bluuebunny/crossref_metadata_2025 huggingface dataset:
Long‐term clinical and virological outcomes of chronic hepatitis C after successful interferon therapy
Authors: Tsuda Natsuko , Yuki Nobukazu , Mochizuki Kiyoshi , Nagaoka Takayuki , Yamashiro Masatoshi , Omura Masao , Hikiji Kazumasa , Kato Michio
Published: September 2004

Clinical relevance of occult hepatitis C virus (HCV) and/or hepatitis B virus (HBV) infection(s) remains uncertain years after interferon (IFN) therapy for chronic hepatitis C. By 1993, 38 sustained virological responders (SVRs) showing HCV RNA clearance at 6 months post‐treatment and 37 biochemical responders (BRs) with end‐of‐treatment alanine aminotransferase (ALT) normalization and subsequent 6‐month stabilization within 2 × the upper limit of normal (ULN) were enrolled. They were monitored for 4.4–12 years (median 6.8), then 15 SVRs and 15 BRs underwent paired liver biopsies. Biopsy samples were tested for positive and negative HCV RNA strands, and HBV DNA surface and X sequences. All SVRs showed sustained serum HCV RNA clearance during follow‐up, but hepatocellular carcinoma (HCC) developed in 4 (11%) SVRs. On paired liver biopsies, histological improvement was significant, but mild inflammation persisted in 87% of SVRs. Nonetheless, no HCV RNA sequence was amplified from liver tissues, and HBV DNA sequences were found in only one SVR. As for BRs, biochemical flare‐up of >2 × ULN occurred at a 5‐year risk of 41% (95% CI 24.7–56.4). The event was unpredictable but controllable by retreatment in 70%. Liver tissues after follow‐up contained positive and negative HCV RNA strands, but no HBV DNA sequence was amplified. These results suggest that SVRs, albeit free of occult HCV and/or HBV infection(s) over a decade, retain mild liver inflammation and the risk of HCC. Occult HBV was also shown uninvolved in flare‐up during follow‐up of BRs. J. Med. Virol. 74:406–413, 2004. © 2004 Wiley‐Liss, Inc.
Assessment of human cytomegalovirus specific T cell immunity in human immunodeficiency virus infected patients in different disease stages following HAART and in long‐term non‐progressors
Authors: Tamarit Amparo , Alberola Juan , Mira Josep Vicent , Tornero Carlos , Galindo María José , Navarro David
Published: September 2004

T cell immunity to human cytomegalovirus (HCMV) was assessed in HAART‐treated HIV‐1 infected patients (9 asymptomatic, CDC group A; and 22 symptomatic, CDC group B), and in eight HIV‐1 long term non‐progressors. Patients were either prospectively or cross‐sectionally examined for CD4+ T cell counts, HIV RNA load, HCMV leukoDNAemia, HCMV DNA in urine, lymphoproliferative response (LPR) to HCMV and phytohemagglutinin (PHA), and cytokine secretion (IFN‐γ and IL‐4) by HCMV‐stimulated peripheral blood mononuclear cell (PBMC) cultures. No patient either progressed to clinical AIDS or developed HCMV active infection during the study period. Twenty‐nine patients responded to HAART, though 12 patients failed to recover the LPR to HCMV over the study period (three from CDC group A and nine from CDC group B). In contrast to healthy control individuals, most patients displaying positive LPRs LPRs to HCMV had unstable responses. Sustained LPRs to HCMV were significantly associated with high pre‐HAART nadir CD4+ T cell counts. Long‐term suppression of HIV viremia correlated with recovery of LPR to HCMV. Sequential PBMC cultures from most patients secreted IFN‐γ (but not IL‐4) at normal levels upon HCMV stimulation, irrespective of the pre‐HAART nadir CD4+ T cell counts and CDC group to which patients belonged. Failure to reconstitute IFN‐γ response was associated with very low pre‐HAART nadir CD4+ T cell counts. Control of HCMV infection in the cohort was associated with either recovery or maintenance of IFN‐γ response rather than with reconstitution of LPR to HCMV. A LPR to HCMV was absent in three out of eight long term non‐progressors; contrarily, all patients showed preserved IFN‐γ responses. J. Med. Virol. 74:382–389, 2004. © 2004 Wiley‐Liss, Inc.
Seroepidemiology of hepatitis E virus infection among preschool children in Taiwan
Authors: Lin Ding‐Bang , Lin Jye‐Bin , Chen Shiuan‐Chih , Yang Chi‐Chiang , Chen Wen‐Kang , Chen Chien‐Jen
Published: September 2004

In order to study the seroprevalence of hepatitis E virus (HEV) infection among preschool children in Taiwan, a community‐based survey was carried out in 54 kindergartens in 10 urban areas, 10 rural areas, and 2 aboriginal areas randomly selected through stratified sampling. Serum specimens of 2,538 preschool children were screened for HEV antibodies (anti‐HEV) by a commercially available enzyme immunoassay. The odd ratios (OR) with 95% confidence intervals (CI) were estimated through multiple logistic regression analysis. A total of 86 children were anti‐HEV seropositive, giving a prevalence of 3.4%. The prevalence of anti‐HEV was 3.9% (19 of 484) among aboriginal children, a significantly increased seroprevalence compared with that among children who lived in urban areas (OR = 1.68; 95% CI = 1.56–2.95; P < 0.05). Females had a higher anti‐HEV seroprevalence than the males (OR = 1.55; 95% CI = 1.14–2.54; P < 0.05). Rates of anti‐HEV antibody increased with age in aboriginal areas (χ2 for trend = 5.59, P = 0.02), but decreased with age in non‐aboriginal areas. The poor water supply system, poor sewage disposal, exposure to wild animals, and other environmental conditions in the aboriginal areas might have played a role in their infection with HEV in Taiwan. J. Med. Virol. 74:414–418, 2004. © 2004 Wiley‐Liss, Inc.
Use of two real‐time polymerase chain reactions (PCRs) to detect herpes simplex type 1 and 2‐DNA after automated extraction of nucleic acid
Authors: Mengelle C. , Sandres‐Sauné K. , Miédougé M. , Mansuy J.‐M. , Bouquies C. , Izopet J.
Published: September 2004

