bluuebunny/crossref_metadata_2025_split huggingface dataset:
Kaposi's Sarcoma-Like Tumors in a Human Herpesvirus 8 ORF74 Transgenic Mouse
Authors: Guo Hong-Guang , Sadowska Mariola , Reid William , Tschachler Erwin , Hayward Gary , Reitz Marvin 
Published: January 2003

ABSTRACT

The product of human herpesvirus 8 (HHV-8) open reading frame 74 (ORF74) is related structurally and functionally to cellular chemokine receptors. ORF74 activates several cellular signaling pathways in the absence of added ligands, and NIH 3T3 cells expressing ORF74 are tumorigenic in nude mice. We have generated a line of transgenic (Tg) mice with ORF74 driven by the simian virus 40 early promoter. A minority (approximately 30%) of the Tg mice, including the founder, developed tumors resembling Kaposi's sarcoma (KS) lesions, which occurred most typically on the tail or legs. The tumors were highly vascularized, had a spindle cell component, expressed VEGF-C mRNA, and contained a majority of CD31
+
cells. CD31 and VEGF-C are typically expressed in KS. Tumors generally (but not always) occurred at single sites and most were relatively indolent, although several mice developed large visceral tumors. ORF74 was expressed in a minority of cells in the Tg tumors and in a few other tissues of mice with tumors; mice without tumors did not express detectable ORF74 in any tissues tested. Cell lines established from tumors expressed ORF74 in a majority of cells, expressed VEGF-C mRNA, and were tumorigenic in nude mice. The resultant tumors grew rapidly, metastasized, and continued to express ORF74. Cell lines established from these secondary tumors also expressed ORF74 and were tumorigenic. These data strongly suggest that ORF74 plays a role in the pathology of KS and confirm and extend previous findings on the tumorigenic potential of ORF74.
Interaction of the Equine Herpesvirus 1 EICP0 Protein with the Immediate-Early (IE) Protein, TFIIB, and TBP May Mediate the Antagonism between the IE and EICP0 Proteins
Authors: Kim Seong K. , Jang Hyung K. , Albrecht Randy A. , Derbigny Wilbert A. , Zhang Yunfei , O'Callaghan Dennis J. 
Published: January 2003

ABSTRACT

The equine herpesvirus 1 (EHV-1) immediate-early (IE) and EICP0 proteins are potent
trans
-activators of EHV-1 promoters; however, in transient-transfection assays, the IE protein inhibits the
trans-
activation function of the EICP0 protein. Assays with IE mutant proteins revealed that its DNA-binding domain, TFIIB-binding domain, and nuclear localization signal may be important for the antagonism between the IE and EICP0 proteins. In vitro interaction assays with the purified IE and EICP0 proteins indicated that these proteins interact directly. At late times postinfection, the IE and EICP0 proteins colocalized in the nuclei of infected equine cells. Transient-transfection assays showed that the EICP0 protein
trans
-activated EHV-1 promoters harboring only a minimal promoter region (TATA box and cap site), suggesting that the EICP0 protein
trans
-activates EHV-1 promoters by interactions with general transcription factor(s). In vitro interaction assays revealed that the EICP0 protein interacted directly with the basal transcription factors TFIIB and TBP and that the EICP0 protein (amino acids [aa] 143 to 278) mediated the interaction with aa 125 to 174 of TFIIB. Our unpublished data showed that the IE protein interacts with the same domain (aa 125 to 174) of TFIIB and with TBP. Taken together, these results suggested that interaction of the EICP0 protein with the IE protein, TFIIB, and TBP may mediate the antagonism between the IE and EICP0 proteins.
High Mutant Frequency in Populations of a DNA Virus Allows Evasion from Antibody Therapy in an Immunodeficient Host
Authors: López-Bueno Alberto , Mateu Mauricio G. , Almendral José M. 
Published: January 2003

