bluuebunny/crossref_metadata_2025 huggingface dataset:
Recombinant nucleoprotein‐based serological diagnosis of Crimean–Congo hemorrhagic fever virus infections
Authors: Saijo Masayuki , Tang Qing , Shimayi Bawudong , Han Lei , Zhang Yuzhen , Asiguma Muer , Tianshu Dong , Maeda Akihiko , Kurane Ichiro , Morikawa Shigeru
Published: December 2004

An enzyme‐linked immunosorbent assay (ELISA) using recombinant nucleoprotein (rNP) was reported for the detection of immunoglobulin G (IgG) antibodies to Crimean–Congo hemorrhagic fever (CCHF) virus (CCHFV). The immunoglobulin M (IgM)‐capture ELISA was developed for the diagnosis of CCHFV infections, using CCHFV rNP as an antigen. These newly developed assays were applied to a study of a CCHF‐outbreak and evaluated with sera collected from patients diagnosed as having CCHF by positive reverse transcription‐polymerase chain reaction (RT‐PCR) and by detection of IgG response. IgM antibodies to CCHFV were detected in 10 of the 13 patients. IgM antibodies to the rNP of CCHFV were detected by the CCHFV rNP‐based IgM‐capture ELISA in all 6 patients in whom IgG responses were demonstrated, while it was not detected in the 10 patients in whom IgG responses were not demonstrated. Furthermore, the IgM antibodies were detected in 6 of the 61 residents living a CCHF endemic area during the endemic season, while it was not detected in any of the 48 Japanese residents that had never visited the CCHF endemic area. It is concluded that this newly developed CCHFV rNP‐based IgM‐capture ELISA is a useful method for the diagnosis of CCHFV infections. J. Med. Virol. 75:295–299, 2005. © 2004 Wiley‐Liss, Inc.
Experimental norovirus infections in non‐human primates
Authors: Rockx B.H.G. , Bogers W.M.J.M. , Heeney J.L. , van Amerongen G. , Koopmans M.P.G.
Published: December 2004

Noroviruses, with Norwalk virus as the prototype strain, are the most common cause of viral gastroenteritis in people of all ages. Limited information on the immunology of Norovirus infections has been obtained by studies both in the natural setting and in experimentally infected volunteers. Interpretation of these studies is difficult due to the lack of information on the history of Norovirus exposure and the cross‐reactivity of antibodies. An animal model for Norovirus infections would be important to study the immune response, e.g., for vaccine assessment. In the present study the susceptibility of common marmosets, cotton top tamarins, cynomolgus, and rhesus macaques to Norovirus infection was tested. Following oral inoculation, low level replication may have occurred in common marmosets and cotton top tamarins but not in cynomolgus macaques, based on short‐term viral shedding; neither clinical symptoms nor antibody responses were observed in these species. In contrast, rhesus macaques were found susceptible to Norwalk virus infection as one animal shed virus for a longer period of time and developed Norwalk virus specific IgM and IgG responses. Further research on Norovirus susceptibility in rhesus macaques may yield an animal model to study the immune response and pathogenesis after Norovirus infection. J. Med. Virol. 75:313–320, 2005. © 2004 Wiley‐Liss, Inc.
Reduced nasal IL‐10 and enhanced TNFα responses during rhinovirus and RSV‐induced upper respiratory tract infection in atopic and non‐atopic infants
Authors: van Benten I.J. , van Drunen C.M. , Koevoet J.L.M. , Koopman L.P. , Hop W.C.J. , Osterhaus A.D.M.E. , Neijens H.J. , Fokkens W.J.
Published: December 2004

Rhinovirus and respiratory syncytial virus (RSV) are the most prevalent inducers of upper respiratory tract infections (URTI) in infants and may stimulate immune maturation. To estimate the amount of immune stimulation, nasal immune responses were examined during rhinovirus and RSV‐induced URTI in infants. Nasal brush samples were taken from infants (2–26 months; 57% atopic family) with rhinovirus‐induced URTI (N = 20), with RSV‐induced URTI (N = 7), and with rhinovirus‐induced rhinitis (N = 11), from children with asymptomatic rhinovirus infection (N = 7) and from eight non‐infected children. Numbers of nasal brush cells positive for Th1‐, Th2‐, regulatory and proinflammatory cytokines were measured by immunohistochemistry or by measuring protein levels using a cytometric bead array analysis. During rhinovirus and RSV‐induced URTI, fewer regulatory cytokine IL‐10 positive cells were found compared to non‐infected children. This fall was accompanied by an increase in levels of the Th1 cytokine TNFα. IL‐10 responses were inversely related to TNFα responses. No enhanced responses were observed for IFNγ, IL‐12 and IL‐18. Cytokine responses were comparable in children with rhinovirus‐induced URTI and in children with rhinitis, while responses in asymptomatic rhinovirus‐infected children were located between those for symptomatic and asymptomatic rhinovirus‐infected children. Cytokine responses did not depend on the age of the child or atopy in the family. In conclusion, reduced nasal IL‐10 responses during URTI in infants could facilitate the induction of a TNFα response. TNFα in turn could replace the immature production of IL‐12, IL‐18 and IFNγ during URTI to induce an effective clearance of the viral infection and which could stimulate the maturation of Th1 cytokine production in infancy. J. Med. Virol. 75:348–357, 2005. © 2004 Wiley‐Liss, Inc.
Blood levels of TT virus following immune stimulation with influenza or hepatitis B vaccine
Authors: Maggi Fabrizio , Tempestini Elena , Lanini Letizia , Andreoli Elisabetta , Fornai Claudia , Giannecchini Simone , Vatteroni Marialinda , Pistello Mauro , Marchi Santino , Ciccorossi Pietro , Specter Steven , Bendinelli Mauro
Published: December 2004

