transposase, PiggyMac, is essential for DNA cleavage, and DSB repair at excision sites involves the Ligase IV, a specific component of the non-homologous end-joining (NHEJ pathway. At the genome-wide level, a huge number of programmed DSBs must be repaired during this process to allow the assembly of functional somatic chromosomes. To understand how DNA cleavage and DSB repair are coordinated during PGR, we have focused on Ku, the earliest actor of NHEJ-mediated repair. Two Ku70 and three Ku80 paralogs are encoded in the genome of P. tetraurelia: Ku70a and Ku80c are produced during sexual processes and localize specifically in the developing new somatic nucleus. Using RNA interference, we show that the development-specific Ku70/Ku80c heterodimer is essential for the recovery of a functional somatic nucleus. Strikingly, at the molecular level, PiggyMac-dependent DNA cleavage is abolished at IES boundaries in cells depleted for Ku80c, resulting in IES retention in the somatic genome. PiggyMac and Ku70a/Ku80c co-purify as a complex when overproduced in a heterologous system. We conclude that Ku has been integrated in the Paramecium

Volba idolů ve školním věku (Pop-Pantheon)

OpenAIRE

Ryba, Zdeněk

2016-01-01

Title: Idolization In The School Age (Pop-Pantheon) Author: Zdeněk Ryba Department: Department of Psychology Supervizor: doc. PhDr. Miloš Kučera, CSc. The main theme of this thesis is basic-school-age children choice of idols. The work is a part of Miloš Kučera research at Faculty of Education UK and it follows up the Mikšíček (1999) and Kravcová (2008) conclusions in their diploma thesis and short Kučera's contribution. The goal of this thesis is to make a database of idols and to create mod...

Uloga kućnih ljubimaca u socioemocionalnom  razvoju djece školskog uzrasta

OpenAIRE

Smojver-Ažić, Sanja; Topalović, Zorica

2010-01-01

Rezultati istraživanja potvrđuju kako je odrastanje uz kućnoga ljubimca povezano sa socioemocionalnim razvojem djece. Cilj ovoga istraživanja bio je ispitati odnos u kojemu stoje privrženost majci, privrženost kućnomu ljubimcu i empatija, socijalna kompetencija i usamljenost. U istraživanju je sudjelovalo 480 učenika četvrtoga, šestoga i osmoga razreda osnovnih škola u Istri (226 djevojčica i 254 dječaka) te njihovi roditelji. U ispitanom uzorku 63 % djece ima jednoga ili više kućnih ljubi...

The Ku70/80 ring in Non-Homologous End-Joining

DEFF Research Database (Denmark)

Kragelund, Birthe Brandt; Weterings, Eric; Hartmann-Petersen, Rasmus

2016-01-01

/80 heterodimer is a key-player in the NHEJ pathway and binds to DNA termini with high affinity, where it helps to protect DNA ends from degradation and to recruit other NHEJ factors required for repair. The mechanism of Ku70/80 detachment from the DNA helix after completion of DNA repair is incompletely......Non-homologous end-joining (NHEJ) is an essential DNA double strand break repair pathway during all cell cycle stages. Deficiency in NHEJ factors can lead to accumulation of unrepaired DNA breaks or faulty DNA repair, which may ultimately result in cell death, senescence or carcinogenesis. The Ku70...... understood. Some data suggest that certain DNA repair factors are ubiquitylated and targeted for proteasomal degradation after repair. Recent studies suggest that Ku80 is conjugated to lysine48-linked ubiquitin chains by the Skp1-Cullin-F-box (SCF) complex and/or the RING finger protein 8 (RNF8) ubiquitin-protein...

Xrcc1-dependent and Ku-dependent DNA double-strand break repair kinetics in Arabidopsis plants.

Science.gov (United States)

Charbonnel, Cyril; Gallego, Maria E; White, Charles I

2010-10-01

Double-strand breakage (DSB) of DNA involves loss of information on the two strands of the DNA fibre and thus cannot be repaired by simple copying of the complementary strand which is possible with single-strand DNA damage. Homologous recombination (HR) can precisely repair DSB using another copy of the genome as template and non-homologous recombination (NHR) permits repair of DSB with little or no dependence on DNA sequence homology. In addition to the well-characterised Ku-dependent non-homologous end-joining (NHEJ) pathway, much recent attention has been focused on Ku-independent NHR. The complex interrelationships and regulation of NHR pathways remain poorly understood, even more so in the case of plants, and we present here an analysis of Ku-dependent and Ku-independent repair of DSB in Arabidopsis thaliana. We have characterised an Arabidopsis xrcc1 mutant and developed quantitative analysis of the kinetics of appearance and loss of γ-H2AX foci as a tool to measure DSB repair in dividing root tip cells of γ-irradiated plants in vivo. This approach has permitted determination of DSB repair kinetics in planta following a short pulse of γ-irradiation, establishing the existence of a Ku-independent, Xrcc1-dependent DSB repair pathway. Furthermore, our data show a role for Ku80 during the first minutes post-irradiation and that Xrcc1 also plays such a role, but only in the absence of Ku. The importance of Xrcc1 is, however, clearly visible at later times in the presence of Ku, showing that alternative end-joining plays an important role in DSB repair even in the presence of active NHEJ. © 2010 The Authors. Journal compilation © 2010 Blackwell Publishing Ltd.

A novel small molecule inhibitor of the DNA repair protein Ku70/80.

Science.gov (United States)

Weterings, Eric; Gallegos, Alfred C; Dominick, Lauren N; Cooke, Laurence S; Bartels, Trace N; Vagner, Josef; Matsunaga, Terry O; Mahadevan, Daruka

2016-07-01

Non-Homologous End-Joining (NHEJ) is the predominant pathway for the repair of DNA double strand breaks (DSBs) in human cells. The NHEJ pathway is frequently upregulated in several solid cancers as a compensatory mechanism for a separate DSB repair defect or for innate genomic instability, making this pathway a powerful target for synthetic lethality approaches. In addition, NHEJ reduces the efficacy of cancer treatment modalities which rely on the introduction of DSBs, like radiation therapy or genotoxic chemotherapy. Consequently, inhibition of the NHEJ pathway can modulate a radiation- or chemo-refractory disease presentation. The Ku70/80 heterodimer protein plays a pivotal role in the NHEJ process. It possesses a ring-shaped structure with high affinity for DSBs and serves as the first responder and central scaffold around which the rest of the repair complex is assembled. Because of this central position, the Ku70/80 dimer is a logical target for the disruption of the entire NHEJ pathway. Surprisingly, specific inhibitors of the Ku70/80 heterodimer are currently not available. We here describe an in silico, pocket-based drug discovery methodology utilizing the crystal structure of the Ku70/80 heterodimer. We identified a novel putative small molecule binding pocket and selected several potential inhibitors by computational screening. Subsequent biological screening resulted in the first identification of a compound with confirmed Ku-inhibitory activity in the low micro-molar range, capable of disrupting the binding of Ku70/80 to DNA substrates and impairing Ku-dependent activation of another NHEJ factor, the DNA-PKCS kinase. Importantly, this compound synergistically sensitized human cell lines to radiation treatment, indicating a clear potential to diminish DSB repair. The chemical scaffold we here describe can be utilized as a lead-generating platform for the design and development of a novel class of anti-cancer agents. Copyright © 2016 Elsevier B.V. All

Molecular characterization of resistant chronic lymphocytic leukemia (CLL): function of a new phosphorylated form of Ku70

International Nuclear Information System (INIS)

Saad, Lina

2013-01-01

We have identified a new form of phospho-S27-S33-Ku70 constitutively over expressed in a subset of chronic lymphocytic leukemia (CLL) B cells resistant to apoptosis induced by DNA double strand breaks (DSB). Ku70 is one of the essential proteins involved in the maintenance of genomic stability through its role in DNA double strand break repair (non-homologous end-joining, NHEJ) and in telomeric protection. Laboratory previously established that resistant CLL cells disclose an up-regulated NHEJ DNA repair and an impaired structure of telomeres. The goal of this thesis was to characterize the biological function(s) of this new form of Ku70. For this purpose we have constructed specific EBV-based vectors (siRNA / cDNA) enabling a simultaneous inhibition of endogenous Ku70 and an expression of different forms (mutated, wild, phospho-mimetic at ser27-33) of Ku70 resistant to siRNA. Thus, we showed: i) a strict co-localisation of phospho-Ku70 with γ-H2AX foci; ii) that DSB induces the phosphorylation of Ku70 within minutes after genotoxic stress in heterodimer complex Ku70/Ku80. This phosphorylation necessitates both the physical interaction and the activity of pS2056-DNA-PKcs and/or ATM, linking phospho-Ku70 to NHEJ-mediated DNA DSB repair; iii) cells expressing mutated A27-A33-Ku70 exhibit a delayed G2/M cell cycle arrest, slower kinetic of DNA repair, lower level of genotoxic stress-induced chromosomal aberrations, and a higher cellular impedance correlated with translocation of transcriptional factor β-catenin from cytoplasmic membrane to the nucleus. Together, these data unveil an involvement of phospho-Ku70 in fast and inaccurate DNA repair; new paradigm for NHEJ regulation and to the control of resistance and maintenance of malignant cells.In parallel, we have initiated experimental approaches to explore other potential roles of phospho-Ku70. Especially, we were interested to determine whether it could play a role in an initiation of cell senescence induced by

DNA-PK/Ku complex binds to latency-associated nuclear antigen and negatively regulates Kaposi's sarcoma-associated herpesvirus latent replication

Energy Technology Data Exchange (ETDEWEB)

Cha, Seho [Department of Life Science, Dongguk Univ-Seoul, Seoul 100-715 (Korea, Republic of); Lim, Chunghun [Department of Biological Sciences, Korea Advanced Institute of Science and Technology, Daejeon 305-701 (Korea, Republic of); Lee, Jae Young [Department of Life Science, Dongguk Univ-Seoul, Seoul 100-715 (Korea, Republic of); Song, Yoon-Jae [Department of Life Science, Kyungwon University, Seongnam-Si, Kyeonggi-Do 461-701 (Korea, Republic of); Park, Junsoo [Division of Biological Science and Technology, Yonsei University, Wonju 220-100 (Korea, Republic of); Choe, Joonho [Department of Biological Sciences, Korea Advanced Institute of Science and Technology, Daejeon 305-701 (Korea, Republic of); Seo, Taegun, E-mail: tseo@dongguk.edu [Department of Life Science, Dongguk Univ-Seoul, Seoul 100-715 (Korea, Republic of)

2010-04-16

During latent infection, latency-associated nuclear antigen (LANA) of Kaposi's sarcoma-associated herpesvirus (KSHV) plays important roles in episomal persistence and replication. Several host factors are associated with KSHV latent replication. Here, we show that the catalytic subunit of DNA protein kinase (DNA-PKcs), Ku70, and Ku86 bind the N-terminal region of LANA. LANA was phosphorylated by DNA-PK and overexpression of Ku70, but not Ku86, impaired transient replication. The efficiency of transient replication was significantly increased in the HCT116 (Ku86 +/-) cell line, compared to the HCT116 (Ku86 +/+) cell line, suggesting that the DNA-PK/Ku complex negatively regulates KSHV latent replication.

Do the metabolites of 6-[F-18]fluoro-L-dopa and of [F-18]fluoro-meta-L-tyrosine contribute to the F-18 accumulation in the human brain?

International Nuclear Information System (INIS)

Firnau, G.; Chirakal, R.; Nahmias, C.; Garnett, E.S.

1990-01-01

The purpose of this study was to determine if the metabolites of 6-[F-18]fluoro-L-dopa (F-dopa) and of [F-18]fluoro-meta-L-tyrosine (FmLtyr) contribute to the accumulation of fluorine-18 in the brain through unspecific retention. PET studies were conducted on a healthy human subject who was treated with both of the radiopharmaceuticals and their labelled metabolites. Results indicated that in contrast to F-dopa, the metabolite of FmLtyr does not 'contaminate' the brain with extraneous fluorine-18

Functional Interplay of the Mre11 Nuclease and Ku in the Response to Replication-Associated DNA Damage ▿

Science.gov (United States)

Foster, Steven S.; Balestrini, Alessia; Petrini, John H. J.

2011-01-01

The Mre11 complex is a central component of the DNA damage response, with roles in damage sensing, molecular bridging, and end resection. We have previously shown that in Saccharomyces cerevisiae, Ku70 (yKu70) deficiency reduces the ionizing radiation sensitivity of mre11Δ mutants. In this study, we show that yKu70 deficiency suppressed the camptothecin (CPT) and methyl methanesulfonate (MMS) sensitivity of nuclease-deficient mre11-3 and sae2Δ mutants in an Exo1-dependent manner. CPT-induced G2/M arrest, γ-H2AX persistence, and chromosome breaks were elevated in mre11-3 mutants. These outcomes were reduced by yKu70 deficiency. Given that the genotoxic effects of CPT are manifest during DNA replication, these data suggest that Ku limits Exo1-dependent double-strand break (DSB) resection during DNA replication, inhibiting the initial processing steps required for homology-directed repair. We propose that Mre11 nuclease- and Sae2-dependent DNA end processing, which initiates DSB resection prevents Ku from engaging DSBs, thus promoting Exo1-dependent resection. In agreement with this idea, we show that Ku affinity for binding to short single-stranded overhangs is much lower than for blunt DNA ends. Collectively, the data define a nonhomologous end joining (NHEJ)-independent, S-phase-specific function of the Ku heterodimer. PMID:21876003

Interplay between Ku and Replication Protein A in the Restriction of Exo1-mediated DNA Break End Resection*

Science.gov (United States)

Krasner, Danielle S.; Daley, James M.; Sung, Patrick; Niu, Hengyao

2015-01-01

DNA double-strand breaks can be eliminated via non-homologous end joining or homologous recombination. Non-homologous end joining is initiated by the association of Ku with DNA ends. In contrast, homologous recombination entails nucleolytic resection of the 5′-strands, forming 3′-ssDNA tails that become coated with replication protein A (RPA). Ku restricts end access by the resection nuclease Exo1. It is unclear how partial resection might affect Ku engagement and Exo1 restriction. Here, we addressed these questions in a reconstituted system with yeast proteins. With blunt-ended DNA, Ku protected against Exo1 in a manner that required its DNA end-binding activity. Despite binding poorly to ssDNA, Ku could nonetheless engage a 5′-recessed DNA end with a 40-nucleotide (nt) ssDNA overhang, where it localized to the ssDNA-dsDNA junction and efficiently blocked resection by Exo1. Interestingly, RPA could exclude Ku from a partially resected structure with a 22-nt ssDNA tail and thus restored processing by Exo1. However, at a 40-nt tail, Ku remained stably associated at the ssDNA-dsDNA junction, and RPA simultaneously engaged the ssDNA region. We discuss a model in which the dynamic equilibrium between Ku and RPA binding to a partially resected DNA end influences the timing and efficiency of the resection process. PMID:26067273

Origin of absorption peaks in reflection loss spectrum in Ku- frequency band of Co-Zr substituted strontium hexaferrites prepared using sucrose precursor

Energy Technology Data Exchange (ETDEWEB)

Narang, Sukhleen Bindra, E-mail: sukhleen2@yahoo.com [Department of Electronics Technology, Guru Nanak Dev University, Amritsar (India); Pubby, Kunal, E-mail: kunalpubby02@gmail.com [Department of Electronics Technology, Guru Nanak Dev University, Amritsar (India); Chawla, S.K., E-mail: sschawla118@gmail.com [Department of Chemistry, Centre for Advanced Studies-I, Guru Nanak Dev University, Amritsar (India); Kaur, Prabhjyot, E-mail: prabhjyot.2525@gmail.com [Department of Chemistry, Centre for Advanced Studies-I, Guru Nanak Dev University, Amritsar (India)

2017-03-15

This study presents the detailed explanation of the factors, contributing towards the absorption peaks in reflection loss spectrum of hexaferrites. Cobalt-Zirconium substituted strontium hexaferrites, synthesized using sucrose precursor sol-gel technique, were analyzed in 12.4–18 GHz frequency range. The concepts of impedance matching through quarter wavelength condition, complex thickness, dielectric phase angle and attenuation constant have been used to determine the location as well as intensity of absorption peaks. This study also demonstrates the potential application of three compositions of this series with doping content (x)==0.0, 0.6 and 0.8 as an effective microwave absorbers in Ku-frequency band. - Highlights: • EM analysis of Sr Hexaferrites in Ku-band. • Factors towards absorption peak intensity & location.

Gözeli yöresindeki (Elazığ meşe (Quercus sp . ormanlarına asılan yapay yuvalardaki böcekçil kuşların kuluçka faaliyetleri

Directory of Open Access Journals (Sweden)

Özden YALÇIN

2015-12-01

Full Text Available Elazığ Orman Bölge Müdürlüğü sınırları içerisinde yer alan Elazığ ili Sivrice ilçesi Gözeli mevkiinde bulunan meşe ormanlarında, 2009-2013 yılları arasında gerçekleştirilen bu çalışma ile farklı bakılara asılan farklı renkteki küçük ve büyük yuva sandıklarında yuva yapan kuş türleri ve bu türlerin kuluçka faaliyetlerinin saptanması amaçlanmıştır. Kuluçkalarını başarı ile tamamlayan kuş türlerinin Otus scops haricindeki türlerin hepsi, hem küçük hem de büyük yuvaları kullanmıştır. Öncelikli yuva tercihleri şu şekilde olmuştur: Parus major küçük yuvaların %66,4’ünde, Cyanistes caeruleus büyük yuvaların %16,3’ünde, Sitta europaea büyük yuvaların %23,2’sinde, Petronia petronia küçük yuvaların %15,2’sinde, Passer domesticus büyük yuvaların %27,9’unda, Otus scops ise sadece büyük yuvaların %7’sinde yuvalanmıştır. Asılan yuvalarda başarılı kuluçka durumunun farklı kuş türlerine göre bakı tercihleri arasında farklılıklar bulunmaktadır. Büyük yuvalarda güney (%39,5, doğu (%34,9, kuzey (%16,3 ve batı (%9,3’dır. Küçük yuvalarda ise güney (%33,2, doğu (%27,2, batı (%20,8 ve kuzey (%18,8’dir.Farklı renklerde asılan kuş yuvalarında başarılı kuluçka yapan kuş türlerinin renk tercihleri değişmektedir. Büyük yuvalarda, Parus major yeşil yuvaları, Cyanistes caeruleus sarı yuvaları, Sitta europaea turuncu yuvaları, Petronia petronia sarı ve mavi yuvaları, Passer domesticus sarı, mavi ve boyanmamış yuvaları daha fazla tercih etmişlerdir. Kuşların yuva tercihinde yuva boyutu, renk ve bakının türler arası farklılık gösterdiği ortaya çıkmıştır. Bir türün daha yoğun bulunduğu alanda, o türe uygun yuva tercihinin gerçekleştirilerek asılması biyolojik mücadele kapsamında daha verimli sonuçlar elde edilmesini sağlayacaktır.

Radiosensitizing activity and pharmacokinetics of multiple dose administered KU-2285 in peripheral nerve tissue in mice

International Nuclear Information System (INIS)

Iwai, Hiroyuki; Matsuno, Etsuko; Sasai, Keisuke; Abe, Mitsuyuki; Shibamoto, Yuta

1994-01-01

In a clinical trial in which a 2-nitroimidazole radiosensitizer was administered repeatedly, the dose-limiting toxicity was found to be peripheral neuropathy. In the present study, the in vivo radiosensitizing activity of KU-2285 in combination with radiation dose fractionation, and the pharmacokinetics of cumulative dosing of KU-2285 in the peripheral nerves were examined. The ability of three nitroimidazoles, misonidazole (MISO), etanidazole (SR-2508) and KU-2285, to sensitize SCCVII tumors to radiation treatment has been compared for drug doses in the range 0-200 mg/kg. Single radiation doses or two different fractionation schedules (6 Gy/fractions x three fractions/48 h or 5 Gy/fractions x five fractions/48 h) were used; the tumor cell survival was determined using an in vivo/in vitro colony assay. The pharmacokinetics in the sciatic nerves were undertaken, when KU-2285 or etanidazole were injected at a dose of 200 mg/kg intravenously one, two, three, or four times at 2-h intervals. At less than 100 mg/kg, KU-2285 sensitized SCCVII tumors more than MISO and SR-2508 by fractionated irradiation. Evaluation of pharmacokinetics in the peripheral nerves showed that the apparent biological half-life of SR-2508 increased with the increases in the number of administrations, whereas that of KU-2285 became shorter. Since most clinical radiotherapy is given in small multiple fractions, KU-2285 appears to be a hypoxic cell radiosensitizer that could be useful in such regimens, and that poses no risk of chronic peripheral neurotoxicity. 12 refs., 5 figs., 1 tab

Restoration of X-ray resistance and V(D)J recombination in mutant cells by Ku cDNA

International Nuclear Information System (INIS)

Smider, V.; Rathmell, W.K.; Chu, G.; Lieber, M.R.

1994-01-01

Three genetic complementation groups of rodent cells are defective for both repair of x-ray-induced double-strand breaks and V(D)J recombination. Cells from one group lack a DNA end-binding activity that is biochemically and antigenically similar to the Ku autoantigen. Transfection of complementary DNA (cDNA) that encoded the 86-kilodalton subunit of Ku rescued these mutant cells for DNA end-binding activity, x-ray resistance, and V(D)J recombination activity. These results establish a role for Ku in DNA repair and recombination. Furthermore, as a component of a DNA-dependent protein kinase, Ku may initiate a signaling pathway induced by DNA damage

Deletion of individual Ku subunits in mice causes an NHEJ-independent phenotype potentially by altering apurinic/apyrimidinic site repair

NARCIS (Netherlands)

Y.J. Choi (Yong Jun); H. Li (Han); M.Y. Son (Mi Young); X.-H. Wang (Xiao-Hong); J.L. Fornsaglio (Jamie L.); R.W. Sobol (Robert W.); M. Lee (Moonsook); J. Vijg (Jan); S. Imholz (Sandra); M.E.T. Dollé (Martijn); H. van Steeg (Harry); E. Reiling (Erwin); P. Hasty (Paul)

2014-01-01

textabstractKu70 and Ku80 form a heterodimer called Ku that forms a holoenzyme with DNA dependent-protein kinase catalytic subunit (DNA-PKCS) to repair DNA double strand breaks (DSBs) through the nonhomologous end joining (NHEJ) pathway. As expected mutating these genes in mice caused a similar DSB

GPM, DPR Level 2A Ku Precipitation V03

Data.gov (United States)

National Aeronautics and Space Administration — The 2AKu algorithm provides precipitation estimates from the Ku radar of the Dual-Frequency Precipitation Radar on the core GPM spacecraft. The product contains one...

Pohon pásového dopravníku pro transport uhlí

OpenAIRE

Kliš, Kamil

2013-01-01

Diplomová práce se zabývá návrhem pohonu pásového dopravníku pro transport uhlí. Práce obsahuje nezbytné výpočty dle norem potřebné k určení vhodných komponentů pásového dopravníku. Cílem diplomové práce bylo navrhnout pohon pásového dopravníku, všech jeho potřebných komponentů včetně návrhem rámu pohonu a vytvoření výkresové dokumentace. This diploma thesis deals with designing a drivetrain for a coal belt conveyor. Thesis contains necessary calculations according to norms needed for dete...

5-(2-18F-fluoroethoxy)-L-tryptophan as a substrate of system L transport for tumor imaging by PET.

Science.gov (United States)

Krämer, Stefanie D; Mu, Linjing; Müller, Adrienne; Keller, Claudia; Kuznetsova, Olga F; Schweinsberg, Christian; Franck, Dominic; Müller, Cristina; Ross, Tobias L; Schibli, Roger; Ametamey, Simon M

2012-03-01

Large neutral l-amino acids are substrates of system L amino acid transporters. The level of one of these, LAT1, is increased in many tumors. Aromatic l-amino acids may also be substrates of aromatic l-amino acid decarboxylase (AADC), the level of which is enhanced in endocrine tumors. Increased amino acid uptake and subsequent decarboxylation result in the intracellular accumulation of the amino acid and its decarboxylation product. (18)F- and (11)C-labeled neutral aromatic amino acids, such as l-3,4-dihydroxy-6-(18)F-fluorophenylalanine ((18)F-FDOPA) and 5-hydroxy-l-[β-(11)C]tryptophan, are thus successfully used in PET to image endocrine tumors. However, 5-hydroxy-l-[β-(11)C]tryptophan has a relatively short physical half-life (20 min). In this work, we evaluated the in vitro and in vivo characteristics of the (18)F-labeled tryptophan analog 5-(2-(18)F-fluoroethoxy)-l-tryptophan ((18)F-l-FEHTP) as a PET probe for tumor imaging. (18)F-l-FEHTP was synthesized by no-carrier-added (18)F fluorination of 5-hydroxy-l-tryptophan. In vitro cell uptake and efflux of (18)F-l-FEHTP and (18)F-FDOPA were studied with NCI-H69 endocrine small cell lung cancer cells, PC-3 pseudoendocrine prostate cancer cells, and MDA-MB-231 exocrine breast cancer cells. Small-animal PET was performed with the respective xenograft-bearing mice. Tissues were analyzed for potential metabolites. (18)F-l-FEHTP specific activity and radiochemical purity were 50-150 GBq/μmol and greater than 95%, respectively. In vitro cell uptake of (18)F-l-FEHTP was between 48% and 113% of added radioactivity per milligram of protein within 60 min at 37°C and was blocked by greater than 95% in all tested cell lines by the LAT1/2 inhibitor 2-amino-2-norboranecarboxylic acid. (18)F-FDOPA uptake ranged from 26% to 53%/mg. PET studies revealed similar xenograft-to-reference tissue ratios for (18)F-l-FEHTP and (18)F-FDOPA at 30-45 min after injection. In contrast to the (18)F-FDOPA PET results, pretreatment with the

A Ku-band magnetically insulated transmission line oscillator with overmoded slow-wave-structure

Science.gov (United States)

Jiang, Tao; He, Jun-Tao; Zhang, Jian-De; Li, Zhi-Qiang; Ling, Jun-Pu

2016-12-01

In order to enhance the power capacity, an improved Ku-band magnetically insulated transmission line oscillator (MILO) with overmoded slow-wave-structure (SWS) is proposed and investigated numerically and experimentally. The analysis of the dispersion relationship and the resonant curve of the cold test indicate that the device can operate at the near π mode of the TM01 mode, which is useful for mode selection and control. In the particle simulation, the improved Ku-band MILO generates a microwave with a power of 1.5 GW and a frequency of 12.3 GHz under an input voltage of 480 kV and input current of 42 kA. Finally, experimental investigation of the improved Ku-band MILO is carried out. A high-power microwave (HPM) with an average power of 800 MW, a frequency of 12.35 GHz, and pulse width of 35 ns is generated under a diode voltage of 500 kV and beam current of 43 kA. The consistency between the experimental and simulated far-field radiation pattern confirms that the operating mode of the improved Ku-band MILO is well controlled in π mode of the TM01 mode. Project supported partly by the National Natural Science Foundation of China (Grant No. 61171021).

Study of sea-surface slope distribution and its effect on radar backscatter based on Global Precipitation Measurement Ku-band precipitation radar measurements

Science.gov (United States)

Yan, Qiushuang; Zhang, Jie; Fan, Chenqing; Wang, Jing; Meng, Junmin

2018-01-01

The collocated normalized radar backscattering cross-section measurements from the Global Precipitation Measurement (GPM) Ku-band precipitation radar (KuPR) and the winds from the moored buoys are used to study the effect of different sea-surface slope probability density functions (PDFs), including the Gaussian PDF, the Gram-Charlier PDF, and the Liu PDF, on the geometrical optics (GO) model predictions of the radar backscatter at low incidence angles (0 deg to 18 deg) at different sea states. First, the peakedness coefficient in the Liu distribution is determined using the collocations at the normal incidence angle, and the results indicate that the peakedness coefficient is a nonlinear function of the wind speed. Then, the performance of the modified Liu distribution, i.e., Liu distribution using the obtained peakedness coefficient estimate; the Gaussian distribution; and the Gram-Charlier distribution is analyzed. The results show that the GO model predictions with the modified Liu distribution agree best with the KuPR measurements, followed by the predictions with the Gaussian distribution, while the predictions with the Gram-Charlier distribution have larger differences as the total or the slick filtered, not the radar filtered, probability density is included in the distribution. The best-performing distribution changes with incidence angle and changes with wind speed.

Trailing (L5) Neptune Trojans: 2004 KV18 and 2008 LC18

International Nuclear Information System (INIS)

Guan Pu; Zhou Liyong; Li Jian

2012-01-01

The population of Neptune Trojans is believed to be bigger than that of Jupiter Trojans and that of asteroids in the main belt, although only eight members of this distant asteroid swarm have been observed up to now. Six leading Neptune Trojans around the Lagrange point L 4 discovered earlier have been studied in detail, but two trailing ones found recently around the L 5 point, 2004 KV18 and 2008 LC18, have not yet been investigated. We report our investigations on the dynamical behaviors of these two new Neptune Trojans. Our calculations show that the asteroid 2004 KV18 is a temporary Neptune Trojan. Most probably, it was captured into the trailing Trojan cloud no earlier than 2.03 × 10 5 yr ago, and it will not maintain this position later than 1.65 × 10 5 yr in the future. Based on the statistics from our orbital simulations, we argue that this object is more like a scattered Kuiper belt object. By contrast, the orbit of 2008 LC18 is much more stable. Among the clone orbits spreading within the orbital uncertainties, a considerable portion of clones may survive on the L 5 tadpole orbits for 4 Gyr. The strong dependence of the stability on the semimajor axis and resonant angle suggests that further observations are badly required to constrain the orbit in the stable region. We also discuss the implications of the existence and dynamics of these two trailing Trojans over the history of the solar system.

The Ku70/80 ring in Non-Homologous End-Joining: easy to slip on, hard to remove.

Science.gov (United States)

Kragelund, Birthe B; Weterings, Eric; Hartmann-Petersen, Rasmus; Keijzers, Guido

2016-01-01

Non-homologous end-joining (NHEJ) is an essential DNA double strand break repair pathway during all cell cycle stages. Deficiency in NHEJ factors can lead to accumulation of unrepaired DNA breaks or faulty DNA repair, which may ultimately result in cell death, senescence or carcinogenesis. The Ku70/80 heterodimer is a key-player in the NHEJ pathway and binds to DNA termini with high affinity, where it helps to protect DNA ends from degradation and to recruit other NHEJ factors required for repair. The mechanism of Ku70/80 detachment from the DNA helix after completion of DNA repair is incompletely understood. Some data suggest that certain DNA repair factors are ubiquitylated and targeted for proteasomal degradation after repair. Recent studies suggest that Ku80 is conjugated to lysine48-linked ubiquitin chains by the Skp1-Cullin-F-box (SCF) complex and/or the RING finger protein 8 (RNF8) ubiquitin-protein ligases, followed by rapid proteasomal degradation. In this review we address the structure and function of the Ku70/80 heterodimer and how ubiquitylation may affect the release of Ku70/80 from chromatin and its subsequent degradation via the ubiquitin-proteasome system.

An integrated Ka/Ku-band payload for personal, mobile and private business communications

Science.gov (United States)

Hayes, Edward J.; Keelty, J. Malcolm

1991-01-01

The Canadian Department of Communications has been studying options for a government-sponsored demonstration payload to be launched before the end of the century. A summary of the proposed system concepts and network architectures for providing an advanced private business network service at Ku-band and personal and mobile communications at Ka-band is presented. The system aspects addressed include coverage patterns, traffic capacity, and grade of service, multiple access options as well as special problems, such as Doppler in mobile applications. Earth terminal types and the advanced payload concept proposed in a feasibility study for the demonstration mission are described. This concept is a combined Ka-band/Ku-band payload which incorporates a number of advanced satellite technologies including a group demodulator to convert single-channel-per-carrier frequency division multiple access uplink signals to a time division multiplex downlink, on-board signal regeneration, and baseband switching to support packet switched data operation. The on-board processing capability of the payload provides a hubless VSAT architecture which permits single-hop full mesh interconnectivity. The Ka-band and Ku-band portions of the payload are fully integrated through an on-board switch, thereby providing the capability for fully integrated services, such as using the Ku-band VSAT terminals as gateway stations for the Ka-band personal and mobile communications services.

Coexposure to benzo[a]pyrene plus UVA induced DNA double strand breaks: visualization of Ku assembly in the nucleus having DNA lesions

International Nuclear Information System (INIS)

Toyooka, Tatsushi; Ibuki, Yuko; Koike, Manabu; Ohashi, Norio; Takahashi, Sentaro; Goto, Rensuke

2004-01-01

Benzo[a]pyrene (BaP) is a ubiquitous environmental pollutant with potential carcinogenicity. It has been shown that BaP, upon UVA irradiation, synergistically induced oxidative DNA damage, but other DNA damage was not confirmed. In this study, we examined whether coexposure to BaP plus UVA induces double strand breaks (DSBs) using xrs-5 cells, deficient in the repair of DSBs (Ku80 mutant), and whether Ku translocates involving the formation of DSBs. BaP plus UVA had a significant cytotoxic effect on CHO-K1 cells and an even more drastic effect on Ku80-deficient, xrs-5 cells, suggesting that the DSBs were generated by coexposure to BaP plus UVA. The DSBs were repaired in CHO-K1 cells within 30 min, but not in xrs-5 cells, indicating the involvement of a non-homologous end joining, which needs Ku proteins. Furthermore, we succeeded in visualizing that Ku80 rapidly assembled to the exposed region, in which DSBs might be generated, and clarified that the presence of both Ku70 and Ku80 was important for their accumulation

Radiation effects on radiation-hardened KU and KS-4V optical fibres

International Nuclear Information System (INIS)

Ivanov, A.A.; Tugarinov, S.N.; Kaschuck, Y.A.; Krasilnikov, A.V.; Bender, S.E.

1999-01-01

The aim of this work was to test the un-pretreated and the hardened (H 2 -loaded and pre-irradiated) KS-4V and KU optical fibres in reactor environment by in-situ measurements of both the radiation-induced loss and the luminescence in the visible spectral region. Both the radio-luminescent and the transmission spectra were in-situ detected during irradiation by charge-coupled-device (CCD) linear detector in the visible spectral region of 400 to 700 nm. The radiation induced loss spectra at the fast neutron fluence of 2*10 6 n/cm 2 shows the hardened, H 2 -loading and pre-irradiating effects in the both KU and KS-4V fibres. KU un-pretreated fibre shows a big radiation absorption band of non-bridging oxygen centered at the wavelength of 630 nm. It appears that the KS-4V hardened fibre has a specific point in the loss spectrum in the vicinity of 460 nm. Other measurements were performed, particularly after reactor shutdown and at 3 different neutron fluences with constant neutron flux after restarting

Hypoxia downregulates Ku70/80 expression in cervical carcinoma tumors

International Nuclear Information System (INIS)

Lara, Pedro Carlos; Lloret, Marta; Clavo, Bernardino; Apolinario, Rosa Maria; Bordon, Elisa; Rey, Agustin; Falcon, Orlando; Alonso, Ana Ruiz; Belka, Claus

2008-01-01

Hypoxia may inhibits the NHEJ DNA repair through downregulating Ku70/80 expression and combined with an increased angiogenesis and altered p53 expression would be responsible for tumor progression in cervical carcinoma

The Ku Protein Complex Interacts with YY1, Is Up-Regulated in Human Heart Failure, and Represses α Myosin Heavy-Chain Gene Expression

Science.gov (United States)

Sucharov, Carmen C.; Helmke, Steve M.; Langer, Stephen J.; Perryman, M. Benjamin; Bristow, Michael; Leinwand, Leslie

2004-01-01

Human heart failure is accompanied by repression of genes such as α myosin heavy chain (αMyHC) and SERCA2A and the induction of fetal genes such as βMyHC and atrial natriuretic factor. It seems likely that changes in MyHC isoforms contribute to the poor contractility seen in heart failure, because small changes in isoform composition can have a major effect on the contractility of cardiac myocytes and the heart. Our laboratory has recently shown that YY1 protein levels are increased in human heart failure and that YY1 represses the activity of the human αMyHC promoter. We have now identified a region of the αMyHC promoter that binds a factor whose expression is increased sixfold in failing human hearts. Through peptide mass spectrometry, we identified this binding activity to be a heterodimer of Ku70 and Ku80. Expression of Ku represses the human αMyHC promoter in neonatal rat ventricular myocytes. Moreover, overexpression of Ku70/80 decreases αMyHC mRNA expression and increases skeletal α-actin. Interestingly, YY1 interacts with Ku70 and Ku80 in HeLa cells. Together, YY1, Ku70, and Ku80 repress the αMyHC promoter to an extent that is greater than that with YY1 or Ku70/80 alone. Our results suggest that Ku is an important factor in the repression of the human αMyHC promoter during heart failure. PMID:15367688

Alterations in cellular energy metabolism associated with the antiproliferative effects of the ATM inhibitor KU-55933 and with metformin.

Directory of Open Access Journals (Sweden)

Mahvash Zakikhani

Full Text Available KU-55933 is a specific inhibitor of the kinase activity of the protein encoded by Ataxia telangiectasia mutated (ATM, an important tumor suppressor gene with key roles in DNA repair. Unexpectedly for an inhibitor of a tumor suppressor gene, KU-55933 reduces proliferation. In view of prior preliminary evidence suggesting defective mitochondrial function in cells of patients with Ataxia Telangiectasia (AT, we examined energy metabolism of cells treated with KU-55933. The compound increased AMPK activation, glucose uptake and lactate production while reducing mitochondrial membrane potential and coupled respiration. The stimulation of glycolysis by KU-55933 did not fully compensate for the reduction in mitochondrial functions, leading to decreased cellular ATP levels and energy stress. These actions are similar to those previously described for the biguanide metformin, a partial inhibitor of respiratory complex I. Both compounds decreased mitochondrial coupled respiration and reduced cellular concentrations of fumarate, malate, citrate, and alpha-ketogluterate. Succinate levels were increased by KU-55933 levels and decreased by metformin, indicating that the effects of ATM inhibition and metformin are not identical. These observations suggest a role for ATM in mitochondrial function and show that both KU-55933 and metformin perturb the TCA cycle as well as oxidative phosphorylation.

Enantioselective synthesis of 6-[18F] fluoro-L-DOPA

International Nuclear Information System (INIS)

Zhang Lan; Tang Ganghua; Zhou Wei; Li Junling; Yin Duanzhi; Wang Yongxian; Tang Xiaolan; Huang Zuhan

2002-01-01

Trimethylammonium veratraldehyde triflate was synthesized and used as a precurser for the synthesis of 6-[ 18 F] Fluoro-L-DOPA by using the chiral phase-transfer catalyst, O-Allyl-N-(9)-anthracenylcinchonidinium bromide which was also synthesized in this study. Based on these, 6-[ 18 F] Fluoro-L-DOPA was prepared with acceptable radiochemical yield (10 ± 3)% in short synthesis time (80 min), with high radiochemical purity, specific activity and chemical purity

Role of Ku80-dependent end-joining in delayed genomic instability in mammalian cells surviving ionizing radiation

International Nuclear Information System (INIS)

Suzuki, Keiji; Kodama, Seiji; Watanabe, Masami

2010-01-01

Ionizing radiation induces delayed destabilization of the genome in the progenies of surviving cells. This phenomenon, which is called radiation-induced genomic instability, is manifested by delayed induction of radiation effects, such as cell death, chromosome aberration, and mutation in the progeny of cells surviving radiation exposure. Previously, there was a report showing that delayed cell death was absent in Ku80-deficient Chinese hamster ovary (CHO) cells, however, the mechanism of their defect has not been determined. We found that delayed induction of DNA double strand breaks and chromosomal breaks were intact in Ku80-deficient cells surviving X-irradiation, whereas there was no sign for the production of chromosome bridges between divided daughter cells. Moreover, delayed induction of dicentric chromosomes was significantly compromised in those cells compared to the wild-type CHO cells. Reintroduction of the human Ku86 gene complimented the defective DNA repair and recovered delayed induction of dicentric chromosomes and delayed cell death, indicating that defective Ku80-dependent dicentric induction was the cause of the absence of delayed cell death. Since DNA-PKcs-defective cells showed delayed phenotypes, Ku80-dependent illegitimate rejoining is involved in delayed impairment of the integrity of the genome in radiation-survived cells.

Role of Ku80-dependent end-joining in delayed genomic instability in mammalian cells surviving ionizing radiation

Energy Technology Data Exchange (ETDEWEB)

Suzuki, Keiji, E-mail: kzsuzuki@nagasaki-u.ac.jp [Course of Life Sciences and Radiation Research, Graduate School of Biomedical Sciences, Nagasaki University, 1-12-4 Sakamoto, Nagasaki 852-8523 (Japan); Kodama, Seiji [Research Institute for Advanced Science and Technology, Osaka Prefecture University, 1-2 Gakuen-machi, Sakai 599-8570 (Japan); Watanabe, Masami [Kyoto University Research Reactor Institute, Kumatori-cho Sennan-gun, Osaka 590-0494 (Japan)

2010-01-05

Ionizing radiation induces delayed destabilization of the genome in the progenies of surviving cells. This phenomenon, which is called radiation-induced genomic instability, is manifested by delayed induction of radiation effects, such as cell death, chromosome aberration, and mutation in the progeny of cells surviving radiation exposure. Previously, there was a report showing that delayed cell death was absent in Ku80-deficient Chinese hamster ovary (CHO) cells, however, the mechanism of their defect has not been determined. We found that delayed induction of DNA double strand breaks and chromosomal breaks were intact in Ku80-deficient cells surviving X-irradiation, whereas there was no sign for the production of chromosome bridges between divided daughter cells. Moreover, delayed induction of dicentric chromosomes was significantly compromised in those cells compared to the wild-type CHO cells. Reintroduction of the human Ku86 gene complimented the defective DNA repair and recovered delayed induction of dicentric chromosomes and delayed cell death, indicating that defective Ku80-dependent dicentric induction was the cause of the absence of delayed cell death. Since DNA-PKcs-defective cells showed delayed phenotypes, Ku80-dependent illegitimate rejoining is involved in delayed impairment of the integrity of the genome in radiation-survived cells.

Návrh zásobníku na sypký vápenný hydrát

OpenAIRE

Perna, Marek

2009-01-01

Tato diplomová práce řeší návrh hlubokého zásobníku na sypký vápenný hydrát pro technologická zařízení čistíren odpadních vod. Je zde proveden rozbor volby typu a konstrukce zásobníku, návrh rozměrů a pevnostní výpočet zásobníku. Je zde popsána možnost vzniku klenby při vyprazdňování a její potlačení pomocí aktivních a pasivních prvků napomáhající toku. Popis aktivních a pasivních stavů napjatosti materiálu v zásobníku. This diploma thesis is solving systems design of silo for a powdery li...

Loss of MLH1 sensitizes colon cancer cells to DNA-PKcs inhibitor KU60648.

Science.gov (United States)

Hinrichsen, Inga; Ackermann, Anne; Düding, Tonja; Graband, Annika; Filmann, Natalie; Plotz, Guido; Zeuzem, Stefan; Brieger, Angela

2017-07-01

Germline mutations of MLH1 are responsible for tumor generation in nearly 50% of patients with Lynch Syndrome, and around 15% of sporadic colorectal cancers show MLH1-deficiency due to promotor hypermethylation. Although these tumors are of lower aggressiveness the benefit for these patients from standard chemotherapy is still under discussion. Recently, it was shown that the sensitivity to the DNA-PKcs inhibitor KU60648 is linked to loss of the MMR protein MSH3. However, loss of MSH3 is rather secondary, as a consequence of MMR-deficiency, and frequently detectable in MLH1-deficient tumors. Therefore, we examined the expression of MLH1, MSH2, MSH6, and MSH3 in different MMR-deficient and proficient cell lines and determined their sensitivity to KU60648 by analyzing cell viability and survival. MLH1-dependent ability of double strand break (DSB) repair was monitored after irradiation via γH2AX detection. A panel of 12 colon cancer cell lines, two pairs of cells, where MLH1 knock down was compared to controls with the same genetic background, and one MLH1-deficient cell line where MLH1 was overexpressed, were included. In summary, we found that MLH1 and/or MSH3-deficient cells exhibited a significantly higher sensitivity to KU60648 than MMR-proficient cells and that overexpression of MLH1 in MLH1-deficient cells resulted in a decrease of cell sensitivity. KU60648 efficiency seems to be associated with reduced DSB repair capacity. Since the molecular testing of colon tumors for MLH1 expression is a clinical standard we believe that MLH1 is a much better marker and a greater number of patients would benefit from KU60648 treatment. © 2017 Wiley Periodicals, Inc.

Experimental research on Ku-band magnetically insulated transmission line oscillator

Energy Technology Data Exchange (ETDEWEB)

Jiang, Tao; Zhang, Jiande; He, Juntao; Li, Zhiqiang; Ling, Junpu [College of Optoelectric Science and Engineering, National University of Defense Technology, Hunan 410073 (China)

2015-10-15

An improved Ku-band magnetically insulated transmission line oscillator is proposed and investigated experimentally. In the particle-in-cell simulation, the Ku-band MILO generates the microwave with a power of 1.62 GW and a frequency of 13 GHz at the input voltage of 474 kV. The device is fabricated based on the simulation results, and an experiment system is designed. In the preliminary experiments, output microwave with frequency of 13.02 GHz, power of 150 MW, and pulse width of 17 ns is generated, under the diode voltage of 450 kV. Analysis on the experiment results shows that plasma produced due to the large current hitting to the outside of the collection tank is the essential cause for the low amplitude of the microwave power and short pulse width.

Evaluation of genetic alteration induced by radon gas using the micronucleus test (Tradescantia sp. clone KU-20)

International Nuclear Information System (INIS)

Bruschi, Armando L.; Azevedo, Heliana de; Macacini, Jose F.; Roque, Claudio V.

2011-01-01

The first observations over the existence of radon gas (Rn), initially known as 'thorium emanation', were carried out between the end of 19 th and beginning of 20 th centuries. A result of uranium-238 (U 238 ) radioactive decay, radon is a tasteless, odorless and colorless gas under room temperature, with a 3.825-day half life and particle α emission in its decay, and as final product of its disintegration, the stable lead-206 isotope (Pb 206 ). Being it is the gas with the highest density known, closed and poor ventilated environments are favorable to its accumulation, with its inhalation being the highest health risk. The use of vegetal bioindicators has shown to be excellent on the monitoring of air quality and on mutagenic potential of various pollutants contained in the atmosphere. Within this context, the objective of this study was to evaluate the micronucleus test application potential utilizing the Tradescantia sp. clone KU-20, in order to evaluate genetic alterations induced by radon gas. Stems of Tradescantia sp. clone KU-20, previously immerse in Hoagland solution, were introduced in a radon detection equipment's calibration chamber (Alphaguard), containing radium salt. Afterwards, the accommodated stems were exposed to radon gas (the average radon concentration was 7.639 KBq/m3) for 24 hours. The results demonstrated an increase on micronucleus formation (39.23 + 2.143 MCN/100 tetrads) in stems exposed in relation to the negative control (18.00 + 1.396 MCN/100 tetrads). The difference between the values indicated a significant increase on micronucleus frequency in the inflorescences subjected to radon gas. The presented results demonstrated the micronucleus test application potential using Tradescantia clone KU-20 to evaluate genetic effects induced by radon gas. (author)

Mre11 and Blm-Dependent Formation of ALT-Like Telomeres in Ku-Deficient Ustilago maydis.

Directory of Open Access Journals (Sweden)

Eun Young Yu

2015-10-01

Full Text Available A subset of human cancer cells uses a specialized, aberrant recombination pathway known as ALT to maintain telomeres, which in these cells are characterized by complex aberrations including length heterogeneity, high levels of unpaired C-strand, and accumulation of extra-chromosomal telomere repeats (ECTR. These phenotypes have not been recapitulated in any standard budding or fission yeast mutant. We found that eliminating Ku70 or Ku80 in the yeast-like fungus Ustilago maydis results initially in all the characteristic telomere aberrations of ALT cancer cells, including C-circles, a highly specific marker of ALT. Subsequently the ku mutants experience permanent G2 cell cycle arrest, accompanied by loss of telomere repeats from chromosome ends and even more drastic accumulation of very short ECTRs (vsECTRs. The deletion of atr1 or chk1 rescued the lethality of the ku mutant, and "trapped" the telomere aberrations in the early ALT-like stage. Telomere abnormalities are telomerase-independent, but dramatically suppressed by deletion of mre11 or blm, suggesting major roles for these factors in the induction of the ALT pathway. In contrast, removal of other DNA damage response and repair factors such as Rad51 has disparate effects on the ALT phenotypes, suggesting that these factors process ALT intermediates or products. Notably, the antagonism of Ku and Mre11 in the induction of ALT is reminiscent of their roles in DSB resection, in which Blm is also known to play a key role. We suggest that an aberrant resection reaction may constitute an early trigger for ALT telomeres, and that the outcomes of ALT are distinct from DSB because of the unique telomere nucleoprotein structure.

Mycobacterial UvrD1 is a Ku-dependent DNA helicase that plays a role in multiple DNA repair events, including double-strand break repair.

Science.gov (United States)

Sinha, Krishna Murari; Stephanou, Nicolas C; Gao, Feng; Glickman, Michael S; Shuman, Stewart

2007-05-18

Mycobacterium tuberculosis and other bacterial pathogens have a Ku-dependent nonhomologous end joining pathway of DNA double-strand break repair. Here we identify mycobacterial UvrD1 as a novel interaction partner for Ku in a genome-wide yeast two-hybrid screen. UvrD1 per se is a vigorous DNA-dependent ATPase but a feeble DNA helicase. Ku stimulates UvrD1 to catalyze ATP-dependent unwinding of 3'-tailed DNAs. UvrD1, Ku, and DNA form a stable ternary complex in the absence of ATP. The Ku binding determinants are located in the distinctive C-terminal segment of UvrD1. A second mycobacterial paralog, UvrD2, is a vigorous Ku-independent DNA helicase. Ablation of UvrD1 sensitizes Mycobacterium smegmatis to killing by ultraviolet and ionizing radiation and to a single chromosomal break generated by I-SceI endonuclease. The physical and functional interactions of bacterial Ku and UvrD1 highlight the potential for cross-talk between components of nonhomologous end joining and nucleotide excision repair pathways.

DNA requirements for interaction of the C-terminal region of Ku80 with the DNA-dependent protein kinase catalytic subunit (DNA-PKcs).

Science.gov (United States)

Radhakrishnan, Sarvan Kumar; Lees-Miller, Susan P

2017-09-01

Non-homologous end joining (NHEJ) is the major pathway for the repair of ionizing radiation induced DNA double strand breaks (DSBs) in human cells. Critical to NHEJ is the DNA-dependent interaction of the Ku70/80 heterodimer with the DNA-dependent protein kinase catalytic subunit (DNA-PKcs) to form the DNA-PK holoenzyme. However, precisely how Ku recruits DNA-PKcs to DSBs ends to enhance its kinase activity has remained enigmatic, with contradictory findings reported in the literature. Here we address the role of the Ku80 C-terminal region (CTR) in the DNA-dependent interaction of Ku70/80 with DNA-PKcs using purified components and defined DNA structures. Our results show that the Ku80 CTR is required for interaction with DNA-PKcs on short segments of blunt ended 25bp dsDNA or 25bp dsDNA with a 15-base poly dA single stranded (ss) DNA extension, but this requirement is less stringent on longer dsDNA molecules (35bp blunt ended dsDNA) or 25bp duplex DNA with either a 15-base poly dT or poly dC ssDNA extension. Moreover, the DNA-PKcs-Ku complex preferentially forms on 25 bp DNA with a poly-pyrimidine ssDNA extension.Our work clarifies the role of the Ku80 CTR and dsDNA ends on the interaction of DNA-PKcs with Ku and provides key information to guide assembly and biology of NHEJ complexes. Copyright © 2017 Elsevier B.V. All rights reserved.

Radiosynthesis and biological evaluation of 5-(3-[18F]Fluoropropyloxy)-L-tryptophan for tumor PET imaging

International Nuclear Information System (INIS)

He, Shanzhen; Tang, Ganghua; Hu, Kongzhen; Wang, Hongliang; Wang, Shuxia; Huang, Tingting; Liang, Xiang; Tang, Xiaolan

2013-01-01

Introduction: [ 18 F]FDG PET has difficulty distinguishing tumor from inflammation in the clinic because of the same high uptake in nonmalignant and inflammatory tissue. In contrast, amino acid tracers do not accumulate in inflamed tissues and thus provide an excellent opportunity for their use in clinical cancer imaging. In this study, we developed a new amino acid tracer 5-(3-[ 18 F]Fluoropropyloxy)-L-tryptophan ([ 18 F]-L-FPTP) by two-step reactions and performed its biologic evaluation. Methods: [ 18 F]-L-FPTP was prepared by [ 18 F]fluoropropylation of 5-hydroxy-L-tryptophan disodium salt and purification on C18 cartridges. The biodistribution of [ 18 F]-L-FPTP was determined in normal mice and the incorporation of [ 18 F]-L-FPTP into tissue proteins was investigated. In vitro competitive inhibition experiments were performed with Hepa1-6 hepatoma cell lines. [ 18 F]-L-FPTP PET imaging was performed on tumor-bearing and inflammation mice and compared with [ 18 F]-L-FEHTP PET. Results: The overall uncorrected radiochemical yield of [ 18 F]-L-FPTP was 21.1 ± 4.4% with a synthesis time of 60 min, the radiochemical purity was more than 99%. Biodistribution studies demonstrate high uptake of [ 18 F]-L-FPTP in liver, kidney, pancreas, and blood at the early phase, and fast clearance in most tissues over the whole observed time. The uptake studies in Hepa1-6 cells suggest that [ 18 F]-L-FPTP is transported by the amino acid transport system B 0,+ , LAT2 and ASC. [ 18 F]-L-FPTP displays good stability and is not incorporated into proteins in vitro. PET imaging shows that [ 18 F]-L-FPTP can be a better potential PET tracer for differentiating tumor from inflammation than [ 18 F]FDG and 5-(3-[ 18 F]fluoroethyloxy)-L-tryptophan ([ 18 F]-L-FEHTP), with high [ 18 F]-L-FPTP uptake ratio (2.53) of tumor to inflammation at 60 min postinjection. Conclusions: Using [ 18 F]fluoropropyl derivatives as intermediates, the new tracer [ 18 F]-L-FPTP was achieved with good yield and

Isolation of eukaryotic ribosomal proteins. Purification and characterization of 60 S ribosomal subunit proteins L3, L6, L7', L8, L10, L15, L17, L18, L19, L23', L25, L27', L28, L29, L31, L32, L34, L35, L36, L36', and L37'.

Science.gov (United States)

Tsurugi, K; Collatz, E; Todokoro, K; Wool, I G

1977-06-10

The proteins of the large subunit of rat liver ribosomes were separated into seven groups by stepwise elution from carboxymethylcellulose with LiCl at pH 6.5. Twenty-one proteins (L3, L6, L7', L8, L10, L15, L17, L18, L19, L23', L25, L27', L28, L29, L31, L32, L34, L35, L36, L36', and L37') were isolated from three groups (C60, E60, and F60) by ion exchange chromatography on carboxymethycellulose and by filtration through Sephadex. The amount of protein obtained varied from 0.3 to 25 mg. Nine of the proteins (L6, L8, L18, L27', L28, L29, L34, L36, and L36') had no detectable contamination: the impurities in the others were no greater than 9%. The molecular weight of the proteins was estimated by polyacrylamide gel electrophoresis in sodium dodecyl sulfate; the amino acid composition was determined.

Apigenin induces apoptosis by targeting inhibitor of apoptosis proteins and Ku70–Bax interaction in prostate cancer

Science.gov (United States)

Shukla, Sanjeev; Fu, Pingfu; Gupta, Sanjay

2014-01-01

Dysfunction of the apoptotic pathway in prostate cancer cells confers apoptosis resistance towards various therapies. A novel strategy to overcome resistance is to directly target the apoptotic pathway in cancer cells. Apigenin, an anticancer agent, selectively toxic to cancer cells induces cell cycle arrest and apoptosis through mechanisms which are not fully explored. In the present study we provide novel insight into the mechanisms of apoptosis induction by apigenin. Treatment of androgen-refractory human prostate cancer PC-3 and DU145 cells with apigenin resulted in dose-dependent suppression of XIAP, c-IAP1, c-IAP2 and survivin protein levels. Apigenin treatment resulted in significant decrease in cell viability and apoptosis induction with the increase of cytochrome C in time-dependent manner. These effects of apigenin were accompanied by decrease in Bcl-xL and Bcl-2 and increase in the active form of Bax protein. The apigenin-mediated increase in Bax was due to dissociation of Bax from Ku70 which is essential for apoptotic activity of Bax. Apigenin treatment resulted in the inhibition of class I histone deacetylases and HDAC1 protein expression, thereby increasing the acetylation of Ku70 and the dissociation of Bax resulting in apoptosis of cancer cells. Furthermore, apigenin significantly reduced HDAC1 occupancy at the XIAP promoter, suggesting that histone deacetylation might be critical for XIAP downregulation. These results suggest that apigenin targets inhibitor of apoptosis proteins and Ku70–Bax interaction in the induction of apoptosis in prostate cancer cells and in athymic nude mouse xenograft model endorsing its in vivo efficacy. PMID:24563225

Oxidative DNA Damage in Neurons: Implication of Ku in Neuronal Homeostasis and Survival

Directory of Open Access Journals (Sweden)

Daniela De Zio

2012-01-01

Full Text Available Oxidative DNA damage is produced by reactive oxygen species (ROS which are generated by exogenous and endogenous sources and continuously challenge the cell. One of the most severe DNA lesions is the double-strand break (DSB, which is mainly repaired by nonhomologous end joining (NHEJ pathway in mammals. NHEJ directly joins the broken ends, without using the homologous template. Ku70/86 heterodimer, also known as Ku, is the first component of NHEJ as it directly binds DNA and recruits other NHEJ factors to promote the repair of the broken ends. Neurons are particularly metabolically active, displaying high rates of transcription and translation, which are associated with high metabolic and mitochondrial activity as well as oxygen consumption. In such a way, excessive oxygen radicals can be generated and constantly attack DNA, thereby producing several lesions. This condition, together with defective DNA repair systems, can lead to a high accumulation of DNA damage resulting in neurodegenerative processes and defects in neurodevelopment. In light of recent findings, in this paper, we will discuss the possible implication of Ku in neurodevelopment and in mediating the DNA repair dysfunction observed in certain neurodegenerations.

Superconducting magnet for a Ku-band maser.

Science.gov (United States)

Berwin, R.; Wiebe, E.; Dachel, P.

1972-01-01

A superconducting magnet to provide a uniform magnetic field of up to 8000 G in a 1.14-cm gap for the 15.3-GHz (Ku-band) traveling wave maser is described. The magnet operates in a persistent mode in the vacuum environment of a closed-cycle helium refrigerator (4.5 K). The features of a superconducting switch, which has both leads connected to 4.5 K heat stations and thereby does not receive heat generated by the magnet charging leads, are described.

DASCH ON KU Cyg: A ∼ 5 YEAR DUST ACCRETION EVENT IN ∼ 1900

International Nuclear Information System (INIS)

Tang Sumin; Grindlay, Jonathan; Los, Edward; Servillat, Mathieu

2011-01-01

KU Cyg is an eclipsing binary consisting of an F-type star accreting through a large accretion disk from a K5III red giant. Here we present the discovery of a 5 year dip around 1900 found from its 100 year DASCH light curve. It showed a ∼0.5 mag slow fading from 1899 to 1903 and brightened back around 1904 on a relatively shorter timescale. The light curve shape of the 1899-1904 fading-brightening event differs from the dust production and dispersion process observed in R Coronae Borealis stars, which usually has a faster fading and slower recovery, and for KU Cyg is probably related to the accretion disk surrounding the F star. The slow fading in KU Cyg is probably caused by increases in dust extinction in the disk, and the subsequent quick brightening may be due to the evaporation of dust transported inward through the disk. The extinction excess which caused the fading may arise from increased mass transfer rate in the system or from dust clump ejections from the K giant.

Characterization of the roles of the catalytic domains of Mycobacterium tuberculosis ligase D in Ku-dependent error-prone DNA end joining.

