bluuebunny/crossref_metadata_2025 huggingface dataset:
Epidural Ropivacaine versus Epidural Morphine and the Catabolic Response to Colonic Surgery
Authors: Schricker Thomas , Wykes Linda , Eberhart Leopold , Lattermann Ralph , Carli Franco
Published: March 2004

Background

The authors examined the hypothesis that epidural administration of local anesthetic, in contrast to epidural analgesia with morphine, inhibits postoperative protein oxidation during administration of glucose.

Methods

Fourteen patients were randomly assigned to undergo a 6-h stable isotope infusion study (3 h fasted, 3 h feeding with 4 mg.kg(-1).min(-1) glucose) on the second day after colorectal surgery using epidural analgesia with either continuous ropivacaine or intermittent morphine. Protein synthesis, breakdown and oxidation, and glucose production were measured by L-[L-13C]leucine and [6,6-2H2]glucose. Substrate oxidation rates were determined by indirect calorimetry. Plasma concentrations of metabolic substrates and hormones were also measured.

Results

Whole body protein breakdown, oxidation, synthesis, and glucose production in the fasted state were similar between the two groups. Glucose administration decreased protein breakdown (P = 0.01), protein synthesis (P = 0.001), and glucose production (P = 0.001) to the same extent in both groups, whereas protein oxidation was not significantly affected. The type of epidural analgesia did not significantly influence the circulating concentrations of metabolic substrates and hormones in the fasted or in the fed state. Carbohydrate oxidation rate in the ropivacaine group was greater than in patients receiving morphine (P = 0.04), regardless of whether glucose was infused.

Conclusion

Epidural analgesia achieved with ropivacaine or morphine does not suppress the catabolic response to surgery, either under fasting conditions or in the presence of an energy supply.
Influence of Sensory and Proprioceptive Impairment on the Development of Phantom Limb Syndrome during Regional Anesthesia
Authors: Paqueron Xavier , Leguen Morgan , Gentili Marc E. , Riou Bruno , Coriat Pierre , Willer Jean Claude
Published: March 2004

Background

The relation between impairment of sensorimotor function and occurrence of phantom limb syndrome (PLS) during regional anesthesia has not been described. This study assessed the temporal relation between PLS and the progression of sensorimotor impairment during placement of a brachial plexus nerve block.

Methods

Fifty-two patients had their arm randomly placed either alongside their body (group A) or in 90 degrees abduction (group B) immediately after brachial plexus nerve block placement. Responses to pin prick, cold, heat, touch, proprioception, and voluntary movement were assessed every 5 min for 60 min. Meanwhile, patients described their perceptions of the size, shape, and position of their anesthetized limb.

Results

Phantom limb syndrome occurred 19 +/- 9 min after nerve block placement. Proprioception was impaired and abolished after 22 +/- 9 and 43 +/- 17 min, respectively (P < 0.05 vs. PLS onset). When PLS occurred, responses to pin prick, cold, heat, and proprioception were abolished in 96, 94, 87, and 4% of patients, respectively. Patients were more likely to feel their anesthetized limb in adduction and in abduction in groups A and B (P < 0.05 vs. group A), respectively. After PLS had become motionless, two stereotyped positions were identified: arm adduction, elbow flexion, hand over the abdomen (68% of group A patients) and arm abduction, elbow flexion, hand held close to the homolateral ear (48% of group B patients).

Conclusions

This study provides a better understanding of the determinants of PLS by showing that the final position of PLS is related both to the abolition of proprioception and the initial position of the anesthetized limb.
The index influenza A virus subtype H5N1 isolated from a human in 1997 differs in its receptor-binding properties from a virulent avian influenza virus
Authors: Iwatsuki-Horimoto Kiyoko , Kanazawa Rie , Sugii Shunji , Kawaoka Yoshihiro , Horimoto Taisuke
Published: March 2004

To gain insight into the events that occur when avian influenza viruses are transmitted to humans, the receptor-binding properties of the index H5N1 influenza virus isolated from a human in 1997 and the A/turkey/Ontario/7732/66 (H5N9) virus were compared, by using a haemadsorption assay. Cells expressing the haemagglutinin (HA) of the human isolate were adsorbed by both chicken red blood cells (RBCs) and human RBCs; those expressing the avian virus HA were only adsorbed by chicken RBCs. These results indicate that human and avian influenza virus H5 HAs differ in their recognition of sialyloligosaccharides on the RBCs of different animal species. Mutational analyses indicated that differences in both the oligosaccharide chains and in the amino acid sequences around the HA receptor-binding site were responsible for this difference in receptor binding. These data further support the concept that alteration in receptor recognition is important for replication of avian viruses in humans.
Host-dependent type 1 cytokine responses driven by inactivated viruses may fail to default in the absence of IL-12 or IFN-α/β
Authors: de Wit Marel C. , Horzinek Marian C. , Haagmans Bart L. , Schijns Virgil E. J. C.
Published: March 2004