Herpes simplex virus infections may be diagnosed by several techniques, including conventional cell culture and the polymerase chain reaction (PCR). This prospective study compares the analytical performances and usefulness of an in‐house real‐time PCR method and the Light Cycler HSV ½ detection kit™ (Roche Diagnostics, Mannheim, Germany). The results of both PCRs were then compared to those obtained by conventional cell culture. A total of 313 samples were tested (70 dermal samples, 81 cerebrospinal fluids (CSF), 47 ocular, 42 anogenital, 34 throat swabs, and 33 oral samples, 3 whole blood, 2 biopsies, and 1 bronchoalveolar lavage). Samples for molecular assays were extracted twice with the MagNa Pure instrument™ (Roche Molecular Biochemicals, Mannheim, Germany) and tested blind in parallel by the two PCR methods. Most (226) samples were also examined by cell culture. Forty three samples were found positive by both PCRs, whereas 267 were negative. The HSV‐1 and ‐2 typing of positive samples was identical. Three of the samples were positive in the in‐house PCR and negative in the Light Cycler HSV ½ detection kit. There was no statistically significant difference between the two tests. Only one sample gave an invalid result due to negative PCR and negative internal control result. Seven samples were positive by both real‐time PCRs and negative in conventional culture. The PCRs were significantly (P < 0.05) more sensitive. The results show good agreement between the two real‐time PCR methods, with the molecular tests being more sensitive than cell culture. J. Med. Virol. 74:459–462, 2004. © 2004 Wiley‐Liss, Inc.
Atypical clinical features of a human herpesvirus‐6 infection in a neonate
Authors: Yoshikawa Tetsushi , Suzuki Kenji , Umemura Kayoko , Akimoto Shiho , Miyake Fumi , Usui Chie , Fujita Ayano , Suga Sadao , Asano Yoshizo
Published: September 2004

A case of neonatal human herpesvirus 6 (HHV‐6) B infection is presented. Although HHV‐6 B was isolated from peripheral blood at the onset of the illness, a significant increase in viral antibody titers was not observed. The patient had a slight fever with generalized maculopapular skin rash and an increased number of atypical lymphocytes, which is quite different from the typical clinical features of exanthem subitum. J. Med. Virol. 74:463–466, 2004. © 2004 Wiley‐Liss, Inc.
Different chemokine expression in lethal and non‐lethal murine west nile virus infection
Authors: Shirato Kazuya , Kimura Takashi , Mizutani Tetsuya , Kariwa Hiroaki , Takashima Ikuo
Published: September 2004

West Nile (WN) virus is a mosquito‐borne flavivirus that can cause lethal encephalitis in humans and horses. The WN virus endemic in New York City (NY) in 1999 caused large‐scale mortality of wild birds that was not evident in endemic areas in other parts of the world, and the pathogenesis of the WN virus strain isolated in NY (NY strain) appears to differ from that of previously isolated strains. However, the pathogenesis of NY strain infection remains unclear. This study examined CC (RANTES/CCL5, MIP‐1α/CCL3, MIP‐1β/CCL4) and CXC (IP‐10/CXCL10, B lymphocyte chemoattractant (BLC/CXCL13), and B cell‐ and monocyte‐activating chemokine (BMAC/CXCL14)) chemokine expression during lethal NY strain and non‐lethal Eg101 strain infection in mice. We found that the mRNA of the CC chemokines, RANTES, MIP‐1α, MIP‐1β, and IP‐10 was highly up‐regulated in the brain of NY strain‐infected mice. By contrast, BLC mRNA was not detected in either group of mice, and BMAC mRNA was highly up‐regulated in late stage of infection with the non‐lethal Eg101 strain relative to levels in NY strain‐infected mice. J. Med. Virol. 74:507–513, 2004. © 2004 Wiley‐Liss, Inc.
Dispersion relation calculation of photonic crystals using the transmission line matrix method
Authors: Romo G. , Smy T.
Published: September 2004

In this paper we present the use of the transmission line matrix (TLM) method as a modelling tool for the computation of the dispersion relation of photonic crystals (PCs). First, the formulation of a complex‐valued TLM algorithm for the implementation of the periodicity condition on the sidewalls of the simulation domain (unit cell), is presented in detail. Then, the stability issues of this formulation are analysed from energy considerations. The analysis shows that the TLM method remains unconditionally stable since the equations enforcing the periodicity condition allow for the energy to be preserved as a constant during the simulations. Finally, the complex‐valued TLM algorithm is validated by simulating two PCs and by comparing the results with those predicted by alternative methods. Copyright © 2004 John Wiley & Sons, Ltd.
Role for calcium‐activated potassium channels (BK) in growth control of human malignant glioma cells
Authors: Weaver Amy K. , Liu Xiaojin , Sontheimer Harald
Published: September 2004