Science.gov (United States)

Wright, Douglas; DeBeaux, Austin; Shi, Runhua; Doherty, Aidan J; Harrison, Lynn

2010-09-01

We previously established an Escherichia coli strain capable of re-circularizing linear plasmid DNA by expressing the Mycobacterium tuberculosis Ku (Mt-Ku) and Mycobacterium tuberculosis ligase D (Mt-LigD) proteins from the E.coli chromosome. Repair was predominately mutagenic due to deletions at the termini. We hypothesized that these deletions could be due to a nuclease activity of Mt-LigD that was previously detected in vitro. Mt-LigD has three domains: an N-terminal polymerase domain (PolDom), a central domain with 3'-phosphoesterase and nuclease activity and a C-terminal ligase domain (LigDom). We generated bacterial strains expressing Mt-Ku and mutant versions of Mt-LigD. Plasmid re-circularization experiments in bacteria showed that the PolDom alone had no re-circularization activity. However, an increase in the total and accurate repair was found when the central domain was deleted. This provides further evidence that this central domain does have nuclease activity that can generate deletions during repair. Deletion of only the PolDom of Mt-LigD resulted in a complete loss of accurate repair and a significant reduction in total repair. This is in agreement with published in vitro work indicating that the PolDom is the major Mt-Ku-binding site. Interestingly, the LigDom alone was able to re-circularize plasmid DNA but only in an Mt-Ku-dependent manner, suggesting a potential second site for Ku-LigD interaction. This work has increased our understanding of the mutagenic repair by Mt-Ku and Mt-LigD and has extended the in vitro biochemical experiments by examining the importance of the Mt-LigD domains during repair in bacteria.

Variabilní článkový dopravník

OpenAIRE

Trávníček, Jiří

2009-01-01

Tato diplomová práce se zabývá návrhem konstrukce variabilního článkového dopravníku pro přepravu kusových nákladů. Vzhledem k požadavku minimální ceny, byla snaha použít co nejvíce nakupovaných dílů a součástí. Článkový řetěz a ostatní atypické části dopravníku bylo nutné navrhnout. Návrh byl proveden na základě výpočtů s následnou pevnostní a deformační kontrolou. This thesis deals with construction proposal of variable sectional conveyer for lump loads transportation. With regard to req...

Defense AT&L (Volume 35, Number 4, July-August 2006)

National Research Council Canada - National Science Library

2006-01-01

...: Project Management in Afghanistan," by Lt. Col. William T. Cooley, et al. -- Successful rebuilding of the Afghan National Army and Afghan National Police is critical to long-term U.S. security...

Comparative assessment of 6-[18 F]fluoro-L-m-tyrosine and 6-[18 F]fluoro-L-dopa to evaluate dopaminergic presynaptic integrity in a Parkinson's disease rat model.

Science.gov (United States)

Becker, Guillaume; Bahri, Mohamed Ali; Michel, Anne; Hustadt, Fabian; Garraux, Gaëtan; Luxen, André; Lemaire, Christian; Plenevaux, Alain

2017-05-01

Because of the progressive loss of nigro-striatal dopaminergic terminals in Parkinson's disease (PD), in vivo quantitative imaging of dopamine (DA) containing neurons in animal models of PD is of critical importance in the preclinical evaluation of highly awaited disease-modifying therapies. Among existing methods, the high sensitivity of positron emission tomography (PET) is attractive to achieve that goal. The aim of this study was to perform a quantitative comparison of brain images obtained in 6-hydroxydopamine (6-OHDA) lesioned rats using two dopaminergic PET radiotracers, namely [ 18 F]fluoro-3,4-dihydroxyphenyl-L-alanine ([ 18 F]FDOPA) and 6-[ 18 F]fluoro-L-m-tyrosine ([ 18 F]FMT). Because the imaging signal is theoretically less contaminated by metabolites, we hypothesized that the latter would show stronger relationship with behavioural and post-mortem measures of striatal dopaminergic deficiency. We used a within-subject design to measure striatal [ 18 F]FMT and [ 18 F]FDOPA uptake in eight partially lesioned, eight fully lesioned and ten sham-treated rats. Animals were pretreated with an L-aromatic amino acid decarboxylase inhibitor. A catechol-O-methyl transferase inhibitor was also given before [ 18 F]FDOPA PET. Quantitative estimates of striatal uptake were computed using conventional graphical Patlak method. Striatal dopaminergic deficiencies were measured with apomorphine-induced rotations and post-mortem striatal DA content. We observed a strong relationship between [ 18 F]FMT and [ 18 F]FDOPA estimates of decreased uptake in the denervated striatum using the tissue-derived uptake rate constant K c . However, only [ 18 F]FMT K c succeeded to discriminate between the partial and the full 6-OHDA lesion and correlated well with the post-mortem striatal DA content. This study indicates that the [ 18 F]FMT could be more sensitive, with respect of [ 18 F]FDOPA, to investigate DA terminals loss in 6-OHDA rats, and open the way to in vivo L

Synthesis of 2-[18F]fluoro-L-tyrosine via regiospecific fluoro-de-stannylation

International Nuclear Information System (INIS)

Hess, E.; Sichler, S.; Kluge, A.; Coenen, H.H.

2002-01-01

2-[ 18 F]Fluoro-L-tyrosine is a fluorine labelled amino acid, known to be incorporated into newly synthesised proteins, rendering it a potentially suitable tracer to image protein metabolism in vivo using positron emission tomography. For the electrophilic preparation of 2-[ 18 F]fluoro-L-tyrosine three protected 2-trialkylstannyl tyrosine derivatives have been synthesised for the first time as precursors. While O,N-di-Boc-2-triethylstannyl-L-tyrosine ethylester has proved to be suitable as precursor for radiosynthesis, imidazolidinon-derivatives of 2-triaklylstannyl tyrosine have not because of difficult fast hydrolysis of a phenolic O-methyl protective group. The di-Boc-tin derivative of tyrosine ethylester readily reacted with [ 18 F]F 2 , which was prepared via the 18 O(p,n) 18 F nuclear reaction. 2-[ 18 F]Fluoro-L-tyrosine was isolated after full deprotection with aqueous hydrobromic acid and HPLC purification with activities of 1.41±0.32 GBq. The isomeric and enantiomeric purity is high (both >99%). The preparation procedure is facile and easy to automate. The chemical yields of this fluoro-de-stannylation reaction as well as of the synthesis of 6-[ 18 F]fluoro-L-dopa, determined with an analogous precursor and non-radioactive fluorine under identical conditions, amounted to 42.7±1.6% and 60.2±2.8%, respectively

Oil Slick Observation at Low Incidence Angles in Ku-Band

Science.gov (United States)

Panfilova, M. A.; Karaev, V. Y.; Guo, Jie

2018-03-01

On the 20 April 2010 the oil platform Deep Water Horizon in the Gulf of Mexico suffered an explosion during the final phases of drilling an exploratory well. As a result, an oil film covered the sea surface area of several thousand square kilometers. In the present paper the data of the Ku-band Precipitation Radar, which operates at low incidence angles, were used to explore the oil spill event. The two-scale model of the scattering surface was used to describe radar backscatter from the sea surface. The algorithm for retrieval of normalized radar cross section at nadir and the total slope variance of large-scale waves compared to the wavelength of electromagnetic wave (22 mm) was developed for the Precipitation Radar swath. It is shown that measurements at low incidence angles can be used for oil spill detection. This is the first time that the dependence of mean square slope of large-scale waves on wind speed has been obtained for oil slicks from Ku-band data, and compared to mean square slope obtained by Cox and Munk from optical data.

'SON-GO-KU' : a dream of automated library

Science.gov (United States)

Sato, Mamoru; Kishimoto, Juji

In the process of automating libraries, the retrieval of books through the browsing of shelves is being overlooked. The telematic library is a document based DBMS which can deliver the content of books by simulating the browsing process. The retrieval actually simulates the process a person would use in selecting a book in a real library, where a visual presentation using a graphic display is substituted. The characteristics of prototype system "Son-Go-Ku" for such retrieval implemented in 1988 are mentioned.

Design of a Ku band miniature multiple beam klystron

Energy Technology Data Exchange (ETDEWEB)

Bandyopadhyay, Ayan Kumar, E-mail: ayan.bandyopadhyay@gmail.com; Pal, Debasish; Kant, Deepender [Microwave Tubes Division, CSIR-CEERI, Pilani, Rajasthan-333031 (India); Saini, Anil; Saha, Sukalyan; Joshi, Lalit Mohan

2016-03-09

The design of a miniature multiple beam klystron (MBK) working in the Ku-band frequency range is presented in this article. Starting from the main design parameters, design of the electron gun, the input and output couplers and radio frequency section (RF-section) are presented. The design methodology using state of the art commercial electromagnetic design tools, analytical formulae as well as noncommercial design tools are briefly presented in this article.

Natural course of sensitization to hen's egg in children not previously exposed to egg ingestion.

Science.gov (United States)

de Boissieu, D; Dupont, C

2006-04-01

Clinical adverse reactions to egg may occur in infants or children who have never eaten egg. They may be sensitized or even react at first egg ingestion. Few studies are available concerning the reality of egg white allergy in such sensitized children, the natural evolution of this condition and the appropriate decisions to make. To analyze the actuality and natural course of egg allergy in children sensitized without previous of hen's egg ingestion. We set up a clinical decision tree based on clinical history and specific egg white IgE to manage patients who had never ingested egg but were sensitized as demonstrated by a positive SPT and report a cohort of 30 such children The mean level of egg white specific IgE at first analysis, i.e. before 12 months, was high, 28.3 KU(A) /L, with a large range, from 0.6 to >100 KU(A) /L, below 6 KU(A) /L in only 8 patients. In 6 children ("no challenge" group), IgE values remained >8 KU(A) /L by the end of the survey and the oral challenge with egg was always denied. Their mean + SD IgE level was at 51.7 + 38 KU(A) /L at 1 year and 19.7 + 13 KU(A) /L at a mean age of 34 + 5 months. All had an associated anaphylactic reaction with milk and 5 were still allergic to milk by the end of the survey. In the remaining 24 infants, egg was given for the first time at a mean age of 30 + 9 months, by error in 4 cases, all exhibiting an immediate reaction, and in a hospital setting in 20, among whom 14 reacted. Among those 18, with a specific IgE level at 9.1 + 10 KU(A) /L at 28 + 9 months, 4 became tolerant between 3 and 4 years, with specific IgE levels below 1.3 KU(A) /L and a 5th one with specific IgE >100 KU(A) /L at 6 months tolerated scrambled eggs at age 7 year, with specific IgE at 2.6 KU(A) /L. In the 6 others, labeled "non allergic", egg white specific IgE levels were significantly lower, whatever the age, than in the "no challenge" group. The age at challenge was 35 + 8 months, with a mean specific IgE level at 1.0 + 0.9 KU

Analysis of metals in asphaltenes of KU-46 by PIXE analysis; Analisis de metales en asfaltenos de crudo mexicano KU-46 por PIXE

Energy Technology Data Exchange (ETDEWEB)

Navidad G, P.; Pina L, L.I.; Lopez M, J.; Ramirez T, J.J.; Aspiazu F, J.A.; Romero G, E.T. [Gerencia de Ciencias Basicas, Instituto Nacional de Investigaciones Nucleares, A.P. 18-1027, 11801 Mexico D.F. (Mexico)

2002-07-01

The content of metals of the asphaltenes obtained from the KU-46 mexican crude with n-heptane was evaluated. The found metals in higher concentration are transition metals as well as the vanadium, nickel, copper and zinc. Moreover the sulfur in high concentrations was quantified. The metallic content of the asphaltenes revealed that the crude contains a lower quantity of metals unlike the vacuum residue previously analysed. (Author)

Enantioselective synthesis of no-carrier added (NCA) 6-[18F]Fluoro-L-Dopa

International Nuclear Information System (INIS)

Duanzhi Yin; Lan Zhang; Yongxian Wang; Ganghua Tang; First Military Medical Univ., Guangzhou; Xiaolan Tang

2003-01-01

6-[ 18 F]Fluoro-L-Dopa (6-FDOPA) is the analogue of L-Dopa, the biosynthesis precursor for dopamine. As a PET tracer, it was widely applied for the presynaptic dopamine function studies in human brain. The application of a chiral phase-transfer-catalyst (PTC) in enantioselective synthesis of N.C.A. 6-[ 18 F]Fluoro-L-Dopa has been developed recently. An improved procedure was described. The labeling precursor (6-Trimethylammoniumveratraldehyde Triflate) and PTC (O-Allyl-N-(9)-anthracenylcinchonidinium Bromide) were synthesized. A successful synthesis route was developed for the preparation of 6-[ 18 F]Fluoro-L-Dopa with high radiochemical yields (4-9%, decay uncorrected) and short synthesis time(80min). The radiochemical purity was over 99% and no D-isomer was detected by HPLC analysis using a chiral mobile phase. (author)

Wideband Array for C, X, and Ku-Band Applications with 5.3:1 Bandwidth

Science.gov (United States)

Novak, Markus H.; Volakis, John L.; Miranda, Felix A.

2015-01-01

Planar arrays that exploit strong intentional coupling between elements have allowed for very wide bandwidths in low-profile configurations. However, such designs also require complex impedance matching networks that must also be very compact. For many space applications, typically occurring at C-, X-, Ku-, and most recently at Ka-band, such designs require specialized and expensive fabrication techniques. To address this issue, a novel ultra-wideband array is presented, using a simplified feed network to reduce fabrication cost. The array operates from 3.5-18.5 GHz with VSWR less than 2.4 at broadside, and is of very low profile, having a total height of lambda/10 at the lowest frequency of operation. Validation is provided using a 64-element prototype array, fabricated using common Printed Circuit Board (PCB) technology. The low size, weight, and cost of this array make it attractive for space-borne applications.

Kuřim–the largest small town in the South-Moravian Region (Czechia)

Czech Academy of Sciences Publication Activity Database

Vaishar, Antonín

2015-01-01

Roč. 8, č. 8 (2015), s. 135-147 ISSN 2084-5456 Institutional support: RVO:68145535 Keywords : small town * suburbanization * Kuřim Subject RIV: DE - Earth Magnetism, Geodesy, Geography http://annalesgeo.up.krakow.pl/article/view/2839/2502

Characterization of 5-(2- 18F-fluoroethoxy)-L-tryptophan for PET imaging of the pancreas

OpenAIRE

Abbas, Ahmed; Beamish, Christine; McGirr, Rebecca; Demarco, John; Cockburn, Neil; Krokowski, Dawid; Lee, Ting-Yim; Kovacs, Michael; Hatzoglou, Maria; Dhanvantari, Savita

2016-01-01

Purpose: In diabetes, pancreatic beta cell mass declines significantly prior to onset of fasting hyperglycemia. This decline may be due to endoplasmic reticulum (ER) stress, and the system L amino acid transporter LAT1 may be a biomarker of this process. In this study, we used 5-(2- 18F-fluoroethoxy)-L-tryptophan ( 18F-L-FEHTP) to target LAT1 as a potential biomarker of beta cell function in diabetes. Procedures: Uptake of 18F-L-FEHTP was determined in wild-type C57BL/6 mice by ex vivo biodis...

Synergistic effects of methyl methanesulfonate and X rays in inducing somatic mutations in the stamen hairs of Tradescantia clones, KU 27 and BNL 4430

International Nuclear Information System (INIS)

Ichikawa, Sadao; Yamaguchi, Akihiko; Okumura, Mikiko

1993-01-01

Young influorescences of Tradescantia clones KU 27 and BNL 4430, the both of which are blue/pink heterozygotes and have been demonstrated to be highly sensitive to alkylating agents, were exposed either to aqueous solutions of methyl methanesulfonate (MMS) for 16 hr alone (at 0.005 to 0.02% for KU 27 and at 0.005% for BNL 4430) or to acute 150 kVp X rays alone (161 to 531 mGy for Ku 27 and 501 to 976 mGy for BNL 4430), or in combinations (134 to 448 mGy for KU 27 and 458 to 865 mGy for BNL 4430 after the 0.005% MMS treatment). The induced somatic pink mutation frequencies per hair-cell division were studied and compared, and clone BNL 4430 was found to be nearly two times more sensitive to MMS than clone KU 27, while the X-ray-induced mutation frequencies in the latter was about 1.5 times higher than those in the former. The lower sensitivity to MMS of clone KU 27 (as compared with BNL 4430) was nevertheless about 5.6 times higher as compared with the responses of clone BNL 02 to MMS reported earlier, proving the high sensitivities of the two clones used in the present study. Clear synergistic effects of MMS and X rays were observed in the both clones, indicating that the mechanisms of inducing mutations are common at least in part between MMS and X rays. (author)

Vecāku pedagoģiskās kompetences pilnveide pirmsskolas izglītības iestāde

OpenAIRE

Vītola, Aija

2015-01-01

Maģistra darba autore Aija Vītola. Maģistra darba nosaukums „Vecāku pedagoģiskās kompetences pilnveide pirmsskolas izglītības iestādē”. Maģistra darba mērķis: izpētīt vecāku pedagoģiskās kompetences pilnveides iespējas pirmsskolas izglītības iestādē. Darba zinātniski teorētisko daļu veido: 1,5 – 3 gadus vecu bērnu personības attīstības likumsakarības, problēmas, ar kurām vecāki sastopas, bērnam uzsākot gaitas pirmsskolas izglītības iestādē, kompetences jēdziens, būtība, veidi, vecāku ...

Differential gene expression in a DNA double-strand-break repair mutant XRS-5 defective in Ku80. Analysis by cDNA microarray

International Nuclear Information System (INIS)

Chan, John Y.H.; Chen, Lung-Kun; Chang, Jui-Feng

2001-01-01

The ability of cells to rejoin DNA double-strand breaks (DSBs) usually correlates with their radiosensitivity. This correlation has been demonstrated in radiosensitive cells, including the Chinese hamster ovary mutant XRS-5. XRS-5 is defective in a DNA end-binding protein, Ku80, which is a component of a DNA-dependent protein kinase complex used for joining strand breaks. However, Ku80-deficient cells are known to be retarded in cell proliferation and growth as well as other yet to be identified defects. Using custom-made 600-gene cDNA microarray filters, we found differential gene expressions between the wild-type and XRS-5 cells. Defective Ku80 apparently affects the expression of several repair genes, including topoisomerase-I and -IIA, ERCC5, MLH1, and ATM. In contrast, other DNA repair-associated genes, such as GADD45A, EGR1 MDM2 and p53, were not affected. In addition, for large numbers of growth-associated genes, such as cyclins and clks, the growth factors and cytokines were also affected. Down-regulated expression was also found in several categories of seemingly unrelated genes, including apoptosis, angiogenesis, kinase and signaling, phosphatase, stress protein, proto-oncogenes and tumor suppressors, transcription and translation factors. A RT-PCR analysis confirmed that the XRS-5 cells used were defective in Ku80 expression. The diversified groups of genes being affected could mean that Ku80, a multi-functional DNA-binding protein, not only affects DNA repair, but is also involved in transcription regulation. Our data, taken together, indicate that there are specific genes being modulated in Ku80- deficient cells, and that some of the DNA repair pathways and other biological functions are apparently linked, suggesting that a defect in one gene could have global effects on many other processes. (author)

Differential gene expression in a DNA double-strand-break repair mutant XRS-5 defective in Ku80. Analysis by cDNA microarray

Energy Technology Data Exchange (ETDEWEB)

Chan, John Y.H.; Chen, Lung-Kun; Chang, Jui-Feng [National Yang Ming Univ., Taipei, Taiwan (China). Inst. of Radiological Sciences] (and others)

2001-12-01

The ability of cells to rejoin DNA double-strand breaks (DSBs) usually correlates with their radiosensitivity. This correlation has been demonstrated in radiosensitive cells, including the Chinese hamster ovary mutant XRS-5. XRS-5 is defective in a DNA end-binding protein, Ku80, which is a component of a DNA-dependent protein kinase complex used for joining strand breaks. However, Ku80-deficient cells are known to be retarded in cell proliferation and growth as well as other yet to be identified defects. Using custom-made 600-gene cDNA microarray filters, we found differential gene expressions between the wild-type and XRS-5 cells. Defective Ku80 apparently affects the expression of several repair genes, including topoisomerase-I and -IIA, ERCC5, MLH1, and ATM. In contrast, other DNA repair-associated genes, such as GADD45A, EGR1 MDM2 and p53, were not affected. In addition, for large numbers of growth-associated genes, such as cyclins and clks, the growth factors and cytokines were also affected. Down-regulated expression was also found in several categories of seemingly unrelated genes, including apoptosis, angiogenesis, kinase and signaling, phosphatase, stress protein, proto-oncogenes and tumor suppressors, transcription and translation factors. A RT-PCR analysis confirmed that the XRS-5 cells used were defective in Ku80 expression. The diversified groups of genes being affected could mean that Ku80, a multi-functional DNA-binding protein, not only affects DNA repair, but is also involved in transcription regulation. Our data, taken together, indicate that there are specific genes being modulated in Ku80- deficient cells, and that some of the DNA repair pathways and other biological functions are apparently linked, suggesting that a defect in one gene could have global effects on many other processes. (author)

Vecāku audzināšanas stila saistība ar pusaudžu vientulības izjūtu

OpenAIRE

Vlasova, Iveta

2013-01-01

Pētījuma jautājums: Vai starp mātes audzināšanas stilu un vientulības līmeni pusaudžiem pastāv saistība? Pētījuma dalībnieki. Viena izlase, pēc pieejamības principa. Dalībnieku vecums: 12-16 gadi, 31 meitene, 23 zēni. Dzīvojoši pilnās ģimenēs. Pētījuma metode. 1.Lieto, lai noteiktu kopējo vientulības izjūtas līmeni, tika izmantota Vientulības skala (UCLA Loneliness Scale/UCLA LS/, VERSION 3; Russel, D.W. 1996).– visu jautājumu summa. 2.Vecāku audzināšanas stila aptauja (Parental...

The radiosensitizing effect of Ku70/80 knockdown in MCF10A cells irradiated with X-rays and p(66)+Be(40) neutrons.

Science.gov (United States)

Vandersickel, Veerle; Mancini, Monica; Slabbert, Jacobus; Marras, Emanuela; Thierens, Hubert; Perletti, Gianpaolo; Vral, Anne

2010-04-27

A better understanding of the underlying mechanisms of DNA repair after low- and high-LET radiations represents a research priority aimed at improving the outcome of clinical radiotherapy. To date however, our knowledge regarding the importance of DNA DSB repair proteins and mechanisms in the response of human cells to high-LET radiation, is far from being complete. We investigated the radiosensitizing effect after interfering with the DNA repair capacity in a human mammary epithelial cell line (MCF10A) by lentiviral-mediated RNA interference (RNAi) of the Ku70 protein, a key-element of the nonhomologous end-joining (NHEJ) pathway. Following irradiation of control and Ku-deficient cell lines with either 6 MV X-rays or p(66)+Be(40) neutrons, cellular radiosensitivity testing was performed using a crystal violet cell proliferation assay. Chromosomal radiosensitivity was evaluated using the micronucleus (MN) assay. RNAi of Ku70 caused downregulation of both the Ku70 and the Ku80 proteins. This downregulation sensitized cells to both X-rays and neutrons. Comparable dose modifying factors (DMFs) for X-rays and neutrons of 1.62 and 1.52 respectively were obtained with the cell proliferation assay, which points to the similar involvement of the Ku heterodimer in the cellular response to both types of radiation beams. After using the MN assay to evaluate chromosomal radiosensitivity, the obtained DMFs for X-ray doses of 2 and 4 Gy were 2.95 and 2.66 respectively. After neutron irradiation, the DMFs for doses of 1 and 2 Gy were 3.36 and 2.82 respectively. The fact that DMFs are in the same range for X-rays and neutrons confirms a similar importance of the NHEJ pathway and the Ku heterodimer for repairing DNA damage induced by both X-rays and p(66)+Be(40) neutrons. Interfering with the NHEJ pathway enhanced the radiosensitivity of human MCF10A cells to low-LET X-rays and high-LET neutrons, pointing to the importance of the Ku heterodimer for repairing damage induced by both

Antimicrobial photodynamic activity and cytocompatibility of Au25(Capt18 clusters photoexcited by blue LED light irradiation

Directory of Open Access Journals (Sweden)

Miyata S

2017-04-01

Full Text Available Saori Miyata,1 Hirofumi Miyaji,1 Hideya Kawasaki,2 Masaki Yamamoto,2 Erika Nishida,1 Hiroko Takita,3 Tsukasa Akasaka,4 Natsumi Ushijima,3 Toshihiko Iwanaga,5 Tsutomu Sugaya1 1Department of Periodontology and Endodontology, Hokkaido University Graduate School of Dental Medicine, Kita-ku, Sapporo, 2Department of Chemistry and Materials Engineering, Faculty of Chemistry, Materials and Bioengineering, Kansai University, Suita-shi, Osaka, 3Support Section for Education and Research, Hokkaido University Graduate School of Dental Medicine, 4Department of Biomedical, Dental Materials and Engineering, Graduate School of Dental Medicine, Hokkaido University, 5Department of Anatomy, Laboratory of Histology and Cytology, Hokkaido University Graduate School of Medicine, Kita-ku, Sapporo, Japan Abstract: Antimicrobial photodynamic therapy (aPDT has beneficial effects in dental treatment. We applied captopril-protected gold (Au25(Capt18 clusters as a novel photosensitizer for aPDT. Photoexcited Au clusters under light irradiation generated singlet oxygen (1O2. Accordingly, the antimicrobial and cytotoxic effects of Au25(Capt18 clusters under dental blue light-emitting diode (LED irradiation were evaluated. 1O2 generation of Au25(Capt18 clusters under blue LED irradiation (420–460 nm was detected by a methotrexate (MTX probe. The antimicrobial effects of photoexcited Au clusters (0, 5, 50, and 500 µg/mL on oral bacterial cells, such as Streptococcus mutans, Aggregatibacter actinomycetemcomitans, and Porphyromonas gingivalis, were assessed by morphological observations and bacterial growth experiments. Cytotoxicity testing of Au clusters and blue LED irradiation was then performed against NIH3T3 and MC3T3-E1 cells. In addition, the biological performance of Au clusters (500 µg/mL was compared to an organic dye photosensitizer, methylene blue (MB; 10 and 100 µg/mL. We confirmed the 1O2 generation ability of Au25(Capt18 clusters through the fluorescence

A novel coaxial Ku-band transit radiation oscillator without external guiding magnetic field

Energy Technology Data Exchange (ETDEWEB)

Ling, Junpu, E-mail: lingjunpu@163.com; Zhang, Jiande; He, Juntao; Jiang, Tao [College of Photoelectric Science and Engineering, National University of Defense Technology, Changsha 410073 (China)

2014-02-15

A novel coaxial transit radiation oscillator without external guiding magnetic field is designed to generate high power microwave at Ku-band. By using a coaxial structure, the space-charge potential energy is suppressed significantly, that is good for enhancing efficient beam-wave interaction. In order to improve the transmission stability of the unmagnetized intense relativistic electron beam, a Pierce-like cathode is employed in the novel device. By contrast with conventional relativistic microwave generators, this kind of device has the advantages of high stability, non-guiding magnetic field, and high efficiency. Moreover, with the coaxial design, it is possible to improve the power-handing capacity by increasing the radial dimension of the Ku-band device. With a 550 keV and 7.5 kA electron beam, a 1.25 GW microwave pulse at 12.08 GHz has been obtained in the simulation. The power conversion efficiency is about 30%.

PAXX Is an Accessory c-NHEJ Factor that Associates with Ku70 and Has Overlapping Functions with XLF

Directory of Open Access Journals (Sweden)

Satish K. Tadi

2016-10-01

Full Text Available In mammalian cells, classical non-homologous end joining (c-NHEJ is critical for DNA double-strand break repair induced by ionizing radiation and during V(DJ recombination in developing B and T lymphocytes. Recently, PAXX was identified as a c-NHEJ core component. We report here that PAXX-deficient cells exhibit a cellular phenotype uncharacteristic of a deficiency in c-NHEJ core components. PAXX-deficient cells display normal sensitivity to radiomimetic drugs, are proficient in transient V(DJ recombination assays, and do not shift toward higher micro-homology usage in plasmid repair assays. Although PAXX-deficient cells lack c-NHEJ phenotypes, PAXX forms a stable ternary complex with Ku bound to DNA. Formation of this complex involves an interaction with Ku70 and requires a bare DNA extension for stability. Moreover, the relatively weak Ku-dependent stimulation of LIG4/XRCC4 activity by PAXX is unmasked by XLF ablation. Thus, PAXX plays an accessory role during c-NHEJ that is largely overlapped by XLF’s function.

Volba řešitelských strategií v závislosti na věku

Directory of Open Access Journals (Sweden)

Petr Eisenmann

2017-12-01

Full Text Available Příspěvek popisuje experiment, který byl součástí dlouhodobého výzkumu Rozvíjení kultury řešení matematických problémů ve školské praxi. Experiment byl proveden na vzorku celkem 584 respondentů ve věku 11–17 let a mapuje vývoj ve volbě řešitelských strategií matematických úloh u různých věkových skupin žáků. Žákům 6. a 8. ročníku základní školy, I. a III. ročníku střední školy byly předloženy tři úlohy, které se dají efektivně řešit pomocí heuristických strategií. Kromě úspěšnosti řešení úloh byla věnována pozornost také způsobu jejich řešení. Výsledkem experimentu je zjištění, že existují heuristické strategie, které žáci použili při řešení úloh i přesto, že s nimi ve výuce nebyli seznámeni. U některých z nich se jejich výskyt nemění v závislosti na věku.

Serial blood donations for intrauterine transfusions of severe hemolytic disease of the newborn with the use of recombinant erythropoietin in a pregnant woman alloimmunized with anti-Ku.

Science.gov (United States)

Lydaki, Evaggelia; Nikoloudi, Irene; Kaminopetros, Petros; Bolonaki, Irene; Sifakis, Stavros; Kikidi, Katerina; Koumantakis, Evgenios; Foundouli, Kaliopi

2005-11-01

The management of a pregnant woman with the rare Ko phenotype and anti-Ku is a special challenge, because matched blood is extremely rare and the possibility of severe hemolytic disease of the newborn is high. A 30-year-old woman with rare Ko (Knull) phenotype presented at 18 weeks of gestation with positive indirect agglutination test results. She had anti-Ku due to previous blood transfusion, one pregnancy, and two abortions. During this pregnancy, anti-Ku titers ranged from 1024 to 4096. At the 26th week of gestation ultrasound showed a hydropic fetus and urgent intrauterine exchange transfusion was performed with the maternal red blood cells (RBCs). Recombinant human erythropoietin (rHu-EPO) and intravenous (IV) iron were administered to the mother to ensure an adequate supply of matched RBCs for intrauterine transfusions and possible perinatal hemorrhage. Intrauterine transfusions were repeated every 1 to 3 weeks. By 35 weeks 2 days of gestation, the mother had donated 4 units of blood, and four intrauterine transfusions had been performed. Cesarean section was then decided and a healthy male newborn was born. He was treated with phototherapy but without exchange transfusions. By the 15th day of life rHu-EPO was administrated to the newborn because of anemia. The maternal RBCs completely disappeared from the child's blood by Day 100. As shown in this case, treatment with rHu-EPO and IV Fe has effectively increased the mother's capacity to donate RBCs for autologous use and intrauterine transfusions, with no adverse effects to the mother or the child.

Epitope design of L1 protein for vaccine production against Human Papilloma Virus types 16 and 18.

Science.gov (United States)

Baidya, Sunanda; Das, Rasel; Kabir, Md Golam; Arifuzzaman, Md

2017-01-01

Cervical cancer accounts for about two-thirds of all cancer cases linked etiologically to Human Papilloma Virus (HPV). 15 oncogenic HPV types can cause cervical cancer, of which HPV16 and HPV18 combinedly account for about 70% of it. So, effective epitope design for the clinically relevant HPV types 16 and 18 would be of major medical benefit. Here, a comprehensive analysis is carried out to predict the epitopes against HPV types 16 and 18 through "reverse vaccinology" approach. We attempted to identify the evolutionarily conserved regions of major capsid protein (L1) as well as minor capsid protein (L2) of HPV and designed epitopes within these regions. In this study, we analyzed about 49 and 27 sequences of HPV L2 and L1 proteins respectively. Since we found that the intertype variability of L2 is higher than for L1 proteins, our analysis was emphasized on epitopes of L1 of HPV types 16 and 18. We had selected HLA-A*0201, DRB1*1501, DQB1*0602, DRB1*0401 and DQB1*0301 alleles for the prediction of T cell epitopes of L1 of HPV 16 and 18. Finally, we reported that predicted epitope sequences EEYDLQFIFQLCKITLTA, and RHGEEYDLQFIFQLCKITLTA of L1 protein of HPV 16, and LPDPNKF, PETQRLVWAC, PVPGQYDA, YNPETQRLVWAC, DTGYGAMD, PVPGQYDATK, KQDIPKVSAYQYRVFRV, RDNVSVDYKQTQLCI and YSRHVEEYDLQFIF of L1 protein of HPV 18 could be therapeutic tools for vaccine design against HPV.

Analysis of metals in asphaltenes of KU-46 by PIXE analysis

International Nuclear Information System (INIS)

Navidad G, P.; Pina L, L.I.; Lopez M, J.; Ramirez T, J.J.; Aspiazu F, J.A.; Romero G, E.T.

2002-01-01

The content of metals of the asphaltenes obtained from the KU-46 mexican crude with n-heptane was evaluated. The found metals in higher concentration are transition metals as well as the vanadium, nickel, copper and zinc. Moreover the sulfur in high concentrations was quantified. The metallic content of the asphaltenes revealed that the crude contains a lower quantity of metals unlike the vacuum residue previously analysed. (Author)

Isolation and characterization of cDNA encoding the 80-kDa subunit protein of the human autoantigen Ku (p70/p80) recognized by autoantibodies from patients with scleroderma-polymyositis overlap syndrome

International Nuclear Information System (INIS)

Mimori, Tsuneyo; Ohosone, Yasuo; Hama, Nobuaki; Suwa, Akira; Akizuki, Masashi; Homma, Mitsuo; Griffith, A.J.; Hardin, J.A.

1990-01-01

Anti-Ku (p70/p80) autoantibodies in patients with scleroderma-polymyositis overlap syndrome recognize a 70-kDa/80-kDa protein heterodimer which binds to terminal regions of double-stranded DNA. In the present study, the authors isolated full-length cDNAs that encode the 80-kDa Ku subunit. Initial screening of a human spleen cDNA library with anti-Ku antibodies yielded a cDNA of 1.0 kilobase (kb) (termed K71) encoding a portion of the 80-kDa Ku polypeptide (identification based on immunological criteria). In RNA blots, this cDNA hybridized with two mRNAs of 3.4 and 2.6 kb. In vitro transcription and translation experiments produced an immunoprecipitable polypeptide which comigrated with the 80-kDa Ku subunit. The Ku80-6 cDNA proved to be 3304 nucleotides in length, with an additional poly(A) tail, closely approximating the size of the larger mRNA. It contains a single long open reading frame encoding 732 amino acids. The putative polypeptide has a high content of acidic amino acids and a region with periodic repeat of leucine in every seventh position which may form the leucine zipper structure. In genomic DNA blots, probes derived from the opposite ends of cDNA Ku80-6 hybridized with several nonoverlapping restriction fragments from human leukocyte DNA, indicating that the gene encoding the 80-kDa Ku polypeptide is divided into several exons by intervening sequences

Renewal of KU-FEL Facility

CERN Document Server

Kii, Toshiteru; Masuda, Kai; Murakami, Shio; Ohgaki, Hideaki; Yamazaki, Tetsuo; Yoshikawa, Kiyoshi; Zen, Heishun

2004-01-01

Users demands to a high power tunable IR laser are increasing in Japan in energy-related science, such as basic study of high-efficiency solar cells, generation of new energy source of alcohol and/or H2 from polluted gas, and separation of DNA and/or RNA. To satisfy these demands, we decided to renew our FEL facility more user friendly and to operate more flexibly. Construction and fundamental studies on the KU-FEL have been carried out at a building of Institute of Chemical Research where few other accelerators are operating. Therefore, available machine time for our experiments is quite limited. We are now modifying the room by adding concrete walls of 2-m thickness and some space for users will be available. The present FEL system will be moved to the room A photocathode RF-gun system will be nearly added to the system and the present thermionic RF-gun will be used ternatively according to the demands of users. The photocathode material will be Cs2Te. The room with the shielding will be completed in June, ...

Experimental demonstration of a Ku-band radial-line relativistic klystron oscillator based on transition radiation

Science.gov (United States)

Dang, Fangchao; Zhang, Xiaoping; Zhang, Jun; Ju, Jinchuan; Zhong, Huihuang

2017-03-01

We report on a radial-line relativistic klystron oscillator (RL-RKO), which is physically designed to generate gigawatt-level high power microwaves (HPMs) at Ku-band. The 3π/4 mode of a four-gap buncher is selected to highly modulate the radially propagating intense relativistic electron beam (IREB). A three-gap extractor operating at the π mode is employed to extract the radio-frequency energy efficiently. The Ku-band RL-RKO is investigated experimentally on an intense-current electron beam accelerator. The radially propagating IREB is well focused with an axial-width of 2 mm by a radial magnetic field of 0.4 T. Microwaves with a frequency of 14.86 GHz and a power of 1.5 GW are generated, corresponding to an efficiency of 24%, which indicates a significant advance for the research of radial-line HPM sources.

Is a volume of 3.6 mL better than 1.8 mL for inferior alveolar nerve blocks in patients with symptomatic irreversible pulpitis?

Science.gov (United States)

Fowler, Sara; Reader, Al

2013-08-01

The purpose of this retrospective study was to determine the success of the inferior alveolar nerve (IAN) block using either 3.6 mL or 1.8 mL 2% lidocaine with 1:100,000 epinephrine in patients presenting with symptomatic irreversible pulpitis. As part of 7 previously published studies, 319 emergency patients presenting with symptomatic irreversible pulpitis received either a 1.8-mL volume or 3.6-mL volume of 2% lidocaine with 1:100,000 epinephrine in an IAN block. One hundred ninety patients received a 1.8-mL volume, and 129 received a 3.6-mL volume. Endodontic emergency treatment was completed on each subject. Success was defined as the ability to access and instrument the tooth without pain (visual analog scale score of 0) or mild pain (VAS rating ≤54 mm). Success of the 1.8-mL volume was 28%, and for the 3.6-mL volume it was 39%. There was no statistically significant difference between the 2 volumes. In conclusion, for patients presenting with irreversible pulpitis, success was not significantly different between a 3.6-mL volume and a 1.8-mL volume of 2% lidocaine with 1:100,000 epinephrine. The success rates (28%-39%) with either volume were not high enough to ensure complete pulpal anesthesia. Copyright © 2013 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

[Professor Wacław Kuśnierczyk (1908-1997)--Pro Memoria in the century of birthday].

Science.gov (United States)

Brozek, Krzysztof; Kozakiewicz, Jacek; Kierzek, Andrzej

2009-01-01

Wacław Kuśnierczyk was born in 1908 in Sniatyń. He received the degree in medicine at Jan Kazimierz University in Lwów in 1932. He did his PhD degree under Professor Zaleski supervision in 1938 at Jan Kazimierz University. At that time he concentrated his scientific activity on research on tuberculosis. In 1953 he obtained the title of second degree specialist in ear, nose and throat diseases. He became a chief of Otolaryngology at Urban Hospital No 4 in Katowice in 1960. Since then this eminent physician was working on tumours located in upper respiratory tract and the possibility of its endoscopic diagnosis at Silesian Academy of Medicine in Katowice. As one of the first he pointed out the negative influence of smoking cigarettes on cancer of larynx. It was Wacław Kuśnierczyk who implemented new priorities for integrated programs in patient care, research, education and cancer prevention. He has published widely in peer reviewed journals and has edited or contributed to many books. He has given many major lectures and is the recipient of numerous prestigious awards for his scientific accomplishments. The achievement of Professor Kuśnierczyk were the valuable source of information for the physicians. In 1997, on the 31st of January he died in Katowice.

Effect of Ku80 deficiency on mutation frequencies and spectra at a LacZ reporter locus in mouse tissues and cells.

Directory of Open Access Journals (Sweden)

Rita A Busuttil

Full Text Available Non-homologous end joining (NHEJ is thought to be an important mechanism for preventing the adverse effects of DNA double strand breaks (DSBs and its absence has been associated with premature aging. To investigate the effect of inactivated NHEJ on spontaneous mutation frequencies and spectra in vivo and in cultured cells, we crossed a Ku80-deficient mouse with mice harboring a lacZ-plasmid-based mutation reporter. We analyzed various organs and tissues, as well as cultured embryonic fibroblasts, for mutations at the lacZ locus. When comparing mutant with wild-type mice, we observed a significantly higher number of genome rearrangements in liver and spleen and a significantly lower number of point mutations in liver and brain. The reduced point mutation frequency was not due to a decrease in small deletion mutations thought to be a hallmark of NHEJ, but could be a consequence of increased cellular responses to unrepaired DSBs. Indeed, we found a substantial increase in persistent 53BP1 and gammaH2AX DNA damage foci in Ku80-/- as compared to wild-type liver. Treatment of cultured Ku80-deficient or wild-type embryonic fibroblasts, either proliferating or quiescent, with hydrogen peroxide or bleomycin showed no differences in the number or type of induced genome rearrangements. However, after such treatment, Ku80-deficient cells did show an increased number of persistent DNA damage foci. These results indicate that Ku80-dependent repair of DNA damage is predominantly error-free with the effect of alternative more error-prone pathways creating genome rearrangements only detectable after extended periods of time, i.e., in young adult animals. The observed premature aging likely results from a combination of increased cellular senescence and an increased load of stable, genome rearrangements.

[F-18]fluoro-meta-L-tyrosine is a better PET tracer than [F-18]fluoro-L-dopa for the delineation of dopaminergic structures in the human brain

International Nuclear Information System (INIS)

Firnau, G.; Chirakal, R.; Nahmias, C.; Garnett, E.S.

1990-01-01

Fluorine-18 labelled fluoro-m-L-tyrosine (FmLtyr) and fluoro-L-Dopa (F-Dopa) have been synthesized, and the utility of FmLtyr for PET investigations of dopaminergic brain regions has been compared to that of F-dopa. Experimental results from both monkey and human studies indicate that FmLtyr gives better delineation of striatum, and is a better PET tracer than F-dopa

Evaluation of o-[11C]methyl-L-tyrosine and o-[18F]fluoromethyl-L-tyrosine as tumor imaging tracers by PET

International Nuclear Information System (INIS)

Ishiwata, Kiichi; Kawamura, Kazunori; Wang Weifang; Furumoto, Shozo; Kubota, Kazuo; Pascali, Claudio; Bogni, Anna; Iwata, Ren

2004-01-01

We investigated the potential of O-[ 11 C]methyl-L-tyrosine and O-[ 18 F]fluoromethyl-L-tyrosine as positron-emitting tracers for tumor imaging. The two tracers had similar distribution patterns in rats bearing AH109A hepatoma, with pancreas and, on a lesser extent, AH109A showing the highest uptake. Uptake of both tracers in the AH109A and uptake ratios of AH109A-to-tissues (with the exception of AH109A-to-bone) gradually increased for 60 min. O-[ 11 C]methyl-L-tyrosine was metabolically stable, whereas a negligible low amount of metabolites was observed for O-[ 18 F]fluoromethyl-L-tyrosine. Both tracers showed the potential for tumor imaging

GhNAC18 , a novel cotton ( Gossypium hirsutum L.) NAC gene, is ...

African Journals Online (AJOL)

GhNAC18 is a novel NAC gene that was isolated from cotton (Gossypium hirsutum L.). The full-length cDNA was 1511 bp including an open reading frame of 1260 bp in length and encodes a protein of 419 amino acids. With qRT-PCR analysis, GhNAC18 was downregulated during natural and dark-induced senescence, ...

Synthesis of O-(2-[18F]fluoroethyl)-L-tyrosine based on a cartridge purification method

International Nuclear Information System (INIS)

Mueller, Dirk; Klette, Ingo; Kalb, Fabrizia; Baum, Richard P.

2011-01-01

Introduction: O-(2-[ 18 F]fluoroethyl)-L-tyrosine (FET) is widely used as a positron emission tomography tracer for brain tumors. Usually, a high-performance liquid chromatography (HPLC) purification at the end of the two-step synthesis is applied. In this work, we report an automatic radiosynthesis of FET with a purification procedure based on standard cartridges. Methods: O-(2-[ 18 F]fluoroethyl)-L-tyrosine was prepared by [ 18 F]fluoroethylation of L-tyrosine by a two-step synthesis using a modified [ 11 C]methionine module (Nuclear Interface). In the first reaction step, we synthesized [ 18 F]fluoroethyltosylate starting from [ 18 F]fluoride. After a purification step, L-tyrosine was [ 18 F]fluoroethylated with [ 18 F]fluoroethyltosylate. The final reaction mixture was purified by means of solid phase extraction. The FET was trapped on an SCX cartridge, eluted with saline solution and trapped again on an HRX cartridge. For a second purification step, the FET was eluted from the HRX cartridge with ammonium acetate buffer and collected on two SCX cartridges followed by a washing step with water. The final product was eluted with saline solution and neutralised with 450 μl NaHCO 3 solution (8.4%). Results: The synthesis was finished after 50 min and delivered the FET in a range of 3-16 GBq. The synthesis typically yielded 41% (21 experiments) of FET (d.c.) without an HPLC purification step. The radiochemical purity ranged between 97% and 100%. Conclusion: We present a radiosynthesis of FET where the usually used HPLC purification procedure has been substituted by a purification step based on standard cartridges. This method is useful for automatic modules without an expensive HPLC purification unit and for the routine production of FET.

Suppression of the asymmetric competition mode in the relativistic Ku-band coaxial transit-time oscillator

Energy Technology Data Exchange (ETDEWEB)

Ling, Junpu; He, Juntao; Zhang, Jiande; Jiang, Tao; Wang, Lei [College of Optoelectronic Science and Engineering, National University of Defense Technology, Changsha 410073 (China)

2014-10-15

A relativistic Ku-band coaxial transit-time oscillator has been proposed in our previous work. In the experiments, we find that the asymmetric competition mode in the device limits the microwave power with the increase of the input electric power. For solving such a problem, the methods for analysis and suppression of the asymmetric competition mode in the device are investigated theoretically and experimentally. It is shown that the structure and the material of the collector, the concentricity, and the electron emission uniformity play an important part in the suppression of the asymmetric competition mode in the relativistic Ku-band transit-time oscillator. In the subsequent experiments, the asymmetric mode was suppressed effectively. At a low guiding magnetic field of 0.7 T, a microwave pulse with power of 1 GW, frequency of 14.3 GHz close to the simulation one, and efficiency of 20% was generated.

A unified model of the strong and electroweak interactions based on the gauge group SU(18)L x SU(18)R

International Nuclear Information System (INIS)

Kim Il Kang

1986-01-01

On the basis of semi-simple gauge group G=SU(18) L x SU(18) R the unified theory of strong, weak and electromagnetic fields is constructed, and it is shown that the Weinberg angle and the energy of unification are in good agreement with the experimental values. (author)

Synthesis and comparative biological evaluation of L- and D-isomers of {sup 18}F-labeled fluoroalkyl phenylalanine derivatives as tumor imaging agents

Energy Technology Data Exchange (ETDEWEB)

Wang Limin [Department of Chemistry, University of Pennsylvania, Philadelphia, PA 19104 (United States); Lieberman, Brian P.; Ploessl, Karl; Qu Wenchao [Department of Radiology, University of Pennsylvania, Philadelphia, PA 19104 (United States); Kung, Hank F., E-mail: kunghf@gmail.co [Department of Radiology, University of Pennsylvania, Philadelphia, PA 19104 (United States); Department of Pharmacology, University of Pennsylvania, Philadelphia, PA 19104 (United States)

2011-04-15

Introduction: L-Amino acid-based tracers have established their important role as tumor metabolic imaging agents. Recently, a number of studies demonstrated that D-amino acids may have improved imaging properties than their corresponding L-isomers. We synthesized and evaluated the D-isomer of a new phenylalanine derivative, p-(2-[{sup 18}F]fluoroethyl)-phenylalanine ([{sup 18}F]FEP), in comparison to its L-isomer and previously reported the L- and D-isomers of O-(2-[{sup 18}F]fluoroethyl)-tyrosine ([{sup 18}F]FET). Methods: L- and D-Isomers of [{sup 18}F]FET and [{sup 18}F]FEP were successfully synthesized via a rapid and efficient two-step nucleophilic fluorination and deprotection reaction. In vitro studies were carried out in 9L glioma cells. In in vivo studies, Fisher 344 rats bearing the 9L tumor model were used. Results: L- and D-Isomers of {sup 18}F-fluoroalkyl tyrosine and phenylalanine derivatives were efficiently labeled with high enantiomeric purity (>95%), good yield (11-45%) and high specific activity (21-75 GBq/{mu}mol). D-[{sup 18}F]FEP showed a similar linear time-dependent uptake as D-[{sup 18}F]FET, while their corresponding L-isomers had much faster and higher uptake (4.3- to 16.0-fold at maximum uptake). The maximum uptake of the new compounds, L- and D-[{sup 18}F]FEP, was 1.4- and 5.2-fold of that reported for L- and D-[{sup 18}F]FET, respectively. Transport characterization studies indicated that both L- and D-[{sup 18}F]FEP were selective substrates for system L. While L-[{sup 18}F]FEP exhibited preference towards one subtype of system L, LAT1, D-[{sup 18}F]FEP did not exhibit the same preference. Small animal PET imaging studies showed that both L- and D-[{sup 18}F]FEP had higher uptake in 9L tumor compared to surrounding tissues, but D-isomer had lower tumor-to-muscle ratio in comparison with its L-isomer. Conclusion: Both L- and D-[{sup 18}F]FEP are substrates for system L amino acid transporter with different preference toward its

Expression of Mycobacterium tuberculosis Ku and Ligase D in Escherichia coli results in RecA and RecB-independent DNA end-joining at regions of microhomology.

Science.gov (United States)

Malyarchuk, Svitlana; Wright, Douglas; Castore, Reneau; Klepper, Emily; Weiss, Bernard; Doherty, Aidan J; Harrison, Lynn

2007-10-01

Unlike Escherichia coli, Mycobacterium tuberculosis (Mt) expresses a Ku-like protein and an ATP-dependent DNA ligase that can perform non-homologous end-joining (NHEJ). We have expressed the Mt-Ku and Mt-Ligase D in E. coli using an arabinose-inducible promoter and expression vectors that integrate into specific sites in the E. coli chromosome. E. coli strains have been generated that express the Mt-Ku and Mt-Ligase D on a genetic background that is wild-type for repair, or deficient in either the RecA or RecB protein. Transformation of these strains with linearized plasmid DNA containing a 2bp overhang has demonstrated that expression of both the Mt-Ku and Mt-Ligase D is required for DNA end-joining and that loss of RecA does not prevent this double-strand break repair. Analysis of the re-joined plasmid has shown that repair is predominantly inaccurate and results in the deletion of sequences. Loss of RecB did not prevent the formation of large deletions, but did increase the amount of end-joining. Sequencing the junctions has revealed that the majority of the ligations occurred at regions of microhomology (1-4bps), eliminating one copy of the homologous sequence at the junction. The Mt-Ku and Mt-Ligase D can therefore function in E. coli to re-circularize linear plasmid.

Gold electrodes modified with 16H, 18H-dibenzo[c,l]-7,9-dithia-16,18-diazapentacene for electrocatalytic oxidation of NADH

NARCIS (Netherlands)

Rosca, V.; Muresan, L.; Popescu, I.C.; Cristea, C.; Silberg, I.A.

2001-01-01

16H,18H-Dibenzo[c,l]-7,9-dithia-16,18-diazapentacene (DDDP), a new phenothiazine derivative containing two linearly condensed phenothiazine rings, strongly adsorbs on polyoriented gold resulting in a modified electrode with electrocatalytic activity for ß-nicotinamide adenine dinucleotide (NADH)

Differential uptake of [18F]FET and [3H]L-methionine in focal cortical ischemia

International Nuclear Information System (INIS)

Salber, Dagmar; Stoffels, Gabriele; Pauleit, Dirk; Reifenberger, Guido; Sabel, Michael; Shah, Nadim Jon; Hamacher, Kurt; Coenen, Heinz H.; Langen, Karl-Josef

2006-01-01

Amino acids such as [ 11 C-methyl]L-methionine are particularly useful in brain tumor diagnosis, but unspecific uptake (e.g., in cerebral ischemia) has been reported. O-(2-[ 18 F]fluoroethyl)-L-tyrosine ([ 18 F]FET) shows a clinical potential similar to that of L-methionine (MET) in brain tumor diagnosis but is applicable on a wider clinical scale. The aim of this study was to evaluate the uptake of [ 18 F]FET and [ 3 H]MET in focal cortical ischemia in rats by dual-tracer autoradiography. Methods: Focal cortical ischemia was induced in 25 CDF rats using the photothrombosis (PT) model. At different time points up to 6 weeks after the induction of PT, [ 18 F]FET and [ 3 H]MET were injected intravenously. Additionally, contrast-enhanced magnetic resonance imaging (MRI) was performed in 10 animals. One hour after tracer injection, brains were cut in coronal sections and evaluated by dual-tracer autoradiography. Lesion-to-brain (L/B) ratios were calculated by dividing the maximal uptake in the lesion by the mean uptake in the brain. An L/B ratio of >2.0 was considered indicative of pathological uptake. Histological slices were stained by cresyl violet and supplemented by immunostainings for glial fibrillary acidic protein (GFAP) and CD68 in selected cases. Results: A variably increased uptake of both tracers was observed in the PT lesion and its demarcation zone up to 7 days after PT for [ 18 F]FET and up to 6 weeks for [ 3 H]MET. The cutoff level of 2.0 was exceeded in 12/25 animals for [ 18 F]FET and in 18/25 animals for [ 3 H]MET. Focally increased tracer uptake matched contrast enhancement in MRI in 3/10 cases for [ 18 F]FET and in 5/10 cases for [ 3 H]MET. Immunohistochemical staining in lesions with differential uptake of [ 18 F]FET and [ 3 H]MET revealed that selective uptake of [ 18 F]FET was associated with GFAP-positive astrogliosis while selective [ 3 H]MET uptake correlated with CD68-positive macrophage infiltration. Conclusions: [ 18 F]FET, like [ 3 H

Sequence of the amino-terminal region of rat liver ribosomal proteins S4, S6, S8, L6, L7a, L18, L27, L30, L37, L37a, and L39.

Science.gov (United States)

Wittmann-Liebold, B; Geissler, A W; Lin, A; Wool, I G

1979-01-01

The sequence of the amino-terminal region of eleven rat liver ribosomal proteins--S4, S6, S8, L6, L7a, L18, L27, L30, L37a, and L39--was determined. The analysis confirmed the homogeneity of the proteins and suggests that they are unique, since no extensive common sequences were found. The N-terminal regions of the rat liver proteins were compared with amino acid sequences in Saccharomyces cerevisiae and in Escherichia coli ribosomal proteins. It seems likely that the proteins L37 from rat liver and Y55 from yeast ribosomes are homologous. It is possible that rat liver L7a or L37a or both are related to S cerevisiae Y44, although the similar sequences are at the amino-terminus of the rat liver proteins and in an internal region of Y44. A number of similarities in the sequences of rat liver and E coli ribosomal proteins have been found; however, it is not yet possible to say whether they connote a common ancestry.

Does unpaired adenosine-66 from helix II of Escherichia coli 5S RNA bind to protein L18?

DEFF Research Database (Denmark)

Christiansen, J; Douthwaite, S R; Christensen, A

1985-01-01

Adenosine-66 is unpaired within helix II of Escherichia coli 5S RNA and lies in the binding site of ribosomal protein L18. It has been proposed as a recognition site for protein L18. We have investigated further the structural importance of this nucleotide by deleting it. The 5S RNA gene of the rrn...... plasmid derived from pKK3535. Binding studies with protein L18 revealed that the protein bound much more weakly to the mutated 5S RNA. We consider the most likely explanation of this result is that L18 interacts with adenosine-66, and we present a tentative model for an interaction between the unpaired...

Kinetic modelling and optimisation of antimicrobial compound production by Candida pyralidae KU736785 for control of Candida guilliermondii.

Science.gov (United States)

Mewa-Ngongang, Maxwell; du Plessis, Heinrich W; Hutchinson, Ucrecia F; Mekuto, Lukhanyo; Ntwampe, Seteno Ko

2017-06-01

Biological antimicrobial compounds from yeast can be used to address the critical need for safer preservatives in food, fruit and beverages. The inhibition of Candida guilliermondii, a common fermented beverage spoilage organism, was achieved using antimicrobial compounds produced by Candida pyralidae KU736785. The antimicrobial production system was modelled and optimised using response surface methodology, with 22.5 ℃ and pH of 5.0 being the optimum conditions. A new concept for quantifying spoilage organism inhibition was developed. The inhibition activity of the antimicrobial compounds was observed to be at a maximum after 17-23 h of fermentation, with C. pyralidae concentration being between 0.40 and 1.25 × 10 9 CFU ml -1 , while its maximum specific growth rate was 0.31-0.54 h -1 . The maximum inhibitory activity was between 0.19 and 1.08 l contaminated solidified media per millilitre of antimicrobial compound used. Furthermore, the antimicrobial compound formation rate was 0.037-0.086 l VZI ml -1 ACU h -1 , respectively. The response surface methodology analysis showed that the model developed sufficiently described the antimicrobial compound formation rate 1.08 l VZI ml -1 ACU, as 1.17 l VZI ml -1 ACU, predicted under the optimum production conditions.

Faktorová analýza antropometrických charakteristik u mladých plavců ve věku 11 a 12 let Factor analysis of anthropometric characteristics in young swimmers aged 11 and 12

Directory of Open Access Journals (Sweden)

Zofia Ignasiak

2006-02-01

Full Text Available Cílem této práce bylo popsat vybrané somatické charakteristiky typické pro mladé plavce. Faktorová analýza umožnila úměrné snížení somatických ukazatelů a umožnila vypočítat hlavní strukturální faktory typické pro mladé plavce. Do výzkumného souboru bylo zařazeno 80 žáků (11 a 12letých přijatých ke studiu na základní sportovní škole ve Wroclawi. Sledovaní probandi trénovali po dobu 2–3 let a jejich průměrný tréninkový čas byl 12 až 18 hodin týdně. Byly měřeny následující parametry: tělesná výška a hmotnost, délka horních a dolních končetin, obvod stehen, lýtka, paží, předloktí, hrudníku v klidu, hrudníku po nádechu a po výdechu, obvod pasu a boků, šířka ramen, šířka boků, šířka hrudníku, hloubka hrudníku a Rohrerův index. K dosažení cíle této studie byla použita metoda faktorové analýzy. Analýza výsledků ukázala, že pouze některé zvláštnosti mezi sledovanými parametry jsou pro mladé plavce charakteristické. Jsou spojeny do 2 trsů somatických charakteristik: kubický obsah (zahrnuje tělesnou hmotnost, svalstvo, trup a obvod horních a dolních končetin a vertikální rozměr (zahrnuje tělesnou výšku a délku horních a dolních končetin. Tyto parametry signalizují formování postavy typické pro plavce, charakteristické specifickými proporcemi tělesné hmotnosti a výšky, hrudníku a boků a obvykle delšími končetinami. Výsledky naznačují, že antropometrické charakteristiky lze použít pro optimalizaci tréninkového procesu mladých plavců. The aim of this study was to describe the set of somatic characteristics, which significantly discriminate young swimmers. The factor analysis let us reduce the number of somatic traits mostly correlated and to calculate the main structural factors typical for young swimmers. There were 80 pupils (11 and 12 years old from the primary sport school in Wroclaw recruited for the study

Artvin yöresinin iklim, toprak yapısı, orman alanları, ağaç serveti ve ormancılık çalışmalarıyla ilgili genel bir değerlendirme

OpenAIRE

Yüksek, Turan; Ölmez, Zafer

2002-01-01

Çalışma konusu olan Artvin, Kuzeydoğu Karadeniz Bölgesinde yer almaktadır. Artvin ormanları ılıman iklim kuşağından, sert-karasal iklim kuşağına kadar farklı kuşaklarda yayılış göstermektedir. Artvin yöresi 390471 hektar orman alanına sahiptir. Orman alanlarının 276883 hektarı (%70.91’i) doğal ormanlar, 113588 hektarı (% 29.09’u) baltalık ormanlardan oluşmaktadır. Toplam arazinin % 54.77’si ormanlarla kaplıdır. Artvin Orman Bölge Müdürlüğü ormanları, Picea ssp., Pinus ssp., Abies ...

Enterocin X, a novel two-peptide bacteriocin from Enterococcus faecium KU-B5, has an antibacterial spectrum entirely different from those of its component peptides.

Science.gov (United States)

Hu, Chih-Bo; Malaphan, Wanna; Zendo, Takeshi; Nakayama, Jiro; Sonomoto, Kenji

2010-07-01

Enterocin X, composed of two antibacterial peptides (Xalpha and Xbeta), is a novel class IIb bacteriocin from Enterococcus faecium KU-B5. When combined, Xalpha and Xbeta display variably enhanced or reduced antibacterial activity toward a panel of indicators compared to each peptide individually. In E. faecium strains that produce enterocins A and B, such as KU-B5, only one additional bacteriocin had previously been known.

