bluuebunny/crossref_metadata_2025 huggingface dataset:
Synthesis of two novel oxocyclam‐binding technetium complexes containing an analogue of cocaine
Authors: Turpin F. , Masri F. , Riché F. , Berthommier E. , Emond P. , Vidal M. , Auzeloux P. , Loc'h C. , Neuquelman N. , Mauclaire L.
Published: August 2002

In order to visualize and quantify dopamine transporters, the synthesis of two novel ligands labelled with technetium‐99 m (99mTc) has been investigated. A multi‐step synthesis afforded two target ligands with a tropane skeleton and a macrocyclic complexing moiety. The choice and the position of substituents are in adequation with dopamine transporter structure. The radiolabelling of these ligands with 99mTc has been studied and the results make them good candidates for SPECT imaging. Copyright © 2002 John Wiley & Sons, Ltd.
Chronological analysis of physiological T2* signal change in the cerebrum during breath holding
Authors: Nakada Kazuyoshi , Yoshida Daisuke , Fukumoto Mitsutaka , Yoshida Shoji
Published: August 2002

The purpose of this study was to examine which physiological factors affect cerebral T2* signal intensity (SI) during breath holding (BH) (apnea after inspiration and breathing after expiration) in normal volunteers. We examined SI changes caused by anoxic gas inhalation, by respiratory movements, and by BH. High‐speed echo planar images (EPI) showed changes in SI that could be divided into five phases. Reports indicate that SI changes induced by BH are due to the effects on the magnetic susceptibility of deoxygenated hemoglobin (deoxyhemoglobin (dHb)) and to hypercapnia, but these reports could not fully explain the observed five phases. In addition to deoxyhemoglobin susceptibility and hypercapnia, we found that respiratory movements play a third critical role in modifying SI by affecting blood flow into the region of interest (ROI), as judged from right carotid artery flow. Consequently, we propose that the physiological SI changes induced by BH are derived from blood oxygenation, hypercapnia, and respiratory movements. J. Magn. Reson. Imaging 2001;13:344–351. © 2001 Wiley‐Liss, Inc.
Challenges to interpretation of breast MRI
Authors: Kinkel Karen , Hylton Nola M.
Published: August 2002

This review describes the current knowledge and challenges of lesion interpretation with MRI of the breast according to different image interpretation strategies. Particular emphasis is given to patient‐ and tumor‐related factors that influence image interpretation. The impacts of the menstrual cycle, prior surgery, radiation therapy, and chemotherapy are summarized. Particular enhancement features of ductal carcinoma in situ (DCIS) or invasive lobular carcinoma are described. Finally, an adequate diagnosis at MRI of the breast should take into account the results of the patient's history, physical examination, and all imaging tests performed before MRI. J. Magn. Reson. Imaging 2001;13:821–829. © 2001 Wiley‐Liss, Inc.
The impact of navigator timing parameters and navigator spatial resolution on 3D coronary magnetic resonance angiography
Authors: Spuentrup Elmar , Stuber Matthias , Botnar René M. , Manning Warren J.
Published: August 2002

The impact of navigator spatial resolution and navigator evaluation time on image quality in free‐breathing navigator‐gated 3D coronary magnetic resonance angiography (MRA), including real‐time motion correction, was investigated in a moving phantom. Objective image quality parameters signal‐to‐noise ratio (SNR) and vessel sharpness were compared. It was found that for improved mage quality a short navigator evaluation time is of crucial importance. Navigator spatial resolution showed minimal influence on image quality. J. Magn. Reson. Imaging 2001;14:311–318. © 2001 Wiley‐Liss, Inc.
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

Recent 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

Salt 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

Since 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

Different 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

The 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

The 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

Epidemiological 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

To 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

Monitoring 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

Human 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

It 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

We 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

Diagnosis 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

Twenty‐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.
Transmission of SEN virus from mothers to their babies
Authors: Pirovano Silvia , Bellinzoni Marco , Ballerini Cristina , Cariani Elisabetta , Duse Marzia , Albertini Alberto , Imberti Luisa
Published: August 2002