ABSTRACT

The degree of genetic heterogeneity of DNA virus populations in nature and its consequences for disease control are virtually unknown. The parvovirus minute virus of mice (MVMi) was used here to investigate (i) the frequency of antibody-escape mutants in populations of a DNA virus and (ii) the ability of a DNA virus to evade in the long-term a passive monoclonal antibody (MAb) therapy in an immunodeficient natural host. Independent clonal populations of MVMi harbored a high proportion of mutants resistant to neutralizing MAb (mutant frequency = [2.8 ± 0.5] × 10
−5
) that rapidly evolved under antibody pressure in culture to become mixtures dominated by genotypically diverse escape mutants. Immunodeficient mice naturally infected with clonal populations of MVMi and subsequently treated by intravenous injections of MAb were initially protected from the characteristic viral induced lethal leukopenia. However, some treated animals developed a delayed severe leukopenic syndrome associated with the emergence of genetically heterogeneous populations of MAb-resistant mutants in the MVMi main target organs. The 11 plaque-purified viruses analyzed from an antibody-resistant population obtained from one animal corresponded to four different mutant genotypes, although their consensus sequence remained wild type. All cloned escape mutants harbored single radical amino acid changes within a stretch of seven residues in a surface-exposed loop at the threefold axes of the capsid. This antigenic site, which can tolerate radical changes preserving MVMi pathogenic potential, may thereby allow the virus to evade the immune control. These findings indicate a high genetic heterogeneity and rapid adaptation of populations of a mammal DNA virus in vivo and provide a genetic basis for the failure of passive immunotherapy in the natural host.
Novel Gene Product of
Thogoto Virus
Segment 6 Codes for an Interferon Antagonist
Authors: Hagmaier Kathrin , Jennings Stephanie , Buse Johanna , Weber Friedemann , Kochs Georg 
Published: January 2003

ABSTRACT

Thogoto virus
(THOV) is a tick-transmitted orthomyxovirus with a genome of six negative-stranded RNA segments. The sixth segment encodes two different transcripts: a spliced transcript that is translated into the matrix protein (M) and an unspliced transcript. Here, we report that the unspliced transcript encodes an elongated form of M named ML. A THOV isolate deficient in ML expression was an efficient interferon inducer, whereas ML-expressing wild-type strains were poor interferon inducers. These results were confirmed with recombinant THOVs rescued from cDNAs. Expression of ML efficiently suppressed activation of the beta interferon promoter by double-stranded RNA. These results indicate that ML is an accessory protein that functions as a potent interferon antagonist by blocking transcriptional activation of alpha/beta interferons.
Ambiguous relation between physical workload and low back pain: a twin control study
Authors: Hartvigsen J , Kyvik K O , Leboeuf-Yde C , Lings S , Bakketeig L 
Published: January 2003

Aims:To examine the association between self reported physical workload and low back pain (LBP) in younger twins. To investigate whether genetic factors interact with physical workload in relation to LBP.Methods:A twin control study was performed within a population based twin register using 1910 complete monozygotic (MZ) and same sexed dizygotic (DZ) twin pairs aged 25–42 and discordant for LBP. LBP in the affected twins was divided into two groups: “LBP for ≤30 days during the past year”, and “LBP for >30 days during the past year”. Physical workload was divided into four categories: “sitting”, “sitting/walking”, “light physical”, and “heavy physical”. Data were analysed in a matched design using conditional logistic regression. MZ and DZ twins were analysed separately and together in order to determine possible genetic influences in relation to physical workload and LBP.Results:Statistically significant graded relations were found for increasing workload and LBP of longer duration but not for LBP of shorter duration (≤30 days during the past year). In both LBP groups the “sitting” and “sitting/walking” groups were not statistically different. MZ and DZ twins did not differ significantly with respect to LBP in the various workload groups.Conclusions:There is evidence for a dose-response relation between physical workload and LBP of longer duration. Attention to clinically relevant subgroups based on duration, for example, is necessary in epidemiological studies dealing with LBP. Physical workload might be more important than genetic factors in LBP.
Follow up study of haematological effects in workers exposed to 2-methoxyethanol
Authors: Shih T-S , Hsieh A-T , Chen Y-H , Liao G-D , Chen C-Y , Chou J-S , Liou S-H 
Published: January 2003