Microwave absorption in X and Ku band frequency of cotton fabric coated with Ni–Zn ferrite and carbon formulation in polyurethane matrix

International Nuclear Information System (INIS)

Gupta, K.K.; Abbas, S.M.; Goswami, T.H.; Abhyankar, A.C.

2014-01-01

The present study highlights various microwave properties, i.e. reflection, transmission, absorption and reflection loss, of the coated cotton fabric [formulation: Ni–Zn ferrite (Ni 0.5 Zn 0.5 Fe 2 O 4 ) and carbon black (acetylene black) at concentrations of 30, 40, 50, 60 and70 g of ferrite and 5 g carbon in each 100 ml polyurethane] evaluated at 8–18 GHz frequency. The uniform density of filling materials in coated fabrics (dotted marks in SEM micrograph) indicates homogeneous dispersion of conducting fillers in polyurethane and the density of filling material cluster increases with increase in ferrite concentration. SEM images also show uniform coating of conducting fillers/resin system over individual fibers and interweave spaces. The important parameters governing the microwave properties of coated fabrics i.e. permittivity and permeability, S-parameters, reflection loss, etc. were studied in a HVS free space microwave measurement system. The lossy character of coated fabric is found to increase with increase of ferrite content; the ferrite content decreases the impedance and increases the permittivity and permeability values. The 1.6–1.8 mm thick coated fabric sample (40 wt% ferrite, 3 wt% carbon and 57 wt% PU) has shown about 40% absorption, 20% transmission and 40% reflectance in X (8.2–12.4 GHz) and Ku (12–18 GHz) frequency bands. The reflection loss at 13.5 GHz has shown the highest peak value (22.5 dB) due to coated sample optical thickness equal to λ/4 and more than 7.5 dB in entire Ku band. Owing to its thin and flexible nature, the coated fabric can be used as apparel in protecting human being from hazardous microwaves and also as radar camouflage covering screen in defense. - Highlights: • Ni–Zn ferrite (Ni 0.5 Zn 0.5 Fe 2 O 4 ) with acetylene black found effective coating for microwave absorption. • Coating formulation containing 40 wt% ferrite, 3 wt% carbon and 57 wt% PU offered 40% absorption, 20% transmission and 40% reflection

Microwave absorption in X and Ku band frequency of cotton fabric coated with Ni–Zn ferrite and carbon formulation in polyurethane matrix

Energy Technology Data Exchange (ETDEWEB)

Gupta, K.K., E-mail: krishna62@rediffmail.com [Defence Materials and Stores Research and Development Establishment, Kanpur PO, GT Road, Kanpur 208013 (India); Abbas, S.M.; Goswami, T.H. [Defence Materials and Stores Research and Development Establishment, Kanpur PO, GT Road, Kanpur 208013 (India); Abhyankar, A.C. [Defence Institute of Advanced Technology( DIAT), Giri Nagar, Pune 411025 (India)

2014-08-01

The present study highlights various microwave properties, i.e. reflection, transmission, absorption and reflection loss, of the coated cotton fabric [formulation: Ni–Zn ferrite (Ni {sub 0.5}Zn{sub 0.5}Fe{sub 2}O{sub 4}) and carbon black (acetylene black) at concentrations of 30, 40, 50, 60 and70 g of ferrite and 5 g carbon in each 100 ml polyurethane] evaluated at 8–18 GHz frequency. The uniform density of filling materials in coated fabrics (dotted marks in SEM micrograph) indicates homogeneous dispersion of conducting fillers in polyurethane and the density of filling material cluster increases with increase in ferrite concentration. SEM images also show uniform coating of conducting fillers/resin system over individual fibers and interweave spaces. The important parameters governing the microwave properties of coated fabrics i.e. permittivity and permeability, S-parameters, reflection loss, etc. were studied in a HVS free space microwave measurement system. The lossy character of coated fabric is found to increase with increase of ferrite content; the ferrite content decreases the impedance and increases the permittivity and permeability values. The 1.6–1.8 mm thick coated fabric sample (40 wt% ferrite, 3 wt% carbon and 57 wt% PU) has shown about 40% absorption, 20% transmission and 40% reflectance in X (8.2–12.4 GHz) and Ku (12–18 GHz) frequency bands. The reflection loss at 13.5 GHz has shown the highest peak value (22.5 dB) due to coated sample optical thickness equal to λ/4 and more than 7.5 dB in entire Ku band. Owing to its thin and flexible nature, the coated fabric can be used as apparel in protecting human being from hazardous microwaves and also as radar camouflage covering screen in defense. - Highlights: • Ni–Zn ferrite (Ni{sub 0.5}Zn{sub 0.5}Fe{sub 2}O{sub 4}) with acetylene black found effective coating for microwave absorption. • Coating formulation containing 40 wt% ferrite, 3 wt% carbon and 57 wt% PU offered 40% absorption, 20

Initial assessment of an airborne Ku-band polarimetric SAR.

Energy Technology Data Exchange (ETDEWEB)

Raynal, Ann Marie; Doerry, Armin Walter

2013-02-01

Polarimetric synthetic aperture radar (SAR) has been used for a variety of dual-use research applications since the 1940s. By measuring the direction of the electric field vector from radar echoes, polarimetry may enhance an analysts understanding of scattering effects for both earth monitoring and tactical surveillance missions. Polarimetry may provide insight into surface types, materials, or orientations for natural and man-made targets. Polarimetric measurements may also be used to enhance the contrast between scattering surfaces such as man-made objects and their surroundings. This report represents an initial assessment of the utility of, and applications for, polarimetric SAR at Ku-band for airborne or unmanned aerial systems.

On the synthesis of radiofluorinated amino acids by isotope exchange based on the example of 6-[{sup 18}F]Fluor-L-DOPA; Zur Synthese radiofluorierter aromatischer Aminosaeuren mittels Isotopenaustausch am Beispiel von 6-[{sup 18}F]Fluor-L-DOPA

Energy Technology Data Exchange (ETDEWEB)

Wagner, F M

2008-06-15

In nuclear medical diagnosis, 6-[{sup 18}F]fluoro-L-3,4-dihydroxyphenylalanine (6-[{sup 18}F]fluoro-LDOPA), an analogue of L-DOPA, is one of the few established radiopharmaceuticals used for the in vivo investigation of the presynaptic dopaminergic metabolism and of some kind of tumours via Positron Emission Tomography (PET). The presently used method of preparation of the radiotracer by electrophilic labelling is limited to low amounts of activity at high costs. Known nucleophilic syntheses, however, result either in insufficient enantiomeric purity or the known multi-step syntheses are hard to automate, due to their complexity. During this work a novel, easy to automate alternative for the preparation of 6-[{sup 18}F]fluoro-L-DOPA, was developed and evaluated, using a direct nucleophilic {sup 18}F-fluorination of a protected amino acid derivative. The resulting product has a very high enantiomeric purity. At first, the general suitability of the (S)-BOC-BMI-derivatives for the synthesis of {sup 18}F-labelled amino acids, used in this work, was investigated using a less complex precursor, which resulted in the amino acid 6-[{sup 18}F]fluoro-L-m-tyrosin via acidic hydrolysis. The preparation of a useful precursor for the nucleophilic {sup 18}F-isotope substitution, namely the (2S,5S)-tert.-butyl- 5-(2-fluoro-5-formylbenzyl)-2-tert.-butyl-3-methyl-4-oxoimidazolidine-1-carboxylate, was investigated in three general different ways. At first it was tried to obtain this product via formylation after coupling with the BOC-BMI, secondly via {alpha},{beta}-dehydro amino acid derivatives and finally via a systematic multi-step synthesis. Only the last mentioned way resulted in a precursor with sufficient purity that could be labelled. The radiochemical yield of the isotopic exchange was about 60 %. In the next step, the presented concept was modified to synthesize a precursor for the preparation of 6-[{sup 18}F]fluoro-L-DOPA. Only a combination of the protecting groups

Characterization of 5-(2-18F-fluoroethoxy-L-tryptophan for PET imaging of the pancreas [version 2; referees: 2 approved

Directory of Open Access Journals (Sweden)

Ahmed Abbas

2016-11-01

Full Text Available Purpose: In diabetes, pancreatic beta cell mass declines significantly prior to onset of fasting hyperglycemia. This decline may be due to endoplasmic reticulum (ER stress, and the system L amino acid transporter LAT1 may be a biomarker of this process. In this study, we used 5-(2-18F-fluoroethoxy-L-tryptophan (18F-L-FEHTP to target LAT1 as a potential biomarker of beta cell function in diabetes. Procedures: Uptake of 18F-L-FEHTP was determined in wild-type C57BL/6 mice by ex vivo biodistribution. Both dynamic and static positron emission tomography (PET images were acquired in wild-type and Akita mice, a model of ER stress-induced diabetes, as well as in mice treated with streptozotocin (STZ. LAT1 expression in both groups of mice was evaluated by immunofluorescence microscopy. Results: Uptake of 18F-L-FEHTP was highest in the pancreas, and static PET images showed highly specific pancreatic signal. Time-activity curves showed significantly reduced 18F-L-FEHTP uptake in Akita mice, and LAT1 expression was also reduced. However, mice treated with STZ, in which beta cell mass was reduced by 62%, showed no differences in 18F-L-FEHTP uptake in the pancreas, and there was no significant correlation of 18F-L-FEHTP uptake with beta cell mass. Conclusions: 18F-L-FEHTP is highly specific for the pancreas with little background uptake in kidney or liver. We were able to detect changes in LAT1 in a mouse model of diabetes, but these changes did not correlate with beta cell function or mass. Therefore, 18F-L-FEHTP PET is not a suitable method for the noninvasive imaging of changes in beta cell function during the progression of diabetes.

Izrada 3D modela kućišta centrifugalne pumpe

OpenAIRE

Hršak, Božidar; Golubić, Stjepan; Carek, Dalibor

2012-01-01

Prikazana je izrada 3D modela kućišta centrifugalne pumpe na temelju postojećeg 2D nacrta gotovog proizvoda primjenom sinkrone tehnologije 3D modeliranja, i reverzibilnog inženjeringa. Na temelju kreiranog 3D modela, predložene su moguće modifikacije postojeće izvedbe proizvoda. Provedene su analize zakrivljenosti površina, Bézierove krivulje modela i 3D geometrije. Prikazana je i mogućnost vizualizacije gotovog 3D modela na Web stranicama u cilju prezentiranja proizvoda budućim kupcima primj...

Enterocin X, a Novel Two-Peptide Bacteriocin from Enterococcus faecium KU-B5, Has an Antibacterial Spectrum Entirely Different from Those of Its Component Peptides▿

Science.gov (United States)

Hu, Chih-Bo; Malaphan, Wanna; Zendo, Takeshi; Nakayama, Jiro; Sonomoto, Kenji

2010-01-01

Enterocin X, composed of two antibacterial peptides (Xα and Xβ), is a novel class IIb bacteriocin from Enterococcus faecium KU-B5. When combined, Xα and Xβ display variably enhanced or reduced antibacterial activity toward a panel of indicators compared to each peptide individually. In E. faecium strains that produce enterocins A and B, such as KU-B5, only one additional bacteriocin had previously been known. PMID:20418437

Pilot Preclinical and Clinical Evaluation of (4S-4-(3-[18F]Fluoropropyl-L-Glutamate (18F-FSPG for PET/CT Imaging of Intracranial Malignancies.

Directory of Open Access Journals (Sweden)

Erik S Mittra

Full Text Available (S-4-(3-[18F]Fluoropropyl-L-glutamic acid (18F-FSPG is a novel radiopharmaceutical for Positron Emission Tomography (PET imaging. It is a glutamate analogue that can be used to measure xC- transporter activity. This study was performed to assess the feasibility of 18F-FSPG for imaging orthotopic brain tumors in small animals and the translation of this approach in human subjects with intracranial malignancies.For the small animal study, GS9L glioblastoma cells were implanted into brains of Fischer rats and studied with 18F-FSPG, the 18F-labeled glucose derivative 18F-FDG and with the 18F-labeled amino acid derivative 18F-FET. For the human study, five subjects with either primary or metastatic brain cancer were recruited (mean age 50.4 years. After injection of 300 MBq of 18F-FSPG, 3 whole-body PET/Computed Tomography (CT scans were obtained and safety parameters were measured. The three subjects with brain metastases also had an 18F-FDG PET/CT scan. Quantitative and qualitative comparison of the scans was performed to assess kinetics, biodistribution, and relative efficacy of the tracers.In the small animals, the orthotopic brain tumors were visualized well with 18F-FSPG. The high tumor uptake of 18F-FSPG in the GS9L model and the absence of background signal led to good tumor visualization with high contrast (tumor/brain ratio: 32.7. 18F-FDG and 18F-FET showed T/B ratios of 1.7 and 2.8, respectively. In the human pilot study, 18F-FSPG was well tolerated and there was similar distribution in all patients. All malignant lesions were positive with 18F-FSPG except for one low-grade primary brain tumor. In the 18F-FSPG-PET-positive tumors a similar T/B ratio was observed as in the animal model.18F-FSPG is a novel PET radiopharmaceutical that demonstrates good uptake in both small animal and human studies of intracranial malignancies. Future studies on larger numbers of subjects and a wider array of brain tumors are planned.ClinicalTrials.gov NCT

EPR study of gamma and neutron irradiation effects on KU1, KS-4V and Infrasil 301 silica glasses

International Nuclear Information System (INIS)

Lagomacini, Juan C.; Bravo, David; Leon, Monica; Martin, Piedad; Ibarra, Angel; Martin, Agustin; Lopez, Fernando J.

2011-01-01

Electron paramagnetic resonance (EPR) studies have been carried out on KU1 and KS-4V high purity quartz glasses and commercial silica Infrasil 301, irradiated with gamma rays up to a dose of 11.6 MGy and neutron fluences of 10 21 and 10 22 n/m 2 . Gamma irradiations produce a much higher concentration of defect centres (mainly E', POR and NBOHC) for KU1 and I301 than for KS-4V silica. In contrast, neutron irradiation at the highest fluence produces similar concentrations in all silica types. These results agree to a good extent with those obtained in previous optical absorption measurements. Moreover, oxygen-related centres (POR and NBOHC) have been well characterized by means of electron paramagnetic resonance.

EPR study of gamma and neutron irradiation effects on KU1, KS-4V and Infrasil 301 silica glasses

Energy Technology Data Exchange (ETDEWEB)

Lagomacini, Juan C., E-mail: jc.lagomacini@uam.es [Dept. Fisica de Materiales, Universidad Autonoma de Madrid, E-28049 Madrid (Spain); Bravo, David [Dept. Fisica de Materiales, Universidad Autonoma de Madrid, E-28049 Madrid (Spain); Leon, Monica; Martin, Piedad; Ibarra, Angel [Materiales para Fusion, CIEMAT, Avda. Complutense 22, E-28040 Madrid (Spain); Martin, Agustin [Dept. Fisica e Instalaciones, ETS Arquitectura UPM, E-28040 Madrid (Spain); Lopez, Fernando J. [Dept. Fisica de Materiales, Universidad Autonoma de Madrid, E-28049 Madrid (Spain)

2011-10-01

Electron paramagnetic resonance (EPR) studies have been carried out on KU1 and KS-4V high purity quartz glasses and commercial silica Infrasil 301, irradiated with gamma rays up to a dose of 11.6 MGy and neutron fluences of 10{sup 21} and 10{sup 22} n/m{sup 2}. Gamma irradiations produce a much higher concentration of defect centres (mainly E', POR and NBOHC) for KU1 and I301 than for KS-4V silica. In contrast, neutron irradiation at the highest fluence produces similar concentrations in all silica types. These results agree to a good extent with those obtained in previous optical absorption measurements. Moreover, oxygen-related centres (POR and NBOHC) have been well characterized by means of electron paramagnetic resonance.

Colour-stability and gloss-retention of silorane and dimethacrylate composites with accelerated aging.

Science.gov (United States)

Furuse, Adilson Y; Gordon, Kathryn; Rodrigues, Flávia P; Silikas, Nick; Watts, David C

2008-11-01

To evaluate the colour-stability and gloss-retention of silorane versus dimethacrylate composites exposed to accelerated aging from daylight radiation. Five disc-shaped specimens of photo-cured resin-composites were prepared and manually polished for each material (Filtek Silorane, Herculite XRV, Tetric Evoceram and QuiXfil). Colour and gloss were evaluated before and after periods (baseline, 24, 72, 120 and 192 h) of accelerated photo-aging in xenon light following ISO 7491:2000. Colour measurements were performed with a colourimeter according to the CIE-Lab colour-space. The colour change (DeltaE) for each time was calculated. The surface gloss was measured using a glossmeter. Results were evaluated using one-way ANOVA and Tukey tests (alpha=0.05). Correlations between logtime, DeltaE and gloss were evaluated using Pearson's correlation (alpha=0.05). Materials generally decreased in L and a and increased in b. The strong exception was Filtek Silorane which maintained a and b. DeltaE was found to be a positive linear function of logtime for all materials. Materials varied in the magnitude and rate of increase of DeltaE with logtime: QuiXfil>Tetric EvoCeram>(Filtek Silorane>or=Herculite XRV). DeltaE remainedGloss was found to be a negative linear function of logtime. Gloss was maximal in the sequence: Filtek Silorane approximately Tetric EvoCeram>Herculite XRV>QuiXfil. Silorane gave the best overall performance in stability over time, compared to a set of representative dimethacrylate composites.

The relation of putamen nucleus 6-[18F]fluoro-L-m-tyrosine uptake to total Unified Parkinson's Disease Rating Scale scores

International Nuclear Information System (INIS)

Buchy, R.

2002-01-01

The contribution of dopaminergic deficiency in the striatum to the severity of locomotor disability in Parkinson's disease has been consistently shown with 6-[ 18 F]fluoro-L-DOPA in positron emission tomography. Recently, 6-[ 18 F]fluoro-L-m-tyrosine, an alternative tracer with similar distribution kinetics has been used to facilitate data analysis. Locomotor disability in Parkinson's disease can be measured using the Unified Parkinson's Disease Rating Scale. The Unified Parkinson's Disease Rating Scale was used in conjunction with 6-[ 18 F]fluoro-L-m-tyrosine -PET to clinically examine a group of five Parkinson's disease patients. An inverse relation similar to that previously demonstrated with 6-[ 18 F]fluoro-L-DOPA was found between the putamen nucleus 6-[ 18 F]fluoro-L-m-tyrosine influx constant and Unified Parkinson's Disease Rating Scale score. This finding suggests that like 6-[ 18 F]fluoro-L-m-tyrosine can be used to accurately measure the degree of locomotor disability caused by Parkinson's disease. (author)

Radiolabelling of isopeptide Nε-(γ-glutamyl)-L-lysine by conjugation with N-succinimidyl-4-[18F]fluorobenzoate

International Nuclear Information System (INIS)

Wuest, F.; Hultsch, C.; Bergmann, R.; Johannsen, B.; Henle, T.

2003-01-01

The isopeptide N ε -(γ-glutamyl)-L-lysine 4 was labelled with 18 F via N-succinimidyl-4-[ 18 F]fluorobenzoate ([ 18 F]SFB). A modified approach for the convenient synthesis of [ 18 F]SFB was used, and [ 18 F]SFB could be obtained in decay-corrected radiochemical yields of 44-53% (n=20) and radiochemical purity >95% within 40 min after EOB. For labelling N ε -(γ-glutamyl)-L-lysine with [ 18 F]SFB the effects of isopeptide concentration, temperature, and pH were studied to determine the optimum reaction conditions. The coupling reaction was shown to be temperature and pH independent while being strongly affected by the isopeptide concentration. Using the optimized labelling conditions, in a typical experiment 1.3 GBq of [ 18 F]SFB could be converted into 447 MBq (46%, decay-corrected) of [ 18 F]fluorobenzoylated isopeptide within 45 min, including HPLC purification

Występowanie i nasilenie zaburzeń lękowych i depresyjnych u kobiet z rakiem piersi przygotowywanych do leczenia chirurgicznego = Incidence and intensification of anxiety and depressive disorders at women with breast cancer prepared for the surgical treatm

Directory of Open Access Journals (Sweden)

Marta Łuczyk

2015-05-01

2 Department of the Internal Medicine with the Unit of Internal Nursing, Department of Health Sciences, Medical University of Lublin   Streszczenie Wstęp. Rozpoznanie choroby nowotworowej piersi wywiera szczególny wpływ na stan psychiczny kobiety. Jedną z negatywnych reakcji emocjonalnych u kobiet po rozpoznaniu choroby nowotworowej są zaburzenia lękowe, którym mogą towarzyszy zaburzenia depresyjne. Cel pracy. Ocena występowania i nasilenia zaburzeń lękowych i depresyjnych wśród kobiet z rakiem piersi oczekujących na zabieg operacyjny. Materiał i metoda. Badania przeprowadzono metodą sondażu diagnostycznego, techniką ankiety z użyciem narzędzi: Szpitalnej Skali Oceny Lęku i Depresji (HADS, Skali wizualno – analogowej zaadoptowanej do oceny lęku, autorskiego kwestionariusza wywiadu. Do badań zakwalifikowano 150 kobiet z rakiem piersi. Wyniki. W grupie chorych z rakiem piersi przygotowywanych do leczenia chirurgicznego u 93 (62,00% osób wystąpiły zaburzenia lękowe, u 24 (19,33% chorych stwierdzono stany graniczne, u 28 kobiet (18,67% nie stwierdzono zaburzeń. Ponad 95% kobiet odczuwało niepokój przed chorobą nowotworową, a 89% badanych deklarowało odczuwanie lęku przed leczeniem chirurgicznym. Stwierdzono występowanie zaburzeń depresyjnych u 24 osób (16,00%, a u 39 (26,00% osób stwierdzono stany graniczne. U 58% (87,00% badanych kobiet nie stwierdzono zaburzeń. Wnioski. U badanych kobiet stwierdzono występowanie zaburzeń lękowych, natomiast w mniejszym stopniu zaobserwowano zaburzenia depresyjne. Prowadzenie badań oceniających występowanie lęku w okresie przedoperacyjnym powinno stać się rutynowym postępowaniem w przygotowaniu chorych do zbiegu operacyjnego. Słowa kluczowe: fobie, zaburzenia lękowe, zaburzenia depresyjne, nowotwory sutka.   Abstract Introduction. Diagnosing cancer of the breast exerts special impact on the mental state of the woman. One of negative emotional reactions at women after diagnosing

Agresijas un vecāku audzināšanas stila saistība jauniešiem no profesionālās vidējās izglītības iestādēm

OpenAIRE

Stikāne, Austra

2012-01-01

Pētījuma jautājumi ir vai pastāv saistība starp agresijas rādītājiem un vecāku audzināšanas stilu profesionālās vidējās izglītības iestāžu audzēkņiem, kuri ikdienā dzīvo ar vecākiem un audzēkņiem, kuri ikdienā nedzīvo ģimenē, kā arī vai pastāv atšķirības agresijas skalās starp jauniešiem, kuri dzīvo ar vecākiem ikdienā un jauniešiem, kuri ikdienā nedzīvo ar vecākiem. Pētījumā piedalījās 95 respondenti (55 studenti, kuri ikdienā dzīvo ar vecākiem, 40 studenti, kuri ikdienā nedzīvo ģimenē)...

Y Kuşağı Turistlerin Destinasyon İmaj Algıları Üzerine Bir Araştırma A Research On Generation Y Tourists Perceptions Of Destination Image

Directory of Open Access Journals (Sweden)

Aslı ALBAYRAK

2013-07-01

şağı turistlerin tatil yerlerine karar vermeleri üzerine destinasyon imajını oluşturan faktörlerin etkisini saptamak ve Y kuşağı turistlerin yapısal özellikleri ile destinasyon algıları arasındaki ilişkiyi inceleyerek söz konusu kuşak için destinasyon pazarlamasına ilişkin önerilerde bulunmak amacıyla yapılmıştır.Çalışmada nicel araştırma yöntemlerinden anket tekniğinden yararlanılmış, İstanbul’da bu kuşağı temsil eden ve kota örnekleme yöntemiyle belirlenen 384 kişiyle yüz yüze anket çalışması yapılmıştır. Elde elde verilerin analizinde betimsel istatistik, t-testi ve Anova Analizi kullanılmıştır.Araştırmanın sonuçlarına göre destinasyon imajı katılımcıların cinsiyetlerine, eğitim durumlarına ayrıca gelir düzeylerine göre farklılık göstermektedir. Diğer yandan, Y Kuşağı turistlerinin dinlenme, eğlenme ve yeni yerler görme isteği ile hareket ettikleri, kalite ve lüks bir tatili uygun fiyata arayan bireylerden oluştuğu söylenebilir.Turistik satın alma süreci birçok faktörün etkisiyle şekillenmektedir. Bu süreci etkileyen faktörlerden birisi de destinasyon imajıdır. En genel tanımıyla destinasyon imajı bireylerin bir yer hakkındaki genel algılarıdır ve bu algılar yaş, eğitim, gelir, kültür gibi bir çok faktörden etkilenmektedir. Geçmişte turistlerin destinasyon tercihleri ile ilgili çeşitli çalışmalar yapılmış ve bu çalışmalarda genel olarak turistlerin yaş, eğitim, kültür, gelir gibi özelliklerinin destinasyon imaj algıları üzerine etkileri incelenmiştir ancak farklı kuşakların destinasyon imaj algıları ile ilgili herhangi bir çalışmaya rastlanmamıştır. Bu nedenle bu çalışma sonucunda elde edilen sonuçların turizm pazarlamacılarına katkı sağlayabileceği düşünülmüştür.

Alternative end-joining catalyzes robust IgH locus deletions and translocations in the combined absence of ligase 4 and Ku70.

Science.gov (United States)

Boboila, Cristian; Jankovic, Mila; Yan, Catherine T; Wang, Jing H; Wesemann, Duane R; Zhang, Tingting; Fazeli, Alex; Feldman, Lauren; Nussenzweig, Andre; Nussenzweig, Michel; Alt, Frederick W

2010-02-16

Class switch recombination (CSR) in B lymphocytes is initiated by introduction of multiple DNA double-strand breaks (DSBs) into switch (S) regions that flank immunoglobulin heavy chain (IgH) constant region exons. CSR is completed by joining a DSB in the donor S mu to a DSB in a downstream acceptor S region (e.g., S gamma1) by end-joining. In normal cells, many CSR junctions are mediated by classical nonhomologous end-joining (C-NHEJ), which employs the Ku70/80 complex for DSB recognition and XRCC4/DNA ligase 4 for ligation. Alternative end-joining (A-EJ) mediates CSR, at reduced levels, in the absence of C-NHEJ, even in combined absence of Ku70 and ligase 4, demonstrating an A-EJ pathway totally distinct from C-NHEJ. Multiple DSBs are introduced into S mu during CSR, with some being rejoined or joined to each other to generate internal switch deletions (ISDs). In addition, S-region DSBs can be joined to other chromosomes to generate translocations, the level of which is increased by absence of a single C-NHEJ component (e.g., XRCC4). We asked whether ISD and S-region translocations occur in the complete absence of C-NHEJ (e.g., in Ku70/ligase 4 double-deficient B cells). We found, unexpectedly, that B-cell activation for CSR generates substantial ISD in both S mu and S gamma1 and that ISD in both is greatly increased by the absence of C-NHEJ. IgH chromosomal translocations to the c-myc oncogene also are augmented in the combined absence of Ku70 and ligase 4. We discuss the implications of these findings for A-EJ in normal and abnormal DSB repair.

Comparison of neutron and gamma irradiation effects on KU1 fused silica monitored by electron paramagnetic resonance

Energy Technology Data Exchange (ETDEWEB)

Bravo, D. [Department Fisica de Materiales, Universidad Autonoma de Madrid, E-28049 Madrid (Spain)], E-mail: david.bravo@uam.es; Lagomacini, J.C. [Department Fisica de Materiales, Universidad Autonoma de Madrid, E-28049 Madrid (Spain); Leon, M.; Martin, P. [Materiales para Fusion, CIEMAT, Avda. Complutense 22, E-28040 Madrid (Spain); Martin, A. [Department Fisica e Instalaciones, ETS Arquitectura UPM, E-28040 Madrid (Spain); Lopez, F.J. [Department Fisica de Materiales, Universidad Autonoma de Madrid, E-28049 Madrid (Spain); Ibarra, A. [Materiales para Fusion, CIEMAT, Avda. Complutense 22, E-28040 Madrid (Spain)

2009-06-15

Electron paramagnetic resonance (EPR) studies have been carried out on KU1 fused silica irradiated with neutrons at fluences 10{sup 21} and 10{sup 22} n/m{sup 2}, and gamma-ray doses up to 12 MGy. The effects of post-irradiation thermal annealing treatments, up to 850 deg. C, have also been investigated. Paramagnetic oxygen-related defects (POR and NBOHC) and E'-type defects have been identified and their concentration has been measured as a function of neutron fluence, gamma dose and post-irradiation annealing temperature. It is found that neutrons at the highest fluence generate a much higher concentration of defects (mainly E' and POR, both at concentrations about 5 x 10{sup 18} spins/cm{sup 3}) than gamma irradiations at the highest dose (mainly E' at a concentration about 4 x 10{sup 17} spins/cm{sup 3}). Moreover, for gamma-irradiated samples a lower treatment temperature (about 400 deg. C) is required to annihilate most of the observed defects than for neutron-irradiated ones (about 600 deg. C)

Radiosynthesis of [18F]fluorophenyl-L-amino acids by isotopic exchange on carbonyl-activated precursors

International Nuclear Information System (INIS)

Castillo Melean, Johnny

2011-01-01

Aromatic [ 18 F]fluoroamino acids have earlier been developed as promising probes for diagnostics using PET. However, a wider use of these radiofluorinated compounds has been limited due to radiosynthetic constraints. The work here presents an amenable three-step radiosynthesis pathway for the preparation of 2-[ 18 F]fluoro-L-phenylalanine (2-[ 18 F]Fphe), 2-[ 18 F]fluoro-L-tyrosine (2-[ 18 F]Ftyr), 6-[ 18 F]fuoro-L-m-tyrosine (6-[ 18 F]Fmtyr) and 6-[ 18 F]fluoro-L-DOPA (6-[ 18 F]FDOPA). For this, corresponding precursors were 18 F-fluorinated by nucleophilic isotopic exchange, followed by either removal of an activating formyl group with Rh(PPh 3 ) 3 Cl or its conversion by Baeyer-Villiger oxidation, respectively, and subsequent hydrolysis of protecting groups in acidic medium. Two efficient synthetic approaches were developed for the preparation of highly functionalized fluoro-benzaldehydes and -ketones which were used as labeling precursors. The compounds (2S,5S)-tert-butyl 2-tert-butyl-5-(2-fluoro-5-formylbenzyl)-3-methyl-4-oxoimidazolidine-1 -carboxylate (1a), (2S,5S)-tert-butyl 5-(5-acetyl-2-fluorobenzyl)-2-tert-butyl-3-methyl-4-oxoimidazolidine-1 -carboxylate (1c), (2S,5S)-benzyl 2-tert-butyl-5-(2-fluoro-5-formylbenzyl)-3-methyl-4-oxoimidazolidine-1 -carbo-xylate (1d), 4-fluoro-3-(((2S,5R)-5-isopropyl-3,6-dimethoxy-2,5-dihydropyrazin-2-yl) me-thyl)b enzal-dehyde (1e) and 1-(4-fluoro-3-(((2S,5R)-5-isopropyl-3,6-dimethoxy-2,5-dihydropyrazin-2-yl) me-thy l)phenyl)ethanone (1f), could be prepared in six steps and overall yields of 41%, 48%, 37%, 27%, and 32%, respectively. (2S,5S)-tert-Butyl 5-(4-(benzyloxy)-2-fluoro-5-formylbenzyl)-2-tert-butyl-3-methyl-4 -oxoimidazolidi ne-1-carboxylate (1b) was prepared in ten steps with an overall yield of 19% while compounds (2S,5S)-tert-butyl 5-(5-(3,5-bis(trifluoromethyl)-benzoyl)-2-fluorobenzyl)-2-tert-butyl-3 -methyl-4-oxoimidazolidine-1-carboxylate (1g) and (2S,5S)-tert-butyl 2-tert-butyl-5-(2-fluoro-5

Radiolabelling of isopeptide N epsilon-(gamma-glutamyl)-L-lysine by conjugation with N-succinimidyl-4-[18F]fluorobenzoate.

Science.gov (United States)

Wüst, F; Hultsch, C; Bergmann, R; Johannsen, B; Henle, T

2003-07-01

The isopeptide N(epsilon)-(gamma-glutamyl)-L-lysine 4 was labelled with 18F via N-succinimidyl-4-[18F]fluorobenzoate ([18F]SFB). A modified approach for the convenient synthesis of [18F]SFB was used, and [18F]SFB could be obtained in decay-corrected radiochemical yields of 44-53% (n = 20) and radiochemical purity >95% within 40 min after EOB. For labelling N(epsilon)-(gamma-glutamyl)-L-lysine with [18F]SFB the effects of isopeptide concentration, temperature, and pH were studied to determine the optimum reaction conditions. The coupling reaction was shown to be temperature and pH independent while being strongly affected by the isopeptide concentration. Using the optimized labelling conditions, in a typical experiment 1.3GBq of [18F]SFB could be converted into 447MBq (46%, decay-corrected) of [18F]fluorobenzoylated isopeptide within 45 min, including HPLC purification.

Coordination Compounds of Co Ni , Cu , Zn , Cd and Hg with ...

African Journals Online (AJOL)

CLEMENT O BEWAJI

Bipin B. Mahapatra* and Saroj Ku. Panda. **. **P.G. Department of Chemistry, G.M. (Autonomous) College, Sambalpur – 768004 (Orissa). India. Telephone ..... Ferraro, J.R: Low Frequency Vibration of Inorganic and Co-ordination Compound Plenum press, New York. USA: (1971). 10. Sacconi. L: J. Inorg. Nucl. Chem., 18 ...

A wideband superconducting filter at Ku-band based on interdigital coupling

Science.gov (United States)

Jiang, Ying; Wei, Bin; Cao, Bisong; Li, Qirong; Guo, Xubo; Jiang, Linan; Song, Xiaoke; Wang, Xiang

2018-04-01

In this paper, an interdigital-type resonator with strong electric coupling is proposed for the wideband high-frequency (>10 GHz) filter design. The proposed microstrip resonator consists of an H-shaped main line part with its both ends installed with interdigital finger parts. Strong electric coupling is achieved between adjacent resonators. A six-pole high-temperature superconducting filter at Ku-band using this resonator is designed and fabricated. The filter has a center frequency of 15.11 GHz with a fractional bandwidth of 30%. The insertion loss of the passband is less than 0.3 dB, and the return loss is greater than 14 dB without any tuning.

A creative approach to the development of an agenda for knowledge utilization: outputs from the 11th international knowledge utilization colloquium (KU 11).

Science.gov (United States)

Wilkinson, Joyce E; Rycroft-Malone, Jo; Davies, Huw T O; McCormack, Brendan

2012-12-01

A group of researchers and practitioners interested in advancing knowledge utilization met as a colloquium in Belfast (KU 11) and used a "world café" approach to exploit the social capital and shared understanding built up over previous events to consider the research and practice agenda. We considered three key areas of relevance to knowledge use: (1) understanding the nature of research use, influence and impact; (2) blended and collaborative approaches to knowledge production and use; and (3) supporting sustainability and spread of evidence-informed innovations. The approach enabled the development of artifacts that reflected the three areas and these were analyzed using a creative hermeneutic approach. The themes that emerged and which are outlined in this commentary are not mutually exclusive. There was much overlap in the discussions and therefore of the themes, reflecting the complex nature of knowledge translation work. The agenda that has emerged from KU 11 also reflects the participatory and creative approach in which the meeting was structured and focused, and therefore emphasizes the processual, relational and contingent nature of some of the challenges we face. The past 20 years has seen an explosion in activity around understanding KU, and we have learned much about the difficulties. Whilst the agenda for the next decade may be becoming clearer, colloquia such as KU 11, using creative and engaging approaches, have a key role to play in dissecting, articulating and sharing that agenda. In this way, we also build an ever-expanding international community that is dedicated to working towards increasing the chances of success for better patient care. © 2012 Sigma Theta Tau International.

Wpływ wysiłku fizycznego na funkcję układu oddechowego w twardzinie układowej

Directory of Open Access Journals (Sweden)

Stanisław Sierakowski

2010-12-01

Full Text Available Cel: Powikłania ze strony układu oddechowego stanowią główną przyczynę zgonów pacjentów z twardziną układową (TU. Tętniczenadciśnienie płucne i śródmiąższowa choroba płuc stanowią najistotniejszez nich. Pacjenci są jednak często zdiagnozowani dopierow późnym okresie choroby, dlatego też istotne jest opracowaniemetody diagnostycznej do wczesnego wykrywania tych powikłań.Celem pracy była ocena wpływu wysiłku fizycznego na zmiany parametrówoddechowych. Materiały i metody: Badania przeprowadzono wśród 32 pacjentów zezdiagnozowaną TU; 72% pacjentów miało postać ograniczoną TU,28% postać uogólnioną. Wykonywano pomiar zdolności dyfuzyjnejpłuc dla tlenku węgla (DLCO, natężonej pojemności życiowej (FVC,natężonej objętości wydechowej pierwszosekundowej (FEV1 orazcałkowitej pojemności płuc (TLC w spoczynku oraz bezpośrednio pozakończeniu wysiłku fizycznego. Wyniki: Pod wpływem wysiłku fizycznego obserwowano wzrostDLCO od 59,7% do 68,1% wartości należnej (p < 0,005. Nie stwierdzononatomiast istotnych statystycznie zmian wartości FVC, FEV1oraz TLC. Wnioski: U chorych na TU zdolność dyfuzyjna płuc dla tlenku węglapo wysiłku fizycznym uległa istotnej statystycznie poprawiew porównaniu z wartościami spoczynkowymi. Związane jest toz koniecznością zapewnienia właściwego utlenowania krwi tętniczeji wynika m.in. ze zwiększenia pojemności łożyska naczyniowego.W klinicznej interpretacji wartości DLCO należy uwzględniać opróczstężenia hemoglobiny i objętości pęcherzykowej także wpływ wysiłkuoraz związane z nim zmiany wielkości objętości rzutu serca.

Cooley anemia

International Nuclear Information System (INIS)

Ambrosino, M.; Rumancik, W.M.; Hernanz-Schulman, M.; Sanger, J.J.; Rey, M.; Rutkowski, M.; Genieser, N.B.

1988-01-01

Twelve children aged 7-24 years (mean 16 years; six boys, six girls) with homozygous thalassemia major and transfusional hemochromatosis were studied with MR imaging and thallium scintigraphy to determine if MR imaging could be used to detect regional myocrdial abnormalities identified on scintigrams. Resting myocardial perfusion images were obtained on a large field of view gamma camera after intravenous administration of Tl-201 chloride. Reginal myocardial walls were graded on the thallium images on a scale of 0-3, with higher grades indicating poorer thallium uptake. Cardiac MR imaging was performed on a 0.5-T system with every-beat electrocardiogram gating to acquire T1-weighted images. Signal intensity (SI) values were obtained from regional myocardial walls to match thallium regions and standardized as a ratio to the SI of adjacent fat. The authors found the mean standardized MR imaging SI values to decrease as correlated with increasing thallium grade abnormalities. Although analysis of variance of the mean regional SI values as classified by associated thallium grade showed only a 39% probability of significant difference between each grade, they found a 74% probability of significant difference between normal and abnormal regions

Improved foilless Ku-band transit-time oscillator for generating gigawatt level microwave with low guiding magnetic field

Energy Technology Data Exchange (ETDEWEB)

Ling, Junpu; He, Juntao, E-mail: hejuntao12@163.com; Zhang, Jiande; Jiang, Tao; Hu, Yi [College of Optoelectronic Science and Engineering, National University of Defense Technology, Changsha 410073 (China)

2014-09-15

An improved foilless Ku-band transit-time oscillator with low guiding magnetic field is proposed and investigated in this paper. With a non-uniform buncher and a coaxial TM{sub 02} mode dual-resonant reflector, this improved device can output gigawatt level Ku-band microwave with relatively compact radial dimensions. Besides the above virtue, this novel reflector also has the merits of high TEM reflectance, being more suitable for pre-modulating the electron beam and enhancing the conversion efficiency. Moreover, in order to further increase the conversion efficiency and lower the power saturation time, a depth-tunable coaxial collector and a resonant cavity located before the extractor are employed in our device. Main structure parameters of the device are optimized by particle in cell simulations. The typical simulation result is that, with a 380 kV, 8.2 kA beam guided by a magnetic field of about 0.6 T, 1.15 GW microwave pulse at 14.25 GHz is generated, yielding a conversion efficiency of about 37%.

Radiosynthesis and biological evaluation of N-(2-[18F]fluoropropionyl)-3,4-dihydroxy-l-phenylalanine as a PET tracer for oncologic imaging.

Science.gov (United States)

Tang, Caihua; Nie, Dahong; Tang, Ganghua; Gao, Siyuan; Liu, Shaoyu; Wen, Fuhua; Tang, Xiaolan

2017-07-01

Several 11 C and 18 F labeled 3,4-dihydroxy-l-phenylalanine (l-DOPA) analogues have been used for neurologic and oncologic diseases, especially for brain tumors and neuroendocrine tumors PET imaging. However, 18 F-labeled N-substituted l-DOPA analogues have not been reported so far. In the current study, radiosynthesis and biological evaluation of a new 18 F-labeled l-DOPA analogue, N-(2-[ 18 F]fluoropropionyl)-3,4-dihydroxy-l-phenylalanine ([ 18 F]FPDOPA) for tumor PET imaging are performed. The synthesis of [ 18 F]FPDOPA was via a two-step reaction sequence from 4-nitrophenyl-2-[ 18 F]fluoropropionate ([ 18 F]NFP). The biodistribution of [ 18 F]FPDOPA was determined in normal Kunming mice. In vitro competitive inhibition and protein incorporation experiments were performed with SPC-A-1 lung adenocarcinoma cell lines. PET/CT studies of [ 18 F]FPDOPA were conducted in C6 rat glioma and SPC-A-1 human lung adenocarcinoma and H460 human large cell lung cancer-bearing nude mice. [ 18 F]FPDOPA was prepared with a decay-corrected radiochemical yield of 28±5% and a specific activity of 50±15GBq/μmol (n=10) within 125min. In vitro cell experiments showed that [ 18 F]FPDOPA uptake in SPC-A-1 cells was primarily transported through Na + -independent system L, with Na + -dependent system B 0,+ and system ASC partly involved in it. Biodistribution data in mice showed that renal-bladder route was the main excretory system of [ 18 F]FPDOPA. PET imaging demonstrated intense accumulation of [ 18 F]FPDOPA in several tumor xenografts, with (8.50±0.40)%ID/g in C6 glioma, (6.30±0.12)%ID/g in SPC-A-1 lung adenocarcinoma, and (6.50±0.10)%ID/g in H460 large cell lung cancer, respectively. A novel N-substituted 18 F-labeled L-DOPA analogue [ 18 F]FPDOPA is synthesized and evaluated in vitro and in vivo. The results support that [ 18 F]FPDOPA seems to be a potential PET tracer for tumor imaging, especially be a better potential PET tracer than [ 18 F]fluoro-2-deoxy-d-glucose ([ 18 F

A chimeric 18L1-45RG1 virus-like particle vaccine cross-protects against oncogenic alpha-7 human papillomavirus types.

Directory of Open Access Journals (Sweden)

Bettina Huber

Full Text Available Persistent infection with oncogenic human papillomaviruses (HPV types causes all cervical and a subset of other anogenital and oropharyngeal carcinomas. Four high-risk (hr mucosal types HPV16, 18, 45, or 59 cause almost all cervical adenocarcinomas (AC, a subset of cervical cancer (CxC. Although the incidence of cervical squamous cell carcinoma (SCC has dramatically decreased following introduction of Papanicolaou (PAP screening, the proportion of AC has relatively increased. Cervical SCC arise mainly from the ectocervix, whereas AC originate primarily from the endocervical canal, which is less accessible to obtain viable PAP smears. Licensed (bivalent and quadrivalent HPV vaccines comprise virus-like particles (VLP of the most important hr HPV16 and 18, self-assembled from the major capsid protein L1. Due to mainly type-restricted efficacy, both vaccines do not target 13 additional hr mucosal types causing 30% of CxC. The papillomavirus genus alpha species 7 (α7 includes a group of hr types of which HPV18, 45, 59 are proportionally overrepresented in cervical AC and only partially (HPV18 targeted by current vaccines. To target these types, we generated a chimeric vaccine antigen that consists of a cross-neutralizing epitope (homologue of HPV16 RG1 of the L2 minor capsid protein of HPV45 genetically inserted into a surface loop of HPV18 L1 VLP (18L1-45RG1. Vaccination of NZW rabbits with 18L1-45RG1 VLP plus alum-MPL adjuvant induced high-titer neutralizing antibodies against homologous HPV18, that cross-neutralized non-cognate hr α7 types HPV39, 45, 68, but not HPV59, and low risk HPV70 in vitro, and induced a robust L1-specific cellular immune response. Passive immunization protected mice against experimental vaginal challenge with pseudovirions of HPV18, 39, 45 and 68, but not HPV59 or the distantly related α9 type HPV16. 18L1-45RG1 VLP might be combined with our previously described 16L1-16RG1 VLP to develop a second generation bivalent

A single one-step radiosynthesis of [{sup 18}F]L.B.T.-999, a novel and selective dat radioligand for PET

Energy Technology Data Exchange (ETDEWEB)

Dolle, F.; Hinnen, F.; Saba, W.; Schollhorn-peyronneau, M.A.; Valette, H.; Bottlaender, M. [Service Hospitalier Frederic Joliot, DSV/ Institut d' Imagerie BioMedicale, 91 - Orsay (France); Helfenbein, J.; Le gailliard, J. [Institut National de la Sante et de la Recherche Medicale (INSERM), U484, Orphachem, ZATE, 63 - Clermont Ferrand (France); Mavel, S.; Mincheva, Z.; Garreau, L.; Chalon, S.; Guilloteau, D.; Emond, P. [Institut National de la Sante et de la Recherche Medicale (INSERM), U619, 37 - Tours (France); Mavel, S.; Garreau, L.; Chalon, S.; Guilloteau, D.; Emond, P. [Universite Francois Rabelais de Tours, 37 (France); Halldin, C. [Karolinska Institut, Dept. of Clinical Neuroscience, Karolinska Hospital, Stockholm (Sweden); Madelmont, J.C. [Institut National de la Sante et de la Recherche Medicale (INSERM) U484, Lab. Etude Metabolique des Molecules Marquees, 63 - Clermont Ferrand (France); Deloye, J.B. [Biopole Clermont Limagne, Lab. Cyclopharma, 63 - Saint Beauzire (France); Guilloteau, D. [Centre Hospitalier Regional Universitaire, 37 - Tours (France)

2008-02-15

L.B.T.-999 (8-((E)-4-fluoro-but-2-enyl)-3-beta-p-tolyl-8- aza-bi-cyclo[3.2.1]octane-2-beta-carboxylic acid methyl ester) is a recently developed cocaine derivative belonging to a new generation of highly selective D.A.T. ligands [1-3]. Initial fluorine-18-labelling of L.B.T.-999 was based on the robust and reliable two-step radiochemical pathway often reported for such tropane derivatives, involving first the preparation of (E)-1-[{sup 18}F]fluoro-4-tosyloxybut-2-ene followed by a N-alkylation reaction with the appropriate nor-tropane moiety [4]. In the present work, a simple one-step fluorine-18-labelling of L.B.T.-999 is reported, based on a chlorine-for-fluorine nucleophilic aliphatic substitution, facilitating as expected both automation and final H.P.L.C. purification. The process involves: (A) reaction of K[{sup 18}F]F-Kryptofix 222 with the chlorinated precursor (3.5-4.5 mg) at 165 degrees C for 10 min in D.M.S.O. (0.6 m L) followed by (B) C-18 PrepSep cartridge pre-purification and finally (C) semi preparative HPLC purification on a Waters Symmetry C-18. Typically, 3.70-5.92 GBq of [{sup 18}F]L.B.T.-999 (> 95% chemically and radiochemically pure) could be obtained with specific radioactivities ranging from 37 to 111 GBq/micro-mol within 85-90 min (HPLC purification and Sep-Pak-based formulation included), starting from a 37.0 GBq [{sup 18}F]fluoride batch (overall radiochemical yields: 10-16%, non decay corrected) [5].Supported in part by the E.C. - F.P.6-project D.i.M.I. (L.S.H.B.-C.T.- 2005-512146) and the R.N.T.S. 03 B 243 Fluoropak program. (authors)

Rapid Recruitment of BRCA1 to DNA Double-Strand Breaks Is Dependent on Its Association with Ku80▿ †

Science.gov (United States)

Wei, Leizhen; Lan, Li; Hong, Zehui; Yasui, Akira; Ishioka, Chikashi; Chiba, Natsuko

2008-01-01

BRCA1 is the first susceptibility gene to be linked to breast and ovarian cancers. Although mounting evidence has indicated that BRCA1 participates in DNA double-strand break (DSB) repair pathways, its precise mechanism is still unclear. Here, we analyzed the in situ response of BRCA1 at DSBs produced by laser microirradiation. The amino (N)- and carboxyl (C)-terminal fragments of BRCA1 accumulated independently at DSBs with distinct kinetics. The N-terminal BRCA1 fragment accumulated immediately after laser irradiation at DSBs and dissociated rapidly. In contrast, the C-terminal fragment of BRCA1 accumulated more slowly at DSBs but remained at the sites. Interestingly, rapid accumulation of the BRCA1 N terminus, but not the C terminus, at DSBs depended on Ku80, which functions in the nonhomologous end-joining (NHEJ) pathway, independently of BARD1, which binds to the N terminus of BRCA1. Two small regions in the N terminus of BRCA1 independently accumulated at DSBs and interacted with Ku80. Missense mutations found within the N terminus of BRCA1 in cancers significantly changed the kinetics of its accumulation at DSBs. A P142H mutant failed to associate with Ku80 and restore resistance to irradiation in BRCA1-deficient cells. These might provide a molecular basis of the involvement of BRCA1 in the NHEJ pathway of the DSB repair process. PMID:18936166

Izrada 3D modela kućišta ravnog ventila DN 50

OpenAIRE

Hršak, Božidar; Golubić, Stjepan; Bošnjak, Matej

2012-01-01

Prikazana je izrada 3D modela kućišta centrifugalne pumpe na temelju postojećeg 2D nacrta gotovog proizvoda primjenom sinkrone tehnologije 3D modeliranja, i reverzibilnog inženjeringa. Na temelju kreiranog 3D modela, predložene su moguće modifikacije postojeće izvedbe proizvoda. Provedene su analize zakrivljenosti površina, Bézierove krivulje modela i 3D geometrije. Prikazana je i mogućnost vizualizacije gotovog 3D modela na Web stranicama u cilju prezentiranja proizvoda budućim kupcima primj...

Shuttle Ku-band bent-pipe implementation considerations. [for Space Shuttle digital communication systems

Science.gov (United States)

Batson, B. H.; Seyl, J. W.; Huth, G. K.

1977-01-01

This paper describes an approach for relay of data-modulated subcarriers from Shuttle payloads through the Shuttle Ku-band communications subsystem (and subsequently through a tracking and data relay satellite system to a ground terminal). The novelty is that a channel originally provided for baseband digital data is shown to be suitable for this purpose; the resulting transmission scheme is referred to as a narrowband bent-pipe scheme. Test results demonstrating the validity of the narrowband bent-pipe mode are presented, and limitations on system performance are described.

Detailed modeling of local anisotropy and transverse Ku interplay regarding hysteresis loop in FeCuNbSiB nanocrystalline ribbons

Science.gov (United States)

Geoffroy, Olivier; Boust, Nicolas; Chazal, Hervé; Flury, Sébastien; Roudet, James

2018-04-01

This article focuses on the modeling of the hysteresis loop featured by Fe-Cu-Nb-Si-B nanocrystalline alloys with transverse induced anisotropy. The magnetization reversal process of a magnetic correlated volume (CV), characterized by the induced anisotropy Ku, and a deviation of the local easy magnetization direction featuring the effect of a local incoherent anisotropy Ki, is analyzed, taking account of magnetostatic interactions. Solving the equations shows that considering a unique typical kind of CV does not enable accounting for both the domain pattern and the coercivity. Actually, the classical majority CVs obeying the random anisotropy model explains well the domain pattern but considering another kind of CVs, minority, mingled with classical ones, featuring a magnitude of Ki comparable to Ku, is necessary to account for coercivity. The model has been successfully compared with experimental data.

Radiosynthesis of 1-[{sup 18}F]fluoroethyl-L-tryptophan as a novel potential amino acid PET tracer

Energy Technology Data Exchange (ETDEWEB)

Sun Ting, E-mail: beibeisun2008@163.com [Department of Cardiac Function, Shanghai Ninth People' s Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, Shanghai 200011 (China); Tang Ganghua, E-mail: gtang0224@yahoo.com.cn [Department of Nuclear Medicine, the first affiliated hospital, SunYat-Sen University, Guangzhou 510080 (China); Tian Hua [State Key Laboratory of Oncogenes and Related Genes, Shanghai Cancer Institute, Renji Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200032 (China); Wang Xiaoyan [Department of Nuclear Medicine, the first affiliated hospital, SunYat-Sen University, Guangzhou 510080 (China); Chen Xianghua [Department of Cardiac Function, Shanghai Ninth People' s Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, Shanghai 200011 (China); Chen Zhifeng [Department of Nuclear Medicine, the first affiliated hospital, SunYat-Sen University, Guangzhou 510080 (China); Wang Shihchen [Department of Nuclear Medicine, Peking Union Medical College and Chinese Academy of Medical Sciences, Peking Union Medical College Hospital, 1 Shuaifuyuan Wangfujing Beijing 100730 (China)

2012-04-15

{sup 18}F labeled natural amino acids have been introduced as promising tumor imaging agents. A novel [{sup 18}F]fluoro amino acid analog 1-[{sup 18}F]fluoroethyl-L-tryptophan (1-[{sup 18}F]FETrp) was designed and synthesized by a two-pot three-step procedure, including the synthesis of 1-[{sup 18}F]fluoro-2- (tosyloxy)ethane, the [{sup 18}F]fluoroethylation of the precursor N-Boc-L-tryptophan ethyl ester and following the deprotection of the tert-butoxycarbonyl and ethyl ester protecting groups. 1-[{sup 18}F]FETrp was resulted in 0.9{+-}0.2% (n=5) radiochemical yields (no decay corrected) by HPLC purification, within a total synthesis time of 65 min. The radiochemical purity of 1-[{sup 18}F]FETrp was 95-97%. The radiosynthetic method needs to be further optimized to get a satisfying radiochemical yield. - Highlights: Black-Right-Pointing-Pointer We designed and synthesized the novel amino acid analog 1-[{sup 19}F]FETrp. Black-Right-Pointing-Pointer We radiosynthesized 1-[{sup 18}F]FETrp using the two-pot three-step procedure. Black-Right-Pointing-Pointer The total synthesis time was 65 min and the yield was very low. Black-Right-Pointing-Pointer The synthetic strategy via [{sup 18}F]FCH{sub 2}CH{sub 2}OTs needs to be optimized or changed.

[{sup 18}F]L.B.T.-999, a new radioligand to study the dopamine transporter with PET: characterization in baboons

Energy Technology Data Exchange (ETDEWEB)

Saba, W.; Schollhorn, M.A.; Valette, H.; Dolle, F.; Bottlaender, M. [Service Hospitalier Frederic Joliot, DRM/DSV, 91 - Orsay (France); Chalon, S.; Garreau, L.; Emond, P.; Guilloteau, D. [Institut National de la Sante et de la Recherche Medicale (INSERM), U619, 37 - Tours (France); Deloye, J.B. [Cyclopharma, 63 - Clermont Ferrand (France)

2008-02-15

The dopamine transporter (D.A.T.) is the main regulator of the synaptic concentration of dopamine in the brain and plays a key role in many neurological and psychiatric diseases. The goal of the study was to characterize the properties of [{sup 18}F]L.B.T.-999 in baboons. Regional brain distribution was examined in vitro by autoradiographic studies on brain sections and in vivo by PET. Results of in vitro autoradiographic studies were in agreement with the localisation of the D.A.T. and revealed high level of [{sup 18}F]L.B.T.-999 binding in the putamen and caudate, moderate level in the midbrain, and low level in the cortex and cerebellum. In PET study, the time course of the concentration of [{sup 18}F]L.B.T.-999 in different regions of the brain showed that the highest accumulation of [{sup 18}F]L.B.T.-999 was observed in the striatum with a peak uptake at 50 min (maximum = 5.7 {+-} 1.7 and 4.7 {+-}1.0% I.D./100 ml in putamen and caudate nucleus respectively, n 5). The radioactivity uptake peaked at 8 min in the midbrain (2.3 {+-} 1.2% I.D./100 ml) and decreased rapidly as a function of time. The lowest uptake was observed in the cortex (0.62 {+-}0.1 % I.D./100 ml, at 50 min) and in the cerebellum (0.44 {+-} 0.08% I.D./100 ml, at 50 min). In the test retest studies (n = 3) the variability of the uptake was 5% in the putamen and 6% in the caudate. Following HPLC analysis of plasma samples, [{sup 18}F]L.B.T.-999 was rapidly metabolized. Unchanged [{sup 18}F]L.B.T.-999 accounted for around 21% and 7% of the radioactivity at 30 and 120 min post-injection respectively. The region to cerebellum radioactivity ratio was calculated. This ratio reached a maximum at 110 min post injection (22.1 {+-} 4.6 and 18.8 {+-} 2.1 in the putamen and the caudate respectively) and remained stable during the time of the PET scan (4 h). This ratio was 4.21 {+-} 0.92, 2.0 {+-} 0.3 and 1.6 {+-} 0.2 in the midbrain, thalamus, and cortical structure at 110 min post-injection. Binding

A ribonuclease-resistant region of 5S RNA and its relation to the RNA binding sites of proteins L18 and L25

DEFF Research Database (Denmark)

Douthwaite, S; Garrett, R A; Wagner, R

1979-01-01

An RNA fragment, constituting three subfragments of nucleotide sequences 1-11, 69-87 and 89-120, is the most ribonuclease-resistant part of the native 5S RNA of Escherichia coli, at 0 degrees C. A smaller fragment of nucleotide sequence 69-87 and 90-110 is ribonuclease-resistant at 25 degrees....... Degradation of the L25-5S RNA complex with ribonuclease A or T2 yielded RNA fragments similar to those of the free 5S RNA at 0 degrees C and 25 degrees C; moreover L25 remained strongly bound to both RNA fragments and also produced some opening of the RNA structure in at least two positions. Protein L18...... initially protected most of the 5S RNA against ribonuclease digestion, at 0 degrees C, but was then gradually released prior to the formation of the larger RNA fragment. It cannot be concluded, therefore, as it was earlier (Gray et al., 1973), that this RNA fragment contains the primary binding site of L18....

Effects of 18 months of L-T4 replacement in women with subclinical hypothyroidism.

LENUS (Irish Health Repository)

Adrees, M

2012-02-01

CONTEXT: Some of the cardiovascular and renal abnormalities seen in overt hypothyroidism have also been reported in subclinical hypothyroidism (SCH). Short-term L-T4 replacement in SCH improves cardiovascular risk markers and reduces carotid intima-media thickness (CIMT), a surrogate marker of atherosclerosis. The haemodynamic and renal effects of L-T4 replacement in SCH are poorly understood. OBJECTIVES: To compare cardiovascular risk factors and renal variables in women with SCH and normal women. To study the effects of L-T4 replacement in SCH subjects on these variables and on structural and functional changes in common carotid and brachial arteries. DESIGN: Fifty-six women with SCH before and after L-T4 replacement for 18 months and 56 normal women of similar age distribution were studied. Blood Pressure (BP), plasma lipids and homocysteine were measured and renal function evaluated [estimation of glomerular filtration rate (eGFR) using standard equations and measurement of serum Cystatin-C] in women with SCH before and after 18 months of l-T4, and in healthy women. CIMT and endothelial function (using brachial artery ultrasound) were studied before and after L-T4 in a subgroup of women with SCH. RESULTS: Systolic and diastolic BP, total cholesterol, triglyceride, LDL-cholesterol, lipoprotein(a) and homocysteine were greater in SCH (P < 0.05), and following L-T4 replacement decreased (P < 0.05) to levels that no longer differed from normal subjects. Estimated GFR was reduced and serum Cystatin-C increased (P < 0.05) in SCH. These variables also normalized following L-T4. Following L-T4 replacement the carotid artery baseline diameter increased by 7.1% and CIMT decreased by a mean value of 13%, while brachial artery diameter increased basally by 12.5% and following endothelium-dependent vasodilatation by 17.5% (P < 0.05). However, the increment following reactive hyperaemia did not differ before or following L-T4 replacement. CONCLUSION: Normalization of

Hexagonal perovskites with cationic vacancies. 20. Ba/sub 6/Nb/sub 4/ZrvacantO/sub 18/ - a new stacking polytype with a rhombohedral 18 L structure

Energy Technology Data Exchange (ETDEWEB)

Schittenhelm, H J; Kemmler-Sack, S [Tuebingen Univ. (Germany, F.R.). Lehrstuhl fuer Anorganische Chemie 2

1980-06-01

The white Ba/sub 6/Nb/sub 4/ZrvacantO/sub 18/ crystallizes in a rhombohedral 18 L structure (a = 5.82/sub 1/ A; c = 42.6/sub 3/ A; space group R3m) with three formula units for the trigonal setting (rhosub(exp) = 6.0/sub 5/ g/cm/sup 3/; rhosub(calc) = 6.27/sub 1/ g/cm/sup 3/). The corresponding Tisup(IV) and Hfsup(IV) compounds, Ba/sub 6/Nb/sub 4/TivacantO/sub 18/ and Ba/sub 6/Nb/sub 4/HfvacantO/sub 18/, are isotypic.

