bluuebunny/crossref_metadata_2025_split huggingface dataset:
Menstrual cycle variation of apparent diffusion coefficients measured in the normal breast using MRI
Authors: Partridge Savannah C. , McKinnon Graeme C. , Henry Roland G. , Hylton Nola M. 
Published: August 2002

AbstractRecent investigations have shown that tumors may be distinguished from benign lesions in the breast based on differences in apparent diffusion coefficient (ADC) values. The goal of this study was to assess the magnitude of normal variations in the measured ADC of breast parenchyma during the menstrual cycle. Eight healthy female subjects were scanned once a week for 4 weeks, using a diffusion‐weighted single‐shot fast spin‐echo (DW‐SSFSE) sequence. The ADC of breast fibroglandular tissue was calculated for each woman at each time point. Results showed a trend of decreased ADC during the second week of the cycle, and increased ADC during the final week. However, no significant influence of menstrual cycle on breast ADC values was identified. The results of this study show that the normal fluctuation of breast ADC is relatively small, and the coefficient of variation was determined to be 5.5% for our group of volunteers during a menstrual cycle. Nonetheless, breast diffusion measurements for tumor differentiation and evaluation of treatment response should be interpreted with consideration of normal variability. J. Magn. Reson. Imaging 2001;14:433–438. © 2001 Wiley‐Liss, Inc.
Electrospray ionization tandem mass spectrometric study of salt cluster ions: Part 2 — Salts of polyatomic acid groups and of multivalent metals
Authors: Hao Chunyan , March Raymond E. 
Published: August 2002

AbstractSalt cluster ions formed from 0.05 M solutions of CaCl2, CuCl2 and NaAB (where A = 1 or 2 and B = CO32−, HCO3−, H2PO4− and HPO42−) were studied by electrospray ionization tandem mass spectrometry. The effects on salt cluster ions of droplet pH and of redox reactions induced by electrospray provide information on the electrospray process. CaCl2 solution yielded salt cluster ions of the form (CaCl2)n(CaCl)xx+ and (CaCl2)n(Cl)yy−, where x, y = 1–3, in positive‐ and negative‐ion modes, respectively. Upon collision induced dissociation (CID), singly charged CaCl2 cluster ions fragmented, doubly charged cluster ions generated either singly or both singly and doubly charged fragment ions, depending on the cluster mass, and triply charged clusters fragmented predominantly by the loss of charged species. CuCl2 solution yielded nine series of cluster ions of the form (CuCl2)n(CuCl)m plus Cu+, CuCl+, or Cl−. CuCl, the reductive product of CuCl2, was observed as a neutral component of positively and negatively charged cluster ions. Free electrons were formed in a visible discharge that bridged the gap between the electrospray capillary and the sampling cone brought about the reduction of Cu2+ to Cu+. Upon CID, these cluster ions fragmented to lose CuCl2, CuCl, Cl, and Cl2. Na2CO3 and NaHCO3 solutions yielded cluster ions of the form (Na2CO3)n plus Na+ or NaCO3−. Small numbers of NaHCO3 molecules were found in some cluster ions obtained with the NaHCO3 solution. For both Na2HPO4 and NaH2PO4 solutions, ions of the form (Na2HPO4)h, (NaH2PO4)i, (Na3PO4)j, (NaPO3)k plus Na+, PO3− or H2PO4− were observed. In addition, ions having one or two phosphoric acid (H3PO4) molecules were observed from the NaH2PO4 solution while ions containing one sodium hydroxide (NaOH) molecule were observed from the Na2HPO4 solution.The cluster ions observed from these four salts of polyatomic acid groups indicate that changes in pH occur in both directions during the electrospray process principally by solvent evaporation; the pH value of the acidic solution became lower and that of the basic solution higher. Copyright © 2001 John Wiley & Sons, Ltd.
Simultaneous determination of all‐trans, 9‐cis, 13‐cis retinoic acid and retinol in rat prostate using liquid chromatography–mass spectrometry
Authors: Wang Yan , Chang William Y. , Prins Gail S. , van Breemen Richard B. 
Published: August 2002