Sera from 30 women at high risk for infection, one half of which were SEN virus positive (SENV+), were collected at delivery to study SENV mother‐to child transmission. Thirteen of their babies were positive for at least one SENV strain: one baby was SENV+ at birth, eight became positive within 6 months from delivery, and four became positive in the following months. Our data indicate that vertical transmission of SENV does occur, presumably, at delivery, but it may not induce persistent viremia. This is supported by the fact that, generally, SENV is not detected at birth, by the high SENV homology in the sequences found in the mothers and in their children, by a lack of other risk factors for infection of the babies, and by the irregular detection of SENV in the follow‐up. No clinical events surely linked to SENV infection were found, but transient elevations of alanine aminotransferase were observed in babies followed for a long period of time. J. Med. Virol. 66:421‐427, 2002. © 2002 Wiley‐Liss, Inc.
Detection of varicella‐zoster virus DNA in throat swabs of patients with herpes zoster and on air purifier filters
Authors: Suzuki Kayoko , Yoshikawa Tetsushi , Tomitaka Akiko , Suzuki Kyoko , Matsunaga Kayoko , Asano Yoshizo
Published: August 2002

Zoster patients are considered to be less contagious than those with varicella because their infectious lesions are localized. However, it is not known when the spread of varicella‐zoster virus (VZV) from zoster patients begins, how long it continues, and how far the virus spreads from the zoster patients. Twelve cases of hospitalized zoster patients were studied. The polymerase chain reaction (PCR) was used to detect VZV DNA in samples taken from the surface of their eruptions, throats, and the air purifier filters in their rooms. In all patients, VZV DNA was detected in the samples from eruptions. VZV DNA was detected in 8 of 12 patients from the throats. VZV DNA was detected for 9 of 12 patients from the filter samples. This study shows the possibility of a wide distribution of VZV DNA to the environment from infected patients. VZV may be excreted from cutaneous eruptions or from the throats of patients. J. Med. Virol. 66:567–570, 2002. © 2002 Wiley‐Liss, Inc.
Space–time wavelet expansion iterative solution of non‐uniform transmission lines with arbitrary loads
Authors: Barmada S. , Raugi M.
Published: August 2002

In this paper a method based on the double expansion by wavelet on the interval in space and time of non‐uniform transmission line equations with arbitrary loads is presented. The differential time domain equations are transformed into a Lyapunov equation which is adaptively solved. Hence, a Fourier‐like approach for the time‐domain solution of transient electromagnetics problems is obtained avoiding the typical problems of time‐stepping techniques. The accuracy of the solution can be selected by choosing an adequate number of components of the wavelet basis. Different cases have been studied to show the effectiveness of the method. Copyright © 2001 John Wiley & Sons, Ltd.
An extended Huygens' principle for modelling scattering from general discontinuities within hollow waveguides
Authors: Ferrari Ronald L.
Published: August 2002

The modal fields, generalized scattering matrix (GSM) theory and dyadic Green's functions relating to a general uniform hollow waveguide are briefly reviewed in a mutually consistent normalization. By means of an analysis linking these three concepts, an extended version of the mathematical expression of Huygens' principle is derived, applying to scattering from an arbitrary object within a hollow waveguide. The integral‐equation result expresses the total field in terms of the incident waveguide modal fields, the dyadic Green's functions and the tangential electromagnetic field on the surface of the object. It is shown how the extended principle may be applied in turn to perfect conductor, uniform material and inhomogeneous material objects using a quasi method of moments (MM) approach, coupled in the last case with the finite element method. The work reported, which indicates how the GSM of the object may be recovered, is entirely theoretical but displays a close similarity with established MM procedures. Copyright © 2001 John Wiley & Sons, Ltd.
Influence of antioxidants on the blood‐brain barrier permeability during epileptic seizures
Authors: Öztaş Baria , Kılıç Şehri , Dural Esen , İspir Turgay
Published: August 2002