Predominant contribution of L-type amino acid transporter to 4-borono-2-18F-fluoro-phenylalanine uptake in human glioblastoma cells

International Nuclear Information System (INIS)

Yoshimoto, Mitsuyoshi; Kurihara, Hiroaki; Honda, Natsuki; Kawai, Keiichi; Ohe, Kazuyo; Fujii, Hirofumi; Itami, Jun; Arai, Yasuaki

2013-01-01

Introduction: 4-Borono-2- 18 F-fluoro-phenylalanine ( 18 F-FBPA) has been used to anticipate the therapeutic effects of boron neutron capture therapy (BNCT) with 4-borono-L-phenylalanine (BPA). Similarly, L-[methyl- 11 C]-methionine ( 11 C-MET), the most popular amino acid PET tracer, is a possible candidate for this purpose. We investigated the transport mechanism of 18 F-FBPA and compared it with that of 14 C-MET in human glioblastoma cell lines. Methods: Uptake of 18 F-FBPA and 14 C-MET was examined in A172, T98G, and U-87MG cells using 2-aminobicyclo-(2.2.1)-heptane-2-carboxylic acid (a system L-specific substrate), 2-(methylamino)-isobutyric acid (a system A-specific substrate), and BPA. Gene expression was analyzed by quantitative real time polymerase chain reaction. Results: System L was mainly involved in the uptake of 18 F-FBPA (74.5%–81.1% of total uptake) and 14 C-MET (48.3%–59.4%). System A and ASC also contributed to the uptake of 14 C-MET. Inhibition experiments revealed that BPA significantly decreased the uptake of 18 F-FBPA, whereas 31%–42% of total 14 C-MET uptake was transported by BPA non-sensitive transporters. In addition, 18 F-FBPA uptake correlated with LAT1 and total LAT expressions. Conclusion: This study demonstrated that 18 F-FBPA was predominantly transported by system L in human glioblastoma cells compared to 14 C-MET. Although further studies are needed to elucidate the correlation between 18 F-FBPA uptake and BPA content in tumor tissues, 18 F-FBPA is suitable for the selection of patients who benefit from BNCT with BPA

Analysis of Standards Efficiency in Digital Television Via Satellite at Ku and Ka Bands

Directory of Open Access Journals (Sweden)

Landeros-Ayala Salvador

2013-06-01

Full Text Available In this paper, an analysis on the main technical features of digital television standards for satellite transmission is carried out. Based on simulations and link budgets, the standard with the best operational performance is defined, based on simulations and link budget analysis, as well as a comparative efficiency analysis is conducted for the Ku and Ka bands for both transparent and regenerative transponders in terms of power, bandwidth, information rate and link margin, including clear sky, uplink rain, downlink rain and rain in both.

Investigation on the performance of an optically generated RF local oscillator signal in Ku-band DVB-S systems

NARCIS (Netherlands)

Khan, M.R.H.; Marpaung, D.A.I.; Burla, M.; Roeloffzen, C.G.H.; Bernhardi, Edward; de Ridder, R.M.

2011-01-01

We investigate a way to externally generate the local oscillator (LO) signal used for downconversion of the Ku-band (10.7 − 12.75 GHz) RF signal received from a phased array antenna (PAA). The signal is then translated to an intermediate frequency (950 − 2150 MHz) at the output of the mixer of

The pretreatment of corn stover with Gloeophyllum trabeum KU-41 for enzymatic hydrolysis

Directory of Open Access Journals (Sweden)

Gao Ziqing

2012-05-01

Full Text Available Abstract Background Pretreatment is an essential step in the enzymatic hydrolysis of biomass for bio-ethanol production. The dominant concern in this step is how to decrease the high cost of pretreatment while achieving a high sugar yield. Fungal pretreatment of biomass was previously reported to be effective, with the advantage of having a low energy requirement and requiring no application of additional chemicals. In this work, Gloeophyllum trabeum KU-41 was chosen for corn stover pretreatment through screening with 40 strains of wood-rot fungi. The objective of the current work is to find out which characteristics of corn stover pretreated with G. trabeum KU-41 determine the pretreatment method to be successful and worthwhile to apply. This will be done by determining the lignin content, structural carbohydrate, cellulose crystallinity, initial adsorption capacity of cellulase and specific surface area of pretreated corn stover. Results The content of xylan in pretreated corn stover was decreased by 43% in comparison to the untreated corn stover. The initial cellulase adsorption capacity and the specific surface area of corn stover pretreated with G. trabeum were increased by 7.0- and 2.5-fold, respectively. Also there was little increase in the cellulose crystallinity of pretreated corn stover. Conclusion G. trabeum has an efficient degradation system, and the results indicated that the conversion of cellulose to glucose increases as the accessibility of cellulose increases due to the partial removal of xylan and the structure breakage of the cell wall. This pretreatment method can be further explored as an alternative to the thermochemical pretreatment method.

Study of the Effect of Simulated Rain on the Offset Parabolic Antenna at Ku-Band with Different Elevation Angles

Directory of Open Access Journals (Sweden)

H. Mostafa

2007-01-01

Full Text Available Effect of rain on the receiver antenna is a major factor to degrade the system performance in a frequency above 10 GHz. This paper deals with the wet antenna attenuation at Ku-band with three different frequencies at different rain rates. During the Ku-band propagation experiment, it was discovered that rain water on the antenna caused a significant attenuation. It is necessary to estimate the losses caused by water on the antenna in order to separate these losses from the atmospheric propagation losses. The experiment was done at USM Engineering Campus to study the attenuation for these physical parameters. A Ku-band RF signal was generated by a signal generator and transmitted via horn antenna. The signal was received using a smooth offset antenna of 60 cm by 54 cm (Astro dish and measured using spectrum analyzer. In order to simulate a rain, pipes with bores of a same distance were implemented. Three cases were considered: in the first case one pipe was used to simulate low rain rate, the second case two pipes were used to simulate medium rain rate, and the third case three pipes were used to simulate heavy rain rate. In addition, the tap was used to control the flow of water in order to get more values of rain rate. The total attenuation of RF signals due to water layer on the feed and on the reflector feed was found to be 3.1 dB at worst case. On the other hand, the attenuation of RF signal due to the feed only was 2.83 dB, so the major attenuation occur was due to feed.

New uranium chalcoantimonates, RbU{sub 2}SbS{sub 8} and KU{sub 2}SbSe{sub 8}, with a polar noncentrosymmetric structure

Energy Technology Data Exchange (ETDEWEB)

Choi, K S; Kanatzidis, M G

1999-09-01

The new compounds, RbU{sub 2}SbS{sub 8} and KU{sub 2}SbSe{sub 8}, were prepared as golden-black, blocklike crystals by the polychalcogenide molten flux method. RbU{sub 2}SbS{sub 8} has a two-dimensional character with layers running perpendicular to the c-axis. The coordination geometry around the U{sup 4+} atoms is best described as a bicapped trigonal prism. The trigonal prisms share triangular faces with neighboring prisms, forming one-dimensional columns along the a-axis. The columns are then joined to construct sheets by sharing capping S atoms. Sb{sup 3+} ions are sitting at the center of a slightly distorted seesaw coordination environment (CN = 4). Rb{sup +} ions are stabilized in 8-coordinate bicapped trigonal prismatic sites. KU{sub 2}SbSe{sub 8} has essentially the same structure as RbU{sub 2}SbS{sub 8}. However, Sb{sup 3+} and K{sup +} ions appear disordered in every other layer resulting in a different unit cell. RbU{sub 2}SbS{sub 8} is a semiconductor with a band gap of 1.38 eV. The band gap of KU{sub 2}SbSe{sub 8} could not be determined precisely due to the presence of overlapping intense f-f transitions in the region (0.5--1.1 eV). The Raman spectra show the disulfide stretching vibration in RbU{sub 2}SbS{sub 8} at 479 cm{sup {minus}1} and the diselenide stretching vibration in KU{sub 2}SbSe{sub 8} at 252 cm{sup {minus}1}. Magnetic susceptibility measurements indicate the presence of U{sup 4+} centers in the compounds. The compounds do not melt below 1,000 C under vacuum.

STS-79 Ku-band antenna, ODS and Spacehab module at PCR

Science.gov (United States)

1996-01-01

The orbiter Ku-band antenna looms large in this view of the Space Shuttle Atlantis' payload bay. Visible just past the antenna system -- stowed on the starboard side of the payload bay wall -- is the Orbiter Docking System (ODS), and connected to the ODS via a tunnel is the Spacehab Double Module in the aft area of the payload bay. This photograph was taken from the starboard wing platform on the fifth level of the Payload Changeout Room (PCR) at Launch Pad 39A. Work is under way in the PCR to close Atlantis' payload bay doors for flight. Atlantis currently is being targeted for liftoff on Mission STS-79, the fourth docking of the U.S. Shuttle to the Russian Space Station Mir, around September 12.

Analysis of Fade Dynamic at Ku-Band in Malaysia

Directory of Open Access Journals (Sweden)

Siat Ling Jong

2014-01-01

Full Text Available This work investigates fade dynamics of satellite communication systems in equatorial heavy rain region based on a one year of Ku-band propagation measurement campaign carried out in Universiti Teknologi Malaysia (UTM, Johor, Malaysia. First order statistics of rain attenuation are deduced and the results are found to be in good agreement with those obtained from other beacon measurements gathered within the same area (Kuala Lumpur. Moreover, the fade duration and slope statistics of the satellite signal variations are also carefully derived and subsequently compared with the ITU-R recommendation model. Such information is useful for the system operator and radio communication engineer for the design of appropriate fade mitigation techniques as well as the quality of service that could be offered to the user (according to the time interval for a typical day. Further evaluation on the performances of several ITU-R models in the heavy rain region are needed based on the measurement database available of this climatic region.

On the synthesis of radiofluorinated amino acids by isotope exchange based on the example of 6-[18F]Fluor-L-DOPA

International Nuclear Information System (INIS)

Wagner, F.M.

2008-06-01

In nuclear medical diagnosis, 6-[ 18 F]fluoro-L-3,4-dihydroxyphenylalanine (6-[ 18 F]fluoro-LDOPA), an analogue of L-DOPA, is one of the few established radiopharmaceuticals used for the in vivo investigation of the presynaptic dopaminergic metabolism and of some kind of tumours via Positron Emission Tomography (PET). The presently used method of preparation of the radiotracer by electrophilic labelling is limited to low amounts of activity at high costs. Known nucleophilic syntheses, however, result either in insufficient enantiomeric purity or the known multi-step syntheses are hard to automate, due to their complexity. During this work a novel, easy to automate alternative for the preparation of 6-[ 18 F]fluoro-L-DOPA, was developed and evaluated, using a direct nucleophilic 18 F-fluorination of a protected amino acid derivative. The resulting product has a very high enantiomeric purity. At first, the general suitability of the (S)-BOC-BMI-derivatives for the synthesis of 18 F-labelled amino acids, used in this work, was investigated using a less complex precursor, which resulted in the amino acid 6-[ 18 F]fluoro-L-m-tyrosin via acidic hydrolysis. The preparation of a useful precursor for the nucleophilic 18 F-isotope substitution, namely the (2S,5S)-tert.-butyl- 5-(2-fluoro-5-formylbenzyl)-2-tert. -butyl-3-methyl-4-oxoimidazolidine-1-carbox= yl ate, was investigated in three general different ways. At first it was tried to obtain this product via formylation after coupling with the BOC-BMI, secondly via α,β-dehydro amino acid derivatives and finally via a systematic multi-step synthesis. Only the last mentioned way resulted in a precursor with sufficient purity that could be labelled. The radiochemical yield of the isotopic exchange was about 60 %. In the next step, the presented concept was modified to synthesize a precursor for the preparation of 6-[ 18 F]fluoro-L-DOPA. Only a combination of the protecting groups benzyl and THP resulted in the useful

O-(2-[{sup 18}F]Fluorethyl)-L-tyrosine in the diagnostics of brain tumors; O-(2-[{sup 18}F]Fluorethyl)-L-Tyrosin (FET) in der Diagnostik von Hirntumoren

Energy Technology Data Exchange (ETDEWEB)

Langen, K.J.; Stoffels, G. [Forschungszentrum Juelich (Germany). Inst. fuer Neurowissenschaften und Biophysik - Medizin

2009-06-15

Positron emission tomography (PET) using radiolabeled amino acids has shown great potential for a more accurate diagnosis of cerebral gliomas. Magnetic resonance imaging (MRI) is the investigation of choice for diagnosing cerebral glioma, but its capacity to differentiate tumor tissue from non-specific tissue changes is limited. ([{sup 18}F] Fluorethyl)-L-tyrosine (FET) is a new tracer for PET that can be produced with high efficiency and distributed on a wide clinical scale like [{sup 18}F]-Fluorodeoxyglucose (FDG). The use of FET PET allows better delineation of tumor margins and improves targeting of biopsy and radiotherapy, and planning surgery. In addition, amino acid imaging appears useful in distinguishing tumor recurrence from non-specific post-therapeutic scar tissue, predicting prognosis in low grade gliomas, and monitoring metabolic response during treatment. (orig.)

55K isoform of CDK9 associates with Ku70 and is involved in DNA repair

International Nuclear Information System (INIS)

Liu, Hongbing; Herrmann, Christine H.; Chiang, Karen; Sung, Tzu-Ling; Moon, Sung-Hwan; Donehower, Lawrence A.; Rice, Andrew P.

2010-01-01

Positive elongation factor b (P-TEFb) is a cellular protein kinase that is required for RNA polymerase II (RNAP II) transcriptional elongation of protein coding genes. P-TEFb is a set of different molecular complexes, each containing CDK9 as the catalytic subunit. There are two isoforms of the CDK9 protein - the major 42 KDa CDK9 isoform and the minor 55KDa isoform that is translated from an in-frame mRNA that arises from an upstream transcriptional start site. We found that shRNA depletion of the 55K CDK9 protein in HeLa cells induces apoptosis and double-strand DNA breaks (DSBs). The levels of apoptosis and DSBs induced by the depletion were reduced by expression of a 55K CDK9 protein variant resistant to the shRNA, indicating that these phenotypes are the consequence of depletion of the 55K protein and not off-target effects. We also found that the 55K CDK9 protein, but not the 42K CDK9 protein, specifically associates with Ku70, a protein involved in DSB repair. Our findings suggest that the 55K CDK9 protein may function in repair of DNA through an association with Ku70.

Teeling Whiskey Company: A tradition of family entrepreneurship and whiskey distilling

OpenAIRE

O'Gorman, Colm; Brophy, Martina; Clinton, Eric

2015-01-01

This case explores the origins of a new high-growth, family start-up competing in a traditional industry. Teeling Whiskey Company Ltd (TWC) is the brainchild of entrepreneur Jack Teeling. This new venture stems from another high-profile, family based business named Cooley Distillery. Jack was managing director of Cooley Distillery, the business his father founded in 1987. In Cooley Distillery, Jack acquired a wealth of professional experience in whiskey distilling and selling. When the distil...

Clinical Investigation of the Dopaminergic System with PET and FLUORINE-18-FLUORO-L-DOPA.

Science.gov (United States)

Oakes, Terrence Rayford

1995-01-01

Positron Emission Tomography (PET) is a tool that provides quantitative physiological information. It is valuable both in a clinical environment, where information is sought for an individual, and in a research environment, to answer more fundamental questions about physiology and disease states. PET is particularly attractive compared to other nuclear medicine imaging techniques in cases where the anatomical regions of interest are small or when true metabolic rate constants are required. One example with both of these requirements is the investigation of Parkinson's Disease, which is characterized as a presynaptic motor function deficit affecting the striatum. As dopaminergic neurons die, the ability of the striatum to affect motor function decreases. The extent of functional neuronal damage in the small sub-structures may be ascertained by measuring the ability of the caudate and putamen to trap and store dopamine, a neurotransmitter. PET is able to utilize a tracer of dopamine activity, ^ {18}F- scL-DOPA, to quantitate the viability of the striatum. This thesis work deals with implementing and optimizing the many different elements that compose a PET study of the dopaminergic system, including: radioisotope production; conversion of aqueous ^{18}F ^-into [^ {18}F]-F2; synthesis of ^{18}F- scL -DOPA; details of the PET scan itself; measurements to estimate the radiation dosimetry; accurate measurement of a plasma input function; and the quantitation of dopaminergic activity in normal human subjects as well as in Parkinson's Disease patients.

Pašvērtējuma, apmierinātības ar dzīvi un agresijas atšķirības pieaugušajiem ar un bez bērnībā pieredzētas vecāku šķiršanās

OpenAIRE

Ekarte, Marika

2013-01-01

Pētījuma mērķis ir noskaidrot vai pastāv atšķirības starp uzrādītajiem pašvērtējuma, apmierinātības ar dzīvi un agresijas rādītājiem respondentiem ar bērnībā pieredzētu vecāku šķiršanos un respondentiem bez vecāku šķiršanās pieredzes, kontrolējot dzimumu. Pētījuma mērķa noskaidrošanā pielietota pašvērtējuma aptauja (Rosenberg Self-Esteem Scale, RSE, Rosenberg, 1965), apmierinātības ar dzīvi aptauja (Satisfaction with life scales. Diener, 1985), agresijas līmeņa noteikšanai - agre...

Radiolabelling of isopeptide N{sup {epsilon}}-({gamma}-glutamyl)-L-lysine by conjugation with N-succinimidyl-4-[{sup 18}F]fluorobenzoate

Energy Technology Data Exchange (ETDEWEB)

Wuest, F; Hultsch, C; Bergmann, R; Johannsen, B; Henle, T

2003-07-01

The isopeptide N{sup {epsilon}}-({gamma}-glutamyl)-L-lysine 4 was labelled with {sup 18}F via N-succinimidyl-4-[{sup 18}F]fluorobenzoate ([{sup 18}F]SFB). A modified approach for the convenient synthesis of [{sup 18}F]SFB was used, and [{sup 18}F]SFB could be obtained in decay-corrected radiochemical yields of 44-53% (n=20) and radiochemical purity >95% within 40 min after EOB. For labelling N{sup {epsilon}}-({gamma}-glutamyl)-L-lysine with [{sup 18}F]SFB the effects of isopeptide concentration, temperature, and pH were studied to determine the optimum reaction conditions. The coupling reaction was shown to be temperature and pH independent while being strongly affected by the isopeptide concentration. Using the optimized labelling conditions, in a typical experiment 1.3 GBq of [{sup 18}F]SFB could be converted into 447 MBq (46%, decay-corrected) of [{sup 18}F]fluorobenzoylated isopeptide within 45 min, including HPLC purification.

Oxygen Isotope Records in Modern Oyster Shells from Chi Ku, Tainan and Their Implication of Seasonality

Science.gov (United States)

Chen, Y. C.; Mii, H. S.; Li, K. T.

2015-12-01

To exam whether oxygen isotope records of Crassostrea gigasoysters can be used as proxies of environment, 133 cultivated oysters and 21 water samples were collected from Chi Ku area, Tainan City, southern Taiwan in December of 2012, and from March, 2013 to July, 2014. Instrumental air and water temperatures and precipitation records were obtained from a nearest Central Weather Bureau (CWB) station roughly 16 km north of Chi Ku. The oxygen and carbon isotope values of the ligamental area of the modern oyster shells are from -6.92‰ to -0.08‰ (-3.05 ± 1.17‰, N = 2280; 1σ; VPDB) and from -5.57‰ to 0.63‰ (-1.88 ± 0.81‰), respectively. Oxygen isotope values of the water samples are mainly between -0.28‰ and 0.74‰ (0.18 ± 0.29‰, N = 20; 1σ; VSMOW). However, water oxygen isotope value of -2.75‰ was observed for the water sample collected immediately after a typhoon heavy rainfall. Seasonal temperature fluctuation pattern of estimated oxygen isotope temperatures from modern shells is similar to that of CWB instrumental records. However, the oxygen isotope temperatures are respectively about 3 °C and 10°C higher than those of instrumental records for winter and summer. Higher estimated oxygen isotope temperatures are most likely caused by underestimated fraction of freshwater. We analyzed 5 archaeological oyster shells of Siraya culture (500~250B.P.) collected from Wu Chien Tuso North (WCTN) archaeological site of Tainan branch of Southern Taiwan Science Park to infer the harvest season of mollusks. Oxygen isotope values of the ligamental area of the archaeological oyster shells are between -5.98‰ and -1.26‰ (-3.34 ± 1.37‰, N = 60; 1σ), and carbon isotope values are between -3.21‰ and 0.60‰ (-2.04‰ ± 0.55‰). The oxygen isotope records of archaeological oyster shells also showed clear seasonality. Most of the oysters were collected in autumn and winter. Oxygen isotope values of archaeological oyster shells was 1‰ greater than that

Biodistribution and catabolism of 18F-labelled isopeptide N(epsilon)-(gamma-glutamyl)-L-lysine.

Science.gov (United States)

Hultsch, C; Bergmann, R; Pawelke, B; Pietzsch, J; Wuest, F; Johannsen, B; Henle, T

2005-12-01

Isopeptide bonds between the epsilon-amino group of lysine and the gamma-carboxamide group of glutamine are formed during strong heating of pure proteins or, more important, by enzymatic reaction mediated by transglutaminases. Despite the wide use of a microbial transglutaminase in food biotechnology, up to now little is known about the metabolic fate of the isopeptide N(epsilon)-(gamma-glutamyl)-L-lysine. In the present study, N-succinimidyl-4-[(18)F]fluorobenzoate was used to modify N(epsilon)-(gamma-glutamyl)-L-lysine at each of its two alpha-amino groups, resulting in the 4-[(18)F]fluorobenzoylated derivatives, for which biodistribution, catabolism, and elimination were investigated in male Wistar rats. A significant different biochemical behavior of the two labelled isopeptides was observed in terms of in vitro stability, in vivo metabolism as well as biodistribution. The results suggest that the metabolic fate of isopeptides is likely to be dependent on how they are reabsorbed - free or peptide bound.

Türkiye’de Çalışan Y Kuşağında İş Tatmini-Motivasyon İlişkisi

OpenAIRE

Saracel, Nüket; Taşseven, Özlem; Kaynak, Ece

2016-01-01

Bilgi çağı olarak nitelenen yirmi birinci yüzyılda, bilgi ve insan organizasyonların en önemli sermayesihaline gelmiştir. Üretim kaynakları içerisinde insanın öneminin artması şirketlerin yönetiminde insangücünün motivasyonu ve iş tatminine ilişkin konuların özel önem taşıyan konular olmasını beraberindegetirmiştir. Birbirlerine yakın zamanlarda doğan insanların benzer özellikler taşıması kuşak kavramınıortaya çıkarmıştır. Her bir kuşağın farklı özelliklerinin olması, organizasyonel sistemler...

Determination of The Adaptation of Some Azolla (Azolla anabaena L) Genotypes to The Mediterranean and Aegean Coastline Ecological Conditions

OpenAIRE

GEVREK, Mithat Nuri

2015-01-01

u çalışmada bazı azolla (Azolla anabaena L.) genotiplerinin Akdeniz-Ege kıyı kuşağına adaptasyonunun belirlenmesi amaçlanmıştır. Araştırma 20022003 ve 2003-2004 yıllarında Ege Üniversitesi Ziraat Fakültesi’nin Menemen

Influence of the composition of aqueous dimethylsulfoxide solvent on thermodynamics of complexing between 18-crown-6-ether and D,L-alanine

Science.gov (United States)

Usacheva, T. R.; Kuzmina, I. A.; Sharnin, V. A.; Chernov, I. V.; Matteoli, E.

2012-07-01

Standard thermodynamic parameters (log K o, Δr H o, TΔr S o) of complexing 18-crown-6 ether (18C6) with D,L-alanine (Ala) in mixed water-dimethysulfoxide (H2O-DMSO) solvents are calculated on the basis of calorimetric titration results. A rise in the DMSO concentration in mixed solvent is found to increase stability and increase the exothermicity of the formation of [Ala-18C6] molecular complex. Changes in the reaction energetic are shown to be determined by changes in the solvation state of 18C6 that is the characteristic of the reactions of molecular complex formation between 18C6 and D,L-alanine or glycine in water-organic solvents.

Impact of tropospheric scintillation in the Ku/K bands on the communications between two LEO satellites in a radio occultation geometry

DEFF Research Database (Denmark)

Martini, Enrica; Freni, A.; Facheris, L.

2006-01-01

A theoretical analysis of the impact of clear-air tropospheric scintillation on a radio occultation link between two low Earth orbit satellites in K- and Ku-bands is presented, with particular reference to differential approaches for the measure of the total content of water vapor. The troposphere...

Influence of blood-brain barrier permeability on O-(2-{sup 18}F-fluoroethyl)-L-tyrosine uptake in rat gliomas

Energy Technology Data Exchange (ETDEWEB)

Stegmayr, Carina; Bandelow, Ulrike; Oliveira, Dennis; Lohmann, Philipp; Willuweit, Antje; Galldiks, Norbert; Luebke, Joachim H.R. [Institute of Neuroscience and Medicine, Forschungszentrum Juelich, Juelich (Germany); Filss, Christian; Ermert, Johannes; Langen, Karl-Josef [Institute of Neuroscience and Medicine, Forschungszentrum Juelich, Juelich (Germany); RWTH/University Hospital Aachen, Department of Nuclear Medicine and Neurology, Aachen (Germany); Shah, N. Jon [Institute of Neuroscience and Medicine, Forschungszentrum Juelich, Juelich (Germany); RWTH/University Hospital Aachen, Department of Nuclear Medicine and Neurology, Aachen (Germany); Juelich-Aachen Research Alliance (JARA) - Section JARA-Brain, Aachen (Germany)

2017-03-15

O-(2-{sup 18}F-fluoroethyl)-L-tyrosine ({sup 18}F-FET) is an established tracer for the diagnosis of brain tumors with PET. This study investigates the influence of blood-brain barrier (BBB) permeability on {sup 18}F-FET uptake in two rat glioma models and one human xenograft model. F98 glioma, 9L gliosarcoma or human U87 glioblastoma cells were implanted into the striatum of 56 Fischer or RNU rats. Thereafter, animals were divided into a control group and a group receiving injections of the glucocorticoid dexamethasone (Dex). After 12-13 days of tumor growth animals received injection of Evans blue dye (EBD) to visualize BBB disturbance and underwent {sup 18}F-FET PET followed by autoradiography. Time activity curves, standardized uptake values (SUV) and Tumor-to-brain ratios (TBR) of {sup 18}F-FET uptake [18-61 min post injection (p.i.)] were evaluated using a volume-of-Interest (VOI) analysis. BBB disturbance was quantitatively evaluated by EBD fluorescence. The membrane gaps of blood vessel endothelial tight junctions were measured using electron microscopy to visualize ultrastructural BBB alterations in one untreated and one Dex treated F98 glioma. Data were analyzed by two-way ANOVAs. In Dex treated animals EBD extravasation was significantly reduced in 9L (P < 0.001) and U87 (P = 0.008) models and showed a trend in F98 models (P = 0.053). In contrast, no significant differences of {sup 18}F-FET uptake were observed between Dex treated animals and control group except a decrease of the TBR in the 9L tumor model in PET (P < 0.01). Ultrastructural evaluation of tumor blood vessel endothelia revealed significant reduction of the cleft diameter between endothelial cells after Dex treatment in F98 model (P = 0.010). Despite a considerable reduction of BBB permeability in rat gliomas after Dex treatment, no relevant changes of {sup 18}F-FET uptake were noted in this experimental study. Thus, {sup 18}F-FET uptake in gliomas appears to be widely independent of the

Prokaryotic Homologs of the Eukaryotic 3-Hydroxyanthranilate 3,4-Dioxygenase and 2-Amino-3-Carboxymuconate-6-Semialdehyde Decarboxylase in the 2-Nitrobenzoate Degradation Pathway of Pseudomonas fluorescens Strain KU-7†

OpenAIRE

Muraki, Takamichi; Taki, Masami; Hasegawa, Yoshie; Iwaki, Hiroaki; Lau, Peter C. K.

2003-01-01

The 2-nitrobenzoic acid degradation pathway of Pseudomonas fluorescens strain KU-7 proceeds via a novel 3-hydroxyanthranilate intermediate. In this study, we cloned and sequenced a 19-kb DNA locus of strain KU-7 that encompasses the 3-hydroxyanthranilate meta-cleavage pathway genes. The gene cluster, designated nbaEXHJIGFCDR, is organized tightly and in the same direction. The nbaC and nbaD gene products were found to be novel homologs of the eukaryotic 3-hydroxyanthranilate 3,4-dioxygenase a...

Remote-controlled module-assisted synthesis of O-(2-[18F]fluoroethyl)-L-tyrosine as tumor PET tracer using two different radiochemical routes

International Nuclear Information System (INIS)

Wang Mingwei; Yin Duanzhi; Zhang Lan; Zhou Wei; Wang Yongxian

2006-01-01

The positron-emitter fluorine-18 labeled amino acid O-(2-[ 18 F]fluoroethyl)-L-tyrosine ([ 18 F]FET) has shown very promising perspectives for brain tumor diagnosis with positron emission tomography (PET). There have been two existing preparation routes of [ 18 F]FET named direct nucleophilic radiofiuorination of protected L-tyrosine and radiofiuoroallcylation of unprotected L-tyrosine, respectively. A general module was designed specifically for the routine synthesis of [ 18 F]FET, which could be suitable for the present two chemical methods with simple modifications. The fluorinated intermediates and the final product were separated and purified using solid phase extraction (SPE) on the Sep-Pak silica plus cartridge instead of the time-consuming high performance liquid chromatography (HPLC) procedures. The total synthesis time was about 50-60 rain with good radiochemical yield (about 20-40%, no-decay-corrected) and good radiochemical purity (more than 97%) for both the synthetic methods. (authors)

Evaluation of F-18-labeled amino acid derivatives and [18F]FDG as PET probes in a brain tumor-bearing animal model

International Nuclear Information System (INIS)

Wang, H.-E.; Wu, S.-Y.; Chang, C.-W.; Liu, R.-S.; Hwang, L.-C.; Lee, T.-W.; Chen, J.-C.; Hwang, J.-J.

2005-01-01

2-Deoxy-2-[ 18 F]fluoro-D-glucose ([ 18 F]FDG) has been extensively used as positron emission tomography (PET) tracer in clinical tumor imaging. This study compared the pharmacokinetics of two 18 F-labeled amino acid derivatives, O-2-[ 18 F]fluoroethyl-L-tyrosine (L-[ 18 F]FET) and 4-borono-2-[ 18 F]fluoro-L-phenylalanine-fructose (L-[ 18 F]FBPA-Fr), to that of [ 18 F]FDG in an animal brain tumor model. Methods: A self-modified automated PET tracer synthesizer was used to produce no-carrier-added (nca) L-[ 18 F]FET. The cellular uptake, biodistribution, autoradiography and microPET imaging of L-[ 18 F]FET, L-[ 18 F]FBPA-Fr and [ 18 F]FDG were performed with F98 glioma cell culture and F98 glioma-bearing Fischer344 rats. Results: The radiochemical purity of L-[ 18 F]FET was >98% and the radiochemical yield was 50% in average of 16 runs. The uptake of L-[ 18 F]FET and L-[ 18 F]FBPA-Fr in the F98 glioma cells increased rapidly for the first 5 min and reached a steady-state level after 10 min of incubation, whereas the cellular uptake of [ 18 F]FDG kept increasing during the study period. The biodistribution of L-[ 18 F]FET, L-[ 18 F]FBPA-Fr and [ 18 F]FDG in the brain tumors was 1.26±0.22, 0.86±0.08 and 2.77±0.44 %ID/g at 60 min postinjection, respectively, while the tumor-to-normal brain ratios of L-[ 18 F]FET (3.15) and L-[ 18 F]FBPA-Fr (3.44) were higher than that of [ 18 F]FDG (1.44). Both microPET images and autoradiograms of L-[ 18 F]FET and L-[ 18 F]FBPA-Fr exhibited remarkable uptake with high contrast in the brain tumor, whereas [ 18 F]FDG showed high uptake in the normal brain and gave blurred brain tumor images. Conclusion: Both L-[ 18 F]FET and L-[ 18 F]FBPA-Fr are superior to [ 18 F]FDG for the brain tumor imaging as shown in this study with microPET

An automated system for the synthesis of L-6-[18F]fluorodopa

International Nuclear Information System (INIS)

Ruth, T.; Adam, M.; Jivan, S.; Morris, D.; Tyldesley, S.

1990-01-01

The PET chemistry group at TRIUMF has completely automated the synthesis of L-6-[ 18 F]fluorodopa. This was done to reduce the exposure of lab technicians to radioactive and corrosive chemicals used in the process. It also improves reliability and reproducibility of the synthesis. The automation is controlled by an IBM Personal Computer AT running the MS-DOS Operating System. The software for the synthesis was written using the Microsoft QuickBASIC Compiler. Graphic display features were created using the Connell Scientific Graphics EGA Toolkit

Zileņu (Vaccinium uliginosum L.), melleņu (Vaccinium myrtillus L.) un krūmelleņu (Vaccinium corymbosum) ķīmiskais sastāvs un bioloģiskā aktivitāte

OpenAIRE

Hūna, Agnese

2015-01-01

Zileņu Vaccinium uliginosum L. un melleņu Vaccinium myrtillus L. izplatība ir Eiropas ziemeļu augsto purvu un mitro mežu areālā, skuju koku un jaukto koku mežos, īpaši retainēs un izcirtumos, savukārt krūmellenes Vaccinium corymbosum tiek audzētas kā kultūraugi. Ķīmiskais sastāvs un bioloģiskā aktivitāte, kā arī dažādu vitamīnu un vielu saturs, ogās ir ļoti augsts. Zilās ogas potenciāli labvēlīgi iedarbojas uz cilvēku veselību gan kā profilakses līdzeklis, gan kā ārstniecības līdzeklis. Neska...

Room Temperature Thin Film Ba(x)Sr(1-x)TiO3 Ku-Band Coupled MicrostripPhase Shifters: Effects of Film Thickness, Doping, Annealing and Substrate Choice

Science.gov (United States)

VanKeuls, F. W.; Mueller, C. H.; Miranda, F. A.; Romanofsky, R. R.; Canedy, C. L.; Aggarwal, S.; Venkatesan, T.; Ramesh, R.; Horwitz, S.; Chang, W.

1999-01-01

We report on measurements taken on over twenty Ku-band coupled microstrip phase shifters (CMPS) using thin ferroelectric films of Ba(x)Sr(1-x)TiO3. This CMPS design is a recent innovation designed to take advantage of the high tunability and tolerate the high dielectric constant of ferroelectric films at Ku- and K-band frequencies. These devices are envisioned as a component in low-cost steerable beam phased area antennas, Comparisons are made between devices with differing film thickness, annealed vs unannealed, Mn-doped vs. undoped, and also substrates of LaAlO3 and MgO. A comparison between the CMPS structure and a CPW phase shifter was also made oil the same ferroelectric film.

Biological evaluation of [18F]-nifedipine as a novel PET tracer for L-type calcium channel imaging

International Nuclear Information System (INIS)

Sadeghpour, H.; Jalilian, A.R.; Akhlaghi, M.; Mirzaii, M.; Saddadi, F.; Shafiee, A.; Miri, R.

2008-01-01

Due to interesting role of dihydropyridines in cardiovascular diseases and drug resistance studies and lack of a fluorine-18 labeled imaging agent for L-type calcium channel studies, this study was designed. [ 18 F] Dimethyl 2 - (fluoromethyl) - 6 - methyl - 4 - (2 - nitrophenyl) - 1,4 - dihydropyridine - 3,5 - dicarboxylate 2 was prepared in no-carrier-added (n.c.a.) form from a starting brominated compound in one step at 80 o C in Kryptofix2.2.2/[ 18 F]. Compound 2 was administered to normal rats via their tail veins for preliminary biodistribution studies and the ID/g % of the labeled compound was determined up to 3 h post injections. Coincidence images were obtained in rats 5 to 120 min. Radiofluorination on bromo precursor gave a fluorinated compound in 95 % radiochemical purity and a 8% yield shown by RTLC and HPLC. Biodistribution studies showed that the tracer is accumulated in the heart in the first few minutes, followed by metabolism resulting in very soluble 18 F-containing metabolites eliminated through the urinary tract. In coincidence images, the target organ was shown to be the heart. Lung had high accumulation possibly due to the presence of Ca 2+ channels and/or hydrolyzing enzymes showing a significant myocardial uptake at 120 min. The data demonstrates a significant agreement with the reported L-type calcium channels throughout the animal body. To our knowledge, this is the first example of 18 F-DHPs in the literature. (authors)

Proliferation Potential of 18-Month-Old Callus of Ananas comosus L. cv. Moris

Directory of Open Access Journals (Sweden)

A.E. De Silva

2006-01-01

Full Text Available Differential effect of plant growth regulators and additives in proliferation of 18-month-old calli of Ananas comosus L. cv. Moris were assessed in vitro. The proliferation of callus relied on the growth regulators and additives. Of the different auxins supplemented in the Murashige and Skoog (MS media, 32.22 μM α-naphthaleneacetic acid (NAA gave the highest mean fresh weight of callus (46.817 g. Medium supplemented with 2,4-dichlorophenoxyacetic acid (2,4-D was inferior to NAA, while b-naphthoxy acetic acid (BNOA and p-chlorophenoxy acetic acid (4-CPA were not effective in proliferating 18-months old callus. Addition of casein hydrolysate and coconut water to NAA supplemented medium showed better proliferation and production of callus. However, in terms of callus production, NAA at 32.22 μM was economically better.

Redistribuce hliníku a uhlíku ve svarech ocelí v intervalu teplot 500-1100 stupňů C (0,34 hm.

Czech Academy of Sciences Publication Activity Database

Stránský, K.; Million, Bořivoj; Foret, R.; Michalička, Petr; Rek, A.

2003-01-01

Roč. 76, č. 290 (2003), s. 213-221 ISSN 1429-6055. [Mezinárodní sympózium Struktura a vlastnosti konstrukčních materiálů /18./. Svratka, 25.11.2003-27.11.2003] R&D Projects: GA ČR GA106/01/0379; GA ČR GA106/01/0382 Institutional research plan: CEZ:AV0Z2041904 Keywords : aluminium and carbon diffusion * steel weldments Subject RIV: JG - Metallurgy

Redistribuce hliníku a uhlíku ve svarech ocelí v intervalu teplot 500-1100 stupňů C (0,34 hm.

Czech Academy of Sciences Publication Activity Database

Stránský, K.; Million, Bořivoj; Foret, R.; Michalička, Petr; Rek, A.

2003-01-01

Roč. 76, č. 290 (2003), s. 213-216 ISSN 1429-6055. [Mezinárodní sympózium Struktura a vlastnosti konstrukčních materiálů /18./. Svratka, 25.11.2003-27.11.2003] R&D Projects: GA ČR GA106/01/0379; GA ČR GA106/01/0382 Institutional research plan: CEZ:AV0Z2041904 Keywords : aluminium and carbon diffusion * steel weldments Subject RIV: JG - Metallurgy

Focusing electrode and coaxial reflector used for reducing the guiding magnetic field of the Ku-band foilless transit-time oscillator

Energy Technology Data Exchange (ETDEWEB)

Ling, Junpu; Zhang, Jiande; He, Juntao, E-mail: hejuntao12@163.com; Wang, Lei; Deng, Bingfang [College of Optoelectronic Science and Engineering, National University of Defense Technology, Changsha 410073 (China)

2014-08-15

Based on the theoretical analysis of the intense relativistic electron beam propagation in the coaxial drift-tube, a focusing electrode and a coaxial reflector is proposed to lessen the demand of the coaxial Ku-band foilless transit-time oscillator (TTO) for the guiding magnetic field. Moreover, a Ku-band TTO with the focusing electrode and the coaxial reflector is designed and studied by particle in cell simulation. When the diode voltage is 390 kV, the beam current 7.8 kA, and the guiding magnetic field is only 0.3 T, the device can output 820 MW microwave pulse at 14.25 GHz by means of the simulation. However, for the device without them, the output power is only 320 MW. The primary experiments are also carried out. When the guiding magnetic field is 0.3 T, the output power of the device with the focusing electrode and the coaxial reflector is double that of the one without them. The simulation and experimental results prove that the focusing electrode and the coaxial reflector are effective on reducing the guiding magnetic field of the device.

Design studies of the Ku-band, wide-band Gyro-TWT amplifier

Science.gov (United States)

Jung, Sang Wook; Lee, Han Seul; Jang, Kwong Ho; Choi, Jin Joo; Hong, Yong Jun; Shin, Jin Woo; So, Jun Ho; Won, Jong Hyo

2014-02-01

This paper reports a Ku-band, wide band Gyrotron-Traveling-wave-tube(Gyro-TWT) that is currently being developed at Kwangwoon University. The Gyro-TWT has a two stage linear tapered interaction circuit to obtain a wide operating bandwidth. The linearly-tapered interaction circuit and nonlinearly-tapered magnetic field gives the Gyro-TWT a wide operating bandwidth. The Gyro-TWT bandwidth is 23%. The 2d-Particle-in-cell(PIC) and MAGIC2d code simulation results are 17.3 dB and 24.34 kW, respectively for the maximum saturated output power. A double anode MIG was simulated with E-Gun code. The results were 0.7 for the transvers to the axial beam velocity ratio (=alpha) and a 2.3% axial velocity spread at 50 kV and 4 A. A magnetic field profile simulation was performed by using the Poisson code to obtain the grazing magnetic field of the entire interaction circuit with Poisson code.

The differences in heparin binding for the C-terminal basic-sequence-rich peptides of HPV-16 and HPV-18 capsid protein L1

International Nuclear Information System (INIS)

Sun Jian; Yu Jisheng; Yu Zhiwu; Zha Xiao; Wu Yuqing

2012-01-01

Graphial abstract: The differences in heparin binding for the C-terminal basic-sequence-rich peptides of HPV-16 and HPV-18 capsid protein L1. Highlights: ► Several driving forces contribute to the interaction between heparin and peptides. ► C-terminal of HPV L1 is a potential candidate for the attachment to host cells. ► The C-terminal peptides of HPV-16 and -18 L1 have different heparin-binding. ► The different heparin-binding provides an explanation for the distinct prevalences. - Abstract: The high-risk types of human papillomaviruses (HPV) HPV-16 and -18 are the predominant types associated with cervical cancer. HPV-16 and -18 account for about 50% and 20%, respectively, of cervical cancers worldwide. While the reason and molecular mechanism of the distinct prevalence and distributions between them remain poorly understood, the binding affinity of cell surface receptor with capsid proteins, especially L1, may be involved. We examined heparin binding with two synthetic peptides corresponding to the 14 amino acid C-terminal peptides of HPV-16 and -18 L1 with the goal of comparing the equivalent residues in different HPV types. Using isothermal titration calorimetry (ITC) and static right-angle light scattering (SLS), we determined the binding constant K, reaction enthalpy ΔH, and other thermodynamic parameters in the interaction. Especially, we assessed the role of specific residues in binding with heparin by comparing the NMR spectra of free and heparin-bound peptides.

Impact of Surface Soil Moisture Variations on Radar Altimetry Echoes at Ku and Ka Bands in Semi-Arid Areas

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Christophe Fatras

2018-04-01

Full Text Available Radar altimetry provides information on the topography of the Earth surface. It is commonly used for the monitoring not only sea surface height but also ice sheets topography and inland water levels. The radar altimetry backscattering coefficient, which depends on surface roughness and water content, can be related to surface properties such as surface soil moisture content. In this study, the influence of surface soil moisture on the radar altimetry echo and backscattering coefficient is analyzed over semi-arid areas. A semi-empirical model of the soil’s complex dielectric permittivity that takes into account that small-scale roughness and large-scale topography was developed to simulate the radar echoes. It was validated using waveforms acquired at Ku and Ka-bands by ENVISAT RA-2 and SARAL AltiKa respectively over several sites in Mali. Correlation coefficients ranging from 0.66 to 0.94 at Ku-band and from 0.27 to 0.96 at Ka-band were found. The increase in surface soil moisture from 0.02 to 0.4 (i.e., the typical range of variations in semi-arid areas increase the backscattering from 10 to 15 dB between the core of the dry and the maximum of the rainy seasons.

Small-angle X-ray titration study on the complex formation between 5-S RNA and the L18 protein of the Escherichia coli 50-S ribosome particle

International Nuclear Information System (INIS)

Oesterberg, R.; Garrett, A.

1977-01-01

The 5-S RNA (A) and the L 18 protein (B) from Escherichia coli ribosomes form one single AB complex in the concentration ranges supposed to prevail in vivo; at concentrations of L 18 higher than 40 mM there is some indication for a minor species, most probably an AB 2 species. This is indicated from the X-ray scattering titration data of the 5-S RNA/L 18 system recorded at 21 0 C in ribosomal reconstitution buffer. As a result of the 1 : 1 complex formation, there is a relatively small but defined increase in the radius of gyration from 3.61 to 3.85 nm. This result as well as the experimental scattering curve can be explained by models where it is assumed that the elongated L 18 model is quite far from the electron density centre and where protein L 18 interacts with one or both of the minor arms of the supposed Y-shaped 5-S RNA molecule. (orig.) [de

Gaistošo organisko savienojumu emisijas no kuņģa vēža audiem un to potenciālā bioloģiskā saistība

OpenAIRE

Aronsson, Dan Erik

2018-01-01

Gaistošā organiskā savienojuma (VOC) emisija, ko var novērot izelpā, ir strauji augoša diagnostikas metode audzēju izmeklēšanā. VOC ir savienojums, kam istabas temperatūrā ir augsts tvaika spiediens, kas veicina tā iztvaikošanu gāzes formā. Šo gāzi var noteikt cilvēka audos un šķidrumos.( Haick et al 2014) Galvenokārt ir pētīta VOC saistība ar plaušu vēzi. Taču aizvien vairāk tiek veikti pētījumi, lai noteiktu, kādas ir iespējas VOC pielietot arī kuņģa audzēja gadījumā. Tā kā VOC molekula sp...

cis-4-[{sup 18}F]-Fluoro-L-proline fails to detect peripheral tumors in humans

Energy Technology Data Exchange (ETDEWEB)

Stoffels, Gabriele; Pauleit, Dirk [Institute of Neuroscience and Biophysics-Medicine, Research Centre Juelich, D-52425 Juelich, FRG (Germany); Haas, Rainer; Kobbe, Guido [Department of Oncology, Hematology, and Clinical Immunology, Heinrich-Heine-University Duesseldorf, FRG (Germany); Salber, Dagmar [C. and O. Vogt Institute of Brain Research, Heinrich-Heine-University Duesseldorf, FRG (Germany); Hamacher, Kurt; Coenen, Heinz H. [Institute of Neuroscience and Biophysics - Nuclear Chemistry, Research Centre Juelich, Juelich, FRG (Germany); Langen, Karl-Josef [Institute of Neuroscience and Biophysics-Medicine, Research Centre Juelich, D-52425 Juelich, FRG (Germany)], E-mail: k.j.langen@fz-juelich.de

2008-11-15

System A amino acid transport is increased in transformed and malignant cells. The amino acid 4-cis[{sup 18}F]fluoro-L-proline (cis-[{sup 18}F]FPro) has been shown to be a substrate of the System A amino acid carrier. In this pilot study, we investigated the diagnostic potential of cis-[{sup 18}F]FPro in patients with various tumors in comparison with [{sup 18}F]fluorodeoxyglucose-positron emission tomography (FDG-PET). Methods: Eight patients (seven females, one male, age range 43-77 years) with large primary, recurrent or metastatic tumors of different histologies were included in this study. One patient had a recurrent non-Hodgkin lymphoma; two patients, metastatic colon or rectal cancer; one, a metastatic endometrial cancer; one, a multiple myeloma; one, an Ewing sarcoma; one, a metastatic breast cancer and one, a gastrointestinal stromal tumor. PET scans of the trunk were acquired at 1 h after intravenous injection of 400 MBq cis-[{sup 18}F]FPro and compared to PET scans with [{sup 18}F]FDG. Results: None of the tumors or metastatic lesions in this series of patients demonstrated relevant uptake of cis-[{sup 18}F]FPro. In contrast, all tumors with exception of the multiple myeloma showed an intensive uptake of [{sup 18}F]FDG. The mean standardized uptake value of cis-[{sup 18}F]FPro in the tumor or metastases was significantly lower than that of [{sup 18}F]FDG uptake (1.7{+-}0.6 vs. 5.7{+-}3.0; n=8; P<.01). Conclusion: Although other System A-specific tracers have shown relevant tumor uptake, cis-[{sup 18}F]FPro fails to detect most types of human tumors. Based on these results, we cannot recommend a further evaluation of this tracer as a tumor-seeking agent.

Fully automated one-pot radiosynthesis of O-(2-[{sup 18}F]fluoroethyl)-L-tyrosine on the TracerLab FX{sub FN} module

Energy Technology Data Exchange (ETDEWEB)

Bourdier, Thomas, E-mail: bts@ansto.gov.au [LifeSciences, Australian Nuclear Science and Technology Organisation, Locked Bag 2001, Kirrawee DC NSW 2232, Sydney (Australia); Greguric, Ivan [LifeSciences, Australian Nuclear Science and Technology Organisation, Locked Bag 2001, Kirrawee DC NSW 2232, Sydney (Australia); Roselt, Peter [Centre for Molecular Imaging, Peter MacCallum Cancer Centre, 12 St Andrew' s Place, East Melbourne, VIC, 3002 (Australia); Jackson, Tim; Faragalla, Jane; Katsifis, Andrew [LifeSciences, Australian Nuclear Science and Technology Organisation, Locked Bag 2001, Kirrawee DC NSW 2232, Sydney (Australia)

2011-07-15

Introduction: An efficient fully automated method for the radiosynthesis of enantiomerically pure O-(2-[{sup 18}F]fluoroethyl)-L-tyrosine ([{sup 18}F]FET) using the GE TracerLab FX{sub FN} synthesis module via the O-(2-tosyloxyethyl)-N-trityl-L-tyrosine tert-butylester precursor has been developed. Methods: The radiolabelling of [{sup 18}F]FET involved a classical [{sup 18}F]fluoride nucleophilic substitution performed in acetonitrile using potassium carbonate and Kryptofix 222, followed by acid hydrolysis using 2N hydrochloric acid. Results: [{sup 18}F]FET was produced in 35{+-}5% (n=22) yield non-decay-corrected (55{+-}5% decay-corrected) and with radiochemical and enantiomeric purity of >99% with a specific activity of >90 GBq/{mu}mol after 63 min of radiosynthesis including HPLC purification and formulation. Conclusion: The automated radiosynthesis provides high and reproducible yields suitable for routine clinical use.

Zamyšlení nad charakterem vůdčí vrstvy městského obyvatelstva na příkladu Brna v raném novověku. Diskusní příspěvek

Czech Academy of Sciences Publication Activity Database

Sulitková, Ludmila

2004-01-01

Roč. 22, - (2004), s. 243-260, 383-384 ISSN 0231-7443. [Pražské městské elity středověku a raného novověku - jejich proměny, zázemí a kulturní profil. Praha, 01.10.2002-02.10.2002] Institutional research plan: CEZ:AV0Z8077915 Keywords : municipal elites * Early Modern Ages * Brno Subject RIV: AB - History

Low-loss negative index metamaterials for X, Ku, and K microwave bands

Directory of Open Access Journals (Sweden)

David A. Lee

2015-04-01

Full Text Available Low-loss, negative-index of refraction metamaterials were designed and tested for X, Ku, and K microwave frequency bands. An S-shaped, split-ring resonator was used as a unit cell to design homogeneous slabs of negative-index metamaterials. Then, the slabs of metamaterials were cut unto prisms to measure experimentally the negative index of refraction of a plane electromagnetic wave. Theoretical simulations using High-Frequency Structural Simulator, a finite element equation solver, were in good agreement with experimental measurements. The negative index of refraction was retrieved from the angle- and frequency-dependence of the transmitted intensity of the microwave beam through the metamaterial prism and compared well to simulations; in addition, near-field electromagnetic intensity mapping was conducted with an infrared camera, and there was also a good match with the simulations for expected frequency ranges for the negative index of refraction.

A novel beta-glucosidase from the cell wall of maize (Zea mays L.): rapid purification and partial characterization

Science.gov (United States)

Nematollahi, W. P.; Roux, S. J.

1999-01-01

Plants have a variety of glycosidic conjugates of hormones, defense compounds, and other molecules that are hydrolyzed by beta-glucosidases (beta-D-glucoside glucohydrolases, E.C. 3.2.1.21). Workers have reported several beta-glucosidases from maize (Zea mays L.; Poaceae), but have localized them mostly by indirect means. We have purified and partly characterized a 58-Ku beta-glucosidase from maize, which we conclude from a partial sequence analysis, from kinetic data, and from its localization is not identical to any of those already reported. A monoclonal antibody, mWP 19, binds this enzyme, and localizes it in the cell walls of maize coleoptiles. An earlier report showed that mWP19 inhibits peroxidase activity in crude cell wall extracts and can immunoprecipitate peroxidase activity from these extracts, yet purified preparations of the 58 Ku protein had little or no peroxidase activity. The level of sequence similarity between beta-glucosidases and peroxidases makes it unlikely that these enzymes share epitopes in common. Contrary to a previous conclusion, these results suggest that the enzyme recognized by mWP19 is not a peroxidase, but there is a wall peroxidase closely associated with the 58 Ku beta-glucosidase in crude preparations. Other workers also have co-purified distinct proteins with beta-glucosidases. We found no significant charge in the level of immunodetectable beta-glucosidase in mesocotyls or coleoptiles that precedes the red light-induced changes in the growth rate of these tissues.

Generation, Transformation and Place in Inga Iwasiów’s Novels Bambino (2008 and Ku słońcu (2010

Directory of Open Access Journals (Sweden)

Ursula PHILLIPS

2012-06-01

Full Text Available This chapter will discuss two novels by contemporary writer Inga Iwasiów (b. 1963, Bambino (2008 and Ku słońcu [Towards the Sun] (2010, in the context of geopolitical, ideological, social and psycho-cultural transformations as they specifically affect different generations of inhabitants of the Polish city of Szczecin (pre-1945 German Stettin from 1945 until the first decade of the 21st century. Bambino covers the years 1945–1981, but also contains flashbacksto pre-war memory of Stettin and to the suppressed experiences of the new post-war inhabitants, as well as ‘flash-forwards’ to post-1989, post-communist reality; Ku słońcu covers 1981 to the first decade of 2000s. It will show how the novels portray these transformations through the experience primarily of women (but not only — in Bambino, through the main protagonists: Ula (formerly Ulrike, Anna and Marysia, and through that of the hidden narrator Magda (Marysia’s daughter born in the same year as the author, Iwasiów, 1963; and in Ku słońcu, primarily through the experience of Magda herself, as well as through that of two generations of ‘feminist’ academics: Małgorzata and Sylwia (in which it is hard not to perceive the personal experience of the author, though she is at pains to emphasize elsewhere that her work is a collective biography of the city, not so much of herself. The analysis follows Katarzyna Chmielewska’s supposition that contemporary Polish fiction dealing with the past ‘constantly oscillates between memory and genealogy’, and that it raises raw issues not yet addressed by historians; it also derives inspiration from the new ‘postdependency’ studiesproposed by Hanna Gosk and Ryszard Nycz. It also attempts to capture the specific nature of Iwasiów’s use of language, her style of feminism, her method of portraying place, and the connections in her prose between place and memory.

Akadēmiskās pašregulācijas saistība ar pusaudžu personības iezīmēm un vecāku audzināšanas stiliem

OpenAIRE

Iliško, Judīte

2016-01-01

Maģistra darba pētījuma mērķis bija noskaidrot, kāda saistība pastāv starp pusaudžu pašnovērtēto akadēmisko pašregulāciju, vecāku audzināšanas stiliem un pusaudžu personības iezīmēm, kā arī, vai pastāv dzimuma atšķirības starp pusaudžu pašnovērtēto akadēmisko pašregulāciju, vecāku audzināšanas stiliem un personības iezīmēm, un, cik lielā mērā pusaudžu personības iezīmes un vecāku audzināšanas stili prognozē pusaudžu akadēmisko pašregulāciju. Pētījumā piedalījās 225 7.-8.klašu skolēni no vien...

Waldenström's macroglobulinemia harbors a unique proteome where Ku70 is severely underexpressed as compared with other B-lymphoproliferative disorders

International Nuclear Information System (INIS)

Perrot, A; Pionneau, C; Azar, N; Baillou, C; Lemoine, F M; Leblond, V; Merle-Béral, H; Béné, M-C; Herbrecht, R; Bahram, S; Vallat, L

2012-01-01

Waldenström's macroglobulinemia (WM) is a clonal B-cell lymphoproliferative disorder (LPD) of post-germinal center nature. Despite the fact that the precise molecular pathway(s) leading to WM remain(s) to be elucidated, a hallmark of the disease is the absence of the immunoglobulin heavy chain class switch recombination. Using two-dimensional gel electrophoresis, we compared proteomic profiles of WM cells with that of other LPDs. We were able to demonstrate that WM constitutes a unique proteomic entity as compared with chronic lymphocytic leukemia and marginal zone lymphoma. Statistical comparisons of protein expression levels revealed that a few proteins are distinctly expressed in WM in comparison with other LPDs. In particular we observed a major downregulation of the double strand repair protein Ku70 (XRCC6); confirmed at both the protein and RNA levels in an independent cohort of patients. Hence, we define a distinctive proteomic profile for WM where the downregulation of Ku70—a component of the non homologous end-joining pathway—might be relevant in disease pathophysiology

Diagnostic usefulness of 18F-FAMT PET and L-type amino acid transporter 1 (LAT1) expression in oral squamous cell carcinoma

International Nuclear Information System (INIS)

Nobusawa, Aiko; Kim, Mai; Kaira, Kyoichi; Miyashita, Go; Negishi, Akihide; Yokoo, Satoshi; Oriuchi, Noboru; Higuchi, Tetsuya; Tsushima, Yoshito; Kanai, Yoshikatsu; Oyama, Tetsunari

2013-01-01

l-[3- 18 F]-α-Methyltyrosine ( 18 F-FAMT) was developed as an amino acid tracer for PET imaging to provide better specificity than 2-[ 18 F]fluoro-2-deoxy-d-glucose ( 18 F-FDG) PET for cancer diagnosis. We investigated the diagnostic usefulness of 18 F-FAMT in oral squamous cell carcinoma (OSCC). The correlation between tumour uptake of 18 F-FAMT and L-type amino acid transporter 1 (LAT1) expression was determined. The study group comprised 68 OSCC patients who underwent both 18 F-FAMT and 18 F-FDG PET. Resected tumour sections were stained by immunohistochemistry for LAT1, CD98 and Ki-67, and microvessel density was determined in terms of CD34 and p53 expression. The sensitivity of primary tumour detection by 18 F-FAMT and 18 F-FDG PET was 98 % and 100 %, respectively. The sensitivity, specificity and accuracy of 18 F-FAMT PET for detecting malignant lymph nodes were 68 %, 99 % and 97 %, respectively, and equivalent values for 18 F-FDG PET were 84 %, 94 % and 94 %, respectively. The specificity and accuracy of 18 F-FAMT were significantly higher than those of 18 F-FDG. The uptake of 18 F-FAMT was significantly correlated with LAT1 expression, cell proliferation and advanced stage. The expression of LAT1 in OSCC cells was closely correlated with CD98 levels, cell proliferation and angiogenesis. 18 F-FAMT PET showed higher specificity for detecting malignant lesions than 18 F-FDG PET. The uptake of 18 F-FAMT by OSCC cells can be determined by the presence of LAT1 expression and tumour cell proliferation. (orig.)