Voltage‐dependent large‐conductance Ca2+‐activated K+ channels, often referred to as BK channels, are a unique class of ion channels coupling intracellular chemical signaling to electrical signaling. BK channel expression has been shown to be up‐regulated in human glioma biopsies, and expression levels correlate positively with the malignancy grade of the tumor. Glioma BK channels (gBK) are a splice variant of the hslo gene, are characterized by enhanced sensitivity to [Ca2+]i, and are the target of modulation by growth factors. By using the selective pharmacological BK channel inhibitor iberiotoxin, we examined the potential role of these channels in tumor growth. Cell survival assays examined the ability of glioma cells to grow in nominally serum‐free medium. Under such conditions, BK channel inhibition by iberiotoxin caused a dose‐ and time‐dependent decrease in cell number discernible as early as 72 hr after exposure and maximal growth inhibition after 4–5 days. FACS analysis shows that IbTX treatment arrests glioma cells in S phase of the cell cycle, whereupon cells undergo cell death. Interestingly, IbTX effects were nullified when cells were maintained in 7% fetal calf serum. Electrophysiological analysis, in conjunction with biotinylation studies, demonstrates that serum starvation caused a significant translocation of BK channel protein to the plasma membrane, corresponding to a two‐ to threefold increase in whole‐cell conductance, but without a change in total gBK protein. Hence, expression of functional gBK channels appears to be regulated in a growth‐factor‐dependent manner, with enhanced surface expression promoting tumor cell growth under conditions of growth factor deprivation as might occur under in vivo conditions. © 2004 Wiley‐Liss, Inc.
Role of catecholaminergic inputs to the medial prefrontal cortex in local and subcortical expression of Fos after psychological stress
Authors: Spencer Sarah J. , Day Trevor A.
Published: September 2004

A wide variety of stressors elicit Fos expression in the medial prefrontal cortex (mPFC). No direct attempts, however, have been made to determine the role of the inputs that drive this response. We examined the effects of lesions of mPFC catecholamine terminals on local expression of Fos after exposure to air puff, a stimulus that in the rat acts as an acute psychological stressor. We also examined the effects of these lesions on Fos expression in a variety of subcortical neuronal populations implicated in the control of adrenocortical activation, one classic hallmark of the stress response. Lesions of the mPFC that were restricted to dopaminergic terminals significantly reduced numbers of Fos‐immunoreactive (Fos‐IR) cells seen in the mPFC after air puff, but had no significant effect on stress‐induced Fos expression in the subcortical structures examined. Lesions of the mPFC that affected both dopaminergic and noradrenergic terminals also reduced numbers of Fos‐IR cells observed in the mPFC after air puff. Additionally, these lesions resulted in a significant reduction in stress‐induced Fos‐IR in the ventral bed nucleus of the stria terminalis. These results demonstrate a role for catecholaminergic inputs to the mPFC, in the generation of both local and subcortical responses to psychological stress. © 2004 Wiley‐Liss, Inc.
Modulation of AMPA receptors in spinal motor neurons by the neuroprotective agent riluzole
Authors: Albo Federica , Pieri Massimo , Zona Cristina
Published: September 2004

We investigated the interaction of riluzole, a therapeutic agent used in amyotrophic lateral sclerosis (ALS), with α‐amino‐3‐hydroxy‐5‐methyl‐4‐isoxazole propionic acid (AMPA) receptor channels in mouse spinal motor neurons in culture using whole‐cell patch‐clamp recording techniques. Kainate elicited concentration‐dependent (EC50 = 35 μM) inward currents in all the patched cells. These responses were mediated primarily through the activation of AMPA receptors with a negligible contribution from kainate receptors, because bath application of 100 μM GYKI53655, a potent noncompetitive AMPA receptor antagonist, completely blocked the kainate‐induced currents. Riluzole (0.5–100 μM) reduced in a dose‐dependent manner the kainate‐induced currents with an IC50 of 1.54 μM in all tested neurons (n = 25) and this effect was found to be reversible. The response to kainate decreased in the presence of 1 μM riluzole in all spinal motor neurons tested, without changing its EC50, indicating a noncompetitive mechanism of inhibition. The amplitude of the responses induced by kainate under control condition and during riluzole was a linear function of the membrane potential. The reversal potential of the current was not significantly different in the two experimental conditions, whereas the total conductance of the motor neurons for the currents induced by 100 μM kainate was reduced significantly in the presence of 1 μM riluzole (P < 0.05). These results reveal an interaction of riluzole with glutamatergic neurotransmission in spinal cord motor neurons and can contribute to explain its beneficial effect in the ALS treatment. © 2004 Wiley‐Liss, Inc.
α lipoic acid inhibits human T‐cell migration: Implications for multiple sclerosis
Authors: Marracci Gail H. , McKeon Gabriel P. , Marquardt Whitney E. , Winter Rolf W. , Riscoe Michael K. , Bourdette Dennis N.
Published: September 2004

We have demonstrated previously the ability of the antioxidant α lipoic acid (ALA) to suppress and treat a model of multiple sclerosis (MS), relapsing experimental autoimmune encephalomyelitis (EAE). We describe the effects of ALA and its reduced form, dihydrolipoic acid (DHLA), on the transmigration of human Jurkat T cells across a fibronectin barrier in a transwell system. ALA and DHLA inhibited migration of Jurkat cells in a dose‐dependent fashion by 16–75%. ALA and DHLA reduced matrix metalloproteinase‐9 (MMP‐9) activity by 18–90% in Jurkat cell supernatants. GM6001, a synthetic inhibitor of MMP, reduced Jurkat cell migration, but not as effectively as ALA and DHLA did. Both ALA and DHLA downmodulated the surface expression of the α4β1 integrin (very late activation‐4 antigen; VLA‐4), which binds fibronectin and its endothelial cell ligand vascular cell adhesion molecule‐1 (VCAM‐1). Moreover, ALA, but not DHLA, reduced MMP‐9‐specific mRNA and extracellular MMP‐9 from Jurkat cells and their culture supernatants as detected by relative reverse transcriptase‐polymerase chain reaction (RT‐PCR) and enzyme‐linked immunosorbent assay (ELISA), respectively. ALA and DHLA inhibited Jurkat cell migration and have different mechanisms for inhibiting MMP‐9 activity. These data, coupled with its ability to treat relapsing EAE, suggest that ALA warrants investigation as a therapy for MS. © 2004 Wiley‐Liss, Inc.
Hepatocyte growth factor improved learning and memory dysfunction of microsphere‐embolized rats
Authors: Date Ichiro , Takagi Norio , Takagi Keiko , Kago Tomoyuki , Matsumoto Kunio , Nakamura Toshikazu , Takeo Satoshi
Published: September 2004

