bluuebunny/crossref_metadata_2025 huggingface dataset:
Macrophages Kill Human Papillomavirus Type 16 E6-Expressing Tumor Cells by Tumor Necrosis Factor Alpha- and Nitric Oxide-Dependent Mechanisms
Authors: Routes John M. , Morris Kristin , Ellison Misoo C. , Ryan Sharon
Published: December 2004

The expression of adenovirus serotype 2 or 5 (Ad2/5) E1A sensitizes cells to killing by NK cells and activated macrophages, a property that correlates with the ability of E1A to bind the transcriptional coadaptor proteins p300-CBP. The E6 oncoproteins derived from the high-risk human papillomaviruses (HPV) interact with p300 and can complement mutant forms of E1A that cannot interact with p300 to induce cellular immortalization. Therefore, we determined if HPV type 16 (HPV16) E6 could sensitize cells to killing by macrophages and NK cells. HPV16 E6 expression sensitized human (H4 and C33A) and murine (MCA-102) cell lines to lysis by macrophages but not by NK cells. The lysis of cells that expressed E6 by macrophages was p53 independent but dependent on the production of tumor necrosis factor alpha (TNF-α) or nitric oxide (NO) by macrophages. Unlike cytolysis assays with macrophages, E6 expression did not significantly sensitize cells to lysis by the direct addition of NO or TNF-α. Like E1A, E6 has been reported to sensitize cells to lysis by TNF-α by inhibiting the TNF-α-induced activation of NF-κB. We found that E1A, but not E6, blocked the TNF-α-induced activation of NF-κB, an activity that correlated with E1A-p300 binding. In summary, Ad5 E1A and HPV16 E6 sensitized cells to lysis by macrophages. Unlike E1A, E6 did not block the ability of TNF-α to activate NF-κB or sensitize cells to lysis by NK cells, TNF-α, or NO. Thus, there appears to be a spectrum of common and unique biological activities that result as a consequence of the interaction of E6 or E1A with p300-CBP.
Role of Tumor Necrosis Factor Receptors in Regulating CD8 T-Cell Responses during Acute Lymphocytic Choriomeningitis Virus Infection
Authors: Suresh M. , Singh Anju , Fischer Christopher
Published: December 2004

The role of tumor necrosis factor (TNF) in regulating various phases of the antiviral T-cell response is incompletely understood. Additionally, despite strong evidence ascribing a role for TNF in protecting against T-cell-dependent autoimmunity, the underlying mechanisms are still obscure. To address these issues, we have investigated the role of tumor necrosis factor receptors (TNFRs) I (p55R) and II (p75R) in regulating CD8 T-cell responses to lymphocytic choriomeningitis virus (LCMV) with wild-type, p55R-deficient (p55−/−), p75R-deficient (p75−/−), and p55R- and p75R-deficient (DKO) mice. Loss of p55R increased the number of memory CD8 T cells to only one of the two immunodominant epitopes, and p75R deficiency had a minimal impact on the T-cell response to LCMV. Strikingly, deficiency of both p55R and p75R had a more dramatic effect on the LCMV-specific CD8 T-cell response; in the DKO mice, as a sequel to enhanced expansion and a reduction in contraction of CD8 T cells, there was a substantial increase in the number of memory CD8 T cells (specific to the two immunodominant epitopes). While the majority of LCMV-specific memory CD8 T cells in wild-type mice were CD62LhiCCR7hi(central memory), a major proportion of memory CD8 T cells in DKO mice were CD62LloCCR7hi. TNFR deficiency did not affect the proliferative renewal of memory CD8 T cells. Taken together, these data suggested that TNFRs p55R and p75R have overlapping roles in downregulating CD8 T-cell responses and establishment of immune homeostasis during an acute viral infection.
La Crosse Virus Nonstructural Protein NSs Counteracts the Effects of Short Interfering RNA
Authors: Soldan Samantha S. , Plassmeyer Matthew L. , Matukonis Meghan K. , González-Scarano Francisco
Published: December 2004

Through a process known as RNA interference (RNAi), double-stranded short interfering RNAs (siRNAs) silence gene expression in a sequence-specific manner. Recently, several viral proteins, including the nonstructural protein NSs of tomato spotted wilt virus (a plant-infecting bunyavirus), the interferon antagonist protein NS1 of influenza virus, and the E3L protein of vaccinia virus, have been shown to function as suppressors of RNAi, presumably as a counterdefense against cellular mechanisms that decrease viral production. La Crosse virus (LACV), a member of the California serogroup of orthobunyaviruses, has a trisegmented negative-stranded genome comprised of large (L), medium (M), and small (S) segments. To develop a strategy for segment-specific inhibition of transcription, we designed 13 synthetic siRNAs targeting specific RNA segments of the LACV genome that decreased LACV replication and antigen expression in mammalian (293T) and insect (C6/36) cells. Furthermore, NSs, a LACV nonstructural protein, markedly inhibited RNAi directed both against an LACV M segment construct and against a host gene (glyeraldehyde-3-phosphate dehydrogenase), suggesting a possible role for this viral protein in the suppression of RNA silencing. Segment-specific siRNAs will be useful as a tool to analyze LACV transcription and replication and to obtain recombinant viruses. Additionally, NSs will help us to identify molecular pathways involved in RNAi and further define its role in the innate immune system.
Human Endothelial Cells Enhance Human Immunodeficiency Virus Type 1 Replication in CD4+T Cells in a Nef-Dependent Manner In Vitro and In Vivo
Authors: Choi Jaehyuk , Walker Jason , Boichuk Sergei , Kirkiles-Smith Nancy , Torpey Nicholas , Pober Jordan S. , Alexander Louis
Published: December 2004