Dual-time-point O-(2-[18F]fluoroethyl)-L-tyrosine PET for grading of cerebral gliomas

International Nuclear Information System (INIS)

Lohmann, Philipp; Herzog, Hans; Rota Kops, Elena; Stoffels, Gabriele; Judov, Natalie; Filss, Christian; Tellmann, Lutz; Galldiks, Norbert; Weiss, Carolin; Sabel, Michael; Coenen, Heinz Hubert; Shah, Nadim Jon; Langen, Karl-Josef

2015-01-01

We aimed to evaluate the diagnostic potential of dual-time-point imaging with positron emission tomography (PET) using O-(2-[ 18 F]fluoroethyl)-L-tyrosine ( 18 F-FET) for non-invasive grading of cerebral gliomas compared with a dynamic approach. Thirty-six patients with histologically confirmed cerebral gliomas (21 primary, 15 recurrent; 24 high-grade, 12 low-grade) underwent dynamic PET from 0 to 50 min post-injection (p.i.) of 18 F-FET, and additionally from 70 to 90 min p.i. Mean tumour-to-brain ratios (TBR mean ) of 18 F-FET uptake were determined in early (20-40 min p.i.) and late (70-90 min p.i.) examinations. Time-activity curves (TAC) of the tumours from 0 to 50 min after injection were assigned to different patterns. The diagnostic accuracy of changes of 18 F-FET uptake between early and late examinations for tumour grading was compared to that of curve pattern analysis from 0 to 50 min p.i. of 18 F-FET. The diagnostic accuracy of changes of the TBR mean of 18 F-FET PET uptake between early and late examinations for the identification of HGG was 81 % (sensitivity 83 %; specificity 75 %; cutoff - 8 %; p < 0.001), and 83 % for curve pattern analysis (sensitivity 88 %; specificity 75 %; p < 0.001). Dual-time-point imaging of 18 F-FET uptake in gliomas achieves diagnostic accuracy for tumour grading that is similar to the more time-consuming dynamic data acquisition protocol. (orig.)

Dosimetric estimation of O-(3-18F-fluoropropyl)-L-tyrosine in human based on mice biodistribution data

International Nuclear Information System (INIS)

Tang Ganghua; Wang Mingfang; Luo Lei; Gan Manquan; Tang Xiaolan

2002-01-01

Objective: To estimate the radiation absorbed doses in humans due to intravenous administration of O-(3- 18 F-fluoropropyl)-L-tyrosine (FPT) based on mice biodistribution data and appraise the security of FPT in humans. Methods: FPT was injected into mice through a tail vein. At 10, 30, 60, 120 and 180 min after injection, the mice were killed by cervical fracture and biodistribution in mice were determined. Human dosimetric estimation was performed from the biodistribution of FPT in mice and the standard MIRD method using fractional radioactivity-time curves for humans. Results: The bone in human was the organ receiving highest dose of 4.29 x 10 -3 mGy/MBq, the brain received lowest dose of 1.57 x 10 -3 mGy/MBq, and other organs received doses between 1.8 x 10 -3 and 2.4 x 10 -3 mGy/MBq. The effective dose was estimated to be 9.15 x 10 -3 mSv/MBq. These results were comparable to values reported by foreign authors on the radiation dosimetry of O-(2- 18 F-fluoroethyl)-L-tyrosine. Conclusion: Human dosimetric estimation can be performed based on mice biodistribution data. The study provides an important data for clinical safety of FPT

Reduction of intergranular exchange coupling and grain size for high Ku CoPt-based granular media: Metal-oxide buffer layer and multiple oxide boundary materials

Science.gov (United States)

Tham, Kim Kong; Kushibiki, Ryosuke; Kamada, Tomonari; Hinata, Shintaro; Saito, Shin

2018-05-01

Investigation of magnetic properties and microstructure of granular media with various multiple oxides as the grain boundary material is reported. Saturation magnetization (Ms), uniaxial magnetocrystalline anisotropy (Ku), and magnetic grain diameter (GD) of the granular media show linear correlation with volume weighted average for melting point (Tm) of each oxides (Tmave). Ku of magnetic grains (Kugrain) shows a trade-off relation with GD that it is a big challenge to satisfy both high Kugrain and small GD by only controlling Tmave. To obtain a granular medium with appropriate Kugrain, GD, and low degree of intergranular exchange coupling, the combination of Tmave control of grain boundary material by mixing oxides and employment of a buffer layer are required. Here the degree of intergranular exchange coupling is estimated from the slope of M-H loop at around coercivity (α). By applying this technique, a typical granular medium with Kugrain of 1.0×107 erg/cm3, GD of 5.1 nm, and α of 1.2 is realized.

A high efficiency Ku-band radial line relativistic klystron amplifier

Energy Technology Data Exchange (ETDEWEB)

Dang, Fangchao; Zhang, Xiaoping, E-mail: zhangxiaoping@nudt.edu.cn; Zhong, Huihuang; Zhang, Jun; Ju, Jinchuan [College of Optoelectronic Science and Engineering, National University of Defense Technology, Changsha 410073 (China)

2016-07-15

To achieve the gigawatt-level microwave amplification output at Ku-band, a radial-line relativistic klystron amplifier is proposed and investigated in this paper. Different from the annular electron beam in conventional axial relativistic klystron amplifiers, a radial-radiated electron beam is employed in this proposed klystron. Owing to its radially spreading speciality, the electron density and space charge effect are markedly weakened during the propagation in the radial line drift tube. Additionally, the power capacity, especially in the output cavity, is enhanced significantly because of its large volume, which is profitable for the long pulse operation. Particle-in-cell simulation results demonstrate that a high power microwave with the power of 3 GW and the frequency of 14.25 GHz is generated with a 500 kV, 12 kA electron beam excitation and the 30 kW radio-frequency signal injection. The power conversion efficiency is 50%, and the gain is about 50 dB. Meanwhile, there is insignificant electron beam self-excitation in the proposed structure by the adoption of two transverse electromagnetic reflectors. The relative phase difference between the injected signals and output microwaves keeps stable after the amplifier saturates.

Effects of surface roughness on sea ice freeboard retrieval with an Airborne Ku-Band SAR radar altimeter

DEFF Research Database (Denmark)

Hendricks, Stefan; Stenseng, Lars; Helm, Veit

2010-01-01

to investigate sea ice volume changes on an Arctic wide scale. Freeboard retrieval requires precise radar range measurements to the ice surface, therefore we investigate the penetration of the Ku-Band radar waves into the overlying snow cover as well as the effects of sub-footprint-scale surface roughness using...... airborne radar and laser altimeters. We find regional variable penetration of the radar signal at late spring conditions, where the difference of the radar and the reference laser range measurement never agrees with the expected snow thickness. In addition, a rough surface can lead to biases...

Anti-L. donovani activity in macrophage/amastigote model of palmarumycin CP18 and its large scale production.

Science.gov (United States)

Ortega, Humberto E; Teixeira, Eliane de Morais; Rabello, Ana; Higginbotham, Sarah; Cubilla-Ríos, Luis

2014-01-01

Palmarumycin CP18, isolated from an extract of the fermentation broth and mycelium of the Panamanian endophytic fungus Edenia sp., was previously reported with strong and specific activity against Leishmania donovani. Here we report that when the same strain was cultured on different solid media--Harrold Agar, Leonian Agar, Potato dextrose Agar (PDA), Corn Meal Agar, Honey Peptone Agar, and eight vegetables (V8) Agar--in order to determine the optimal conditions for isolation of palmarumycin CP18, no signal for this compound was observed in any of the 1H NMR spectra of fractions obtained from these extracts. However, one extract, prepared from the fungal culture in PDA contained significant amounts of CJ-12,372, a possible biosynthetic precursor of palmarumycin CP18. Edenia sp. was cultivated on a large scale on PDA and CJ-12,372 was converted to palmarumycin CP18 by oxidation of its p-hydroquinone moiety with DDQ in dioxane. Palmarumycin CP18 showed anti-leishmanial activity against L. donovani in a macrophage/amastigote model, with IC50 values of 23.5 microM.

Mātes audzināšanas stila saistība ar emocionālā intelekta (EI) līmeni 8-12 gadu veciem bērniem

OpenAIRE

Grjunberga, Inese

2014-01-01

Mūsdienās arvien biežāk var sastapties ar bērniem kuriem ir grūtības adaptēties, mācīties. Bērniem bieži neveidojas labas attiecības ar vienaudžiem, draudzība. Iepriekšējos pētījumos noskaidrots, ka bērna emocionālā attīstība ir saistīta arī ar vecāku audzināšanu.Pētījuma mērķis bija noskaidrot vai mātes audzināšanas stils saistīts ar bērnu emocionālā intelekta līmeni. Pētījumā peidalījās bērni (N=100) no divām Latvijas skolām. Dalībnieki vecumā no 8 – 12 gadiem (M=11. 00, SD=1. 38). No kuri...

Deficient Pms2, ERCC1, Ku86, CcOI in field defects during progression to colon cancer.

Science.gov (United States)

Nguyen, Huy; Loustaunau, Cristy; Facista, Alexander; Ramsey, Lois; Hassounah, Nadia; Taylor, Hilary; Krouse, Robert; Payne, Claire M; Tsikitis, V Liana; Goldschmid, Steve; Banerjee, Bhaskar; Perini, Rafael F; Bernstein, Carol

2010-07-28

In carcinogenesis, the "field defect" is recognized clinically because of the high propensity of survivors of certain cancers to develop other malignancies of the same tissue type, often in a nearby location. Such field defects have been indicated in colon cancer. The molecular abnormalities that are responsible for a field defect in the colon should be detectable at high frequency in the histologically normal tissue surrounding a colonic adenocarcinoma or surrounding an adenoma with advanced neoplasia (well on the way to a colon cancer), but at low frequency in the colonic mucosa from patients without colonic neoplasia. Using immunohistochemistry, entire crypts within 10 cm on each side of colonic adenocarcinomas or advanced colonic neoplasias were found to be frequently reduced or absent in expression for two DNA repair proteins, Pms2 and/or ERCC1. Pms2 is a dual role protein, active in DNA mismatch repair as well as needed in apoptosis of cells with excess DNA damage. ERCC1 is active in DNA nucleotide excision repair. The reduced or absent expression of both ERCC1 and Pms2 would create cells with both increased ability to survive (apoptosis resistance) and increased level of mutability. The reduced or absent expression of both ERCC1 and Pms2 is likely an early step in progression to colon cancer. DNA repair gene Ku86 (active in DNA non-homologous end joining) and Cytochrome c Oxidase Subunit I (involved in apoptosis) had each been reported to be decreased in expression in mucosal areas close to colon cancers. However, immunohistochemical evaluation of their levels of expression showed only low to modest frequencies of crypts to be deficient in their expression in a field defect surrounding colon cancer or surrounding advanced colonic neoplasia. We show, here, our method of evaluation of crypts for expression of ERCC1, Pms2, Ku86 and CcOI. We show that frequency of entire crypts deficient for Pms2 and ERCC1 is often as great as 70% to 95% in 20 cm long areas

Manipulation of [C-11]-5-hydroxytryptophan and 6-[F-18]fluoro-3,4-dihydroxy-L-phenylalanine accumulation in neuroendocrine tumor cells

NARCIS (Netherlands)

Neels, Oliver C.; Koopmans, Klaas P.; Jager, Pieter L.; Vercauteren, Laya; van Waarde, Aren; Doorduin, Janine; Timmer-Bosscha, Hetty; Brouwers, Adrienne H.; de Vries, Elisabeth G. E.; Dierckx, Rudi A. J. O.; Kema, Ido P.; Elsinga, Philip H.

2008-01-01

[C-11]-5-Hydroxytryptophan ([C-11]HTP) and 6-[F-18]fluoro-3,4-dihydroxy-L-phenylalanine [F-18]FDOPA) are used to image neuroendocrine tumors with positron emission tomography. The precise mechanism by which these tracers accumulate in tumor cells is unknown. We aimed to study tracer uptake via large

The added value of [{sup 18}F]fluoro-L-DOPA PET in the diagnosis of hyperinsulinism of infancy: a retrospective study involving 49 children

Energy Technology Data Exchange (ETDEWEB)

Ribeiro, Maria-Joao; Bourgeois, Sandrine; Delzescaux, Thierry [Frederic Joliot Hospital, Biomedical Imaging Institute, Life Sciences Division, CEA, Orsay (France); Boddaert, Nathalie; Brunelle, Francis [Necker-Enfants Malades Hospital, AP-HP, Department of Radiology, Paris (France); Bellanne-Chantelot, Christine [Saint-Antoine Hospital, AP-HP, Department of Cytogenetics, Paris (France); Valayannopoulos, Vassili; Lonlay, Pascale de [Necker-Enfants Malades Hospital, AP-HP, Department of Pediatrics, Paris (France); Jaubert, Francis [Necker-Enfants Malades Hospital, AP-HP, Department of Pathology, Paris (France); Nihoul-Fekete, Claire [Necker-Enfants Malades Hospital, AP-HP, Department of Surgery, Paris (France)

2007-12-15

Neuroendocrine diseases are a heterogeneous group of entities with the ability to take up amine precursors, such as L-DOPA, and convert them into biogenic amines, such as dopamine. Congenital hyperinsulinism of infancy (HI) is a neuroendocrine disease secondary to either focal adenomatous hyperplasia or a diffuse abnormal pancreatic insulin secretion. While focal hyperinsulinism may be reversed by selective surgical resection, diffuse forms require near-total pancreatectomy when resistant to medical treatment. Here, we report the diagnostic value of PET with [{sup 18}F]fluoro-L-DOPA in distinguishing focal from diffuse HI. Forty-nine children were studied with [{sup 18}F]fluoro-L-DOPA. A thoraco-abdominal scan was acquired 45-65 min after the injection of 4.2 {+-} 1.0 MBq/kg of [{sup 18}F]fluoro-L-DOPA. Additionally, 12 of the 49 children were submitted to pancreatic venous catheterisation for blood samples (PVS) and 31 were also investigated using MRI. We identified abnormal focal pancreatic uptake of [{sup 18}F]fluoro-L-DOPA in 15 children, whereas diffuse radiotracer uptake was observed in the pancreatic area in the other 34 patients. In children studied with both PET and PVS, the results were concordant in 11/12 cases. All patients with focal radiotracer uptake and nine of the patients with diffuse pancreatic radiotracer accumulation, unresponsive to medical treatment, were submitted to surgery. In 21 of these 24 patients, the histopathological results confirmed the PET findings. In focal forms, selective surgery was followed by clinical remission without carbohydrate intolerance. These data demonstrate that PET with [{sup 18}F]fluoro-L-DOPA is an accurate non-invasive technique allowing differential diagnosis between focal and diffuse forms of HI. (orig.)

Translucency and masking ability of various composite resins at different thicknesses.

Science.gov (United States)

Darabi, Farideh; Radafshar, Golpar; Tavangar, Maryam; Davaloo, Reza; Khosravian, Aref; Mirfarhadi, Nastaran

2014-09-01

Optical properties of the composite resins, concerning their translucency and thickness, are affected by discolored tooth structure or inherent darkness of the oral cavity. This study aimed to compare the translucency parameter (TP) of five different composite resins in different thicknesses and to evaluate their masking ability in black backgrounds. Five brands of composite resins; Gradia (GC) and Crystalline (Confi-dental) in opaque A2 (OA2), Vit-l-escence (Ultradent) in opaque snow (OS), Herculite XRV (Kerr) and Opallis (FGM) in dentin A2 (DA2) shades were selected to enroll the study. Color coordinates of each composite were determined at 0.5, 1, and 1.5 mm thicknesses on a white backing, the backing of material itself and a black backing were calculated by using a spectrophotometer to evaluate the translucency parameter (TP) of the study materials. The masking ability was also calculated from the specimens on the material itself and on black backing. The values under 2 were estimated as imperceptible. One-way ANOVA, T-test and Tukey HSD were employed for statistical analysis. The masking ability values, recorded for the 1.5 mm-thick specimens, were in the range of imperceptible except for the Herculite. There was no difference in TP values of the materials at 1.5 mm thickness. Opaque snow shade of Vit-l-escence and opaque A2 shade of Gradia showed lower TP values in comparison with the other 1 and 0.5 mm-thick materials and this difference was statistically significant (pcomposite resins could not mask the black background color.

Diaspididae (Hemiptera, Coccoidea in sori of two fern species

Directory of Open Access Journals (Sweden)

Marcelo Santos

2015-12-01

Duas Espécies de Cochonilhas (Hemiptera: Diaspididae Associadas com Soros de Samambaias Resumo. A presente comunicação relata a presença de duas espécies de cochonilhas Hemiberlesia palmae (Cockerell e Pinnaspis strachani (Cooley (Coccoidea, Diaspididae, associadas respectivamente com Asplenium serratum L. (Aspleniaceae e Niphidium crassifolium (L. Lellinger (Polypodiaceae. É o primeiro registro de uma samambaia como planta hospedeira de Hemiberlesia palmae.  Nas duas espécies de samambaias, os diaspidídeos encontravam-se concentrados principalmente ao redor dos soros.

The translocator protein radioligand 18F-DPA-714 monitors antitumor effect of erufosine in a rat 9L intracranial glioma model

International Nuclear Information System (INIS)

Awde, Ali R.; Boisgard, Raphael; Theze, Benoit; Dubois, Albertine; Zheng, Jinzi; Winkeler, Alexandra; Dolle, Frederic; Jacobs, Andreas H.; Tavitian, Bertrand

2013-01-01

On the one hand, the translocator protein (TSPO) radioligand N,N-diethyl-2-(2-(4-(2- 18 F-fluoroethoxy)phenyl)-5,7-dimethylpyrazolo[1,5-a] pyrimidin-3-yl)acetamide ( 18 F-DPA-714) has been suggested to serve as an alternative radiotracer to image human glioma, and on the other hand the alkyl-phosphocholine erufosine (ErPC3) has been reported to induce apoptosis in otherwise highly apoptosis resistant glioma cell lines. The induction of apoptosis by ErPC3 requires TSPO, a mitochondrial membrane protein highly expressed in malignant gliomas. In this preclinical study, we monitored the effect of ErPC3 treatment in vivo using 18 F-DPA-714 PET. Methods: In vitro studies investigated the antitumor effect of ErPC3 in 9L rat gliosarcoma cells. In vivo, glioma-bearing rats were imaged with 18 F-DPA-714 for the time of treatment. Results: A significant decrease in 9L cell proliferation and viability and a significant increase in apoptosis and caspase-3 activation were demonstrated on ErPC3 treatment in cell culture. In the rat model, ErPC3 administration resulted in significant changes in 18 F-DPA-714 tumor uptake over the course of the treatment. Immunohistochemistry revealed reduced tumor volume and increased cell death in ErPC3-treated animals accompanied by infiltration of the tumor core by CD11b-positive micro-glia/macrophages and glial fibrillary acidic protein-positive astrocytes. Conclusion: Our findings demonstrate a potent antitumor effect of ErPC3 in vitro, in vivo, and ex vivo. PET imaging of TSPO expression using 18 F-DPA-714 allows effective monitoring and quantification of disease progression and response to ErPC3 therapy in intracranial 9L gliomas. (authors)

Measurement of striatal dopamine metabolism with 6-[18F]-fluoro-L-dopa and PET

International Nuclear Information System (INIS)

Kuwabara, Y.; Otsuka, M.; Ichiya, Y.; Yoshikai, T.; Fukumura, T.; Masuda, K.; Kato, M.; Taniwaki, T.

1992-01-01

Striatal dopamine metabolism was studied with 6-[ 18 F]-fluoro-L-dopa ( 18 F-DOPA) and PET. The subjects were normal controls, and patients with Parkinson's disease (PD), parkinsonism, multiple system atrophy (MSA), progressive supranuclear palsy (PSP), Alzheimer's disease (AD), Huntington's disease (HD) and other cerebral disorders. Cerebral glucose metabolism (CMRGlc) was also measured in these patients. Striatal dopamine metabolism was evaluated by the relative striatal uptake of 18 F-DOPA referring cerebellum (S/C ratio). In normal controls, the S/C ratio was 2.82 ± 0.32 (n = 6, mean ± SD) at 120 min after injection of 18 F-DOPA. The S/C ratio was low in patients with PD, parkinsonism, MSA and PSP compared to the normal controls and thus coincident with the symptoms of parkinsonism due to decrease in striatal dopamine concentration. The decrease in the striatal CMRGlc was also observed in patients with parkinsonism and PSP, and it was preserved in patients with PD, thus representing that more neurons were damaged in patients with parkinsonism and PSP than in patients with PD. A patient with AD having symptoms of parkinsonism also showed a decrease in S/C ratio. In a patient with HD, the striatal CMRGlc sharply decreased, but the S/C ratio was normal. The measurements of striatal dopamine and glucose metabolism with PET may be useful for studying the pathophysiological mechanism in patients with cerebral disorders. (author)

Extreme Anemia (Hemoglobin 1.8 g/dL Secondary to Abnormal Uterine Bleeding

Directory of Open Access Journals (Sweden)

Ketaki Panse

2017-01-01

Full Text Available We present the case of a 39-year-old G5P5 woman who presented to the emergency department with complaints of shortness of breath, lightheadedness, and excessive uterine bleeding for 14 days, with a heart rate of 123 and a blood pressure of 137/65. Menses had been heavy for several months. A hemoglobin of 1.8 g/dL was discovered. An ultrasound revealed an 11.8 cm fibroid uterus, and the patient was transfused with 6 units of blood and placed on oral contraceptive pills.

(S)-4-(3-18F-fluoropropyl)-L-glutamic acid: an 18F-labeled tumor-specific probe for PET/CT imaging--dosimetry.

Science.gov (United States)

Smolarz, Kamilla; Krause, Bernd Joachim; Graner, Frank-Philipp; Wagner, Franziska Martina; Hultsch, Christina; Bacher-Stier, Claudia; Sparks, Richard B; Ramsay, Susan; Fels, Lüder M; Dinkelborg, Ludger M; Schwaiger, Markus

2013-06-01

The glutamic acid derivative (S)-4-(3-(18)F-Fluoropropyl)-l-glutamic acid ((18)F-FSPG, alias BAY 94-9392), a new PET tracer for the detection of malignant diseases, displayed promising results in non-small cell lung cancer patients. The aim of this study was to provide dosimetry estimates for (18)F-FSPG based on human whole-body PET/CT measurements. (18)F-FSPG was prepared by a fully automated 2-step procedure and purified by a solid-phase extraction method. PET/CT scans were obtained for 5 healthy volunteers (mean age, 59 y; age range, 51-64 y; 2 men, 3 women). Human subjects were imaged for up to 240 min using a PET/CT scanner after intravenous injection of 299 ± 22.5 MBq of (18)F-FSPG. Image quantification, time-activity data modeling, estimation of normalized number of disintegrations, and production of dosimetry estimates were performed using the RADAR (RAdiation Dose Assessment Resource) method for internal dosimetry and in general concordance with the methodology and principles as presented in the MIRD 16 document. Because of the renal excretion of the tracer, the absorbed dose was highest in the urinary bladder wall and kidneys, followed by the pancreas and uterus. The individual organ doses (mSv/MBq) were 0.40 ± 0.058 for the urinary bladder wall, 0.11 ± 0.011 for the kidneys, 0.077 ± 0.020 for the pancreas, and 0.030 ± 0.0034 for the uterus. The calculated effective dose was 0.032 ± 0.0034 mSv/MBq. Absorbed dose to the bladder and the effective dose can be reduced significantly by frequent bladder-voiding intervals. For a 0.75-h voiding interval, the bladder dose was reduced to 0.10 ± 0.012 mSv/MBq, and the effective dose was reduced to 0.015 ± 0.0010 mSv/MBq. On the basis of the distribution and biokinetic data, the determined radiation dose for (18)F-FSPG was calculated to be 9.5 ± 1.0 mSv at a patient dose of 300 MBq, which is of similar magnitude to that of (18)F-FDG (5.7 mSv). The effective dose can be reduced to 4.5 ± 0.30 mSv (at 300 MBq

Reklāma kā sociālā mārketinga elements un tās efektivitāte: CSDD sociālā TV reklāma "Orgānu donori"

OpenAIRE

Priedīte, Unda

2008-01-01

Bakalaura darba tēma ir „ Reklāma kā sociālā mārketinga elements un tās efektivitāte: CSDD sociālā TV reklāma „ Orgānu donori ””. Darbā izvirzītā hipotēze: sociālā TV reklāma „Orgānu donori” kā sociālā mārketinga elements ir bijusi efektīva un tā attaisno vizuālo un tekstuālo risinājumu izvēli, jo spēcīgas emocijas ir viens no efektīvākajiem veidiem, kā sociālo problēmu kontekstā mainīt cilvēku attieksmi un rīcību. Pēc paveiktās teorētiskās informācijas apstrādes un pētījuma rezultātu ana...

Sejas ādas kopšanas līdzekļi pusaudžu vecumā

OpenAIRE

Škute, Solvita

2014-01-01

Darbā tiek apskatīti pusaudži, kuri lieto sejas ādas kopšanas līdzekļus, lai novērstu sejas ādas problēmas. Tiek izklāstīts par sejas ādas slimībām, kā pareizi rīkoties un, kas jāievēro šādiem pacientiem. Uzmanība likta uz pacientiem, kuriem jau ir sejas ādas problēmas ilgāku laiku. Bakalaura darba tēma – "Sejas ādas kopšanas līdzekļi pusaudžu vecumā". Tēmas aktualitāti nosaka sejas ādas kopšanas līdzekļu efektivitāte. Darba mērķis ir noskaidrot jauniešu sejas ādas kopšanas līdzekļu pie...

Resistance to Sri Lankan Cassava Mosaic Virus (SLCMV) in Genetically Engineered Cassava cv. KU50 through RNA Silencing

KAUST Repository

Ntui, Valentine Otang

2015-04-22

Cassava ranks fifth among the starch producing crops of the world, its annual bioethanol yield is higher than for any other crop. Cassava cultivar KU50, the most widely grown cultivar for non-food purposes is susceptible to Sri Lankan cassava mosaic virus (SLCMV). The objective of this work was to engineer resistance to SLCMV by RNA interference (RNAi) in order to increase biomass yield, an important aspect for bioethanol production. Here, we produced transgenic KU50 lines expressing dsRNA homologous to the region between the AV2 and AV1 of DNA A of SLCMV. High level expression of dsRNA of SLCMV did not induce any growth abnormality in the transgenic plants. Transgenic lines displayed high levels of resistance to SLCMV compared to the wild-type plants and no virus load could be detected in uninoculated new leaves of the infected resistant lines after PCR amplification and RT-PCR analysis. The agronomic performance of the transgenic lines was unimpaired after inoculation with the virus as the plants presented similar growth when compared to the mock inoculated control plants and revealed no apparent reduction in the amount and weight of tubers produced. We show that the resistance is correlated with post-transcriptional gene silencing because of the production of transgene specific siRNA. The results demonstrate that transgenic lines exhibited high levels of resistance to SLCMV. This resistance coupled with the desirable yield components in the transgenic lines makes them better candidates for exploitation in the production of biomass as well as bioethanol.

Resistance to Sri Lankan Cassava Mosaic Virus (SLCMV) in Genetically Engineered Cassava cv. KU50 through RNA Silencing

KAUST Repository

Ntui, Valentine Otang; Kong, Kynet; Khan, Raham Sher; Igawa, Tomoko; Janavi, Gnanaguru Janaky; Rabindran, Ramalingam; Nakamura, Ikuo; Mii, Masahiro

2015-01-01

Cassava ranks fifth among the starch producing crops of the world, its annual bioethanol yield is higher than for any other crop. Cassava cultivar KU50, the most widely grown cultivar for non-food purposes is susceptible to Sri Lankan cassava mosaic virus (SLCMV). The objective of this work was to engineer resistance to SLCMV by RNA interference (RNAi) in order to increase biomass yield, an important aspect for bioethanol production. Here, we produced transgenic KU50 lines expressing dsRNA homologous to the region between the AV2 and AV1 of DNA A of SLCMV. High level expression of dsRNA of SLCMV did not induce any growth abnormality in the transgenic plants. Transgenic lines displayed high levels of resistance to SLCMV compared to the wild-type plants and no virus load could be detected in uninoculated new leaves of the infected resistant lines after PCR amplification and RT-PCR analysis. The agronomic performance of the transgenic lines was unimpaired after inoculation with the virus as the plants presented similar growth when compared to the mock inoculated control plants and revealed no apparent reduction in the amount and weight of tubers produced. We show that the resistance is correlated with post-transcriptional gene silencing because of the production of transgene specific siRNA. The results demonstrate that transgenic lines exhibited high levels of resistance to SLCMV. This resistance coupled with the desirable yield components in the transgenic lines makes them better candidates for exploitation in the production of biomass as well as bioethanol.

Chemical consequences resulting from multi-millicurie preparation of 6-[18F]-fluoro-6-deoxy-L-ascorbic acid

International Nuclear Information System (INIS)

Kothari, P.J.; Finn, R.D.; Bornmann, W.G.; Agus, D.B.; Vera, J.C.; Larson, S.M.

1997-01-01

Ascorbic acid is required for human physiology and is particularly important in maintaining normal connective tissue and host defense. Our interest in this carboxylic acid stems from its similarity in transport with glucose in human cells. In order to investigate these phenomena, we report a refined synthesis of 6-[ 18 F]-fluoro-6-deoxy-L-ascorbic acid ( 18 F-FAA) via nucleophilic displacement of the cyclic sulfate with Kryptofix 2.2.2/K 18 F complex which results in multi-millicurie quantities of high specific activity product. The trace carrier-added synthesis has resulted in a decay corrected radiochemical yield of 31.6±3.4% with a specific activity approaching 180 mCi/μmol. Our preliminary experience with the assessment of the chemical stability of both the radiolabelled and stable product is also presented. (orig.)

Diagnostic usefulness of {sup 18}F-FAMT PET and L-type amino acid transporter 1 (LAT1) expression in oral squamous cell carcinoma

Energy Technology Data Exchange (ETDEWEB)

Nobusawa, Aiko [Gunma University Graduate School of Medicine, Department of Stomatology and Maxillofacial Surgery, Maebashi, Gunma (Japan); Gunma University Graduate School of Medicine, Department of Diagnostic Pathology, Maebashi, Gunma (Japan); Kim, Mai [Gunma University Graduate School of Medicine, Department of Stomatology and Maxillofacial Surgery, Maebashi, Gunma (Japan); Gunma University Graduate School of Medicine, Department of Diagnostic Radiology and Nuclear Medicine, Maebashi, Gunma (Japan); Kaira, Kyoichi [Gunma University Graduate School of Medicine, Department of Diagnostic Pathology, Maebashi, Gunma (Japan); Gunma University Hospital, Oncology Center, Maebashi, Gunma (Japan); Miyashita, Go; Negishi, Akihide; Yokoo, Satoshi [Gunma University Graduate School of Medicine, Department of Stomatology and Maxillofacial Surgery, Maebashi, Gunma (Japan); Oriuchi, Noboru; Higuchi, Tetsuya; Tsushima, Yoshito [Gunma University Graduate School of Medicine, Department of Diagnostic Radiology and Nuclear Medicine, Maebashi, Gunma (Japan); Kanai, Yoshikatsu [Osaka University, Division of Bio-system Pharmacology, Graduate School of Medicine, Osaka (Japan); Oyama, Tetsunari [Gunma University Graduate School of Medicine, Department of Diagnostic Pathology, Maebashi, Gunma (Japan)

2013-10-15

l-[3-{sup 18}F]-{alpha}-Methyltyrosine ({sup 18}F-FAMT) was developed as an amino acid tracer for PET imaging to provide better specificity than 2-[{sup 18}F]fluoro-2-deoxy-d-glucose ({sup 18}F-FDG) PET for cancer diagnosis. We investigated the diagnostic usefulness of {sup 18}F-FAMT in oral squamous cell carcinoma (OSCC). The correlation between tumour uptake of {sup 18}F-FAMT and L-type amino acid transporter 1 (LAT1) expression was determined. The study group comprised 68 OSCC patients who underwent both {sup 18}F-FAMT and {sup 18}F-FDG PET. Resected tumour sections were stained by immunohistochemistry for LAT1, CD98 and Ki-67, and microvessel density was determined in terms of CD34 and p53 expression. The sensitivity of primary tumour detection by {sup 18}F-FAMT and {sup 18}F-FDG PET was 98 % and 100 %, respectively. The sensitivity, specificity and accuracy of {sup 18}F-FAMT PET for detecting malignant lymph nodes were 68 %, 99 % and 97 %, respectively, and equivalent values for {sup 18}F-FDG PET were 84 %, 94 % and 94 %, respectively. The specificity and accuracy of {sup 18}F-FAMT were significantly higher than those of {sup 18}F-FDG. The uptake of {sup 18}F-FAMT was significantly correlated with LAT1 expression, cell proliferation and advanced stage. The expression of LAT1 in OSCC cells was closely correlated with CD98 levels, cell proliferation and angiogenesis. {sup 18}F-FAMT PET showed higher specificity for detecting malignant lesions than {sup 18}F-FDG PET. The uptake of {sup 18}F-FAMT by OSCC cells can be determined by the presence of LAT1 expression and tumour cell proliferation. (orig.)

Destruction of gel sulfonated cation-exchangers of the KU-2 type under the influence of hydrogen peroxide

Energy Technology Data Exchange (ETDEWEB)

Roginskaya, B.S.; Zavadovskaya, A.S.; Znamenskii, Yu.P.; Paskhina, N.A.; Dobrova, E.I.

1988-10-20

The purpose of this work was to study the mechanism of interaction of Soviet sulfonated cation-exchangers of the KU-2 type with hydrogen peroxide. It is shown that under the influence of hydrogen peroxide sulfonated cation-exchangers begin, after a certain induction period, to lose capacity and to release destruction products into water; the length of the induction period increases with the degree of cross-linking. In a given time of contact between the resin and the solution the degree of destruction falls with increase of cross-linking. The principal product of destruction of sulfonated cation-exchangers is an aromatic sulfonic acid containing oxidized groups in the side chains.

Reduction of intergranular exchange coupling and grain size for high Ku CoPt-based granular media: Metal-oxide buffer layer and multiple oxide boundary materials

Directory of Open Access Journals (Sweden)

Kim Kong Tham

2018-05-01

Full Text Available Investigation of magnetic properties and microstructure of granular media with various multiple oxides as the grain boundary material is reported. Saturation magnetization (Ms, uniaxial magnetocrystalline anisotropy (Ku, and magnetic grain diameter (GD of the granular media show linear correlation with volume weighted average for melting point (Tm of each oxides (Tmave. Ku of magnetic grains (Kugrain shows a trade-off relation with GD that it is a big challenge to satisfy both high Kugrain and small GD by only controlling Tmave. To obtain a granular medium with appropriate Kugrain, GD, and low degree of intergranular exchange coupling, the combination of Tmave control of grain boundary material by mixing oxides and employment of a buffer layer are required. Here the degree of intergranular exchange coupling is estimated from the slope of M-H loop at around coercivity (α. By applying this technique, a typical granular medium with Kugrain of 1.0×107 erg/cm3, GD of 5.1 nm, and α of 1.2 is realized.

Teplovodní výměník pro krbovou vložku

OpenAIRE

Kněžínek, Petr

2012-01-01

Diplomová práce je zaměřena na problematiku zapojení krbových kamen a krbových vložek do teplovodních vytápěcích systémů. Práce obsahuje stručný popis krbů a otopných soustav. Konkrétně se zabývá návrhem teplovodního výměníku pro krbová kamna. Poslední část práce je věnována experimentálnímu ověření provozních parametrů a vyhodnocení získaných výsledků. The diploma thesis is focused on problems connecting of fireplace with water heating systems. The thesis comprises concise description of ...

A technical writing programme implemented in a first-year engineering course at KU Leuven

Science.gov (United States)

Heylen, Christel; Vander Sloten, Jos

2013-12-01

Technical communication and technical writing are important skills for the daily work-life of every engineer. In the first-year engineering programme at KU Leuven, a technical writing programme is implemented within the project-based course 'Problem Solving and Engineering Design'. This paper describes a case study for implementing a writing programme based on active learning methods and situated learning in large classes. The programme consists of subsequent cycles of instructions, learning by doing and reflection on received feedback. In addition, a peer-review assignment, together with an interactive lecture using clicking devices, is incorporated within the assignments of the second semester. A checklist of desired writing abilities makes it easier to grade the large number of papers. Furthermore, this ensures that all staff involved in the evaluation process uses the same criteria to grade and for providing feedback.

8 – 11 gadus vecu bērnu pašcieņas saistība ar vecāku audzināšanas stilu un tehnoferenci

OpenAIRE

Ērmane, Linda

2017-01-01

Ir izvirzīts pētījuma mērķis teorētiski un praktiski izpētīt 8 – 11 gadus vecu bērnu pašcieņas saistību ar vecāku audzināšanas stilu un tehnoferenci. Pētījumā ir viena hipotēze par to, ka pastāv saistība starp vecāku audzināšanas stilu, bērnu pašcieņu un tehoferenci. Pētījuma izlasi veido 15 bērni (M = 9,6 gadi; SD = 1,12; 8 meitenes un 7 zēni) un 30 vecāki (M = 36,8 gadi; SD = 5,74; 15 vīrieši un 15 sievietes). Ir izmantoti 3 instrumenti: Audzināšanas pieeju aptauja, Tehnoloģijas ierīču ieja...

Priming effects of leaves of Laurus nobilis L. and 1,8-cineole on carbon mineralization

Directory of Open Access Journals (Sweden)

Burak Kocak

2016-03-01

Full Text Available Plant secondary compounds can have stimulating effect on C cycling and change its rate in soils. We examined how leaves of bay laurel (Laurus nobilis L.; Lauraceae and 1,8-cineole (CIN, one of its constituents, affect soil C mineralization and its rate. Leaves and soil samples of bay laurel were taken from Cukurova University Campus (Adana, Turkey growing naturally under Mediterranean climate conditions. Leaves and CIN were considered as the two forms of organic C sources. After determining the level of 1,8-cineole in leaves by gas chromatography-mass spectrometry, soils were mixed with powdered leaves and 1,8-cineole based on their C contents at same and half doses of soil organic C level. Carbon mineralization of all soils was determined over 54 d (28 °C, 80% field capacity. While 1,8-cineole was found as a major constituent of leaves (65% of essential oil, all doses of leaves and CIN increased soil microbial activity. There were significant differences for C mineralization rate between control and all applications (P < 0.05. High C levels of all treatments decreased C mineralization rate compared to control soils. In summary, all treatments stimulated C mineralization and it is possible to conclude that soil microorganisms adapted to use CIN as an energy source.

Spanish cross-cultural adaptation and psychometric properties of the Schizophrenia Quality of Life short-version questionnaire (SQoL18) in 3 middle-income countries: Bolivia, Chile and Peru.

Science.gov (United States)

Caqueo-Urízar, Alejandra; Boyer, Laurent; Boucekine, Mohamed; Auquier, Pascal

2014-10-01

The aim of this study was to adapt the Schizophrenia - Quality of Life short-version questionnaire (SQoL18) for use in three middle-income countries in Latin America and to evaluate the factor structure, reliability, and external validity of this questionnaire. The SQoL18 was translated into Spanish using a well-validated forward-backward process. We evaluated the psychometric properties of the SQoL18 in a sample of 253 patients with schizophrenia attending outpatient mental health services in three Latin American countries. For participants in each country (Bolivia, N=83; Chile, N=85; Peru, N=85), psychometric properties were compared to those reported from the reference population (507 patients with schizophrenia) assessed in the validation study. In addition, differential item functioning (DIF) analyses were performed to see whether all items behave in the same way in each country. Factor analysis performed in the 3 countries showed that the questionnaire's structure adequately matched the initial structure of the SQoL18. The unidimensionality of the dimensions was preserved, and the internal/external validity indices were close to those of the reference population. However, one dimension of the SQoL18 (resilience) presented some unsatisfactory properties including low Cronbach's alpha coefficients, one INFIT value higher than 1.2, and one item showing DIF between the 3 countries. These results demonstrate the satisfactory acceptability and psychometric properties of the SQoL18, suggesting the relevance of this questionnaire among patients with schizophrenia in these 3 Latin American countries. Copyright © 2014 Elsevier B.V. All rights reserved.

Multitude scaling laws in axisymmetric turbulent wake

Science.gov (United States)

Layek, G. C.; Sunita

2018-03-01

We establish theoretically multitude scaling laws of a self-similar (statistical) axisymmetric turbulent wake. At infinite Reynolds number limit, the flow evolves as general power law and a new exponential law of streamwise distance, consistent with the criterion of equilibrium similarity hypothesis. We found power law scalings for components of the homogeneous dissipation rate (ɛ) obeying the non-Richardson-Kolmogorov cascade as ɛu˜ku3 /2/(l R elm ) , ɛv˜kv3 /2/l , kv˜ku/R el2 m, 0 stress, l is the local length scale, and Rel is the Reynolds number. The Richardson-Kolmogorov cascade corresponds to m = 0. For m ≈ 1, the power law agrees with non-equilibrium scaling laws observed in recent experiments of the axisymmetric wake. On the contrary, the exponential scaling law follows the above dissipation law with different regions of existence for power index m = 3. At finite Reynolds number with kinematic viscosity ν, scalings obey the dissipation laws ɛu ˜ νku/l2 and ɛv ˜ νkv/l2 with kv˜ku/R eln. The value of n is preferably 0 and 2. Different possibilities of scaling laws and symmetry breaking process are discussed at length.

Siim Nestor soovitab : Turbodisko. Camouflage / Siim Nestor

Index Scriptorium Estoniae

Nestor, Siim, 1974-

2006-01-01

Üritusest "Turbodisko" 2. dets. Tallinnas KuKu klubis, indieansambli Bad Apples heliplaadi "When Colours Become Day and Night" (plaadifirmalt Seksound) esitluskontserdist. Saksamaa futuelektroonika ansambli Camouflage albumi "Relocated" esitluskontserdist 3. dets klubis Hollywood (kontserti soojendab läti ansambel STandArt)

Improved GMP-compliant multi-dose production and quality control of 6-[18F]fluoro-L-DOPA.

Science.gov (United States)

Luurtsema, G; Boersma, H H; Schepers, M; de Vries, A M T; Maas, B; Zijlma, R; de Vries, E F J; Elsinga, P H

2017-01-01

6-[ 18 F]Fluoro-L-3,4-dihydroxyphenylalanine (FDOPA) is a frequently used radiopharmaceutical for detecting neuroendocrine and brain tumors and for the differential diagnosis of Parkinson's disease. To meet the demand for FDOPA, a high-yield GMP-compliant production method is required. Therefore, this study aimed to improve the FDOPA production and quality control procedures to enable distribution of the radiopharmaceutical over distances.FDOPA was prepared by electrophilic fluorination of the trimethylstannyl precursor with [ 18 F]F 2 , produced from [ 18 O] 2 via the double-shoot approach, leading to FDOPA with higher specific activity as compared to FDOPA which was synthesized, using [ 18 F]F 2 produced from 20 Ne, leading to FDOPA with a lower specific activity. The quality control of the product was performed using a validated UPLC system and compared with quality control with a conventional HPLC system. Impurities were identified using UPLC-MS. The [ 18 O] 2 double-shoot radionuclide production method yielded significantly more [ 18 F]F 2 with less carrier F 2 than the conventional method starting from 20 Ne. After adjustment of radiolabeling parameters substantially higher amounts of FDOPA with higher specific activity could be obtained. Quality control by UPLC was much faster and detected more side-products than HPLC. UPLC-MS showed that the most important side-product was FDOPA-quinone, rather than 6-hydroxydopa as suggested by the European Pharmacopoeia. The production and quality control of FDOPA were significantly improved by introducing the [ 18 O] 2 double-shoot radionuclide production method, and product analysis by UPLC, respectively. As a result, FDOPA is now routinely available for clinical practice and for distribution over distances.

Dual-time-point O-(2-[{sup 18}F]fluoroethyl)-L-tyrosine PET for grading of cerebral gliomas

Energy Technology Data Exchange (ETDEWEB)

Lohmann, Philipp; Herzog, Hans; Rota Kops, Elena; Stoffels, Gabriele; Judov, Natalie; Filss, Christian; Tellmann, Lutz [Forschungszentrum Juelich, Institute of Neuroscience and Medicine, Juelich (Germany); Galldiks, Norbert [Forschungszentrum Juelich, Institute of Neuroscience and Medicine, Juelich (Germany); University of Cologne, Department of Neurology, Cologne (Germany); Weiss, Carolin [University of Cologne, Department of Neurosurgery, Cologne (Germany); Sabel, Michael [Heinrich-Heine University, Department of Neurosurgery, Duesseldorf (Germany); Coenen, Heinz Hubert [Forschungszentrum Juelich, Institute of Neuroscience and Medicine, Juelich (Germany); Juelich-Aachen Research Alliance (JARA) - Section JARA-Brain, Juelich (Germany); Shah, Nadim Jon [Forschungszentrum Juelich, Institute of Neuroscience and Medicine, Juelich (Germany); Juelich-Aachen Research Alliance (JARA) - Section JARA-Brain, Juelich (Germany); RWTH Aachen University Hospital, Department of Neurology, Aachen (Germany); Langen, Karl-Josef [Forschungszentrum Juelich, Institute of Neuroscience and Medicine, Juelich (Germany); RWTH Aachen University Hospital, Department of Nuclear Medicine, Aachen (Germany); Juelich-Aachen Research Alliance (JARA) - Section JARA-Brain, Juelich (Germany)

2015-10-15

We aimed to evaluate the diagnostic potential of dual-time-point imaging with positron emission tomography (PET) using O-(2-[{sup 18}F]fluoroethyl)-L-tyrosine ({sup 18}F-FET) for non-invasive grading of cerebral gliomas compared with a dynamic approach. Thirty-six patients with histologically confirmed cerebral gliomas (21 primary, 15 recurrent; 24 high-grade, 12 low-grade) underwent dynamic PET from 0 to 50 min post-injection (p.i.) of {sup 18}F-FET, and additionally from 70 to 90 min p.i. Mean tumour-to-brain ratios (TBR{sub mean}) of {sup 18}F-FET uptake were determined in early (20-40 min p.i.) and late (70-90 min p.i.) examinations. Time-activity curves (TAC) of the tumours from 0 to 50 min after injection were assigned to different patterns. The diagnostic accuracy of changes of {sup 18}F-FET uptake between early and late examinations for tumour grading was compared to that of curve pattern analysis from 0 to 50 min p.i. of {sup 18}F-FET. The diagnostic accuracy of changes of the TBR{sub mean} of {sup 18}F-FET PET uptake between early and late examinations for the identification of HGG was 81 % (sensitivity 83 %; specificity 75 %; cutoff - 8 %; p < 0.001), and 83 % for curve pattern analysis (sensitivity 88 %; specificity 75 %; p < 0.001). Dual-time-point imaging of {sup 18}F-FET uptake in gliomas achieves diagnostic accuracy for tumour grading that is similar to the more time-consuming dynamic data acquisition protocol. (orig.)

A new precursor for the preparation of 6-[18F]-fluoro-L-m-tyrosine (FMT): Efficient synthesis and comparison of radiolabeling

International Nuclear Information System (INIS)

VanBrocklin, Henry F.; Blagoev, Milan; Hoepping, Alexander; O'Neil, James P.; Klose, Manuela; Schubiger, Pius A.; Ametamey, Simon

2004-01-01

For the electrophilic preparation of 6-[18F]-Fluoro-L-m-tyrosine (FMT), a PET tracer for measuring changes in dopaminergic function in movement disorders, a novel precursor, N-(tert-butoxycarbonyl)-3- (tert-butoxycarbonyloxy)-6-trimethylstannnyl-L-pheny-lalanine ethyl ester, was synthesized in four steps and 26 percent yield starting from L-m-tyrosine. FMT produced by two methods at two institutions was comparable in decay corrected yield, 25-26 percent, and quality (chemical, enantiomeric, and radiochemical purity and specific activity) as that obtained with the original N-trifluoroacetyl-3-acetyl-6-trimethylstannyl-L-m-tyrosine ethyl ester FMT precursor

The new 1.8 l TFSI engine from Audi. Pt. 2. Mixture formation, combustion method and turbocharging; Der neue 1,8-L-TFSI-Motor von Audi. T. 2. Gemischbildung, Brennverfahren und Aufladung

Energy Technology Data Exchange (ETDEWEB)

Heiduk, Thomas; Kuhn, Michael; Stichlmeir, Maximilian; Unselt, Florian [Audi AG, Ingolstadt (Germany)

2011-07-15

The launch of the new 1.8 l TFSI engine marks the third generation of the successful four-cylinder gasoline engine family from Audi. With consistently reduced frictional losses, the advanced combustion process and new mono-scroll turbocharger and electric wastegate technology, the engine represents a new benchmark in terms of performance and fuel-efficiency. The power plant has already been configured to meet even the strictest future emissions standards worldwide. The mixture formation, the combustion process and the turbocharger of the new engine are described below. The base engine and the thermomanagement system were described in the first part of this article in MTZ 6. (orig.)

Welfare of farmed fish - nutrition, breeding and diseases

DEFF Research Database (Denmark)

Buchmann, Kurt

Proceeding on the workshop on Welfare of fish which was organised by the research school SCOFDA at KU-LIFE on April 11 and 12, 2007. Prooceedings comprise a total of 18 abstracts which were edited by Kurt Buchmann.......Proceeding on the workshop on Welfare of fish which was organised by the research school SCOFDA at KU-LIFE on April 11 and 12, 2007. Prooceedings comprise a total of 18 abstracts which were edited by Kurt Buchmann....

Comparison of the anaesthetic efficacy of different volumes of 4% articaine (1.8 and 3.6 mL) as supplemental buccal infiltration after failed inferior alveolar nerve block.

Science.gov (United States)

Singla, M; Subbiya, A; Aggarwal, V; Vivekanandhan, P; Yadav, S; Yadav, H; Venkatesh, A; Geethapriya, N; Sharma, V

2015-01-01

To compare the anaesthetic efficacy of different volumes (1.8 mL vs. 3.6 mL) of 4% articaine with 1 : 100 000 epinephrine injected as buccal infiltrations after a failed inferior alveolar nerve block (IANB) in patients with symptomatic irreversible pulpitis. Two hundred and thirty-four adult patients, diagnosed with irreversible pulpitis in a mandibular tooth, participated in this multicentre, randomized double-blinded trial. Patients received IANB with 1.8 mL of 4% articaine with 1 : 100 000 epinephrine. Pain during treatment was recorded using the Heft-Parker visual analogue scale (HP VAS). The primary outcome measure, and the definition of 'success', was the ability to undertake pulp chamber access and canal instrumentation with no or mild pain (HP VAS score <55 mm). Patients who experienced 'moderate-to-severe' pain (HP VAS score ≥ 55 mm) were randomly allocated into two groups and received buccal infiltrations with either 1.8 mL or 3.6 mL of 4% articaine with 1 : 100 000 epinephrine. Root canal treatment was re-initiated after 10 min. Success was again defined as no pain or weak/mild pain during endodontic access preparation and instrumentation. Statistical analysis was performed using Mann-Whitney U and chi-square tests. The initial IANB of 4% articaine gave an overall success rate of 37%. The success rate of supplementary buccal infiltration with 1.8 and 3.6 mL volumes was 62% and 64%, respectively. The difference between the success rates of the two volumes was not statistically significant. Increasing the volume of 4% articaine with 1 : 100 000 epinephrine from 1.8 to 3.6 mL, given as supplementary buccal infiltrations after a failed primary IANB with 1.8 mL of 4% articaine with 1 : 100 000, did not improve the anaesthetic success rates in patients with symptomatic irreversible pulpitis. © 2014 International Endodontic Journal. Published by John Wiley & Sons Ltd.

Low carbohydrate diet before 18F-FDG tumor imaging contributes to reduce myocardial 18F-FDG uptake

International Nuclear Information System (INIS)

Miao Weibing; Chen Shaoming; Zheng Shan; Wu Jing; Peng Jiequan; Jiang Zhihong

2014-01-01

Objective: To evaluate whether low carbohydrate diet before 18 F-FDG tumor imaging could reduce myocardial 18 F-FDG uptake. Methods: From April 2011 to January 2012, 70 patients were enrolled in this study.They were randomly divided into control group (34 cases) and test group (36 cases). Patients in control group were on regular diet, while those in test group had low carbohydrate diet in the evening before imaging. Blood samples were taken before injection of 18 F-FDG for the measurement of serum glucose, free fatty acid,insulin and ketone body. Whole body 18 F-FDG tomography was performed with dual-head coincidence SPECT. The myocardial uptake of FDG was assessed visually and scored as 0 for no uptake, 1 for uptake lower than liver, 2 for uptake similar to liver, 3 for uptake higher than liver, and 4 for remarkable uptake.The ratio of myocardium to liver (H/L) was calculated. Two-sample t test, Wilcoxon rank sum test and linear correlation analysis were performed. Results: The myocardial uptake in test group was significantly lower than that in control group with H/L ratios of 0.94±0.57 and 1.50±1.04, respectively (t=-2.75, P<0.05). The concentrations of serum free fatty acid and ketone body in test group were significantly higher than those in control group: (0.671±0.229) mmol/L vs (0.547±0.207) mmol/L and (0.88±0.60) mmol/L vs (0.57±0.32) mmol/L, t=2.38 and 2.67, both P<0.05. The concentrations of glucose and insulin were (5.28±1.06) mmol/L and (35.16±33.70) pmol/L in test group, which showed no significant difference with those in control group ((5.19±0.78) mmol/L and (41.64±35.13) pmol/L, t=0.39 and-0.79, both P>0.05). A negative correlation was found between the myocardial uptake of 18 F-FDG and serum free fatty acid/ketone body concentration (r=-0.40, -0.33, both P<0.01), respectively. There was no correlation between the myocardial uptake of 18 F-FDG and glucose/insulin (r=-0.02, 0.13, both P>0.05), respectively. Conclusion: Low carbohydrate

Radiolabeling and in vitro and in vivo characterization of [18F]FB-[R(8,15,21), L17]-VIP as a PET imaging agent for tumor overexpressed VIP receptors.

Science.gov (United States)

Cheng, Dengfeng; Yin, Duanzhi; Li, Gucai; Wang, Mingwei; Li, Shiqiang; Zheng, Mingqiang; Cai, Hancheng; Wang, Yongxian

2006-12-01

In an effort to develop a peptide-based radiopharmaceutical for the detection of tumors overexpressed vasoactive intestinal peptide receptors with positron emission tomography, we have prepared a novel [R(8,15,21), L17]-VIP peptide for 18F-labeling. This peptide inhibited 125I-VIP binding to rats lung membranes with high affinity [half-maximal inhibitory concentrations (IC50) of 0.12 nm]. Additionally, [R(8,15,21), L17]-VIP showed higher stability than native vasoactive intestinal peptide in vivo of mice. With N-succinimidyl 4-[18F] fluorobenzoate as labeling prosthetic group, [18F]FB-[R(8,15,21), L17]-VIP was obtained in >99% radiochemical purity within 100 min in decay-for-corrected radiochemical yield of 33.6 +/- 3% (n = 5) and a specific radioactivity 255 GBq/micromol at the end of synthesis. Stability of [18F]FB-[R(8,15,21), L17]-VIP in vitro and in vivo were investigated. Biodistribution of this trace was carried out in mice with induced C26 colorectal tumor. Fast clearance of [18F]FB-[R(8,15,21), L17]-VIP from non-target tissues and specific uptakes by tumors realized higher tumor-to-muscle ratio (3.55) and tumor-to-blood ratio (2.37) 60 min postinjection. Clear difference was observed between the blocking and unblocking experiments in biodistribution and whole body radioautography. [18F]FB-[R(8,15,21), L17]-VIP has demonstrated its potential for diagnosing tumors overexpressed vasoactive intestinal peptide receptors both in vitro and in vivo.

Evaluation of D-isomers of 4-borono-2-18F-fluoro-phenylalanine and O-11C-methyl-tyrosine as brain tumor imaging agents: a comparative PET study with their L-isomers in rat brain glioma.

Science.gov (United States)

Kanazawa, Masakatsu; Nishiyama, Shingo; Hashimoto, Fumio; Kakiuchi, Takeharu; Tsukada, Hideo

2018-06-13

The potential of the D-isomerization of 4-borono-2- 18 F-fluoro-phenylalanine ( 18 F-FBPA) to improve its target tumor to non-target normal brain tissue ratio (TBR) was evaluated in rat brain glioma and compared with those of L- and D- 11 C-methyl-tyrosine ( 11 C-CMT). The L- or D-isomer of 18 F-FBPA was injected into rats through the tail vein, and their whole body kinetics and distributions were assessed using the tissue dissection method up to 90 min after the injection. The kinetics of L- and D- 18 F-FBPA or L- and D- 11 C-CMT in the C-6 glioma-inoculated rat brain were measured for 90 or 60 min, respectively, using high-resolution animal PET, and their TBRs were assessed. Tissue dissection analyses showed that D- 18 F-FBPA uptake was significantly lower than that of L- 18 F-FBPA in the brain and abdominal organs, except for the kidney and bladder, reflecting the faster elimination rate of D- 18 F-FBPA than L- 18 F-FBPA from the blood to the urinary tract. PET imaging using 18 F-FBPA revealed that although the brain uptake of D- 18 F-FBPA was significantly lower than that of L- 18 F-FBPA, the TBR of the D-isomer improved to 6.93 from 1.45 for the L-isomer. Similar results were obtained with PET imaging using 11 C-CMT with a smaller improvement in TBR to 1.75 for D- 11 C-CMT from 1.33 for L- 11 C-CMT. The present results indicate that D- 18 F-FBPA is a better brain tumor imaging agent with higher TBR than its original L-isomer and previously reported tyrosine-based PET imaging agents. This improved TBR of D- 18 F-FBPA without any pre-treatments, such as tentative blood-brain barrier disruption using hyperosmotic agents or sonication, suggests that the D-isomerization of BPA results in the more selective accumulation of 10 B in tumor cells that is more effective and less toxic than conventional L-BPA.

Aspects of 6-[18F]fluoro-L-DOPA preparation: precursor synthesis, preparative HPLC purification and determination of radiochemical purity

International Nuclear Information System (INIS)

Fuechtner, F.; Angelberger, P.; Kvaternik, H.; Hammerschmidt, F.; Simovc, B. Peric; Steinbach, J.

2002-01-01

A modified method for the synthesis of the intermediate product N-Boc-3,4-di(Boc-O)-6-iodo-L-phenylalanine ethyl ester of the [ 18 F]FDOPA precursor preparation was developed. With the application of bis-(trifluoroacetoxy)-iodobenzene for the iodination step with elemental iodine the yield of the intermediate can be increased from 12% to 50-60%. By replacing silica-gel-based RP HPLC column by a polymer-based column for semi-preparative purification of [ 18 F]FDOPA from the reaction mixture the radiochemical purity of the final product can be increased up to >99%. For the determination of the radiochemical impurity [ 18 F]fluoride a HPLC method using a column with polymer-based RP material was introduced

KUŞAKLARIN SİYASAL İLETİŞİM KÜLTÜR VE LİDERLİK AÇISINDAN DEĞERLENDİRİLMESİ

OpenAIRE

GÖKTAŞ, Pınar; ÇARIKÇI, İlker Hüseyin

2018-01-01

Kuşaklararası farklılıklar; bireylerin iletişim tarzını vearzu edilen liderlik tarzını etkilemektedir. Tipik kuşak çatışmalarının çoğuiletişimsizlikten kaynaklanmaktadır. Bu sorunu çözmek için hedef kitleye yönelikiletişim tarzı seçilmelidir. Liderlik tarzı açısından ise kuşaklar inandırıcı vegüvenilir bir lider arzusu içindedir. Araştırma kapsamında aynı zamandaaralarındaki farka da değinebilmek adına sessiz kuşak, patlama kuşağı, X, Y ve Zkuşaklarına yer verilmiştir. Bu bağlamda kuşaklar il...

Degree of conversion of resin-based materials cured with dual-peak or single-peak LED light-curing units.