AbstractSince retinoic acid (RA) and RA receptors are key developmental regulators during organogenesis, they might participate in the abnormal development of the prostate caused by early estrogen exposure. In order to test this assumption, a sensitive analytical method that can differentiate 9‐cis, 13‐cis, and all‐trans RA in small tissue samples (∼8 mg) is required. Since retinol is the metabolic precursor to RA, simultaneous quantification of retinol would also provide valuable information. Here, we report a liquid chromatography–mass spectrometry method for simultaneous determination of retinol and 9‐cis, 13‐cis, and all‐trans RA in rat prostate. Mass spectrometric signal responses for RA were compared using positive ion atmospheric‐pressure chemical ionization (APCI) and electrospray, as well as positive ion and negative ion APCI. Positive ion APCI was selected for all subsequent analysis for its better sensitivity, and to provide simultaneous determination of retinol and RA. Ventral prostate tissue samples were homogenized and extracted following simple protein precipitation without derivatization. Baseline separation of 9‐cis, 13‐cis, and all‐trans RA standards was obtained by using a non‐porous silica C18 column. Selected ion monitoring of the ions m/z 301 and m/z 269 was carried out for mass spectrometric quantitative analysis. The ion of m/z 301 corresponded to the protonated molecule of RA, whereas the ion of m/z 269 corresponded to loss of water or acetic acid from the protonated molecule of retinol or the internal standard retinyl acetate respectively. The method has a linear response over a concentration range of at least three orders of magnitude. The limit of quantitation was determined to be 702 fmol all‐trans RA injected on‐column. The method showed excellent intra‐ and inter‐assay reproducibility and good recovery, and is suitable for analyzing RA and retinol in small tissue samples (∼8 mg). Copyright © 2001 John Wiley & Sons, Ltd.
In vitro immunosuppressive activity of tacrolimus dihydrodiol precursors obtained by chemical oxidation and identification of a new metabolite of SDZ‐RAD by electrospray and electrospray‐linked scan mass spectrometry
Authors: Lhoëst G. , Hertsens R. , Verbeeck R. K. , Maton N. , Wallemacq P. , Dehoux J. P. , Latinne D. 
Published: August 2002

AbstractDifferent tacrolimus epoxides and dihydrodiol epoxides arising from the chemical oxidation of the parent drug are described. Open‐chain tautomeric forms involving the lactone function were identified for the tacrolimus epoxides. Moreover, the identification by electrospray and electrospray linked scan mass spectrometry of an SDZ‐RAD C16–C27 O‐demethyl 17, 18–19, 20–21, 22 tris‐epoxide new metabolite isolated from pig liver microsomes is reported. The in vitro immunosuppressive activity, using mixed lymphocyte reactions of the two macrolide reported oxidation compounds are discussed. Copyright © 2001 John Wiley & Sons, Ltd.
Elimination of 118 Da: a characteristic fragmentation in the tandem mass spectra of 11(15 → 1)‐abeo‐taxanes
Authors: Madhusudanan K. P. , Chattopadhyay S. K. , Srivastava S. 
Published: August 2002

AbstractThe mechanism of the elimination of 118 Da from 11(15→1)‐abeo‐taxanes was elucidated with the help of the tandem mass spectra of [M + NH4]+ and [M + Li]+ ions and the corresponding D‐exchanged species. The fragmentation is triggered by the initial loss of the C‐10 substituent. Evidence was also obtained for the stepwise elimination of acetone and acetic acid. Acetone is eliminated from the C‐1 hydroxyisopropyl group and acetic acid from either the C‐9 or C‐7 acetoxy groups. The presence of an additional acetoxy group at C‐13 leads to the direct elimination of 118 Da from [M + NH4]+ and [M + Li]+ ions involving the C‐13 acetoxy group. Copyright © 2001 John Wiley & Sons, Ltd.
Risk factors of hepatitis C virus‐related liver cirrhosis in young adults: Positive family history of liver disease and transporter associated with antigen processing 2 (TAP2) *0201 Allele
Authors: Akuta Norio , Chayama Kazuaki , Suzuki Fumitaka , Someya Takashi , Kobayashi Masahiro , Tsubota Akihito , Suzuki Yoshiyuki , Saitoh Satoshi , Arase Yasuji , Ikeda Kenji , Kumada Hiromitsu 
Published: August 2002