Torque Teno virus (TTV) has been demonstrated to be present persistently in the blood of healthy individuals without evidence that it causes any disease process. The levels of TTV vary in patients co‐infected with other viruses and there has been considerable speculation as to whether TTV contributes to pathogenesis by other viruses or if the varying levels might be related to immune activation in the host. In the present study, the load of TTV was examined in plasma and peripheral blood mononuclear cells (PBMCs) following immunization of subjects with either influenza (a recall antigen) or hepatitis B virus (HBV) (a new antigenic exposure). The results overall did not indicate a significant change in TTV titers over a 90 day observation period; however, when TTV genogroup was taken into consideration there was an increase in viral load in plasma at some time points for subjects persistently infected with genogroup 3. While this was observed in both influenza and HBV immunized subjects, the effect was more profound in HBV vaccination. Thus, it appears that exposure to a new antigen rather than a recall antigen may stimulate TTV replication more effectively. The data further suggest that investigating the interactions between TTV and its host might require to examine specifically each TTV genogroup separately in order to determine if certain TTV types have any role in disease pathogenesis. J. Med. Virol. 75:358–365, 2005. © 2004 Wiley‐Liss, Inc.
Attenuation of acute inflammatory response by atorvastatin after spinal cord injury in rats
Authors: Pannu Ravinder , Barbosa Ernest , Singh Avtar K. , Singh Inderjit
Published: December 2004

Spinal cord injury (SCI) is a devastating and complex clinical condition involving proinflammatory cytokines and nitric oxide toxicity that produces a predictable pattern of progressive injury entailing neuronal loss, axonal destruction, and demyelination at the site of impact. The involvement of proinflammatory cytokines and inducible nitric oxide synthase (iNOS) in exacerbation of SCI pathology is well documented. We have reported previously the antiinflammatory properties and immunomodulatory activities of statins (3‐hydroxy‐3‐methylglutaryl [HMG]‐CoA reductase inhibitors) in the animal model of multiple sclerosis, experimental allergic encephalitis (EAE). The present study was undertaken to investigate the efficacy of atorvastatin (Lipitor; LP) treatment in attenuating SCI‐induced pathology. Immunohistochemical detection and real‐time PCR analysis showed increased expression of iNOS, tumor necrosis factor α (TNFα) and interleukin 1β (IL‐1β) after SCI. In addition, neuronal apoptosis was detected 24 hr after injury followed by a profound increase in ED1‐positive inflammatory infiltrates, glial fibrillary acidic protein (GFAP)‐positive reactive astrocytes, and oligodendrocyte apoptosis by 1 week after SCI relative to control. LP treatment attenuated the SCI‐induced iNOS, TNFα, and IL‐1β expression. LP also provided protection against SCI‐induced tissue necrosis, neuronal and oligodendrocyte apoptosis, demyelination, and reactive gliosis. Furthermore, rats treated with LP scored much higher on the locomotor rating scale after SCI (19.13 ± 0.53) than did untreated rats (9.04 ± 1.22). This study therefore reports the beneficial effect of atorvastatin for the treatment of SCI‐related pathology and disability. © 2004 Wiley‐Liss, Inc.
Spatial and temporal patterns of growth and differentiation of cone oil droplets in the chick retina
Authors: López Rosario , López‐Gallardo Meritxell , Busturia Ignacio , Anezary Lyazed , Prada Carmen
Published: December 2004

Avian cone photoreceptors have an oil droplet in the outer portion of their inner segment that acts as a long‐pass cut‐off filter between incident light and visual pigment. Chick cone droplets are mainly red, orange, yellow, green, and colorless, and the colors are due to three carotenoid pigments with characteristic absorption spectra. Little is known of the differentiation of this organelle, the natural marker of cones, and the little that is known is largely controversial. We used flat whole‐mounts of fresh retinas to study the time and place of the appearance of droplets, their growth rates, the sequence of droplet color differentiation, and the spatial distribution of these colors. We show that droplet differentiation starts on embryonic Day 10 (E10) in a relatively small area above the optic nerve head. The differentiation spreads to the rest of the retina in a manner similar to that of photoreceptor neurogenesis, with three decreasing gradients of droplet size and color between E13–E20: from central to peripheral, dorsal to ventral, and temporal to nasal. The rate of growth of the droplets was not constant, but showed a maximum between E17 and postnatal Day 1 (P1) in most of the retinal zones. Color differentiation started at E16–E17, 5–6 days after their appearance, when the droplets were already of considerable size. Initially, all droplets were colorless, and then turned pale green or yellow to acquire progressively the mature colors. Differentiation ended in the whole retina by P15, with ventral droplets of larger diameter than dorsal ones, the peripheral ones generally larger than the central ones, and with the color distribution varying with the retinal area. Our results show that growth and color differentiation of the droplets is regulated temporally and spatially, and the cones complete differentiation at P15 rather than at prenatal stages, as is thought generally. © 2004 Wiley‐Liss, Inc.
Rate coefficients for the gas‐phase reaction of isoprene with NO3 and NO2
Authors: Stabel Jeanette R. , Johnson Matthew S. , Langer Sarka
Published: December 2004

Rate coefficients for the gas‐phase reaction of isoprene with nitrate radicals and with nitrogen dioxide were determined. A Teflon collapsible chamber with solid phase micro extraction (SPME) for sampling and gas chromatography with flame ionization detection (GC/FID) and a glass reactor with long‐path FTIR spectroscopy were used to study the NO3 radical reaction using the relative rate technique with trans‐2‐butene and 2‐buten‐1‐ol (crotyl alcohol) as reference compounds. The rate coefficients obtained are k(isoprene + NO3) = (5.3 ± 0.2) × 10−13 and k(isoprene + NO3) = (7.3 ± 0.9) × 10−13 for the reference compounds trans‐2‐butene and 2‐buten‐1‐ol, respectively.