Pentylenetetrazol‐induced seizures in rats lead to the breakdown of the blood‐brain barrier. We compared the disruption of the blood‐brain barrier during epileptic seizure in untreated rats and in rats treated with vitamin E or selenium. The rats were supplemented with nontoxic doses of sodium selenite (4 pp) in drinking water for 3 months, or vitamin E (70 mg/kg) was given intraperitoneally for 30 min before the pentylenetetrazole injection. Evans‐blue was used as a blood‐brain barrier tracer and was given intravenously at a dose of 4 ml/kg of a 2% solution. The rats were divided into four experimental groups. Group I: control (n = 24); Group II: pentylenetetrazole‐induced seizure (n = 12); Group III: vitamin E injected + seizure (n = 12); Group IV: Selenium supplemented + seizure (n = 12). The rats subjected to epileptic seizures showed Evans‐blue albumin extravasations especially in the thalamic nuclei, brainstem, occipital, and frontal cortex. Mean values for Evans‐blue dye were found to be 0.28 ± 0.04 mg % brain tissue in control rats and 1.6 ± 0.2 mg % brain tissue after epileptic seizures (P < 0.01). The magnitude of distribution of the blood‐brain barrier during epileptic seizures was significantly less in rats treated with vitamin E or selenium. The mean value for Evans‐blue dye was found to be 1.2 ± 0.1 mg % brain tissue in selenium supplemented rats and 1.2 ± 0.1 mg % brain tissue in vitamin E injected rats after epileptic seizures. This difference between treated and untreated animals was found to be significant (P < 0.05). The findings of the present study suggest that free radicals contribute to disruption of the blood‐brain barrier during pentylenetetrazol‐induced seizures. J. Neurosci. Res. 66:674–678, 2001. © 2001 Wiley‐Liss, Inc.
Selective CC chemokine receptor expression by central nervous system‐infiltrating encephalitogenic T cells during experimental autoimmune encephalomyelitis
Authors: Fife Brian T. , Paniagua Mary C. , Lukacs Nicholas W. , Kunkel Steven L. , Karpus William J.
Published: August 2002

Experimental autoimmune encephalomyelitis (EAE) is a CD4+ T cell disease of the central nervous system (CNS) characterized by mononuclear cell infiltration, demyelination, and paralysis. Recent studies describing the relationship of chemokine expression with development of clinical disease have led to the hypothesis that distinct chemokine receptors corresponding to specific ligands are expressed by CNS‐infiltrating antigen‐specific encephalitogenic T cells as well as host‐derived bystander T cells and monocytes. In an effort to study encephalitogenic T cell chemokine receptor expression, we examined CC chemokine receptor expression from resting, activated, and CNS‐isolated CD4+ T cells. CCR1, CCR2, CCR3, CCR5, CCR6, CCR7, and CCR8 mRNA is expressed by normal CD4+ T cells. In vitro activated T cells expressed CCR1, CCR2, CCR3, CCR5, CCR6, CCR7, and CCR8 mRNA as well as CCR4. After EAE induction, CCR1 mRNA was expressed by donor‐derived encephalitogenic and host‐derived CD4+ T cells isolated only from CNS and not from spleen. In vivo neutralization of the CCR1 ligand, macrophage inflammatory protein‐1α (CCL3), resulted in less encephalitogenic CD4+ T cell CNS infiltration. These results demonstrate the importance of CC chemokine receptor expression by CD4+ encephalitogenic T cells for CNS infiltration and subsequent disease development. J. Neurosci. Res. 66:705–714, 2001. © 2001 Wiley‐Liss, Inc.
Pyruvate carboxylation in neurons
Authors: Hassel Bjørnar
Published: August 2002

