1
|
Aprile E, Aalbers J, Agostini F, Alfonsi M, Amaro FD, Anthony M, Arneodo F, Barrow P, Baudis L, Bauermeister B, Benabderrahmane ML, Berger T, Breur PA, Brown A, Brown A, Brown E, Bruenner S, Bruno G, Budnik R, Bütikofer L, Calvén J, Cardoso JMR, Cervantes M, Cichon D, Coderre D, Colijn AP, Conrad J, Cussonneau JP, Decowski MP, de Perio P, Di Gangi P, Di Giovanni A, Diglio S, Eurin G, Fei J, Ferella AD, Fieguth A, Fulgione W, Gallo Rosso A, Galloway M, Gao F, Garbini M, Gardner R, Geis C, Goetzke LW, Grandi L, Greene Z, Grignon C, Hasterok C, Hogenbirk E, Howlett J, Itay R, Kaminsky B, Kazama S, Kessler G, Kish A, Landsman H, Lang RF, Lellouch D, Levinson L, Lin Q, Lindemann S, Lindner M, Lombardi F, Lopes JAM, Manfredini A, Mariş I, Marrodán Undagoitia T, Masbou J, Massoli FV, Masson D, Mayani D, Messina M, Micheneau K, Molinario A, Morå K, Murra M, Naganoma J, Ni K, Oberlack U, Pakarha P, Pelssers B, Persiani R, Piastra F, Pienaar J, Pizzella V, Piro MC, Plante G, Priel N, Rauch L, Reichard S, Reuter C, Riedel B, Rizzo A, Rosendahl S, Rupp N, Saldanha R, Dos Santos JMF, Sartorelli G, Scheibelhut M, Schindler S, Schreiner J, Schumann M, Scotto Lavina L, Selvi M, Shagin P, Shockley E, Silva M, Simgen H, Sivers MV, Stein A, Thapa S, Thers D, Tiseni A, Trinchero G, Tunnell C, Vargas M, Upole N, Wang H, Wang Z, Wei Y, Weinheimer C, Wulf J, Ye J, Zhang Y, Zhu T. First Dark Matter Search Results from the XENON1T Experiment. PHYSICAL REVIEW LETTERS 2017; 119:181301. [PMID: 29219593 DOI: 10.1103/physrevlett.119.181301] [Citation(s) in RCA: 67] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/25/2017] [Indexed: 06/07/2023]
Abstract
We report the first dark matter search results from XENON1T, a ∼2000-kg-target-mass dual-phase (liquid-gas) xenon time projection chamber in operation at the Laboratori Nazionali del Gran Sasso in Italy and the first ton-scale detector of this kind. The blinded search used 34.2 live days of data acquired between November 2016 and January 2017. Inside the (1042±12)-kg fiducial mass and in the [5,40] keV_{nr} energy range of interest for weakly interacting massive particle (WIMP) dark matter searches, the electronic recoil background was (1.93±0.25)×10^{-4} events/(kg×day×keV_{ee}), the lowest ever achieved in such a dark matter detector. A profile likelihood analysis shows that the data are consistent with the background-only hypothesis. We derive the most stringent exclusion limits on the spin-independent WIMP-nucleon interaction cross section for WIMP masses above 10 GeV/c^{2}, with a minimum of 7.7×10^{-47} cm^{2} for 35-GeV/c^{2} WIMPs at 90% C.L.