AbstractThe aim of this study was to clinically characterize young patients with hepatitis‐C‐related cirrhosis. We compared 27 patients with liver cirrhosis (Group LC) who were anti‐HCV positive, aged 40 years or less at the time of diagnosis, with 323 consecutive patients with HCV‐related chronic hepatitis (Group CH) matched for age and gender. Furthermore, Group LC was divided into two arbitrary groups (29–35 years, n = 8 /36–40 years, n = 19), based on the age of patients at the time of diagnosis of liver cirrhosis. Patients' characteristics and family history were investigated, and the frequency of transporter associated with antigen processing 2 (TAP2) was determined. A family history of liver disease was present in 40.7% of Group LC but in 18.0% of Group CH (P < 0.05). The younger the age of diagnosis of cirrhosis in Group LC, the higher the frequency of a positive family history (29–35 years, 87.5%; 36–40 years, 21.1%, P < 0.05). The frequency of TAP2*0201 was significantly higher in young adult patients with HCV‐related liver cirrhosis than in HCV carriers with normal ALT (P < 0.05), and tended to be higher than in uninfected normal subjects (P = 0.05). The cumulative survival rate of cirrhosis patients with family history of liver diseases was significantly lower than that of cirrhosis patients without such history (P < 0.05). Our findings suggest that a positive family history of liver disease and TAP2*0201 polymorphism may be risk factors for HCV‐related liver cirrhosis in young adults. J. Med. Virol. 64:109–116, 2001. © 2001 Wiley‐Liss, Inc.
TT virus detection in oral lichen planus lesions
Authors: Rodríguez‐Iñigo Elena , Arrieta Juan José , Casqueiro Mercedes , Bartolomé Javier , López‐Alcorocho Juan Manuel , Ortiz‐Movilla Nuria , Manzarbeitia Félix , Pardo Margarita , Carreño Vicente 
Published: August 2002

AbstractEpidemiological studies have demonstrated a correlation between oral lichen planus and different liver diseases. The new virus termed TT virus (TTV) is highly prevalent in patients with chronic hepatitis of different etiology and it may be speculated that TT virus may be involved in the pathogenesis of oral lichen planus. This study examined the presence of TT virus DNA in serum by PCR and in oral mucosa biopsies by in situ hybridization from 20 patients with oral lichen planus (13 with chronic hepatitis and seven without liver disease). Serum and oral mucosa biopsies from six patients all with chronic hepatitis with leukoplakia were also studied as controls. TT virus DNA was positive in the serum of 17/20 (85%) of the patients with oral lichen planus and in all the controls. TT virus DNA hybridization signals were detected in mucosa biopsies from all the patients with TT virus DNA in serum but in none of the three cases without this marker. The percentage of positive cells ranged from 1.6–80%. No differences were found in the percentage of positive cells between TT virus positive patients with and without oral lichen planus and there was no relationship between the number of positive cells and the intensity of the inflammatory infiltrate. In conclusion, TT virus infects oral epithelial cells but the results do not support a role for TT virus in causing oral lichen planus. J. Med. Virol. 64:183–189, 2001. © 2001 Wiley‐Liss, Inc.
Epstein‐Barr virus involvement is mainly restricted to lymphoepithelial type of gastric carcinoma among various epithelial neoplasms
Authors: Kijima Yuko , Hokita Shuichi , Takao Sonshin , Baba Masamichi , Natsugoe Shoji , Yoshinaka Heiji , Aridome Kuniaki , Otsuji Tatsuto , Itoh Tetsuhiko , Tokunaga Masayoshi , Eizuru Yoshito , Aikou Takashi 
Published: August 2002