Infected CD4+T cells are the primary sites of human immunodeficiency virus type 1 (HIV-1) replication in vivo. However, signals from professional antigen-presenting cells (APCs), such as dendritic cells and macrophages, greatly enhance HIV-1 replication in T cells. Here, we report that in cocultures, vascular endothelial cells (ECs), which in humans can also serve as APCs, can enhance HIV-1 production of both CCR5- and CXCR4-utilizing strains approximately 50,000-fold. The observed HIV-1 replication enhancement conferred by ECs occurred only in memory CD4+T cells, required expression of major histocompatibility complex class II (MHC-II) molecules by the ECs, and could not be conferred by fixed ECs, all of which are consistent with a requirement for EC-mediated T-cell activation via T-cell receptor (TCR) signaling. Deletion ofnef(Nef−) decreased HIV-1 production by approximately 100-fold in T cells cocultured with ECs but had no effect on virus production in T cells cocultured with professional APCs or fibroblasts induced to express MHC-II. Human ECs do not express B7 costimulators, but Nef−replication in CD4+-T-cell and EC cocultures could not be rescued by anti-CD28 antibody. ECs act intransto enhance wild-type but not Nef−replication and facilitate enhanced wild-type replication in naïve T cells when added to T-cell or B-lymphoblastoid cell cocultures, suggesting that ECs also provide a TCR-independent signal to infected T cells. Consistent with these in vitro observations, wild-type HIV-1 replicated 30- to 50-fold more than Nef−in human T cells infiltrating allogeneic human skin grafts on human huPBL-SCID/bg mice, an in vivo model of T-cell activation by ECs. Our studies suggest that ECs, which line the entire cardiovascular system and are, per force, in frequent contact with memory CD4+T cells, provide signals to HIV-1-infected CD4+T cells to greatly enhance HIV-1 production in a Nef-dependent manner, a mechanism that could contribute to the development of AIDS.
Comprehensive Analysis of Human Endogenous Retrovirus Transcriptional Activity in Human Tissues with a Retrovirus-Specific Microarray
Authors: Seifarth Wolfgang , Frank Oliver , Zeilfelder Udo , Spiess Birgit , Greenwood Alex D. , Hehlmann Rüdiger , Leib-Mösch Christine
Published: December 2004

Retrovirus-like
sequences account for 8 to 9% of the human genome. Among these
sequences, about 8,000
pol
-containing proviral elements have
been identified to date. As part of our ongoing search for active and
possibly disease-relevant human endogenous retroviruses (HERVs), we
have recently developed an oligonucleotide-based microarray. The assay
allows for both the detection and the identification of most known
retroviral reverse transcriptase (RT)-related nucleic acids in
biological samples. In the present study, we have investigated the
transcriptional activity of representative members of 20 HERV families
in 19 different normal human tissues. Qualitative evaluation of chip
hybridization signals and quantitative analysis by real-time RT-PCR
revealed distinct HERV activity in the human tissues under
investigation, suggesting that HERV elements are active in human cells
in a tissue-specific manner. Most active members of HERV families were
found in mRNA prepared from skin, thyroid gland, placenta, and tissues
of reproductive organs. In contrast, only few active HERVs were
detectable in muscle cells. Human tissues that lack HERV transcription
could not be found, confirming that human endogenous retroviruses are
permanent components of the human transcriptome. Distinct activity
patterns may reflect the characteristics of the regulatory machinery in
these cells, e.g., cell type-dependent occurrence of transcriptional
regulatory
factors.
Kissing-Loop Interaction in the 3′ End of the Hepatitis C Virus Genome Essential for RNA Replication
Authors: Friebe Peter , Boudet Julien , Simorre Jean-Pierre , Bartenschlager Ralf
Published: December 2004

The hepatitis C virus (HCV) is a positive-strand RNA virus belonging to the
Flaviviridae
. Its genome carries at either end highly conserved nontranslated regions (NTRs) containing
cis
-acting RNA elements that are crucial for replication. In this study, we identified a novel RNA element within the NS5B coding sequence that is indispensable for replication. By using secondary structure prediction and nuclear magnetic resonance spectroscopy, we found that this RNA element, designated 5BSL3.2 by analogy to a recent report (S. You, D. D. Stump, A. D. Branch, and C. M. Rice, J. Virol.
78:
1352-1366, 2004), consists of an 8-bp lower and a 6-bp upper stem, an 8-nucleotide-long bulge, and a 12-nucleotide-long upper loop. Mutational disruption of 5BSL3.2 structure blocked RNA replication, which could be restored when an intact copy of this RNA element was inserted into the 3′ NTR. By using this replicon design, we mapped the elements in 5BSL3.2 that are critical for RNA replication. Most importantly, we discovered a nucleotide sequence complementarity between the upper loop of this RNA element and the loop region of stem-loop 2 in the 3′ NTR. Mismatches introduced into the loops inhibited RNA replication, which could be rescued when complementarity was restored. These data provide strong evidence for a pseudoknot structure at the 3′ end of the HCV genome that is essential for replication.
Focal Distribution of Baculovirus IE1 Triggered by Its Binding to the
hr
DNA Elements
Authors: Nagamine Toshihiro , Kawasaki Yu , Iizuka Tetsutaro , Matsumoto Shogo
Published: December 2004