Aims:To examine the association between 2-methoxyethanol (2-ME) exposure and haematological effects, as well as the recovery from these haematological effects with continuous reduction in exposure to 2-ME.Methods:Twenty nine exposed and 90 non-exposed workers were recruited. Haematological parameters, eight hour full shift personal exposure to 2-ME, and urinary 2-methoxyacetic acid (MAA) were repeatedly measured in three consecutive surveys within six months.Results:Results of haematological examination in the first exposure survey showed that haemoglobin, packed cell volume, and red blood cell count in the male exposed workers were significantly lower than those in the comparison workers. The frequency of anaemia in the exposed group (42%) was significantly higher than that in the comparison group (3%). The haematological effects were significantly associated with the urinary MAA of exposed workers. The haematological effects had returned to normal in the first follow up survey 2.5 months later, when a reduction in 2-ME exposure was noted. Haematological results of the second follow up examination six months later remained normal. The mean airborne exposure of 2-ME in the three surveys dropped from 35.7 to 2.65, then to 0.55 ppm. The mean urinary MAA of exposed workers in the three surveys was reduced from 57.7 to 24.6, then to 13.5 mg/g creatinine (n = 29). The reduction in exposure through both inhalation and potential dermal contact with 2-ME might account for the haematological recovery.Conclusion:2-ME is a haematological toxin which leads to anaemia in exposed workers. However, the toxic haematological effects of 2-ME persist for only a short period of time after cessation or reduction of exposure.
Acute effects of winter air pollution on respiratory function in schoolchildren in southern England
Authors: Peacock J L , Symonds P , Jackson P , Bremner S A , Scarlett J F , Strachan D P , Anderson H R 
Published: January 2003

Aim:To investigate the acute health effects of winter outdoor air pollution (nitrogen dioxide (NO2), ozone (O3), sulphur dioxide (SO2), sulphate (SO42−) ,and particles (PM10)) on schoolchildren in an area of southern England where levels of SO2had been reported to be high.Methods:A total of 179 children, aged 7–13, from three schools (two urban and one rural location), were included. Peak expiratory flow rate (PEFR) and presence or absence of upper respiratory infections were recorded on 63 school days from 1 November 1996 to 14 February 1997. Air pollution and meteorological data were taken from monitors at each school site. The analysis regressed daily PEFR on pollutant level adjusting for confounders and serial correlation and calculated a weighted pooled estimate of effect overall for each pollutant. In addition, large decrements in PEFR were analysed as a binary outcome. Same day, lag 1, lag 2, and a five day average of pollutant levels were used.Results:There were no clear effects of any pollutant on mean PEFR. In addition, we analysed large PEFR decrements (a binary outcome), observing consistent negative associations with NO2, SO42−, and PM10, although few lag/pollutant combinations were significant: odds ratios (95% CI) for five day average effect: NO224 h average 1.043 (1.000 to 1.089), SO42−1.090 (0.898 to 1.322), PM101.037 (0.992 to 1.084). The observed effects of PM10(only) were stronger in wheezy children (1.114 (1.057 to 1.174)). There were no consistent negative associations between large decrements and ozone or SO2.Conclusions:There is no strong evidence for acute effects of winter outdoor air pollution on mean PEFR overall in this area, but there is evidence for negative effects on large PEFR decrements.
ON THE SHAPE OF THE SOLUTIONS OF SOME SEMILINEAR ELLIPTIC PROBLEMS
Authors: GROSSI MASSIMO , MOLLE RICCARDO 
Published: January 2003

This paper deals with semilinear elliptic problems of Dirichlet type, in star shaped domains. An abstract result is stated, which gives sufficient conditions for a positive solution of the problem to have strictly star shaped superlevels. Moreover, it turns out that the maximum point is the only critical point for these solutions. Then we apply the result to the "single-peak" solutions of some widely studied problems. First a nonlinear and subcritical elliptic equation is considered, when the nonlinearity approaches the critical one. Then Schrödinger type problems are studied. Finally, the case when the potential is constant is also analyzed, on a bounded domain.
Estrogen Receptor (ER)-β Reduces ERα-Regulated Gene Transcription, Supporting a “Ying Yang” Relationship between ERα and ERβ in Mice
Authors: Lindberg Marie K. , Movérare Sofia , Skrtic Stanko , Gao Hui , Dahlman-Wright Karin , Gustafsson Jan-Åke , Ohlsson Claes 
Published: January 2003

