bluuebunny/crossref_metadata_2025 huggingface dataset:
The secreted form of the p40 subunit of interleukin (IL)‐12 inhibits IL‐23 functions and abrogates IL‐23‐mediated antitumour effects
Authors: Shimozato Osamu , Ugai Shin‐ichi , Chiyo Masako , Takenobu Hisanori , Nagakawa Hiroyasu , Wada Akihiko , Kawamura Kiyoko , Yamamoto Hiroshi , Tagawa Masatoshi
Published: October 2005

Interleukin (IL)‐23 is a heterodimeric cytokine consisting of a novel p19 molecule and the p40 subunit of IL‐12. Since secreted p40 can act as an antagonist for IL‐12, we investigated whether p40 also inhibited IL‐23‐mediated immunological functions. p40 did not induce interferon (IFN)‐γ or IL‐17 production from splenocytes but impaired IL‐23‐induced cytokine production by competitive binding to the IL‐23 receptors. Furthermore, a mixed population of murine colon carcinoma Colon 26 cells transduced with the p40 gene and those transduced with the IL‐23 gene developed tumours in syngenic mice, whereas the IL‐23‐expressing Colon 26 cells were completely rejected. p40 also suppressed IFN‐γ production of antigen‐stimulated splenocytes and IL‐23‐mediated cytotoxic T‐lymphocyte activities in the mice that rejected Colon 26 cells expressing IL‐23. p40 can thereby antagonize IL‐23 and is a possible therapeutic agent for suppression of IL‐23 functions.
Induction of interferon‐γ from natural killer cells by immunostimulatory CpG DNA is mediated through plasmacytoid‐dendritic‐cell‐produced interferon‐α and tumour necrosis factor‐α
Authors: Marshall Jason D. , Heeke Darren S. , Abbate Christi , Yee Priscilla , Van Nest Gary
Published: October 2005

Immunostimulatory sequences (ISS) that contain CpG motifs have been demonstrated to exert antipathogen and antitumour immunity in animal models through several mechanisms, including the activation of natural killer (NK) cells to secrete interferon‐γ (IFN‐γ) and to exert lytic activity. Since NK cells lack the ISS receptor TLR9, the exact pathway by which NK cells are activated by ISS is unclear. We determined that ISS‐induced IFN‐γ from NK cells is primarily dependent upon IFN‐α release from plasmacytoid dendritic cells (PDCs), which directly activates the NK cell. However, further analysis indicated that other PDC‐released soluble factor(s) may contribute to IFN‐γ induction. Indeed, tumour necrosis factor‐α (TNF‐α) was identified as a significant contributor to ISS‐mediated activation of NK cells and was observed to act in an additive fashion with IFN‐α in the induction of IFN‐γ from NK cells and to up‐regulate CD69 expression on NK cells. This activity of TNF‐α, however, was dependent upon the presence of PDC‐derived factors such as type I interferon. These results illustrate an important function for type I interferon in innate immunity, which is not only to activate effectors like NK cells directly, but also to prime them for enhanced activation by other factors such as TNF‐α.
Efficient secretion of a folded protein domain by a monomeric bacterial autotransporter
Authors: Skillman Kristen M. , Barnard Travis J. , Peterson Janine H. , Ghirlando Rodolfo , Bernstein Harris D.
Published: October 2005

Bacterial autotransporters are proteins that contain a small C‐terminal ‘β domain’ that facilitates translocation of a large N‐terminal ‘passenger domain’ across the outer membrane (OM) by an unknown mechanism. Here we used EspP, an autotransporter produced by Escherichia coli 0157:H7, as a model protein to gain insight into the transport reaction. Initially we found that the passenger domain of a truncated version of EspP (EspPΔ1‐851) was translocated efficiently across the OM. Blue Native polyacrylamide gel electrophoresis, analytical ultracentrifugation and other biochemical methods showed that EspPΔ1‐851 behaves as a compact monomer and strongly suggest that the channel formed by the β domain is too narrow to accommodate folded polypeptides. Surprisingly, we found that a folded protein domain fused to the N‐terminus of EspPΔ1‐851 was efficiently translocated across the OM. Further analysis revealed that the passenger domain of wild‐type EspP also folds at least partially in the periplasm. To reconcile these data, we propose that the EspP β domain functions primarily to target and anchor the protein and that an external factor transports the passenger domain across the OM.
A novel palmitoyl acyl transferase controls surface protein palmitoylation and cytotoxicity in Giardia lamblia
Authors: Touz María C. , Conrad John T. , Nash Theodore E.
Published: October 2005