In BmN cells infected with the baculovirus
Bombyx mori
nucleopolyhedrovirus (BmNPV), IE1, a principal transcriptional activator, localizes to sites of viral DNA replication. IE1 initially displays focal distribution in BmNPV-infected cells prior to DNA synthesis, whereas the protein expressed by transfection with the
ie1
gene is distributed throughout the nucleoplasm instead of localized to discrete subnuclear structures. To identify the inducer of focus formation for IE1, we conducted transfection experiments with an
IE1-GFP
construct and found that cotransfection with genomic DNA fragments bearing the homologous region (
hr
) sequences caused the formation of IE1-green fluorescent protein (GFP) foci. The transfection of insect cells with a single plasmid containing exclusively the
hr
3 sequence and the
IE1-GFP
gene was sufficient to form IE1-GFP foci. These results suggest that
hr
elements are a primary determinant of the focal distribution of IE1. An analysis of a series of
hr
3 deletion mutants showed that a single copy of the direct repeat could induce the formation of IE1 foci. Targeted mutagenesis within the
hr
-binding domain of IE1-GFP caused impairment of the
hr
-dependent IE1 localization, suggesting that binding of IE1 to the
hr
elements is essential for the onset of IE1 focus formation. The observation of BmNPV IE1 foci in non-BmNPV-susceptible cells suggests that no species-specific factors are required for
hr
-dependent IE1 focus formation.
CD8+T-Cell-Mediated Cross-Clade Protection in the Genital Tract following Intranasal Immunization with Inactivated Human Immunodeficiency Virus Antigen Plus CpG Oligodeoxynucleotides
Authors: Jiang Janina Q. , Patrick Amy , Moss Ronald B. , Rosenthal Kenneth L.
Published: December 2004

Human immunodeficiency virus (HIV) is a mucosally transmitted infection that rapidly targets and depletes CD4+T cells in mucosal tissues and establishes a major reservoir for viral persistence in gut-associated lymphoid tissues. Therefore, vaccines designed to prevent HIV infections must induce potent and durable mucosal immune responses, especially in the genital tract. Here we investigated whether intranasal (i.n.) immunization with inactivated gp120-depleted HIV-1 antigen (Ag) plus CpG oligodeoxynucleotide (ODN) as an adjuvant induced local immune responses in the genital tract and cross-clade protection against intravaginal (IVAG) challenge. Lymphocytes isolated from the iliac lymph nodes (ILNs) and genital tracts of female mice i.n. immunized with HIV-1 Ag plus CpG showed significant HIV-specific proliferation and produced significantly higher levels of gamma interferon (IFN-γ) and β-chemokines than mice immunized with HIV-1 Ag alone or mixed with non-CpG ODN. CD8+lymphocytes were dramatically increased in the genital tracts of mice immunized with HIV-1 Ag plus CpG, and protection following IVAG challenge with recombinant vaccinia viruses (rVVs) expressing HIV-1 gag was shown to be CD8 dependent. Finally, cross-clade protection was observed between clades A, C, and G but not B following IVAG challenge with rVVs expressing HIV-1gagfrom different clades. These studies provide evidence that mucosal (i.n.) immunization induced strong local T-cell-mediated immune responses in the genital tract and cross-clade protection against IVAG challenge.
Defective Interfering RNA Hinders the Activity of a Tombusvirus-Encoded Posttranscriptional Gene Silencing Suppressor
Authors: Havelda Zoltán , Hornyik Csaba , Válóczi Anna , Burgyán József
Published: December 2004

Defective interfering (DI) RNAs are subviral replicons originating from the viral genome and are associated with many plant RNA viruses and nearly all animal RNA viruses. The presence of DI RNAs in tombusvirus-infected plants reduces the accumulation of helper virus RNA and results in the development of attenuated symptoms similar to those caused by tombusviruses defective in p19, the posttranscriptional gene silencing (PTGS) suppressor. In situ analysis of infected plants containing DI RNAs revealed that the extent of virus infection was spatially restricted as was found for p19-defective tombusvirus. Previously, p19 was shown to suppress PTGS by sequestering the small interfering RNAs (siRNAs), which act as the specificity determinant for PTGS. Our results demonstrate that DI RNAs dramatically elevate the level of virus-specific siRNAs in viral infections, resulting in the saturation of p19 and the accumulation of unbound siRNAs. Moreover, we showed that, at low temperature, where PTGS is inhibited, DI RNAs are not able to efficiently interfere with virus accumulation and protect the plants. These data show that the activation of PTGS plays a pivotal role in DI RNA-mediated interference. Our data also support a role for 21-nucleotide siRNAs in PTGS signaling.
Conditional Cytomegalovirus Replication In Vitro and In Vivo
Authors: Rupp Brigitte , Ruzsics Zsolt , Sacher Torsten , Koszinowski Ulrich H.
Published: December 2004

