bluuebunny/crossref_metadata_2025 huggingface dataset:
Fusing EEG and fMRI based on a bottom-up model: inferring activation and effective connectivity in neural masses
Authors: Riera J , Aubert E , Iwata K , Kawashima R , Wan X , Ozaki T
Published: June 2005

The elucidation of the complex machinery used by the human brain to segregate and integrate information while performing high cognitive functions is a subject of imminent future consequences. The most significant contributions to date in this field, known as cognitive neuroscience, have been achieved by using innovative neuroimaging techniques, such as electroencephalogram (EEG) and functional magnetic resonance imaging (fMRI), which measure variations in both the time and the space of some interpretable physical magnitudes. Extraordinary maps of cerebral activation involving function-restricted brain areas, as well as graphs of the functional connectivity between them, have been obtained from EEG and fMRI data by solving some spatio-temporal inverse problems, which constitutes a top-down approach. However, in many cases, a natural bridge between these maps/graphs and the causal physiological processes is lacking, leading to some misunderstandings in their interpretation. Recent advances in the comprehension of the underlying physiological mechanisms associated with different cerebral scales have provided researchers with an excellent scenario to develop sophisticated biophysical models that permit an integration of these neuroimage modalities, which must share a common aetiology. This paper proposes a bottom-up approach, involving physiological parameters in a specific mesoscopic dynamic equations system. Further observation equations encapsulating the relationship between the mesostates and the EEG/fMRI data are obtained on the basis of the physical foundations of these techniques. A methodology for the estimation of parameters from fused EEG/fMRI data is also presented. In this context, the concepts of activation and effective connectivity are carefully revised. This new approach permits us to examine and discuss some future prospects for the integration of multimodal neuroimages.
Tissue tropism of recombinant coxsackieviruses in an adult mouse model
Authors: Harvala Heli , Kalimo Hannu , Bergelson Jeffrey , Stanway Glyn , Hyypiä Timo
Published: June 2005

Recombinant viruses, constructed by exchanging the 5′ non-coding region (5′NCR), structural and non-structural protein coding sequences were used to investigate determinants responsible for differences between coxsackievirus A9 (CAV9) and coxsackievirus B3 (CBV3) infections in adult mice and two cell lines. Plaque assay titration of recombinant and parental viruses from different tissues from adult BALB/c mice demonstrated that the structural region of CBV3 determined tropism to the liver tissue due to receptor recognition, and the 5′NCR of CBV3 enhanced viral multiplication in the mouse pancreas. Infection with a chimeric virus, containing the structural region from CBV3 and the rest of the genome from CAV9, and the parental CBV3 strain, caused high levels of viraemia in adult mice. The ability of these viruses to infect the central nervous system suggested that neurotropism is associated with high replication levels and the presence of the CBV3 capsid proteins, which also enhanced formation of neutralizing antibodies. Moreover, the appearance of neutralizing antibodies correlated directly with the clearance of the viruses from the tissues. These results demonstrate potential pathogenicity of intraspecies recombinant coxsackieviruses, and the complexity of the genetic determinants underlying tissue tropism.
Human immunodeficiency virus 1 (HIV-1) envelope-dependent cell–cell fusion modulation by HIV-positive sera is related to disease progression
Authors: Huerta L. , Gómez-Icazbalceta G. , Soto-Ramírez L. , Viveros-Rogel M. , Rodríguez R. , Fuentes L. , Lamoyi E. , Larralde C.
Published: June 2005

Fusion of CD4+cells by HIV-1 envelope proteins (Env) is a mechanism of virus spread and cell damage. Production of antibodies able to influence cell–cell fusionin vivomay affect the course of the infection. The effect of sera from 49 HIV-1-positive patients was tested on anin vitrofusion assay using Env-expressing and normal Jurkat T cells labelled with DiI and DiO dyes, and flow cytometry for quantification of cell–cell fusion. Sera varied in their activity on fusion: 69·4 % inhibited, 24·5 % had no effect and 6·1 % enhanced cell fusion. Fusion activity correlated positively with the CD4+T-cell count and inversely with the viral load. Removal of IgG or IgM from sera reduced or eliminated inhibition and enhancing activities, respectively. Antibodies with inhibitory activity predominate in early and intermediate stages of infection, whereas loss of inhibition or enhancement of fusion correlates with progression to AIDS.
Binding and entry characteristics of porcine circovirus 2 in cells of the porcine monocytic line 3D4/31
Authors: Misinzo G. , Meerts P. , Bublot M. , Mast J. , Weingartl H. M. , Nauwynck H. J.
Published: June 2005