The intestinal protozoan parasite Giardia lamblia undergoes surface antigenic variation whereby one of a family of structurally related variant‐specific surface proteins (VSPs) is replaced in a regulated process by another antigenically distinct VSP. All VSPs are type I membrane proteins that have a conserved hydrophobic sequence terminated by the invariant hydrophilic amino acids, CRGKA. Using transfected Giardia constitutively expressing HA‐tagged VSPH7 and incubated with radioactive [3H]palmitate, we demonstrate that the palmitate is attached to the Cys in the conserved CRGKA tail. Surface location of mutant VSPs lacking either the CRGKA tail or its Cys is identical to that of wild‐type VSPH7 but non‐palmitoylated mutants fail to undergo complement‐independent antibody specific cytotoxicity. In addition, membrane localization of non‐palmitoylated mutant VSPH7 changes from a pattern similar to rafts to non‐rafts. Palmitoyl transferases (PAT), responsible for protein palmitoylation in other organisms, often possess a cysteine‐rich domain containing a conserved DHHC motif (DHHC‐CRD). An open reading frame corresponding to a putative 50 kDa Giardia PAT (gPAT) containing a DHHC‐CRD motif was found in the Giardia genome database. Expression of epitope‐tagged gPAT using a tetracycline inducible vector localized gPAT to the plasma membrane, a pattern similar to that of VSPs. Transfection with gPAT antisense producing vectors inhibits gPAT expression and palmitoylation of VSPs in vitro confirming the function of gPAT. These results show that VSPs are palmitoylated at the cysteine within the conserved tail by gPAT and indicate an essential function of palmitoylation in control of VSP‐mediated signalling and processing.
Pyridoxine is required for post‐embryonic root development and tolerance to osmotic and oxidative stresses
Authors: Chen Hao , Xiong Liming
Published: October 2005

Pyridoxine (vitamin B6) is a cofactor required by numerous enzymes in all cellular organisms. Plants are the major source of vitamin B6 for animals, yet the biosynthesis pathway and the function of vitamin B6 in plants are not well elucidated. In this study, an Arabidopsis pyridoxine synthase gene PDX1 was characterized and its in vivo functions were investigated. The PDX1 gene was expressed in all plant parts examined and its expression level was not significantly regulated by abiotic stress or the phytohormone abscisic acid. In roots, PDX1 was highly expressed in a defined region behind the root tips that undergoes rapid cell division. The PDX1 protein was mainly associated with the plasma membrane and endomembranes, implying a potential involvement of vitamin B6 in membrane function. To reveal the in vivo role of PDX1, Arabidopsis insertional mutants were isolated. Strikingly, the pdx1 knockout mutants were impaired in root growth and early seedling development. The stunted roots resulted from both reduced cell division and elongation. Supplementation of the growth media with pyridoxine or reintroduction of the wild‐type PDX1 gene into the mutants completely restored the mutant growth, demonstrating that PDX1 is required for pyridoxine biosynthesis in planta. In addition to the developmental defects, pdx1 mutants are hypersensitive to osmotic stress and oxidative stress. These mutant seedlings had increased peroxidation of membrane lipids following UV treatment. Our study establishes a critical role of vitamin B6 in plant development and stress tolerance and suggests that vitamin B6 may represent a new class of antioxidant in plants.
Arabidopsis thaliana subcellular responses to compatible Erysiphe cichoracearum infections
Authors: Koh Serry , André Aurélie , Edwards Herb , Ehrhardt David , Somerville Shauna
Published: October 2005

Subcellular events of Erysiphe cichoracearum infections of epidermal cells were visualized in living tissues of Arabidopsis plants carrying various green fluorescent protein (GFP)‐tagged organelles via laser scanning confocal microscopy. Early in the infection sequence, cytoplasm and organelles moved towards penetration sites and accumulated near penetration pegs. Peroxisomes appeared to accumulate preferentially relative to the cytoplasm at penetration sites. Another early event, which preceded haustorium formation, was the aggregation of some GFP‐tagged plasma membrane marker proteins into rings around penetration sites, which extended across cell‐wall boundaries into neighboring cells. This feature localized to sites where papillae were deposited. The extrahaustorial membrane (EHM) encases the fungal feeding structure, the haustorium, separating it from the host cytoplasm. Eight plasma membrane markers were excluded from the EHM and remained in a collar‐like formation around the haustorial neck. These observations support the suggestions that the EHM is a unique, specialized membrane and is different from the plasma membrane. Our results suggested two possibilities for the origin of the EHM: invagination of the plasma membrane coupled with membrane differentiation; or de novo synthesis of the EHM by targeted vesicle trafficking.
Evaluation of COBAS AmpliPrep nucleic acid extraction in conjunction with COBAS AmpliScreen HBV DNA, HCV RNA and HIV‐1 RNA amplification and detection
Authors: Koppelman M. H. G. M. , Sjerps M. C. , Reesink H. W. , Cuypers H. T. M.
Published: October 2005

Background and Objectives  This report describes the evaluation of the COBAS AmpliPrep instrument for fully automated generic nucleic acid extraction in conjunction with hepatitis B virus (HBV) DNA, hepatitis C virus (HCV) RNA, and human immunodeficiency virus (HIV)‐1 RNA COBAS AmpliScreen amplification and detection using serial dilutions of the WHO international standards (IS) and the PeliCheck reference panels.

Materials and Methods  Serial diluted samples of the WHO IS and the PeliCheck reference panels were tested 24 times to determine the HBV DNA, HCV RNA and HIV‐1 RNA detection limits by Probit analysis. The existence and extent of cross‐contamination were assessed by testing alternating high titre HBV DNA‐positive and ‐negative samples. The specificity of the AmpliPrep–AmpliScreen test for HBV was determined by testing 232 minipools consisting of six donations, all negative for HCV/HIV‐1 nucleic acid testing (NAT) and HBsAg. In addition, a HBV genotypes A–G panel was tested.