Collapse
|
2
|
Hovland J, Kessler G. Elementary Teachers’ Technology Integration Self-Efficacy for Teaching Nutrition. J Acad Nutr Diet 2017. [DOI: 10.1016/j.jand.2017.06.163] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
|
3
|
|
4
|
Kessler G. Corrigendum. NUCL SCI ENG 2017. [DOI: 10.13182/nse159-228] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
|
5
|
Broeders CHM, Kessler G. Fuel Cycle Options for the Production and Utilization of Denatured Plutonium. NUCL SCI ENG 2017. [DOI: 10.13182/nse07-a2681] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
|
6
|
Kessler G. Proliferation Resistance of Americium Originating from Spent Irradiated Reactor Fuel of Pressurized Water Reactors, Fast Reactors, and Accelerator-Driven Systems with Different Fuel Cycle Options. NUCL SCI ENG 2017. [DOI: 10.13182/nse159-56] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
|
7
|
Aprile E, Aalbers J, Agostini F, Alfonsi M, Amaro FD, Anthony M, Arneodo F, Barrow P, Baudis L, Bauermeister B, Benabderrahmane ML, Berger T, Breur PA, Brown A, Brown E, Bruenner S, Bruno G, Budnik R, Bütikofer L, Calvén J, Cardoso JMR, Cervantes M, Cichon D, Coderre D, Colijn AP, Conrad J, Cussonneau JP, Decowski MP, de Perio P, Di Gangi P, Di Giovanni A, Diglio S, Eurin G, Fei J, Ferella AD, Fieguth A, Franco D, Fulgione W, Gallo Rosso A, Galloway M, Gao F, Garbini M, Geis C, Goetzke LW, Greene Z, Grignon C, Hasterok C, Hogenbirk E, Itay R, Kaminsky B, Kessler G, Kish A, Landsman H, Lang RF, Lellouch D, Levinson L, Lin Q, Lindemann S, Lindner M, Lopes JAM, Manfredini A, Maris I, Marrodán Undagoitia T, Masbou J, Massoli FV, Masson D, Mayani D, Messina M, Micheneau K, Miguez B, Molinario A, Murra M, Naganoma J, Ni K, Oberlack U, Pakarha P, Pelssers B, Persiani R, Piastra F, Pienaar J, Pizzella V, Piro MC, Plante G, Priel N, Rauch L, Reichard S, Reuter C, Rizzo A, Rosendahl S, Rupp N, Dos Santos JMF, Sartorelli G, Scheibelhut M, Schindler S, Schreiner J, Schumann M, Scotto Lavina L, Selvi M, Shagin P, Silva M, Simgen H, Sivers MV, Stein A, Thers D, Tiseni A, Trinchero G, Tunnell C, Wang H, Wei Y, Weinheimer C, Wulf J, Ye J, Zhang Y. Search for Electronic Recoil Event Rate Modulation with 4 Years of XENON100 Data. PHYSICAL REVIEW LETTERS 2017; 118:101101. [PMID: 28339273 DOI: 10.1103/physrevlett.118.101101] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/03/2017] [Indexed: 06/06/2023]
Abstract
We report on a search for electronic recoil event rate modulation signatures in the XENON100 data accumulated over a period of 4 yr, from January 2010 to January 2014. A profile likelihood method, which incorporates the stability of the XENON100 detector and the known electronic recoil background model, is used to quantify the significance of periodicity in the time distribution of events. There is a weak modulation signature at a period of 431_{-14}^{+16} day in the low energy region of (2.0-5.8) keV in the single scatter event sample, with a global significance of 1.9σ; however, no other more significant modulation is observed. The significance of an annual modulation signature drops from 2.8σ, from a previous analysis of a subset of this data, to 1.8σ with all data combined. Single scatter events in the low energy region are thus used to exclude the DAMA/LIBRA annual modulation as being due to dark matter electron interactions via axial vector coupling at 5.7σ.
Collapse
|
8
|
Aprile E, Aalbers J, Agostini F, Alfonsi M, Anthony M, Arazi L, Arisaka K, Arneodo F, Balan C, Barrow P, Baudis L, Bauermeister B, Breur PA, Brown A, Brown E, Bruenner S, Bruno G, Budnik R, Bütikofer L, Cardoso JMR, Cervantes M, Coderre D, Colijn AP, Contreras H, Cussonneau JP, Decowski MP, de Perio P, Di Giovanni A, Duchovni E, Fattori S, Ferella AD, Fieguth A, Fulgione W, Gao F, Garbini M, Geis C, Goetzke LW, Grignon C, Gross E, Hampel W, Hasterok C, Itay R, Kaether F, Kaminsky B, Kessler G, Kish A, Landsman H, Lang RF, Le Calloch M, Lellouch D, Levinson L, Levy C, Lindemann S, Lindner M, Lopes JAM, Lyashenko A, Macmullin S, Marrodán Undagoitia T, Masbou J, Massoli FV, Mayani D, Melgarejo Fernandez AJ, Meng Y, Messina M, Micheneau K, Miguez B, Molinario A, Murra M, Naganoma J, Ni K, Oberlack U, Orrigo SEA, Pakarha P, Persiani R, Piastra F, Pienaar J, Plante G, Priel N, Rauch L, Reichard S, Reuter C, Rizzo A, Rosendahl S, Dos Santos JMF, Sartorelli G, Schindler S, Schreiner J, Schumann M, Scotto Lavina L, Selvi M, Shagin P, Simgen H, Teymourian A, Thers D, Tiseni A, Trinchero G, Tunnell C, Wall R, Wang H, Weber M, Weinheimer C, Zhang Y. Search for Event Rate Modulation in XENON100 Electronic Recoil Data. PHYSICAL REVIEW LETTERS 2015; 115:091302. [PMID: 26371638 DOI: 10.1103/physrevlett.115.091302] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/17/2015] [Indexed: 06/05/2023]
Abstract
We have searched for periodic variations of the electronic recoil event rate in the (2-6) keV energy range recorded between February 2011 and March 2012 with the XENON100 detector, adding up to 224.6 live days in total. Following a detailed study to establish the stability of the detector and its background contributions during this run, we performed an unbinned profile likelihood analysis to identify any periodicity up to 500 days. We find a global significance of less than 1σ for all periods, suggesting no statistically significant modulation in the data. While the local significance for an annual modulation is 2.8σ, the analysis of a multiple-scatter control sample and the phase of the modulation disfavor a dark matter interpretation. The DAMA/LIBRA annual modulation interpreted as a dark matter signature with axial-vector coupling of weakly interacting massive particles to electrons is excluded at 4.8σ.