Replicating viruses generally induce type 1 immune responses, with high interferon (IFN)-γlevels and antibodies of the IgG2a isotype. In the present study we demonstrate the intrinsic ability of non-replicating virions to induce comparable immune responses in the notable absence of any adjuvant. Injection of inactivated pseudorabies virus, an alphaherpesvirus, by various routes into mice resulted in the generation of T helper (Th) 1 type immune response. Co-delivery of inactivated pseudorabies herpesvirus (iPRV) with protein redirected IgG1-dominated tetanus toxoid-specific responses towards an IgG1/IgG2a balanced response. Also inactivated preparations of viruses from the paramyxo- (Newcastle disease virus), rhabdo- (rabies virus), corona- (infectious bronchitis virus) and reovirus (avian reovirus) families led to IgG2a antibody responses; however, the genetic background of the host did result in considerable variation. Because disrupted virions also induced type 1 immune responses, we conclude that structural elements of virions inherently contribute to IFN-γ-dependent isotype switching by inactivated viruses. Strikingly, immunizations in gene-disrupted mice showed that a functional IFN-α/β, IFN-γor interleukin (IL)-12 pathway was not required for the generation of a polarized Th1 type immune response initiated by inactivated virus particles. These findings have a bearing on the understanding of immune responsiveness to virus structures and the design of vaccines containing virus components.
A role for 3-O-sulfated heparan sulfate in cell fusion induced by herpes simplex virus type 1
Authors: Tiwari Vaibhav , Clement Christian , Duncan Michael B. , Chen Jinghua , Liu Jian , Shukla Deepak
Published: March 2004

Membrane fusion induced by herpes simplex virus (HSV) is required for both entry and cell-to-cell spread. It is mediated by the viral glycoprotein gB, gD, gH–gL and gD receptors. Although 3-O-sulfated heparan sulfate (3-OS HS) is a receptor for HSV-1 entry, the requirement for heparan sulfate in the fusion process has been ruled out. Here, it is demonstrated that cells expressing 3-OS HS, generated by d-glucosaminyl 3-O-sulfotransferase isoforms-3 and/or -5 (3-OST-3 and 3-OST-5), fused with cells expressing the four glycoproteins. The cell fusion observed exhibited similar requirements but was independent of protein receptors, HVEM or nectin-1. Additionally, removal of 3-OS HS from the cell surface by heparinase-I treatment and, in separate experiments, the presence of soluble 3-OST-3- and 3-OST-5-modified HS, significantly inhibited fusion. Taken together, these results indicate that 3-OS HS can play a crucial role in virus entry and cell fusion.
Polarized glycoprotein targeting affects the spread of measles virus in vitro and in vivo
Authors: Moll Markus , Pfeuffer Joanna , Klenk Hans-Dieter , Niewiesk Stefan , Maisner Andrea
Published: March 2004

We have shown previously that basolateral targeting of plasmid-encoded measles virus (MV) F and H protein is dependent on single tyrosine residues in the cytoplasmic tails of the glycoproteins and is essential for fusion activity in polarized epithelial cells. Here, we present data on the functional importance of polarized glycoprotein expression for the cytopathic properties of infectious MV in culture and for pathogenesis in vivo. By the introduction of single point mutations, we generated recombinant viruses in which the basolateral targeting signal of either one or both glycoproteins was destroyed (tyrosine mutants). As a consequence, the mutated glycoproteins were predominantly expressed on the apical membrane of polarized Madin–Darby canine kidney cells. In contrast to parental MV, none of these virus mutants was able to spread by syncytia formation in polarized cells showing that the presence of both MV glycoproteins at the basolateral cell surface is required for cell-to-cell fusion in vitro. Using cotton rats as an animal model that allows MV replication in the respiratory tract, we showed that basolateral glycoprotein targeting is also of importance for the spread of infection in vivo. Whereas parental MV was able to spread laterally within the respiratory epithelium and from there to cells in the underlying tissue, tyrosine mutants infected only single epithelial and very few subepithelial cells. These data strongly suggest that basolateral targeting of MV glycoproteins helps to overcome the epithelial barrier and thereby facilitates the systemic spread of MV infection in vivo.
Identification of a glycosylation site in the woodchuck hepatitis virus preS2 protein and its role in protein trafficking
Authors: Schildgen O. , Roggendorf M. , Lu M.
Published: March 2004

The middle surface antigen (M-sAg) of hepadnaviruses is one of three envelope proteins that share a common C-terminal S domain. M-sAg contains the preS2 domain in addition to the S region. The preS2 region of woodchuck hepatitis virus (WHV) contains a potential glycosylation site Asn-Gln-Thr at amino acid (aa) positions 3–5. In this study, we mutated this site by site-directed mutagenesis and confirmed that glycosylation occurs here. Inin vitrotranslation assays, the mutation Thr to Asn at aa 5 significantly impaired glycosylation of M-sAg. The mutated M-sAg formed abnormal clustered structures in transfected cells as determined by immunofluorescent staining. Confocal microscopic analysis showed that an enrichment of this glycosylation-deficient protein in the Golgi apparatus occurred, which is not typical for the wild-type protein. These results are consistent with earlier findings that incorrect glycosylation of viral proteins may interfere with virus assembly.
Proliferation and differentiation in isogenic populations of peripheral B cells activated by Epstein–Barr virus or T cell-derived mitogens
Authors: O'Nions Jenny , Allday Martin J.
Published: March 2004