The NO2 reaction was studied using the glass reactor and FTIR spectroscopy under pseudo‐first‐order reaction conditions with both isoprene and NO2 in excess over the other reactant. The obtained rate coefficient was k(isoprene + NO2) = (1.15 ± 0.08) × 10−19. The apparent rate coefficient for the isoprene and NO2 reaction in air when NO2 decay was followed was (1.5 ± 0.2) × 10−19. The discrepancy is explained by the fast formation of peroxy nitrates. Nitro‐ and nitrito‐substituted isoprene and isoprene‐peroxynitrate were tentatively identified products from this reaction.

All experiments were conducted at room temperature and at atmospheric pressure in nitrogen or synthetic air. All rate coefficients are in units of cm3 molecule−1 s−1, and the errors are three standard deviations from a linear least square analyses of the experimental data. © 2004 Wiley Periodicals, Inc. Int J Chem Kinet 37: 57–65, 2005
Direct measurements of the reaction OH + CH2O → HCO + H2O at high temperatures
Authors: Vasudevan Venkatesh , Davidson David F. , Hanson Ronald K.
Published: December 2004

The reaction of hydroxyl [OH] radicals with formaldehyde [CH2O] was studied at temperatures ranging from 934 K to 1670 K behind reflected shock waves at an average total pressure of 1.6 atm. OH radicals were produced by shock‐heating tert‐butyl hydroperoxide [(CH3)3COOH], while 1,3,5‐trioxane [(CH2O)3] was used in the preshock mixtures to generate reproducible levels of CH2O. OH concentration time‐histories were inferred from laser absorption using the well‐characterized R1(5) line of the OH A‐X (0, 0) band near 306.7 nm. Detailed error analyses, taking into account both experimental and mechanism‐induced contributions, yielded uncertainty estimates of ±25% at 1595 K and ±15% at 1229 K for the rate of the reaction between CH2O and OH. These uncertainties are substantially lower than the factor of two uncertainty currently used for this reaction at high temperatures. The rate constants were fit with the recent low‐temperature measurements of Sivakumaran et al. (Phys Chem Chem Phys 2003,5,4821–4827) to the three‐parameter form shown below; this fit reconciles experimental data on the title reaction at low, intermediate, and high temperatures (200–1670 K).

equation image

The reaction of OH with CH2O was also studied using quantum chemical methods at the CCSD(T) level of theory using the 6‐311 ++ G(d,p) basis set. The transition state for the H‐atom metathesis reaction was located, and reaction rate coefficients were calculated. Reasonable agreement with the experimental measurements was obtained.

The decomposition rate of tert‐butyl hydroperoxide to a tert‐butoxy radical and an OH radical was measured, and fit to the following form

equation image

Uncertainty limits for k5 were estimated to be ±25% in the 900–1000 K temperature range, a marked reduction from the factor of 2–3 uncertainty currently recommended for this reaction in the literature. © 2004 Wiley Periodicals, Inc. Int J Chem Kinet 37: 98–109, 2005
Whip–PIFA combination for handset application: A hybrid circuit model and full‐wave analysis
Authors: Li Zhan , Rahmat‐Samii Yahya
Published: December 2004

In this paper, a circuit model is developed in RF ADS in order to simulate the coupling effect of a retracted whip on a planar inverted‐F antenna (PIFA) for wireless‐handset application. The PIFA is designed as the main antenna of the handset to cover the 800‐MHz (824–894 MHz) and 1900‐MHz (1850–1990 MHz) bands. A parasitic whip antenna is used to improve the performance of the PIFA, especially when the handset is used against the human head. In such a whip–PIFA combination environment, the retracted whip will degrade the PIFA performance if it is not designed carefully. The purpose of this paper is to present an efficient method to optimize the PIFA performance when the whip antenna is in the retracted position. © 2005 Wiley Periodicals, Inc. Microwave Opt Technol Lett 44: 210–215, 2005; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.20590
Temporal acceleration of time‐domain integral‐equation solvers for electromagnetic scattering from objects residing in lossy media
Authors: Jiang Pei‐Lin , Michielssen Eric
Published: December 2004

The computational cost and memory requirements of classical marching‐on‐in‐time (MOT)‐based time‐domain integral‐equation (TDIE) solvers for analyzing scattering of electromagnetic waves from surfaces residing in lossy media scale asO(NN) andO(NNt), respectively; here,NsandNtare the number of spatial and temporal degrees of freedom of the surface currents. The quadratic dependency of these costs uponNsandNtprevents these methods from being applied to the analysis of large‐scale scattering phenomena. Here, an accelerator is proposed to improve the scaling of these TDIE solvers' computational complexity and memory requirements withNt. The accelerator casts temporal tails in convolutions of the lossy medium‐wave‐equation Green's function and TDIE solver temporal‐current basis functions in terms of a Prony series. This representation enables computation of the fields produced by surface currents within an MOT framework via recursive convolution. A technique that allows the reuse of Prony series poles for extended spatial interaction ranges, thereby greatly enhancing the scheme's efficacy, is proffered. The scheme's computational cost and memory requirements scale asO(NNtlogNt) andO(NlogNt), respectively, with fairly small multiplicative factors. Besides being useful in the analysis of scattering from electromagnetically small objects residing in lossy backgrounds, the proposed scheme also constitutes a key building block in the construction of improved lossy‐medium plane‐wave time‐domain algorithms with efficient near‐field evaluation capability. © 2005 Wiley Periodicals, Inc. Microwave Opt Technol Lett 44: 223–230, 2005; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.20595
8‐GHz bandwidth spatial‐sampling modules for ultra‐fast random‐signal analysis
Authors: Rolland Nathalie , Benlarbi‐Delaï Aziz , Ghis Anne , Rolland Paul‐Alain
Published: December 2004