Collapse
|
9
|
Wirbel R, Kessler G, Lommel D. [Multicentric osseous giant cell tumor]. ROFO-FORTSCHR RONTG 2014; 186:508-10. [PMID: 24407710 DOI: 10.1055/s-0033-1356036] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
|
10
|
Rineiski A, Kessler G. Proliferation-resistant fuel options for thermal and fast reactors avoiding neptunium production. NUCLEAR ENGINEERING AND DESIGN 2010. [DOI: 10.1016/j.nucengdes.2009.11.003] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
|
11
|
Kessler G. Steady state and transient temperature profiles in a multishell spherical system heated internally by reactor-grade plutonium. NUCLEAR ENGINEERING AND DESIGN 2009. [DOI: 10.1016/j.nucengdes.2009.07.018] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
|
12
|
Sieder R, Kraft D, Schilling B, Kessler G, Grünes G, Kurz R. Rechnergestützte Blutdruckregelung nach Herzoperationen. BIOMED ENG-BIOMED TE 2009. [DOI: 10.1515/bmte.1988.33.s2.73] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
|
13
|
Kessler G, Schöntag G, Eisenhart-Rothe B. Aminosäurespiegel-Untersuchungen an Blutkonserven. Transfus Med Hemother 2009. [DOI: 10.1159/000221209] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
|
14
|
Kessler G, Höbel W, Goel B, Seifritz W. Potential nuclear explosive yield of reactor-grade plutonium using the disassembly theory of early reactor safety analysis. NUCLEAR ENGINEERING AND DESIGN 2008. [DOI: 10.1016/j.nucengdes.2008.08.014] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
|
15
|
Kessler G. Requirements for nuclear energy in the 21st century nuclear energy as a sustainable energy source. PROGRESS IN NUCLEAR ENERGY 2002. [DOI: 10.1016/s0149-1970(02)00024-0] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
|
16
|
Giulivi A, Slinger R, Tepper M, Sher G, Scalia V, Kessler G, Gill P. Prevalence of GBV-C/hepatitis G virus viremia and anti-E2 in Canadian blood donors. Vox Sang 2001; 79:201-5. [PMID: 11155070 DOI: 10.1159/000056731] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
BACKGROUND AND OBJECTIVES GB virus C (GBV-C)/hepatitis G virus (HGV) is a recently recognized parenterally and sexually transmitted agent. The prevalence of GBV-C/HGV markers in Canadian blood donors has not been previously studied and was therefore determined. MATERIALS AND METHODS Blood donors [identity unlinked (IU), short-term temporarily deferred (STTD) and autologous groups] and donor samples with antibodies to hepatitis C (anti-HCV) or hepatitis B core were tested for GBV-C/HGV RNA and for antibodies to E2 antigen (anti-E2). RESULTS GBV-C/HGV RNA was found in 1.1% and anti-E2 in 7.3% of the combined IU/STTD donor group. Viremia was much more common in anti-HCV-positive samples (12.5%); anti-E2 was present in >50% of this group. In the STTD group, female gender was significantly associated with viremia. CONCLUSION GBV-C/HGV infection is relatively common in Canadian donors, and a small proportion are viremic. The association of female gender and viremia was unexpected. Further study is needed to clarify the epidemiology and natural history of GBV-C/HGV infection.