Human B cells isolated from peripheral blood were activated and induced to proliferate by either Epstein–Barr virus (EBV) or the T cell-derived mitogens CD40 ligand (CD40L) plus interleukin (IL)-4. Although both populations initially proliferated as B-blasts, significant differences were revealed over a longer period. EBV infection resulted in continuously proliferating lymphoblastoid cell lines (LCLs), whereas most of the CD40L/IL-4-stimulated B cells had a finite proliferative lifespan of 3–4 weeks. Cell cycle analysis, trypan blue staining and Western blot analysis for cleavage of poly(ADP-ribose) polymerase (PARP) all demonstrated that the decrease in proliferation in CD40L/IL-4-stimulated B cells is not due to cell death. Instead, these cells arrest, accumulate in G0/G1and undergo alterations in cell surface marker expression, cellular morphology and immunoglobulin production, all consistent with plasmacytoid differentiation. In contrast, B cells infected with EBV continued to proliferate and retained a blast-like phenotype. Differences in both cytokine production and the expression of cell cycle regulators were identified between the two B-cell populations, which might contribute to the differentiation of the CD40L/IL-4-stimulated B cells and suggest potential mechanisms by which EBV may overcome this. The study has also identified a window of opportunity during which a comparison of isogenic populations of EBV- and mitogen-driven B blasts can be made.
Establishment of cell lines from the wasp Hyposoter didymator (Hym., Ichneumonidae) containing the symbiotic polydnavirus H. didymator ichnovirus
Authors: Rocher Janick , Ravallec Marc , Barry Patrick , Volkoff Anne-Nathalie , Ray Dominique , Devauchelle Gérard , Duonor-Cérutti Martine
Published: March 2004

Cell lines derived from polydnavirus-associated wasps should constitute a valuable tool for investigations of polydnavirus replication, but none is yet available. In this work, we describe the first cell lines, named Hd-AA, -AD, -BBA and -K, to have been established from the ichneumonid wasp Hyposoter didymator, associated with the polydnavirus H. didymator ichnovirus (HdIV). Southern blot analysis indicated that the viral DNA was present in all four cell lines and co-localized with high molecular mass DNA, probably the wasp chromosomes. Northern blot analysis of mRNAs extracted from the AA cell line showed transcription of some HdIV-encoded genes, although at low level. The effects of ecdysone treatment, HdIV re-infection and 42 °C heat-shock were analysed in the AA cell line. No effect was detected at the DNA (virus replication) or RNA (gene expression) levels, which may be due to the limitation of the present available tools.
Deletion of the Autographa californica nucleopolyhedrovirus chitinase KDEL motif and in vitro and in vivo analysis of the modified virus
Authors: Saville Giles P. , Patmanidi Alexandra L. , Possee Robert D. , King Linda A.
Published: March 2004

Infection of insect larvae with Autographa californica nucleopolyhedrovirus (AcMNPV) results in the liquefaction of the host, a process involving the action of virus-encoded chitinase and cathepsin gene products. Chitinase is localized in the endoplasmic reticulum (ER) during infection because of the presence of a C-terminal ER retrieval motif (KDEL). In this study, the KDEL coding region was removed from the chitinase gene so that expression of the modified chitinase remained under the control of its own gene promoter, at its native locus. The deletion of KDEL resulted in the redistribution of chitinase within the cell during virus infection. Chitinase lacking the KDEL motif was detectable at the plasma membrane and was also evident in the culture medium of virus-infected cells from as early as 12 h post-infection (p.i.). Secretion of chitinase from the cell continued up to 72 h p.i., until cytolysis. The biological activity of the recombinant virus in Trichoplusia ni larvae was enhanced, with a significant reduction in the lethal dose and lethal time associated with infection. Furthermore, a reduction in feeding damage caused by infected larvae was observed compared to AcMNPV-infected individuals.
The N-terminal half of the core protein of hepatitis C virus is sufficient for nucleocapsid formation
Authors: Majeau Nathalie , Gagné Valérie , Boivin Annie , Bolduc Marilène , Majeau Josée-Anne , Ouellet Dominique , Leclerc Denis
Published: March 2004

The core (C) protein of hepatitis C virus (HCV) appears to be a multifunctional protein that is involved in many viral and cellular processes. Although its effects on host cells have been extensively discussed in the literature, little is known about its main function, the assembly and packaging of the viral genome. We have studied the in vitro assembly of several deleted versions of recombinant HCV C protein expressed in E. coli. We demonstrated that the 75 N-terminal residues of the C protein were sufficient to assemble and generate nucleocapsid-like particles (NLPs) in vitro. However, homogeneous particles of regular size and shape were observed only when NLPs were produced from at least the first 79 N-terminal amino acids of the C protein. This small protein unit fused to the endoplasmic reticulum-anchoring domain also generated NLPs in yeast cells. These data suggest that the N-terminal half of the C protein is important for formation of NLPs. Similarities between the HCV C protein and C proteins of other members of the Flaviviridae are discussed.
Natural genetic variation in Arabidopsis identifies BREVIS RADIX, a novel regulator of cell proliferation and elongation in the root
Authors: Mouchel Céline F. , Briggs Georgette C. , Hardtke Christian S.
Published: March 2004