Porcine circovirus 2 (PCV2) is associated with post-weaning multisystemic wasting syndrome and reproductive problems in pigs. Cells of the monocyte/macrophage lineage are important target cells in PCV2-infected pigs, but the method of binding and entry of PCV2 into these cells is unknown. Therefore, binding and entry of PCV2 to the porcine monocytic cell line 3D4/31 were studied by visualization of binding and internalization of PCV2 virus-like particles (VLPs) by confocal microscopy and chemical inhibition of endocytic pathways (clathrin- and caveolae-mediated endocytosis and macropinocytosis), followed by evaluation of the level of PCV2 infection. It was shown that PCV2 VLPs bound to all cells, with maximal binding starting from 30 min post-incubation. Bound PCV2 VLPs were internalized in 47±5·0 % of cells. Internalization was continuous, with 70·5±9·7 % of bound PCV2 VLPs internalized at 360 min post-incubation. Internalizing PCV2 VLPs co-localized with clathrin. PCV2 infection was decreased significantly by chemical inhibitors that specifically blocked (i) actin-dependent processes, including cytochalasin D (75·5±7·0 % reduction) and latrunculin B (71·0±3·0 % reduction), and (ii) clathrin-mediated endocytosis, including potassium depletion combined with hypotonic shock (50·2±6·3 % reduction), hypertonic medium (56·4±5·7 % reduction), cytosol acidification (59·1±7·1 % reduction) and amantadine (52·6±6·7 % reduction). Inhibiting macropinocytosis with amiloride and caveolae-dependent endocytosis with nystatin did not decrease PCV2 infection significantly. PCV2 infection was reduced by the lysosomotropic weak bases ammonium chloride (47·0±7·9 % reduction) and chloroquine diphosphate (49·0±5·6 % reduction). Together, these data demonstrate that PCV2 enters 3D4/31 cells predominantly via clathrin-mediated endocytosis and requires an acidic environment for infection.
The 3a protein of severe acute respiratory syndrome-associated coronavirus induces apoptosis in Vero E6 cells
Authors: Law Patrick T. W. , Wong Chi-Hang , Au Thomas C. C. , Chuck Chi-Pang , Kong Siu-Kai , Chan Paul K. S. , To Ka-Fai , Lo Anthony W. I. , Chan Judy Y. W. , Suen Yick-Keung , Chan H. Y. Edwin , Fung Kwok-Pui , Waye Mary M. Y. , Sung Joseph J. Y. , Lo Y. M. Dennis , Tsui Stephen K. W.
Published: June 2005

An outbreak of severe acute respiratory syndrome (SARS) occurred in China and the first case emerged in mid-November 2002. The aetiological agent of this disease was found to be a previously unknown coronavirus, SARS-associated coronavirus (SARS-CoV). The detailed pathology of SARS-CoV infection and the host response to the viral infection are still not known. The 3a gene encodes a non-structural viral protein, which is predicted to be a transmembrane protein. In this study, it was shown that the 3a protein was expressed in the lungs and intestinal tissues of SARS patients and that the protein localized to the endoplasmic reticulum in 3a-transfected monkey kidney Vero E6 cells. In vitro experiments of chromatin condensation and DNA fragmentation suggested that the 3a protein may trigger apoptosis. These data showed that overexpression of a single SARS-CoV protein can induce apoptosis in vitro.
Novel mechanism of immunosuppression by influenza virus haemagglutinin: selective suppression of interleukin 12 p35 transcription in murine bone marrow-derived dendritic cells
Authors: Noone Cariosa M. , Lewis Ellen A. , Frawely Anne B. , Newman Robert W. , Mahon Bernard P. , Mills Kingston H. , Johnson Patricia A.
Published: June 2005

Infection with influenza virus strongly predisposes an individual to bacterial superinfection, which is often the significant cause of morbidity and mortality during influenza epidemics. Little is known about the immunomodulating properties of the virus that lead to this phenomenon, but the effect of the viral components on the development of immune dendritic cells (DCs) may prove vital. In this study, activation of and cytokine secretion by bacterial lipopolysaccharide (LPS)-stimulated bone marrow-derived dendritic cells (BMDCs) following treatment with the influenza virus major antigen haemagglutinin (HA) were examined. HA selectively inhibits the release of LPS-induced interleukin 12 (IL12) p70, which is independent of IL10 secretion. Suppression occurs at the transcriptional level, with selective inhibition of p35- and not p40-subunit mRNA expression. The downregulation of IL12 p70 by influenza HA is a novel and unexplored pathway that may be relevant in the predisposition to bacterial superinfection associated with influenza virus infections.
Gene-expression profiling of White spot syndrome virus in vivo
Authors: Marks Hendrik , Vorst Oscar , van Houwelingen Adèle M. M. L. , van Hulten Mariëlle C. W. , Vlak Just M.
Published: June 2005

White spot syndrome virus, type species of the genus Whispovirus in the family Nimaviridae, is a large, double-stranded DNA (dsDNA) virus that infects crustaceans. The genome of the completely sequenced isolate WSSV-TH encodes 184 putative open reading frames (ORFs), the functions of which are largely unknown. To study the transcription of these ORFs, a DNA microarray was constructed, containing probes corresponding to nearly all putative WSSV-TH ORFs. Transcripts of 79 % of these ORFs could be detected in the gills of WSSV-infected shrimp (Penaeus monodon). Clustering of the transcription profiles of the individual genes during infection showed two major classes of genes: the first class reached maximal expression at 20 h post-infection (p.i.) (putative early) and the other class at 2 days p.i. (putative late). Nearly all major and minor structural virion-protein genes clustered in the latter group. These data provide evidence that, similar to other large, dsDNA viruses, the WSSV genes at large are expressed in a coordinated and cascaded fashion. Furthermore, the transcriptomes of the WSSV isolates WSSV-TH and TH-96-II, which have differential virulence, were compared at 2 days p.i. The TH-96-II genome encodes 10 ORFs that are not present in WSSV-TH, of which at least seven were expressed in P. monodon as well as in crayfish (Astacus leptodactylus), suggesting a functional but not essential role for these genes during infection. Expression levels of most other ORFs shared by both isolates were similar. Evaluation of transcription profiles by using a genome-wide approach provides a better understanding of WSSV transcription regulation and a new tool to study WSSV gene function.
A new subtype (subgenotype) Ac (A3) of hepatitis B virus and recombination between genotypes A and E in Cameroon
Authors: Kurbanov Fuat , Tanaka Yasuhito , Fujiwara Kei , Sugauchi Fuminaka , Mbanya Dora , Zekeng Leopold , Ndembi Nicaise , Ngansop Charlotte , Kaptue Lazare , Miura Tomoyuki , Ido Eiji , Hayami Masanori , Ichimura Hiroshi , Mizokami Masashi
Published: June 2005