AbstractTo demonstrate the association of Epstein‐Barr virus (EBV) with primary epithelial neoplasms in the south part of Kyushu, Japan, 761 carcinomas consisting of 75 lung, 61 breast, 107 esophagus, 102 colon, 58 pancreas, 45 thyroid, and 313 gastric cancers were examined by EBER‐1 in situ hybridization. EBER‐1 was detected in 23 cases (7.3%) out of 313 gastric carcinomas, while none of the other carcinomas was positive for EBER‐1. Twenty‐eight (9.4%) out of 313 gastric carcinomas were differentiated poorly to moderately carcinomas with prominent lymphoid cell infiltration, similar to so‐called lymphoepithelioma‐like carcinoma, and 19 cases (67.9%) were positive for EBER‐1. Although two (2.6%) and 11(10.3%) out of 75 lung and 107 esophagus carcinomas were so‐called lymphoepithelioma‐like carcinomas, respectively, but EBER‐1 was not detected in other epithelial neoplasms that originated from the lung, esophagus, breast, colon, pancreas, and thyroid in the south of Kyushu, Japan. As a result, EBV was associated with only some gastric carcinomas but not with other epithelial neoplasms originating from the lung, esophagus, breast, colon, pancreas, and thyroid in southern Japan. J. Med. Virol. 64:513–518, 2001. © 2001 Wiley‐Liss, Inc.
Antiretroviral treatment monitoring with an improved HIV‐1 p24 antigen test: an inexpensive alternative to tests for viral RNA
Authors: Schüpbach Jörg , Böni Jürg , Flepp Markus , Tomasik Zuzana , Joller Helen , Opravil Milos 
Published: August 2002

AbstractMonitoring of viral RNA has become indispensable for the management of HIV‐1 infection, but is expensive. This study investigated whether a highly improved test for p24 antigen could serve as an alternative. Thirty‐four patients enrolled during 1997 into two treatment studies were tested prospectively for viral RNA by the Roche HIV‐1 Monitor® and for p24 antigen using signal‐amplification–boosted ELISA of heat‐denatured plasma. P24 antigen was detectable in 75.8% of 178 samples and HIV RNA in 73.9% of 138 samples. The half‐life of p24 antigen in the first phase of effective treatment was 1.6 ± .4 days (RNA, 1.7 ± .8). An apparent second, slower decay phase had a half‐life of 42 ± 16 days. Treatment failure occurred in 14 patients. Secondary treatment failures with RNA rebounds from undetectable levels to ≤ 103 copies/ml in two patients with an undetectable viral load and 103 HIV RNA copies/ml, respectively, at baseline were not detected by p24 antigen but carried a low risk for secondary resistance mutations. The other 12 failures were on average detected 29 days earlier by p24 antigen than by RNA (P = .0204), owing to slightly more frequent testing for p24 than for RNA (2.7 vs. 2.4 tests). Average costs for p24 antigen testing up to a failure were only 20.5% of those for RNA (P < .0001). These results indicate that heat‐denatured, amplification‐boosted p24 antigen measurement can be used as a simple and inexpensive alternative to HIV RNA testing for monitoring treatment. J. Med. Virol. 65:225–232, 2001. © 2001 Wiley‐Liss, Inc.
Antibodies against human papillomavirus (HPV) type 16 and 18 E2, E6 and E7 proteins in sera: Correlation with presence of papillomavirus DNA
Authors: Rosales Ricardo , López‐Contreras Mario , Cortes Roberto Risco 
Published: August 2002