Abstract
Estrogen is of importance for the regulation of adult bone metabolism. The aim of the present study was to determine the role of estrogen receptor-β (ERβ) in vivo on global estrogen-regulated transcriptional activity in bone. The effect of estrogen in bone of ovariectomized mice was determined using microarray analysis including 9400 genes. Most of the genes (95% = 240 genes) that were increased by estrogen in wild-type (WT) mice were also increased by estrogen in ERβ-inactivated mice. Interestingly, the average stimulatory effect of estrogen on the mRNA levels of these genes was 85% higher in ERβ-inactivated than in WT mice, demonstrating that ERβ reduces estrogen receptor-α (ERα)-regulated gene transcription in bone. The average stimulatory effect of estrogen on estrogen-regulated bone genes in ERα-inactivated mice was intermediate between that seen in WT and ERαβ double-inactivated mice. Thus, ERβ inhibits ERα-mediated gene transcription in the presence of ERα, whereas, in the absence of ERα, it can partially replace ERα. In conclusion, our in vivo data indicate that an important physiological role of ERβ is to modulate ERα-mediated gene transcription supporting a “Ying Yang” relationship between ERα and ERβ in mice.
Impact of flow through the Canadian Archipelago and Bering Strait on the North Atlantic and Arctic circulation: An ocean modelling study
Authors: Wadley Martin R. , Bigg Grant R. 
Published: January 2003

AbstractAn ocean general‐circulation model with an orthogonal curvilinear grid is presented, with the grid north pole over Greenland to achieve improved resolution in the Greenland and Labrador Seas. The model is integrated for 4500 years in five different experiments, with open and closed connections to the Arctic via the Bering Strait (BS) and Canadian Archipelago (CA). When the BS and CA connections are open the Atlantic overturning circulation has a realistic strength (20 Sv), whereas there is stronger overturning with either (25–31 Sv) or both (39 Sv) the connections closed due to additional deep‐water formation in the Labrador Sea. The volume fluxes across the Greenland–Iceland–Scotland ridge are reasonably close to those observed with the two connections either open or closed. With only the BS closed, low‐salinity waters leave the Arctic via the CA, giving a weak East Greenland Current, whereas with only the CA closed deep‐water formation in the Nordic Seas is weak due to the passage of excess low‐salinity water originating from the Pacific via the BS. The simulations suggest that both the CA and BS connections to the Arctic Influence the North Atlantic circulation. Closing the BS reduces the effective freshwater input to the Arctic, leading to a strong Atlantic overturning circulation. Closing the CA leads to increased salinity in the Labrador Sea, and additional deep‐water formation. It is therefore recommended that both these seaways should be represented in ocean general‐circulation models. Copyright © 2002 Royal Meteorological Society
Large‐scale organization of tropical convection in two‐dimensional explicit numerical simulations: Effects of interactive radiation
Authors: Grabowski Wojciech W. , Moncrieff Mitchell W. 
Published: January 2003

AbstractWe examine interactions among radiative processes, water vapour, clouds, and the multi‐scale organization of tropical convection in two‐dimensional idealized cloud‐resolving simulations using planetary‐scale horizontal domains. We extend our earlier study where radiative cooling was prescribed. Therein, deep convection spontaneously organized into two primary scales: westward travelling mesoscale convective systems on a scale of a few hundred kilometres and the eastward‐propagating envelopes of convection spanning thousands of kilometres. These envelopes represented large‐scale convectively coupled gravity waves, two‐dimensional non‐rotating analogues of equatorially trapped Kelvin waves.Interactive radiation introduces a new mechanism of large‐scale convective organization. Weak overturning circulations, steered by the mean wind and of a few thousand kilometres in scale, gradually develop. This overturning is a manifestation of the baroclinic response to horizontal gradients of radiative heating established between the moist and dry regions, which causes a spontaneous positive feedback among large‐scale dynamics, water vapour, clouds, and radiation. The mechanism is as follows: the convective systems maintain the humidity (vapour and cloud) in the ascending branch which, in turn, maintains the differential radiative heating. Conversely, the large‐scale overturning provides the large‐scale dynamical forcing that maintains the deep convection. This quantifies recent idealized studies that applied convective parametrizations. The radiatively driven overturning and the deep convection are modulated by large‐scale convectively coupled gravity waves responsible for the large‐scale envelopes reported earlier. A series of sensitivity tests, including the effects of environmental shear, demonstrate the robustness of these results. Copyright © 2002 Royal Meteorological Society
Measurements of the near‐surface flow over a hill
Authors: Vosper S. B. , Mobbs S. D. , Gardiner B. A. 
Published: January 2003