The design of a novel large bandwidth random‐signal analyzer with 20‐Gs/s sampling frequency and 60‐dB dynamic range is discussed. Using the principle of nonsimultaneous spatial sampling, its realization, led through several 0.18‐μm GaAs PHEMT MMIC, authorizes the microwave characterization of a first demonstrator, which allows a temporal analysis depth of 1.2 ns and a risetime as fast as 20 ps. © 2005 Wiley Periodicals, Inc. Microwave Opt Technol Lett 44: 292–295, 2005; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.20614
1.8‐V 3.1–10.6‐GHz CMOS low‐noise amplifier for ultra‐wideband applications
Authors: Lu Yang , Yeo Kiat Seng , Ma Jian Guo , Do Manh Anh , Lu Zhenghao
Published: December 2004

A novel CMOS low‐noise amplifier (LNA) for 3.1–10.6‐GHz ultra‐wideband (UWB) applications is presented in this paper. As opposed to most of the previously reported UWB LNAs, which are based on SiGe technology, the proposed UWB LNA is designed based on chartered semiconductor manufacturing (CSM) 0.18‐μm 1.8‐V standard RFCMOS technology. The prelayout and post‐layout circuit simulation results show that low noise figure, good input and output matching, a relatively flat gain in the 3.1–10.6‐GHz UWB band, and low power consumption features are all achieved in the proposed CMOS UWB LNA. © 2005 Wiley Periodicals, Inc. Microwave Opt Technol Lett 44: 299–302, 2005; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.20616
Relationship between urinary symptoms reported in a postal questionnaire and urodynamic diagnosis
Authors: Matharu G. , Donaldson M.M.K. , McGrother C.W. , Matthews R.J.
Published: December 2004

Aims

To describe the relationship between symptoms reported in a self‐completed postal questionnaire and urinary disorders based on urodynamic investigation.

Methods

The study population was selected from women aged 40 years or over living in the community, who responded to a postal questionnaire. Following assessment and appropriate conservative interventions, those with a pre‐defined level of severity of symptoms were offered urodynamic investigation. Logistic regression examined the association between urinary symptoms and the urodynamic diagnoses of detrusor overactivity (DO) and urodynamic stress incontinence (USI).

Results

Four hundred eighty‐eight women completed urodynamic investigation; 29.1% (142/488) were found to have DO, 33.6% (164/488) USI, 20.7% (101/488) mixed incontinence, and 16.6% (81/488) no urodynamic abnormality. Stress incontinence (SI) and urge incontinence (UI) were included in the risk model for USI. SI reported monthly or more was associated with increased risk of USI, and UI reported weekly or more with decreased risk (sensitivity 76.9%; specificity 56.3%; positive predictive value (PPV) 67.8%). For DO, strong or overwhelming urgency, UI monthly or more, and nocturia once a night or more were all significantly associated with an increased risk while reporting of SUI monthly or more reduced the risk (sensitivity 63.1%; specificity 65.1%; PPV 63.1%).

Conclusions

Urinary symptoms reported in a postal questionnaire are able to predict urodynamic diagnoses with moderate accuracy. These models may be useful tools with which to categorize urinary disorders for epidemiological study and, with further development, allocate first line treatment. © 2004 Wiley‐Liss, Inc.
The effect of mean stress on damage predictions for spectral loading of fibreglass composite coupons
Authors: Sutherland Herbert J. , Mandell John F.
Published: December 2004

In many analyses of wind turbine blades the effects of mean stress on the determination of damage in composite blades are either ignored completely or characterized inadequately. Mandell et al. have recently presented an updated Goodman diagram for a fibreglass material that is typical of the materials used in wind turbine blades. Their formulation uses the MSU/DOE fatigue database to develop a Goodman diagram with detailed information at 13 R‐values. Using these data, linear, bilinear and full Goodman diagrams are constructed using mean and ‘95/95’ fits to the data. The various Goodman diagrams are used to predict the failure stress for coupons tested using the WISPERX spectrum. Three models are used in the analyses. The first is the linear Miner's rule commonly used by the wind industry to predict failure (service lifetimes). The second is a non‐linear variation of Miner's rule which computes a non‐linear Miner's residual strength based upon an exponential degradation parameter. The third is a generalized non‐linear residual strength model that also relies on an exponential degradation parameter. The results illustrate that Miner's rule does not predict failure very well. When the mean full Goodman diagram is used, the non‐linear models predict failures near the mean of the experimental data, and when the 95/95 Goodman diagram is used, they predict the lower bound of the measured data very well. Published in 2004 by John Wiley & Sons, Ltd.
Seismic analysis of wind turbines in the time domain
Authors: Witcher D.
Published: December 2004

The analysis of wind turbine loading associated with earthquakes is clearly important when designing for and assessing the feasibility of wind farms in seismically active regions. The approach taken for such analysis is generally based on codified methods which have been developed for the assessment of seismic loads acting on buildings. These methods are not able to deal properly with the aeroelastic interaction of the dynamic motion of the wind turbine structure with either the wind loading acting on the rotor blades or the response of the turbine controller. This article presents an alternative approach, which is to undertake the calculation in the time domain. In this case a full aeroelastic model of the wind turbine subject to turbulent wind loading is further excited by ground motion corresponding to the earthquake. This capability has been introduced to the GH Bladed wind turbine simulation package. The software can be used to compute the combined wind and earthquake loading of a wind turbine given a definition of the external conditions for an appropriate series of load cases. This article discusses the method and presents example results. Copyright © 2004 John Wiley & Sons, Ltd.
Active load reduction using individual pitch, based on local blade flow measurements
Authors: Larsen Torben Juul , Madsen Helge A. , Thomsen Kenneth
Published: December 2004