Blood samples (n=544) from two different populations (Pygmies and Bantus) in Cameroon, West Africa, were analysed. Serological tests indicated that the anti-hepatitis C virus (HCV) prevalence in Bantus (20·3 %) was higher than that in Pygmies (2·3 %, P<0·0001), whereas the distribution of hepatitis B virus (HBV) serological markers was equally high in both populations: in total, 9·4, 17·3 and 86·8 % for HBsAg, anti-HBs and anti-HBc, respectively. HBV genotype A (HBV/A) and HBV/E were predominant (43·5 % each) in both populations, and HBV/D was found in a minority (13 %). The preS/S region was sequenced in nine cases (five HBV/A and four HBV/E) and the complete genome in six cases (four HBV/A and two HBV/E). Subsequent phylogenetic analysis revealed that the HBV/A strains were distinct from the subtypes (subgenotypes) described previously, Ae (A2) and Aa (A1), and in the preS/S region they clustered with previously reported sequences from Cameroon. Based on the nucleotide difference from Aa (A1) and Ae (A2), more than 4 % in the complete genome, the Cameroonian strains were suggested to represent a new subtype (subgenotype), designated HBV/Ac (A3). A high (3·9 %) nucleotide divergence in HBV/Ac (A3) strains suggested that the subtype (subgenotype) has a long natural history in the population of Cameroon. One of the HBV/Ac (A3) strains was found to be a recombinant with an HBV/E-specific sequence in the polymerase reverse transcriptase domain. Further cohort studies will be required to assess detailed epidemiological, virological and clinical characteristics of HBV/Ac (A3), as well as its recombinant form.
Characterization of Potato virus Y (PVY) molecular determinants involved in the vein necrosis symptom induced by PVYN isolates in infected Nicotiana tabacum cv. Xanthi
Authors: Tribodet Michel , Glais Laurent , Kerlan Camille , Jacquot Emmanuel
Published: June 2005

Viral molecular determinant(s) involved in the tobacco vein necrosis (TVN) symptom induced by necrotic isolates of Potato virus Y (PVY) on Nicotiana tabacum cv. Xanthi leaves remain undetermined. Reference isolates belonging to PVYN (infectious PVYN-605 clone) and PVYO (PVYO-139) were used to produce PVY chimeric genomes by using reverse-genetic techniques. These chimeric clones were inoculated biolistically onto Nicotiana clevelandii plants to establish the clone, prior to being tested on N. tabacum for their ability to induce TVN symptoms. Comparison between sequence data and symptoms observed for each mutated PVY construct shows that the C-terminal part of the multifunctional HC-Pro protein includes two residues (K400 and E419) that are involved in TVN induced by PVYN isolates. Site-directed mutagenesis was used to confirm that these two HC-Pro residues are involved in the TVN phenotype.
Genome sequence of Chrysodeixis chalcites nucleopolyhedrovirus, a baculovirus with two DNA photolyase genes
Authors: van Oers Monique M. , Abma-Henkens Marleen H. C. , Herniou Elisabeth A. , de Groot Joost C. W. , Peters Sander , Vlak Just M.
Published: June 2005

The complete genome sequence of a single nucleocapsid nucleopolyhedrovirus recently isolated from Chrysodeixis chalcites (ChchNPV) was determined. The viral genome has a size of 149 622 bp and an overall G+C content of 39·1 mol%. The sequence contains 151 predicted open reading frames (ORFs) with a minimal size of 50 codons. The similarity of these ORFs with those of other completely sequenced baculoviruses was calculated using a newly developed database, named gecco. Phylogenetic analysis of the whole genome confirmed the evolutionary relationship of ChchNPV with group II NPVs, as did the absence of the NPV group I-specific gp64 gene. It is the first group II NPV to encode proliferating cell nuclear antigen. Most noteworthy is the presence of two ORFs encoding a class II cyclobutane pyrimidine dimer DNA photolyase. These two ORFs share only 45 % amino acid identity and have different promoter motifs. Twenty-two additional unique baculovirus genes were identified, including a gene encoding a novel putative RING finger protein with a possible homologue in poxviruses.
Mosquito vectors of the 1998–1999 outbreak of Rift Valley Fever and other arboviruses (Bagaza, Sanar, Wesselsbron and West Nile) in Mauritania and Senegal
Authors: Diallo M. , Nabeth P. , Ba K. , Sall A. A. , Ba Y. , Mondo M. , Girault L. , Abdalahi M. O. , Mathiot C.
Published: June 2005

Abstract.  Following an outbreak of Rift Valley fever (RVF) in south‐eastern Mauritania during 1998, entomological investigations were conducted for 2 years in the affected parts of Senegal and Mauritania, spanning the Sénégal River basin. A total of 92 787 mosquitoes (Diptera: Culicidae), belonging to 10 genera and 41 species, were captured in light traps. In Senegal, Culex poicilipes (41%) and Mansonia uniformis (39%) were the most abundant species caught, whereas Aedes vexans (77%) and Cx. poicilipes (15%) predominated in Mauritania. RVF virus was isolated from 63 pools of Cx. poicilipes: 36 from Senegal in 1998 and 27 from Mauritania in 1999. These results are the first field evidence of Cx. poicilipes naturally infected with RVFV, and the first isolations of this virus from mosquitoes in Mauritania – the main West African epidemic and epizootic area. Additional arbovirus isolates comprised 25 strains of Bagaza (BAG) from Aedes fowleri, Culex neavei and Cx. poicilipes; 67 Sanar (ArD 66707) from Cx. poicilipes; 51 Wesselsbron (WSL) from Ae. vexans and 30 strains of West Nile (WN) from Ma. uniformis, showing differential specific virus–vector associations in the circulation activity of these five arboviruses.
Energy partnership: China and the Gulf States
Authors: Bahgat Gawdat
Published: June 2005

One of the most significant developments in the global energy market in the last several years has been China's skyrocketing demand for energy. In 1993, China became a net oil importer for the first time in its history and in 2003 replaced Japan as the world's second‐largest oil importer (after the United States). The country needs more energy to maintain its spectacular economic performance.