Hepatocyte growth factor (HGF), an organotropic factor for regeneration and protection in various organs, has the ability to attenuate cerebral ischemia‐induced cell death. The effect of HGF on learning and memory function after cerebral ischemia, however, remains unknown. We have demonstrated that administration of human recombinant HGF (hrHGF) into the ventricle reduced prolongation of the escape latency in acquisition and retention tests of the water maze task on Days 12–28 after microsphere embolism‐induced cerebral ischemia. Treatment with hrHGF also attenuated the decrease in viable area and the density and number of perfused cerebral vessels, particularly those with a diameter smaller than 10 μm, of the ipsilateral hemisphere on Day 28 after the cerebral ischemia. We observed that treatment with hrHGF reduced the number of TUNEL‐positive cerebral endothelial cells at the early stage after the ischemia. These results suggest that hrHGF prevents learning and memory dysfunction seen after sustained cerebral ischemia by protecting against injury to the endothelial cells. HGF treatment may be a potent therapeutic strategy for cerebrovascular diseases, including cerebral infarct and vascular dementia. © 2004 Wiley‐Liss, Inc.
Antioxidants are required during the early critical period, but not later, for neuronal survival
Authors: Perry Seth W. , Norman John P. , Litzburg Angela , Gelbard Harris A.
Published: September 2004

Methods for growing primary neuronal cultures rely on the inclusion of antioxidants in the culture medium, but no studies have determined precisely if or when antioxidants are required for neuronal survival, despite the significance this information would have for understanding neurodevelopment and studying oxidative stress. We show that cortical neurons grown in Neurobasal media with B27 supplement required antioxidants for only the first 24 hr post‐explantation, after which the antioxidants could be removed permanently without noticeable loss of neuronal survival over the normal lifespan. Cortical cultures never exposed to antioxidants did not survive. These findings represent a novel method for substantially antioxidant‐free neuronal culture, whereby antioxidants can be removed permanently from the cultures after only 1 day. This method may prove critical for studies of oxidative stress, because B27 antioxidants significantly diminished pro‐oxidative effects of the excitatory neurotransmitter glutamate and hydrogen peroxide on cortical cultures, even if antioxidants were removed before the oxidizing treatment. Together, these findings suggest a brief window of high vulnerability to reactive oxygen species, and have important implications for studies of oxidative stress and developmental neuroscience. © 2004 Wiley‐Liss, Inc.
FT‐Raman and FT‐IR spectroscopic study of synthetic Mg/Zn/Al‐hydrotalcites
Authors: Kloprogge J. Theo , Hickey Leisel , Frost Ray L.
Published: September 2004

Synthetic Mg/Zn/Al‐hydrotalcites with atomic ratios of 6:0:2, 4:2:2, 2:4:2 and 0:6:2 were characterized by FT‐Raman and FT‐IR spectroscopy. ‘AlOH’ IR translation modes are observed at 419, 427, 559, 616 and 771 cm−1 with two corresponding Raman bands at 465–477 and 547–553 cm−1. ‘MgOH’ IR translation modes are found at 412, 559 and 616 cm−1 with equivalent Raman bands at 464–477 and 547–553 cm−1. The ‘ZnOH’ IR translation mode is found at 445 cm−1 and the Raman modes around 450 and 495 cm−1. The CO32 − group is identified by the ν1(IR) at 1112 cm−1 and a doublet in the Raman around 1045–1055 and 1060 cm−1. ν2(IR) is observed at 874 cm−1. ν3(IR) is a doublet at 1359 and 1381 cm−1. ν4 is observed in both the IR and Raman spectra around 670 and 695–715 cm−1, respectively. In the OH deformation region, a doublet is observed for ‘AlOH’ at 955 and 1033 cm−1 in the IR spectra. The ‘ZnOH’ IR deformation mode is observed at 1462 cm−1. H2O is characterized by a bending mode at 1632 cm−1 and an H‐bonded interlayer H2O mode at 3266 cm−1 with a Raman band between 3244 and 3271 cm−1. The OH stretching region is characterized by three bands in the Raman spectra around 3355–3360, 3440–3455 and 3535–3580 cm−1. One band is observed in the IR spectra at 3471 cm−1. Copyright © 2004 John Wiley & Sons, Ltd.
Effect of solution concentration on the Raman scattering cross‐section of carbon tetrachloride
Authors: Yin Jian‐Hua , Gao Shu‐Qin , Li Zuo‐Wei , Yu Ying‐Ning , Lu Guo‐Hui , Tian Yan‐Jie
Published: September 2004

Using the liquid‐core optical fiber technique, we measured the Raman spectral intensities of CCl4 in CS2 at concentrations ranging from 90 to 0.05% (v/v). Raman scattering cross‐sections (RSCSs) of the 459, 314 and 218 cm−1 CCl4 bands were calculated using Onsager's theory with the 656 cm−1 Raman band of CS2 as an internal standard. The results show that the RSCSs of the three CCl4 bands increase with decreasing concentration of CCl4 over the whole range measured. It was unexpected that the RSCSs show different changes in various ranges, that is, a flat linear change at higher concentrations and a strong change at lower concentrations. With decrease in CCl4 concentration from 90 to 0.05% (0.1% for the 314 cm−1 band), the RSCSs of the 459 and 314 cm−1 bands show large increases. The RSCS of the 218 cm−1 band shows a relatively small change in the measured range. Copyright © 2004 John Wiley & Sons, Ltd.
Characterisation of phenolic extracts from olive pulp and olive pomace by electrospray mass spectrometry
Authors: Cardoso Susana M , Guyot Sylvain , Marnet Nathalie , Lopes‐da‐Silva José A , Renard Catherine MGC , Coimbra Manuel A
Published: September 2004