Mutant analysis has been tremendously successful in deciphering the genetics of plant development. However, less is known about the molecular basis of morphological variation within species, which is caused by naturally occurring alleles. In this study, we succeeded in isolating a novel regulator of root growth by exploiting natural genetic variation in the model plant Arabidopsis. Quantitative trait locus analysis of a cross between isogenized accessions revealed that a single locus is responsible for ∼80% of the variance of the observed difference in root length. This gene, named BREVIS RADIX (BRX), controls the extent of cell proliferation and elongation in the growth zone of the root tip. We isolated BRX by positional cloning. BRX is a member of a small group of highly conserved genes, the BRX gene family, which is only found in multicellular plants. Analyses of Arabidopsis single and double mutants suggest that BRX is the only gene of this family with a role in root development. The BRX protein is nuclear localized and activates transcription in a heterologous yeast system, indicating that BRX family proteins represent a novel class of transcription factors. Thus, we have identified a novel regulatory factor controlling quantitative aspects of root growth.
Photoreceptor ubiquitination by COP1 E3 ligase desensitizes phytochrome A signaling
Authors: Seo Hak Soo , Watanabe Etsuko , Tokutomi Satoru , Nagatani Akira , Chua Nam-Hai
Published: March 2004

Desensitization of activated receptors is an important mechanism for terminating signal transduction. Here we show that phytochrome (phy) A, a predominant photoreceptor for seedling deetiolation, colocalizes in nuclear bodies with CONSTITUTIVELY PHOTOMORPHOGENIC (COP) 1, a RING motif-containing E3 ligase. The phyA PAS domain interacts with the COP1 WD40 domain. Both the Pr and the Pfr forms of phyA, as well as the PHYA apoprotein, are ubiquitinated by COP1 in vitro. The phyA destruction rate is decreased in cop1 mutants and by expression of a COP1 RING motif mutant. Our results indicate that COP1 acts as an E3 ligase to regulate phyA signaling by targeting elimination of the phyA photoreceptor itself.
School‐based apprenticeships and traineeships in Australia
Authors: Smith Erica , Wilson Lou
Published: March 2004

In Australia, as in many other countries, initiatives are constantly being developed which aim to assist school students’ transition into work. One such initiative, which was introduced towards the end of the 1990s, was the introduction of school‐based apprenticeships and traineeships, often referred to by the umbrella term “school‐based new apprenticeships” (SBNAs). Students taking part in these programs, normally in the final two years of schooling (Years 11 and 12), combine part‐time work, study towards a vocational education and training (VET) qualification, and normal attendance at school. This paper reports on the first large‐scale research study of school‐based apprentices and trainees, which was carried out in late 2001 through a survey of students involved in the programs. The survey was carried out in the three Australian States with the highest numbers of school‐based apprentices and trainees, Queensland, Victoria and South Australia. The paper commences with a description of the nature of school‐based apprenticeships and a description of their introduction and rapid growth. It then gives an overview of the young people’s jobs, their learning and training, and concludes by discussing four problematic areas.
ICT‐supported team‐based experiential learning: classroom perspectives
Authors: Pauleen David J. , Marshall Stephen , Egort Irina
Published: March 2004

This paper presents and discusses an experiential learning‐based team‐based assignment, which makes extensive use of information and communication technology available in Blackboard. Student teams, composed of mature, post‐experience graduate students in a knowledge management class, were asked to perform a task requiring creativity and then to reflect on their individual and team experiences. Subjects were required to think about applying what they had learned to “real life” organizational settings. The results show that students find significant value in experiential learning processes. The findings also suggest students are able to apply knowledge management theories, which were taught in class lectures, to their team experiences and, further, to take the total learning experience combining theory and practice and usefully apply it to their work. Implications for experiential learning in the classroom and distance education are discussed.
Assessing the health and hygiene performance of apartment buildings
Authors: Ho D.C.W. , Leung H.F. , Wong S.K. , Cheung A.K.C. , Lau S.S.Y. , Wong W.S. , Lung D.P.Y. , Chau K.W.
Published: March 2004

The recent global outbreak of Severe Acute Respiratory Syndrome has aroused public concern on environmental health and hygiene. Develops a practical assessment scheme for assessing the health and hygiene performance of apartment buildings in Hong Kong. The scheme involves assessing a hierarchy of building factors that have a bearing on environmental qualities, and thus occupants’ health. Proposes an index method to integrate the assessment outcomes into a simple and user‐ friendly performance indicator for public consumption. The index can inform the public of the health and hygiene risk of different buildings and facilitate building owners, developers, and government bodies to make more informed and socially responsible decisions on environmental health and hygiene improvement. Although the assessment scheme is tailored for the institutional and cultural settings of Hong Kong, the assessment framework for the development of the scheme is also applicable to other cities.
Business continuity planning as a facilities management tool
Authors: Pitt Michael , Goyal Sonia
Published: March 2004

The inevitability of crises within the business environment suggests that the majority of organisations should have a business continuity plan (BCP). This work highlights those organisations that do not plan in this way and those which focus on information technology rather than utilising a holistic, integrated approach. Through extensive primary research this paper explores the current uptake and scope of business continuity planning within the business environment in the UK. The paper shows that the viability and effectiveness of BCPs is dependent on regular review, audit and testing.
The emerging role of the physical activity promoter within health promotion
Authors: Dawn James Angela , Halley Johnston Lynne
Published: March 2004