This study examines China's attempts to satisfy its growing needs for oil and natural gas by increasing imports from Russia and Central Asia/Caspian Sea region. The analysis suggests that despite growing cooperation between the two sides, the Gulf region is likely to satisfy most of China's hydrocarbons needs. Energy partnership between China and the Gulf has already started and is likely to be consolidated over the next few decades. The study also argues that this growing partnership between China and the Gulf should not be seen as a threat to any third party. The global energy market is well‐integrated. Energy policy should not be seen in zero‐sum terms. A China‐Gulf partnership will benefit both sides and contribute to the stability of global energy markets.
Treatment of Guillain‐Barré syndrome and CIDP
Authors: Van Doorn Pieter A.
Published: June 2005

Abstract  Guillain‐Barré syndrome (GBS) and chronic inflammatory demyelinating poly‐(radiculo)neuropathy (CIDP) are immune‐mediated disorders with a variable duration of progression and a range in severity of weakness. Infections can trigger GBS and exacerbate CIDP. Anti‐ganglioside antibodies are important, but there is debate on the role of genetic factors in the pathogenesis of these disorders. Randomized controlled trials (RCT) have shown that intravenous immunoglobulin (IVIg) and plasma exchange (PE) are effective in both GBS and CIDP. Most CIDP patients also improve after steroid therapy. Despite current treatment options, many patients have residual deficits or need to be treated for a long period of time. Therefore, new treatment trials are highly indicated. This review focuses on the current and possible new treatment options that could be guided by recent results from laboratory experiments.
Laminins and their receptors in Schwann cells and hereditary neuropathies
Authors: Feltri Maria Laura , Wrabetz Lawrence
Published: June 2005

Abstract  This review focuses on the influence of laminins, mediated through laminin receptors present on Schwann cells, on peripheral nerve development and pathology. Laminins influence multiple aspects of cell differentiation and tissue morphogenesis, including cell survival, proliferation, cytoskeletal rearrangements, and polarity. Peripheral nerves are no exception, as shown by the discovery that defective laminin signals contribute to the pathogenesis of diverse neuropathies such as merosin‐deficient congenital muscular dystrophy and Charcot‐Marie‐Tooth 4F, neurofibromatosis, and leprosy. In the last 5 years, advanced molecular and cell biological techniques and conditional mutagenesis in mice began revealing the role of different laminins and receptors in developing nerves. In this way, we are starting to explain morphological and pathological observations beginning at the start of the last century. Here, we review these recent advances and show how the roles of laminins and their receptors are surprisingly varied in both time and place.
Impaired peripheral nerve regeneration in diabetes mellitus
Authors: Kennedy James M. , Zochodne Douglas W.
Published: June 2005

Abstract  Diabetes mellitus impairs peripheral nerve regeneration. Regenerative failure likely exacerbates deficits from polyneuropathy or focal neuropathies in patients who might otherwise exhibit spontaneous improvement. Some focal neuropathies, like carpal tunnel syndrome, are common, yet render ongoing disability because of their delayed recovery. Why diabetic nerves fail to regenerate is an interesting question to consider because several mechanisms likely contribute. In this review, we examine a number of these causes. These causes include microangiopathy or disease of small blood vessels, failure to provide proper metabolic support for repair, defects in the entry and actions of inflammatory cells within the injury milieu, less robust support of axons by their Schwann cells, and lack of a full repertoire of trophic factors. A number of the mechanisms that generate neuropathy in the first place also likely contribute to failed regenerative programs, but how they do so is not clear.
Harmful effects of anti‐GalNAc‐GD1a antibodies and TNF‐α on rat dorsal root ganglia
Authors: Kamakura Keiko , Kaida Ken‐ichi , Kusunoki Susumu , Miyamoto Norikazu , Masaki Toshihiro , Nakamura Ryohji , Motoyoshi Kazuo , Fukuda Jun
Published: June 2005

Abstract  The clinical characteristics of five (22%) of 23 patients with Guillain‐Barré syndrome (GBS), whose serum contained immunoglobulin G (IgG) antibodies to the ganglioside N‐acetylgalactosaminyl GD1a (GalNAc‐GD1a), included pure motor weakness of the axonal type. These patients had a relatively good prognosis, but displayed higher serum tumor necrosis factor‐alpha (TNF‐α) titers than the other GBS patients. We examined the effect of serum from these patients with IgG anti‐GalNAc‐GD1a antibodies on neurites from cultured rat dorsal root ganglia (DRG) and found it to damage the myelin in well‐elongated DRG neurites and monolayer cultures of Schwann cells and neurons. In the regeneration model, serum from these patients delayed neurite extension and inhibited Schwann cell proliferation. Neurons in cultured monolayers showed vacuolation and decreased rapidly in number. Schwann cells were also vacuolated and readily detached from the substratum. The effects of IgG anti‐GalNAc‐GD1a antibodies purified from one of the patients, rabbit serum after immunization with GalNAc‐GD1a, and recombinant TNF‐α were also examined. IgG anti‐GalNAc‐GD1a antibodies mainly inhibited the regeneration and preservation of neurons, while TNF‐α mainly induced morphological changes in well‐proliferated Schwann cells and myelin.
TEL/ETV6 accelerates erythroid differentiation and inhibits megakaryocytic maturation in a human leukemia cell line UT‐7/GM
Authors: Takahashi Wataru , Sasaki Ko , Komatsu Norio , Mitani Kinuko
Published: June 2005