Results  The respective 95% detection limits (and 95% CI) on the WHO IS and on the PeliCheck reference panels were 6·7 (4·3–13) IU/ml and 123 (68–301) gEq/ml for HBV DNA, 23 (11–106) IU/ml and 126 (84–233) gEq/ml for HCV RNA, and 187 (108–422) IU/ml and 183 (108–434) gEq/ml for HIV‐1 RNA. Based on the WHO IS and the PeliCheck reference panels, no significant differences in sensitivity for HBV and HCV were found between AmpliPrep and the licensed MultiPrep extraction method. The sensitivity of AmpliPrep–AmpliScreen for HIV‐1 was probably twofold lower as compared to the MultiPrep–AmpliScreen method. No cross contamination was observed. All 232 minipools were HBV NAT‐negative. The AmpliPrep–AmpliScreen test for HBV detected HBV genotypes A–G with equal sensitivity.

Conclusions  The AmpliPrep instrument combined with the AmpliScreen assays for HBV, HCV and HIV‐1 is robust and suitable for NAT donor screening. The sensitivity criteria for HIV‐1 and HCV as defined by the Paul Ehrlich Institute and the Food and Drug Administration for minipool NAT screening are met by this system.

Single sentence summary  Generic COBAS AmpliPrep nucleic acid extraction in conjunction with COBAS AmpliScreen detection for HBV, HCV and HIV‐1.
Let's be PALS: User‐Driven Organizational Change in Healthcare*
Authors: Buchanan David , Abbott Stephen , Bentley Jane , Lanceley Anne , Meyer Julienne
Published: October 2005

This paper explores user‐driven organizational change in the National Health Service (NHS). The NHS Plan (Department of Health, 2000) created Patient Advice and Liaison Services (PALS) to provide information, solve problems and drive user‐led change. Evidence is drawn from a study of PALS in London acute, primary care, mental health and specialist trusts, drawing on discussion forums, interviews with PALS officers and documentation. From context and role profiles, two conclusions are evident. First, organizational instability, boundary disputes, variable management support, resource limitations, financial insecurity and multi‐site working characterize the context in which PALS operate, and the officer role is characterized by problem diversity, overlap with complaints systems, monitoring problems, relationship building and ‘serial users’. Second, these context and role attributes restrict PALS to ‘repair and maintenance’, ensuring that established systems work correctly. While PALS sit on the bottom rung of a ‘participation ladder’, their contribution is more than tokenistic. However, a processual perspective demonstrates how a fluid, networked, and diversified context isolates PALS structures from management decision‐making, constraining their power base, and inhibiting the promotion of substantive change agendas.
Managing Change Across Boundaries: Boundary‐Shaking Practices1
Authors: Balogun Julia , Gleadle Pauline , Hailey Veronica Hope , Willmott Hugh
Published: October 2005

To date, boundary spanning has primarily been conceived of as an activity relating an organization to its environment, including other organizations with which it cooperates and competes. In contrast, this study focuses on the boundary spanning practices of individuals acting as change agents to implement boundary‐shaking change initiatives across intra‐organizational boundaries. These boundary‐shaking individuals all work for blue‐chip organizations in sectors as diverse as pharmaceuticals, consultancy and automotive. The change initiatives are equally diverse, including post‐merger integration, exploitation of across‐business synergies and implementing more integrative structures. Through our examination of boundary‐shakers we are able to extend what we know about internal change agency and change agent skills and practices. Our starting point is that organizations are comprised of networks of people with a degree of common interest. Our research shows our research subjects to be active movers and shakers in these networks, using their knowledge of the organizational political context and the motivations of others to create new networks (or new meanings within old networks), which then enables them to pursue their change objectives.
Subjects, objects and intonational phrasing in spanish and portuguese*
Authors: Elordieta Gorka , Frota Sónia , Vigário Marina
Published: October 2005

Abstract. This article investigates the role of prosodic length and syntactic complexity on intonational phrasing in Spanish and European Portuguese. Spanish presents a clear tendency to divide utterances into (S)(VO) phrasings, depending on branchingness. In EP (SVO) is the predominant phrasing, but a long branching subject can trigger the phrasing (S)(VO). The main differences between the two languages are analyzed as arising from two properties: the different syntactic position of subjects (external or internal to Extended VP) and the different parameters of prosodic weight (number of syllables vs. number of words/branchingness) realized by each language. Constraints of the syntax‐prosody interface and prosodic constraints on the maximum size of major phrases refer to these properties and produce different outcomes. The preference shared by EP and Spanish to have the material in a VP contained in the same major phrase (disallowing (V)(O) phrasings) also stems from a syntax‐phonology constraint.
Effects of prosodic boundaries on syntactic disambiguation*
Authors: Kang Soyoung , Speer Shari R.
Published: October 2005

Abstract. We present results of four experiments that examined the role of prosodic boundaries in sentence comprehension of syntactically ambiguous constructions in Korean. Considering the fact that there has been relatively less work on languages other than English on this topic, it will be interesting to see how the previous findings of prosodic effects on sentence comprehension will be manifested in this language. The main focus in this study was to see how prosodic structures interact with the head‐final and pro‐drop nature of this language. Results show robust effects of prosodic boundaries on resolving syntactically ambiguous sentences, confirming previous findings on the role of prosody on sentence comprehension.
Intonational phrasing and constituency in language production and comprehension*
Authors: Watson Duane , Gibson Edward
Published: October 2005