AbstractHuman papillomavirus (HPV) infection is associated with cervical cancer. The E2 and E1 papillomavirus proteins are expressed at the early stage of infection and regulate DNA replication. The E2 protein activates and represses transcription from different HPVs promoters. At some stage when viral DNA gets integrated into the cellular genome, the E2 gene is disrupted or inactivated. This event leads to a derepression of the E6 and E7 viral oncogenes. These viral proteins are required normally for the maintenance of the malignant phenotype. Therefore, the E2, E6, and E7 proteins are present in all patients infected by papillomavirus. In this study, the association of antibody levels against E2, E6, and E7 proteins of HPV types 16, 18, and 6 was determined in relation to the presence of HPV DNA at the initial stages of HPV infection. Serum samples from 172 women with HPV infection, determined by Papanicolau (Pap) smears and colposcopy, were tested. Elevated antibody titers against E2 protein from the HPV 6 and HPV 16 were detected in 46.42 and 66.96% of the patients, respectively. Antibodies against the E7 and E6 proteins of HPV 16 were found in 51.78 and 36.60% of the patients, respectively. Antibodies against the E6 and E7 proteins of HPV 18 were 35 and 45%, respectively. A statistical difference was found for antibody titers against the E2, E6, and E7 proteins between patients with papillomavirus DNA and controls cases who had no cytological abnormalities and no HPV DNA. Sera titers were 1/500 for patients HPV positive and 1/50 for control individuals. Antibodies titers against E6 and E7 proteins were also examined in patients at 6 and 24 months after cryosurgery. In these patients, a slight decrease in the antibody level against the E2, E6, and E7 proteins was found. No correlation was found between age and number of sexual partners, with serum positivity to the E2, E6, and E7 papillomavirus proteins. These data suggest that antibodies against the E2, E6, and E7 proteins are good candidates for use as markers for monitoring cervical HPV infections. J. Med. Virol. 65:736–744, 2001. © 2001 Wiley‐Liss, Inc.
Transport and budding at two distinct sites of visible nucleocapsids of West Nile (Sarafend) Virus
Authors: Ng M.L. , Tan S.H. , Chu J.J.H. 
Published: August 2002

AbstractIt has been difficult to detect and visualize the physical nucleocapsid particles during the replication process of the flaviviruses. The use of cryo‐immunoelectron microscopy has clearly revealed the capsid proteins and nucleocapsid particles of West Nile (Sarafend) virus (a flavivirus) for the first time. Physical nucleocapsid particles accumulated in large numbers from 8 hr postinfection. Double immunolabeling of the envelope and capsid proteins showed a close association of these structural proteins for most of the replication cycle. By 10 hr postinfection, budding of nucelocapsids from the plasma membrane was very obvious. Although maturation at the plasma membrane was the dominant mode, during late infection, intracellular maturation into large vacuoles was also observed. J. Med. Virol. 65:758–764, 2001. © 2001 Wiley‐Liss, Inc.
Clinical significance of a highly sensitive enzyme immunoassay of hepatitis B surface antigen using a novel electron spin resonance technique
Authors: Aoki Masanori , Saito Takafumi , Watanabe Hisayoshi , Matsuo Taku , Saito Koji , Togashi Hitoshi , Kawata Sumio , Ishikawa Kazuyoshi , Aoyama Masaaki , Kamada Hitoshi , Shinzawa Haruhide 
Published: August 2002

AbstractWe developed a highly sensitive enzyme immunoassay (EIA), the p‐AP/HHTIO method, that detects serum hepatitis B surface antigen (HBsAg) by measuring stabilized nitroxide radicals using a novel electron spin resonance technique [Matsuo et al. (1998) Free Radic Biol Med 25:929–935]. To demonstrate the clinical significance of this method and to reveal occult hepatitis B virus (HBV) infection in patients, we used the method to analyze serum samples of 30 patients with acute or fulminant hepatitis who were negative for HBsAg by standard EIA, and those of seven chronic HBV carriers who became negative for HBsAg during a follow‐up period by standard EIA. We also examined serum HBV DNA by amplification of the HBV S gene, using the polymerase chain reaction (PCR) technique. The p‐AP/HHTIO method showed that 9 of 20 (45%) patients with acute hepatitis and 2 of 10 (20%) with fulminant hepatitis were positive for HBsAg; PCR detected HBV DNA in these HBsAg‐positive patients. Antibody against hepatitis B core antigen was detected in one patient with fulminant hepatitis. The p‐AP/HHTIO method demonstrated prolonged seropositivity of HBsAg even after standard EIA showed a loss of HBsAg in all seven HBV carriers. Our p‐AP/HHTIO method is useful for screening and diagnosing HBV infection in patients with liver diseases who are negative for conventional HBV‐related serological markers. J. Med. Virol. 66:166–170, 2002. © 2002 Wiley‐Liss, Inc.
Baculovirus expression of erythrovirus V9 capsids and screening by ELISA: Serologic cross‐reactivity with erythrovirus B19
Authors: Heegaard Erik D. , Qvortrup Klaus , Christensen Jesper 
Published: August 2002