Carboxylation of pyruvate in the brain was for many years thought to occur only in glia, an assumption that formed much of the basis for the concept of the glutamine cycle. It was shown recently, however, that carboxylation of pyruvate to malate occurs in neurons and that it supports formation of transmitter glutamate. The role of pyruvate carboxylation in neurons is to ensure tricarboxylic acid cycle activity by compensating for losses of α‐ketoglutarate that occur through release of transmitter glutamate and GABA; these amino acids are α‐ketoglutarate derivatives. Available data suggest that neuronal pyruvate carboxylation is quantitatively important. But because there is no net CO2 fixation in the brain, pyruvate carboxylation must be balanced by decarboxylation of malate or oxaloacetate. Such decarboxylation occurs in both neurons and astrocytes. Several in vitro studies have shown a neuroprotective effect of pyruvate supplementation. Pyruvate carboxylation may be one mechanism through which such treatment is effective, because pyruvate carboxylation through malic enzyme is active during energy deficiency and leads to an increase in the level of dicarboxylates that can be metabolized through the tricarboxylic acid cycle for ATP production. © 2001 Wiley‐Liss, Inc.
Light‐induced changes in glutamate release from isolated rat retina is regulated by cyclic guanosine monophosphate
Authors: Barabás Péter , Kovács Ilona , Kovács Richárd , Pálhalmi János , Kardos Julianna , Schousboe Arne
Published: August 2002

Isolated rat retina was preloaded with [14C]glutamate and subsequently superfused to follow release of glutamate (Glu). After 20 min of superfusion in the dark, exposure of the [14C]Glu preloaded rat retina to a single train of white light pulses reduced Glu efflux significantly in the absence as well as in the presence of low (4 μM) and high (0.5 mM) concentrations of the Glu uptake inhibitor trans‐L‐pyrrolidine‐2,4‐dicarboxylate (t‐PDC). The dark–light response was the highest in the presence of 4 μM t‐PDC by establishing a plateau at 75% ± 7% of the tonic Glu release in the dark (100%). Displaying transient to saturating responses with increasing relative luminance, time series of four trains of white light pulses arrived at a plateau of 85% ± 10%. The cyclic guanosine monophosphate (cGMP) phosphodiesterase inhibitor Zaprinast (200 μM) antagonized the effect of the light series, leading to a plateau of 115% ± 9%. Exposure of the retina to the guanylyl cyclase inhibitor LY83583 (30 and 100 μM) showed fast, transient responses characterized by peaks at 90% ± 1% and 80% ± 3%, respectively. © 2002 Wiley‐Liss, Inc.
Ultrastructural localization of neuropeptide Y Y1 receptors in the rat medial nucleus tractus solitarius: Relationships with neuropeptide Y or catecholamine neurons
Authors: Glass Michael J. , Chan June , Pickel Virginia M.
Published: August 2002

Neuropeptide Y (NPY) Y1 receptor (Y1‐R) agonists influence cardiovascular regulation. These actions may involve NPY‐ and catecholamine‐containing neurons in the medial nucleus of the solitary tract (mNTS), at the level of the area postrema. The cellular sites through which Y1‐R agonists may interact with NPY and catecholamines in the mNTS, however, are not known. To determine potential sites of action for Y1‐R agonists, and their relationship to NPY or catecholamines in the mNTS, we used electron microscopic immunocytochemistry for the detection of sequence‐specific antipeptide antisera against Y1‐R alone or in combination with antisera against NPY or the catecholamine‐synthesizing enzyme tyrosine hydroxylase (TH). Analyses were conducted in the rat mNTS, at the level of the area postrema. Y1‐R was found mainly in small unmyelinated axons and axon terminals but also in some somata and dendrites as well as a small number of glia. Within axon terminals, labeling for Y1‐R was often present on dense core vesicles and small synaptic vesicles as well as extrasynaptic areas of the plasmalemma. Some Y1‐R‐labeled terminals also contained NPY or TH, suggesting that agonists of Y1‐R may influence the release of NPY or catecholamines in the mNTS. In addition, Y1‐R was found in dendrites that received asymmetric excitatory‐type synapses from unlabeled axon terminals. Some of these dendrites contained NPY or TH, which indicates that Y1‐R may be targeted for functional activation within NPY‐ or catecholamine‐expressing neurons in the mNTS. These results demonstrate that Y1‐R is a presynaptic receptor in NPY‐ or catecholamine‐containing axon terminals within the mNTS as well as a postsynaptic receptor on NPY‐ or catecholamine‐containing neurons that are contacted by axon terminals that likely contain excitatory amino acid transmitters. Agonists of Y1‐R in the mNTS may thus affect cardiovascular regulation by modulating NPY, catecholamine, and excitatory amino acid transmission. © 2002 Wiley‐Liss, Inc.
Interleukin‐4, interleukin‐10, and interleukin‐1‐receptor antagonist but not transforming growth factor‐β induce ramification and reduce adhesion molecule expression of rat microglial cells
Authors: Wirjatijasa Florentina , Dehghani Faramarz , Blaheta Roman A. , Korf Horst‐Werner , Hailer Nils P.
Published: August 2002