Abstract.  In this paper, we investigate the relationship between intonational phrase boundaries and syntax in production and comprehension. Watson & Gibson (2004a) proposed that the likelihood of an intonational boundary at a word boundary is a function of 1) the size of the most recently completed constituent and 2) the size of the upcoming constituent if it is not an argument of the most recent head. We explore an alternate hypothesis to (1): the distance of integration between an upcoming word and its attachment site in the sentence influences the likelihood of an intonational boundary. In a production experiment (Experiment 1), we found that speakers’ intonational phrasing patterns were consistent with Watson & Gibson's original hypothesis. We then present two studies of sentence comprehension using converging paradigms which test the hypothesis that listeners exploit the relationship between syntax and the production‐based intonational boundaries by using a special parsing heuristic. In particular, we propose that listeners prefer not to attach incoming words to lexical heads that are followed by an intonational boundary. This hypothesis is validated in both Experiments 2 and 3.
Development of Social Health Insurance in Mongolia: Successes, Challenges and Lessons
Authors: Bayarsaikhan Dorjsuren , Kwon Soonman , Ron Aviva
Published: October 2005

This paper examines the process of developing social health insurance in Mongolia, and its successes, challenges and lessons. The government of Mongolia introduced social health insurance in 1994, which is compulsory for all public and private sector employees and low‐income and vulnerable population groups. The scheme also provided voluntary insurance for unemployed people of working age. About 95 per cent of the population was covered by health insurance within the first two years thanks to a high level of government subsidy for vulnerable population groups. The insurance benefit initially covered nearly all inpatient services except the treatment of some specified chronic and infectious diseases, which were directly funded by the government. The scheme not only had many successes but also faced challenges in maintaining universal coverage. The new financing arrangement has provided little financial incentive for healthcare providers to contain health expenditure, contributing to rapid health cost inflation. In addition to reforming the payment system for providers, there has been an increasing need to expand benefits into ambulatory care. The development of compulsory health insurance in Mongolia shows that a prepaid health insurance mechanism based on risk sharing and fund pooling is feasible in low‐income countries given political commitment and government financial support for vulnerable population groups.
Neuronal protection by sirtuins in Alzheimer's disease
Authors: Anekonda Thimmappa S. , Reddy P. Hemachandra
Published: October 2005

Silent information regulator 2, a member of NAD+‐dependent histone deacetylase in yeast, and its homologs in mice and humans, participate in numerous important cell functions, including cell protection and cell cycle regulation. The sirtuin family members are highly conserved evolutionarily, and are predicted to have a role in cell survival. The science of sirtuins is an emerging field and is expected to contribute significantly to the role of sirtuins in healthy aging in humans. The role of sirtuins in neuronal protection has been studied in lower organisms, such as yeast, worms, flies and rodents. Both yeast Sir2 and mammalian sirtuin proteins are up‐regulated under calorie‐restricted and resveratrol treatments. Increased sirtuin expression protects cells from various insults. Caloric restriction and antioxidant treatments have shown useful effects in mouse models of aging and Alzheimer's disease (AD) and in limited human AD clinical trials. The role sirtuins may play in modifying and protecting neurons in patients with neurodegenerative diseases is still unknown. However, a recent report of Huntington's disease revealed that Sirtuin protects neurons in a Huntington's disease mouse model, suggesting that sirtuins may protect neurons in patients with neurodegenerative diseases, such as AD. In this review, we discuss the possible mechanisms of sirtuins involved in neuronal protection and the potential therapeutic value of sirtuins in healthy aging and AD.
Cocaine‐induced CREB phosphorylation in nucleus accumbens of cocaine‐sensitized rats is enabled by enhanced activation of extracellular signal‐related kinase, but not protein kinase A
Authors: Mattson Brandi J. , Bossert Jennifer M. , Simmons Danielle E. , Nozaki Naohito , Nagarkar Deepti , Kreuter Justin D. , Hope Bruce T.
Published: October 2005

Repeated cocaine administration to rats outside their home cages sensitizes the behavioral effects of the drug, and enhances induction of the immediate early gene product Fos in nucleus accumbens. We hypothesized that the same treatment regimen would also enhance cocaine‐induced activation of intracellular signaling kinases that phosphorylate cyclic AMP‐regulated element‐binding protein (CREB), an important mediator of c‐fos transcription. Phosphorylation levels of extracellular signal‐regulated kinase (ERK)/mitogen‐activated protein kinase (MAPK), calcium/calmodulin kinases (CaMKs) II and IV, and CREB were used to assess endogenous functional activity of these signaling molecules in rats behaviorally sensitized outside their home cages. Protein kinase A (PKA)‐specific phosphorylation of Ser845 in the α‐amino‐3‐hydroxy‐5‐methylisoxazole‐4‐propionate (AMPA) receptor subunit GluR1 was used to assess endogenous functional activity of PKA. Using western blots and immunohistochemistry, we detected cocaine‐induced CREB phosphorylation after repeated cocaine administration, but not after repeated saline administration. Using western blots and MAPK activity assays, we found that cocaine‐induced phosphorylation and activation of ERK, but not of CaMKs II or IV or GluR1, was augmented in nucleus accumbens of cocaine‐sensitized rats. Unilateral infusions of the MAPK kinase inhibitor U0126 into nucleus accumbens attenuated cocaine‐induced ERK and CREB phosphorylation in cocaine‐sensitized rats. In contrast, unilateral infusions of the PKA inhibitor Rp‐isomer of adenosine‐3′,5′‐cyclicmonophosphorothioate (Rp‐cAMPs) did not affect cocaine‐induced CREB phosphorylation. Therefore, enhanced activation of ERK, but not PKA, enables and mediates cocaine‐induced CREB phosphorylation in nucleus accumbens of rats that are sensitized by repeated cocaine administration outside their home cages.
Metamorphic history of serpentinite mylonites from the Happo ultramafic complex, central Japan
Authors: NOZAKA T.
Published: October 2005