AbstractDiagnosis of erythrovirus B19 (B19) relies on serology and the detection of viral DNA. Recently, a distinct erythrovirus isolate termed V9, markedly different from erythrovirus B19 (> 11% nucleotide disparity), was isolated. Standard B19 PCR assays were inconclusive and serologic tests failed to categorize V9 as an acute B19‐like infection. Sequencing, combined with PCR studies, have since demonstrated the need for specific and differentiated techniques when examining samples for possible B19 or V9 viremia. The antigenic properties of the V9 capsid proteins have not been characterized previously. To address this question, V9 VP1 and VP2 open reading frames were cloned and expressed in insect cells using a baculovirus vector. Large quantities of purified recombinant V9 capsid protein were produced and electron micrographs revealed self‐assembly of V9 VP1/VP2 and VP2 capsids into empty icosahedral erythrovirus‐like particles with a diameter of ≈23 nm. Screening of a panel of 270 clinical samples for the presence of V9 IgM and IgG antibodies in ELISA showed 100% serologic cross‐reactivity between B19 and V9 when comparing V9 VP2 capsids to a commercial B19 VP2 assay. This suggests that both a V9 and a B19 antibody response may be diagnosed equally well by ELISA using either V9 or B19 recombinant capsids as antigen source. Retrospectively, translation of the V9 sequence indicates that despite a significant genetic variation on the DNA level, the majority of the discrepant DNA sequence represents silent mutations leading to an amino acid sequence very similar to the known B19 strains (96–97% homology). J. Med. Virol. 66:246–252, 2002. © 2002 Wiley‐Liss, Inc.
Evidence of lytic infection of Epstein‐Barr virus (EBV) in EBV‐positive gastric carcinoma
Authors: Hoshikawa Yoshiko , Satoh Yukio , Murakami Masanao , Maeta Michio , Kaibara Nobuaki , Ito Hisao , Kurata Takeshi , Sairenji Takeshi 
Published: August 2002

AbstractTwenty‐one cases of gastric carcinoma were tested for the presence of Epstein‐Barr virus (EBV) genome by polymerase chain reaction (PCR) analysis. EBV genome was detected in 3 (14%) of the 21 cases. In situ hybridization for EBV‐encoded small RNA 1 showed that EBV genomes were present in almost all carcinoma cells of the 3 cases. Southern hybridization for terminal repeats of the EBV‐DNA revealed that the cases carried an individual monoclonal EBV genome. The analysis demonstrated the presence of linear form of EBV‐DNA indicating lytic EBV infection in one of the cases. The expression of EBV genes in the cases was analyzed by reverse transcription‐PCR. The mRNA for EBV‐determined nuclear antigen (EBNA) initiating from the BamHI‐Q promoter was detected, while both BamHI‐W and ‐C promoters were not detected. EBNA2 and latent membrane protein (LMP) 1 mRNAs were not detected in all cases, while LMP2A mRNA was detected in 2 cases. The transcripts of EBV immediate‐early genes, BZLF1 and/or BRLF1 were detected in 2 of the cases. The transcripts of late lytic genes (BcLF1 and BLLF1) were detected partly in the 3 cases. Our results indicate that lytic EBV infection occurs in EBV‐positive gastric carcinomas. J. Med. Virol. 66:351‐359, 2002. © 2002 Wiley‐Liss, Inc.