Science.gov (United States)

Lucey, Siobhan M; Santini, Ario; Roebuck, Elizabeth M

2015-03-01

There is a lack of data on polymerization of resin-based materials (RBMs) used in paediatric dentistry, using dual-peak light-emitting diode (LED) light-curing units (LCUs). To evaluate the degree of conversion (DC) of RBMs cured with dual-peak or single-peak LED LCUs. Samples of Vit-l-escence (Ultradent) and Herculite XRV Ultra (Kerr) and fissure sealants Delton Clear and Delton Opaque (Dentsply) were prepared (n = 3 per group) and cured with either one of two dual-peak LCUs (bluephase(®) G2; Ivoclar Vivadent or Valo; Ultradent) or a single-peak (bluephase(®) ; Ivoclar Vivadent). High-performance liquid chromatography and nuclear magnetic resonance spectroscopy were used to confirm the presence or absence of initiators other than camphorquinone. The DC was determined using micro-Raman spectroscopy. Data were analysed using general linear model anova; α = 0.05. With Herculite XRV Ultra, the single-peak LCU gave higher DC values than either of the two dual-peak LCUs (P < 0.05). Both fissure sealants showed higher DC compared with the two RBMs (P < 0.05); the DC at the bottom of the clear sealant was greater than the opaque sealant, (P < 0.05). 2,4,6-trimethylbenzoyldiphenylphosphine oxide (Lucirin(®) TPO) was found only in Vit-l-escence. Dual-peak LED LCUs may not be best suited for curing non-Lucirin(®) TPO-containing materials. A clear sealant showed a better cure throughout the material and may be more appropriate than opaque versions in deep fissures. © 2014 BSPD, IAPD and John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Germination of somatic embryos of Psidium guajava L. cv. Cuban Red Dwarf EEA 18-40 in temporary immersion systems

Directory of Open Access Journals (Sweden)

Jorge Vilchez Perozo

2001-04-01

Full Text Available Somatic embryo germination of Psidium guajava L. cv. Cuban Red Dwarf EEA 18-40 in temporary immersion systems (TIS, in which somatic embryos were cultured in the heart-torpedo stage in MS mediun at mayor half strength salt and suplemented with: 0.25 mg.l-1 of 6-bencilaminopurine (6-BAP, 10 mg.l-1 of Biobras-6 (analogous of brasinoesteriode and 20 g.l-1 of sucrose. As control was used solid cultivation medium (2.5 g.l-1 Gellan gum, Spectrum® of same composition to the one used in the TIS. The variables germination percentage and fresh weight were evaluated statistically. After ten weeks of cultivation the largest values in germination percentage (91.04% and fresh weight (1.22 g were obtained in the TIS, being statistically different to those obtained in solid medium (9.79% and 1.03 g, respectively. Key words: in vitro plant, guayaba, regeneration, RITA®,somatic embryogenesis

Pusaudžu problemātiskas uzvedības saistības ar viņu piesaistes stilu un vecāku audzināšanas stilu ģimenē

OpenAIRE

Zamberga, Zane

2006-01-01

Maģistra darba pētījuma mērķis bija noskaidrot pusaudžu uzvedības traucējumu, piesaistes stilu un vecāku audzināšanas stilu savstarpējo saistību pusaudžu pašnovērtējumā, un, kāda ir savstarpējā ietekme (multiplās regresijas analīzes rezultātā) piesaistes stilam un vecāku audzināšanas stilam, iepretim uzvedības pašnovērtējumam. Pētījuma izlasi veido 60 pusaudži vcecumā no 14 – 16 gadiem. Tika aptaujāti Latvijas vispārizglītojošo skolu 7. un 8. klases skolēni: 30 meitenes un 30 zēni. Pētījumā...

Striatal kinetics of [11C]-(+)-nomifensine and 6-[18F]fluoro-L-dopa in Parkinson's disease measured with positron emission tomography

International Nuclear Information System (INIS)

Tedroff, J.; Aquilonius, S.-M.; Laihinen, A.; Rinne, U.; Hartvig, P.; Anderson, J.; Lundqvist, H.; Haaparanta, M.; Solin, O.; Antoni, G.; Gee, A.D.; Ulin, J.; Laangstroem, B.

1990-01-01

The kinetics in brain of the dopamine reuptake blocking agent [ 11 C]-(+)-nomifensine and the L-dopa analogue 6-[ 18 F]fluoro-L-dopa were compared in 3 patients with idopathic Parkinson's disease and agematched healthy volunteers using positron emission tomography. Regional uptake was analyzed and quantified according to a 3-compartment model. Retention of both tracers in striatal regions of the parkinsonian patients were reduced compared with the healthy volunteers mainly in the putamen, while the caudate nuclleus was only mildly affected. The reductions were considerably less than the decrease previously reported postmortem for striatal dopamine content in the basal ganglia of patients with Parkinson's disease. A fairly constant ratio between 6-[ 18 F]fluoro-L-dopa utilization and [ 11 C]-(+)-nomifensine binding in the caudate nucleus and the putamen were found in both groups unrelated to the size of the estimated parameters. This indicates that a limiting factor for the utilization of exogenous levodopa in Parkinsons's disease may be a reduced transport capacity for the amino acid into the dopaminergic terminals. (author)

A comparative study of homemade C18 and commercial C18 sorbents for preconcentration of lead by minicolumn solid phase extraction

International Nuclear Information System (INIS)

Maltez, H.F.; Curtius, A.J.; Carasek, E.; Melo, L.F.C.; Sales Fontes Jardim, I.C.; Nascimento de Queiroz do, S.C.

2004-01-01

A comparative study of commercial C 18 chemically immobilized on silica and homemade C 18 , as sorbents for Pb complexed with 0,0-diethyl-dithiophosphate (DDTP) in a flow injection preconcentration system is reported. The homemade C 18 sorbent was obtained by sorption of poly(methyloctadecylsiloxane) (PMODS) on the silica support followed by immobilization using thermal treatment. The method follows the concept of green chemistry, since there are no toxic residues after synthesis. The complexed Pb was formed in 1.0 mol L -1 HCI medium and retained on the minicolumn filled with the sorbents. The elution was carried out using ethanol, and the richest 210 μL fraction was collected and analyzed by flame atomic absorption spectrometry. Chemical and flow variables were optimized for each sorbent. The results demonstrated that the performance of the proposed homemade C 18 sorbent for preconcentration of Pb complexed with DDTP is very similar to commercial C 18 chemically bonded on silica. By processing 25 mL, the enrichment factors were 129 and 125 for commercial C 18 and homemade C 18 , respectively. The limit of detection for commercial and homemade C 18 was 0.2 μg L -1 and 0.6 μg L -1 , respectively. The relative standard deviation (RSD) was lower than 1.2 % for both sorbents for a Pb concentration of 100 μg L -1 . The method was also applied successfully to the analysis of water samples, and the accuracy was tested by recovery measurements on spiked samples and biological reference material. (author)

Overeating Behavior and Striatal Dopamine with 6-[18F]-Fluoro-L--Tyrosine PET

Directory of Open Access Journals (Sweden)

Claire E. Wilcox

2010-01-01

Full Text Available Eating behavior may be affected by dopamine synthesis capacity. In this study, 6-[18F]-fluoro-L--tyrosine (FMT positron emission tomography (PET uptake in striatal subregions was correlated with BMI (kg/m2 and an estimate of the frequency of prior weight loss attempts in 15 healthy subjects. BMI was negatively correlated with FMT uptake in the dorsal caudate. Although the association between BMI and FMT uptake in the dorsal caudate was not significant upon correction for age and sex, the association fell within the range of a statistical trend. Weight loss attempts divided by years trying was also negatively correlated with FMT uptake in the dorsal putamen (=.05. These results suggest an association between low dorsal striatal presynaptic dopamine synthesis capacity and overeating behavior.

Vecāku prombūtnes un klātesošā vecāka audzināšanas pieejas saistība ar pusaudžu depresijas pazīmēm

OpenAIRE

Ločmele, Renāte

2014-01-01

Pētījuma mērķis bija noskaidrot, kādas ir saistības starp vecāku prombūtni, klātesošā vecāka audzināšanas pieeju un pusaudžu depresijas pazīmēm. Pētījumā piedalījās 62 respondenti – 37 meitenes un 25 zēni vecumā no 11 līdz 16 gadiem. Respondentu vidējais vecums bija 14 gadi. Tie tika sadalīti divās grupās: vienā grupā bija pusaudži, kuriem viens no vecākiem atrodas prombūtnē (n=31), otrā grupā bija pusaudži, kas dzīvo kopā ar abiem vecākiem ( n=31). Datu ievākšanai tika izmantotas sekojoš...

Rapid detection of Lactobacillus kefiranofaciens in kefir grain and kefir milk using newly developed real-time PCR.

Science.gov (United States)

Kim, Dong-Hyeon; Chon, Jung-Whan; Kim, Hong-Seok; Yim, Jin-Hyeok; Kim, Hyunsook; Seo, Kun-Ho

2015-04-01

Lactobacillus kefiranofaciens is an indicator microorganism for kefir and a key factor in kefir grain formation and kefiran production. We designed a novel real-time PCR primer and probe set, LKF_KU504, for the rapid detection of L. kefiranofaciens. In inclusivity and exclusivity tests, only 14 L. kefiranofaciens strains were positive among 61 microorganisms, indicating 100 % sensitivity and specificity. The LKF_KU504 set also differentiated kefir milk from 30 commercial nonkefir yogurts. The levels of L. kefiranofaciens in kefir grain and kefir milk were significantly different, indicating L. kefiranofaciens was more concentrated in kefir grain than in kefir milk.

{sup 18}F-FBPA as a tumor-specific probe of L-type amino acid transporter 1 (LAT1): a comparison study with {sup 18}F-FDG and {sup 11}C-Methionine PET

Energy Technology Data Exchange (ETDEWEB)

Watabe, Tadashi [Osaka University Graduate School of Medicine, Department of Nuclear Medicine and Tracer Kinetics, Osaka (Japan); Osaka University Graduate School of Medicine, PET Molecular Imaging Center, Osaka (Japan); Ikeda, Hayato; Aoki, Masanao [Osaka University Graduate School of Medicine, Department of Nuclear Medicine and Tracer Kinetics, Osaka (Japan); Nagamori, Shushi; Wiriyasermkul, Pattama; Tanaka, Yoko; Hagiwara, Kohei; Kanai, Yoshikatsu [Osaka University Graduate School of Medicine, Department of Bio-system Pharmacology, Osaka (Japan); Naka, Sadahiro [Osaka University, Osaka University Graduate School of Medicine, Osaka University Hospital, Osaka (Japan); Kanai, Yasukazu [Osaka University Graduate School of Medicine, PET Molecular Imaging Center, Osaka (Japan); Osaka University Graduate School of Medicine, Department of Molecular Imaging in Medicine, Osaka (Japan); Shimosegawa, Eku [Osaka University Graduate School of Medicine, Department of Nuclear Medicine and Tracer Kinetics, Osaka (Japan); Osaka University Graduate School of Medicine, PET Molecular Imaging Center, Osaka (Japan); Osaka University, Osaka University Graduate School of Medicine, Osaka University Hospital, Osaka (Japan); Hatazawa, Jun [Osaka University Graduate School of Medicine, Department of Nuclear Medicine and Tracer Kinetics, Osaka (Japan); Osaka University Graduate School of Medicine, PET Molecular Imaging Center, Osaka (Japan); Osaka University, Immunology Frontier Research Center, Osaka (Japan)

2017-02-15

The purpose of this study was to evaluate the usefulness of L-4-borono-2-{sup 18}F-fluoro-phenylalanine ({sup 18}F-FBPA) as a tumor-specific probe, in comparison to {sup 18}F-FDG and {sup 11}C-methionine (Met), focusing on its transport selectivity by L-type amino acid transporter 1 (LAT1), which is highly upregulated in cancers. Cellular analyses of FBPA were performed to evaluate the transportability and K{sub m} value. PET studies were performed in rat xenograft models of C6 glioma (n = 12) and in rat models of turpentine oil-induced subcutaneous inflammation (n = 9). The kinetic parameters and uptake values on static PET images were compared using the one-tissue compartment model (K{sub 1}, k{sub 2}) and maximum standardized uptake value (SUVmax). The cellular analyses showed that FBPA had a lower affinity to a normal cell-type transporter LAT2 and induced less efflux through LAT2 among FBPA, Met, and BPA, while the efflux through LAT1 induced by FBPA was similar among the three compounds. The K{sub m} value of {sup 18}F-FBPA for LAT1 (196.8 ± 11.4 μM) was dramatically lower than that for LAT2 (2813.8 ± 574.5 μM), suggesting the higher selectivity of {sup 18}F-FBPA for LAT1. K{sub 1} and k{sub 2} values were significantly smaller in {sup 18}F-FBPA PET (K{sub 1} = 0.04 ± 0.01 ml/ccm/min and k{sub 2} = 0.07 ± 0.01 /min) as compared to {sup 11}C-Met PET (0.22 ± 0.09 and 0.52 ± 0.10, respectively) in inflammatory lesions. Static PET analysis based on the SUVmax showed significantly higher accumulation of {sup 18}F-FDG in the tumor and inflammatory lesions (7.2 ± 2.1 and 4.6 ± 0.63, respectively) as compared to both {sup 18}F-FBPA (3.2 ± 0.40 and 1.9 ± 0.19) and {sup 11}C-Met (3.4 ± 0.43 and 1.6 ± 0.11). No significant difference was observed between {sup 18}F-FBPA and {sup 11}C-Met in the static PET images. This study shows the utility of {sup 18}F-FBPA as a tumor-specific probe of LAT1 with low accumulation in the inflammatory lesions. (orig.)

Wpływ wysiłku fizycznego na funkcję układu oddechowego w twardzinie układowej

OpenAIRE

Stanisław Sierakowski; Ewa Gińdzieńska-Sieśkiewicz; Maciej Kaczmarski; Zenon Siergiejko; Grzegorz Siergiejko; Piotr Siergiejko; Justyna Fryc

2010-01-01

Cel: Powikłania ze strony układu oddechowego stanowią główną przyczynę zgonów pacjentów z twardziną układową (TU). Tętniczenadciśnienie płucne i śródmiąższowa choroba płuc stanowią najistotniejszez nich. Pacjenci są jednak często zdiagnozowani dopierow późnym okresie choroby, dlatego też istotne jest opracowaniemetody diagnostycznej do wczesnego wykrywania tych powikłań.Celem pracy była ocena wpływu wysiłku fizycznego na zmiany parametrówoddechowych. Materiały i metody: Badania przeprowadzono...

Radiosynthesis of F-18 labeled cytidine analog 2'-fluoro-5-iodo-l-β-D-arabinofuranosylcytosine ([18F]FIAC)

International Nuclear Information System (INIS)

Wu, C.-Y.; Chan, P.-C.; Chang, W.-T.; Liu, R.-S.; Alauddin, Mian M.; Wang, H-E.

2009-01-01

We reported the synthesis of 2'-deoxy-2'-[ 18 F]fluoro-5-iodo-1-β-D-arabinofuranosyl-5-iodo-cytosine ([ 18 F]FIAC) with 15-20% radiochemical yield (decay corrected) in 3.5 h. 2-deoxy-2-[ 18 F]fluoro-1,3,5-tri-O-benzoyl-α-D-arabinofuranose was prepared following literature procedures with some modifications (yield>70%). The 18 F-fluorosugar was converted to 1-bromo- 18 F-fluorosugar, and then coupled with 5-iodocytocine silyl ether. A mixture of acetonitrile (ACN) and 1,2-dichloroethane (DCE) were employed to achieve optimum radiochemical yield and acceptable β-anomer selectivity (α/β=1/3). After hydrolyzed with sodium methoxide, the crude product was purified using HPLC to afford the β-[ 18 F]FIAC with high radiochemical purity (≥98%).

Expression of biologically active murine interleukin-18 in Lactococcus lactis.

Science.gov (United States)

Feizollahzadeh, Sadegh; Khanahmad, Hossein; Rahimmanesh, Ilnaz; Ganjalikhani-Hakemi, Mazdak; Andalib, Alireza; Sanei, Mohammad Hossein; Rezaei, Abbas

2016-11-01

The food-grade bacterium Lactococcus lactis is increasingly used for heterologous protein expression in therapeutic and industrial applications. The ability of L. lactis to secrete biologically active cytokines may be used for the generation of therapeutic cytokines. Interleukin (IL)-18 enhances the immune response, especially on mucosal surfaces, emphasizing its therapeutic potential. However, it is produced as an inactive precursor and has to be enzymatically cleaved for maturation. We genetically manipulated L. lactis to secrete murine IL-18. The mature murine IL-18 gene was inserted downstream of a nisin promoter in pNZ8149 plasmid and the construct was used to transform L. lactis NZ3900. The transformants were selected on Elliker agar and confirmed by restriction enzyme digestion and sequencing. The expression and secretion of IL-18 protein was verified by SDS-PAGE, western blotting and ELISA. The biological activity of recombinant IL-18 was determined by its ability to induce interferon (IFN)-γ production in L. lactis co-cultured with murine splenic T cells. The amounts of IL-18 in bacterial lysates and supernatants were 3-4 μg mL -1 and 0.6-0.7 ng mL -1 , respectively. The successfully generated L. lactis strain that expressed biologically active murine IL-18 can be used to evaluate the possible therapeutic effects of IL-18 on mucosal surfaces. © FEMS 2016. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Comparison of {sup 18}F-FET and {sup 18}F-FDG PET in brain tumors

Energy Technology Data Exchange (ETDEWEB)

Pauleit, Dirk; Stoffels, Gabriele [Institute of Neuroscience and Medicine, Forschungszentrum Juelich, D-52425 Juelich (Germany); Bachofner, Ansgar [Clinic of Nuclear Medicine, Heinrich-Heine-University, D-40001 Duesseldorf (Germany); Floeth, Frank W.; Sabel, Michael [Department of Neurosurgery, Heinrich-Heine-University, D-40001 Duesseldorf (Germany); Herzog, Hans; Tellmann, Lutz [Institute of Neuroscience and Medicine, Forschungszentrum Juelich, D-52425 Juelich (Germany); Jansen, Paul [Institute of Advanced Simulation, Forschungszentrum Juelich, D-52425 Juelich (Germany); Reifenberger, Guido [Department of Neuropathology, Heinrich-Heine-University, D-40001 Duesseldorf (Germany); Hamacher, Kurt; Coenen, Heinz H. [Institute of Neuroscience and Medicine, Forschungszentrum Juelich, D-52425 Juelich (Germany); Langen, Karl-Josef [Institute of Neuroscience and Medicine, Forschungszentrum Juelich, D-52425 Juelich (Germany)], E-mail: k.j.langen@fz-juelich.de

2009-10-15

The purpose of this study was to compare the diagnostic value of positron emission tomography (PET) using [{sup 18}F]-fluorodeoxyglucose ({sup 18}F-FDG) and O-(2-[{sup 18}F]fluoroethyl)-L-tyrosine ({sup 18}F-FET) in patients with brain lesions suspicious of cerebral gliomas. Methods: Fifty-two patients with suspicion of cerebral glioma were included in this study. From 30 to 50 min after injection of 180 MBq {sup 18}F-FET, a first PET scan ({sup 18}F-FET scan) was performed. Thereafter, 240 MBq {sup 18}F-FDG was injected and a second PET scan was acquired from 30 to 60 min after the second injection ({sup 18}F-FET/{sup 18}F-FDG scan). The cerebral accumulation of {sup 18}F-FDG was calculated by decay corrected subtraction of the {sup 18}F-FET scan from the {sup 18}F-FET/{sup 18}F-FDG scan. Tracer uptake was evaluated by visual scoring and by lesion-to-background (L/B) ratios. The imaging results were compared with the histological results and prognosis. Results: Histology revealed 24 low-grade gliomas (LGG) of World Health Organization (WHO) Grade II and 19 high-grade gliomas (HGG) of WHO Grade III or IV, as well as nine others, mainly benign histologies. The gliomas showed increased {sup 18}F-FET uptake (>normal brain) in 86% and increased {sup 18}F-FDG uptake (>white matter) in 35%. {sup 18}F-FET PET provided diagnostically useful delineation of tumor extent while this was impractical with {sup 18}F-FDG due to high tracer uptake in the gray matter. A local maximum in the tumor area for biopsy guidance could be identified with {sup 18}F-FET in 76% and with {sup 18}F-FDG in 28%. The L/B ratios showed significant differences between LGG and HGG for both tracers but considerable overlap so that reliable preoperative grading was not possible. A significant correlation of tracer uptake with overall survival was found with {sup 18}F-FDG only. In some benign lesions like abscesses, increased uptake was observed for both tracers indicating a limited specificity of both

Whole-body kinetics and dosimetry of cis-4-[18F]fluoro-l-proline

International Nuclear Information System (INIS)

Boerner, Anne R.; Langen, Karl-J.; Herzog, Hans; Hamacher, Kurt; Mueller-Mattheis, Volker; Schmitz, Thomas; Ackermann, Rolf; Coenen, Heinz H.

2001-01-01

The whole-body distribution of 4-cis[ 18 F]fluoro-L-proline (cis-FPro) was studied in six patients with urological tumors by PET. Based on the IMEDOSE and MIRDOSE procedures radiation absorbed doses were estimated from whole-body PET scans acquired at 1 and 3-5 h after i.v. injection of 400 MBq cis-FPro. Cis-FPro showed high retention in the renal cortex and a slight uptake in liver and pancreas. Urinary excretion ranged from 12 to 19% at 5 h p.i. Highest absorbed doses were found for the urinary bladder wall and the kidneys (44.1/44.0 μGy/MBq). The effective dose according to ICRP 60 was 15.1 μSv/MBq for adults. This leads to an effective dose of 6.0 mSv in a PET study using 400 MBq cis-FPro

Whole-body kinetics and dosimetry of cis-4-[(18)F]fluoro-L-proline.

Science.gov (United States)

Börner, A R; Langen, K J; Herzog, H; Hamacher, K; Müller-Mattheis, V; Schmitz, T; Ackermann, R; Coenen, H H

2001-04-01

The whole-body distribution of 4-cis[(18)F]fluoro-L-proline (cis-FPro) was studied in six patients with urological tumors by PET. Based on the IMEDOSE and MIRDOSE procedures radiation absorbed doses were estimated from whole-body PET scans acquired at 1 and 3-5 h after i.v. injection of 400 MBq cis-FPro. Cis-FPro showed high retention in the renal cortex and a slight uptake in liver and pancreas. Urinary excretion ranged from 12 to 19% at 5 h p.i. Highest absorbed doses were found for the urinary bladder wall and the kidneys (44.1/44.0 microGy/mbq). The effective dose according to ICRP 60 was 15.1 microSv/mbq for adults. This leads to an effective dose of 6.0 mSv in a PET study using 400 MBq cis-FPro.

DNA-PK dependent targeting of DNA-ends to a protein complex assembled on matrix attachment region DNA sequences

International Nuclear Information System (INIS)

Mauldin, S.K.; Getts, R.C.; Perez, M.L.; DiRienzo, S.; Stamato, T.D.

2003-01-01

Full text: We find that nuclear protein extracts from mammalian cells contain an activity that allows DNA ends to associate with circular pUC18 plasmid DNA. This activity requires the catalytic subunit of DNA-PK (DNA-PKcs) and Ku since it was not observed in mutants lacking Ku or DNA-PKcs but was observed when purified Ku/DNA-PKcs was added to these mutant extracts. Competition experiments between pUC18 and pUC18 plasmids containing various nuclear matrix attachment region (MAR) sequences suggest that DNA ends preferentially associate with plasmids containing MAR DNA sequences. At a 1:5 mass ratio of MAR to pUC18, approximately equal amounts of DNA end binding to the two plasmids were observed, while at a 1:1 ratio no pUC18 end-binding was observed. Calculation of relative binding activities indicates that DNA-end binding activities to MAR sequences was 7 to 21 fold higher than pUC18. Western analysis of proteins bound to pUC18 and MAR plasmids indicates that XRCC4, DNA ligase IV, scaffold attachment factor A, topoisomerase II, and poly(ADP-ribose) polymerase preferentially associate with the MAR plasmid in the absence or presence of DNA ends. In contrast, Ku and DNA-PKcs were found on the MAR plasmid only in the presence of DNA ends. After electroporation of a 32P-labeled DNA probe into human cells and cell fractionation, 87% of the total intercellular radioactivity remained in nuclei after a 0.5M NaCl extraction suggesting the probe was strongly bound in the nucleus. The above observations raise the possibility that DNA-PK targets DNA-ends to a repair and/or DNA damage signaling complex which is assembled on MAR sites in the nucleus

"1"8F-FBPA as a tumor-specific probe of L-type amino acid transporter 1 (LAT1): a comparison study with "1"8F-FDG and "1"1C-Methionine PET

International Nuclear Information System (INIS)

Watabe, Tadashi; Ikeda, Hayato; Aoki, Masanao; Nagamori, Shushi; Wiriyasermkul, Pattama; Tanaka, Yoko; Hagiwara, Kohei; Kanai, Yoshikatsu; Naka, Sadahiro; Kanai, Yasukazu; Shimosegawa, Eku; Hatazawa, Jun

2017-01-01

The purpose of this study was to evaluate the usefulness of L-4-borono-2-"1"8F-fluoro-phenylalanine ("1"8F-FBPA) as a tumor-specific probe, in comparison to "1"8F-FDG and "1"1C-methionine (Met), focusing on its transport selectivity by L-type amino acid transporter 1 (LAT1), which is highly upregulated in cancers. Cellular analyses of FBPA were performed to evaluate the transportability and K_m value. PET studies were performed in rat xenograft models of C6 glioma (n = 12) and in rat models of turpentine oil-induced subcutaneous inflammation (n = 9). The kinetic parameters and uptake values on static PET images were compared using the one-tissue compartment model (K_1, k_2) and maximum standardized uptake value (SUVmax). The cellular analyses showed that FBPA had a lower affinity to a normal cell-type transporter LAT2 and induced less efflux through LAT2 among FBPA, Met, and BPA, while the efflux through LAT1 induced by FBPA was similar among the three compounds. The K_m value of "1"8F-FBPA for LAT1 (196.8 ± 11.4 μM) was dramatically lower than that for LAT2 (2813.8 ± 574.5 μM), suggesting the higher selectivity of "1"8F-FBPA for LAT1. K_1 and k_2 values were significantly smaller in "1"8F-FBPA PET (K_1 = 0.04 ± 0.01 ml/ccm/min and k_2 = 0.07 ± 0.01 /min) as compared to "1"1C-Met PET (0.22 ± 0.09 and 0.52 ± 0.10, respectively) in inflammatory lesions. Static PET analysis based on the SUVmax showed significantly higher accumulation of "1"8F-FDG in the tumor and inflammatory lesions (7.2 ± 2.1 and 4.6 ± 0.63, respectively) as compared to both "1"8F-FBPA (3.2 ± 0.40 and 1.9 ± 0.19) and "1"1C-Met (3.4 ± 0.43 and 1.6 ± 0.11). No significant difference was observed between "1"8F-FBPA and "1"1C-Met in the static PET images. This study shows the utility of "1"8F-FBPA as a tumor-specific probe of LAT1 with low accumulation in the inflammatory lesions. (orig.)

The D18 diffractometer for neutron interferometry at the I.L.L

International Nuclear Information System (INIS)

Bauspiess, W.

1978-01-01

Three things are needed for neutron interferometry: an interferometer (a crystal in the case of Bragg diffraction interferometry), a neutron source, and a device to select and handle the neutrons that shall be used. It is this last technical aspect of neutron interferometry which is discussed in the paper, using as an example the new diffractometer for neutron interferometry that is being built at the I.L.L. Results of performance tests are not presently available but its characteristics are visible from the design. The experimental figures given in the paper refer to experiments performed with the prototype machine, or are extrapolated from said experiments

An Interindividual Comparison of O-(2- [18F]Fluoroethyl)-L-Tyrosine (FET)– and L-[Methyl-11C]Methionine (MET)–PET in Patients With Brain Gliomas and Metastases

International Nuclear Information System (INIS)

Grosu, Anca-Ligia; Astner, Sabrina T.; Riedel, Eva; Nieder, Carsten; Wiedenmann, Nicole; Heinemann, Felix; Schwaiger, Markus

2011-01-01

Purpose: L-[methyl- 11 C]methionine (MET)–positron emission tomography (PET) has a high sensitivity and specificity for imaging of gliomas and metastatic brain tumors. The short half-life of 11 C (20 minutes) limits the use of MET-PET to institutions with onsite cyclotron. O-(2- [ 18 F]fluoroethyl)-L-tyrosine (FET) is labeled with 18 F (half-life, 120 minutes) and could be used much more broadly. This study compares the uptake of FET and MET in gliomas and metastases, as well as treatment-induced changes. Furthermore, it evaluates the gross tumor volume (GTV) of gliomas defined on PET and magnetic resonance imaging (MRI). Methods and Materials: We examined 42 patients with pretreated gliomas (29 patients) or brain metastases (13 patients) prospectively by FET- and MET-PET on the same day. Uptake of FET and MET was quantified by standardized uptake values. Imaging contrast was assessed by calculating lesion–to–gray matter ratios. Tumor extension was quantified by contouring GTV in 17 patients with brain gliomas. Gross tumor volume on PET was compared with GTV on MRI. Sensitivity and specificity of MET- and FET-PET for differentiation of viable tumor from benign changes were evaluated by comparing the PET result with histology or clinical follow-up. Results: There was a strong linear correlation between standardized uptake values calculated for both tracers in cortex and lesions: r = 0.78 (p = 0.001) and r = 0.84 (p 18 F]fluoroethyl)-L-tyrosine–PET and MET-PET provide comparable diagnostic information on gliomas and brain metastases. Like MET-PET, FET-PET can be used for differentiation of residual or recurrent tumor from treatment-related changes/pseudoprogression, as well as for delineation of gliomas.

The impact of the snow cover on sea-ice thickness products retrieved by Ku-band radar altimeters

Science.gov (United States)

Ricker, R.; Hendricks, S.; Helm, V.; Perovich, D. K.

2015-12-01

Snow on sea ice is a relevant polar climate parameter related to ocean-atmospheric interactions and surface albedo. It also remains an important factor for sea-ice thickness products retrieved from Ku-band satellite radar altimeters like Envisat or CryoSat-2, which is currently on its mission and the subject of many recent studies. Such satellites sense the height of the sea-ice surface above the sea level, which is called sea-ice freeboard. By assuming hydrostatic equilibrium and that the main scattering horizon is given by the snow-ice interface, the freeboard can be transformed into sea-ice thickness. Therefore, information about the snow load on hemispherical scale is crucial. Due to the lack of sufficient satellite products, only climatological values are used in current studies. Since such values do not represent the high variability of snow distribution in the Arctic, they can be a substantial contributor to the total sea-ice thickness uncertainty budget. Secondly, recent studies suggest that the snow layer cannot be considered as homogenous, but possibly rather featuring a complex stratigraphy due to wind compaction and/or ice lenses. Therefore, the Ku-band radar signal can be scattered at internal layers, causing a shift of the main scattering horizon towards the snow surface. This alters the freeboard and thickness retrieval as the assumption that the main scattering horizon is given by the snow-ice interface is no longer valid and introduces a bias. Here, we present estimates for the impact of snow depth uncertainties and snow properties on CryoSat-2 sea-ice thickness retrievals. We therefore compare CryoSat-2 freeboard measurements with field data from ice mass-balance buoys and aircraft campaigns from the CryoSat Validation Experiment. This unique validation dataset includes airborne laser scanner and radar altimeter measurements in spring coincident to CryoSat-2 overflights, and allows us to evaluate how the main scattering horizon is altered by the

The Ixodes (Acari: Ixodidae) of Mexico: Parasite-Host and Host-Parasite Checklists

Science.gov (United States)

2007-08-20

en Peligro de Extinción. Comisión Nacional para el Cono- cimiento y Uso de la Biodiversidad, Fondo de Cultura Económica, Instituto de Ecología, UNAM...the largest genus of ticks in the world, currently comprising 243 species (Guglielmone et al. 2006), more than one quarter of the global tick fauna ...include it in the Mexican tick fauna . Ixodes bequaerti Cooley and Kohls Previous record CHIAPAS: 1&, Catharinus (sic), 4-V-1942, NA [Cooley & Kohls, 1945

Eğirdir Gölü ve çevresinde turizm gelişiminin sürdürülebilirliği üzerine değerlendirmeler

OpenAIRE

Korkmaz, Mehmet; Başkalkan, Sibel Nihal

2011-01-01

Eğirdir Gölü, kuş gözlemciliği, su sporları, mağara turizmi, yamaç paraşütçülüğü gibi çok çeşitli aktivite olanakları ve çevresinde yer alan doğal korunan alanları ile doğa turizmi, etrafındaki tarım alanları ile tarım turizmi (agroturizm) ve göl çevresindeki kutsal kabul edilen alanlar ile de inanç turizmi açısından önemli bir potansiyele sahiptir. Geçmişten günümüze yapılan uygulamaların yanı sıra 2008 yılında tamamlanan Eğirdir Gölü Yönetim Planı ve Kovada Gölü Milli Parkı Uzun Devreli Gel...

PRODUCTION OF PLANTARCIN BY LACTOBACILLUS PLANTARUM SR18

Directory of Open Access Journals (Sweden)

Wagih El-Shouny

2012-06-01

Full Text Available Out of 86 lactobacilli previously screened in our laboratory, Lactobacillus plantarum SR18 isolated from yoghurt revealed the largest detected inhibition zone against the selected indicator Streptococcus salivarius 5. The obtained electrophoretic patterns revealed that L. plantarum SR18 was free from plasmids. Exposure of 6 h growing L. plantarum culture to T-8M, 3B ultraviolet B lamp (8w, 220v & 312 nm for 2 h and subsequent growth for further 24 h resulted in an increase of cell-bound bacteriocin titer reached 2 fold at 12 h. Whereas bacteriocin secreted in the culture filtrate was not affected by UV irradiation. Plantarcin SR18 production was maximal (12800 AU/ml between 12 and 18 h by incubation of the culture at 37°C and pH 5-7 in candle jar (CO2. The bacteriocin bound to the cells and that secreted into the culture filtrate of L. plantarum SR18 were precipitated by 75% ammomium sulphate, dialysed and further purified by Gel filtration on Sephadex G-100. The specific activities (AU/mg protein were increased by a factor of about 5.3 and 2.35 for plantarcins purified from proteins bound to the cell of L. plantarum SR18 (plantarcin SR18 a and that secreted into the culture filtrate (plantarcin SR18 b, respectively. Gel filtration of plantarcin SR18a resulted in moderate antibacterial activity (3200 AU/ml and very high activity (25600 AU/ml of plantarcin SR18b.

Hexagonal perovskites with cationic vacancies. 8. Vibrational spectroscopic investigations on rhombohedral 18 L-stacking polytypes Ba/sub 6/B/sub 2/sup(III)vacantW/sub 3/sup(VI)O/sub 18/

Energy Technology Data Exchange (ETDEWEB)

Schittenhelm, H J; Fadini, A; Kemmler-Sack, S [Tuebingen Univ. (Germany, F.R.)

1979-10-01

The vibrational spectra of the 18 L stacking polytypes Ba/sub 6/B/sub 2/sup(III)vacant W/sub 3/O/sub 18/ (space group R3m; sequence (hhcccc)/sub 3/) with Bsup(III) = Lu, Y are reported. The octahedral net consists of W/sub 2/vacantO/sub 12/ and WO/sub 6/ groups, which are isolated from each other by the Ba and B ions. An assignment of the vibrational frequencies has been made with the aid of factor group analysis. For the W/sub 2/vacantO/sub 12/ block a complete force constant calculation is reported.

Exposure to power frequency magnetic fields suppresses X-ray-induced apoptosis transiently in Ku80-deficient xrs5 cells

International Nuclear Information System (INIS)

Tian, Furong; Nakahara, Takehisa; Yoshida, Masami; Honda, Naoko; Hirose, Hideki; Miyakoshi, Junji

2002-01-01

In an attempt to determine whether exposure to extremely low frequency (ELF) electromagnetic fields can affect cells, Ku80-deficient cells (xrs5) and Ku80-proficient cells (CHO-K1) were exposed to ELF electromagnetic fields. Cell survival, and the levels of the apoptosis-related genes p21, p53, phospho-p53 (Ser 15 ), caspase-3 and the anti-apoptosis gene bcl-2 were determined in xrs5 and CHO-K1 cells following exposure to ELF electromagnetic fields and X-rays. It was found that exposure of xrs5 and CHO-K1 cells to 60 Hz ELF electromagnetic fields had no effect on cell survival, cell cycle distribution and protein expression. Exposure of xrs5 cells to 60 Hz ELF electromagnetic fields for 5 h after irradiation significantly inhibited G 1 cell cycle arrest induced by X-rays (1 Gy) and resulted in elevated bcl-2 expression. A significant decrease in the induction of p53, phospho-p53, caspase-3 and p21 proteins was observed in xrs5 cells when irradiation by X-rays (8 Gy) was followed by exposure to 5 mT ELF magnetic fields. Exposure of xrs5 cells to the ELF electromagnetic fields for 10 h following irradiation significantly decreased X-ray-induced apoptosis from about 1.7% to 0.7%. However, this effect was not found in CHO-K1 cells within 24 h of irradiation by X-rays alone and by X-rays combined with ELF electromagnetic fields. Exposure of xrs5 cells to 60 Hz ELF electromagnetic fields following irradiation can affect cell cycle distribution and transiently suppress apoptosis by decreasing the levels of caspase-3, p21, p53 and phospho-p53 and by increasing bcl-2 expression

USP22 Induces Cisplatin Resistance in Lung Adenocarcinoma by Regulating γH2AX-Mediated DNA Damage Repair and Ku70/Bax-Mediated Apoptosis

Directory of Open Access Journals (Sweden)

Aman Wang

2017-05-01

Full Text Available Resistance to platinum-based chemotherapy is one of the most important reasons for treatment failure in advanced non-small cell lung cancer, but the underlying mechanism is extremely complex and unclear. The present study aimed to investigate the correlation of ubiquitin-specific peptidase 22 (USP22 with acquired resistance to cisplatin in lung adenocarcinoma. In this study, we found that overexpression of USP22 could lead to cisplatin resistance in A549 cells. USP22 and its downstream proteins γH2AX and Sirt1 levels are upregulated in the cisplatin- resistant A549/CDDP cell line. USP22 enhances DNA damage repair and induce cisplatin resistance by promoting the phosphorylation of histone H2AX via deubiquitinating histone H2A. In addition, USP22 decreases the acetylation of Ku70 by stabilizing Sirt1, thus inhibiting Bax-mediated apoptosis and inducing cisplatin resistance. The cisplatin sensitivity in cisplatin-resistant A549/CDDP cells was restored by USP22 inhibition in vivo and vitro. In summary, our findings reveal the dual mechanism of USP22 involvement in cisplatin resistance that USP22 can regulate γH2AX-mediated DNA damage repair and Ku70/Bax-mediated apoptosis. USP22 is a potential target in cisplatin-resistant lung adenocarcinoma and should be considered in future therapeutic practice.

Ecrivains français de Page classique proposés pour l'enseignement du F.LE. en Espagne aux 18e et 19e siècles

OpenAIRE

Fischer Hubert, Denise

2015-01-01

L'étude de la littérature dans les manuels de FLE est assez tardive. L'accent est surtout mis, aux 17e et 18° siècles, sur les règles de grammaire, de prononciation et aussi sur le «français fonctionnel» (dialogues utiles aux marchands et voyageurs qui se déplacent en France et ont besoin d'une phraséologie courante). A la fin du 18e et au 19e siècle, on commence à penser que la lecture des grands classiques est un point important dans l'étude de la langue. Le grammairien se réfère sans cesse...

The usefulness of dynamic O-(2-18F-fluoroethyl)-L-tyrosine PET in the clinical evaluation of brain tumors in children and adolescents

DEFF Research Database (Denmark)

Dunkl, Veronika; Cleff, Corvin; Stoffels, Gabriele

2015-01-01

UNLABELLED: Experience regarding O-(2-(18)F-fluoroethyl)-L-tyrosine ((18)F-FET) PET in children and adolescents with brain tumors is limited. METHODS: Sixty-nine (18)F-FET PET scans of 48 children and adolescents (median age, 13 y; range, 1-18 y) were analyzed retrospectively. Twenty-six scans...... to assess newly diagnosed cerebral lesions, 24 scans for diagnosing tumor progression or recurrence, 8 scans for monitoring of chemotherapy effects, and 11 scans for the detection of residual tumor after resection were obtained. Maximum and mean tumor-to-brain ratios (TBRs) were determined at 20-40 min...... after injection, and time-activity curves of (18)F-FET uptake were assigned to 3 different patterns: constant increase; peak at greater than 20-40 min after injection, followed by a plateau; and early peak (≤ 20 min), followed by a constant descent. The diagnostic accuracy of (18)F-FET PET was assessed...

Striatal kinetics of ( sup 11 C)-(+)-nomifensine and 6-( sup 18 F)fluoro-L-dopa in Parkinson's disease measured with positron emission tomography

Energy Technology Data Exchange (ETDEWEB)

Tedroff, J; Aquilonius, S -M [Department of Neurology, University Hospital (Sweden); Laihinen, A; Rinne, U [Department of Neurology, University of Turku (Finland); Hartvig, P [Department of Hospital Pharmacy, University Hospital (Sweden); Anderson, J [Department of Radiation Sciences, University Hospital (Sweden); Lundqvist, H [Svenberg Laboratory, Uppsala University (Sweden); Haaparanta, M; Solin, O [Medical Cyclotron Laboratory, University of Turku (Finland); Antoni, G; Gee, A D; Ulin, J; Laangstroem, B [Department of Organic Chemistry, University Hospital (Sweden)

1990-01-01

The kinetics in brain of the dopamine reuptake blocking agent ({sup 11}C)-(+)-nomifensine and the L-dopa analogue 6-({sup 18}F)fluoro-L-dopa were compared in 3 patients with idopathic Parkinson's disease and agematched healthy volunteers using positron emission tomography. Regional uptake was analyzed and quantified according to a 3-compartment model. Retention of both tracers in striatal regions of the parkinsonian patients were reduced compared with the healthy volunteers mainly in the putamen, while the caudate nuclleus was only mildly affected. The reductions were considerably less than the decrease previously reported postmortem for striatal dopamine content in the basal ganglia of patients with Parkinson's disease. A fairly constant ratio between 6-({sup 18}F)fluoro-L-dopa utilization and ({sup 11}C)-(+)-nomifensine binding in the caudate nucleus and the putamen were found in both groups unrelated to the size of the estimated parameters. This indicates that a limiting factor for the utilization of exogenous levodopa in Parkinsons's disease may be a reduced transport capacity for the amino acid into the dopaminergic terminals. (author).

Microfluidic preparation of [18F]FE-SUPPY and [18F]FE-SUPPY:2 - comparison with conventional radiosyntheses

International Nuclear Information System (INIS)

Ungersboeck, Johanna; Philippe, Cecile; Mien, Leonhard-Key; Haeusler, Daniela; Shanab, Karem; Lanzenberger, Rupert; Spreitzer, Helmut; Keppler, Bernhard K.; Dudczak, Robert; Kletter, Kurt; Mitterhauser, Markus; Wadsak, Wolfgang

2011-01-01

Introduction: Recently, first applications of microfluidic principles for radiosyntheses of positron emission tomography compounds were presented, but direct comparisons with conventional methods were still missing. Therefore, our aims were (1) the set-up of a microfluidic procedure for the preparation of the recently developed adenosine A 3 -receptor tracers [ 18 F]FE-SUPPY [5-(2-[ 18 F]fluoroethyl)2,4-diethyl-3-(ethylsulfanylcarbonyl) -6-phenylpyridine-5-carboxylate] and [ 18 F]FE-SUPPY:2 [5-ethyl-2,4-diethyl-3-((2-[ 18 F]fluoroethyl)sulfanylcarbonyl) -6-phenylpyridine-5-carboxylate] and (2) the direct comparison of reaction conditions and radiochemical yields of the no-carrier-added nucleophilic substitution with [ 18 F]fluoride between microfluidic and conventional methods. Methods: For the determination of optimal reaction conditions within an Advion NanoTek synthesizer, 5-50 μl of precursor and dried [ 18 F]fluoride solution were simultaneously pushed through the temperature-controlled reactor (26 o C-180 o C) with defined reactant bolus flow rates (10-50 μl/min). Radiochemical incorporation yields (RCIYs) and overall radiochemical yields for large-scale preparations were compared with data from conventional batch-mode syntheses. Results: Optimal reaction parameters for the microfluidic set-up were determined as follows: 170 o C, 30-μl/min pump rate per reactant (reaction overall flow rate of 60 μl/min) and 5-mg/ml precursor concentration in the reaction mixture. Applying these optimized conditions, we observed a significant increase in RCIY from 88.2% to 94.1% (P 18 F]FE-SUPPY and that from 42.5% to 95.5% (P 18 F]FE-SUPPY:2 using microfluidic instead of conventional heating. Precursor consumption was decreased from 7.5 and 10 mg to 1 mg per large-scale synthesis for both title compounds, respectively. Conclusion: The direct comparison of radiosyntheses data applying a conventional method and a microfluidic approach revealed a significant increase of RCIY

Carbidopa and physiological distribution of the 6-L-[{sup 18}F]-fluoro-dihydroxy-phenylalanine ({sup 18}F-DOPA); Carbidopa et biodistribution physiologique de la 6-L-[{sup 18}F]-fluorodihydroxyphenylalanine ({sup 18}F-DOPA)

Energy Technology Data Exchange (ETDEWEB)

Detour, J.; Hammer, C.; Lucas, A. [Hopitaux universitaires de Strasbourg, Service de radiopharmacie, 67 (France); Imperiale, A.; Constantinesco, A. [Hopitaux universitaires de Strasbourg, Service de biophysique et medecine nucleaire, 67 (France); Beretz, L. [Hopitaux universitaires de Strasbourg, pole de pharmacie-pharmacologie, 67 (France)

2010-07-01

Purpose: The administration of carbidopa, an peripheral inhibitor of decarboxylase DOPA, may be performed prior to a full body PET scan {sup 18}F-DOPA. There is currently no consensus regarding the routine use of this metabolic preparation (200 mg, 100 mg, 2 mg / kg, no pre-medication). Conclusions: The absence of pre-medication clearly increases pancreatic uptake of {sup 18}F-D.O.P.A.. These results suggest to reconsider the metabolic preparation based on carbidopa, particularly in cases of suspected clinico biological forms of diffuse hyper-insulinism (nesidioblastosis). Pre-medication in cases of digestive neuroendocrine tumors should be reconsidered. The dose-dependent effect of pre-medication on the tumor uptake remains to be explored. (N.C.)

Some clastic rocks as parent rocks in beech forests of Brezovica - Južni Kučaj

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Joksimović Vesna

2003-01-01

Full Text Available On the large forest areas, where the measures of soil quality improvement are absent or rarely undertaken, the rocks are the sources of a great number of elements in plant nutrition and one of the factors affecting the contents of some elements in plants. The aim of the study is to determine the differences in the contents of Cu, Zn, Mn, Ni, Fe, Cd, Co, Pb and Cr in the beech leaves developed in the same climate conditions, on morphologically similar terrains, composed of different types of sedimentary rocks. This paper presents the study results of the contents of the above elements in argillites, sandstones (grauwackes and microconglomerates occurring as the parent rocks in high beech forests in the region of GJ Bogovina (Brezovica Južni Kučaj and in the leaves of beech developed on these rocks.

Diagnosis of pseudoprogression in patients with glioblastoma using O-(2-[{sup 18}F]fluoroethyl)-l-tyrosine PET

Energy Technology Data Exchange (ETDEWEB)

Galldiks, Norbert [University of Cologne, Department of Neurology, Cologne (Germany); Forschungszentrum Juelich, Institute of Neuroscience and Medicine, Juelich (Germany); University of Cologne, Center of Integrated Oncology (CIO), Cologne (Germany); Dunkl, Veronika; Fink, Gereon R. [University of Cologne, Department of Neurology, Cologne (Germany); Forschungszentrum Juelich, Institute of Neuroscience and Medicine, Juelich (Germany); Stoffels, Gabriele [Forschungszentrum Juelich, Institute of Neuroscience and Medicine, Juelich (Germany); Hutterer, Markus; Hau, Peter [University of Regensburg, Department of Neurology and Wilhelm Sander-NeuroOncology Unit, Regensburg (Germany); Rapp, Marion; Sabel, Michael [Heinrich Heine University Duesseldorf, Department of Neurosurgery, Duesseldorf (Germany); Reifenberger, Guido [Heinrich Heine University Duesseldorf, Department of Neuropathology, Duesseldorf (Germany); Kebir, Sied [University of Bonn, Department of Neurology, Bonn (Germany); Dorn, Franziska [University of Cologne, Department of Neuroradiology, Cologne (Germany); Blau, Tobias [University of Cologne, Department of Neuropathology, Cologne (Germany); Herrlinger, Ulrich [University of Cologne, Center of Integrated Oncology (CIO), Cologne (Germany); University of Bonn, Department of Neurology, Bonn (Germany); Ruge, Maximilian I. [University of Cologne, Center of Integrated Oncology (CIO), Cologne (Germany); University of Cologne, Department of Stereotaxy and Functional Neurosurgery, Cologne (Germany); Kocher, Martin [University of Cologne, Center of Integrated Oncology (CIO), Cologne (Germany); University of Cologne, Department of Radiation Oncology, Cologne (Germany); Goldbrunner, Roland [University of Cologne, Center of Integrated Oncology (CIO), Cologne (Germany); University of Cologne, Department of Neurosurgery, Cologne (Germany); Drzezga, Alexander; Schmidt, Matthias [University of Cologne, Department of Nuclear Medicine, Cologne (Germany); Langen, Karl-Josef [Forschungszentrum Juelich, Institute of Neuroscience and Medicine, Juelich (Germany); University of Aachen, Department of Nuclear Medicine, Aachen (Germany)

2015-04-01

The follow-up of glioblastoma patients after radiochemotherapy with conventional MRI can be difficult since reactive alterations to the blood-brain barrier with contrast enhancement may mimic tumour progression (i.e. pseudoprogression, PsP). The aim of this study was to assess the clinical value of O-(2-{sup 18}F-fluoroethyl)-l-tyrosine ({sup 18}F-FET) PET in the differentiation of PsP and early tumour progression (EP) after radiochemotherapy of glioblastoma. A group of 22 glioblastoma patients with new contrast-enhancing lesions or lesions showing increased enhancement (>25 %) on standard MRI within the first 12 weeks after completion of radiochemotherapy with concomitant temozolomide (median 7 weeks) were additionally examined using amino acid PET with {sup 18}F-FET. Maximum and mean tumour-to-brain ratios (TBR{sub max}, TBR{sub mean}) were determined. {sup 18}F-FET uptake kinetic parameters (i.e. patterns of time-activity curves, TAC) were also evaluated. Classification as PsP or EP was based on the clinical course (no treatment change at least for 6 months), follow-up MR imaging and/or histopathological findings. Imaging results were also related to overall survival (OS). PsP was confirmed in 11 of the 22 patients. In patients with PsP, {sup 18}F-FET uptake was significantly lower than in patients with EP (TBR{sub max} 1.9 ± 0.4 vs. 2.8 ± 0.5, TBR{sub mean} 1.8 ± 0.2 vs. 2.3 ± 0.3; both P < 0.001) and presence of MGMT promoter methylation was significantly more frequent (P = 0.05). Furthermore, a TAC type II or III was more frequently present in patients with EP (P = 0.04). Receiver operating characteristic analysis showed that the optimal {sup 18}F-FET TBR{sub max} cut-off value for identifying PsP was 2.3 (sensitivity 100 %, specificity 91 %, accuracy 96 %, AUC 0.94 ± 0.06; P < 0.001). Univariate survival analysis showed that a TBR{sub max} <2.3 predicted a significantly longer OS (median OS 23 vs. 12 months; P = 0.046). {sup 18}F-FET PET may facilitate

Simplification of intradermal skin testing in Hymenoptera venom allergic children.

Science.gov (United States)

Cichocka-Jarosz, Ewa; Stobiecki, Marcin; Brzyski, Piotr; Rogatko, Iwona; Nittner-Marszalska, Marita; Sztefko, Krystyna; Czarnobilska, Ewa; Lis, Grzegorz; Nowak-Węgrzyn, Anna

2017-03-01

The direct comparison between children and adults with Hymenoptera venom anaphylaxis (HVA) has never been extensively reported. Severe HVA with IgE-documented mechanism is the recommendation for venom immunotherapy, regardless of age. To determine the differences in the basic diagnostic profile between children and adults with severe HVA and its practical implications. We reviewed the medical records of 91 children and 121 adults. Bee venom allergy was exposure dependent, regardless of age (P bee venom allergic group, specific IgE levels were significantly higher in children (29.5 kU A /L; interquartile range, 11.30-66.30 kU A /L) compared with adults (5.10 kU A /L; interquartile range, 2.03-8.30 kU A /L) (P venom were higher in bee venom allergic children compared with the wasp venom allergic children (P venom. At concentrations lower than 0.1 μg/mL, 16% of wasp venom allergic children and 39% of bee venom allergic children had positive intradermal test results. The median tryptase level was significantly higher in adults than in children for the entire study group (P = .002), as well as in bee (P = .002) and wasp venom allergic groups (P = .049). The basic diagnostic profile in severe HVA reactors is age dependent. Lower skin test reactivity to culprit venom in children may have practical application in starting the intradermal test procedure with higher venom concentrations. Copyright © 2016 American College of Allergy, Asthma & Immunology. Published by Elsevier Inc. All rights reserved.

18F-fluorodihydroxyphenylalanine PET/CT in pheochromocytoma and paraganglioma: relation to genotype and amino acid transport system L

International Nuclear Information System (INIS)

Feral, Chloe C.; Tissot, Floriane S.; Tosello, Lionel; Fakhry, Nicolas; Sebag, Frederic; Pacak, Karel; Taieb, David

2017-01-01

F-FDOPA is a highly sensitive and specific radiopharmaceutical for pheochromocytoma and paraganglioma (PPGL) imaging. However, 18 F-FDOPA might be falsely negative in these tumors, especially those related to mutations in succinate dehydrogenase genes (SDHx). The aim of the present study was to evaluate the relationship between expression of L-DOPA transporters and 18 F-FDOPA PET imaging results in PPGL. From 2007 to 2015, 175 patients with non-metastatic PPGL were evaluated by 18 F-FDOPA PET/CT for initial diagnosis/staging and follow-up. 18 F-FDOPA PET/CT was considered as falsely negative for at least one lesion in 10/126 (8%) patients (two sporadic, six SDHD, two SDHB PPGLs). The mRNA and protein expression levels of CD98hc and LATs were evaluated in samples with different genetic backgrounds and imaging phenotypes. The qRT-PCR and immunohistochemical analyses were performed in 14 and 16 tumor samples, respectively. The SDHx mutated samples exhibited a significant decrease in mRNA expression of LAT3 when compared to sporadic PPGLs (P = 0.042). There was also a statistical trend toward decreased CD98hc (P = 0.147) and LAT4 (P = 0.012) levels in SDHx vs sporadic PPGLs. No difference was observed for LAT1/LAT2 mRNA levels. LAT1 protein was expressed in 15 out of 16 (93.75%) SDHx tumors, regardless of the 18 F-FDOPA positivity. LAT1 and CD98hc were co-expressed in 6/8 18 F-FDOPA-negative PPGLs. In contrast, in one case with absence of LAT1/CD98hc, 18 F-FDOPA uptake was positive and attributed to LAT4 expression. We conclude that down-regulation of LAT1/CD98hc cannot explain the imaging phenotype of SDHx-related PPGLs. A reduced activity of LAT1 remains the primary hypothesis possibly due to a modification of intracellular amino acid content which may reduce 18 F-FDOPA uptake. (orig.)

The C-Terminal Domain of Cernunnos/XLF Is Dispensable for DNA Repair In Vivo▿ †

Science.gov (United States)

Malivert, Laurent; Callebaut, Isabelle; Rivera-Munoz, Paola; Fischer, Alain; Mornon, Jean-Paul; Revy, Patrick; de Villartay, Jean-Pierre

2009-01-01

The core nonhomologous end-joining DNA repair pathway is composed of seven factors: Ku70, Ku80, DNA-PKcs, Artemis, XRCC4 (X4), DNA ligase IV (L4), and Cernunnos/XLF (Cernunnos). Although Cernunnos and X4 are structurally related and participate in the same complex together with L4, they have distinct functions during DNA repair. L4 relies on X4 but not on Cernunnos for its stability, and L4 is required for optimal interaction of Cernunnos with X4. We demonstrate here, using in vitro-generated Cernunnos mutants and a series of functional assays in vivo, that the C-terminal region of Cernunnos is dispensable for its activity during DNA repair. PMID:19103754

Whole-body kinetics and dosimetry of cis-4-[{sup 18}F]fluoro-l-proline

Energy Technology Data Exchange (ETDEWEB)

Boerner, Anne R.; Langen, Karl-J. E-mail: k.j.langen@fz-juelich.de; Herzog, Hans; Hamacher, Kurt; Mueller-Mattheis, Volker; Schmitz, Thomas; Ackermann, Rolf; Coenen, Heinz H

2001-04-01

The whole-body distribution of 4-cis[{sup 18}F]fluoro-L-proline (cis-FPro) was studied in six patients with urological tumors by PET. Based on the IMEDOSE and MIRDOSE procedures radiation absorbed doses were estimated from whole-body PET scans acquired at 1 and 3-5 h after i.v. injection of 400 MBq cis-FPro. Cis-FPro showed high retention in the renal cortex and a slight uptake in liver and pancreas. Urinary excretion ranged from 12 to 19% at 5 h p.i. Highest absorbed doses were found for the urinary bladder wall and the kidneys (44.1/44.0 {mu}Gy/MBq). The effective dose according to ICRP 60 was 15.1 {mu}Sv/MBq for adults. This leads to an effective dose of 6.0 mSv in a PET study using 400 MBq cis-FPro.

In-vivo studies by positron emission tomography of the pharmacokinetics of L-6-F-18-fluorodopa

International Nuclear Information System (INIS)

Pate, B.D.; Calne, D.B.; Hewitt, K.A.; Ruth, T.J.; Adam, M.J.

1989-01-01

Positron emission tomography has been used to study the pharmacokinetics of fluorine-18-labelled L-6-fluorodopa in the brains of cynomolgus monkey subjects. The protocol for each experiment consisted of two series of twelve 10-minutes scans, conducted one after the other with the monkey in the same position, with an inhibitor acting at a specific stage of the kinetics, administered before the second series. Subtractions of the two scan series (following correction for activity residue in the second scans) then gave a quantitative measure of the effects produced by the inhibitor. The inhibitors studied include NSD 1015 (decarboxylase inhibitor), chlorgyline (MAO-A inhibitor), deprenyl (MAO-B inhibitor), pargyline (inhibitor of both MAO-A and MAO-B), U-0521 (COMT inhibitor), and reserpine (vesicular storage inhibitor). The results show that L-6-fluorodopa is a substrate for dopa decarboxylase, while fluorodopamine is a substrate for both MAO-A and MAO-B, and for COMT. Vesicular storage (inhibited by reserpine) was shown also to be essential for concentration of the activity into striatal images

Motorické projevy laterality u osob středního věku a starších

OpenAIRE

Habartová, Lucie

2008-01-01

Název dielomové eráce: Motorické projevy laterality u osob středního věku a starších. Název v gnglickém jazyce: The Manifestations of Motoric Laterality of Middle-aged People and Elderly. Cíle eráce: Definovat, popsat lateralitu, zjistit stupeň laterality horní končetiny, dolní končetiny a oka. Zjistit vztah laterality horních končetin a očí, horních končetin a dolních končetin. Metoda: Lateralitu budeme zjišťovat na základě dotazníků a motorických testů. Testovaný soubor čítá 50 probandů ve ...

Positron-labeled antioxidant 6-deoxy-6-[{sup 18}F]fluoro-L-ascorbic acid: Increased uptake in transient global ischemic rat brain

Energy Technology Data Exchange (ETDEWEB)

Yamamoto, Fumihiko; Shibata, Shigenobu; Watanabe, Shigenori; Masuda, Kouji; Maeda, Minoru

1996-05-01

The in vivo uptake and distribution of 6-deoxy-6-[{sup 18}F]fluoro-L-ascorbic acid ({sup 18}F-DFA) were investigated in rat brains following postischemic reperfusion. Global cerebral ischemia was induced in male Wistar rats for 20 min by occlusion of four major arteries. Two time points were chosen for {sup 18}F-DFA injection to rats subjected to cerebral ischemia, at the start of recirculation and 5 days following recirculation. The rats were then killed at 2 h after tail-vein administration of {sup 18}F-DFA and tissue radioactivity concentration was determined. Increased uptake of radioactivity in particular brain regions, including the cerebral cortex, hypothalamus, and amygdala following injection of {sup 18}F-DFA, compared to the sham-operated control, was observed 5 days after reperfusion. Similar results were also obtained in in vitro experiments using brain slices. Abnormal in vivo accumulation of {sup 45}Ca, a marker of regional postischemic injury, was observed in these brain regions in tissue dissection experiments. Furthermore, metabolite analysis of nonradioactive DFA using {sup 19}F-NMR showed that DFA remained intact in the postischemic reperfusion brain. The present results indicate that {sup 18}F-DFA increasingly accumulates in damaged regions of postischemic reperfusion brain.