Serpentinite mylonites from the Happo ultramafic complex show evidence of two stages of mylonitization at different temperature conditions. Peridotite mylonites exhibit two types of olivine – porphyroclasts and neoblasts – produced at the earlier stage. The olivine neoblasts have a stretching lineation with a fabric suggesting plastic deformation along (0 1 0) [0 0 1]. In addition to the olivine fabric, the stable association of olivine, orthopyroxene and tremolite in the peridotites that survived later serpentinization, and the Si and Na contents of tremolite, suggest that the earlier mylonitization took place at temperatures between 700 and 800 °C. Later mylonitization was associated with high‐temperature serpentinization to form serpentinite mylonites. In contrast to a common type of serpentinite in orogenic belts, the serpentinite mylonites are cohesively foliated, rich in olivine and diopside, and poor in antigorite. The diopside has low Al, Cr and Na contents typical of a retrograde origin, and the olivine has a homogeneous composition except in areas subjected to contact metamorphism at a later stage. Modal composition and mineral chemistry suggest that the serpentinite mylonites were formed by a hydration reaction of tremolite and olivine to produce diopside and antigorite under stable conditions of olivine, at temperatures between 400 and 600 °C. Later‐stage mylonitization has preferentially been superimposed on the earlier‐stage mylonite zone with a common direction of foliation. The difference in temperature between the two mylonitization stages suggests that the shear zone was episodically active during the emplacement of the Happo complex. Conditions of relatively high temperature for serpentinization at a convergent plate boundary and high permeability caused by the early mylonitization favoured the formation of the serpentinite mylonites.
Effect of Cataract Surgery on Cognitive Function in Older Adults
Authors: Hall Tyler Andrew , McGwin Gerald , Owsley Cynthia
Published: October 2005

Objectives: To assess whether cataract surgery has an effect on cognitive function in older adults.

Design: Longitudinal.

Setting: Assessment of patients seen in eye clinics.

Participants: Patients with no cataract (n=92), patients with cataract who elected surgery (n=122), and patients with cataract who declined surgery (n=87).

Measurements: At baseline and 1‐year follow‐up visits, the following information was obtained: demographic, health behavior, general health status, medication use, depressive symptoms, cognitive function, and visual function information. This information was compared within and between groups at baseline and follow‐up visits.

Results: Mattis Organic Mental Syndrome Screening Examination scores at baseline and follow‐up varied across the three groups, with the cataract/no surgery group having the highest scores (more cognitive impairment) and the no‐cataract group having the lowest scores (less cognitive impairment). For the within‐group analysis, at follow‐up, the cataract/no surgery group and the cataract/surgery group had significantly less cognitive impairment (P<.001), whereas the no‐cataract group experienced no change. For those with cataract, there were no associations between changes in visual function and cognitive function.

Conclusion: Improvement in cognitive function may occur after cataract surgery but cannot be attributed to the cataract surgery per se or to improved visual function. Clinicians may find this information useful when discussing the nonvisual outcomes of cataract surgery with patients.
Lack of Soluble TNF‐receptors in Women with Recurrent Spontaneous Abortion and Possibility for its Correction
Authors: Chernyshov Victor P. , Vodyanik Maxim A. , Pisareva Svetlana P.
Published: October 2005

Problem

Tumor necrosis factor (TNF) and soluble TNF receptors (sTNF‐Rs) system related with Th1 and Th2 and activity of NF‐κB/IκB regulatory system. This study was designed to compare sTNF‐R1 and sTNF‐R2 production (shedding) and levels of late activated CD8+ T‐lymphocytes in non‐pregnant (n = 30) and pregnant (n = 20) normal women and non‐pregnant (n = 20) and pregnant (n = 30) RSA women. Effects of progesterone (natural structure) injections in RSA women were studied.

Methods of study

Levels of sTNF‐R1, sTNF‐R2, TNF in peripheral blood serum were detected by enzyme‐linked immunosorbent assay. Lymphocyte subsets were estimated by multicolor flow cytometry. NK cell cytotoxic activity of peripheral blood lymphocytes (PBL) in whole blood against K562 targets was determined using Europium‐release cytotoxicity assay. Mitogen‐induced proliferative response of PBL to PHA‐P, Con A and PWM were determined by standard 3H‐thymidine incorporation assay.

Results

Levels of soluble TNF‐R1 and TNF‐R2 in normal pregnancy were elevated when compared with non‐pregnant normal women and pregnant RSA women. Levels of late activated CD8+ T‐lymphocytes in normal pregnancy were decreased but no changes were detected in RSA women. After progesterone therapy (i.m. injections of 2.5% oil solution) in RSA women elevation of sTNF‐R1 and sTNF‐R2 to normal pregnancy ranges was observed. No changes in levels of late activated CD8+ T‐lymphocytes after progesterone treatment were detected.