This study examines the extent to which physical activity specialists are emerging within health promotion. Hierarchical content analysis was used to analyse 70 telephone interviews with health promotion workers across England. The findings indicated that although many successful physical activity initiatives have, and are, being implemented throughout the country, the priority given to physical activity promotion, and the appointment of specialist physical activity posts, does not reflect the stated commitment from government health policy to boost physical activity levels in the general population. Physical activity promoters highlighted the need for partnership working in the delivery of physical activity initiatives. Failure to adapt to the implications of the changing structure within the health service may mean that within health promotion physical activity specialists do not achieve either the status or the outcomes they require.
The International Alliance for Child and Adolescent Mental Health and Schools (INTERCAMHS)
Authors: Weare Katherine
Published: March 2004

Outlines the history and objectives of the International Alliance for Child and Adolescent Mental Health and Schools (INTERCAMHS), a network of agencies and individuals that addresses mental health issues in schools. The Alliance promotes the international exchange of ideas and experience, and acts as a meeting place for a wide range of educationalists, mental health and other professionals interested in mental health.
Tree species distributions and local habitat variation in the Amazon: large forest plot in eastern Ecuador
Authors: Valencia Renato , Foster Robin B. , Villa Gorky , Condit Richard , Svenning Jens‐Christian , Hernández Consuelo , Romoleroux Katya , Losos Elizabeth , Magård Else , Balslev Henrik
Published: March 2004

1 We mapped and identified all trees ≥ 10 mm in diameter in 25 ha of lowland wet forest in Amazonian Ecuador, and found 1104 morphospecies among 152 353 individuals. The largest number of species was mid‐sized canopy trees with maximum height 10–20 m and understorey treelets with maximum height of 5–10 m.

2 Several species of understorey treelets in the genera Matisia and Rinorea dominated the forest numerically, while important canopy species were Iriartea deltoidea and Eschweilera coriacea.

3 We examined how species partition local topographic variation into niches, and how much this partitioning contributes to forest diversity. Evidence in favour of topographic niche‐partitioning was found: similarity in species composition between ridge and valley quadrats was lower than similarity between two valley (or two ridge) quadrats, and 25% of the species had large abundance differences between valley and ridge‐top. On the other hand, 25% of the species were generalists, with similar abundance on both valley and ridges, and half the species had only moderate abundance differences between valley and ridge.

4 Topographic niche‐partitioning was not finely grained. There were no more than three distinct vegetation zones: valley, mid‐slope, and upper‐ridge, and the latter two differed only slightly in species composition.

5 Similarity in species composition declined with distance even within a topographic habitat, to about the same degree as it declined between habitats. This suggests patchiness not related to topographic variation, and possibly due to dispersal limitation.

6 We conclude that partitioning of topographic niches does make a contribution to the α‐diversity of Amazonian trees, but only a minor one. It provides no explanation for the co‐occurrence of hundreds of topographic generalists, nor for the hundreds of species with similar life‐form appearing on a single ridge‐top.
Linear phase imaging using differential interference contrast microscopy
Authors: Arnison M. R. , Larkin K. G. , Sheppard C. J. R. , Smith N. I. , Cogswell C. J.
Published: March 2004

We propose an extension to Nomarski differential interference contrast microscopy that enables isotropic linear phase imaging. The method combines phase shifting, two directions of shear and Fourier‐space integration using a modified spiral phase transform. We simulated the method using a phantom object with spatially varying amplitude and phase. Simulated results show good agreement between the final phase image and the object phase, and demonstrate resistance to imaging noise.
A mathematical model of immunohistochemical preparations, which provides quantitative predictions
Authors: Holland T. , Holland H.
Published: March 2004

A mathematical model of the reaction between primary antibody and epitope is described using the Law of Mass Action to define the reaction quantitatively. The model explains some of the peculiar properties of immunohistochemical preparations. It also predicts that antibody excess over epitope will not increase staining intensity for very avid primary antibodies. This property can be exploited to measure the amount of epitope in histological sections. The assumptions of the model are not specific to immunohistochemistry, and such reasoning should be widely applicable to tests based on highly avid detection systems with high amplification of the initial signal.
Quantitative phase‐amplitude microscopy. III. The effects of noise
Authors: Paganin D. , Barty A. , McMahon P. J. , Nugent K. A.
Published: March 2004

We explore the effect of noise on images obtained using quantitative phase‐amplitude microscopy – a new microscopy technique based on the determination of phase from the intensity evolution of propagating radiation. We compare the predictions with experimental results and also propose an approach that allows good‐quality quantitative phase retrieval to be obtained even for very noisy data.
Quantitative phase amplitude microscopy IV: imaging thick specimens
Authors: Bellair C. J. , Curl C. L. , Allman B. E. , Harris P. J. , Roberts A. , Delbridge L. M. D. , Nugent K. A.
Published: March 2004