TEL/ETV6 accelerates erythroid differentiation in the murine erythroleukemia cell line. To clarify the effects of TEL on megakaryocytic maturation as well as erythroid differentiation, we chose the human leukemia cell line UT‐7/GM that differentiates into the erythroid and megakaryocytic lineages by treatment with erythropoietin and thrombopoietin, respectively. Upon erythropoietin exposure, overexpressed TEL stimulated hemoglobin synthesis and accumulation of the erythroid differentiation‐specific transcripts such as γ‐globin, δ‐aminolevulinic acid synthase‐erythroid, and erythropoietin receptor. Moreover, the glycophorin A(+)/glycoprotein IIb(–) fraction appeared more rapidly in the TEL‐overexpressing cells. Interestingly, overexpression of TEL was associated with lower levels of the megakaryocytic maturation‐specific glycoprotein IIb and platelet factor 4 transcripts under the treatment with thrombopoietin. Consistently, the glycophorin A(–)/glycoprotein IIb(+) fraction increased more slowly in the TEL‐overexpressing cells. Finally, expression of endogenous TEL proteins in UT‐7/GM cells was down‐regulated following erythropoietin and thrombopoietin exposure. All these data suggest that TEL may decide the fate of human erythrocyte/megakaryocyte common progenitors to differentiate towards the erythroid lineage and against the megakaryocytic lineage. (Cancer Sci 2005; 96: 340–348)
Nano‐sized fluorescent particles as new tracers for sentinel node detection: Experimental model for decision of appropriate size and wavelength
Authors: Nakajima Morio , Takeda Motohiro , Kobayashi Masaki , Suzuki Satoshi , Ohuchi Noriaki
Published: June 2005

The concepts of made‐to‐order and low‐invasiveness medicines are becoming widely accepted. A treatment for cancer, with minimum invasive surgery and without lymph nodes dissection based on sentinel lymph node (SN) navigation surgery, would adhere to these concepts. Dyes and/or radioisotopes are employed for SN detection in standard methods, however, each detection method has advantages and disadvantages. To make up for the disadvantages, we aimed at developing a new non‐invasive method using fluorescent beads of uniform nano‐size that could efficiently visualize SN from outside the body, and conducted experiments to determine the appropriate size and fluorescent wavelength. We examined various bead sizes and fluorescent wavelengths. The sizes were 20, 40, 100 and 200 nm. The fluorescent peak wavelengths of the beads were yellow‐green (515 nm), dark red (680 nm), far red (720 nm) and infrared (755 nm). The beads were subcutaneously injected into the foot pad of the hind leg of a rat, and followed by laser scanning of the inguinal area for fluorescence observation. The beads exhibited different times for the fluorescence detection according to their sizes and wavelength. The 40 nm beads were considered to be the most appropriate size for SN detection in rats. The wavelength of near infrared was effective for avoiding attenuation by the tissue. In conclusion, we confirmed that uniformly nano‐sized fluorescent beads have the potential to be an alternative to existing tracers in the detection of the SN in animal experiments if we select the appropriate particle size and wavelength. (Cancer Sci 2005; 96: 353–356)
Cytotoxic effects of pemetrexed in gastric cancer cells
Authors: Kim Jee Hyun , Lee Keun‐Wook , Jung Yeonjoo , Kim Tai Young , Ham Hye Seon , Jong Hyun‐Soon , Jung Kyung Hae , Im Seock‐Ah , Kim Tae‐You , Kim Noe Kyeong , Bang Yung‐Jue
Published: June 2005

Pemetrexed is a newly developed multitargeted antifolate with promising clinical activity in many solid tumors including gastric cancer. The aim of the present study was to evaluate the cytotoxicity of pemetrexed and its mode of interaction with cisplatin in gastric cancer cell lines, and to identify genes associated with sensitivity to pemetrexed. The cytotoxic activity of pemetrexed was assessed by tetrazolium‐based colorimetric assay (MTT assay) and the interaction between pemetrexed and cisplatin was evaluated by the isobologram method. Western immunoblotting and real time RT‐PCR analysis of thymidylate synthase (TS), folylpoly‐γ‐glutamate synthetase (FPGS) and reduced folate carrier (RFC1) were performed in order to determine whether sensitivity to pemetrexed would be predictable by protein or mRNA expression levels. Pemetrexed was more cytotoxic than 5‐fluorouracil, with IC50 between 17 and 310 nM in most of the gastric cancer cell lines examined and the pemetrexed/cisplatin combination resulted in additive or synergistic interaction. The protein expressions of TS, FPGS, and RFC1 were significantly associated with IC50 for 5‐fluorouracil, but no such association was found for pemetrexed chemosensitivity. The mRNA expressions of RFC1, FPGS and other target and resistance related genes revealed no significant association with pemetrexed sensitivity. In conclusion, pemetrexed is active against gastric cancer cell lines and the pemetrexed/cisplatin combination showed a synergistic or additive interaction, supporting its clinical use in gastric cancer. Drug sensitivity toward pemetrexed could not be predicted by the expressions of TS, RFC1, or FPGS and we suggest that it is determined by interactions between multiple genes. (Cancer Sci 2005; 96: 365–371)
Frequent KIT and epidermal growth factor receptor overexpressions in undifferentiated‐type breast carcinomas with ‘stem‐cell‐like’ features
Authors: Tsuda Hitoshi , Tani Yoichi , Weisenberger Joel , Kitada Shigehiro , Hasegawa Tadashi , Murata Tetsuya , Tamai Seiichi , Hirohashi Setsuo , Matsubara Osamu , Natori Tsuneo
Published: June 2005