A new load‐reducing control strategy for individual blade control of large pitch‐controlled wind turbines is presented. This control concept is based on local blade inflow measurements and offers the possibility of larger load reductions, without loss of power production, than seen in other state‐of‐the‐art load‐reducing concepts. Since the new flow‐based concept deviates significantly from previous published load‐reducing strategies, a comparison of the performance based on aeroelastic simulations is included. Advantages and drawbacks of the systems are discussed. Copyright © 2004 John Wiley & Sons, Ltd.
Brief report: Labelling effects on the perceived deleterious consequences of pop music listening
Authors: North Adrian C. , Hargreaves David J.
Published: December 2004

Several correlational studies have supported the claim of conservative protestors that there exists a positive relationship between listening to pop music and adolescent problem behaviours. However, research on the so‐called ‘prestige effects’ has shown that experimental participants’ responses to music can be mediated by manipulations of prior information concerning that music. This study investigated whether perceptions of deleterious effects of pop songs on listeners may be attributable to prior labelling of those stimuli as ‘problem music’. Eighty undergraduates were played songs that they were told were either suicide‐inducing or life‐affirming. Subsequent ratings of the songs indicated that those presented as ‘suicide‐inducing’ were perceived as such, whereas presentation of the same songs in a ‘life‐affirming’ frame led to the perception of them as such. These findings indicate that censorship and the subsequent labelling of certain songs as ‘problematic’ might itself cause these songs to have deleterious effects on listeners.
Effect of TNF‐α on human osteosarcoma cell line Saos2—TNF‐α regulation of bone sialoprotein gene expression in Saos2 osteoblast‐like cells
Authors: Nakayama Youhei , Kato Naoko , Nakajima Yu , Shimizu Emi , Ogata Yorimasa
Published: December 2004

Tumor necrosis factor‐alpha (TNF‐α) is a major mediator of inflammatory response in many diseases. It inhibits bone formation and stimulates bone resorption. To determine the molecular mechanisms involved in the regulation of gene expression of osteoblast‐like cells, we analyzed the effects of TNF‐α on the human osteosarcoma cell line Saos2. We used RT‐PCR to examine the effects of TNF‐α on bone sialoprotein (BSP), core binding factor a1 (Cbfa1), osterix, α1 (I) collagen, cyclooxygenase‐2 (COX‐2), interleukin‐6 (IL‐6), cathepsin B, cathepsin L and tissue inhibitors of metalloproteinase‐1 (TIMP‐1). TNF‐α (10 ng/ml) increased BSP, IL‐6 and COX‐2 mRNA levels after 3 h, reaching maximal levels at 12 h. Cbfa1 mRNA levels increased after 3 h, but decreased by 24 h. Osterix, cathepsin B, cathepsin L and TIMP‐1 mRNA levels did not change after stimulation with TNF‐α. On the other hand, α1 (I) collagen mRNA expression was suppressed by TNF‐α at 24 h.

Transient transfection analyses were performed using chimeric constructs of the rat BSP gene promoter linked to a luciferase reporter gene. TNF‐α (10 ng/ml) had no effect on the promoter activities of BSP transfected into Saos2 cells. The results of gel mobility shift assays using radiolabeled double‐stranded cAMP response element (CRE) and FGF2 response element (FRE) oligonucleotides in the proximal promoter of the rat BSP gene showed increased binding of nuclear proteins at 6 h. Gel mobility shift assays with radiolabelled COX‐2‐CRE and COX‐2‐NFκB oligonucleotides revealed an increase in the binding of nuclear proteins from TNF‐α‐stimulated Saos2 cells. These studies, therefore, showed that TNF‐α indirectly increased BSP expression, and that it could be mediated through COX‐2 and Cbfa1 expression in Saos2 osteoblast‐like cells.
Kinetics of Smac/DIABLO release from mitochondria during apoptosis of MCF‐7 breast cancer cells
Authors: Gorka Magdalena , Godlewski Michal Marek , Gajkowska Barbara , Wojewodzka Urszula , Motyl Tomasz
Published: December 2004

Smac/DIABLO, a pro‐apoptotic protein released from mitochondrial intermembrane space during apoptosis, promotes caspase activation by IAPs neutralization. The kinetics and molecular mechanism of Smac/DIABLO release from mitochondria has remained obscure. Homeostatic confocal microscopy, for the first time, showed the precise kinetics of Smac/DIABLO release from mitochondria during CPT‐induced apoptosis in living MCF‐7 cells. The time pattern of Smac/DIABLO escape from mitochondria comprised two phases: the initial phase of gradual protein release, followed by the second phase of plateau, appearing after 24 min of cell exposure to the drug. A similar pattern was observed during oxidative stress. The dynamics of Smac/DIABLO redistribution was confirmed by different methods: traditional confocal microscopy, immunoelectron microscopy and laser scanning cytometry. The inhibition of m‐calpain prevented Smac/DIABLO release from mitochondria, which confirmed the involvement of Bax in the process. Acquired results indicate that CPT treatment triggers Bax‐dependent release of Smac/DIABLO from mitochondria simultaneously with the efflux of cytochrome c.
Plasticity of rat bone marrow‐derived 5‐hydroxytryptamine‐sensitive neurons: dedifferentiation and redifferentiation
Authors: Li Ting Yu , Shu Chang , Wong Connie Hau Yan , Lo Pui Shan , Zhu Hu , Lau Miu Ching , Chan Man Yi , Tsang Lai Ling , Gou Yu Lin , Chung Yiu Wa , Chan Hsiao Chang
Published: December 2004