Collapse
|
17
|
Giulivi A, Slinger R, Tepper M, Sher G, Scalia V, Kessler G, Gill P. Prevalence of GBV-C/hepatitis G virus viremia and anti-E2 in Canadian blood donors. Vox Sang 2001. [PMID: 11155070 DOI: 10.1046/j.1423-0410.2000.7940201.x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
BACKGROUND AND OBJECTIVES GB virus C (GBV-C)/hepatitis G virus (HGV) is a recently recognized parenterally and sexually transmitted agent. The prevalence of GBV-C/HGV markers in Canadian blood donors has not been previously studied and was therefore determined. MATERIALS AND METHODS Blood donors [identity unlinked (IU), short-term temporarily deferred (STTD) and autologous groups] and donor samples with antibodies to hepatitis C (anti-HCV) or hepatitis B core were tested for GBV-C/HGV RNA and for antibodies to E2 antigen (anti-E2). RESULTS GBV-C/HGV RNA was found in 1.1% and anti-E2 in 7.3% of the combined IU/STTD donor group. Viremia was much more common in anti-HCV-positive samples (12.5%); anti-E2 was present in >50% of this group. In the STTD group, female gender was significantly associated with viremia. CONCLUSION GBV-C/HGV infection is relatively common in Canadian donors, and a small proportion are viremic. The association of female gender and viremia was unexpected. Further study is needed to clarify the epidemiology and natural history of GBV-C/HGV infection.
Collapse
|
18
|
Akçetin Z, Pregla R, Busch A, Kessler G, Heynemann H, Holtz J, Brömme H. Lipid peroxidation and the expressional regulation of the heat-shock response during ischemia-reperfusion of rat kidney. Urol Int 2001; 65:32-9. [PMID: 10965299 DOI: 10.1159/000064831] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Because of the continuing shortage of donor organs, 'marginal kidneys' are increasingly being used. The purpose of our experiments was to characterize the extent of lipid peroxidation after ischemia-reperfusion (IR) injury in rat kidney, to analyze the expressional regulation of the heat-shock response and now to discuss the clinical application of these results. After ischemia, xanthine oxidase (XO) is thought to be the main oxygen radical-generating system and malondialdehyde (MDA) is considered to be a marker of LPO. In young rats (10 weeks) a unilateral warm ischemia of 40 and 60 min duration with subsequent reperfusion up to 1 h was conducted. Beside the 'footprints' of oxidative stress, the cytosolic antioxidative capacity, expressed as superoxide anion (SOA) scavenging capacity, was investigated. There was only a moderate and transient increase of renal MDA 5 and 10 min after the onset of reoxygenation (133.57/70.67 and 97.84/91.57 vs. 49.47 nmol/g wet weight (ww) in preischemic controls). ATP breakdown (to 83/65 from 2,947 nmol/g ww) with consecutive accumulation of hypoxanthine (up to 1,105 nmol/g ww) at the end of the ischemic period and the subsequent rapid decline of hypoxanthine by XO during reperfusion were used for an assessment of the SOA-generating capacity of these kidneys. Only 1/25-1/50 of the kidney cytosol was able to scavenge the whole amount of SOA generated by the total XO activity of rat kidney. Thus, it could be analytically and stoichiometrically shown that after IR there is only a moderate oxidative stress in kidneys of young rats; this is due to their high SOA-scavenging capacity compared to their SOA-generating ability. We investigated the time course of HSP70-1 and -2 mRNA expression and its relation to cellular ATP levels in renal cortex after different periods of unilateral warm renal ischemia (10-60 min) and reperfusion (up to 60 min) in 10-week-old male Wistar rats, since IR is known to cause induction of both genes. Immediately after ischemia there was a significant induction of both HSP70i genes. While HSP70-1 expression constantly increased (up to 4-fold) during reperfusion, even to a higher extent with prolongation of ischemia, HSP70-2 mRNA - generally being expressed on a far lower level than HSP70-1 mRNA - was strongly induced (3-fold) during reperfusion only after brief periods (10 min) of ischemia. Cellular ATP levels rapidly dropped down to 5% with ischemia and the pattern of recovery during reperfusion significantly depended on the duration of the ischemic period thus showing a good relation to the heat-shock (protein) gene expression. We conclude that the HSP70-2 is the more sensitive gene with a lower threshold activation by mild injury, while the HSP70-1 gene mediates the big response of HSP induction after severe injury. Thus, the measurement of the cytosolic antioxidative capacity and the differential expression of HSP70-1 and -2 mRNA could be promising clinical tools to assess the donor viability.