Methanol extracts of olive pomace (two‐phase olive oil extraction) and olive pulp were analysed by reverse phase HPLC and the eluted fractions were characterised by electrospray ionisation mass spectrometry. This technique allowed the identification of some common phenolic compounds, namely, verbascoside, rutin, caffeoyl‐quinic acid, luteolin‐4‐glucoside and 11‐methyl‐oleoside. Hydroxytyrosol‐1′‐β‐glucoside, luteolin‐7‐rutinoside and oleoside were also detected. Moreover, this technique enabled the identification, for the first time in Olea europaea tissues, of two oleoside derivatives, 6′‐β‐glucopyranosyl‐oleoside and 6′‐β‐rhamnopyranosyl‐oleoside, and of 10‐hydroxy‐oleuropein. Also, an oleuropein glucoside that had previously been identified in olive leaves was now detected in olive fruit, both in olive pulp and olive pomace. With the exception of oleoside and oleuropein, the majority of phenolic compounds were found to occur in equivalent amounts in olive pulp and olive pomace. Oleoside was the main phenolic compound in olive pulp (31.6 mg g−1) but was reduced to 3.6 mg g−1 in olive pomace, and oleuropein (2.7 mg g−1 in the pulp) almost disappeared (<0.1 mg g−1 in the pomace). Both these phenolic compounds were degraded during the olive oil extraction process. Copyright © 2004 Society of Chemical Industry
Heat‐induced denaturation impairs digestibility of legume (Phaseolus vulgaris L and Vicia faba L) 7S and 11S globulins in the small intestine of rat
Authors: Carbonaro M , Grant G , Cappelloni M
Published: September 2004

7S globulin from common bean (Phaseolus vulgaris L) and 11S globulin from faba bean (Vicia faba L) were isolated to over 90% purity and the digestibility of the proteins, either in native or denatured (120 °C, 20 min, 1 atm) state, was tested in the small intestine of growing rats in acute (1 h) experiments. Native globulins were well digested (92 and 95% for 7S and 11S proteins, respectively). However, after thermal denaturation, protein digestibility of 7S globulin was reduced to 88%, while that of 11S globulin to only 79%. SDS‐PAGE revealed that high amounts of the intermediate proteolytic products of phaseolin (MW 22 000–27 000 Da) were present in the small intestine of rats after 1 h digestion of the denatured 7S globulin, while protein material in the high MW range (>55 000 Da) were recovered from the 11S globulin. The overall negative charge of unavailable proteins from the 7S globulin was found by anion exchange–FPLC separation to be higher than that of products from the 11S globulin. MALDI‐MS analysis of proteins in the small intestine confirmed the presence of half‐size phaseolin subunits (MW 23 700 Da) as breakdown products from the denatured 7S globulin, and of highly hydrophobic basic subunits (MW 20 000 Da) from the 11S globulin. Copyright © 2004 Society of Chemical Industry
Micellar electrokinetic chromatography with laser‐induced fluorescence detection for sensitive determination of ephedrine and pseudoephedrine
Authors: Xie Jianping , Zhang Jiyou , Liu Jiaqin , Tian Jianniao , Chen Xingguo , Hu Zhide
Published: September 2004

A selective and sensitive micellar electrokinetic chromatography method with laser‐induced fluorescence detection was developed for the quantification of ephedrine (E) and pseudoephedrine (PE) derivatized with 4‐chloro‐7‐nitrobenzo‐2‐oxa‐1,3‐diazole. After conducting a series of optimizations, a running buffer of 10 mM sodium borate + 16 mM SDS was used for separation of the derivatives. A linear relationship for E and PE was obtained in the range of 0.044–6.6 μg mL–1 (correlation coefficient: 0.9943 for E, 0.9946 for PE), and the detection limits for E and PE were 0.70 and 0.30 ng mL–1, respectively. The sensitivity of E and PE was improved by several multiples of ten over those of CZE‐LIF method. The method was applied to the analysis of the two alkaloids in ephedra herbal medicine and preparations with recoveries in the range of 98.3–107.1%.
Micellar electrokinetic chromatography with laser‐induced fluorescence detection for rapid and sensitive analysis of two new bioactive reagents using dynamic covalent coating
Authors: Xie Jian Ping , Cui Feng Ling , Chen Xing Guo , Hu Zhi De
Published: September 2004

A simple, rapid, selective, and sensitive micellar electrokinetic chromatography (MEKC) with laser‐induced fluorescence detection (LIF) method was developed, using hexamethyldisilazane (HMDS) as dynamic covalent coating (DCC), for the analysis of two new bioactive agents N‐n‐hexyl‐N ´‐(sodium p‐aminobenzenesulfonate) thiourea (HXPT) and N‐n‐undecyl‐N ´‐(sodium p‐aminobenzenesulfonate) thiourea (UPT) derivatized with 4‐chloro‐7‐nitrobenzo‐2‐oxa‐1,3‐diazole. MEKC methods both not using DCC and using DCC were investigated. In a series of optimization steps, DCC and a running buffer of 20 mM Na2B4O7 + 16 mM SDS + 8% acetonitrile were applied for determination of the derivatives. Linear relationships for HXPT and UPT were obtained in the range of 5 to 100 μM (correlation coefficient: 0.9986 for HXPT, 0.9978 for UPT), and the detection limits for HXPT and UPT were 16.5 and 39.0 ng mL–1. The sensitivity was improved over that of fluorescence spectroscopy methods. The method was applied to the analysis of the two reagents in lab water waste with recoveries in the range of 95.6–107.5%.
Fast GC analysis with a 50 μm ID column: theory, practical aspects, and application to a highly complex sample
Authors: Mondello Luigi , Tranchida Peter Quinto , Casilli Alessandro , Favoino Olinda , Dugo Paola , Dugo Giovanni
Published: September 2004