Conclusions

Elevation of levels of sTNF‐R1, sTNF‐R2 and decrease of late activated cytotoxic T‐lymphocytes are pronounce markers of normal human pregnancy. In RSA women there are no elevation of sTNF‐R1 and sTNF‐R2 levels during pregnancy. This deficiency may be restored by progesterone treatment.
Perforin and Fas/FasL Cytolytic Pathways at the Maternal–Fetal Interface
Authors: Crncic Tatjana Bogovic , Laskarin Gordana , Juretic Koraljka , Strbo Natasa , Dupor Jana , Srsen Suzana , Randic Ljiljana , Bouteiller Philippe Le , Tabiasco Julie , Rukavina Daniel
Published: October 2005

The immunogenetic enigma of maternal acceptance of the fetal semiallograft has been termed an immunological paradox. The first trimester decidua is heavily infiltrated with CD56brightCD16− uterine natural killer (uNK) cells which must be prepared to respond to potential pathogen challenges and still be able to control immune responses that allow the development of the fetus. The significant presence of cytolytic mediators, perforin and Fas/Fas ligand (FasL), at the maternal–fetal interface raises a question of their role(s) in the immunological interrelations between maternal tissues and trophoblast cells. As uNK cells in vitro lyse target cell lines (K562, P815 and P815Fas) using these effector molecules, it seems that, although immunocompetent, their cytotoxicity is not directed against trophoblast during normal pregnancy. Therefore, it is generally believed that the hormonal and Th1/Th2 cytokine balance plays an important role in the tolerance and maintenance of pregnancy. This paper gives an overview of the recent findings on the complex immunological events that occur at the maternal–fetal interface.
The N‐glycans of yellow jacket venom hyaluronidases and the protein sequence of its major isoform in Vespula vulgaris
Authors: Kolarich Daniel , Léonard Renaud , Hemmer Wolfgang , Altmann Friedrich
Published: October 2005

Hyaluronidase (E.C. 3.2.1.35), one of the three major allergens of yellow jacket venom, is a glycoprotein of 45 kDa that is largely responsible for the cross‐reactivity of wasp and bee venoms with sera of allergic patients. The asparagine‐linked carbohydrate often appears to constitute the common IgE‐binding determinant. Using a combination of MALDI MS and HPLC of 2‐aminopyridine‐labelled glycans, we found core‐difucosylated paucimannosidic glycans to be the major species in the 43–45 kDa band of Vespula vulgaris and also in the corresponding bands of venoms from five other wasp species (V. germanica, V. maculifrons, V. pensylvanica, V. flavopilosa and V. squamosa). Concomitant peptide mapping of the V. vulgaris 43 kDa band identified the known hyaluronidase, Ves v 2 (SwissProt P49370), but only as a minor component. De novo sequencing by tandem MS revealed the predominating peptides to resemble a different, yet homologous, sequence. cDNA cloning retrieved a sequence with 58 and 59% homology to the previously known isoform and to the Dolichovespula maculata and Polistes annularis hyaluronidases. Close homologues of this new, putative hyaluronidase b (Ves v 2b) were also the major isoform in the other wasp venoms.
Molecular basis for substrate recognition and drug resistance from 1.1 to 1.6 Å resolution crystal structures of HIV‐1 protease mutants with substrate analogs
Authors: Tie Yunfeng , Boross Peter I. , Wang Yuan‐Fang , Gaddis Laquasha , Liu Fengling , Chen Xianfeng , Tozser Jozsef , Harrison Robert W. , Weber Irene T.
Published: October 2005

HIV‐1 protease (PR) and two drug‐resistant variants – PR with the V82A mutation (PRV82A) and PR with the I84V mutation (PRI84V) – were studied using reduced peptide analogs of five natural cleavage sites (CA‐p2, p2‐NC, p6pol‐PR, p1‐p6 and NC‐p1) to understand the structural and kinetic changes. The common drug‐resistant mutations V82A and I84V alter residues forming the substrate‐binding site. Eight crystal structures were refined at resolutions of 1.10–1.60 Å. Differences in the PR–analog interactions depended on the peptide sequence and were consistent with the relative inhibition. Analog p6pol‐PR formed more hydrogen bonds of P2 Asn with PR and fewer van der Waals contacts at P1′ Pro compared with those formed by CA‐p2 or p2‐NC in PR complexes. The P3 Gly in p1‐p6 provided fewer van der Waals contacts and hydrogen bonds at P2–P3 and more water‐mediated interactions. PRI84V showed reduced van der Waals interactions with inhibitor compared with PR, which was consistent with kinetic data. The structures suggest that the binding affinity for mutants is modulated by the conformational flexibility of the substrate analogs. The complexes of PRV82A showed smaller shifts of the main chain atoms of Ala82 relative to PR, but more movement of the peptide analog, compared to complexes with clinical inhibitors. PRV82A was able to compensate for the loss of interaction with inhibitor caused by mutation, in agreement with kinetic data, but substrate analogs have more flexibility than the drugs to accommodate the structural changes caused by mutation. Hence, these structures help to explain how HIV can develop drug resistance while retaining the ability of PR to hydrolyze natural substrates.
Protein database searches using compositionally adjusted substitution matrices
Authors: Altschul Stephen F. , Wootton John C. , Gertz E. Michael , Agarwala Richa , Morgulis Aleksandr , Schäffer Alejandro A. , Yu Yi‐Kuo
Published: October 2005

Almost all protein database search methods use amino acid substitution matrices for scoring, optimizing, and assessing the statistical significance of sequence alignments. Much care and effort has therefore gone into constructing substitution matrices, and the quality of search results can depend strongly upon the choice of the proper matrix. A long‐standing problem has been the comparison of sequences with biased amino acid compositions, for which standard substitution matrices are not optimal. To address this problem, we have recently developed a general procedure for transforming a standard matrix into one appropriate for the comparison of two sequences with arbitrary, and possibly differing compositions. Such adjusted matrices yield, on average, improved alignments and alignment scores when applied to the comparison of proteins with markedly biased compositions.