It was hypothesized that four histopathological types or subtypes of breast carcinoma were undifferentiated types characterized by bidirectional differentiation toward both luminal epithelial and myoepithelial cells and had characteristic molecular changes: invasive ductal carcinoma (IDC) with a large central acellular zone, atypical medullary carcinoma (a subgroup in Grade 3 solid‐tubular carcinoma), matrix‐producing carcinoma, and spindle‐cell carcinoma (or carcinoma with spindle‐cell metaplasia). In 32 cases of the undifferentiated type and 37 cases of the relatively differentiated types, we immunohistochemically examined the expressions of myoepithelial markers and KIT, epidermal growth factor receptor (EGFR), and c‐erbB‐2 oncoproteins. Vimentin, S‐100, and α‐smooth muscle actin were positive in 28 (88%), 22 (69%), and 15 (47%) of the undifferentiated types, but were positive in seven (19%), one (3%), and one (3%) of relatively differentiated types (P < 0.0001). KIT and EGFR overexpressions were detected more frequently in the undifferentiated types (34 and 88%, respectively) than in relatively differentiated types (3 and 3%, respectively) (P < 0.0001, for both). In 11 (85%) of 13 cases with KIT overexpression, EGFR overexpression concurred. c‐erbB‐2 overexpression was almost equally detected in both the undifferentiated and relatively differentiated types, and did not correlate with KIT or EGFR overexpression. Phosphotyrosine was detected in 16 (67%) of 24 cases with KIT, EGFR, and/or c‐erbB‐2 overexpression but only in six (18%) of 34 cases without KIT, EGFR, or c‐erbB‐2 overexpression (P = 0.0002). The undifferentiated‐type breast carcinomas appeared to show mammary epithelial stem cell‐like features, and they could be identified by KIT and/or EGFR overexpressions. (Cancer Sci 2005; 96: 333–339)
Interferon-γ is produced by CD8+ T cells in response to HLA-A24-restricted hepatitis C virus epitopes after sustained virus loss
Authors: Kobayashi K , Ishii M , Shiina M , Ueno Y , Kondo Y , Kanno A , Miyazaki Y , Yamamoto T , Kobayashi T , Niitsuma H , Kikumoto Y , Takizawa H , Shimosegawa T
Published: June 2005

Differences in cytotoxic T lymphocyte activity in hepatitis C virus infection may account for the outcome of interferon monotherapy. To investigate this hypothesis, we analysed the response of peripheral CD8+ T cells that recognized epitopes presented by HLA-A*2402. We synthesized HLA/β2-microglobulin/peptide complexes using two epitopes. Production of interferon-γ by CD8+ T cells in response to plastic-bound monomeric HLA/peptide complex was observed frequently in sustained virus responders (SVR) (n = 13) against all the peptides, NS31296–1304 (the percentage of responding patients, 61.5%) and core 129–137 (53.8%), while no interferon-γ production was observed in non-responders (NR) (n = 13) for any of the peptides. Tetramer-staining showed the presence of CD8+ T cells specific for all the peptides except NS31296–1304 in two SVR at the end of interferon monotherapy, although hardly any such cells were found in four NR. Specific killing was observed against peptides NS31296–1304 (3/4) and core 129–137 (1/4) in sustained responders but none in non-responders. These results suggest that the responses of cytotoxic T lymphocytes (CTLs) were induced during interferon therapy in these patients and that interferon-γ production by CD8+ T lymphocytes against HCV NS31296–1304 and core 129–137 are well maintained in patients with SVR compared with those with NR. These findings emphasize the importance of the CD8+ T cell response in controlling HCV infection.
Natural killer cell activity in families of patients with systemic lupus erythematosus: demonstration of a killing defect in patients
Authors: Green M R J , Kennell A S M , Larche M J , Seifert M H , Isenberg D A , Salaman M R
Published: June 2005

Natural killer (NK) cell cytotoxic activity and cell frequency, expressed as a percentage of total lymphocytes, have been determined in peripheral blood mononuclear cells from first-degree relatives of patients with systemic lupus erythematosus (SLE), the patients themselves, a group of rheumatoid arthritis (RA) patients and controls. Low levels of killing activity relative to controls were found in some members of all groups with the extent of depression falling into two ranges. Moderate reductions were seen in female (3/31, 10%) and male (4/14, 29%) relatives of SLE patients, female (12/60, 20%) and male (3/4, 75%) SLE patients and female RA patients (6/17, 35%). A more profound depression of killing activity was confined to other female SLE patients (15/60, 25%). There were strong correlations in all groups between killing activity and percentage of NK cells, but analysis of the ratio of these parameters and studies with purified preparations of NK cells suggest that the reduced activity in SLE frequently involves a defect in the killing capacity of the individual cells in addition to the reduced levels of NK cells. Azathioprine (AZA), which was used in treatment of 12 SLE patients, was invariably associated with low values of killing activity. It appears to substantially reduce the percentage of NK and B cells in an action unconnected with the NK cell abnormalities associated with SLE. The finding of low killing activity in relatives and a correlation between their activity and that of their patients support the view that NK cell deficiency is a genetic determinant of SLE. NK cells in SLE may produce insufficient levels of cytokines required for the regulation of IgG production.
Sustained activation of neutrophils in the course of Kawasaki disease: an association with matrix metalloproteinases
Authors: Biezeveld M H , Van Mierlo G , Lutter R , Kuipers I M , Dekker T , Hack C E , Newburger J W , Kuijpers T W
Published: June 2005