SERANGAN BENALU PADA BEBERAPA KELAS UMUR TANAMAN JATI DI WILAYAH HUTAN BKPH BEGAL, KPH NGAWI, JAWA TIMUR (An Attact of Parasitic Plant on Several Ages of Teak Plantation In Begal Forest Sub-District, Ngawi Forest District, East Java

Directory of Open Access Journals (Sweden)

Soewarno Hasanbahri

2014-10-01

The objectives of the study were to determine the relationship of teak plantation age class with the frequency and severity of teak trees due to an attack of parasitic plant (mistletoe, and parasitic plant distribution patterns horizontally. The sampling method in this study was the Multistage Sampling, i.e. at each age group classe (KU represented one compartment and each compartment made an individual sampling tree as much as 10 % for KU V and up (old age classes, 5 % for KU III – IV (middle age classes and 1 % for KU I - II (young age classes to the total trees populations. Age class relationship with the frequency and degree of tree damage due to an attack of parasitic plant were analyzed by correlation test formula and for the parasitic plant distribution were analysed by the Poisson distribution formula and the Binomial Test Statistically Reversed. The conclusions of this study that were found two species of parasitic plants of Dendrophthoe pentandra and Scurula parasitiaca of the Loranthaceae family members, sub-family Viscoidae. The frequency of teak trees that were attacted by parasitic plants ranged from 12.88 % for KU II and  followed by 15.55 % for KU I, 15.72 % for KU V, 18.06 % for KU IV and VI, up  to 19.73 % for KU III. The correlation between an attack of parasitic plants and the teak forest age classes have proven that significant relationship to the level of the proximal health. In another part, proved that age class does not have a significant relationship to the distal extent of damage. Nevertheless , the teak tree damage suffered an attack of parasitic plants were more prevalent on trees in the younger age classes. It was shown by a comparison of proximal and distal branches in each age class, namely: -23.81 cm for KU I, -1.56 cm for KU II, 14.66 cm for KU III, 24.13 cm for KU IV, 22.40 cm for KU V and 54.94 cm for KU VI. With the loss of future growth faced by teak trees in the young age classes become very vulnerable in the presence of

Effects of the equatorial ionosphere on L-band Earth-space transmissions

Science.gov (United States)

Smith, Ernest K.; Flock, Warren L.

1993-01-01

Ionosphere scintillation can effect satellite telecommunication up to Ku-band. Nighttime scintillation can be attributed to large-scale inhomogeneity in the F-region of the ionosphere predominantly between heights of 200 and 600 km. Daytime scintillation has been attributed to sporadic E. It can be thought of as occurring in three belts: equatorial, high-latitude, and mid-latitude, in order of severity. Equatorial scintillation occurs between magnetic latitudes +/- 25 degrees, peaking near +/- 10 degrees. It commonly starts abruptly near 2000 local time and dies out shortly after midnight. There is a strong solar cycle dependence and a seasonal preference for the equinoxes, particularly the vernal one. Equatorial scintillation occurs more frequently on magnetically quiet than on magnetically disturbed days in most longitudes. At the peak of the sunspot cycle scintillation depths as great as 20 dB were observed at L-band.

A Small Ku-Band Polarization Tracking Active Phased Array for Mobile Satellite Communications

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Wei Shi

2013-01-01

Full Text Available A compact polarization tracking active phased array for Ku-band mobile satellite signal reception is presented. In contrast with conventional mechanically tracking antennas, the approach presented here meets the requirements of beam tracking and polarization tracking simultaneously without any servo components. The two-layer stacked square patch fed by two probes is used as antenna element. The impedance bandwidth of 16% for the element covers the operating frequency range from 12.25 GHz to 12.75 GHz. In the presence of mutual coupling, the dimensional parameters for each element of the small 7 × 7 array are optimized during beam scanning and polarization tracking. The compact polarization tracking modules based on the low-temperature cofired ceramic (LTCC system-in-package (SiP technology are proposed. A small active phased array prototype with the size of 120 mm (length × 120 mm (width × 55 mm (height is developed. The measured polarization tracking patterns of the prototype are given. The polarization tracking beam can be steered in the elevation up to 50°. The gain of no less than 16.0 dBi and the aperture efficiency of more than 50% are obtained. The measured and simulated polarization tracking patterns agreed well.

Efficient gene replacements in ku70 disruption strain of Aspergillus chevalieri var. intermedius

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Qingqing Huang

2017-01-01

Full Text Available Aspergillus chevalieri var. intermedius is a dominant filamentous fungal species in Fuzhuan tea and is associated with the quality and health benefits of this tea. The sexual or asexual reproduction of this fungus depends on the osmotic pressure of the tea. Efforts to enhance the beneficial effects of A. chevalieri var. intermedius are hampered by difficulties in disrupting its genes. To address this issue, we identified the A. chevalieri var. intermedius homolog (Acku70 of human Ku70 and generated an Acku70 disruption strain (ΔAcku70, aiming to improve the gene replacement efficiency. ΔAcku70 grew at a slightly lower rate in vitro than the wild-type strain; however, the two strains exhibited similar sensitivity to temperature, osmotic pressure and the effects of ethyl methane sulphonate and H2O2. The replacement efficiency of veA and flbA dramatically increased in ΔAcku70 compared to that in the wild type. The efficiency of flbA replacement increased from 2.6% to 80%, whereas the frequency of veA disruption increased from 15.2% to 83.9% and from 30.8% to 86.8%. Thus, ΔAcku70 is suitable for use as a type strain for large-scale functional genomic analysis of A. chevalieri var. intermedius.

Comparison of 18F-fluoro-L-DOPA, 18F-fluoro-deoxyglucose, and 18F-fluorodopamine PET and 123I-MIBG scintigraphy in the localization of pheochromocytoma and paraganglioma.

NARCIS (Netherlands)

Timmers, H.J.L.M.; Chen, C.C.; Carrasquillo, J.A.; Whatley, M.; Ling, A.; Havekes, B.; Eisenhofer, G.; Martiniova, L.; Adams, K.T.; Pacak, K.

2009-01-01

CONTEXT: Besides (123)I-metaiodobenzylguanidine (MIBG), positron emission tomography (PET) agents are available for the localization of paraganglioma (PGL), including (18)F-3,4-dihydroxyphenylalanine (DOPA), (18)F-fluoro-2-deoxy-D-glucose ((18)F-FDG), and (18)F-fluorodopamine ((18)F-FDA). OBJECTIVE:

Microfluidic preparation of [{sup 18}F]FE-SUPPY and [{sup 18}F]FE-SUPPY:2 - comparison with conventional radiosyntheses

Energy Technology Data Exchange (ETDEWEB)

Ungersboeck, Johanna [Department of Nuclear Medicine, Medical University of Vienna, A-1090 Vienna (Austria); Department of Inorganic Chemistry, University of Vienna, A-1090 Vienna (Austria); Philippe, Cecile [Department of Nuclear Medicine, Medical University of Vienna, A-1090 Vienna (Austria); Department of Pharmaceutical Technology and Biopharmaceutics, University of Vienna, A-1090 Vienna (Austria); Mien, Leonhard-Key [Department of Nuclear Medicine, Medical University of Vienna, A-1090 Vienna (Austria); Haeusler, Daniela [Department of Nuclear Medicine, Medical University of Vienna, A-1090 Vienna (Austria); Department of Pharmaceutical Technology and Biopharmaceutics, University of Vienna, A-1090 Vienna (Austria); Shanab, Karem [Department of Nuclear Medicine, Medical University of Vienna, A-1090 Vienna (Austria); Department of Drug and Natural Product Synthesis, University of Vienna, A-1090 Vienna (Austria); Lanzenberger, Rupert [Department of Psychiatry and Psychotherapy, Medical University of Vienna, A-1090 Vienna (Austria); Spreitzer, Helmut [Department of Drug and Natural Product Synthesis, University of Vienna, A-1090 Vienna (Austria); Keppler, Bernhard K. [Department of Inorganic Chemistry, University of Vienna, A-1090 Vienna (Austria); Dudczak, Robert; Kletter, Kurt [Department of Nuclear Medicine, Medical University of Vienna, A-1090 Vienna (Austria); Mitterhauser, Markus [Department of Nuclear Medicine, Medical University of Vienna, A-1090 Vienna (Austria); Department of Pharmaceutical Technology and Biopharmaceutics, University of Vienna, A-1090 Vienna (Austria); Hospital Pharmacy, General Hospital of Vienna, A-1090 Vienna (Austria); Wadsak, Wolfgang, E-mail: wolfgang.wadsak@meduniwien.ac.a [Department of Nuclear Medicine, Medical University of Vienna, A-1090 Vienna (Austria); Department of Inorganic Chemistry, University of Vienna, A-1090 Vienna (Austria)

2011-04-15

Introduction: Recently, first applications of microfluidic principles for radiosyntheses of positron emission tomography compounds were presented, but direct comparisons with conventional methods were still missing. Therefore, our aims were (1) the set-up of a microfluidic procedure for the preparation of the recently developed adenosine A{sub 3}-receptor tracers [{sup 18}F]FE-SUPPY [5-(2-[{sup 18}F]fluoroethyl)2,4-diethyl-3-(ethylsulfanylcarbonyl) -6-phenylpyridine-5-carboxylate] and [{sup 18}F]FE-SUPPY:2 [5-ethyl-2,4-diethyl-3-((2-[{sup 18}F]fluoroethyl)sulfanylcarbonyl) -6-phenylpyridine-5-carboxylate] and (2) the direct comparison of reaction conditions and radiochemical yields of the no-carrier-added nucleophilic substitution with [{sup 18}F]fluoride between microfluidic and conventional methods. Methods: For the determination of optimal reaction conditions within an Advion NanoTek synthesizer, 5-50 {mu}l of precursor and dried [{sup 18}F]fluoride solution were simultaneously pushed through the temperature-controlled reactor (26{sup o}C-180{sup o}C) with defined reactant bolus flow rates (10-50 {mu}l/min). Radiochemical incorporation yields (RCIYs) and overall radiochemical yields for large-scale preparations were compared with data from conventional batch-mode syntheses. Results: Optimal reaction parameters for the microfluidic set-up were determined as follows: 170{sup o}C, 30-{mu}l/min pump rate per reactant (reaction overall flow rate of 60 {mu}l/min) and 5-mg/ml precursor concentration in the reaction mixture. Applying these optimized conditions, we observed a significant increase in RCIY from 88.2% to 94.1% (P<.0001, n{>=}11) for [{sup 18}F]FE-SUPPY and that from 42.5% to 95.5% (P<.0001, n{>=}5) for [{sup 18}F]FE-SUPPY:2 using microfluidic instead of conventional heating. Precursor consumption was decreased from 7.5 and 10 mg to 1 mg per large-scale synthesis for both title compounds, respectively. Conclusion: The direct comparison of radiosyntheses data

Pusaudžu agresivitātes saistība ar vecāku audzināšanas stilu.

OpenAIRE

Dambe, Agnese

2007-01-01

Šajā darbā tiek apskatīta viena no mūsdienu būtiskākajām problēmām- pusaudžu agresivitāte. Pētījuma mērķis bija noskaidrot, vai pastāv statistiski nozīmīgas saistības starp vecāku audzināšanas stilu un pusaudžu agresivitāti. Pētījuma izlasi veido 60 pusaudži (30 jaunietes un 30 jaunieši) no pilnām ģimenēm, vecumposmā no 15-17 gadiem. Pētījumā tika izmantotas divas pētījuma metodes- A.H. Bassa (A.H. Buss)- A. Darki (A. Durkee) aptaujas anketa agresīvu reakciju noteikšanai un ...

Radiosynthesis of F-18 labeled cytidine analog 2'-fluoro-5-iodo-l-{beta}-D-arabinofuranosylcytosine ([{sup 18}F]FIAC)

Energy Technology Data Exchange (ETDEWEB)

Wu, C.-Y.; Chan, P.-C.; Chang, W.-T. [Institute of Biomedical Imaging and Radiological Sciences, National Yang-Ming University, 155, Li-Nong Street, Sector 2, Bei-tou, Taipei 112, Taiwan (China); Liu, R.-S. [Department of Nuclear Medicine, Faculty of Medicine, National Yang-Ming University, Taiwan (China); Department of Nuclear Medicine and National PET/Cyclotron Center, Taipei Veterans General Hospital, Taiwan (China); Alauddin, Mian M. [Department of Experimental Diagnostic Imagiing, MD Anderson Cancer Center, University of Texas (United States); Wang, H-E. [Institute of Biomedical Imaging and Radiological Sciences, National Yang-Ming University, 155, Li-Nong Street, Sector 2, Bei-tou, Taipei 112, Taiwan (China)], E-mail: hewang@ym.edu.tw

2009-07-15

We reported the synthesis of 2'-deoxy-2'-[{sup 18}F]fluoro-5-iodo-1-{beta}-D-arabinofuranosyl-5-iodo-cytosine ([{sup 18}F]FIAC) with 15-20% radiochemical yield (decay corrected) in 3.5 h. 2-deoxy-2-[{sup 18}F]fluoro-1,3,5-tri-O-benzoyl-{alpha}-D-arabinofuranose was prepared following literature procedures with some modifications (yield>70%). The {sup 18}F-fluorosugar was converted to 1-bromo-{sup 18}F-fluorosugar, and then coupled with 5-iodocytocine silyl ether. A mixture of acetonitrile (ACN) and 1,2-dichloroethane (DCE) were employed to achieve optimum radiochemical yield and acceptable {beta}-anomer selectivity ({alpha}/{beta}=1/3). After hydrolyzed with sodium methoxide, the crude product was purified using HPLC to afford the {beta}-[{sup 18}F]FIAC with high radiochemical purity ({>=}98%)

Rozbor morfologie nohy u chlapců a dívek ve věku Infans 2 a Juvenis Analysis of morphology of foot in Moravian male and female students in the age Infans 2 and Juvenis

Directory of Open Access Journals (Sweden)

Michaela Peštuková

2005-02-01

Full Text Available U 106 studentů a 162 studentek z Gymnázia ve Šternberku a Střední integrované školy v Ostravě ve věku 12–18 let byl sledován morfologický typ nohy, index nohy pro hodnocení podélné klenby nožní, vyosení palce a malíku, úhel paty a stav svalstva dolních končetin. U chlapců i dívek byla nalezena výrazně vyšší frekvence výskytu nohy egyptské (71,69 % a 70,99 %. Noha kvadratická se vyskytovala u chlapců ve velmi nízkém procentu (2,83 % s určitou individuální asymetrií, u dívek nalezena nebyla. Diagnostika plochonoží metodou Chippauxe–Šmiřáka poskytla velmi příznivé výsledky (4,94–10,38 % výskytu ploché nohy, metoda podle Szritera–Godunova naopak nález podstatně horší (38,2–43,21 % výskytu ploché nohy. S nulovým stavem vyosení palce jsme se setkali u necelé čtvrtiny souborů. U souboru chlapců byla četnost projevu valgozity a varozity palce téměř vyrovnána, věcně převažovalo varózní postavení palce vpravo. U souboru dívek dominovalo signifikantně valgózní postavení. Průměrné hodnoty se pohybovaly v rozmezí 4 až 7 stupňů. Průměrná hodnota úhlu malíku, charakterizující vbočený malík, byla vysoká (17,73 až 21,90 stupně. Průměrný úhel paty byl diagnostikován v rozmezí 15 až 18 stupňů. Při hodnocení vztahů mezi zkrácením svalů dolní končetiny a poruchami funkčního stavu klenby nožní (pouze u mužů jsme nalezli potvrzení statistické významnosti závislosti u vyosení paty a zkrácení m. triceps surae sin. a signifikantní závislost mezi úhlem paty a zkrácením flexorů kolen sin. Morphological foot type, foot index for longitudinal foot vault, misalignment of the big and little toes, heel angle and lower limb muscles condition were monitored in 106 male students and 162 female students from the Gymnasium school in Šternberk and the Integrated secondary school in Ostrava ranging in age from 12 to 18 years. A considerably

Contribution to the study of isotopic exchange of oxygen between nickel oxide and the gases arising from the oxidation reaction of carbon monoxide; Contribution a l'etude de l'echange isotopique de l'oxygene entre l'oxyde de nickel et les gaz de la reaction d'oxydation de l'oxyde de carbone

Energy Technology Data Exchange (ETDEWEB)

Bailly, J C [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

1967-12-01

The 3 isotopic reactions of oxygen: C{sup 18}O + Ni{sup 16}O {r_reversible} C{sup 16}O + Ni{sup 18}O, {sup 16}O{sup 18}O + Ni{sup 16}O {r_reversible} {sup 16}O{sub 2} + Ni{sup 18}O, and C{sup 16}O{sup 18}O + Ni{sup 16}O {r_reversible} C{sup 16}O{sub 2} + Ni{sup 18}O between CO, CO{sub 2}, O{sub 2} and NiO are studied using a mass spectrometer. The isotopic gaseous mixtures are prepared from oxygen-18 enriched water. A first order kinetic law has been found for these reactions in the gaseous phase, and the activation energies have been determined. Only CO and CO{sub 2} exchange oxygen, at room temperature, but only with part of the oxide surface. Gaseous O{sub 2} reacts with the whole surface at 250 C, the slow step of the exchange process, in the gaseous phase, being certainly the mobility of oxygen ions on the surface of NiO. (author) [French] Les 3 reactions d'echange isotopique de l'oxygene: C{sup 18}O + Ni{sup 16}O {r_reversible} C{sup 16}O + Ni{sup 18}O, {sup 16}O{sup 18}O + Ni{sup 16}O {r_reversible} {sup 16}O{sub 2} + Ni{sup 18}O, et C{sup 16}O{sup 18}O + Ni{sup 16}O {r_reversible} C{sup 16}O{sub 2} + Ni{sup 18}O entre l'oxyde de carbone, l'oxygene gazeux, le gaz carbonique et l'oxyde de nickel sont etudiees par spectrometrie de masse. Les melanges isotopiques gazeux sont prepares a partir d'une eau enrichie en isotope 18 de l'oxygene. Une loi cinetique du premier ordre a ete trouvee pour les trois reactions d'echange en phase gazeuse, et des energies d'activation de ces reactions ont ete determinees. Seuls CO et CO{sub 2} echangent l'oxygene, des la temperature ambiante, mais avec une fraction seulement de la surface de l'oxyde. O{sub 2} gazeux reagit avec toute la surface du solide a 250 C, l'etape lente du processus d'echange en phase gazeuse etant vraisemblablement liee a la mobilite des ions oxygene superficiels de NiO. (auteur)

Hypoxia imaging of uterine cervix carcinoma with (18)F-FETNIM PET/CT.

Science.gov (United States)

Vercellino, Laetitia; Groheux, David; Thoury, Anne; Delord, Marc; Schlageter, Marie-Hélène; Delpech, Yann; Barré, Emmanuelle; Baruch-Hennequin, Valérie; Tylski, Perrine; Homyrda, Laurence; Walker, Francine; Barranger, Emmanuel; Hindié, Elif

2012-11-01

Our aims were to assess the feasibility of imaging hypoxia in cervical carcinoma with (18)F-fluoroerythronitroimidazole ((18)F-FETNIM) and to compare (18)F-FETNIM uptake with metabolic uptake of (18)F-FDG. We included 16 patients with cervical carcinoma. After imaging with FDG, (18)F-FETNIM PET/CT was performed and tumor-to-muscle (T/M) ratio uptake was assessed. (18)F- FETNIM uptake was correlated to FDG uptake and osteopontin (OPN), a marker of hypoxia, and patients' outcomes. All tumors were detected by (18)F-FDG PET. (18)F-FETNIM T/M ratios ranged from 1.3 to 5.4. There was no significant correlation between (18)F-FETNIM and (18)F-FDG uptake. High (18)F-FETNIM uptake (T/M > 3.2) was associated with reduced progression-free survival (log-rank = 0.002) and overall survival (log-rank = 0.02). Osteopontin ranged from 39 to 662 μg/L (median, 102.5 μg/L). Patients with OPN greater than 144 μg/L had reduced progression-free survival compared with those with OPN less than 144 μg/L (log-rank = 0.03). We found no significant correlation between (18)F-FETNIM uptake and OPN blood levels. Our preliminary results showed that a high uptake of (18)F-FETNIM was associated with a worse progression-free and overall survival.

{sup 18}F-fluorodihydroxyphenylalanine PET/CT in pheochromocytoma and paraganglioma: relation to genotype and amino acid transport system L

Energy Technology Data Exchange (ETDEWEB)

Feral, Chloe C.; Tissot, Floriane S.; Tosello, Lionel [INSERM U1081, Institute for Research on Cancer and Aging of Nice (IRCAN), Nice (France); Fakhry, Nicolas [Aix-Marseille University, Department of Otorhinolaryngology-Head and Neck Surgery, Conception Hospital, Marseille (France); Sebag, Frederic [Aix-Marseille University, Department of Endocrine Surgery, Conception Hospital, Marseille (France); Pacak, Karel [Section on Medical Neuroendocrinology, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD (United States); Taieb, David [Aix-Marseille University, Department of Nuclear Medicine, La Timone University Hospital, CERIMED, Marseille (France)

2017-05-15

F-FDOPA is a highly sensitive and specific radiopharmaceutical for pheochromocytoma and paraganglioma (PPGL) imaging. However, {sup 18}F-FDOPA might be falsely negative in these tumors, especially those related to mutations in succinate dehydrogenase genes (SDHx). The aim of the present study was to evaluate the relationship between expression of L-DOPA transporters and {sup 18}F-FDOPA PET imaging results in PPGL. From 2007 to 2015, 175 patients with non-metastatic PPGL were evaluated by {sup 18}F-FDOPA PET/CT for initial diagnosis/staging and follow-up. {sup 18}F-FDOPA PET/CT was considered as falsely negative for at least one lesion in 10/126 (8%) patients (two sporadic, six SDHD, two SDHB PPGLs). The mRNA and protein expression levels of CD98hc and LATs were evaluated in samples with different genetic backgrounds and imaging phenotypes. The qRT-PCR and immunohistochemical analyses were performed in 14 and 16 tumor samples, respectively. The SDHx mutated samples exhibited a significant decrease in mRNA expression of LAT3 when compared to sporadic PPGLs (P = 0.042). There was also a statistical trend toward decreased CD98hc (P = 0.147) and LAT4 (P = 0.012) levels in SDHx vs sporadic PPGLs. No difference was observed for LAT1/LAT2 mRNA levels. LAT1 protein was expressed in 15 out of 16 (93.75%) SDHx tumors, regardless of the {sup 18}F-FDOPA positivity. LAT1 and CD98hc were co-expressed in 6/8 {sup 18}F-FDOPA-negative PPGLs. In contrast, in one case with absence of LAT1/CD98hc, {sup 18}F-FDOPA uptake was positive and attributed to LAT4 expression. We conclude that down-regulation of LAT1/CD98hc cannot explain the imaging phenotype of SDHx-related PPGLs. A reduced activity of LAT1 remains the primary hypothesis possibly due to a modification of intracellular amino acid content which may reduce {sup 18}F-FDOPA uptake. (orig.)

Diagnostic utility of PET/CT with {sup 18}F-DOPA and {sup 18}F-FDG in persistent or recurrent medullary thyroid carcinoma: the importance of calcitonin and carcinoembryonic antigen cutoff

Energy Technology Data Exchange (ETDEWEB)

Romero-Lluch, Ana Reyes; Guerrero-Vazquez, Raquel; Martinez-Ortega, Antonio Jesus; Navarro-Gonzalez, Elena [Hospital Universitario Virgen del Rocio, Unidad de Gestion Clinica de Endocrinologia y Nutricion, Seville (Spain); Cuenca-Cuenca, Juan Ignacio; Tirado-Hospital, Juan Luis; Borrego-Dorado, Isabel [Hospital Universitario Virgen del Rocio, Unidad de Medicina Nuclear, Seville (Spain)

2017-11-15

This study sought to evaluate and compare the utility of 18-F-fluorodihydroxyphenylalanine ({sup 18}F-DOPA) and 18-F-fluorodeoxyglucose ({sup 18}F-FDG) positron emission tomography/computed tomography (PET/CT) for identification of lesions in patients with recurrent medullary thyroid carcinoma (MTC). In addition, we analyzed the correlation between the calcitonin (Ct), carcinoembryonic antigen (CEA) levels, each doubling time (DT), and PET positivity. We evaluated the reliability of the 150 pg/mL Ct cutoff set by the American Thyroid Association guidelines for further imaging (including {sup 18}F-DOPA PET/CT). We prospectively recruited 18 patients with recurrent MTC, identified by elevation of Ct or CEA. Each patient underwent a {sup 18}F-FDG PET/CT and a {sup 18}F-DOPA PET/CT. Abnormal uptakes were detected with {sup 18}F-DOPA (n=12) and {sup 18}F-FDG (n=9), (sensitivity of 66.7% vs. 50%; p<0.01). Twenty-eight lesions were detected with {sup 18}F-DOPA vs. 16 lesions with {sup 18}F-FDG (1.56±1.5 vs. 0.89±1.18 lesions per patient; p=0.01). None of our patients showed additional lesions with {sup 18}F-FDG in comparison to {sup 18}F-DOPA. Patient-based detection rate increased significantly with Ct levels ≥150 pg/mL vs. Ct<150 pg/mL for both {sup 18}F-DOPA (sensitivity 90.9% vs. 28.6%; p=0.013) and {sup 18}F-FDG PET/CT (sensitivity 72.7% vs. 14.3%; p=0.025). Using a CEA cutoff of ≥5 ng/mL, detection rates of {sup 18}F-DOPA and {sup 18}F-FDG PET/CT were 81.1% and 72.7%, respectively. No correlation between Ct-DT or CEA-DT and PET positivity was found. Histological confirmation was obtained in eight patients. {sup 18}F-DOPA PET/CT appears to be superior to {sup 18}F-FDG PET/CT in detecting and locating lesions in patients with recurrent MTC. This technique tends to be especially useful in patients with negative results in other imaging modalities and Ct≥150 pg/mL or CEA≥5 ng/mL. (orig.)

Uptake of 18F-DCFPyL in Paget's Disease of Bone, an Important Potential Pitfall in Clinical Interpretation of PSMA PET Studies.

Science.gov (United States)

Rowe, Steven P; Deville, Curtiland; Paller, Channing; Cho, Steve Y; Fishman, Elliot K; Pomper, Martin G; Ross, Ashley E; Gorin, Michael A

2015-12-01

Prostate-specific membrane antigen (PSMA)-targeted PET imaging is an emerging technique for evaluating patients with prostate cancer (PCa) in a variety of clinical contexts. As with any new imaging modality, there are interpretive pitfalls that are beginning to be recognized. In this image report, we describe the findings in a 63-year-old male with biochemically recurrent PCa after radical prostatectomy who was imaged with 18 F-DCFPyL, a small molecule inhibitor of PSMA. Diffuse radiotracer uptake was noted throughout the sacrum, corresponding to imaging findings on contrast-enhanced CT, bone scan, and pelvic MRI consistent with Paget's disease of bone. The uptake of 18 F-DCFPyL in Paget's disease is most likely due to hyperemia and increased radiotracer delivery. In light of the overlap in patients affected by PCa and Paget's, it is important for nuclear medicine physicians and radiologists interpreting PSMA PET/CT scans to be aware of the potential for this diagnostic pitfall. Correlation to findings on conventional imaging such as diagnostic CT and bone scan can help confirm the diagnosis.

BACTERIAL ADHESION TO DENTAL AMALGAM AND 3 RESIN COMPOSITES

NARCIS (Netherlands)

SULJAK, JP; REID, G; WOOD, SM; MCCONNELL, RJ; VANDERMEI, HC; BUSSCHER, HJ

Objectives: The ability of three oral bacteria to adhere to hydrophobic amalgam (water contact angle 60 degrees) and hydrophobic resin composites (Prisma-AP.H 56 degrees, Herculite XRV 82 degrees and Z100 89 degrees) was compared using an in vitro assay. Methods and results: Following preincubation

Monitoring of Radiochemotherapy in Patients with Glioblastoma Using O-(2-[18F]Fluoroethyl-L-Tyrosine Positron Emission Tomography: Is Dynamic Imaging Helpful?

Directory of Open Access Journals (Sweden)

Marc D. Piroth

2013-09-01

Full Text Available Monitoring of radiochemotherapy (RCX in patients with glioblastoma is difficult because unspecific alterations in magnetic resonance imaging with contrast enhancement can mimic tumor progression. Changes in tumor to brain ratios (TBRs in positron emission tomography (PET using O-(2-[18F]fluoroethyl-L-tyrosine (18F-FET after RCX with temozolomide of patients with glioblastoma have been shown to be valuable parameters to predict survival. The kinetic behavior of 18F-FET in the tumors is another promising parameter to analyze tumor metabolism. In this study, we investigated the predictive value of dynamic 18F-FET PET during RCX of glioblastoma. Time-activity curves (TACs of 18F-FET uptake of 25 patients with glioblastoma were evaluated after surgery (FET-1, early (7–10 days after completion of RCX (FET-2, and 6 to 8 weeks later (FET-3. Changes in the time to peak (TTP and the slope of the TAC (10–50 minutes postinjection were analyzed and related to survival. Changes in kinetic parameters of 18F-FET uptake after RCX showed no relationship with survival time. In contrast, the high predictive value of changes of TBR to predict survival was confirmed. We conclude that dynamic 18F-FET PET does not provide additional prognostic information during RCX. Static 18F-FET PET imaging (20–40 minutes postinjection appears to be sufficient for this purpose and reduces costs.

Synthesis and Preliminary Evaluation of 5-[18F]fluoroleucine.

Science.gov (United States)

Chin, Bennett B; McDougald, Darryl; Weitzel, Douglas H; Hawk, Thomas; Reiman, Robert E; Zalutsky, Michael R; Vaidyanathan, Ganesan

2017-01-01

Amino acid transporters, such as LAT1, are overexpressed in aggressive prostate and breast carcinomas, directly influencing pathways of growth and proliferation. The purpose of this study was to synthesize and characterize a novel 18F labeled leucine analog, 5-[18F]fluoroleucine, as a potential imaging agent for aggressive tumors which may not be amenable to imaging by FDG PET. 5-fluoroleucine was synthesized and characterized, and its 18F-labeled analog was synthesized from a mesylate precursor. First, breast cancer cell line assays were performed to evaluate uptake of 3H- or 14C-labeled L-leucine and other essential amino acids. Both L-leucine and 5- [18F]fluoroleucine were tested for uptake and accumulation over time, and for uptake via LAT1. Biodistribution studies were performed to estimate radiation dosimetry for human studies. Small animal PET / CT studies of a breast cancer were performed to evaluate in vivo 5-[18F]fluoroleucine tumor uptake. Breast cancer cell lines showed increasing high net accumulation of L-[14C]leucine. Both L-leucine and 5-[18F]fluoroleucine showed increasing uptake over time in in vitro tumor cell assays, and uptake was also shown to occur via LAT1. The biodistribution study of 5-[18F]fluoroleucine showed rapid renal excretion, no significant in vivo metabolism, and acceptable dosimetry for use in humans. In vivo small animal PET / CT imaging of a breast cancer xenograft showed uptake of 5- [18F]fluoroleucine in the tumor, which progressively increased over time. 5-[18F]fluoroleucine is a leucine analog which may be useful in identifying tumors with high or upregulated expression of amino acid transporters, providing additional information that may not be provided by FDG PET. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

Self-Assembly, Supramolecular Organization, and Phase Behavior of L-Alanine Alkyl Esters (n = 9-18) and Characterization of Equimolar L-Alanine Lauryl Ester/Lauryl Sulfate Catanionic Complex.

Science.gov (United States)

Sivaramakrishna, D; Swamy, Musti J

2015-09-08

A homologous series of l-alanine alkyl ester hydrochlorides (AEs) bearing 9-18 C atoms in the alkyl chain have been synthesized and characterized with respect to self-assembly, supramolecular structure, and phase transitions. The CMCs of AEs bearing 11-18 C atoms were found to range between 0.1 and 10 mM. Differential scanning calorimetric (DSC) studies showed that the transition temperatures (Tt), enthalpies (ΔHt) and entropies (ΔSt) of AEs in the dry state exhibit odd-even alternation, with the odd-chain-length compounds having higher Tt values, but the even-chain-length homologues showing higher values of ΔHt and ΔSt. In DSC measurements on hydrated samples, carried out at pH 5.0 and pH 10.0 (where they exist in cationic and neutral forms, respectively), compounds with 13-18 C atoms in the alkyl chain showed sharp gel-to-liquid crystalline phase transitions, and odd-even alternation was not seen in the thermodynamic parameters. The molecular structure, packing properties, and intermolecular interactions of AEs with 9 and 10 C atoms in the alkyl chain were determined by single crystal X-ray diffraction, which showed that the alkyl chains are packed in a tilted interdigitated bilayer format. d-Spacings obtained from powder X-ray diffraction studies exhibited a linear dependence on the alkyl chain length, suggesting that the other AEs also adopt an interdigitated bilayer structure. Turbidimetric, fluorescence spectroscopic, and isothermal titration calorimetric (ITC) studies established that in aqueous dispersions l-alanine lauryl ester hydrochloride (ALE·HCl) and sodium dodecyl sulfate (SDS) form an equimolar complex. Transmission electron microscopic and DSC studies indicate that the complex exists as unilamellar liposomes, which exhibit a sharp phase transition at ∼39 °C. The aggregates were disrupted at high pH, suggesting that the catanionic complex would be useful to develop a base-labile drug delivery system. ITC studies indicated that ALE·HCl forms

EFFICIENCY OF REAL-TIME PCR FOR 18S rRNA AMPLIFICATION OF SORBUS DOMESTICA, L.

Directory of Open Access Journals (Sweden)

Petronela Poláčeková

2012-10-01

Full Text Available Normal 0 21 false false false SK X-NONE X-NONE Nowadays, the awareness is given more and more to underutilized and  unusual fruits. One of them is Sorbus domestica, L. not only as an endangered species, but as well as a promising and economically usable crop. The work was aimed for finding a total genomic DNA isolating methods from fresh plant material and confirmation of the optimized method by the detection of 18S rRNA gene using real-time PCR. Two commercial isolation kits were tested -  Invisorb® Spin Plant Mini Kit and Wizard ® Genomic DNA. Higher purity and yield of DNA isolation kit showed Invisorb kit. The effective and pure PCR amplification was confirmed for Invisorb, too when 20 ng undiluted DNA at annealing temperature of 64.5 °C.doi:10.5219/203

Reproducibility of O-(2-{sup 18}F-fluoroethyl)-L-tyrosine uptake kinetics in brain tumors and influence of corticoid therapy: an experimental study in rat gliomas

Energy Technology Data Exchange (ETDEWEB)

Stegmayr, Carina; Schoeneck, Michael; Oliveira, Dennis; Willuweit, Antje [Institute of Neuroscience and Medicine, Research Center Juelich, Juelich (Germany); Filss, Christian; Coenen, Heinz H.; Langen, Karl-Josef [Institute of Neuroscience and Medicine, Research Center Juelich, Juelich (Germany); University of Aachen, Department of Nuclear Medicine and Neurology, Aachen (Germany); Galldiks, Norbert [Institute of Neuroscience and Medicine, Research Center Juelich, Juelich (Germany); University of Cologne, Department of Neurology, Cologne (Germany); Shah, N. Jon [Institute of Neuroscience and Medicine, Research Center Juelich, Juelich (Germany); University of Aachen, Department of Nuclear Medicine and Neurology, Aachen (Germany); Juelich-Aachen Research Alliance (JARA) - Section JARA-Brain, Juelich (Germany)

2016-06-15

Positron emission tomography (PET) using O-(2-{sup 18}F-fluoroethyl)-L-tyrosine ({sup 18}F-FET) is a well-established method for the diagnostics of brain tumors. This study investigates reproducibility of {sup 18}F-FET uptake kinetics in rat gliomas and the influence of the frequently used dexamethasone (Dex) therapy. F98 glioma or 9L gliosarcoma cells were implanted into the striatum of 31 Fischer rats. After 10-11 days of tumor growth, the animals underwent dynamic PET after injection of {sup 18}F-FET (baseline). Thereafter, animals were divided into a control group and a group receiving Dex injections, and all animals were reinvestigated 2 days later. Tumor-to-brain ratios (TBR) of {sup 18}F-FET uptake (18-61 min p.i.) and the slope of the time-activity-curves (TAC) (18-61 min p.i.) were evaluated using a Volume-of-Interest (VOI) analysis. Data were analyzed by two-way repeated measures ANOVA and reproducibility by the intraclass correlation coefficient (ICC). The slope of the tumor TACs showed high reproducibility with an ICC of 0.93. A systematic increase of the TBR in the repeated scans was noted (3.7 ± 2.8 %; p < 0.01), and appeared to be related to tumor growth as indicated by a significant correlation of TBR and tumor volume (r = 0.77; p < 0.0001). After correction for tumor growth TBR showed high longitudinal stability with an ICC of 0.84. Dex treatment induced a significant decrease of the TBR (-8.2 ± 6.1 %; p < 0.03), but did not influence the slope of the tumor TAC. TBR of {sup 18}F-FET uptake and tracer kinetics in brain tumors showed high longitudinal stability. Dex therapy may induce a minor decrease of the TBR; this needs further investigation. (orig.)

Generation of L sub-shell photo-ionization cross-sections for elements 18Z92 at energies .320-115.606 keV (A computer program 'LSPICS')

International Nuclear Information System (INIS)

Sharma, Ajay; Mittal, Raj

2005-01-01

L sub-shell photo-ionization cross-sections, σ Li , for elements 18Z92 at energies .320-115.606 keV have been generated from an empirical relation fitted to Scofield's L sub-shell photo-ionization cross-section values. The excitation energy E for an element is constrained by the condition that only L and higher shell vacancies are produced in the elements. The closeness of generated and existing values of Scofield's L sub-shell data recommends the use of generated values in the fields of atomic and molecular physics and for trace elemental analysis. For this purpose computer software 'LSPICS' has been developed. On personal computer LSPICS generates L sub-shell photo-ionization cross-section values in barns just by entering the atomic number of element and excitation photon energy in keV

Comparison of (68)Ga-DOTA-Tyr(3)-octreotide and (18)F-fluoro-L-dihydroxyphenylalanine positron emission tomography in neuroendocrine tumor patients.

Science.gov (United States)

Putzer, D; Gabriel, M; Kendler, D; Henninger, B; Knoflach, M; Kroiss, A; Vonguggenberg, E; Warwitz, B; Virgolini, I J

2010-02-01

(68)Ga-DOTA-Tyr3-octreotide positron emission tomography ((68)Ga-DOTA-TOC PET) and (18)F-fluoro-L-dihydroxyphenylalanine PET ((18)F-DOPA PET) are emerging modalities for imaging of neuroendocrine tumors. This study reports our initial experiences with these two PET modalities on initial diagnosis, staging and restaging in NET patients. Fifteen patients with NET underwent both (68)Ga-DOTA-TOC and (18)F-DOPA PET as well as computed tomography (CT). Image findings were compared on a patient-basis (pathological uptake: yes/no) as well as on a lesion-basis. Contrast-enhanced CT and histological follow-up served as gold standard. Furthermore, imaging results were matched with tumor marker levels and quantitative tracer uptake by the tumor lesions. When comparing (68)Ga-DOTA-TOC and (18)F-DOPA PET, each modality showed a sensitivity of 64% and a specificity of 100% on a patient-based analysis. (68)Ga-DOTA-TOC PET and (18)F-DOPA PET showed equal findings in 7 out of 15 patients and disagreement in 8 patients. (68)Ga-DOTA-TOC revealed more metastases than (18)F-DOPA PET in 6 patients, while (18)F-DOPA PET detected more metastases than (68)Ga-DOTA-TOC in 4 patients. By (68)Ga-DOTA-TOC PET, 208 malignant lesions were detected, while by (18)F-DOPA only 86 lesions were found, and in CT 124, respectively. (68)Ga-DOTA-TOC and (18)F-DOPA PET are useful tools in the detection and staging of NET lesions. Our initial results allow the conclusion that (68)Ga-DOTA-TOC PET may have a stronger clinical impact in NET patients, as it does not only offer diagnostic information, but is decisive for the further treatment management, i. e. PRRT, as well.

Tracking- and Scintillation-Aware Channel Model for GEO Satellite to Land Mobile Terminals at Ku-Band

Directory of Open Access Journals (Sweden)

Ali M. Al-Saegh

2015-01-01

Full Text Available Recent advances in satellite to land mobile terminal services and technologies, which utilize high frequencies with directional antennas, have made the design of an appropriate model for land mobile satellite (LMS channels a necessity. This paper presents LMS channel model at Ku-band with features that enhance accuracy, comprehensiveness, and reliability. The effect of satellite tracking loss at different mobile terminal speeds is considered for directional mobile antenna systems, a reliable tropospheric scintillation model for an LMS scenario at tropical and temperate regions is presented, and finally a new quality indicator module for different modulation and coding schemes is included. The proposed extended LMS channel (ELMSC model is designed based on actual experimental measurements and can be applied to narrow- and wide-band signals at different regions and at different speeds and multichannel states. The proposed model exhibits lower root mean square error (RMSE and significant performance observation compared with the conventional model in terms of the signal fluctuations, fade depth, signal-to-noise ratio (SNR, and quality indicators accompanied for several transmission schemes.

Cave bear (Ursus spelaeus Rosenmüller & Heinroth males' den from Velika Pećina in Duboka Near Kučevo, Eastern Serbia

Directory of Open Access Journals (Sweden)

Dimitrijević Vesna M.

2002-01-01

Full Text Available More a 100 years after the first research in the cave Velika pećina in Duboka near Kučevo cave bear remains were discovered in a small chamber cut off from the passable channels by a 7 m high slope. A whole skull, bones of a forearm in articulation, and other skeleton parts were laying on the cave floor encrusted in travertine cover and in some places overgrown by stalagmites. Bones belonged to adult males, which found there the shelter to hibernate, in a short epizode that ended by closing the channels that once linked this part of the cave to a surface.

Engineering of E. coli for increased production of L- lactic acid

African Journals Online (AJOL)

STORAGESEVER

2009-09-15

Sep 15, 2009 ... Wakamatsu-ku, Kitakyushu-shi, Fukuoka, Japan. Accepted 11 ... was cloned into pBAD vector and transformed into E. coli SZ85 by electroporation. SDS-page and ..... replacement. In the first construct, the internal promoter.

Activation of the 2-5OAS/RNase L pathway in CVB1 or HAV/18f infected FRhK-4 cells does not require induction of OAS1 or OAS2 expression

International Nuclear Information System (INIS)

Kulka, Michael; Calvo, Mona S.; Ngo, Diana T.; Wales, Samantha Q.; Goswami, Biswendu B.

2009-01-01

The latent, constitutively expressed protein RNase L is activated in coxsackievirus and HAV strain 18f infected FRhK-4 cells. Endogenous oligoadenylate synthetase (OAS) from uninfected and virus infected cell extracts synthesizes active forms of the triphosphorylated 2-5A oligomer (the only known activator of RNase L) in vitro and endogenous 2-5A is detected in infected cell extracts. However, only the largest OAS isoform, OAS3, is readily detected throughout the time course of infection. While IFNβ treatment results in an increase in the level of all three OAS isoforms in FRhK-4 cells, IFNβ pretreatment does not affect the temporal onset or enhancement of RNase L activity nor inhibit virus replication. Our results indicate that CVB1 and HAV/18f activate the 2-5OAS/RNase L pathway in FRhK-4 cells during permissive infection through endogenous levels of OAS, but contrary to that reported for some picornaviruses, CVB1 and HAV/18f replication is insensitive to this activated antiviral pathway.

Parametric imaging of {sup 18}F-fluoro-3-deoxy-3-l-fluorothymidine PET data to investigate tumour heterogeneity

Energy Technology Data Exchange (ETDEWEB)

Veronese, M. [University of Padova, Department of Information Engineering (DEI), Padova (Italy); King' s College London, Department of Neuroimaging, Institute of Psychiatry, London (United Kingdom); Rizzo, G.; Bertoldo, A. [University of Padova, Department of Information Engineering (DEI), Padova (Italy); Aboagye, E.O. [Imperial College London, Comprehensive Cancer Imaging Centre, London (United Kingdom)

2014-09-15

[{sup 18}F]Fluoro-3'-deoxy-3'-l-fluorothymidine ([{sup 18}F]FLT) is a tissue proliferation marker which has been widely validated as a tumour-specific imaging tracer for PET. [{sup 18}F]FLT uptake in breast cancer is generally quantified at the region level or through first-order statistical descriptors (mean or maximum value), approaches that ignore the known complexity and heterogeneity of cancer tissues. Our aims were: (1) to validate a robust and reproducible voxel-wise approach to the quantification of [{sup 18}F]FLT PET data in breast cancer patients, and (2) to exploit the entire distribution of the [{sup 18}F]FLT retention estimates and their variability in the tumour region for the prediction of early treatment response. The dataset was derived from 15 patients with stage II-IV breast cancer, scanned twice before chemotherapy and once 1 week after therapy. Using RECIST criteria (after 60 days) nine patients were categorized as responders or nonresponders to treatment. Kinetic modelling (compartmental modelling, Patlak analysis and spectral analysis with iterative filter), tissue-to-plasma ratio and standardized uptake value were applied at the voxel level. Test-retest estimates were used to assess reproducibility and reliability of the [{sup 18}F]FLT uptake values before and after therapy for responder/nonresponder prediction. All the methods provided a measure of [{sup 18}F]FLT uptake that was reliable and reproducible with ICC >0.94. Moreover, a very strong correlation was found among the methods (R {sup 2} > 0.81). All the methods provided a limited number of outliers (<20 % in tumour), with the exception of compartmental modelling (>25 %) which was therefore excluded from the prediction analysis. Differences between before and after therapy in mean voxel-wise uptake in tumour did not allow a complete responder/nonresponder classification. In contrast, considering the full estimate distributions within the tumour (changes in median and mode

Analysis and comparison model for measuring tropospheric scintillation intensity for Ku-band frequency in Malaysia

Directory of Open Access Journals (Sweden)

Mandeep JS

2011-06-01

Full Text Available This study has been based on understanding local propagation signal data distribution characteristics and identifying and predicting the overall impact of significant attenuating factors regarding the propagation path such as impaired propagation for a signal being transmitted. Predicting propagation impairment is important for accurate link budgeting, thereby leading to better communication network system designation. This study has thus used sample data for one year concerning beacon satellite operation in Malaysia from April 2008 to April 2009. Data concerning 12GHz frequency (Ku-band and 40° elevation angle was collected and analysed, obtaining average signal amplitude value, ÷ and also standard deviation ó which is normally measured in dB to obtain long-term scintillation intensity distribution. This analysis showed that scintillation intensity distribution followed Gaussian distribution for long-term data distribution. A prediction model was then selected based on the above; Karasawa,
ITU-R, Van de Kamp and Otung models were compared to obtain the best prediction model performance for selected data regarding specific meteorological conditions. This study showed that the Karasawa model had the best performance for predicting scintillation intensity for the selected da ta.

Y Kuşağının Mobil Öğrenme Uygulama Tercihini Etkileyen Faktörlerin İncelenmesi

OpenAIRE

ALTUNTAŞ, Başar

2017-01-01

Mobilteknolojilerin öğrenme ortamlarına dâhil edilmesiyle birlikte öğrenme faaliyetifiziksel sınırların dışına çıkmış ve farklı bir boyuta evrilmiştir. Tasarlanan öğrenmeuygulamaları kullanıcılarına zamandan ve mekândan bağımsız öğrenme fırsatısunarken, yeni ve farklı deneyimleri de beraberinde getirmiştir. Bu çalışmada,Y kuşağının mobil öğrenme uygulamalarını tercih etmesini ve kullanmasınıetkileyen faktörler incelenmiştir. Teknoloji kabul modeli ile beklenti-kabul modelitemelinde tasarlanan...

Whole-body distribution and dosimetry of O-(2-[18F]fluoroethyl)-L-tyrosine.

Science.gov (United States)

Pauleit, Dirk; Floeth, Frank; Herzog, Hans; Hamacher, Kurt; Tellmann, Lutz; Müller, Hans-W; Coenen, Heinz H; Langen, Karl-J

2003-04-01

The whole-body distribution of O-(2-[(18)F]fluoroethyl)- l-tyrosine (FET) was studied in seven patients with brain tumours by positron emission tomography (PET). Based on the IMEDOSE and MIRDOSE procedures, radiation absorbed doses were estimated from whole-body PET scans acquired approximately 70 and 200 min after i.v. injection of 400 MBq FET. After injection of FET, the peak of radioactivity in the blood was observed after 1.5 min, and a plateau of nearly constant radioactivity was reached at 20 min. The whole-body distribution of FET showed the highest activities in the urinary tract. All other organs exhibited only moderate FET uptake (SUV

Radioimmunoassay of plasma 18-hydroxy-11-deoxycorticosterone and its response to ACTH

International Nuclear Information System (INIS)

May, C.N.; Lewis, P.S.; Horth, C.E.

1979-01-01

A radioimmunoassay for 18-OH-DOC in plasma was developed using an antiserum raised against the γ-lactone derivative. The steroids with the greatest degree of cross reaction were 18-OH-corticosterone-γ-lactone and aldosterone-γ-lactone which showed cross-reactivities of 1.96% and 0.47% respectively. These and other interfering steroids were eliminated by chromatography of the extracts on columns of Sephadex LH-20. The lowest limit of detection of 18-OH-DOC in 1 ml of plasma corresponded to 33 pmol -1 . The intra-assay precision was 9.7, 4.8 and 2.6% at 102.0, 316.1 and 1144.0 pmol l -1 respectively and the interassay precision was 15.3 and 5.4% at 71.3 and 404.7 pmol l -1 respectively. The concentration of 18-OH-DOC in ten normal subjects was 172.1 +- 39.1 pmol l -1 at 09.00 h, 100.9 +- 16.9 pmol l -1 at 12.00 h and 95.8 +-33.3 pmol l -1 at 16.30 h. Plasma 18-OH-DOC and cortisol levels were measured after various intravenous doses of ACTH in three patients with essential hypertension. Lower doses of ACTH caused considerably greater increases in 18-OH-DOC. These results confirm the ACTH dependency of 18-OH-DOC secretion. (author)

The new 1.8 l TFSI engine from Audi. Pt. 1. Base engine and thermomanagement

Energy Technology Data Exchange (ETDEWEB)

Eiser, Alex; Jung, Michael; Adam, Stephan [Audi AG, Ingolstadt (Germany). Engine Development Dept.; Doerr, Joachim [Audi AG, Ingolstadt (Germany). Longitudinally Mounted Engines Dept.

2011-06-15

The launch of the new 1.8 l TFSI engine marks the third generation of the successful four-cylinder gasoline engine family from Audi. It has been completely revised in order to meet ambitious CO{sub 2} targets and ensure compliance with future Euro 6 emissions standards. The new generation features numerous innovative technologies, including an exhaust gas cooling system integrated into the cylinder head, a dual fuel injection system with direct and port-fuel injection as well as the Audi valvelift system with twin camshaft adjustment. A new-style fully electronic coolant control also enables an innovative thermomanagement system to be implemented. This first part of the article details the base engine and the thermomanagement system of the new engine. The second part of the article, which will be published in MTZ 7/8, covers the mixture formation, the combustion method and the turbocharging. (orig.)

Fluorine-18 labelling using [18F]FPyME of a small-glyco drug for potential applications in oncology

International Nuclear Information System (INIS)

Kuhnast, B.; Boisgard, R.; Hinnen, F.; Tavitian, B.; Dolle, F.; El Hadri, A.; Richard, S.; Caravano, A.; Petitou, M.

2011-01-01

Complete text of publication follows: Objectives: Proteoglycans, among which heparan sulfates (HS), are involved in many of the physiopathological steps of tumour development. Through their interaction with target proteins which regulate cell proliferation, migration, adhesion and invasion, HS play a crucial role in tumour angiogenesis and metastasis. Fully synthetic HS-mimetic oligosaccharides, also called small-glyco drugs, can be prepared and their affinity and inhibition profiles can be finely tuned according to the chemical substitutions. Access to these small-glyco drugs labeled with a positron emitter would be highly valuable in PET imaging not only for their pharmacological evaluation in vivo but also for a better understanding of tumour development. Prosthetic labeling is an efficient and reliable methodology that gives access to radiolabeled biological macromolecules. It consists in the preparation of a low molecular weight reagent bearing the radioactive isotope followed by its conjugation with the desired macromolecule. This strategy is particularly convenient when fluorine-18 is considered. Numerous prosthetic reagents have been designed among which [ 18 F]FPyME (a fluoro-pyridine-based maleimide reagent) for a selective conjugation with sulfhydryl functions borne by the macromolecules. In the present contribution, fluorine-18 labeling of the small-glyco drug EP80043 (c-2) via prosthetic labeling with [ 18 F]FPyME of the corresponding sulphated octa-saccharide, functionalized with a sulfhydryl function (2), is reported. Methods: [ 18 F]FPyME was prepared using a three-step radiochemical pathway, HPLC-purified and freed from HPLC solvents as already reported. The target octa-saccharide 2 was first synthesized as its acetylated derivative 1 to avoid intermolecular disulfide bridge formation. Prior to conjugation with [ 18 F]FPyME, 1 mg of 1 dissolved in PBS (0.1 M, pH 7.5, 100 μL) was treated with a 50 mM solution of hydroxylamine in PBS (100 μL) for

In vivo biodistribution and pharmacokinetics of18F-labelled Spiegelmers: a new class of oligonucleotidic radiopharmaceuticals

International Nuclear Information System (INIS)

Boisgard, Raphael; Younes, Cheraz; Tavitian, Bertrand; Kuhnast, Bertrand; Hinnen, Francoise; Dolle, Frederic; Vonhoff, Stefan; Wlotzka, Britta; Klussmann, Sven; Verbavatz, Jean-Marc; Rousseau, Bernard; Fuerste, Jens Peter

2005-01-01

Single-stranded mirror-image oligonucleotides (Spiegelmers) are highly resistant to nuclease degradation and are capable of tightly and specifically binding to protein targets. Here we explored the potential of Spiegelmers as in vivo imaging probes for positron emission tomography (PET). We investigated the biodistribution and pharmacokinetics of [ 18 F]-l-DNA and [ 18 F]-l-RNA Spiegelmers by dynamic quantitative whole-body PET imaging after intravenous administration in non-human primates. Their metabolic profile was explored in primates and rats, and ex vivo autoradiography of [ 125 I]-l-RNA was performed in rat kidneys, the major organ for Spiegelmer uptake. Both [ 18 F]-l-DNA and [ 18 F]-l-RNA Spiegelmers were metabolically stable in plasma during 2 h after injection. No evidence of non-specific binding was found with either type of Spiegelmer in any tissue. The biodistribution and metabolic profiles of [ 18 F]-l-DNA and [ 18 F]-l-RNA Spiegelmers highlight their potential as radiotracers for in vivo imaging applications. (orig.)

6-[F-18]Fluoro-L-Dihydroxyphenylalanine Positron Emission Tomography Is Superior to Conventional Imaging with I-123-Metaiodobenzylguanidine Scintigraphy, Computer Tomography, and Magnetic Resonance Imaging in Localizing Tumors Causing Catecholamine Excess

NARCIS (Netherlands)

Fiebrich, Helle-Brit; Brouwers, Adrienne H.; Kerstens, Michiel N.; Pijl, Milan E. J.; Kema, Ido P.; de Jong, Johan R.; Jager, Pieter L.; Elsinga, Philip H.; Dierckx, Rudi A. J. O.; van der Wal, Jacqueline E.; Sluiter, Wim J.; de Vries, Elisabeth G. E.; Links, Thera P.

2009-01-01

Context: Catecholamine excess is rare, but symptoms may be life threatening. Objective: The objective of the study was to investigate the sensitivity of 6-[F-18]fluoro-L-dihydroxyphenylalanine positron emission tomography (F-18-DOPAPET), compared with I-123-metaiodobenzylguanidine (I-123-MIBG)

From cytokines to pragmatic designs: changing paradigms.

Science.gov (United States)

Heddle, Nancy M

2017-10-01

Emily Cooley was a well-respected medical technologist and morphologist with a remarkable skill set. She was highly regarded both professionally and personally. The "Emily Cooley Lectureship and Award" was established to honor her in particular and medical technologists in general. This article first reviews how a medical laboratory technologist was inspired to become a clinical researcher, then goes on to describe research that led to the discovery of cytokines as the cause of febrile nonhemolytic transfusion and the use of a pragmatic randomized controlled trial design to address evidence of harm when stored red blood cells were transfused. Important lessons for performing quality, meaningful research are highlighted. © 2017 AABB.

Vitamin, Trace Element, and Fatty Acid Levels of Vitex agnus-castus L., Juniperus oxycedrus L., and Papaver somniferum L. Plant Seeds

Directory of Open Access Journals (Sweden)

Ahmet Ozkaya

2013-01-01

Full Text Available The levels of fat-soluble vitamin, trace element and fatty acid of Vitex agnus-castus L., Juniperus oxycedrus L., and Papaver somniferum L. seeds in Turkey were determined by using HPLC, ICP-OES, and GC, respectively. In the Vitex agnus-castus L., Juniperus oxycedrus L., and Papaver somniferum L. seeds, linoleic acid (18 : 2 was determined with the highest level rates (%54.11, %28.03, and %72.14, resp.. In the Vitex agnus-castus L. seeds, R-tocopherol, α-tocopherol, and K1 levels were determined as 9.70 μg/g, 18.20 μg/g, and 24.79 μg/g, respectively; In the Juniperus oxycedrus L. seeds, R-tocopherol, α-tocopherol, and K1 were determined as 18.50 μg/g, 0.84 μg/g, and 5.00 μg/g, respectively, and in the Papaver somniferum L. seeds, R-tocopherol, α-tocopherol, K1, and D2 levels were determined as 43.25 μg/g, 122.05 μg/g, 12.01 μg/g, and 0.62 μg/g, respectively. In the Vitex agnus-castus L., Juniperus oxycedrus L., and Papaver somniferum L. seeds, nickel (Ni, zinc (Zn, and iron (Fe were determined with the trace element level rates (4.42 mg/kg, 10.43 mg/kg, 3.71 mg/kg for Ni, 7.00 mg/kg, 7.70 mg/kg, and 24 mg/kg for Zn and 93.73 mg/kg, 187.95 mg/kg, and 149.64 mg/kg for Fe, resp.. These parameters in seeds are very important for human life.

18F-fluorodeoxyglucose positron emission tomography might be useful for diagnosis of hepatic amyloidosis

Directory of Open Access Journals (Sweden)

Tawada A

2014-06-01

Full Text Available Akinobu Tawada,1 Tatsuo Kanda,1 Takashi Oide,2 Toshio Tsuyuguchi,1 Fumio Imazeki,1,3 Yukio Nakatani,2 Osamu Yokosuka11Department of Gastroenterology, 2Department of Diagnostic Pathology, Chiba University Hospital, Chuo-ku, Chiba, Japan; 3Safety and Health Organization, Chiba University, Inage-ku, Chiba, JapanAbstract: We report on a woman with hepatic involvement of primary systemic (immunoglobulin light chain, AL amyloidosis. Her diagnosis was confirmed by liver biopsy. Clinical symptoms of hepatic amyloidosis are generally mild at its first stage, with most frequent findings being hepatomegaly and alkaline phosphatase elevation. Recent advances in the understanding of the pathophysiology of systemic amyloidosis have made several treatments available. However, its prognosis is occasionally poor. Because liver biopsy is not always safe, other modalities for the diagnosis are needed. Of interest was that fluorodeoxyglucose (FDG uptake into the liver was observed, compared with that into the spleen, in this patient, indicating that FDG positron emission tomography and computed tomography might be useful for the diagnosis of hepatic amyloidosis with mild liver dysfunction.Keywords: amyloidosis, diagnosis, hepatic involvement, FDG PET

The Reactions of Hot Fluorine-18 with Gaseous Carbon Tetrafluoride; Reactions des Atomes {sup 18}F Chauds avec le Tetrafluorure de Carbone en Phase Gazeuse; Reaktsii goryachikh atomov ftora-18 s gazovoj fazoj tetraftormetana; Reacciones de Atomos Calientes de Fluor-18 con Tetrafluoruro de Carbono Gaseoso

Energy Technology Data Exchange (ETDEWEB)

Colebourne, N.; Todd, J. F.J.; Wolfgang, R. [Yale University, New Haven, CT (United States)

1965-04-15

Studies on the reactions of hot Fie atoms with carbon tetrafluoride are reported. Gaseous samples were exposed to the 40-60 MeV (maximum) bremsstrahlung beam of the Yale University Electron Accelerator. The F{sup 19} ({gamma}, n) F{sup 18} process produces F{sup 18} with a kinetic energy of the order of 10{sup 5}-10{sup 6} eV. These species lose energy by collision and are expected to reach the ''chemical'' energy range (< 100 eV) as ground state atoms. Ethylene was found to be a good scavenger for thermal F{sup 18} atoms. Analysis of products was made using standard radio-gas chromatography techniques. The system was found to be quite sensitive to extraneous radiation damage effects and appropriate precautions were taken. Hot displacement reactions, similar to those observed for hot hydrogen, but much less efficient, were found: F{sup 18} + CF{sup 4} --> CF{sub 3}F{sup 18} + F, F{sup 18} +CF{sub 4} --> CF{sub 2}F{sup 18} + (F + F), It was impossible to study the abstraction reaction F{sup 18} + CF{sub 4} --> CF{sub 3} + FF{sup 18} directly. However, indirect evidence suggests that it also has a low efficiency. Detailed studies of the effect of moderator on the F{sup 18} + CF{sub 4} system have been made. The data obtained were analysed by means of the kinetic theory of hot reactions. The system was found to be in accord with this formalism, providing quantitative confirmation of the present interpretation of the results. The carbon tetrafluoride and methane systems provide a basis for some tentative conclusions on the mechanisms of hot fluorine atom reactions. At present it appears that with certain important, but natural, modifications the model first developed for hot hydrogen atoms is applicable [French] Le memoire est consacre a des etudes sur les reactions des atomes {sup 18}F chauds avec le tetrafluorure de carbone. Des echantillons gazeux ont ete exposes a un faisceau de rayonnements de freinage de 40 a 60 MeV (maximum) emis par l'accelerateur d

New Chelators for Low Temperature Al(18)F-Labeling of Biomolecules.