We have established a conditional gene expression system for cytomegalovirus which allows regulation of genes independently from the viral replication program. Due to the combination of all elements required for regulated expression in the same viral genome, conditional viruses can be studied in different cell lines in vitro and in the natural host in vivo. The combination of a self-sufficient tetracycline-regulated expression cassette and Flp recombinase-mediated insertion into the viral genome allowed fast construction of recombinant murine cytomegaloviruses carrying different conditional genes. The regulation of two reporter genes, the essential viral M50 gene and a dominant-negative mutant gene (
m48.2
) encoding the small capsid protein, was analyzed in more detail. In vitro, viral growth was regulated by the conditional expression of M50 by 3 orders of magnitude and up to a millionfold when the dominant-negative small capsid protein mutant was used. In vivo, viral growth of the dominant-negative mutant was reduced to detection limits in response to the presence of doxycycline in the organs of mice. We believe that this conditional expression system is applicable to genetic studies of large DNA viruses in general.
The Poxviral RING Protein p28 Is a Ubiquitin Ligase That Targets Ubiquitin to Viral Replication Factories
Authors: Nerenberg Bianca T. Hovey , Taylor John , Bartee Eric , Gouveia Kristine , Barry Michele , Früh Klaus
Published: December 2004

The poxviral RING protein p28 is a virulence factor whose molecular function is unknown. Many cellular RING-containing proteins act as ubiquitin ligases (RING-E3s) connecting selected substrate proteins to the ubiquitination machinery. Here we demonstrate that vaccinia virus p28 and its homologue in myxoma virus, M143R, can mediate the formation of polyubiquitin conjugates, while RING mutants of both p28 and M143R cannot. Furthermore, p28 is ubiquitinated in vivo and ubiquitin colocalizes with p28 to virus factories independently of an intact RING domain. These results implicate the ubiquitin system in poxviral virulence.
Long-Term Productive Human Immunodeficiency Virus Infection of CD1a-Sorted Myeloid Dendritic Cells
Authors: Popov Sergei , Chenine Agnès-Laurence , Gruber Andreas , Li Pei-Lin , Ruprecht Ruth M.
Published: December 2004

Myeloid, CD1a-sorted dendritic cells (MDC) productively replicated human immunodeficiency virus strains encoding envelope genes of either primary X4R5 or R5 strains for up to 45 days. Cell-free supernatant collected from long-term infected MDC, which had been exposed to an X4R5 virus 45 days earlier, was still infectious when placed over activated T cells. These data imply that DC can act as a persistent reservoir of infectious virus.
Hepatocyte Growth Factor Receptor Is a Coreceptor for Adeno-Associated Virus Type 2 Infection
Authors: Kashiwakura Yuji , Tamayose Kenji , Iwabuchi Kazuhisa , Hirai Yukihiko , Shimada Takashi , Matsumoto Kunio , Nakamura Toshikazu , Watanabe Masami , Oshimi Kazuo , Daida Hiroyuki
Published: December 2004

After the first attachment of virus to the cell surface through a primary receptor, efficient entry of virus requires the presence of a coreceptor. For adeno-associated virus type 2 (AAV2) infection, heparan sulfate proteoglycan is supposed as the primary receptor, and αvβ5 integrin and FGFR1 are reported to act as coreceptors. In this study, we were able to demonstrate that hepatocyte growth factor receptor, c-Met, is also a coreceptor for AAV2 infection. AAV2-mediated transgene analyses revealed that c-Met expression significantly up-regulated transgene expression without increasing AAV2 cell binding. Moreover, a viral overlay assay elucidated the physical interaction between AAV2 and the β subunit of c-Met. These data suggest that c-Met plays the role of coreceptor for AAV2 infection by facilitating AAV2 internalization into the cytoplasm.
Comparative Immunogenicity of Human Immunodeficiency Virus Particles and Corresponding Polypeptides in a DNA Vaccine
Authors: Akahata Wataru , Yang Zhi-yong , Nabel Gary J.
Published: December 2004

The immunogenicity of a plasmid DNA expression vector encoding both Gag and envelope (Env), which produced human immunodeficiency virus (HIV) type 1 virus-like particles (VLP), was compared to vectors expressing Gag and Env individually, which presented the same gene products as polypeptides. Vaccination with plasmids that generated VLP showed cellular immunity comparable to that of Gag and cell-mediated or humoral responses similar to those of Env as immunization with separate vectors. These data suggest that DNA vaccines encoding separated HIV polypeptides generate immune responses similar to those generated by viral particles.
Implementation of team training in medical education in Denmark
Authors: Østergaard H T , Østergaard D , Lippert A
Published: December 2004

In the field of medicine, team training aiming at improving team skills such as leadership, communication, co-operation, and followership at the individual and the team level seems to reduce risk of serious events and therefore increase patient safety. The preferred educational method for this type of training is simulation. Team training is not, however, used routinely in the hospital. In this paper, we describe a framework for the development of a team training course based on need assessment, learning objectives, educational methods including full-scale simulation and evaluations strategies. The use of this framework is illustrated by the present multiprofessional team training in advanced cardiac life support, trauma team training and neonatal resuscitation in Denmark. The challenges of addressing all aspects of team skills, the education of the facilitators, and establishment of evaluation strategies to document the effect of the different types of training on patient safety are discussed.
QUBITS AND QUANTUM SPACES
Authors: ZIZZI P. A.
Published: December 2004

We consider the quantum computational process as viewed by an insider observer: this is equivalent to an isomorphism between the quantum computer and a quantum space, namely the fuzzy sphere. The result is the formulation of a reversible quantum measurement scheme, with no hidden information.
NETWORK COMMUNICATIONS: Lymphotoxins, LIGHT, and TNF
Authors: Ware Carl F.
Published: December 2004