Kawasaki disease (KD) is an acute febrile syndrome of childhood, characterized by vasculitis of the medium-sized arteries. White blood cell counts and the inflammatory parameter C-reactive protein (CRP) are known to be elevated in the acute phase of the disease. In this study we investigated the course of inflammatory cell type-specific parameters in KD over a longer period of time. Plasma levels of human neutrophil elastase (HNE), matrix metalloproteinases-2 and -9 (MMP2, MMP9), and neutrophil gelatinase-associated lipocalin (NGAL), macrophage neopterin and CRP were measured. Plasma samples were collected in the acute, subacute and early convalescent stage, and three months after the onset of disease. Median CRP and neopterin normalized within two weeks. In contrast, six weeks and three months after onset of disease, levels of HNE were still elevated, with median values of 163 ng/ml and 156 ng/ml, respectively (control children median < 50 ng/ml; for all time-points P < 0·0001). Values of NGAL correlated with the levels of HNE (r = 0·39, P = 0·013). These results demonstrate a longer state of neutrophil activation in KD than was previously assumed. The potential relationship between this prolonged neutrophil activation, coronary artery lesion formation and their persistence, as well as the risk of premature atherosclerosis warrants further evaluation.
Biotic diversification in the Guayana Highlands: a proposal
Authors: Rull V.
Published: June 2005

Until recently, the high degree of diversity and endemism of the Guayana Highlands was explained within the frame of the refuge theory. Although this hypothesis is unsupported by recent palaeoecological evidence, no new diversification model has been proposed. This paper is a proposal based on the latest palynological findings that indicate a downward biotic migration of c. 1100 m altitude during glacials, and the subsequent interglacial upward shift, in response to colder and warmer climates, respectively. Therefore, during glacials, biotic mixing is expected in the lowlands, thus promoting sympatric speciation, hybridization and polyploidy. At the mountaintops, unknown cold‐adapted taxa and páramo‐like(?) communities are expected to have occurred, and vicariance prevailed. In the interglacials, many taxa have had the opportunity for ascending to the mountains again, allowing genetic interchange among their slopes and summits, while others would have been adapted to lowlands. The interglacial highland communities, where vicariance still predominated, experienced some extinction owing to habitat loss by upland displacement. According to this model, the successive alternation of glacials and interglacials resulted in a net increase of diversity and endemism, favoured by the complex topography and habitat heterogeneity, which allowed high niche diversification. This model has some similarities with the Andean and Amazon modes of diversification, but the special topographical characteristics of the Guayana region made it different in other fundamental aspects. The Guayana Highlands would have acted as a ‘biodiversity pump’ for the surrounding inner and coastal lowlands, due to the repeated speciation and further spreading events, as a response to climate. Several working hypotheses are suggested in relation to the proposed model. The use of coordinated international multiproxy projects combining palaeoecology and genetic analysis of modern taxa is strongly encouraged for exploring these ideas.
Light microscopic identification and semiquantification of polyethylene particles in methylmethacrylate and paraffin‐embedded experimental bone implant specimens
Authors: RAHBEK O. , KOLD S. , OVERGAARD S. , SOBALLE K.
Published: June 2005

The aim of this study was to evaluate the identification of polyethylene (PE) particles in relatively thick methylmethacrylate (MMA) sections widely used in bone implant research. The sensitivity and specificity were compared between decalcified paraffin‐embedded oil red O (ORO) stained and MMA‐embedded sections using polarized light. Furthermore, we introduced a grading system to semiquantify the level of PE particles in peri‐implant tissue. Paraffin‐embedded and MMA‐embedded sections were compared concerning intra‐observer agreement of the grading system. Moreover, the semiquantitative assessment of particle level was compared between the two section types.

We found a sensitivity and specificity of polarized light of 100% for both paraffin ORO‐stained and MMA sections. The intra‐observer agreement on both types was comparable and acceptable. The ratings of differently processed blocks (MMA‐ and paraffin‐embedded) originating from the same bone implant specimen showed good correlation.

Our study showed that relatively thick MMA sections were just as suitable as ORO‐stained paraffin sections concerning peri‐implant PE particle migration analysis. MMA sections do not allow analysis at cellular level, but unbiased estimation of bone ingrowth into the implant surface based on stereological principles is possible.
Immobilization and condensation of DNA with 3‐aminopropyltriethoxysilane studied by atomic force microscopy
Authors: LIU Z. , LI Z. , ZHOU H. , WEI G. , SONG Y. , WANG L.
Published: June 2005

We used different methods to modify a mica surface with 3‐aminopropyltriethoxysilane (APTES), and then used it as substrate to immobilize DNA for atomic force microscopy (AFM) observation. The evaporation method and solution modifying method were investigated and evaluated. The solution modifying method was found to be relatively simple and effective. Using an APTES solution‐modified mica surface, DNA immobilization appeared more reproducible and it could be imaged in liquid. The mixed solution of APTES and DNA was dropped directly onto the mica surface for AFM imaging. We found that DNA can condense in APTES water solutions. Toroids, rods and intermediate structures of condensation were captured by AFM.
Maternal body composition, offspring blood pressure and the hypothalamic‐pituitary‐adrenal axis
Authors: Phillips David I. W. , Bennett Franklyn I. , Wilks Rainford , Thame Minerva , Boyne Michael , Osmond Clive , Forrester Terrence E.
Published: June 2005