Inducing cellular dedifferentiation has been proposed as a potential method for enhancing endogenous regeneration in mammals. Here we demonstrate that phenotypic and functional neurons derived from adult rat bone marrow stromal stem cells (MSCs) can be induced to undergo dedifferentiation, then proliferation and redifferentiation. In addition to morphological changes and expression of neuronal markers, neuron‐specific enolase and neurofilament H, functional differentiation was monitored by intracellular Ca2+ mobilization in response to a ubiquitous neurotransmitter, 5‐hydroxytryptamine (5‐HT) at different stages. The neurons derived from rMSCs were found to have increased 5‐HT response. This 5‐HT sensitivity could be reversed to basal level similar to that found in rMSCs when neurons, up to 3 days after neuronal induction, were induced to undergo dedifferentiation. Increase in 5‐HT‐induced Ca2+ mobilization was again observed when rMSCs derived from dedifferentiated neurons were induced to redifferentiate into neurons again. Variation in 5‐HT1A receptor immunoreactivity was observed in stem cells, differentiated neurons, dedifferentiated neurons and redifferentiation neurons, consistent with their respective 5‐HT sensitivity. These results suggest that adult bone marrow‐derived 5‐HT sensitive neurons are capable of dedifferentiation, then proliferation and redifferentiation, indicating their plasticity and potential use in treatment of neural degenerative diseases.
Connective tissue growth factor regulates the key events in tubular epithelial to myofibroblast transition in vitro
Authors: Zhang Chun , Meng Xianfang , Zhu Zhonghua , Liu Jianshe , Deng Anguo
Published: December 2004

Connective tissue growth factor (CTGF) has been reported to play an important role in mediating the profibrotic effects of transforming growth factor‐β (TGF‐β) in various renal diseases. To elucidate the role of CTGF in renal tubular epithelial‐myofibroblast transdifferentiation, we examined the expression of α‐smooth muscle actin (α‐SMA), vimentin, tenascin‐C, and collagen IV expression upon the stimulation of CTGF in cultured human proximal tubular epithelial cell line (HKC), and further investigated the effects of endogenous CTGF blockade on the transdifferentiation process induced by TGF‐β. It is revealed that upon the stimulation of recombinant human CTGF (rhCTGF, 2.5 or 5.0 μg/L), the expression of α‐SMA and tenascin‐C mRNA increased significantly (p < 0.01), while collagen IV gene expression decreased significantly (p < 0.01), all in a dose‐dependent manner. The percentage of α‐SMA‐positive cells was significantly larger in the rhCTGF‐stimulated groups than that in negative control (38.9%, 65.5% vs. 2.4%, respectively, p < 0.01) as confirmed by flow cytometry. Both cytoplasmic and secretory tenascin‐C expression was upregulated by the stimulation of rhCTGF (p < 0.01). Under this condition, collagen IV secreted into the culture media was lowered markedly (p < 0.01). On RT‐PCR analysis, TGF‐β1 upregulated CTGF gene expression, preceding that of α‐SMA. The α‐SMA mRNA expression induced by TGF‐β1 was significantly inhibited by CTGF antisense oligodeoxynucleotide (ODN) transfection (p < 0.01). With prolonged incubation time, CTGF antisense ODN also inhibited intracellular α‐SMA protein synthesis, as demonstrated by indirect immuno‐fluorescence. So it is concluded that CTGF could promote the transdifferentiation of human renal tubular epithelial cells towards myofibroblasts in vitro, both directly and as a downstream mediator of TGF‐β, and CTGF blockade would be a possible therapeutic target against tubulointerstitial fibrosis.
Tissue Doppler velocities of mitral annulus and NT‐proBNP in patients with heart failure
Authors: Tretjak Martin , Verovnik Franc , Benko Davorin , Kozelj Mirta
Published: December 2004

Background

It has been shown that pulsed wave tissue Doppler velocities of mitral annulus correlate well with left ventricular (LV) diastolic and systolic functions. It is not yet clear whether these velocities can be used to estimate left ventricular dysfunction in an unselected population of patients with clinical signs and symptoms of heart failure (HF).

Aim

To determine whether LV mitral annulus velocities measured by tissue Doppler imaging (TDI) correlate with plasma N‐terminal pro‐brain natriuretic peptide (NT‐proBNP) levels in patients with HF.

Methods and results

Early diastolic (Em) and systolic (Sm) TDI velocities of septal and lateral mitral annulus were measured in 50 patients with HF together with other conventional echocardiographic parameters, and compared with plasma NT‐proBNP levels. Significant correlations were found between NT‐proBNP level and Em velocity (r=−0.79), Sm velocity (r=−0.43), early transmitral to Em velocity ratio (r=0.38), LV end diastolic diameter (r=0.29), LV ejection fraction (r=−0.44) and tricuspid regurgitant velocity (r=0.31). In multiple regression model (R2=0.733), the Em velocity was the most important predictor of NT‐proBNP level.

Conclusions

Early diastolic mitral annulus velocity measured by TDI correlates strongly with plasma NT‐proBNP levels, and provides a simple, accurate and reproducible echocardiographic index of heart failure.
Comparison of selective ETA and ETB receptor antagonists in patients with chronic heart failure
Authors: Cowburn Peter J. , Cleland John G.F. , McDonagh Theresa A. , McArthur John D. , Dargie Henry J. , Morton James J.
Published: December 2004

Background

The vasoconstrictor action of endothelin‐1 (ET‐1) is mediated through ETA and ETB receptor subtypes on vascular smooth muscle. ETB receptors are also present on the vascular endothelium where they mediate vasodilation. Animal studies suggest that the ETB receptor also acts as a clearance receptor for endothelin.