Collapse
|
19
|
Kessler G. The passport system and state control over population flows in the Soviet Union, 1932-1940. CAHIERS DU MONDE RUSSE 2001; 42:477-503. [PMID: 20020566 DOI: 10.4000/monderusse.98] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
|
20
|
Kessler G. The 1932-1933 crisis and its aftermath beyond the epicenters of famine: the Urals region. HARVARD UKRAINIAN STUDIES 2001; 25:253-265. [PMID: 20034144] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
|
21
|
Wang CK, Zino JF, Kessler G. Enhancement of a 252Cf-based neutron beam via subcritical multiplication for neutron capture therapy. Appl Radiat Isot 2000; 53:811-4. [PMID: 11003524 DOI: 10.1016/s0969-8043(00)00237-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Previous studies indicated that an epithermal-neutron beam based on bare 252Cf is not feasible for neutron capture therapy (NCT). It was reported that a clinically useful epithermal-neutron beam requires a minimum of 1.0 g of 252Cf, which is more than twice the US current annual supply. However, it was reasoned that the required quantity of 252Cf could be dramatically reduced when used with a subcritical multiplying assembly (SMA). This reasoning is based on the assumption that the epithermal-neutron beam intensity for NCT is directly proportional to the fission neutron population, and that the neutron multiplying factor of the SMA can be estimated by 1/(1 - k(eff)). We have performed detailed Monte Carlo calculations to investigate the validity of the above reasoning. Our results show that 1/(1 - k(eff)) grossly overestimates the beam enhancement factor for NCT. For example, Monte Carlo calculations predict a beam enhancement factor of 6.0 for an optimized SMA geometry with k(eff) = 0.968. This factor is much less than 31 predicted by 1/(1 - k(eff)). The overestimation is due to the fact that most of the neutrons produced in the SMA are self-shielded, whereas self-shielding is negligible in a bare 252Cf source. Since the beam intensity of a 0.1 g 252Cf with the optimized SMA enhancement is still more than an order of magnitude too low compared to the existing reactor beams, we conclude that the enhancement via an SMA for a 252Cf-based epithermal-neutron beam is inadequate for NCT.
Collapse
|
22
|
Hu YW, Balaskas E, Furione M, Yen PH, Kessler G, Scalia V, Chui L, Sher G. Comparison and application of a novel genotyping method, semiautomated primer-specific and mispair extension analysis, and four other genotyping assays for detection of hepatitis C virus mixed-genotype infections. J Clin Microbiol 2000; 38:2807-13. [PMID: 10921931 PMCID: PMC87116 DOI: 10.1128/jcm.38.8.2807-2813.2000] [Citation(s) in RCA: 46] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
To date the true prevalence of hepatitis C virus (HCV) mixed-genotype infections has not been established mainly because currently available methods are not suitable for the detection of mixed genotypes in a viral population. A novel semiautomated genotyping method, primer-specific and mispair extension analysis (S-PSMEA), which is more reliable than other genotyping assays was developed for detection of HCV mixed-genotype infections. A genotype present at levels as low as 0.8% in a defined mix of HCV genotypes was detected, showing a 20-fold increase in sensitivity over that of direct DNA sequencing. A total of 434 HCV isolates were genotyped and analyzed for a comparative study of the accuracy between S-PSMEA and four current genotyping methods. The results showed that viruses in approximately 40% of the samples from this group determined to be infected with mixed genotypes by S-PSMEA were undetected by direct DNA sequencing due to its low sensitivity. Type-specific PCR, line probe assay, and restriction fragment length polymorphism analysis performed poorly, being able to identify only 38.5, 16.1, and 15.4% of mixed-genotype infections, respectively, that were detected by direct DNA sequencing. The prevalence of mixed-genotype infections detected by S-PSMEA was 7.9% (12 of 152 donors) among HCV-infected blood donors, 14.3% (15 of 105) among patients with chronic hepatitis C, and 17.1% (6 of 36) among thalassemia patients who had received multiple transfusions. The data lead us to conclude that HCV mixed-genotype infections are more common than previously estimated and that S-PSMEA may be the method of choice when detection of genotypes present at low levels in mixed-genotype infections is required due to its higher level of sensitivity.