This research focuses on the minimization of GC analysis times through the use of a 5 m×0.05 mm ID×0.05 μm (film thickness) column. Experimental minimum plate height (Hmin) and optimum linear velocity values were derived from standard compound applications, under various analytical conditions, and then related to classical chromatographic theory. Deviations from the latter are measured and discussed. Practical aspects linked to the use of such capillaries, such as column sample capacity and detector acquisition rates, are also considered. Furthermore, a fast, and what can be considered a very fast method, were applied to the separation of a fuel sample. Coefficients of variation of elution times and relative peak areas were calculated in the very fast application. All analytical results are compared with those obtained by conventional 0.25 mm ID column applications.
Large volume splitless injection with concurrent solvent recondensation: Keeping the sample in place in the hot vaporizing chamber
Authors: Biedermann Maurus , Fiscalini Alessandro , Grob Koni
Published: September 2004

An injector liner packed with a plug of glass wool is compared with a laminar and a mini laminar liner for large volume (20–50 μL) splitless injection with concurrent solvent recondensation (CSR‐LV splitless injection). Videos from experiments with perylene solutions injected into imitation injectors show that glass wool perfectly arrested the sample liquid and kept it in place until the solvent had evaporated. The sample must be transferred from the needle to the glass wool as a band, avoiding ‘thermospraying’ by partial solvent evaporation inside the needle. The liquid contacted the liner wall when the band was directed towards it, but from there it was largely diverted to the glass wool. In the laminar liners, part of the liquid remained and evaporated at the entrance of the obstacle, while the other proceeded to the center cavity. Vapors formed in the center cavity drove liquid from the entrance of the obstacle upwards, but the importance of such problems could not be verified in the real injector. Some liquid split into small droplets broke through the obstacle and entered the column. Breakthrough through the laminar liners was confirmed by a chromatographic experiment. An improved design of a laminar liner for large volume injection is discussed as a promising alternative if glass wool causes problems originating from insufficient inertness.
Second-harmonic near-field optical microscopy of periodic
nanoholes in metal films
Authors: Beermann J , Bozhevolnyi S I
Published: September 2004

Using a second-harmonic (SH) scanning near-field
optical microscope (SNOM) working in transmission with an uncoated
fiber tip, we obtain highly detailed fundamental harmonic (FH) and
SH images of a ∼50-nm-thick gold film deposited on a glass
substrate and containing a ∼830-nm-period array of slightly
elongated holes (diameters in perpendicular directions are
∼170 and 260 nm). The FH and SH images for three excitation
wavelengths (730, 800, and 870 nm) are presented for different
polarization combinations of the FH-incident and FH- and
SH-detected radiations. It is seen that the symmetry of the FH
images is primarily determined by the symmetry of surface plasmon
polaritons (SPPs) excited (at the FH wavelength) at the gold-air
interface, whereas the symmetry of the SH images is mainly
governed by the symmetry of holes. We notice large differences in
the strength of SH signals originating at different (nominally
identical) holes and relate this feature to interference in the
developed multiple scattering of SPPs.
Coherence and correlation in semiconductor microcavities
Authors: Di Stefano O , Savasta S , Girlanda R
Published: September 2004

We present an overview of our results concerning the
influence of two-pair continuum coherences on the transient
nonlinear optical response of semiconductor microcavities. We show
that the interplay between these 4-particle coherences and the
nonperturbative light-matter interaction produces highly desirable
almost decoherence-free exciton-exciton collisions on the lower
polariton branch. This effect gives rise to the very different
nonlinear absorption rates on the two polariton branches observed
in many experiments and make possible to reach a very high degree
of amplification in samples with large Rabi splitting. Moreover,
we show that the availability of almost decoherence free
exciton-exciton collisions can be used for the realization of
coherent trapping of polariton emission and amplification. This
coherent manipulation and trapping of many-particle polariton
states can be performed employing both ultrafast and continuous
wave operation.
A symmetry based approach to evaluation of carbon nanotube
electronic hyperpolarizability
Authors: De Dominicis L , Fantoni R , Botti S , Asilyan L
Published: September 2004

The properties of the carbon nanotubes (CNTs)
hyperpolarizability β due to π electrons is studied by
using the formalism of the irreducible representations of CNT
space symmetry group (G). The main contribution to the
second order nonlinearity is demonstrated to come from electrons
at the origin of the Brillouin zone (k=0). Within this scheme, a
description based on the isogonal point group associated to
G accounts for the relevant properties of β.
Der Einfluss von Oxidationsmitteln auf die Korrosionsbeständigkeit von Nicrofer 3127 hMo in niedrig‐ und mittelkonzentrierter Schwefelsäure
Authors: Werner H. , Klöwer J. , Alves H.
Published: September 2004

Für Nicrofer 3127 hMo wurden aus 24 h‐Versuchen mit gravimetrischer Auswertung die Isokorrosionslinien für eine Abtragungsgeschwindigkeit < 0,1 mm/a in belüfteter technischer und p.a. Schwefelsäure jeweils ohne und mit 1 g/l Chlorid im Konzentrationsbereich bis 90% ermittelt. Messungen des Freien Korrosionspotentials belegen, dass die höhere Beständigkeit von Nicrofer 3127 hMo in der technischen Säure auf deren Oxidationsmittelgehalt zurückzuführen ist.

Dieser wirkt ab einer Schwefelsäurekonzentration von 20% passivitätserhaltend bei Temperaturen, die in Abhängigkeit von der Säurekonzentration 10–50 K über der Isokorrosionslinie von p.a. Schwefelsäure liegen. Bei Schwefelsäurekonzentrationen bis 10% ist der Oxidationsmittelgehalt der technischen Schwefelsäure zu gering, um die Korrosionsbeständigkeit von Nicrofer 3127 hMo gegenüber der in p.a. Säure zu verbessern.