Science.gov (United States)

Cleeren, Frederik; Lecina, Joan; Billaud, Emilie M F; Ahamed, Muneer; Verbruggen, Alfons; Bormans, Guy M

2016-03-16

The Al(18)F labeling method is a relatively new approach that allows radiofluorination of biomolecules such as peptides and proteins in a one-step procedure and in aqueous solution. However, the chelation of the {Al(18)F}(2+) core with the macrocyclic chelators NOTA or NODA requires heating to 100-120 °C. Therefore, we have developed new polydentate ligands for the complexation of {Al(18)F}(2+) with good radiochemical yields at a temperature of 40 °C. The stability of the new Al(18)F-complexes was tested in phosphate buffered saline (PBS) at pH 7.4 and in rat serum. The stability of the Al(18)F-L3 complex was found to be comparable to that of the previously reported Al(18)F-NODA complex up to 60 min in rat serum. Moreover, the biodistribution of Al(18)F-L3 in healthy mice showed the absence of in vivo defluorination since no significant bone uptake was observed, whereas the major fraction of activity at 60 min p.i. was observed in liver and intestines, indicating hepatobiliary clearance of the radiolabeled ligand. The acyclic chelator H3L3 proved to be a good lead candidate for labeling of heat-sensitive biomolecules with fluorine-18. In order to obtain a better understanding of the different factors influencing the formation and stability of the complex, we carried out more in-depth experiments with ligand H3L3. As a proof of concept, we successfully conjugated the new AlF-chelator with the urea-based PSMA inhibitor Glu-NH-CO-NH-Lys to form Glu-NH-CO-NH-Lys(Ahx)L3, and a biodistribution study in healthy mice was performed with the Al(18)F-labeled construct. This new class of AlF-chelators may have a great impact on PET radiochemical space as it will stimulate the rapid development of new fluorine-18 labeled peptides and other heat-sensitive biomolecules.

18{beta}-Glycyrrhetinic acid inhibits adipogenic differentiation and stimulates lipolysis

Energy Technology Data Exchange (ETDEWEB)

Moon, Myung-Hee; Jeong, Jae-Kyo; Lee, You-Jin; Seol, Jae-Won; Ahn, Dong-Choon; Kim, In-Shik [Center for Healthcare Technology Development, Biosafety Research Institute, College of Veterinary Medicine, Chonbuk National University, Jeonju, Jeonbuk 561-756 (Korea, Republic of); Park, Sang-Youel, E-mail: sypark@chonbuk.ac.kr [Center for Healthcare Technology Development, Biosafety Research Institute, College of Veterinary Medicine, Chonbuk National University, Jeonju, Jeonbuk 561-756 (Korea, Republic of)

2012-04-20

Highlights: Black-Right-Pointing-Pointer 18{beta}-GA inhibits adipogenic differentiation in 3T3-L1 preadipocytes and stimulates lipolysis in differentiated adipocytes. Black-Right-Pointing-Pointer Anti-adipogenic effect of 18{beta}-GA is caused by down-regulation of PPAR{gamma} and inactivation of Akt signalling. Black-Right-Pointing-Pointer Lipolytic effect of 18{beta}-GA is mediated by up-regulation of HSL, ATGL and perilipin and activation of HSL. -- Abstract: 18{beta}-Glycyrrhetinic acid (18{beta}-GA) obtained from the herb liquorice has various pharmacological properties including anti-inflammatory and anti-bacterial activities. However, potential biological anti-obesity activities are unclear. In this study, novel biological activities of 18{beta}-GA in the adipogenesis of 3T3-L1 preadipocytes and in lipolysis of differentiated adipocytes were identified. Mouse 3T3-L1 cells were used as an in vitro model of adipogenesis and lipolysis, using a mixture of insulin/dexamethasone/3-isobutyl-1-methylxanthine (IBMX) to induce differentiation. The amount of lipid droplet accumulation was determined by an AdipoRed assay. The expression of several adipogenic transcription factors and enzymes was investigated using real-time reverse transcriptase-polymerase chain reaction (RT-PCR) and Western blotting. 18{beta}-GA dose-dependently (1-40 {mu}M) significantly decreased lipid accumulation in maturing preadipocytes. In 3T3-L1 preadipocytes, 10 {mu}M of 18{beta}-GA down-regulated the transcriptional levels of the peroxisome proliferator-activated receptor {gamma}, CCAAT/enhancer-binding protein {alpha} and adiponectin, which are markers of adipogenic differentiation via Akt phosphorylation. Also, in differentiated adipocytes, 18{beta}-GA increased the level of glycerol release and up-regulated the mRNA of hormone-sensitive lipase, adipose TG lipase and perilipin, as well as the phosphorylation of hormone-sensitive lipase at Serine 563. The results indicate that 18{beta

Vellokõnõ, tillokõnõ : [luuletused] / Hando Runnel

Index Scriptorium Estoniae

Runnel, Hando, 1938-

2002-01-01

Sisu: Vellokõnõ, tillokõnõ ; Maa õnnistamine ; Lats läts nurmõ ; Võibolla ; Sõasalm ; Ku ma Tartost Põlva lätsi ; Ballaad seerest ja pilveveerest ; Imä. Eluloolisi andmeid autori kohta lk. 362-363

ICFTU 18. kongress / Harri Taliga

Index Scriptorium Estoniae

Taliga, Harri, 1957-

2004-01-01

Ilmunud ka: EAKL Teataja : Narodnaja Gazeta, nr. 11, dets. 2004, lk. 1. 5.-10. detsembrini 2004 Jaapanis toimunud Rahvusvahelisest Vabade Ametiühingute Konföderatsiooni (ICFTU) 18. maailmakongressist, mille läbivaks teemaks oli globaalne solidaarsus

Development of Isocratic RP-HPLC Method for Separation and Quantification of L-Citrulline and L-Arginine in Watermelons

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Rasdin Ridwan

2018-01-01

Full Text Available Watermelons (Citrullus lanatus are known to have sufficient amino acid content. In this study, watermelons grown and consumed in Malaysia were investigated for their amino acid content, L-citrulline and L-arginine, by the isocratic RP-HPLC method. Flesh and rind watermelons were juiced, and freeze-dried samples were used for separation and quantification of L-citrulline and L-arginine. Three different mobile phases, 0.7% H3P04, 0.1% H3P04, and 0.7% H3P04 : ACN (90 : 10, were tested on two different columns using Zorbax Eclipse XDB-C18 and Gemini C18 with a flow rate of 0.5 mL/min and a detection wavelength at 195 nm. Efficient separation with reproducible resolution of L-citrulline and L-arginine was achieved using 0.1% H3P04 on the Gemini C18 column. The method was validated and good linearity of L-citrulline and L-arginine was obtained with R2 = 0.9956, y=0.1664x+2.4142 and R2=0.9912, y=0.4100x+3.4850, respectively. L-citrulline content showed the highest concentration in red watermelon of flesh and rind juice extract (43.81 mg/g and 45.02 mg/g, whereas L-arginine concentration was lower than L-citrulline, ranging from 3.39 to 11.14 mg/g. The isocratic RP-HPLC method with 0.1% H3P04 on the Gemini C18 column proved to be efficient for separation and quantification of L-citrulline and L-arginine in watermelons.

[Combined l-thyroxine and l-triiodothyronine replacement therapy in congenital hypothyroidism].

Science.gov (United States)

Péter, Ferenc; Muzsnai, Agota

2013-05-12

L-thyroxine replacement therapy is the treatment of choice for hypothyroidism. Recently, several studies suggested to complete it with l-triiodothyronine in acquired hypothyroidism. To study the role of combined l-thyroxine and l-triiodothyronine therapy in special cases with congenital hypothyroidism. Data of 16 patients (age: 11.9 ± 6.3 years; mean ± SD) are presented who had high serum free thyroxine values or even above the upper limit of reference range (21.16 ± 2.5 pmol/l) together with nonsuppressed TSH levels (15.7 ± 5.7 mIU/l), and therefore received l-triiodothyronine in completion (0.18 ± 0.09 μg/kg) once a day. The combined replacement therapy resulted in a rapid improvement of the hormone parameters (TSH: 4.2 ± 3.15 mIU/l; free thyroxine: 16.55 ± 2.4 and free triiodothyronine: 7.4 ± 1.8 pmol/l). The efficiency of this combined therapy proved to be more evident (TSH: 4.33 ± 3.2 mIU/l; free thyroxine: 16.85 ± 3.1 and free triiodothyronine: 6.4 ± 0.85 pmol/l) in 10 patients treated for a longer period of time (duration of treatment: 2.9 ± 2.0 years). The dose of thyroxine substitution decreased from 2.6 ± 0.9 to 2.18 ± 0.6 μg/kg/day), the ratio of these hormones was between 5:1 and 19:1 and the quotient of free fractions was normalized (3.8 ± 0.4→2.6 ± 0.3) during the replacement therapy. According to the observation of the authors a serious disturbance of feed-back mechanism may develop in some (>5%) children with congenital hypothyroidism (increased TSH release despite elevated free thyroxine level) after normal function of the feed-back system for years. Hormone parameters of these patients improve, then become normal on combined therapy supporting the rationale for this treatment method.

Whole-body distribution and dosimetry of O-(2-[18F]fluoroethyl)-l-tyrosine

International Nuclear Information System (INIS)

Pauleit, Dirk; Floeth, Frank; Herzog, Hans; Tellmann, Lutz; Langen, Karl-J.; Hamacher, Kurt; Coenen, Heinz H.; Mueller, Hans-W.

2003-01-01

The whole-body distribution of O-(2-[ 18 F]fluoroethyl)-l-tyrosine (FET) was studied in seven patients with brain tumours by positron emission tomography (PET). Based on the IMEDOSE and MIRDOSE procedures, radiation absorbed doses were estimated from whole-body PET scans acquired approximately 70 and 200 min after i.v. injection of 400 MBq FET. After injection of FET, the peak of radioactivity in the blood was observed after 1.5 min, and a plateau of nearly constant radioactivity was reached at 20 min. The whole-body distribution of FET showed the highest activities in the urinary tract. All other organs exhibited only moderate FET uptake (SUV ≤1.6) which remained constant between early and late PET scans. No increased uptake was seen in the bone, the biliary tract or the pancreas. Twenty-two percent of the injected activity was excreted 5 h p.i. (approx. 5.3% ID/h). The highest absorbed dose was found for the urinary bladder wall. The effective dose according to ICRP 60 was 16.5 μSv/MBq for adults, which would lead to an effective dose of 6.1 mSv in a PET study using 370 MBq FET. (orig.)

"Küsse lat's ..." : [luuletused] / Kauksi Ülle

Index Scriptorium Estoniae

Kauksi Ülle, pseud., 1962-

2002-01-01

Sisu: "Küsse lat's ..." ; "Vanaimä, ma lupa, ku suurõss kasu ..." ; "Mis-ti küsüt, et ..." ; Ussõ pääl üteld ; "Mis' sõs ku olõ 'pihlõ' ma kesk umma mäke ..." "Kos' sa olt? ..." ; "Maarahva miil ..." ; "Havvakirju ragi yts miis ..." ; Hanõ vai luigõ ; Võlg ; Mu viimäne laul sullõ ; "üts korgõ puu pak mullõ paika ...". Eluloolisi andmeid autori kohta lk. 369

DYEING OF WOOL YARNS WITH LAURUS NOBILIS L. BERRIES

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ERKAN Gökhan

2016-05-01

Full Text Available Nowadays natural dyes have been attracted by many researchers and firms due to demands on sustainable and nontoxic products. In this study the mature berries of bay laurel (Laurus nobilis L. were collected from trees located Kuşadası Turkey. The berries dried at 25oC and % 20-25 relative humidity. Dried berries milled and extracted with ethanol. Extracted dye was used. Three mordanting procedure (pre, meta and post mordanting and two concentrations were applied to wool yarns. Cupric sulfate, ferric sulfate, potassium dichromate and alum was used as mordant Color strength and colorimetric values were measured by Konica-Minolta 3600D spectrophotometer. Fastness to washing, perspiration and light were applied according to ISO 105C06 (A1S, ISO 105E04 and ISO 105B02 (method 2 respectively. The highest color strength (K/S value was 16.6405 and was obtained in the case of premordanting with cupric sulfate at 2 gr/L concentration. If the a* and b* values were examined, the conditions at highest color strength, the yarns had yellow color with a reddish hue. Generally, the fastness properties were moderate and good results were obtained in the case of premordanting procedure. The results show us ethanol extract of bay laurel berries can be used for dyeing of woolen products.

Thalassemia

Science.gov (United States)

Mediterranean anemia; Cooley anemia; Beta thalassemia; Alpha thalassemia ... alpha globin protein are missing or changed (mutated). Beta thalassemia occurs when similar gene defects affect production of ...

Synthesis of n.c.a. {sup 18}F-fluorinated NMDA- and D{sub 4}-receptor ligands via [{sup 18}F]fluorobenzenes; Traegerarme Synthese {sup 18}F-markierter, ausgewaehlter NMDA- und D{sub 4}-Rezeptorliganden durch Einsatz geeigneter [{sup 18}F]Fluorbenzolderivate

Energy Technology Data Exchange (ETDEWEB)

Ludwig, T

2005-11-01

In this thesis new strategies were developed and evaluated for the no-carrier-added (n.c.a.) {sup 18}F-labelling of receptor ligands as radiodiagnostics for characterization of brain receptors using positron-emission-tomography (PET). Special emphasis was placed on the synthesis of n.c.a. ({+-})-3-(4-hydroxy-4-(4-[{sup 18}F]fluorophenyl)-piperidin-l-yl)chroman-4,7-diol, a ligand with high affinity for the NR2B subtype of NMDA receptors and n.c.a. (3-(4-[{sup 18}F]fluorphenoxy)propyl)-(2-(4-tolylphenoxy)ethyl)amine ([{sup 18}F]FPTEA) a dopamine D{sub 4} receptor ligand. In order to synthesize n.c.a. ({+-})-3-(4-hydroxy-4-(4-[{sup 18}F]fluorophenyl)-piperidin-l-yl)chroman-4,7-diol the {sup 18}F-fluoroarylation method via metallorganic intermediates was modified and improved. The suitability of the organometallic {sup 18}F-fluoroarylation agents was proven with several model compounds. High radiochemical yields of 20-30% were obtained also with piperidinone-derivatives. The preparation of a suitable precursor for the synthesis of the NMDA receptor ligand, however, could not be achieved by synthesis of appropriate 1,3-dioxolane protected piperidinone derivatives. Further, the synthesis of n.c.a. ([{sup 18}F]fluoroaryloxy)alkylamines via n.c.a. 4-[{sup 18}F]fluorophenol was developed and evaluated. The synthesis of n.c.a. [{sup 18}F]fluoroarylethers with corresponding model compounds was optimized and led to a radiochemical yield of 25-60%, depending on the alkylhalide used. The preparation of n.c.a. 1-(3-bromopropoxy)-4-[{sup 18}F]fluorobenzene proved advantageous in comparison to direct use of 4-[{sup 18}]fluorophenol for coupling with a corresponding N-protected precursor for the synthesis of n.c.a. [{sup 18}F]FPTEA. With regard to the radiochemical yields and the loss of activity during the synthesis and isolation of n.c.a. 4-[{sup 18}F]fluorophenol and n.c.a. 1-(3-bromopropoxy)-4-[{sup 18}F]fluorobenzene, [{sup 18}F]FPTEA was obtained by reaction with 2-(4-tolyloxy

A Novel Ku-Band/Ka-Band and Ka-Band/E-Band Multimode Waveguide Couplers for Power Measurement of Traveling-Wave Tube Amplifier Harmonic Frequencies

Science.gov (United States)

Wintucky, Edwin G.; Simons, Rainee N.

2015-01-01

This paper presents the design, fabrication and test results for a novel waveguide multimode directional coupler (MDC). The coupler, fabricated from two dissimilar frequency band waveguides, is capable of isolating power at the second harmonic frequency from the fundamental power at the output port of a traveling-wave tube (TWT) amplifier. Test results from proof-of-concept demonstrations are presented for a Ku-band/Ka-band MDC and a Ka-band/E-band MDC. In addition to power measurements at harmonic frequencies, a potential application of the MDC is in the design of a satellite borne beacon source for atmospheric propagation studies at millimeter-wave (mm-wave) frequencies (Ka-band and E-band).

Beretning for undersøgelse af bopladsområde med værkstedsaktivitet fra yngre jernalder/vikingetid, neolitiske anlæg fortrinsvis fra MN A III og en grav fra MN B II. Kalmergården (KU) 2000

DEFF Research Database (Denmark)

Bican, Josefine Franck

2001-01-01

anlæggelse er omtalt nedenfor i en separat beretning ved Lone Gebauer Thomsen (se bilag 2). Yngre jernalder/vikingetid er den periode, der var bedst repræsenteret på pladsen. Her var spor efter en markeds-/produktionsplads, der er registreret vha. 3735 detektorfund, hvor især sølvskatten (KU 2337) skal...

Dzīves stila reklāma žurnālā "Cosmopolitan" (2008. gada janvāris - 2008. gada decembris)

OpenAIRE

Millere, Katrīna

2009-01-01

Bakalaura darbs “Dzīves stila reklāma žurnālā “Cosmopolitan” (2008.gada janvāris – 2008. gada decembris)” pievēršas tādai masu komunikācijas tēmai kā dzīves stila reklāma. Mūsdienu reklāmas pasaule ir tik dažāda un bagātīga ar patērētāju piesaistīšanas paņēmieniem. Tomēr ir reklāmas formāts, kas pārdod nevis preci, bet gan dzīves stilu. Patērētājs, iegādājoties kādu preci iedomājas, ka iegūst sev jaunu statusu. Tomēr vai tas tā ir? Vai arī reklāma meistarīgi spēlē ar cilvēku prātiem? Ba...

Synthesis of n.c.a. 18F-fluorinated NMDA- and D4-receptor ligands via [18F]fluorobenzenes

International Nuclear Information System (INIS)

Ludwig, T.

2005-11-01

In this thesis new strategies were developed and evaluated for the no-carrier-added (n.c.a.) 18 F-labelling of receptor ligands as radiodiagnostics for characterization of brain receptors using positron-emission-tomography (PET). Special emphasis was placed on the synthesis of n.c.a. (±)-3-(4-hydroxy-4-(4-[ 18 F]fluorophenyl)-piperidin-l-yl)chroman-4,7-diol, a ligand with high affinity for the NR2B subtype of NMDA receptors and n.c.a. (3-(4-[ 18 F]fluorphenoxy)propyl)-(2-(4-tolylphenoxy)ethyl)amine ([ 18 F]FPTEA) a dopamine D 4 receptor ligand. In order to synthesize n.c.a. (±)-3-(4-hydroxy-4-(4-[ 18 F]fluorophenyl)-piperidin-l-yl)chroman-4,7-diol the 18 F-fluoroarylation method via metallorganic intermediates was modified and improved. The suitability of the organometallic 18 F-fluoroarylation agents was proven with several model compounds. High radiochemical yields of 20-30% were obtained also with piperidinone-derivatives. The preparation of a suitable precursor for the synthesis of the NMDA receptor ligand, however, could not be achieved by synthesis of appropriate 1,3-dioxolane protected piperidinone derivatives. Further, the synthesis of n.c.a. ([ 18 F]fluoroaryloxy)alkylamines via n.c.a. 4-[ 18 F]fluorophenol was developed and evaluated. The synthesis of n.c.a. [ 18 F]fluoroarylethers with corresponding model compounds was optimized and led to a radiochemical yield of 25-60%, depending on the alkylhalide used. The preparation of n.c.a. 1-(3-bromopropoxy)-4-[ 18 F]fluorobenzene proved advantageous in comparison to direct use of 4-[ 18 ]fluorophenol for coupling with a corresponding N-protected precursor for the synthesis of n.c.a. [ 18 F]FPTEA. With regard to the radiochemical yields and the loss of activity during the synthesis and isolation of n.c.a. 4-[ 18 F]fluorophenol and n.c.a. 1-(3-bromopropoxy)-4-[ 18 F]fluorobenzene, [ 18 F]FPTEA was obtained by reaction with 2-(4-tolyloxy)ethylamine in radiochemical yields of about 25-30% in ethanol or 2-butanone

The use of dynamic O-(2-18F-fluoroethyl)-l-tyrosine PET in the diagnosis of patients with progressive and recurrent glioma.

Science.gov (United States)

Galldiks, Norbert; Stoffels, Gabriele; Filss, Christian; Rapp, Marion; Blau, Tobias; Tscherpel, Caroline; Ceccon, Garry; Dunkl, Veronika; Weinzierl, Martin; Stoffel, Michael; Sabel, Michael; Fink, Gereon R; Shah, Nadim J; Langen, Karl-Josef

2015-09-01

We evaluated the diagnostic value of static and dynamic O-(2-[(18)F]fluoroethyl)-L-tyrosine ((18)F-FET) PET parameters in patients with progressive or recurrent glioma. We retrospectively analyzed 132 dynamic (18)F-FET PET and conventional MRI scans of 124 glioma patients (primary World Health Organization grade II, n = 55; grade III, n = 19; grade IV, n = 50; mean age, 52 ± 14 y). Patients had been referred for PET assessment with clinical signs and/or MRI findings suggestive of tumor progression or recurrence based on Response Assessment in Neuro-Oncology criteria. Maximum and mean tumor/brain ratios of (18)F-FET uptake were determined (20-40 min post-injection) as well as tracer uptake kinetics (ie, time to peak and patterns of the time-activity curves). Diagnoses were confirmed histologically (95%) or by clinical follow-up (5%). Diagnostic accuracies of PET and MR parameters for the detection of tumor progression or recurrence were evaluated by receiver operating characteristic analyses/chi-square test. Tumor progression or recurrence could be diagnosed in 121 of 132 cases (92%). MRI and (18)F-FET PET findings were concordant in 84% and discordant in 16%. Compared with the diagnostic accuracy of conventional MRI to diagnose tumor progression or recurrence (85%), a higher accuracy (93%) was achieved by (18)F-FET PET when a mean tumor/brain ratio ≥2.0 or time to peak dynamic (18)F-FET PET parameters differentiate progressive or recurrent glioma from treatment-related nonneoplastic changes with higher accuracy than conventional MRI. © The Author(s) 2015. Published by Oxford University Press on behalf of the Society for Neuro-Oncology. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Use of combined ion exchangers on the basis of KU-23 and KM-2p cation exchangers for purification of ammonium molybdate and tungstate solutions from phosphate, arsenate, and silicate impurities

International Nuclear Information System (INIS)

Blokhin, A.A.; Majorov, D.Yu.; Kopyrin, A.A.; Taushkanov, V.P.

2002-01-01

Using the Tracer technique ( 32 P) and elementary analysis, potentiality of using combined ionites on the basis of macroporous cation-exchange resins KU-23 or KM-2p and hydrated zirconium oxide for purification of concentrated solutions of ammonium molybdate and tungstate from phosphate-, arsenate-, and silicate-ions impurities was studied. High selectivity of the combined ionites towards impurity ions was ascertained, which permits reducing the content of impurities by a factor of 50-100 compared with the initial one [ru

Korelace mezi sportovní činností a užíváním návykových látek u 14letých žáků a žákyň základních škol ve Slovinsku Correlation between sport activity and drug-taking among 14 year-old primary school male and female pupils in Slovenia

Directory of Open Access Journals (Sweden)

Jože Štihec

2006-02-01

Full Text Available Cílem tohoto průzkumu bylo zjistit, zda u 14letých žáků existuje korelace mezi sportovní aktivitou a užíváním návykových látek. Tento průzkum je založen na dotazníku s 38 proměnnými, přičemž pravděpodobnostní vztahy mezi proměnnými byly testovány pomocí chí-kvadrát testu. Analýza ukázala, že ve svém volném čase se sportu věnuje 80 % chlapců a 85 % dívek. Sportu se věnují většinou dvakrát až třikrát týdně. Většina chlapců se věnuje sportu závodně (39 %, zatímco dívky se věnují především rekreačním pohybovým aktivitám (48 %. Pokud jde o kouření, ke kuřákům patří 4 % procenta chlapců a 12 % dívek. Většina chlapců začala kouřit ve věku 13 let, dívky ve věku 12 let. 90 % chlapců a 94 % dívek již nějaký alkoholický nápoj vyzkoušelo – jde tedy o většinu žáků ve věku od 10 do 13 let. Pokud jde o užívání drog, vyzkoušelo je 18 % chlapců a 26 % dívek. Nejčastějšími typy drog jsou inhalace, pilulky a marihuana. Většina žáků prohlásila, že kouření, pití alkoholu a užívání nelegálních návykových látek vyzkoušela ze zvědavosti. Rodiče většinou podporují děti v provozování sportu. Většina žáků se domnívá, že sport a kouření spolu nejde dohromady. Domnívají se, že sportovní aktivity jsou činnosti, které by od užívání návykových látek mohly odrazovat. Zjistili jsme, že mezi sportovními aktivitami a užíváním legálních i nelegálních návykových látek není statisticky významná korelace. Statisticky významná korelace však byla zjištěna u pití alkoholu v případě chlapců (pivo a víno a inhalace látek v případě dívek. Rozdíly by zřejmě mohly být výraznější v pozdějším věku – při přechodu mezi základní a střední školou. Mladé lidi by bylo možno od užívání legálních i nelegálních návykových látek odradit nabídkou většího množství aktivit, kter

CHARACTERIZATION OF THE PARTIALLY PURIFIED PLANTARCIN SR18 PRODUCED BY LACTOBACILLUS PLANTARUM SR18

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Wagih El-Shouny

2013-04-01

Full Text Available The bacteriocin bound to the cells and that secreted into the culture filtrate of Lactobacillus plantarum SR18 were precipitated by 75% ammomium sulphate, dialysed and further purified by Gel filtration on Sephadex G-100. Bacteriocins were purified from proteins bound to the cell of L. plantarum SR18 (plantarcin SR18 a and culture filtrate proteins (plantarcin SR18 b, respectively. The SDS-PAGE of partially purified Plantarcin SR18a showed a molecular weight of 3.5 KDa. While, plantarcin SR18 b had a molecular weight of 10.3 KDa. The antibacterial activity of the tested plantarcin SR18 preparations suffered no measurable loss after 45 min at 80ºC. Whereas, At 100ºC, significant decrease in the activity of bacteriocin preparations (60- 80 % took place by the end of 45 min. At pH ranged from 5-8, the activity of the plantarcin SR18 preparations suffered no measurable loss. Dissociating agents significantly affected the bacteriocin activity. Thus, tween 80 and mercaptoethanol increased the activity of bacteriocin preparations to 1.2-1.4 fold. Sodium dodecyl sulphate (SDS increased the activity of the tested bacteriocin preparations by about 20%.The lowest residual activity (60% was recorded after treatment with Triton X100 for 45 min. Protease completely inhibited the activities of all forms of plantarcin SR18 after 45 min at 37ºC.

Inhibition of the dapE-Encoded N-Succinyl-L,L-diaminopimelic Acid Desuccinylase from Neisseria meningitidis by L-Captopril

OpenAIRE

Starus, Anna; Nocek, Boguslaw; Bennett, Brian; Larrabee, James A.; Shaw, Daniel L.; Sae-Lee, Wisath; Russo, Marie T.; Gillner, Danuta M.; Makowska-Grzyska, Magdalena; Joachimiak, Andrzej; Holz, Richard C.

2015-01-01

Binding of the competitive inhibitor L-captopril to the dapE-encoded N-succinyl-L,L-diaminopimelic acid desuccinylase from Neisseria meningitidis (NmDapE) was examined by kinetic, spectroscopic, and crystallographic methods. L-Captopril, an angiotensin-converting enzyme (ACE) inhibitor, was previously shown to be a potent inhibitor of the DapE from Haemophilus influenzae (HiDapE) with an IC50 of 3.3 μM and a measured Ki of 1.8 μM and displayed a dose-responsive antibiotic activity toward Esch...

A Chimeric NaV1.8 Channel Expression System Based on HEK293T Cell Line

Directory of Open Access Journals (Sweden)

Xi Zhou

2018-04-01

Full Text Available Among the nine voltage-gated sodium channel (NaV subtypes, NaV1.8 is an attractive therapeutic target for pain. The heterologous expression of recombinant NaV1.8 currents is of particular importance for its electrophysiological and pharmacological studies. However, NaV1.8 expresses no or low-level functional currents when transiently transfected into non-neuronal cell lines. The present study aims to explore the molecular determinants limiting its functional expression and accordingly establish a functional NaV1.8 expression system. We conducted screening analysis of the NaV1.8 intracellular loops by constructing NaV chimeric channels and confirmed that the NaV1.8 C-terminus was the only limiting factor. Replacing this sequence with that of NaV1.4, NaV1.5, or NaV1.7 constructed functional channels (NaV1.8/1.4L5, NaV1.8/1.5L5, and NaV1.8/1.7L5, respectively, which expressed high-level NaV1.8-like currents in HEK293T cells. The chimeric channel NaV1.8/1.7L5 displayed much faster inactivation of its macroscopic currents than NaV1.8/1.4L5 and NaV1.8/1.5L5, and it was the most similar to wild-type NaV1.8 expressed in ND7/23 cells. Its currents were very stable during repetitive depolarizations, while its repriming kinetic was different from wild-type NaV1.8. Most importantly, NaV1.8/1.7L5 pharmacologically resembled wild-type NaV1.8 as revealed by testing their susceptibility to two NaV1.8 selective antagonists, APETx-2 and MrVIB. NaV chimeras study showed that at least the domain 2 and domain 4 of NaV1.8 were involved in binding with APETx-2. Our study provided new insights into the function of NaV1.8 intracellular loops, as well as a reliable and convenient expression system which could be useful in NaV1.8 studies.

Extracted atmospheric impairments on earth-sky signal quality in tropical regions at Ku-band

Science.gov (United States)

Al-Saegh, Ali Mohammed; Sali, Aduwati; Mandeep, J. S.; Ismail, Alyani

2013-11-01

Atmospheric condition variations were shown to have a major effect on the earth sky signal quality at Ku band. Moreover, such variations increased in the tropical regions as compared to temperate areas due to their different weather parameters. With the increase of recent satellite communication technology applications throughout the tropical countries and lack of information regarding the atmospheric impairments analysis, simulation and mitigation techniques, there is an ever increasing need for extracting a unique and accurate performance of the signal quality effects during highly natural tropical weather impairments. This paper presents a new method developed for proper analysis with distinctive and highly realistic performance evaluation for signal quality during the atmospheric conditions variations in 14 tropical areas from the four continents analyzed based on actual measured parameters. The method implementation includes signal attenuation, carrier to noise ratio, symbol energy to noise ratio, and symbol error rate at different areas and different modulation schemes. Furthermore, for improvement in analysis in terms of covering more remarkable regions in tropics, the paper provides new measurements data with analysis for certain region in tropics used as a test bed and to add measurement data of such area to the world's data base for future researchers. The results show a significant investigation and performance observation in terms of weather impairments in tropical regions in general and each region in that area in particular regarding the signal attenuation and error rates accompanied for several transmission schemes.

Direct fluorination of melatonin and 5-hydroxy-L-tryptophan with [18F]F2

International Nuclear Information System (INIS)

Chirakal, R.; Firnau, G.; Garnett, E.S.

1986-01-01

In order that melatonin receptors may be studied in man with positron emission tomography, melatonin labelled with a positron emitting isotope is needed. The preparation of 6-fluoro-melatonin labelled with F-18 is described. Using the same fluorination method, 5-hydroxy-6-(F-18)fluorotryptophan and 4-(F-18)fluoro-5-hydroxy-tryptophan were also prepared. (UK)

3,6-Dithiaoctane-1,8-dicarboxylic acid and its metal complexes

NARCIS (Netherlands)

Bellaart, A.C.; Verbeek, J.L.

1969-01-01

A soln. contg. 1.5 g 3,6-dithiaoctane-1,8-dicarboxylic acid (HL) in 20 ml H2O was treated with 1.8 g Ag2O for 20 min on a boiling water bath to give H[AgL2], m.p. 115-16 Deg (uncor.). A structure is proposed on the basis of ir spectral studies and elec. cond. measurements. H[CuL2] was similarly

Whole-body distribution and dosimetry of O-(2-[{sup 18}F]fluoroethyl)-l-tyrosine

Energy Technology Data Exchange (ETDEWEB)

Pauleit, Dirk [Clinic of Nuclear Medicine, Heinrich-Heine-University Duesseldorf, Duesseldorf (Germany); Clinic of Nuclear Medicine, Research Center Juelich, P.O. Box 1913, 52425, Juelich (Germany); Floeth, Frank [Department of Neurosurgery, Heinrich-Heine-University Duesseldorf, Duesseldorf (Germany); Herzog, Hans; Tellmann, Lutz; Langen, Karl-J. [Institute of Medicine, Research Center Juelich, Juelich (Germany); Hamacher, Kurt; Coenen, Heinz H. [Institute of Nuclear Chemistry, Research Center Juelich, Juelich (Germany); Mueller, Hans-W. [Clinic of Nuclear Medicine, Heinrich-Heine-University Duesseldorf, Duesseldorf (Germany)

2003-04-01

The whole-body distribution of O-(2-[{sup 18}F]fluoroethyl)-l-tyrosine (FET) was studied in seven patients with brain tumours by positron emission tomography (PET). Based on the IMEDOSE and MIRDOSE procedures, radiation absorbed doses were estimated from whole-body PET scans acquired approximately 70 and 200 min after i.v. injection of 400 MBq FET. After injection of FET, the peak of radioactivity in the blood was observed after 1.5 min, and a plateau of nearly constant radioactivity was reached at 20 min. The whole-body distribution of FET showed the highest activities in the urinary tract. All other organs exhibited only moderate FET uptake (SUV {<=}1.6) which remained constant between early and late PET scans. No increased uptake was seen in the bone, the biliary tract or the pancreas. Twenty-two percent of the injected activity was excreted 5 h p.i. (approx. 5.3% ID/h). The highest absorbed dose was found for the urinary bladder wall. The effective dose according to ICRP 60 was 16.5 {mu}Sv/MBq for adults, which would lead to an effective dose of 6.1 mSv in a PET study using 370 MBq FET. (orig.)

Routine production of 18F using 16.5 MeV cyclotron for synthesis of 2-(18F)fluro-2-deoxy-d-glucose (FDG)

International Nuclear Information System (INIS)

Abd Jalil Abd Hamid; Soni, P.S.; Rajan, M.G.R.

2006-01-01

A medium energy cyclotron with maximum of 75 mA beam current is capable of producing most common Positron Emission Tomography (PET) radionuclides in sufficient quantities. The cyclotron has two targets for production of Flourine-18. One is high yield target system (HYT) (1.2 mL) and the other is HYT Generation II (Gen-II) (2.2 mL) and capable of producing 110 and 170 GBq respectively. Enriched 18 O water (>95%) is used for the routine production of Flourine-18 using the 18 O(p,n) 18 F nuclear reaction and irradiated under helium gas pressurized at 59-65 kPa at a beam current of 35 mA - 55 mA for 20-67 minutes. The [ 18 F]fluoride ion produced are used for the synthesis of 2-fluoro-2-deoxy-D-glucose (2-[ 18 F]FDG). Various factors that may effect the production of PET radionuclides and one such factor includes the silver target body often introduce impurity such as silver oxides in form of black particles that can impede the (ID 0.75 mm) delivery line. Such contaminants would reduce the quantity of the available useful radioisotopes, and hinder the subsequent radiopharmaceutical processes. Used of HYT and HYT Gen-II for the routine production of 18 F- in few ten GBq quantities were reported

77 FR 9225 - Allegheny Electric Cooperative, Inc., et al. v. PJM Interconnection, L.L.C.; Organization of PJM...

Science.gov (United States)

2012-02-16

...-58-010] Allegheny Electric Cooperative, Inc., et al. v. PJM Interconnection, L.L.C.; Organization of PJM States, Inc., et al. v. PJM Interconnection, L.L.C.; Notice of Filing Take notice that on February... by section 18.17.4 of the Amended and Restated Operating Agreement of PJM Interconnection, L.L.C. and...

Comparison of stochastic and regression based methods for quantification of predictive uncertainty of model-simulated wellhead protection zones in heterogeneous aquifers

DEFF Research Database (Denmark)

Christensen, Steen; Moore, C.; Doherty, J.

2006-01-01

accurate and required a few hundred model calls to be computed. (b) The linearized regression-based interval (Cooley, 2004) required just over a hundred model calls and also appeared to be nearly correct. (c) The calibration-constrained Monte-Carlo interval (Doherty, 2003) was found to be narrower than......For a synthetic case we computed three types of individual prediction intervals for the location of the aquifer entry point of a particle that moves through a heterogeneous aquifer and ends up in a pumping well. (a) The nonlinear regression-based interval (Cooley, 2004) was found to be nearly...... the regression-based intervals but required about half a million model calls. It is unclear whether or not this type of prediction interval is accurate....

Radiosynthesis of dimethyl-2-[{sup 18}F]-(fluoromethyl)-6-methyl-4-(2-nitrophenyl)-1,4-dihydropyridine-3,5-dicarboxylate for L-type calcium channel imaging

Energy Technology Data Exchange (ETDEWEB)

Sadeghpour, H. [Nuclear Medicine Research Group, Agricultural, Medical and Industrial Research School (AMIRS), Karaj (Iran); Faculty of Pharmacy and Pharmaceutical Sciences Research Center, Tehran Univ. of Medical Sciences, Tehran (Iran); Jalilian, A.R.; Akhlaghi, M.; Mirzaei, M. [Nuclear Medicine Research Group, Agricultural, Medical and Industrial Research School (AMIRS), Karaj (Iran); Shafiee, A. [Faculty of Pharmacy and Pharmaceutical Sciences Research Center, Tehran Univ. of Medical Sciences, Tehran (Iran); Miri, R. [Medicinal and Natural Products Chemistry Research Center, Shiraz Univ. of Medical Sciences, Shiraz (Iran)

2008-07-01

Dimethyl 2-(fluoromethyl)-6-methyl-4-(2-nitrophenyl)-1,4-dihydropyridine-3,5-dicarboxylate 4a, a fluorinated nifedipine analog, has been shown to elicit significant calcium channel blocker activity using a guinea pig ileal longitudinal smooth muscle model. In order to perform biological studies for detection of L-type calcium channel distribution, we decided to prepare the [{sup 18}F]-labeled compound. The latter compound was prepared in no-carrier-added (n.c.a.) form from dimethyl 2-(bromomethyl)-6-methyl-4-(2-nitrophenyl)-1,4-dihydropyridine-3,5-dicarboxylate 2 in one step at 80 C in Kryptofix[222]/K[{sup 18}F]F and acetonitrile as a solvent in 15 min. Column chromatography afforded the radiochemically pure compound in 20 min. Radiochemical purity of the {sup 18}F-nifedipine was determined by RTLC and HPLC (> 98%) and specific activity of 21-48 GBq/{mu}mol (EOB). (orig.)

RESOLUTE PET/MRI Attenuation Correction for O-(2-18F-fluoroethyl-L-tyrosine (FET in Brain Tumor Patients with Metal Implants

Directory of Open Access Journals (Sweden)

Claes N. Ladefoged

2017-08-01

Full Text Available Aim: Positron emission tomography (PET imaging is a useful tool for assisting in correct differentiation of tumor progression from reactive changes, and the radiolabeled amino acid analog tracer O-(2-18F-fluoroethyl-L-tyrosine (FET-PET is amongst the most frequently used. The FET-PET images need to be quantitatively correct in order to be used clinically, which require accurate attenuation correction (AC in PET/MRI. The aim of this study was to evaluate the use of the subject-specific MR-derived AC method RESOLUTE in post-operative brain tumor patients.Methods: We analyzed 51 post-operative brain tumor patients (68 examinations, 200 MBq [18F]-FET investigated in a PET/MRI scanner. MR-AC maps were acquired using: (1 the Dixon water fat separation sequence, (2 the ultra short echo time (UTE sequences, (3 calculated using our new RESOLUTE methodology, and (4 a same day low-dose CT used as reference “gold standard.” For each subject and each AC method the tumor was delineated by isocontouring tracer uptake above a tumor(T-to-brain background (B activity ratio of 1.6. We measured B, tumor mean and maximal activity (TMEAN, TMAX, biological tumor volume (BTV, and calculated the clinical metrics TMEAN/B and TMAX/B.Results: When using RESOLUTE 5/68 studies did not meet our predefined acceptance criteria of TMAX/B difference to CT-AC < ±0.1 or 5%, TMEAN/B < ±0.05 or 5%, and BTV < ±2 mL or 10%. In total, 46/68 studies failed our acceptance criteria using Dixon, and 26/68 using UTE. The 95% limits of agreement for TMAX/B was for RESOLUTE (−3%; 4%, Dixon (−9%; 16%, and UTE (−7%; 10%. The absolute error when measuring BTV was 0.7 ± 1.9 mL (N.S with RESOLUTE, 5.3 ± 10 mL using Dixon, and 1.7 ± 3.7 mL using UTE. RESOLUTE performed best in the identification of the location of peak activity and in brain tumor follow-up monitoring using clinical FET PET metrics.Conclusions: Overall, we found RESOLUTE to be the AC method that most robustly

Inhibition of the dapE-Encoded N-Succinyl-L,L-diaminopimelic Acid Desuccinylase from Neisseria meningitidis by L-Captopril.

Science.gov (United States)

Starus, Anna; Nocek, Boguslaw; Bennett, Brian; Larrabee, James A; Shaw, Daniel L; Sae-Lee, Wisath; Russo, Marie T; Gillner, Danuta M; Makowska-Grzyska, Magdalena; Joachimiak, Andrzej; Holz, Richard C

2015-08-11

Binding of the competitive inhibitor L-captopril to the dapE-encoded N-succinyl-L,L-diaminopimelic acid desuccinylase from Neisseria meningitidis (NmDapE) was examined by kinetic, spectroscopic, and crystallographic methods. L-Captopril, an angiotensin-converting enzyme (ACE) inhibitor, was previously shown to be a potent inhibitor of the DapE from Haemophilus influenzae (HiDapE) with an IC50 of 3.3 μM and a measured Ki of 1.8 μM and displayed a dose-responsive antibiotic activity toward Escherichia coli. L-Captopril is also a competitive inhibitor of NmDapE with a Ki of 2.8 μM. To examine the nature of the interaction of L-captopril with the dinuclear active site of DapE, we have obtained electron paramagnetic resonance (EPR) and magnetic circular dichroism (MCD) data for the enzymatically hyperactive Co(II)-substituted forms of both HiDapE and NmDapE. EPR and MCD data indicate that the two Co(II) ions in DapE are antiferromagnetically coupled, yielding an S = 0 ground state, and suggest a thiolate bridge between the two metal ions. Verification of a thiolate-bridged dinuclear complex was obtained by determining the three-dimensional X-ray crystal structure of NmDapE in complex with L-captopril at 1.8 Å resolution. Combination of these data provides new insights into binding of L-captopril to the active site of DapE enzymes as well as important inhibitor-active site residue interaction's. Such information is critical for the design of new, potent inhibitors of DapE enzymes.

An increased 18F radionuclide production

International Nuclear Information System (INIS)

Panico, M.; Salvadore, M.; Randazzo, G.; Roma, R.; Green, A.; Calicchio, G.F.

1999-01-01

In the 18 F daily preparation a diminished yield of radioisotopic production is often found. This fact, most times, is connected to the altered internal surface of the PEE and teflon lines for the 18 F transferring to the hot cells because of radiations. This anomaly is due to an H 2 18 O insufficient filling into the target. In fact a target foils bombardment causing the release of radioactive Ag+ ions sets in. These ions passing through the transferring line damage it. This problem has been solved by an increased H 2 18 O filling, from 0.7 to 1.3 mL. A further steady increasing in the 18 F production is due to the features of the new target: back plane : integrated in the silver flange; water cooling surface: enlarged with fins; target connections: high pressure fittings. In conclusion a careful filling of the new target has increased the fluorine-18 average daily production from 7.4 GBq to 18.5 GBq, using recovered water (time: thirty minutes; beam: 15 mA) and allows to replace teflon lines every year instead of every three months. (authors)

Análise dos níveis de cinza de 4 resinas compostas micro-híbridas utilizando um sistema de radiografia digital direto =Analisys of the gray scale levels for 4 micro-hibrids composite resins using a radiograph direct digital system

Directory of Open Access Journals (Sweden)

Pereira, Ary Salazar Rubim et al.

2005-01-01

Full Text Available O objetivo deste estudo foi analisar os diferentes níveis de cinza de quatro resinas compostas micro-híbridas, através do sistema de radiografia digital direto Sens-a-Ray. As resinas utilizadas foram: Concept (Vigodent, Herculite (Sybron/Kerr, IntenS (Ivoclar Vivadent e Z 100 (3MESPE, na cor A2. Foram confeccionadas 3 placas de acrílico para cada espessura 2, 3 e 4 mm que possuíam dimensões de um filme periapical. Em todas as placas foram feitos quatro orifícios eqüidistantes com 4 mm de diâmetro onde as resinas compostas foram inseridas, esses orifícios apresentavam 4mm de diâmetro. As amostras foram radiografadas a 30 cm de distância foco-filme do sistema Sens-a-Ray por 0,8 segundo com aparelho de Raios-X (Dabi Atlante de 70 kV e 10 mA. A quantidade dos níveis de cinza, das resinas, foi aferida em pixels pelo sistema Sens-a-Ray. Foram obtidas as seguintes médias: Concept – 2 mm com 79,6; 3 mm com 85,4 e 4 mm com 96,7; Herculite – 2 mm com 65,1; 3 mm com 72,5 e 4 mm com 85,4; IntenS – 2 mm com 138,5; 3 mm com 147,3 e 4 mm com 153,7; Z 100 – 2 mm com 133,5; 3 mm com 143,8 e 4 mm com 150,6. Após os resultados foram submetidos ao teste estatístico ANOVA-Tukey com um nível de significância (p 0,05. A colorimetria foi utilizada para ilustrar a densidade óptica dos compósitos, com cores vermelho, verde e azul, representando, respectivamente do mais radiopaco para o menos radiopaco. Podemos concluir que na medida em que aumentou a espessura das placas os níveis de cinza também aumentaram. A resina Herculite apresentou os menores níveis de cinza, diferindo estatisticamente das demais. As resinas IntenS e Z 100 apresentaram maiores níveis de cinza que as demais. The aim of this study was analysed the different gray scale levels for 4 micro-hybrids composite resins, throught the direct digital radiography device, Sens-a-Ray. The composites used in this study were: Concept (Vigodent, Herculite (Sybron/Kerr, IntenS (Ivoclar

Kinetics of destruction of KU-2 x 8 and AV-17 x 8 ion-exchange resins by the joint action of heating and irradiation

International Nuclear Information System (INIS)

Tulupov, P.E.; Butenko, T.Yu.

1982-01-01

Experimental data indicates a decrease of the exchange capacity of AV-17 x 8 (OH) resin in ion-exchange beds at various temperatures. Losses of exchange of the resin in hydroxyl form after 10,000h of continuous heating at 60, 70, and 80 0 C are 24, 44, and 78% respectively. Partial replacement of the hydroxyl by the salt form is accomplished by appreciable lowering of capacity losses. The trimethlyamine evolved during deamination of AV-17 x 8 anion exchange resin, and only methanol, enters the coolant. Under the influence of ionizing radiation in the active zone the methanol will be converted successively into formaldehyde, formic acid and CO 2 . Thus the maximum temperature of use of the hydroxyl form of te anion-exchange resin AV-17 x 8 (OH) in nuclear power plants can be raised to 70-75 0 C. Brief changes of temperature at 100 0 C do not cause any appreciable losses of exchange capacity either. Physicochemical properties of ion-exchange resins after use in nuclear power plants leads to excessive and unjustified restriction of their service life in the course of a single cycle. Joint action of heating and irradiation on AV-17 anion-exchange resin was studied. It was found that rate constants of the processes of thermal radiation decreases the exchange capacities of the resins in the temperature ranges of interest with relation to nuclear power plants. Calculation of the stability of KU-2 x 8 cation-exchange resin shows that even after a year of use at 100 0 C the loss of its exchange capacity is less than 0.1%. Therefore, under the conditions of use in a nuclear power plant KU-2 x 8 resin can be regarded as absolutely stable. The loss of exchange capacity of AV-17 x 8 resin in C1 form at 100 0 C is of similar magnitude

The synthesis of 18F-labelled amino acid O-(2-[18F]fluoroethyl)-L-tyrosine (FET) in NPI

Czech Academy of Sciences Publication Activity Database

Švecová, Helena; Procházka, Libor; Fedorova, S.; Kropáček, Martin; Melichar, František

2007-01-01

Roč. 2, č. 331 (2007), s. 34-34 ISSN 1619-7070 R&D Projects: GA MPO 2A-1TP1/055 Institutional research plan: CEZ:AV0Z10480505 Keywords : [18F]FET * PET * tumor imaging Subject RIV: FR - Pharmacology ; Medidal Chemistry

Stability and the improved methods of "1"8F-FDG

International Nuclear Information System (INIS)

Zhang Jinming; Li Yungang; Liu Jian; Zhang Xiaojun; Tian Jiahe

2011-01-01

To study the stability of "1"8F-FDG with routinely synthesis at high radio-dose and high radioconcentration, "1"8F-FDG was added 0.1% ethanol or repurification by solid-phase extract ion for radiolytic "1"8F-FDG to improve its radiochemical purity (RCP). The results showed that the RCP declined from 99% to 95% within 4 h at 6 TBq/L for room temperature (RT). The radiolysis could be depressed with 0.1% ethanol, the RCP could be over 95% even if the radioactivity concentration was 7.4 TBq/L at RT for 6 h. The repurification method could improve the RCP of "1"8F-FDG from 80% to 99%. Micro PET/ CT imagings of normal rats showed that the vertebra had high uptake with radiolytic "1"8F-FDG because of impurity. There were no radioactivity uptaking in bone with repuification of "1"8F- FDG. It indicated that 0.1% ethanol could be used as stabilizers for "1"8F-FDG to improve the RCP when "1"8F-FDG had high radio-do se and high radioconcentrtion. The radiolytic 18 F-FDG could be repurified by so lid-phase extraction to remove the radio-impurity. The method of added 0.1% thanot could be combined with repurification method to assure the RCP of "1"8F-FDG for over 95% at any given time andradiodose or contcentrayion. (authors)

Die Aussenhandelstätigkeit der Kaufmannschaft Narvas im 18. Jahrhundert / Viktor Zacharov

Index Scriptorium Estoniae

Zacharov, Viktor, 1951-

2004-01-01

Narva väliskaubanduse õitsengust 17. sajandi lõpus ja 18. sajandi alguses. Muutustest Narva kaubanduses 18. sajandil. Narva kaupmeeskonnast ja selle silmapaistvamatest esindajatest. Narvalaste tegevusest Peterburi kaubanduses

Synthesis, uptake mechanism characterization and biological evaluation of {sup 18}F labeled fluoroalkyl phenylalanine analogs as potential PET imaging agents

Energy Technology Data Exchange (ETDEWEB)

Wang Limin [Department of Chemistry, University of Pennsylvania, Philadelphia, PA 19104 (United States); Qu Wenchao; Lieberman, Brian P.; Ploessl, Karl [Department of Radiology, University of Pennsylvania, Philadelphia, PA 19104 (United States); Kung, Hank F., E-mail: kunghf@gmail.co [Department of Radiology, University of Pennsylvania, Philadelphia, PA 19104 (United States); Department of Pharmacology, University of Pennsylvania, Philadelphia, PA 19104 (United States)

2011-01-15

Introduction: Amino acids based tracers represent a promising class of tumor metabolic imaging agents with successful clinical applications. Two new phenylalanine derivatives, p-(2-[{sup 18}F]fluoroethyl)-L-phenylalanine (FEP, [{sup 18}F]2) and p-(3-[{sup 18}F]fluoropropyl)-L-phenylalanine (FPP, [{sup 18}F]3) were synthesized and evaluated in comparison to clinically utilized O-(2-[{sup 18}F]fluoroethyl)-L-tyrosine (FET, [{sup 18}F]1). Methods: FEP ([{sup 18}F]2) and FPP ([{sup 18}F]3) were successfully synthesized by a rapid and efficient two-step nucleophilic fluorination of tosylate precursors and deprotection reaction. In vitro cell uptake studies were carried out in 9L glioma cells. In vivo studies, 9L tumor xenografts were implanted in Fisher 344 rats. Results: FEP ([{sup 18}F]2) and FPP ([{sup 18}F]3) could be efficiently labeled within 90 min with good enantiomeric purity (>95%), good yield (11-37%) and high specific activity (21-69 GBq/{mu}mol). Cell uptake studies showed FEP had higher uptake than FPP as well as reference ligand FET ([{sup 18}F]1). Uptake mechanism studies suggested that FEP is a selective substrate for system L and prefers its subtype LAT1. In vivo biodistribution studies demonstrated FEP had specific accumulation in tumor cells and tumor to background ratio reached 1.45 at 60 min. Small animal positron emission tomography (PET) imaging studies showed FEP was comparable to FET for imaging rats bearing 9L tumor model. FEP had high uptake in 9L tumor compared to surrounding tissue and was quickly excreted through urinary tract. Conclusion: Biological evaluations indicate that FEP ([{sup 18}F]2) is a potential useful tracer for tumor imaging with PET.

18 autoga jääl & lumes / Tapio Koisaari

Index Scriptorium Estoniae

Koisaari, Tapio

2010-01-01

Suur talveautode võrdlus: Alfa Romeo Mito 1,4 MultiAir; BMW 535i Gran Turismo; Citroën C3 Picasso VTi 120; Dacia Logan MCV 1,6 16V; Ford Ka 1,2 Titanium; Honda Insight 1,3 Elegance; Hyundai i20 1,4 Comfort; Kia Soul 1,6 EX; Mazda3 1,6; Mercedes-Benz E 200 CGI; Opel Astra Sport 1,4 Turbo; Peugeot 3008 Premium 1,6 THP; Seat Exeo 2,0 TSI Style; Škoda Yeti 1,2 TSI Experience; Subaru Legacy 2,0 R; Suzuki Alto 1,0 GL; Toyota Prius 1,8 HSD Premium; Volkswagen Polo 1,2 TSI

Either non-homologous ends joining or homologous recombination is required to repair double-strand breaks in the genome of macrophage-internalized Mycobacterium tuberculosis.

Science.gov (United States)

Brzostek, Anna; Szulc, Izabela; Klink, Magdalena; Brzezinska, Marta; Sulowska, Zofia; Dziadek, Jaroslaw

2014-01-01

The intracellular pathogen Mycobacterium tuberculosis (Mtb) is constantly exposed to a multitude of hostile conditions and is confronted by a variety of potentially DNA-damaging assaults in vivo, primarily from host-generated antimicrobial toxic radicals. Exposure to reactive nitrogen species and/or reactive oxygen species causes different types of DNA damage, including oxidation, depurination, methylation and deamination, that can result in single- or double-strand breaks (DSBs). These breaks affect the integrity of the whole genome and, when left unrepaired, can lead to cell death. Here, we investigated the role of the DSB repair pathways, homologous recombination (HR) and non-homologous ends joining (NHEJ), in the survival of Mtb inside macrophages. To this end, we constructed Mtb strains defective for HR (ΔrecA), NHEJ [Δ(ku,ligD)], or both DSB repair systems [Δ(ku,ligD,recA)]. Experiments using these strains revealed that either HR or NHEJ is sufficient for the survival and propagation of tubercle bacilli inside macrophages. Inhibition of nitric oxide or superoxide anion production with L-NIL or apocynin, respectively, enabled the Δ(ku,ligD,recA) mutant strain lacking both systems to survive intracellularly. Complementation of the Δ(ku,ligD,recA) mutant with an intact recA or ku-ligD rescued the ability of Mtb to propagate inside macrophages.

Either non-homologous ends joining or homologous recombination is required to repair double-strand breaks in the genome of macrophage-internalized Mycobacterium tuberculosis.

Directory of Open Access Journals (Sweden)

Anna Brzostek

Full Text Available The intracellular pathogen Mycobacterium tuberculosis (Mtb is constantly exposed to a multitude of hostile conditions and is confronted by a variety of potentially DNA-damaging assaults in vivo, primarily from host-generated antimicrobial toxic radicals. Exposure to reactive nitrogen species and/or reactive oxygen species causes different types of DNA damage, including oxidation, depurination, methylation and deamination, that can result in single- or double-strand breaks (DSBs. These breaks affect the integrity of the whole genome and, when left unrepaired, can lead to cell death. Here, we investigated the role of the DSB repair pathways, homologous recombination (HR and non-homologous ends joining (NHEJ, in the survival of Mtb inside macrophages. To this end, we constructed Mtb strains defective for HR (ΔrecA, NHEJ [Δ(ku,ligD], or both DSB repair systems [Δ(ku,ligD,recA]. Experiments using these strains revealed that either HR or NHEJ is sufficient for the survival and propagation of tubercle bacilli inside macrophages. Inhibition of nitric oxide or superoxide anion production with L-NIL or apocynin, respectively, enabled the Δ(ku,ligD,recA mutant strain lacking both systems to survive intracellularly. Complementation of the Δ(ku,ligD,recA mutant with an intact recA or ku-ligD rescued the ability of Mtb to propagate inside macrophages.

A comparison of EF-18 agar and modified brilliant green agar with lutensit for isolation of Salmonella from poultry samples

DEFF Research Database (Denmark)

Petersen, Line Hedegård

1997-01-01

-Vassiliadis broth, and 3) Plating onto EF-18 agar and BGA/L simultaneously. From a total of 1101 samples, Salmonella was isolated from 158, 157 of which were faecal samples. Thirtyone of these isolates were recovered on one medium only, 18 could not be found on BGA/L and 13 could not be found on EF-18 agar....... The relative specificity and sensitivity of each plating agar was determined by enumeration of false-positive and false-negative reactions. EF-18 agar compared favourably with BGA/L, displaying a sensitivity of 0.92 as opposed to 0.89 for BGA/L, calculated for the ''fecal samples'' group only. The calculated...... specificities for each group of samples were likewise considerably higher for EF-18 agar (0.75-0.91) than for BGA/L (0.35-0.55). Though EF-18 agar is slightly more expensive than BGA/L, the routine use of the former may result in a considerable reduction in overall laboratory costs due to its superior...

Enhancing freezing tolerance of Brassica napus L. by overexpression of a stearoyl-acyl carrier protein desaturase gene (SAD) from Sapium sebiferum (L.) Roxb.

Science.gov (United States)

Peng, Dan; Zhou, Bo; Jiang, Yueqiao; Tan, XiaoFeng; Yuan, DeYi; Zhang, Lin

2018-07-01

Sapium sebiferum (L.) Roxb. is an important woody oil tree and traditional herbal medicine in China. Stearoyl-acyl carrier protein desaturase (SAD) is a dehydrogenase enzyme that plays a key role in the transformation of saturated fatty acids into unsaturated fatty acids in oil; these fatty acids greatly influence the freezing tolerance of plants. However, it remains unclear whether freezing tolerance can be regulated by the expression level of SsSAD in S. sebiferum L. Our research indicated that SsSAD expression in S. sebiferum L. increased under freezing stress. To further confirm this result, we constructed a pEGAD-SsSAD vector and transformed it into B. napus L. W10 by Agrobacterium tumefaciens-mediated transformation. Transgenic plants that overexpressed the SsSAD gene exhibited significantly higher linoleic (18:2) and linolenic acid (18:3) content and advanced freezing tolerance. These results suggest that SsSAD overexpression in B. napus L. can increase the content of polyunsaturated fatty acids (PUFAs) such as linoleic (18:2) and linolenic acid (18:3), which are likely pivotal in improving freezing tolerance in B. napus L. plants. Thus, SsSAD overexpression could be useful in the production of freeze-tolerant varieties of B. napus L. Copyright © 2018 Elsevier B.V. All rights reserved.