Aims

To investigate the effects of a selective ETA and a selective ETB receptor antagonist alone and in combination on haemodynamics and circulating concentrations of ET‐1 in patients with chronic heart failure.

Results

Infusion of BQ‐123 (n=10), a selective ETA receptor antagonist, led to systemic vasodilation and did not change plasma ET‐1 concentrations (1.38±0.82 to 1.38±0.91 fmol/ml, ns). Infusion of BQ‐788 (n=8) led to systemic vasoconstriction with a rise in plasma ET‐1 (1.84±1.06 to 2.73±0.99 fmol/ml, p<0.01). The addition of BQ‐123 to BQ‐788 led to systemic and pulmonary vasodilation with no further increase in plasma ET‐1 concentrations (2.80±1.14 to 2.90±1.20 fmol/ml, ns).

Conclusion

The rise in plasma ET‐1 concentrations in response to selective blockade of ETB receptors and the associated adverse haemodynamic effects suggest that ETB receptors have a role in the clearance of ET‐1 in man and that their blockade may not be advantageous for patients with heart failure.
Effects of lycorine on HL‐60 cells via arresting cell cycle and inducing apoptosis
Authors: Liu Jing , Hu Wei-Xin , He Li-Fang , Ye Mao , Li Yan
Published: December 2004

As a natural anti‐cancer alkaloid extracted from Amaryllidaceae, lycorine shows various biological effects on tumor cells. The survival rate of HL‐60 cells exposed to lycorine was decreased in a dose‐dependent manner with 1 μM as the 50% inhibitory concentration (IC50), cell growth was slowed down by arresting cell cycle at G2/M phase, and cell regeneration potential was inhibited. HL‐60 cells exhibited typical apoptotic morphological changes, apoptotic DNA “ladder” pattern, and sub‐G1 peak in cell phase distribution, showing apoptosis of HL‐60 cells. To further understand the apoptotic molecular mechanism of lycorine on HL‐60 cells, caspase activity was tested by colorimetric assay, and the expression of Bcl‐2 and Bax proteins was examined by Western blotting. The increase of caspase‐8, ‐9, ‐3 activities demonstrated that caspase was a key mediator of apoptotic pathways induced by lycorine. Under‐expression of Bcl‐2 and increase of Bax:Bcl‐2 ratio showed that Bcl‐2 family proteins were involved in apoptosis. Our finding suggests that lycorine can suppress leukemia growth and reduce cell survival via arresting cell cycle and inducing apoptosis of tumor cells.
Antigen binding and stability properties of non‐covalently linked anti‐CD22 single‐chain Fv dimers
Authors: Arndt Michaela A.E. , Krauss Jürgen , Rybak Susanna M.
Published: December 2004

By varying linker length and domain orientation three multivalent derivatives of a monovalent anti‐CD22 single‐chain fragment variable (scFv) antibody were generated. Shortening the linker of the VH–VL oriented scFv to 5 or 0 residues resulted in the formation of diabodies or a mixture of tetramers and trimers, respectively. Unexpectedly, a VL–0–VH scFv assembled to homogenous dimers, remained substantially more stable than the VH–5–VL diabody when incubated in human serum at 37 °C, and retained its dimeric state when concentrated up to 4 mg/ml. These properties suggest the VL–0–VH scFv could become an attractive vehicle for the selective delivery of multiple effector molecules to CD22+ tumor cells.
Interactions of putative telomere‐binding proteins in Arabidopsis thaliana: identification of functional TRF2 homolog in plants
Authors: Kuchař Milan , Fajkus Jiří
Published: December 2004

Telomere‐binding proteins are required for forming the functional structure of chromosome ends and regulating telomerase action. Although a number of candidate proteins have been identified by homology searches to plant genome databases and tested for their affinity to telomeric DNA sequences in vitro, there are minimal data relevant to their telomeric function. To address this problem, we made a collection of cDNAs of putative telomere‐binding proteins of Arabidopsis thaliana to analyse their protein–protein interactions with the yeast two‐hybrid system. Our results show that one myb‐like protein, AtTRP1, interacts specifically with AtKu70, the latter protein having a previously described role in plant telomere metabolism. In analogy to the interaction between human Ku70 and TRF2 proteins, our results suggest that AtTRP1 is a likely homolog of TRF2. The AtTRP1 domain responsible for AtKu70 interaction occurs between amino acid sequence positions 80 and 269. The protein AtTRB1, a member of the single myb histone (Smh) family, shows self‐interaction and interactions to the Smh family proteins AtTRB2 and AtTRB3. Protein AtTRB1 also interacts with AtPot1, the Arabidopsis homolog of oligonucleotide‐binding‐fold‐containing proteins which bind G‐rich telomeric DNA. In humans, the TRF1‐complex recruits hPot1 to telomeres by protein–protein interactions where it is involved in telomere length regulation. Possibly, AtTRB1 has a similar role in recruiting AtPot1.
Identification of a hTid‐1 mutation which sensitizes gliomas to apoptosis
Authors: Trentin G.A. , He Y. , Wu D.C. , Tang D. , Rozakis-Adcock M.
Published: December 2004