The ability to image phase distributions with high spatial resolution is a key capability of microscopy systems. Consequently, the development and use of phase microscopy has been an important aspect of microscopy research and development. Most phase microscopy is based on a form of interference. Some phase imaging techniques, such as differential interference microscopy or phase microscopy, have a low coherence requirement, which enables high‐resolution imaging but in effect prevents the acquisition of quantitative phase information. These techniques are therefore used mainly for phase visualization. On the other hand, interference microscopy and holography are able to yield quantitative phase measurements but cannot offer the highest resolution. A new approach to phase microscopy, quantitative phase‐amplitude microscopy (QPAM) has recently been proposed that relies on observing the manner in which intensity images change with small defocuses and using these intensity changes to recover the phase. The method is easily understood when an object is thin, meaning its thickness is much less than the depth of field of the imaging system. However, in practice, objects will not often be thin, leading to the question of what precisely is being measured when QPAM is applied to a thick object. The optical transfer function formalism previously developed uses three‐dimensional (3D) optical transfer functions under the Born approximation. In this paper we use the 3D optical transfer function approach of Streibl not for the analysis of 3D imaging methods, such as tomography, but rather for the problem of analysing 2D phase images of thick objects. We go on to test the theoretical predictions experimentally. The two are found to be in excellent agreement and we show that the 3D imaging properties of QPAM can be reliably predicted using the optical transfer function formalism.
Application of transmission electron microscopes to nanometre‐sized fabrication by means of electron beam‐induced deposition
Authors: Shimojo M. , Mitsuishi K. , Tanaka M. , Han M. , Furuya K.
Published: March 2004

Electron beam‐induced deposition was carried out using a scanning transmission electron microscope with a field emission gun to fabricate nanometre‐sized structures. A small amount of a metal–organic gas was introduced near the substrate in the microscope chamber, and focused electron beams were irradiated. Two‐ and three‐dimensional structures were fabricated by scanning the beam position. The minimum line width of the freestanding structures was 8 nm at a constant gas flux used. This line width of 8 nm is considered to be achieved by employing a high accelerating voltage, which leads to a small probe size, and the optimum scanning speed.
Comparison of conventional and microwave‐assisted processing of mouse retinas for transmission electron microscopy
Authors: Wendt K. D. , Jensen C. A. , Tindall R. , Katz M. L.
Published: March 2004

Conventional fixation and processing of mammalian retinal tissues for transmission electron microscopic (TEM) examination is slow and produces ultrastructural artefacts in the photoreceptor cell layer. Among these artefacts are gaps between photoreceptor outer segment disc membranes and between photoreceptor cells in the region of the retina where the cell nuclei are located. A study was undertaken to determine whether a much more rapid microwave‐assisted fixation and processing protocol would have an effect on the quality of ultrastructural preservation of the retina, particularly on the photoreceptor cell artefacts. The overall ultrastructural preservation of the retina was similar for the conventional and microwave‐assisted techniques. However, the magnitudes of the photoreceptor artefacts were significantly reduced when microwave irradiation was used during primary fixation and processing. It is clear that, at least for the retina, employing microwave irradiation during specimen preparation for TEM results in superior ultrastructural preservation with a substantial reduction in the time required for sample preparation.
Phase separation in molecular layers of macromolecules at the champagne–air interface
Authors: Peron N. , Meunier J. , Cagna A. , Valade M. , Douillard R.
Published: March 2004

Bubble and foam stability, which are essential for the hallmark of champagne, rely on the concentration of amphiphilic macromolecules originating from the grape, which form molecular layers at the interface between champagne and gas. Ellipsometry and Brewster angle microscopy experiments were conducted at the air–champagne interface to analyse the lateral organization of the layers of macromolecules. Several kinds of phase separations – leading in some cases to two‐dimensional foams – were identified. At the beginning of layer formation, condensed domains develop at the expense of dilute domains. Thereafter, phase separations occur within the condensed domains. These findings may allow advances in the implementation of methods predicting bubble and foam stability of champagnes.
Low‐cost, frequency‐domain, fluorescence lifetime confocal microscopy
Authors: Booth M. J. , Wilson T.
Published: March 2004

We describe the theory and implementation of a frequency‐domain fluorescence lifetime confocal microscope using switched diode laser illumination. Standard, communications‐type, radio‐frequency electronics are used to provide inexpensive modulation references and to perform phase‐sensitive detection. This allows the rapid acquisition of fluorescence intensity and lifetime images and their display in real time. We show fluorescence lifetime images of bead objects and fluorescence lifetime images of biological specimens from a single confocal scan.
Antigenic cross‐reactivity between different alleles of the Plasmodium falciparum merozoite surface protein 2
Authors: Felger Ingrid , Steiger Sylvia , Hatz Christoph , Smith Tom , Beck Hans‐Peter
Published: March 2004

The polymorphic domain of the gene encoding Plasmodium falciparum merozoite surface protein 2 (MSP2) was PCR amplified from blood of malaria patients, genotyped, and 19 distinct fragments were cloned and expressed in E. coli. The reactivity of naturally occurring antibodies against this panel of recombinant MSP2 antigens was tested using 67 homologous or heterologous sera from a serum bank of travel clinic patients. Sera from semi‐immune individuals strongly recognized almost all recombinant antigens. Sera from primary infected patients either did not react at all (9 sera), or reacted weakly against varying numbers of antigens (39 sera). The antigens that showed reactions were mostly of the allelic family corresponding to the infecting clone, but in very few cases also of the alternative allelic family. Single clone infections and repeated samples from the same individual were analysed in greater detail. Thus, we were able to quantify cross‐reactivity induced by a single P. falciparum infection. Within the two allelic families of MSP2, cross‐reactivity was observed between some but not all alleles of the same family, whereas antibodies cross‐reactive between variants belonging to different allelic families were detected in only a few cases.
IL‐4 dependent resistance to the tapeworm Mesocestoides corti (Cestoda) in mice
Authors: Rawat Jagveer , Dixon John B. , Macintyre Andrew R. , McGarry Helen F. , Taylor Mark J.
Published: March 2004