▪ Abstract  Lymphotoxins (LT) provide essential communication links between lymphocytes and the surrounding stromal and parenchymal cells and together with the two related cytokines, tumor necrosis factor (TNF) and LIGHT (LT-related inducible ligand that competes for glycoprotein D binding to herpesvirus entry mediator on T cells), form an integrated signaling network necessary for efficient innate and adaptive immune responses. Recent studies have identified signaling pathways that regulate several genes, including chemokines and interferons, which participate in the development and function of microenvironments in lymphoid tissue and host defense. Disruption of the LT/TNF/LIGHT network alleviates inflammation in certain autoimmune disease models, but decreases resistance to selected pathogens. Pharmacological disruption of this network in human autoimmune diseases such as rheumatoid arthritis alleviates inflammation in a significant number of patients, but not in other diseases, a finding that challenges our molecular paradigms of autoimmunity and perhaps will reveal novel roles for this network in pathogenesis.
Intracellular pH homeostasis in cultured human placental syncytiotrophoblast cells: recovery from acidification
Authors: Cowley Elizabeth A. , Sellers Mary C. , Illsley Nicholas P.
Published: December 2004

Resting or basal intracellular pH (pHi) measured in cultured human syncytiotrophoblast cells was 7.26 ± 0.04 (without HCO3−) or 7.24 ± 0.03 (with HCO3−). Ion substitution and inhibitor experiments were performed to determine whether common H+-transporting species were operating to maintain basal pHi. Removal of extracellular Na+ or Cl− or addition of amiloride or dihydro-4,4′-diisothiocyanatostilbene-2,2′-disulfonate (H2DIDS) had no effect. Acidification with the K+/H+ exchanger nigericin reduced pHi to 6.25 ± 0.15 (without HCO3−) or 6.53 ± 0.10 (with HCO3−). In the presence of extracellular Na+, recovery to basal pHi was prompt and occurred at similar rates in the absence and presence of HCO3−. Ion substitution and inhibition experiments were also used to identify the species mediating the return to basal pHi after acidification. Recovery was inhibited by removal of Na+ or addition of amiloride, whereas removal of Cl− and addition of H2DIDS were ineffective. Addition of the Na+/H+ exchanger monensin to cells that had returned to basal pHi elicited a further increase in pHi to 7.48 ± 0.07. Analysis of recovery data showed that there was a progressive decrease in ΔpH per minute as pHi approached the basal level, despite the continued presence of a driving force for H+ extrusion. These data show that in cultured syncytial cells, in the absence of perturbation, basal pHi is preserved despite the absence of active, mediated pH maintenance. They also demonstrate that an Na+/H+ antiporter acts to defend the cells against acidification and that it is the sole transporter necessary for recovery from an intracellular acid load.
Activation of the JAK/STAT pathway in vascular smooth muscle by serotonin
Authors: Banes Amy K. L. , Shaw Seán M. , Tawfik Amany , Patel Bela P. , Ogbi Safia , Fulton David , Marrero Mario B.
Published: December 2004

Serotonin (5-hydroxytryptamine, 5-HT) is a vasoconstrictor and mitogen whose levels are elevated in diabetes. Previous studies have shown the presence of 5-HT2A, 5-HT2B, and 5-HT1B receptors in vascular smooth muscle cells (VSMCs). There are currently no data regarding 5-HT2B and 5-HT1B receptor activation of the JAK/STAT pathway in VSMCs and resultant potential alterations in 5-HT signaling in diabetes. Therefore, we tested the hypothesis that 5-HT differentially activates the JAK/STAT pathway in VSMCs under conditions of normal (5 mM) and high (25 mM) glucose. Treatment of rat VSMCs with 5-HT (10−6 M) resulted in time-dependent activation (∼2-fold) of JAK2, JAK1, and STAT1, but not STAT3 (maximal at 5 min, returned to baseline by 30 min). The 5-HT2B receptor agonist BW723C86 and the 5-HT1B receptor agonist CGS12066A (10−9–10−5 M, 5-min stimulation) did not activate the JAK/STAT pathway. Treatment with the 5-HT2A receptor antagonist ketanserin (10 nM) inhibited JAK2 activation by 5-HT. Treatment of streptozotocin-induced diabetic rats with ketanserin (5 mg·kg−1·day−1) reduced activation of JAK2 and STAT1 but not STAT3 in endothelium-denuded thoracic aorta in vivo. 5-HT (10−6 M) treatment resulted in increased cell proliferation and increased DNA synthesis, which were inhibited by the JAK2 inhibitor AG490. Further studies with apocynin, diphenyleneiodonium chloride, catalase, and virally transfected superoxide dismutase had no effect at either glucose concentration on activation of the JAK/STAT pathway by 5-HT. Therefore, we conclude that 5-HT activates JAK2, JAK1, and STAT1 via the 5-HT2A receptors in a reactive oxygen species-independent manner under both normal and high glucose conditions.
Distinct role of hydrodynamic shear in leukocyte-facilitated tumor cell extravasation
Authors: Slattery Margaret J. , Liang Shile , Dong Cheng
Published: December 2004