Human Tid‐1 (hTid‐1) is a DnaJ chaperone protein with homology to the Drosophila tumor suppressor Tid56. We report the first case of a tumor‐associated mutation at the human TID1 locus, which was identified in the SF767 glioma cell line giving rise to aberrantly high levels of a hTid‐1L mutant variant. In this study, we set out to determine whether this change in hTid‐1 status influences the response of glioma cells to adenoviral (Ad)‐mediated delivery of the two major isoforms of TID1, hTid‐1L and hTid‐1S. Ad‐hTid‐1S induced apoptosis in hTid‐1 mutant SF767 cells, while causing growth arrest in wild‐type hTid‐1‐expressing U373 and U87 cells. By contrast, Ad‐hTid‐1L infection had no apparent effect on glioma cell growth. The apoptosis induced by hTid‐1S was accompanied by mitochondrial cytochrome C release and caspase activation and blocked by stable overexpression of Bcl‐XL. Our findings suggest that the status of hTid‐1 in gliomas may contribute to their susceptibility to cell death triggers.
Portraits of a Y‐family DNA polymerase
Authors: Yang Wei
Published: December 2004

Members of the Y‐family of DNA polymerases catalyze template‐dependent DNA synthesis but share no sequence homology with other known DNA polymerases. Y‐family polymerases exhibit high error rates and low processivity when copying normal DNA but are able to synthesize DNA opposite damaged templates. In the past three years, much has been learned about this family of polymerases including determination of more than a dozen crystal structures with various substrates. In this short review, I will summarize the biochemical properties and structural features of Y‐family DNA polymerases.
Solubilization of aggregated proteins by ClpB/DnaK relies on the continuous extraction of unfolded polypeptides
Authors: Schlieker Christian , Tews Ivo , Bukau Bernd , Mogk Axel
Published: December 2004

The AAA+ chaperone ClpB solubilizes in cooperation with the DnaK chaperone system aggregated proteins. The mechanistic features of the protein disaggregation process are poorly understood. Here, we investigated the mechanism of ClpB/DnaK‐dependent solubilization of heat‐aggregated malate dehydrogenase (MDH) by following characteristics of MDH aggregates during the disaggregation reaction. We demonstrate that disaggregation is achieved by the continuous extraction of unfolded MDH molecules and not by fragmentation of large MDH aggregates. These findings support a ClpB‐dependent threading mechanism as an integral part of the disaggregation reaction.
Efavirenz enhances the proteolytic processing of an HIV‐1 pol polyprotein precursor and reverse transcriptase homodimer formation
Authors: Tachedjian Gilda , Moore Katie L. , Goff Stephen P. , Sluis-Cremer Nicolas
Published: December 2004

The non‐nucleoside reverse transcriptase inhibitor, efavirenz (EFV), is a potent enhancer of human immunodeficiency virus type 1 (HIV‐1) reverse transcriptase (RT) p66/p51 heterodimerization. While the mechanism of RT heterodimer formation in HIV‐1 infected cells is not completely understood, it has been speculated that Gag–Pol/Gag–Pol and/or RT homodimer interactions may represent important intermediates in the pathway. To elucidate whether EFV impacts on these interactions, we have evaluated the effects of this drug on RT homodimer interactions and HIV‐1 Gag–Pol processing. EFV, but not nevirapine, significantly enhanced RT p66/p66 and p51/p51 homodimer interactions and accelerated the proteolytic cleavage of a model HIV‐1 Pol polyprotein precursor expressed in bacteria. These data suggest that potent mediators of RT dimerization might interfere with the late‐stages of viral replication.
Chokka squid (Loligo vulgaris reynaudii) abundance linked to changes in South Africa's Agulhas Bank ecosystem during spawning and the early life cycle
Authors: Roberts Michael J.
Published: December 2004

Chokka squid biomass and catch are highly variable, likely owing to their links to changes in the ecosystem, which impact spawning and recruitment. A synthesis of basic ecosystem components for the domain in which chokka squid live (i.e. South Africa's west coast and Agulhas Bank) was prepared using published and new data. It included bottom temperature, bottom dissolved oxygen, chlorophyll, and copepod abundance. Alongshore gradients of these indicated that the main spawning grounds on the eastern Agulhas Bank are positioned where bottom temperature and bottom dissolved oxygen are optimal for embryonic development. This location, however, appears suboptimal for hatchlings because the copepod maximum (food for paralarvae) is typically on the central Agulhas Bank some 200 km to the west. Data on currents suggest that this constraint may be overcome by the existence of a net west-flowing shelf current on the eastern Agulhas Bank, improving survivorship of paralarvae by transporting them passively towards the copepod maximum. CTD data and a temporal analysis of AVHRR satellite imagery reveal the copepod maximum to be supported by a “cold ridge”, a mesoscale upwelling filament present during summer when squid spawning peaks. In situ sea surface temperature (SST) data used as a proxy for cold ridge activity demonstrate considerable interannual variability of the feature, especially during El Niño-Southern Oscillation events. Negative linear correlations between maximum summer SST (monthly average) and squid biomass the following autumn (r2 = 0.94), and annual catch (r2 = 0.69), support the link between the “cold ridge–copepod maximum” and the early life cycle of chokka squid, and holds promise for prediction.
Effect of changes in reproductive potential on perceived productivity of three Northwest Atlantic cod (Gadus morhua) stocks
Authors: Morgan M. Joanne , Brattey John
Published: December 2004

Variation in maturity-at-age, sex ratio, and potential egg production (through changes in length at age) were examined for northern cod (NAFO Division 2J + 3KL), southern Grand Bank cod (3NO), and southern Newfoundland cod (3Ps). All showed significant interannual variability in each stock. Estimates of reproductive potential were produced by sequentially incorporating estimates of proportion mature at age, sex ratio at age, and potential egg production. The estimates of reproductive potential produced by each method were broadly similar, but there were important differences. This leads to differing perceptions of stock productivity, as measured by relative rate of recruitment of a stock and in the spawning stock produced per recruit. These differing perceptions can have a major impact on expectations for the recovery of depleted stocks and the sustainability of various levels of fishing. Efforts should be made to improve estimates of reproductive potential by further exploring the impacts of changes in the spawning characteristics of populations, and by collecting such basic information as fecundity data.