We tested the hypothesis that women who are thin or have poor pregnancy weight gain have offspring with higher blood pressure and examined whether this link is mediated by increased secretion of cortisol. We studied a cohort of 388 children born in Kingston, Jamaica. From hospital records we obtained information about their mother's body mass index (BMI) and weight gain during pregnancy. At age 8.5 years we measured the children's fasting plasma cortisol concentrations and blood pressure and assessed their mother's anthropometry. There were no relationships between the mother's BMI or weight gain during pregnancy and offspring blood pressure. However, mothers with a greater subscapular to triceps skinfold thickness ratio (SSTR) had offspring with higher blood pressure (5.6 mmHg systolic and 3.7 mmHg diastolic increase per unit change in SSTR, P = 0.002 and P = 0.008 respectively). Fasting plasma cortisol concentrations correlated with the children's systolic (r = 0.33, P < 0.0001) and diastolic pressures (r = 0.12, P = 0.02) independently of age, gender, weight or socio‐economic status and were also predicted by the mother's SSTR. These findings suggest that maternal truncal obesity rather than thinness is associated with raised blood pressure in the offspring, and that this link may be mediated by increased cortisol secretion.
Effect of host genotype on leaf rust (Puccinia triticina) lesion development and urediniospore production in wheat seedlings
Authors: Rimé D. , Robert C. , Goyeau H. , Lannou C.
Published: June 2005

Experiments were performed in controlled conditions to compare several aggressiveness components of an isolate of Puccinia triticina on different wheat (Triticum aestivum) genotypes. Latency period, urediniospore production per lesion and per unit of sporulating surface, lesion size, and nitrogen and carbon content of the spores were measured on four host genotypes. Three of the host cultivars (Soissons, Altria and Isengrain) were susceptible and the fourth (Trémie) was resistant to the isolate used in the experiments, producing a mesothetic infection type. In all the analyses, lesion density was used as a covariable. The latent period was identical on the susceptible host cultivars, and there were no marked differences in the urediniospore production capacity when related to the sporulating surface area. In cv. Isengrain, differences in lesion size relative to the other susceptible cultivars resulted in lower urediniospore production per lesion. Urediniospore production per lesion and lesion size were density dependent and decreased exponentially with increasing lesion density. Urediniospore production per unit of sporulating surface was either independent of lesion density or marginally dependent (decreased linearly with a limited rate). On the resistant cultivar, Trémie, the latent period was longer and of a much greater variance compared with the susceptible cultivars. Urediniospore production per lesion was considerably reduced, but this reduction was fully accounted for by a reduction in lesion size, the urediniospore production capacity of the diseased tissue remaining equivalent to that observed in the susceptible cultivars. In all cultivars the C and N contents of the urediniospores were considered unchanged, even if minor differences were detected.
PCR‐based detection of Xanthomonas campestris pathovars in Brassica seed
Authors: Berg T. , Tesoriero L. , Hailstones D. L.
Published: June 2005

Xanthomonas campestris is a seedborne bacterium that causes black rot of crucifers. Substantial crop losses may result from the rapid spread of the bacteria under favourable conditions, especially those occurring during seedling production. A PCR‐based method has been developed for the rapid and sensitive detection of the pathovars of X. campestris that affect crucifers. Primers were designed to specifically amplify a 619 bp fragment of the hrpF gene from X. campestris. Amplification products were not detected from other Xanthomonas species, or from other pathogenic or epiphytic bacteria occurring on these plants. To avoid false‐negative results arising from the presence of amplification inhibitors in plant extracts, primers targeting a 360 bp section of the internal transcribed spacer (ITS) region from Brassica spp. were included in a multiplex PCR. The assay readily detected X. campestris pv. campestris infections in diseased plants and from bacterial colonies isolated on growth media, and was more sensitive and specific than traditional plating methods and a commercially available ELISA. A seed‐washing protocol was optimized to allow the detection of a single artificially infected seed among 10 000 healthy seeds using the multiplex PCR.
Adjustment of soil‐surface pH and comparison with conventional fungicide treatments for control of lettuce drop (Sclerotinia minor)
Authors: Wilson C. R. , DeLittle J. A. , Wong J. A. L. , Schupp P. J. , Gibson L. J.
Published: June 2005

The use of soil‐surface applications of finely powdered calcium hydroxide (Ca(OH)2) to inhibit Sclerotinia minor sclerotial germination and infection at the collar region of lettuce plants is described. In the laboratory, a pH > 8·0 reduced sclerotial germination of the three S. minor isolates tested. In the glasshouse, surface applications of 2–10 t Ca(OH)2 ha−1 raised the pH of the top 1–2 cm of a duplex sandy loam soil above 8·5 for at least 8 weeks without affecting soil pH within the transplant root zone. There was a linear relationship between the rate of Ca(OH)2 applied and disease control, with complete disease suppression at 10 t Ca(OH)2 ha−1. In field trials on two soil types (duplex sandy loam, pH 6·0; and red ferrosol, pH 6·9), a rate of 2·5 t Ca(OH)2 ha−1, maintained soil‐surface pH above 8·5 for 1–3 weeks and provided up to 58% reduction in lettuce drop. Application of polyvinyl alcohol (a soil‐conditioning polymer) over the Ca(OH)2 layer appeared to reduce Ca(OH)2 loss by wind, but did not improve retention of raised soil‐surface pH or disease suppression. Ca(OH)2 treatment gave similar disease control to the industry standard treatment of a procymidone‐based fungicide seedling drench. A combined treatment of Ca(OH)2 and fungicide drench gave greater control than either individual treatment, and equivalent control to fungicide drench and three procymidone foliar sprays, offering integrated management options. The use of soil‐surface‐applied Ca(OH)2 with fungicides, rotation and drip irrigation offers an opportunity for enhanced and sustainable control of lettuce drop.