In den chloridhaltigen Schwefelsäuren verhält sich Nicrofer 3127 hMo analog. Infolge der aktivierenden Wirkung des Chlorides wird der Einsatzbereich im Vergleich zu den chloridfreien Schwefelsäuren durch niedrigere Temperaturen begrenzt.
Protective organic‐inorganic hybrid coatings on mild steel derived from Ti(OC4H9)4‐modified precursors
Authors: Nguyen V. , Perrin F. X. , Vernet J. L.
Published: September 2004

Titania‐poly(methyl methacrylate‐co‐butyl methacrylate‐co‐methacrylic acid) hybrids prepared by a sol‐gel method were deposited by dip coating on mild steel. Transparent and defect free coatings with titania content ranging between 0 and 12.7 wt.% have been prepared. Barrier properties and dry adherence have been tested by electrochemical impedance spectroscopy (EIS) and the vertical pull‐off test, respectively. The pull‐off test results suggest that the titanium alkoxide precursor must intercede on the substrate/coating interphase during film formation to create specific adhesive bondings with the substrate.

In this paper, two capacitance models are used to estimate the water uptake, one based on a uniform and one on a heterogeneous distribution of sorbed water. Water uptake determined from these two models is compared to the gravimetry results. It is suggested that a reliable determination of the actual water uptake in coatings from capacitance measurements require an extensive experimental work. The variations in the state of sorbed water with the specimen type or immersion time, the leaching of organics during immersion or the slow diffusion of ions are fundamental factors that must be considered when comparing the water uptake determined from gravimetry and capacitance models.
Effect of Thermal Degradation on Glass Transition Temperature of PMMA
Authors: Wondraczek Katrin , Adams Jörg , Fuhrmann Jürgen
Published: September 2004

Summary: For industrial polymer applications, the structure‐property relation during thermal treatment is of high interest. If a polymer is degraded, its molecular structure will alter, and its mechanical properties are affected as well; thus limiting the usability. The objective of this paper is to highlight the effect of thermal degradation on the glass transition temperature of the remaining polymer. We used commercial atactic poly(methyl methacrylate) (PMMA) as an example. The residue of an oxidatively degraded PMMA was analyzed in terms of its structure‐property relation. A characteristic evolution of the glass transition temperature as a function of degradation time was observed. The glass transition temperature of the degradation product correlates with the molecular weight, monomer content, and tacticity of the remaining polymer. Based on the Tg data, four different degradation domains are discussed in detail. Each period is characterized by a certain trend in Tg due to specialities of the superimposing rate processes.

Glass transition temperature versus normalized weight loss as determined by DDSC measurements.

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Glass transition temperature versus normalized weight loss as determined by DDSC measurements.
Preparation of Polymeric Nanoparticles by Photo‐Crosslinking of an Acryloylated Polyaspartamide in w/o Microemulsion
Authors: Craparo Emanuela Fabiola , Cavallaro Gennara , Bondì Maria Luisa , Giammona Gaetano
Published: September 2004

Summary: Biodegradable polymeric nanoparticles have been prepared by UV irradiation of an acryloylated water soluble polymer by an inverse microemulsion. The starting polymer was a α,β‐poly(N‐2‐hydroxyethyl)‐D,L‐aspartamide (PHEA) partially functionalized with glycidyl methacrylate (GMA) in order to introduce reactive vinyl groups in the side chain. The PHEA‐GMA copolymer obtained (PHG) was crosslinked by UV irradiation of the inverse microemulsion prepared by mixing an aqueous solution of PHG with propylene carbonate (PC)/ethyl acetate (EtOAc) in the presence of sorbitan trioleate (SPAN 85) as surfactant. Nanoparticles obtained were characterized by FTIR spectrophotometry, transmission electron microscopy, size distribution analysis and zeta potential measurements. Nanoparticles investigated revealed spherical and homogeneous shading, the particle size having a mean diameter of 88 ± 13 nm (PDI = 0.21) and a negative surface charge in several aqueous media. Moreover, in vitro chemical and enzymatic hydrolysis studies evidenced the partial biodegradability of PHG nanoparticles, which is more evident after incubation with enzymes such as esterases. PHG nanoparticles were loaded during UV irradiation process with Cytarabine, chosen as a model drug, and Cyt‐loaded PHG nanoparticles were able to release it in a simulated physiological fluid (phosphate buffer at pH 7.4) and in blood plasma.

Transmission electron micrograph of photo‐crosslinked PHG.

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Transmission electron micrograph of photo‐crosslinked PHG.
Synthesis of Laser‐Alignable Liquid Crystalline Conducting Polymers
Authors: Brown John W. , Foot Peter J. S. , Gabaston Laurence I. , Ibison Paul , Prevost Adeline
Published: September 2004

Summary: The synthetic routes to three series of liquid crystal conducting polymers (based on pyrrole, thiophene, and aniline monomers) are reported and the optimum conditions for polymer preparation are described. These polymers show increased conductivity when laser‐aligned, the greatest effect being shown by the N‐substituted pyrrole‐based system. Information on their liquid crystal and spectroscopic properties and other characteristics are also included.

Structure of the monomers M1, M2, and M3.