Previously, we found polymorphonuclear neutrophils (PMNs) increased melanoma cell extravasation under flow conditions ( Intl J Cancer 106: 713–722, 2003). In this study, we characterized the effect of hydrodynamic shear on PMN-facilitated melanoma extravasation using a novel flow-migration assay. The effect of shear stress and shear rate on PMN-facilitated melanoma extravasation was studied by increasing the medium viscosity with dextran to increase shear stress independently of shear rate. Under fixed shear rate conditions, melanoma cell extravasation did not change significantly. In contrast, the extravasation level increased at a fixed shear stress but with a decreasing shear rate. PMN-melanoma aggregation and adhesion to the endothelium via β2-integrin/intracellular adhesion molecule-1 (ICAM-1) interactions were also studied. Lymphocyte function-associated molecule-1 (LFA-1; CD11a/CD18) influenced the capture phase of PMN binding to both melanoma cells and the endothelium, whereas Mac-1 (CD11b/CD18) affected prolonged PMN-melanoma aggregation. Blockage of E-selectin or ICAM-1 on the endothelium or ICAM-1 on the melanoma surface reduced PMN-facilitated melanoma extravasation. We have found PMN-melanoma adhesion is correlated with the inverse of shear rate, whereas the PMN-endothelial adhesion correlated with shear stress. Interleukin-8 (IL-8) also influenced PMN-melanoma cell adhesion. Functional blocking of the PMN IL-8 receptors, CXCR1 and CXCR2, decreased the level of Mac-1 upregulation on PMNs while in contact with melanoma cells and reduced melanoma extravasation. We have found PMN-facilitated melanoma adhesion to be a complex multistep process that is regulated by both microfluid mechanics and biology.
Transgenic prolactin−/− mice: effect of trauma-hemorrhage on splenocyte functions
Authors: Matsutani Takeshi , Samy T. S. Anantha , Rue Loring W. , Bland Kirby I. , Chaudry Irshad H.
Published: December 2004

Prolactin (PRL) is involved in the regulation of immune functions under normal and pathological conditions. Trauma-hemorrhage (T-H) produces profound immunosuppression in male mice but not in proestrus female mice. Administration of PRL in males after T-H, however, restores immune functions. In this study, PRL+/+ and transgenic (PRL−/−) male and female mice were used to assess immune suppression after T-H and to determine the reasons for the hormone's beneficial effect. In vitro lymphoproliferation assay with Nb2 cells showed complete absence of PRL in the circulation of the transgenic PRL−/− mice of both sexes, whereas very high levels of the hormone were detected in the wild-type PRL+/+ mice of both sexes. Moreover, T-H resulted in the appearance of significant levels of the hormone in circulation, but only in PRL+/+ mice. Splenocyte proliferation in male PRL−/− mice was significantly lower than in PRL+/+ mice after T-H. Marginal differences between PRL+/+ and PRL−/− mice were observed in the release of IL-2 and IFN-γ by splenocytes, while the release of IL-10 was significantly higher in PRL−/− than in PRL+/+ mice. A significant observation of our study is the release of a ∼25-kDa protein in the concanavalin A-stimulated splenocytes of male PRL+/+ and PRL−/− mice that was active in the in vitro lymphoproliferation assay with Nb2 cells. It is unlikely that this protein is PRL because it is also present in the splenocyte extracts of PRL−/− transgenic mice. Nonetheless, because control of lymphoid cell proliferation is considered one of the characteristics of the immune system, the local release of this protein may be significant in the differences observed in splenocyte cytokine release after T-H in wild-type as well as transgenic mice.
Administration of ANG II induces iron deposition and upregulation of TGF-β1 mRNA in the rat liver
Authors: Ishizaka Nobukazu , Saito Kan , Noiri Eisei , Sata Masataka , Ikeda Hitoshi , Ohno Akihiko , Ando Jiro , Mori Ichiro , Ohno Minoru , Nagai Ryozo
Published: December 2004

We previously found that ANG II infusion into rats causes iron deposition in the kidney and heart, which may have a role in the regulation of profibrotic gene expression and tissue fibrosis. In the present study, we have investigated whether ANG II can also induce iron accumulation in the liver. Prussian blue staining detected frequent iron deposition in the interstitium of the liver of rats treated with pressor dose ANG II for 7 days, whereas iron deposition was absent in the livers of control rats. Immunohistochemical and histological analyses showed that some iron-positive nonparenchymal cells were positive for ferritin and heme oxygenase-1 (HO-1) protein and TGF-β1 mRNA and were judged to be monocytes/macrophages. It was shown that ANG II infusion caused about a fourfold increase in ferritin and HO-1 protein expression by Western blot analysis and about a twofold increase in TGF-β1 mRNA expression by Northern blot analysis, which were both suppressed by treating ANG II-infused rats with losartan and deferoxamine. In addition, mild interstitial fibrosis was observed in the liver of rats that had been treated with pressor dose ANG II for 7 days or with nonpressor dose ANG II for 30 days, the latter of which also caused loss of hepatocytes and intrahepatic hemorrhage in the liver. Taken together, our data suggest that ANG II infusion induces aberrant iron homeostasis in the liver, which may have a role in the ANG II-induced upregulation of profibrotic gene expression in the liver.
Responses of Irregularly Discharging Chinchilla Semicircular Canal Vestibular-Nerve Afferents During High-Frequency Head Rotations
Authors: Hullar Timothy E. , Della Santina Charles C. , Hirvonen Timo , Lasker David M. , Carey John P. , Minor Lloyd B.
Published: December 2004