Here we review the application of compositionally adjusted matrices and consider whether they may also be applied fruitfully to general purpose protein sequence database searches, in which related sequence pairs do not necessarily have strong compositional biases. Although it is not advisable to apply compositional adjustment indiscriminately, we describe several simple criteria under which invoking such adjustment is on average beneficial. In a typical database search, at least one of these criteria is satisfied by over half the related sequence pairs. Compositional substitution matrix adjustment is now available in NCBI's protein–protein version of blast.
Utilizing logical relationships in genomic data to decipher cellular processes
Authors: Bowers Peter M. , O'Connor Brian D. , Cokus Shawn J. , Sprinzak Einat , Yeates Todd O. , Eisenberg David
Published: October 2005

The wealth of available genomic data has spawned a corresponding interest in computational methods that can impart biological meaning and context to these experiments. Traditional computational methods have drawn relationships between pairs of proteins or genes based on notions of equality or similarity between their patterns of occurrence or behavior. For example, two genes displaying similar variation in expression, over a number of experiments, may be predicted to be functionally related. We have introduced a natural extension of these approaches, instead identifying logical relationships involving triplets of proteins. Triplets provide for various discrete kinds of logic relationships, leading to detailed inferences about biological associations. For instance, a protein C might be encoded within an organism if, and only if, two other proteins A and B are also both encoded within the organism, thus suggesting that gene C is functionally related to genes A and B. The method has been applied fruitfully to both phylogenetic and microarray expression data, and has been used to associate logical combinations of protein activity with disease state phenotypes, revealing previously unknown ternary relationships among proteins, and illustrating the inherent complexities that arise in biological data.
Identifying remote protein homologs by network propagation
Authors: Noble William S. , Kuang Rui , Leslie Christina , Weston Jason
Published: October 2005

Perhaps the most widely used applications of bioinformatics are tools such as psi‐blast for searching sequence databases. We describe a recently developed protein database search algorithm called rankprop. rankprop relies upon a precomputed network of pairwise protein similarities. The algorithm performs a diffusion operation from a specified query protein across the protein similarity network. The resulting activation scores, assigned to each database protein, encode information about the global structure of the protein similarity network. This type of algorithm has a rich history in associationist psychology, artificial intelligence and web search. We describe the rankprop algorithm and its relatives, and we provide evidence that the algorithm successfully improves upon the rankings produced by psi‐blast.
Effects of rhythmic muscle compression on cardiovascular responses and muscle oxygenation at rest and during dynamic exercise
Authors: Nishiyasu Takeshi , Maekawa Tsuyoshi , Sone Ryoko , Tan Nobusuke , Kondo Narihiko
Published: October 2005

We examined the way in which the duration of rhythmic muscle compressions affects cardiovascular responses and muscle oxygenation at rest and during dynamic exercise. We measured the mean arterial pressure (MAP), heart rate (HR) and oxygenation of the vastus lateralis muscle (by near‐infrared spectroscopy) in eight healthy male subjects at rest and during supine bicycle exercise (50 and 100 W at 60 r.p.m.) while applying pulsed muscle compressions at 1000 ms intervals. Compression pressure and durations were 150 mmHg and 300, 600, 900 and 1000 ms (1000 ms being static continuous compression), respectively. During exercise, the pulsed leg compression was synchronized to each thigh extensor muscle contraction. The observed changes in muscle oxygenation were dependent on compression duration (increased at 300 ms, no change at 600 ms and decreased at 900 or 1000 ms) and were different from those seen at rest (increases at < 1000 ms and decrease at 1000 ms). This suggests that the effects of external pulsed muscle compression may have a duration threshold below which muscle pumping counteracts the obstruction to flow caused by the compression, and that the threshold is set at a shorter compression duration during exercise than at rest. Although HR and MAP did not change during pulsed compression at rest, during exercise they both increased progressively as compression duration increased. Thus, while exercising, the increased MAP and HR seen during the compression could be due to the combination and interaction of mechanical effects and the muscle mechanoreflex and/or metaboreflex.
The effect of changes in cardiac output on middle cerebral artery mean blood velocity at rest and during exercise
Authors: Ogoh Shigehiko , Brothers R. Matthew , Barnes Quinton , Eubank Wendy L. , Hawkins Megan N. , Purkayastha Sushmita , O‐Yurvati Albert , Raven Peter B.
Published: October 2005