Three‐week Mesocestoides corti infections of C57BL/6 mice showed significantly raised parasite counts in animals with a targeted knockout of the IL‐4 gene. By contrast, antibody neutralization of IL‐5 and inhibition of eosinophilia had no effect on parasite numbers. In SV/129 mice, knockout of the interferon γ receptor and inducible nitric oxide synthase genes had no significant effect on parasite counts. In IL‐4–/–mice the dominant IgG1 antibody response was dramatically reduced, with a concomitant increase in IgG2a/b responses and a partial twofold reduction in IgM and IgE responses. We conclude that murine resistance to M. corti is dependent on IL‐4, but occurs independently of IL‐5 and eosinophils. This provides the first direct evidence for IL‐4 mediated immunity of mice to infection with a tissue‐dwelling platyhelminth.
Consumption of L‐arginine mediated byEntamoeba histolyticaL‐arginase (EhArg) inhibits amoebicidal activity and nitric oxide production by activated macrophages
Authors: Elnekave Keren , Siman‐Tov Rama , Ankri Serge
Published: March 2004

In this study we discuss the cloning and expression ofEntamoeba histolyticaarginase (EhArg), an enzyme that catalyses the hydrolysis ofl‐arginine tol‐ornithine and urea.l‐norvaline, a competitive inhibitor ofE. histolytical‐arginase, inhibits the growth of the parasite, which suggests that the catabolism ofl‐arginine mediated by EhArg is essential. Nitric oxide (NO) is an antimicrobial agent that inhibits some key enzymes in the metabolism ofEntamoeba histolytica. NO is synthesized by activated macrophages froml‐arginine, the substrate of NO synthase (NOS‐II). We show thatE. histolyticainhibits NO mediated amoebicidal activity of activated macrophages by consumingl‐arginine present in the medium.
Assessment of eosinophil cationic protein as a possible diagnostic marker for female genital schistosomiasis in women living in a Schistosoma haematobium endemic area
Authors: Midzi N. , Ndhlovu P. D. , Nyanga L. , Kjetland E. F , Reimert C. M. , Vennervald B. J. , Gomo E. , Mudenge G. , Friis H. , Gundersen S. G. , Mduluza T.
Published: March 2004

Eosinophil cationic protein (ECP) levels were measured in vaginal lavage extracts from 518 Zimbabwean reproductive women, age range 15–49 years, to assess the potential use of ECP as a diagnostic marker for female genital schistosomiasis (FGS). One hundred and fifty women had confirmed FGS status. These included 77 (cases) women who had ova in genital tissue and 73 (controls) women who had no ova in genital tissue. Participants were examined at baseline, 3 and 15 months post‐treatment with praziquantel. ECP levels were determined using the enzyme linked immunosorbent assay (ECP‐ELISA). ECP levels from 18 Norwegian women were used to calculate the diagnostic values of the test. FGS was diagnosed from the study population using genital biopsy and smears. Women were also diagnosed for urinary schistosomiasis using the urine filtration technique. The prevalence of urinary schistosomiasis was 39 % at baseline and this declined to 8% and 6% at 3 and 15 month post‐treatment surveys, respectively. There was a higher mean ECP level in women with FGS, 889·3 ng/mL (95% CI: 457·0–1327·5) compared to the endemic control group, 359·1 ng/mL (95%, CI: 227·3–490·9), P = 0·027. Mean ECP levels declined at 3 months following treatment of infected individuals. There was no correlation between ECP levels and tissue ova density, and urine egg intensity. The sensitivity, specificity, positive and negative predictive values for the ECP‐ELISA test were 35%, 80%, 65% and 53%, respectively. Our results indicate that FGS causes an inflammatory immune response that increases ECP levels in genital fluid. Treatment of schistosomiasis results in a regression of pathology and a decline in ECP levels. However, other factors such as allergy and microbial infection could also be responsible for increased ECP levels in genital mucosa. These conditions will affect the validity of the test in diagnosis of FGS.
Leishmania mexicana H‐line attenuated under pressure of gentamicin, potentiates a Th1 response and control of cutaneous leishmaniasis in BALB/c mice
Authors: Daneshvar Hamid , Hagan Paul , Phillips R. Stephen
Published: March 2004

An attenuated line of Leishmania mexicana (the L. mexicana H‐line) has been established by culturing in vitro under gentamicin pressure. BALB/c mice infected with the L. mexicana H‐line developed a CD4+Th1‐like response, indicated by the cytokine profile of their splenocytes stimulated by L. mexicana wild‐type (WT) promastigotes. This profile is sustained after these mice are challenged with L. mexicana WT. Control mice infected with L. mexicana WT alone developed a CD4+Th2‐like cytokine profile.In mice immunized with L. mexicana H‐line and then challenged with WT‐line, were eliminated when immunizing H‐line parasites persisted in the skin and draining popliteal lymph nodes (PLNs). In experiments in which mice were inoculated with attenuated and WT parasites at the same time, either at the same site or on separate sides of the mouse, growth of the WT parasites was significantly contained and controlled, indicating a possible therapeutic role for the attenuated parasites.
Comparison of an enzyme linked immunosorbent assay (ELISA) and a radioallergosorbent test (RAST) for detection of IgE antibodies to Brugia malayi
Authors: Wahyuni Sitti , Van Ree Ronald , Mangali Andarias , Supali Taniawati , Yazdanbakhsh Maria , Sartono Erliyani
Published: March 2004