The activity of microglial cells is strictly controlled in order to maintain central nervous system (CNS) immune privilege. We hypothesized that several immunomodulatory factors present in the CNS parenchyma, i.e., the Th2‐derived cytokines interleukin (IL)‐4 and IL‐10, interleukin‐1‐receptor‐antagonist (IL‐1‐ra), or transforming growth factor (TGF)‐β can modulate microglial morphology and functions. Microglial cells were incubated with IL‐4, IL‐10, IL‐1‐ra, TGF‐β, or with astrocyte conditioned media (ACM) and were analyzed for morphological changes, expression of intercellular adhesion molecule (ICAM)‐1, and secretion of IL‐1β or tumor necrosis factor (TNF)‐α. Whereas untreated controls showed an amoeboid morphology both Th2‐derived cytokines, IL‐1‐ra, and ACM induced a morphological transformation to the ramified phenotype. In contrast, TGF‐β‐treated microglial cells showed an amoeboid morphology. Even combined with the neutralizing antibodies against IL‐4, IL‐10, or TGF‐β ACM induced microglial ramification. Furthermore, ACM did not contain relevant amounts of IL‐4 and IL‐10, as measured by enzyme‐linked immunosorbent assay (ELISA). Flow cytometry showed that lipopolysaccharide (LPS)‐induced ICAM‐1‐expression on microglial cells was strongly suppressed by ACM, significantly modulated by IL‐4, IL‐10, or IL‐1‐ra, but not influenced by TGF‐β. The LPS‐induced secretion of IL‐1β and TNF‐α was only reduced after application of ACM, whereas IL‐4 or IL‐10 did not inhibit IL‐1β‐ or TNF‐α secretion. TGF‐β enhanced IL‐1β‐ but not TNF‐α secretion. In summary, we demonstrate that IL‐4, IL‐10, and IL‐1‐ra induce microglial ramification and reduce ICAM‐1‐expression, whereas the secretion of proinflammatory cytokines is not prevented. TGF‐β has no modulating effects. Importantly, unidentified astrocytic factors that are not identical with IL‐4, IL‐10, or TGF‐β possess strong immunomodulatory properties. © 2002 Wiley‐Liss, Inc.
Protective effects of atypical antipsychotic drugs on PC12 cells after serum withdrawal
Authors: Bai Ou , Wei Zelan , Lu Wenfu , Bowen Rudy , Keegan David , Li Xin‐Min
Published: August 2002