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Structure of the monomers M1, M2, and M3.
Polycarbonate/Montmorillonite Nanocomposites Prepared by Microwave‐Aided Solid State Polymerization
Authors: Yoo Youngjae , Choi Kil‐Yeong , Lee Jae Heung
Published: September 2004

Summary: Polycarbonate/montmorillonite (MMT) nanocomposites were prepared by microwave solid‐state polymerization. The MMTs were modified with alkyl ammonium salt. Pre‐intercalated polycarbonate nanocomposite was prepared using two conventional methods; a melt process and a solution process. Melt processing was accomplished in a Haake internal mixer for 30 mins at 180 °C. Solution processing was accomplished in a homogenizer using chloroform. The wide‐angle X‐ray diffraction (WAXD) peak indicating the gallery size of MMTs was shifted to lower levels after the pre‐intercalation process. Subsequently, microwave solid‐state polymerization converted the pre‐intercalated nanocomposite into the exfoliated nanocomposite. WAXD revealed that exfoliation and/or further intercalated structures were obtained when comparing the results from the microwave solid‐state polymerization with results from conventional solid‐state polymerization using oil heating. This means that microwave solid‐state polymerization is more effective than conventional solid‐state polymerization using oil heating. It was shown that conventional melt and solution processing of MMT and polycarbonate prepolymer yielded intercalated nanocomposites with interlayer spacing of 2.5 and 2.7 nm respectively. Microwave solid‐state polymerized nanocomposite showed the exfoliated and/or intercalated structure, whereas conventional solid‐state polymerization using oil heating only increased the gallery size of MMT. The thermal decomposition behavior and morphologies were investigated by thermogravimetric analysis (TGA) and transmission electron microscopy (TEM).

Schematic diagram of microwave solid‐state polymerization.

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Schematic diagram of microwave solid‐state polymerization.
The Kodaira dimension of certain moduli spaces of Abelian surfaces
Authors: Erdenberger C.
Published: September 2004

The moduli space of (1, p)‐polarized abelian surfaces is a quasi‐projective variety. In the case when p is a prime, we want to study its Kodaira dimension. We will show that it is of general type for p > 71 and some smaller values of p. This improves an earlier result of G. K. Sankaran. (© 2004 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Nonautonomous abstract Cauchy problems for strongly measurable families
Authors: Tanaka Naoki
Published: September 2004

This paper is devoted to the study of the inhomogeneous abstract Cauchy problem for time‐dependent linear evolution equation u′(t) = A(t)u(t) + f(t) for t ∈ [0, T], under the strong measurability of A and a new type of quasi‐stability condition from the viewpoint of the theory of finite difference approximations. (© 2004 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Synthesis of Polyaniline Nanobelts
Authors: Li Guicun , Peng Hongrui , Wang Yi , Qin Yong , Cui Zuolin , Zhang Zhikun
Published: September 2004

Summary: Polyaniline nanobelts have been synthesized by a self‐assembly process using the chemical oxidative polymerization of aniline in a surfactant gel. The morphologies of polyaniline nanostructures were characterized by field‐emission scanning electron microscopy and transmission electron microscopy. The effects of the concentrations of cetyltrimethylammonium bromide on the morphologies of polyaniline nanostructures have also been investigated.

A scanning electron microscopy image of polyaniline nanobelts synthesized with 0.12 M cetyltrimethylammonium bromide at −7 °C.

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A scanning electron microscopy image of polyaniline nanobelts synthesized with 0.12 M cetyltrimethylammonium bromide at −7 °C.
Preparation of Antimicrobial Ultrafine Cellulose Acetate Fibers with Silver Nanoparticles
Authors: Son Won Keun , Youk Ji Ho , Lee Taek Seung , Park Won Ho
Published: September 2004

Summary: A feasible method for the preparation of antimicrobial ultrafine fibers with silver nanoparticles was developed by direct electrospinning of a cellulose acetate (CA) solution with small amounts of silver nitrate followed by photoreduction. Silver nanoparticles in ultrafine CA fibers were stabilized by interactions with carbonyl oxygen atoms in CA. Ultrafine CA fibers with silver nanoparticles showed very strong antimicrobial activity.

TEM image of an ultrafine CA fiber electrospun from 10 wt.‐% CA solution with 0.5 wt.‐% AgNO3.

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TEM image of an ultrafine CA fiber electrospun from 10 wt.‐% CA solution with 0.5 wt.‐% AgNO3.
Crazing and Fracture in Polymers: Micro‐Mechanisms and Effect of Molecular Variables
Authors: Kausch H.H. , Halary J.‐L. , Plummer C.J.G.
Published: September 2004

The influence of the primary molecular parameters chain configuration, architecture and molecular weight (MW) on the mode of mechanical breakdown is discussed for two series of (amorphous) thermoplastic polymers, methyl methacrylate glutarimide copolymers and amorphous semi‐aromatic polyamides. Structural and dynamic analyses and fracture mechanical methods applied to such adequately chemically modified (glassy) polymers permit us to show and to explain the effect of intrinsic variables on local molecular motions and on the competition between chain scission, disentanglement and segmental slip, which in turn determine the dominant mode of instability and plastic behaviour. Above a critical molecular weight, toughness depends most strongly on the entanglement density; a positive effect of the intensity of sub‐Tg relaxations and in‐chain cooperative motions on the toughness of these materials is clearly evident.
Linear Viscoelasticity and Non‐Linear Elasticity of Block Copolymer Blends Used as Soft Adhesives
Authors: Roos Alexandra , Creton Costantino
Published: September 2004

The debonding of pressure‐sensitive‐adhesives from a rigid surface often occurs with the formation of a fibrillar structure bridging the surface and the adhesive. This fibrillar structure is responsible for the large (of the order of 1 kJ/m2) adhesion energy, which is measured, for this type of adhesive despite the very low level of applied stress. One way to account for this dissipated energy is viscous flow in the elongation process of the fibrils. However, for certain types of adhesives, the extension of the fibrils is essentially a quasi reversible elastic process and the energy is only dissipated rather rapidly when the fibrils are detached from the surface. It is therefore essential to characterize the elastic properties of theses adhesives not only in the linear viscoelastic regime but also in the large strain non‐linear elastic domain. We have therefore performed tensile tests of model adhesive films based on block copolymers. The respective roles played by the linear viscoelasticity and non‐linear elasticity in controlling the properties will be discussed.