We examined the relationship between changes in cardiac output and middle cerebral artery mean blood velocity (MCA Vmean) in seven healthy volunteer men at rest and during 50% maximal oxygen uptake steady‐state submaximal cycling exercise. Reductions in were accomplished using lower body negative pressure (LBNP), while increases in were accomplished using infusions of 25% human serum albumin. Heart rate (HR), arterial blood pressure and MCA Vmean were continuously recorded. At each stage of LBNP and albumin infusion was measured using an acetylene rebreathing technique. Arterial blood samples were analysed for partial pressure of carbon dioxide tension (P. During exercise HR and were increased above rest (P < 0.001), while neither MCA Vmean nor P was altered (P > 0.05). The MCA Vmean and were linearly related at rest (P < 0.001) and during exercise (P= 0.035). The slope of the regression relationship between MCA Vmean and at rest was greater (P= 0.035) than during exercise. In addition, the phase and gain between MCA Vmean and mean arterial pressure in the low frequency range were not altered from rest to exercise indicating that the cerebral autoregulation was maintained. These data suggest that the associated with the changes in central blood volume influence the MCA Vmean at rest and during exercise and its regulation is independent of cerebral autoregulation. It appears that the exercise induced sympathoexcitation and the change in the distribution of between the cerebral and the systemic circulation modifies the relationship between MCA Vmean and .
Exercise rapidly increases eukaryotic elongation factor 2 phosphorylation in skeletal muscle of men
Authors: Rose Adam J. , Broholm Christa , Kiillerich Kristian , Finn Stephen G. , Proud Christopher G. , Rider Mark H. , Richter Erik A. , Kiens Bente
Published: October 2005

Protein synthesis in skeletal muscle is known to decrease during contractions but the underlying regulatory mechanisms are unknown. Here, the effect of exercise on skeletal muscle eukaryotic elongation factor 2 (eEF2) phosphorylation, a key component in protein translation machinery, was examined. Eight healthy men exercised on a cycle ergometer at a workload eliciting ∼67% peak pulmonary oxygen consumption with skeletal muscle biopsies taken from the vastus lateralis muscle at rest as well as after 1, 10, 30, 60 and 90 min of exercise. In response to exercise, there was a rapid (i.e. < 1 min) 5‐ to 7‐fold increase in eEF2 phosphorylation at Thr56 that was sustained for 90 min of continuous exercise. The in vitro activity of skeletal muscle eEF2 kinase was not altered by exercise indicating that the increased activity of eEF2 kinase to eEF2 is not mediated by covalent mechanisms. In support of this, the increase in AMPK activity was temporally unrelated to eEF2 phosphorylation. However, skeletal muscle eEF2 kinase was potently activated by Ca2+–calmodulin in vitro, suggesting that the higher eEF2 phosphorylation in working skeletal muscle is mediated by allosteric activation of eEF2 kinase by Ca2+ signalling via calmodulin. Given that eEF2 phosphorylation inhibits eEF2 activity and mRNA translation, these findings suggest that the inhibition of protein synthesis in contracting skeletal muscle is due to the Ca2+‐induced stimulation of eEF2 kinase.
Spontaneous activity of lower urinary tract smooth muscles: correlation between ion channels and tissue function
Authors: Brading A. F.
Published: October 2005

Smooth muscles from the urethra and bladder display characteristic patterns of spontaneous contractile activity in the filling phase of the micturition cycle. Tonic contractions are seen in the urethral smooth muscles, and phasic contractions occur in the detrusor. Overactivity in the detrusor is a common clinical problem. The ion channels in the smooth muscle membranes play an important role in determining the functional properties, and are obvious targets for treatment of the overactive bladder. Recent evidence suggests that interstitial cells may also play a role in determining the pattern of spontaneous activity, although their precise role is less well established in the urinary tract than in the gut. The ion channels involved in these cells are also of interest. This review discusses what is known of ion channels in these tissues, and their implications for function.
Kv1 channels selectively prevent dendritic hyperexcitability in rat Purkinje cells
Authors: Khavandgar Simin , Walter Joy T. , Sageser Kristin , Khodakhah Kamran
Published: October 2005

Purkinje cells, the sole output of the cerebellar cortex, encode the timing signals required for motor coordination in their firing rate and activity pattern. Dendrites of Purkinje cells express a high density of P/Q‐type voltage‐gated calcium channels and fire dendritic calcium spikes. Here we show that dendritic subthreshold Kv1.2 subunit‐containing Kv1 potassium channels prevent generation of random spontaneous calcium spikes. With Kv1 channels blocked, dendritic calcium spikes drive bursts of somatic sodium spikes and prevent the cell from faithfully encoding motor timing signals. The selective dendritic function of Kv1 channels in Purkinje cells allows them to effectively suppress dendritic hyperexcitability without hindering the generation of somatic action potentials. Further, we show that Kv1 channels also contribute to dendritic integration of parallel fibre synaptic input. Kv1 channels are often targeted to soma and axon and the data presented support a major dendritic function for these channels.
The application of multi-array processors to underwater acoustics
Authors: Schultz Martin H.
Published: October 2005

Ocean acoustic problems are very complicated by nature and require large scale computations. Recent computer technology advances have produced very fast, inexpensive pipelined array processors. These processors allow the efficient, cost effective solution of complicated problems. This presentation begins with a demonstration of a two-dimensional model ocean acoustic long range propagation problem and discusses its solution on both a conventional sequential computer and a pipelined array processor. The next step of the application of multi-array processors is presented. A three-dimensional model ocean acoustics problem is chosen as a sample problem for such multiprocessors. [Work supported by ONR.]