Atypical antipsychotic drugs are widely used in the treatment of schizophrenia, and clinical evidence has shown that early and prolonged intervention with these drugs will improve the long‐term outcome. It is still unclear, however, whether the atypical antipsychotic drugs are also neuroprotective. To clarify this matter, we used PC12 cell cultures and the MTT assay for cell viability to determine whether various concentrations of the atypical antipsychotics clozapine, quetiapine, and risperidone are neuroprotective after serum withdrawal. In addition, to explore the drugs' actions, Northern blot was used to examine the gene expression of SOD1 (Cu/Zn superoxide dismutase) and p75NTR (p75 neurotrophin receptor). The results demonstrated that 1) the antipsychotic drugs can protect PC12 cells from death after serum withdrawal; cell viability in these drug treatment groups is significantly different from that in the groups without serum in the medium (P < 0.01); and 2) these drugs up‐regulated the SOD1 gene expression to more than 120% (P < 0.05) and also down‐regulated p75NTR mRNA levels to less than 65% of their respective control values (P < 0.05). These findings suggest that the atypical antipsychotics clozapine, quetiapine, and risperidone may exert a neuroprotective function through the modulation of SOD1 and p75NTR expression. © 2002 Wiley‐Liss, Inc.
Distribution in ocular structures and optic pathways of immunocompetent and glial cells in an experimental allergic encephalomyelitis (EAE) relapsing model
Authors: Villarroya Henri , Klein Christophe , Thillaye‐Goldenberg Brigitte , Eclancher Françoise
Published: August 2002

Relapsing experimental allergic encephalomyelitis (EAE) was induced in DA rats and the ocular pathologic events were examined at the various phases of the illness. About 80% of EAE rats presented anterior uveitis (AU), even after complete EAE recovery. We studied the phenotype and localization of immunocompetent cells, the major histocompatibility complex (MHC) class I and II antigen expression, as well as the chemokine monocyte chemoattractant protein‐1 (MCP‐1) appearance. In control animals, there were many glial fibrillary acidic protein (GFAP)+ cells and OX42+ cells in the ciliary body, retina, optic nerve and chiasma. Except in retina, we observed constitutive MHC class I and II expression. During the EAE acute phase, there was up‐regulation of MHC class II and GFAP antigens in iris, ciliary body, limbus, and optic pathways. MHC class I and ED2 antigens were expressed in meninges and in the prechiasmatic cisterna, by cells which could have a role in immune surveillance. MCP‐1 mRNA was highly expressed in optic pathways during the acute phase and the protein was expressed by astrocytes, macrophages, and lymphocytes. During the relapsing phase, MCP‐1 was weakly expressed to disappear almost completely during the final recovery phase. The expression of MHC class II on astrocytes was increased during the relapsing and final recovery phase in which the inflammatory lesions persisted. These findings suggest that ocular areas and optic pathways, mainly optic chiasma, are important targets in the relapsing EAE. J. Neurosci. Res. 63:525–535, 2001. © 2001 Wiley‐Liss, Inc.
Age‐ and concentration‐dependent neuroprotection and toxicity by TNF in cortical neurons from β‐amyloid
Authors: Viel J.J. , McManus D.Q. , Smith Sherry S. , Brewer G.J.
Published: August 2002

The induction of an inflammatory response and release of cytokines such as TNF may be involved in the age‐related etiology of Alzheimer disease (AD). In the brain, microglia have been shown to produce a wide variety of immune mediators, including the pro‐inflammatory cytokine tumor necrosis factor (TNF). We hypothesize that with age there is increased ability of microglia to produce TNF or that age decreases the neuroprotective effect of TNF against beta‐amyloid (Aβ) toxicity in neurons. We investigated the effects of Aβ(1–40) on TNF secretion from forebrain cultures of microglia from embryonic, middle‐age (9‐month) and old (36‐month) rats. Over the first 12 hr of exposure to 10 μM Aβ (1–40), microglia from embryonic and old rats increase TNF secretion, although microglia from middle‐age rats did not produce detectable levels of TNF. When low concentrations of TNF are added to neurons together with Aβ (1–40) in the absence of exogenous antioxidants, neuroprotection for old neurons is significantly less than neuroprotection for middle‐age neurons. In neurons from old rats, high levels of TNF together with Aβ are more toxic than in neurons from middle‐age or embryonic rats. These results are discussed in relation to neuroprotection and toxicity of the age‐related pathology of AD. J. Neurosci. Res. 64:454–465, 2001. © 2001 Wiley‐Liss, Inc.