Mammalian vestibular-nerve afferents innervating the semicircular canals have been divided into groups according to their discharge regularity, gain at 2-Hz rotational stimulation, and morphology. Low-gain irregular afferents terminate in calyx endings in the central crista, high-gain irregular afferents synapse more peripherally in dimorphic (bouton and calyx) endings, and regular afferents terminate in the peripheral zone as bouton-only and dimorphic endings. The response dynamics of these three groups have been described only up to 4 Hz in previous studies. Reported here are responses of chinchilla semicircular canal vestibular-nerve afferents to rotational stimuli at frequencies up to 16 Hz. The sensitivity of all afferents increased with increasing frequency with the sensitivity of low-gain irregular afferents increasing the most and matching the high-gain irregular afferents at 16 Hz. All afferents increased their phase lead with respect to stimulus velocity at higher frequencies with the highest leads in low-gain irregular afferents and the lowest in regular afferents. No attenuation of sensitivity or shift in phase consistent with the presence of a high-frequency pole over the range tested was noted. Responses were best fit with a torsion-pendulum model combined with a lead operator (τHF1s + 1)(τHF2s + 1). The discharge regularity of individual afferents was correlated to the value of each afferent's lead operator time constants. These findings suggest that low-gain irregular afferents are well suited for encoding the onset of rapid head movements, a property that would be advantageous for initiation of reflexes with short latency such as the vestibulo-ocular reflex.
Public management in developing countries: some notes on Eritrea
Authors: Soeters Joseph L. , Tessema Mussie Teclemichael
Published: December 2004

A system of adequately performing public bureaucracies is a basic requirement for developing countries to progress and prosper. However, public management in developing countries is often threatened by politicization and ineffective human resource management policies. In this article, we analyse public management in Eritrea, one of the world’s poorest countries that gained independence in the early 1990s. In this analysis, we use general (western) theoretical frames of reference, including pre-modern, weberian and new public management lines of thinking. It will show that, in current Eritrea, all known styles of public management concur and collide and that this situation is related to the cultural, educational and political background of the various population groups that strive for job opportunities in the public sector’s strategic apex. This collision of styles may lead to frustration and ineffectiveness among the people involved. Only a managerial policy stressing practical wisdom and intelligence may satisfy all the groups of people engaged in Eritrea’s public management, in fact in all developing countries’ public organizations.
Alternative service delivery — responding to global pressures
Authors: Fyfe Toby
Published: December 2004

The new integrated global environment has resulted in a paradigm shift from the nation-state to the international community as a driver of change, an unprecedented degree and speed of change, the replacement of single policy issues with cross-cutting ones and a demand by citizens for improved service delivery. In response, governments are creating alternative service delivery (ASD) arrangements. Jurisdictions using ASD can be placed on a continuum of organizational change. There are slow starters in which all service delivery is state-owned, operated and designed around government needs. There are structural changers that pursue a formulaic approach to organizational change. Finally, there are transformational changers that take a principles-based case-by-case approach to organizational renewal, ensuring that each initiative responds to the particular challenge of the nation and its entities. In Canada, the Policy on Alternative Service Delivery provides guidance for jurisdictions contemplating organizational change with the Public Interest Test.

This article will examine the role that organizational change plays in countries that are implementing major governmental change initiatives. It will review the influence of an increasingly integrated global environment on government change and examine how ASD can act as an organizational response to this environment. It will look at the governance issues that countries face when implementing ASD and propose a typology for classifying countries as change agents. Finally, it will reference a principles-based approach for implementing organizational change through ASD that is being implemented in Canada.
Fight for equality in a transforming China: community development in urbanization
Authors: Songyan Chu
Published: December 2004

Social justice is an important tenet of China’s process of reform and openness. During its current rapid economic transition, urbanization is creating new opportunities and new challenges for maintaining social justice based on individual rights. Community-building has become an important priority during urbanization in China’s transition. Both the theoretical literature and the activities of citizens illustrate the efforts made by both urban and rural citizens. In order to maintain social justice during the transition, China must break down the dual-citizenship system established by the hukou system of division between urban and rural citizens. Citizens in communities should participate in public policy-making processes without such classification. Current activities across China demonstrate that efforts toward such equality have been initiated.
Economic and social trends in Latin America: the bases for social discontent
Authors: Grynspan Rebeca
Published: December 2004

The great economic growth achieved in Latin America during the 1990s was accompanied by negative characteristics from unemployment to volatility. Moreover, the ‘lost half-decade’ of 1997—2002 witnessed an increase in poverty and growing inequality. The promised accelerated growth, low unemployment, improved income distribution and reduction of poverty were far from achieved despite the liberalization that led to higher exports and direct foreign investment. In the aftermath, a space has opened for the broad, creative review of the region’s development agenda, particularly in light of the Millennium Development Goals. If Latin America is to meet these goals, it must not only achieve economic growth and recover external markets but also complement these with a dynamic development that is integrating, inclusive, equitable, democratic and participatory.
Violent Lives: A Lifestyle Model Linking Exposure to Violence to Juvenile Violent Offending
Authors: Nofziger Stacey , Kurtz Don
Published: December 2004

Studies examining the consequences of juvenile exposure to violence focus largely on psychological outcomes and often ignore the ways in which exposure is associated with deviant peers and juvenile offending. Using data from the National Survey of Adolescents (NSA), a nationally representative sample of juveniles between the ages of 12 and 17, we examine the relationship between various types of exposure to violence and violent offending. Based on Hindelang, Gottfredson, and Garofalo’s Lifestyle model of victimization (1978), the authors argue that exposure to violence is indicative of a lifestyle of violence. Such a lifestyle makes juveniles susceptible to victimization, witnessing violence, and association with violent peers. The findings demonstrate that these indicators of violent lifestyles in turn act as a risk factor for violent offending.
Web use and peer interconnectivity metrics for academic web sites
Authors: Thelwall Mike
Published: December 2004