Collapse
|
23
|
Akçetin Z, Busch A, Kessler G, Heynemann H, Holtz J, Brömme HJ. Evidence for only a moderate lipid peroxidation during ischemia-reperfusion of rat kidney due to its high antioxidative capacity. UROLOGICAL RESEARCH 1999; 27:280-4. [PMID: 10460900 DOI: 10.1007/s002400050124] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
The extent of lipid peroxidation after ischemia-reperfusion (I-R) injury in rat kidney has been controversial. After I, xanthine oxidase (XO) is thought to be the main oxygen radical-generating system and malondialdehyde (MDA) is considered to be a marker of lipid peroxidation (LPO). In young rats (10 weeks old) a unilateral warm I of 40 and 60 min duration with subsequent R up to 1 h was conducted. Beside the "footprints" of oxidative stress, the cytosolic antioxidative capacity, expressed as superoxide anion (SOA) scavenging capacity, and the renal catalase were also investigated. There was only a moderate and transient increase of renal MDA 5 and 10 min after the onset of reoxygenation (133.57/70. 67 and 97.84/91.57 vs. 49.47 nmol/g ww in preischemic controls). ATP breakdown (to 83/65 from 2947 nmol/g ww) with consecutive accumulation of hypoxanthine (up to 1105 nmol/g ww) at the end of ischemic period and the subsequent rapid decline of hypoxanthine by XO during reperfusion were used for an assessment of the SOA-generating capacity of these kidneys. Superoxide dismutase (SOD) activity, glutathione (GSH) and the high activity of catalase (18000 U/g ww) remained nearly unchanged during R. Only 1/25-1/50 of the kidney cytosol was able to scavenge the whole amount of SOA generated by the total XO activity of rat kidney. Thus, it could be analytically and stoichiometrically shown that after IR there is only a moderate oxidative stress in kidneys of young rats; this is due to their high SOA-scavenging capacity compared with their SOA-generating ability.
Collapse
|
24
|
Collier JD, Zanke B, Moore M, Kessler G, Krajden M, Shepherd F, Heathcote J. No association between hepatitis C and B-cell lymphoma. Hepatology 1999; 29:1259-61. [PMID: 10094973 DOI: 10.1002/hep.510290422] [Citation(s) in RCA: 88] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Chronic viral infection has been implicated in the pathogenesis of B-cell lymphoma, and hepatitis C virus (HCV) infects lymphocytes. Chronic infection with HCV may result in B-cell proliferation. Individuals infected with hepatitis C are often co-infected with the RNA virus GB virus type C. Studies from Europe where hepatitis C infection is more common than in North America have shown a high prevalence of hepatitis C infection in patients with B-cell lymphoma. The aim of this study was to establish the prevalence of HCV and GBV-C infection in patients with B-cell lymphoma in an area of low HCV prevalence. One hundred patients with B-cell lymphoma (10 high grade, 46 intermediate grade, and 44 low grade) and 100 controls with nonhematological malignancies were studied. Serum was analyzed for HCV antibodies by third generation enzyme-linked immunosorbant assay, and HCV RNA and GBV-C RNA was analyzed by reverse transcriptase PCR. None of the controls or lymphoma patients had antibodies to HCV. HCV RNA was undetected in 60 out of 100 lymphoma patients tested. GBV-C RNA was detected in the serum of 5 out of 100 (5%) of lymphoma patients and in 3 out of 100 (3%) controls. Hepatitis C and GBV-C are, therefore, unlikely to play a major role in the pathogenesis of B-cell lymphoma in North America.
Collapse
|
25
|
Hu YW, Balaskas E, Kessler G, Issid C, Scully LJ, Murphy DG, Rinfret A, Giulivi A, Scalia V, Gill P. Primer specific and mispair extension analysis (PSMEA) as a simple approach to fast genotyping. Nucleic Acids Res 1998; 26:5013-5. [PMID: 9776770 PMCID: PMC147926 DOI: 10.1093/nar/26.21.5013] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
A simple method, primer specific and mispair extension analysis (PSMEA) with pfu DNA polymerase was developed for genotyping. PSMEA is based on the unique properties of 3'-->5' exonuclease proofreading activity. In the presence of an incomplete set of dNTPs, pfu was found to be extremely discriminative in nucleotide incorporation and proofreading at the initiation step of DNA synthesis, completely preventing primer extension when mispair(s) are found adjacent to the 3'-end of the primer. This has allowed us to accurately detect nucleotide variations, deletions and insertions for fast genotyping.
Collapse
|