The enzyme linked immunosorbent assay (ELISA) for specific IgE antibodies to Brugia malayi was compared with the radioallergosorbent test (RAST) for use in immunoepidemiological studies of lymphatic filariasis. Sera used were from individuals (aged 5–82 years) living in an area endemic for lymphatic filariasis in South Sulawesi, Indonesia. The percentage of positive IgE ELISA reactions (52·6%) among the population was lower than the percentage of positive RAST (94·5%). Although an overall significant concordance was found between the two assays (P < 0·001), 328 (42·7%) individuals with a positive RAST result were negative in the ELISA, whereas only 6 (0·8%) subjects were positive by ELISA, yet negative by RAST. When the population was divided into those with active infection (positive for anti‐filarial IgG4) and those not infected (mf‐negative and negative for anti‐filarial IgG4), the correlation between the two tests was higher in the IgG4‐positive (rho = 0·70) than in the IgG4‐negative (rho = 0·52) group. These results indicate that in assessment of B. malayi specific IgE antibody, RAST is superior to ELISA. However, given the use of radioactivity in the RAST method and given our results obtained in subjects with high anti‐filarial IgG4, one could consider using the IgE‐ELISA in areas with high endemicity for filariasis. In areas with low endemicity or where control programs are implemented, sera will have to be tested by RAST.
The Cogeneration Potential of the Sugar Industry in Vietnam
Authors: Bhattacharyya Subhes C. , Thang Dang Ngoc Quoc
Published: March 2004

Vietnam produces about 15 million tons of sugarcane per year and about five mt of bagasse. There is the potential for cogeneration using bagasse, which can also help overcome power shortages in the country. This paper analyses the potential for cogeneration from the sugar industry in Vietnam under three different scenarios and finds that between 100 and 300 megawatts of power‐generating capacity could be supported by the bagasse generated from sugar mills, depending on the technology considered for sugar mills and cogeneration and the possibility of renovation of the existing mills.

The paper also assesses the expense of cogeneration and finds it to be a cost‐effective option for all types of sugar mill. It is found that the cost savings from cogeneration would more than offset the cost of introducing cogeneration in sugar mills with inefficient caneprocessing technologies. Sugar mills with modern technologies would have a significant amount of excess power and most of these plants would break‐even if they sold excess power at around 4.5 cents per kilowatt hour. The break‐even cost and the average production cost are sensitive to the investment cost assumptions. The paper thus suggests that cogeneration from the sugar industry is an attractive option for investors in existing mills or new sugar mills alike.
Current management of alcoholic liver disease
Authors: Tome S. , Lucey M. R.
Published: March 2004

Alcoholic liver disease, including acute alcoholic hepatitis and alcoholic cirrhosis, is a major cause of morbidity and mortality in the Western world. Abstinence remains the cornerstone of management of all forms of alcoholic liver disease. Recent research, which has elucidated the mechanisms of alcohol‐induced liver injury, offers the prospect of advances in the management of alcoholic liver disease. We review the most recent data on the efficacy of treatment of acute alcoholic injury, including nutritional support, corticosteroids, anti‐inflammatory agents and antioxidants, and agents that are directed against the progression to fibrosis, such as colchicines, propylthiouracil and antioxidants. Although these therapies offer a tantalizing glimpse into a future that may include therapies that directly alter the process of injury and repair in the liver, none has been shown consistently to improve the course of alcoholic liver damage. Consequently, liver transplantation remains an ultimate option for selected patients with liver failure due to chronic alcoholic liver damage.
The risk of post‐operative complications associated with infliximab therapy for Crohn's disease: a controlled cohort study
Authors: Marchal L. , D'Haens G. , Van Assche G. , Vermeire S. , Noman M. , Ferrante M. , Hiele M. , Bueno De Mesquita M. , D'Hoore A. , Penninckx F. , Rutgeerts P.
Published: March 2004

Background : By temporarily suppressing the immune response, the anti‐tumour necrosis factor agent, infliximab, may increase the risk of peri‐operative complications.

Aim : To test this hypothesis for intestinal resection in a cohort of 313 Crohn's disease patients treated with infliximab. Forty received one or more infusions prior to intestinal resection (31/40 within 12 weeks).

Methods : The post‐operative events of these patients were compared with those of a control group (infliximab naive) of 39 patients adjusted for age, gender and surgical procedure. Early (10 days) and late (3 months) major or minor complications were identified.

Results : The incidence of early minor (15.0% vs. 12.8%) and major (12.5% vs. 7.7%) and late minor (2.5% vs. 5.1%) and major (17.5% vs. 12.8%) complications and the mean hospital stay after surgery (10.3 ± 4.0 days vs. 9.9 ± 5.5 days) were similar in both groups. A trend towards an increased early infection rate was found in infliximab pre‐treated patients (6 vs. 1; P = 0.10), but more patients in this group received corticosteroids and/or immunosuppressives (29 vs. 16 patients; P < 0.05).

Conclusion : The use of infliximab before intestinal resection does not prolong the hospital stay and does not increase the rate of post‐operative complications.