This paper introduces two new web link count metrics to complement the existing Web Impact Factor. The first is provisionally cast as an indicator of the average degree of online informal scholarly communication and information use by the academics in a given university. The second has a similar construction but focuses on the degree of web interconnection in terms of both inlinks and outlinks. The latter metric is based upon a more elaborate mechanism than raw link counts: totalling the minimum number of links between universities over all distinct pairs in the chosen set that include the given institution. Statistical tests give evidence that the results of both correlate with institutional research productivity in the UK, providing preliminary support for their continued development. Further research is needed into causes of linking in order to allow more meaningful interpretations of their values to be made.
The Baltimore City Drug Treatment Court
Authors: Gottfredson Denise C. , Kearley Brook W. , Najaka Stacy S. , Rocha Carlos M.
Published: December 2004

This study reports results from interviews with 157 research participants who were interviewed 3 years after randomization into treatment and control conditions in the evaluation of the Baltimore City Drug Treatment Court. The interviews asked about crime, substance use, welfare, employment, education, mental and physical health, and family and social relationships. Program participants reported less crime and substance use than did controls. Few differences between groups were observed on other outcomes, although treatment cases were less likely than controls to be on the welfare rolls at the time of the interview. Effects differed substantially according to the originating court.
Does Funding for HIV and Sexually Transmitted Disease Prevention Matter?
Authors: Chesson Harrell W. , Harrison Paul , Scotton Carol R. , Varghese Beena
Published: December 2004

Since the onset of the AIDS epidemic, the Centers for Disease Control and Prevention (CDC) has allocated several billion dollars for the prevention of HIV and other sexually transmitted diseases (STDs) in the United States. Using state-level data from 1981 to 1998, the authors found that greater amounts of prevention funding in a given year are associated with reductions in reported gonorrhea incidence rates in subsequent years. The authors conclude that funding for STD and HIV prevention, on the whole, appears to have a discernable impact on the incidence of STDs.
Measured gas emissions from four landfills in South Africa and some implications for landfill design and methane recovery in semi-arid climates
Authors: Fourie A. B. , Morris J. W. F.
Published: December 2004

The magnitude of annual global emissions of methane from municipal solid waste landfills without landfill gas control systems implies that these landfills are significant contributors to the atmospheric load of greenhouse gases. There have been a number of field studies undertaken internationally to measure actual fluxes of methane and carbon dioxide from landfills, with a view to corroborating modelled predictions of the contribution of landfills to the global greenhouse gas budget. The vast majority of these studies have been undertaken in more temperate climates and in developed countries. This paper reports a study of landfill gas emissions from four large landfills located in the semi-arid interior of South Africa. A static accumulation chamber was used and measurements were made at each site over a period of two to three days. The results were analysed by three different methods, all of them leading to the same general conclusion that landfill gas emission rates were lower than expected. A common conclusion based on results from all four sites was that capping of landfills in semi-arid climates with low permeability covers would probably significantly retard the already low rate of waste degradation and thus gas generation. While this may be regarded as advantageous in the short term, it cannot be relied upon in perpetuity as clayey landfill covers will inevitably desiccate and crack in a semi-arid environment. In addition, reasonable after-care periods for such landfills are likely to extend well beyond the currently stipulated 30-year period, and efforts to encourage energy recovery from landfills may be hampered because gas generation rates decrease as the waste dries out under conditions of minimal recharge from precipitation. A landfill cover that allows small amounts of percolation of rainfall into the waste may therefore in fact be beneficial in semi-arid climates, although care would need to be taken to carefully regulate this infiltration.
The contribution of waste management to the reduction of greenhouse gas emissions with applications in the city of Bucharest
Authors: Sandulescu Elena
Published: December 2004

Waste management is a key process to protect the environment and conserve resources. The contribution of appropriate waste management measures to the reduction of greenhouse gas (GHG) emissions from the city of Bucharest was studied. An analysis of the distribution of waste flows into various treatment options was conducted using the material flows and stocks analysis (MFSA). An optimum scenario (i.e. municipal solid waste stream managed as: recycling of recoverable materials, 8%; incineration of combustibles, 60%; landfilling of non-combustibles, 32%) was modelled to represent the future waste management in Bucharest with regard to its relevance towards the potential for GHG reduction. The results indicate that it can contribute by 5.5% to the reduction of the total amount of GHGs emitted from Bucharest.
Biopurification of industrial waste gas from rubber regeneration
Authors: Sun Peishi , Yang Xianwan , Huang Ruohua , Bin Huang , Zheng Sunsheng , Wei Zaishan , Xu Xiaoyi , Lu Jilai , Sun Xing , Chen Liuxin
Published: December 2004

By using the biopurifying technology, the organic waste gas in low concentrations emitted from the rubber-regeneration process was purified in this research. The result of the 100-day continuous running test of the industrial test device indicated that the purification efficiency of toluene in the rubber-regeneration waste gas could be maintained at about 90% for a long period of time and the treated waste gas could meet the China National Emission Standard. The cost of waste gas biotreatment was about 0.12~0.14% of rubber-regeneration production value of the factory. The biopurifying technology of waste gas displayed its excellent technical advancement and economic rationale. The following industrialized device was run continuously and passed the examination and acceptance by the local EPA.