AbstractThe near‐surface flow over a hill with moderate slope and height comparable with the boundary‐layer depth is investigated through field measurements of the mean flow (at 2 m), surface pressure, and turbulent momentum flux divergence between 8 and 15 m. The measurements were made along an east–west transect across the hill Tighvein (height 458 m, approximate width 8 km) on the Isle of Arran, south‐west Scotland, during two separate periods, each of around three‐weeks duration. Radiosonde ascents are used to determine the variation of a Froude number, FL=U/NL, where U is the wind speed at the middle‐layer height, hm, N is the mean Brunt–Väisälä frequency below this height and L is a hill length‐scale. Measurements show that for moderately stratified flows (for which FL≳0.25) a minimum in the hill‐induced surface‐pressure perturbation occurs across the summit and this is accompanied by a maximum in the near‐surface wind speed. In the more strongly stratified case FL≲0.25 the pressure field is more asymmetric and the lee‐slope flow is generally stronger than on the windward slope. Such a flow pattern is qualitatively consistent with that predicted by stratified linear boundary‐layer and gravity‐wave theories. The near‐surface momentum budget is analysed by evaluating the dominant terms in a Bernoulli equation suitable for turbulent flow. Measurements during periods of westerly flow are used to evaluate the dominant terms, and the equation is shown to hold to a reasonable approximation on the upwind slope of the hill and also on the downwind slope, away from the summit. Immediately downwind of the summit, however, the Bernoulli equation does not hold. Possible reasons for this, such as non‐separated sheltering and flow separation, are discussed. Copyright © 2002 Royal Meteorological Society
Retrieval of temperature, water vapour and ozone profiles from airborne interferometric measurements
Authors: Grippa M. , Peckham G. E. 
Published: January 2003

AbstractThe Airborne Research Interferometer Evaluation System (ARIES), flying on board the Meteorological Research Flight C130 aircraft, measures infrared radiance spectra from which tropospheric temperature and composition profiles can be determined by solving an inverse ill‐posed problem. We have derived a new regularization scheme for the linearized problem based on the idea that, in a stable atmosphere, the temperature lapse rate never exceeds its adiabatic value, so that a constraint may be applied to the temperature retrievals. The retrieval method is validated by means of an extensive simulation and by analysis of the ARIES data. Water vapour is retrieved simultaneously with temperature, putting particular emphasis on the linearization of the forward model and on the evaluation of the linearization pseudo‐noise associate with it. Preliminary results indicating the potential of ARIES measurements to retrieve tropospheric ozone profiles are also presented. Copyright © 2002 Royal Meteorological Society
Tropical convective variability in the CAPE phase space
Authors: Roff Gregory L. , Yano Jun‐Ichi 
Published: January 2003

AbstractThe relationship between pseudo‐adiabatic and reversible convective available potential energy (CAPE) in the tropical atmosphere is examined using the Tropical Ocean–Global Atmosphere programme (TOGA) Coupled Ocean–Atmosphere Response Experiment (COARE) radiosonde dataset. The effect of the ice phase and the dependence of the various CAPE quantities on surface variabilities is also examined.CAPE distribution is qualitatively different for the regimes with positive and negative reversible CAPE (rCAPE). The former is characterized by a strong linear relationship (synchronic line) with a slightly weaker increase of rCAPE than that of pseudo‐adiabatic CAPE, with its evolution primarily dictated by the surface moisture. This synchronic line also penetrates into the negative rCAPE regime, where CAPE distributes diffusively between this synchronic line and a line with zero reversible CAPE. These more complex distributions of CAPE in the negative rCAPE regime are explained by their dependence on the level of neutral buoyancy. Copyright © 2002 Royal Meteorological Society
Ice nucleation characteristics of an isolated wave cloud
Authors: Cotton R. J. , Field P. R. 
Published: January 2003

AbstractThis paper reports on a series of simulations of a single isolated gravity‐wave cloud measured during the Interaction of Aerosol and Cold Clouds campaign. Using a parcel model with explicit liquid‐ and ice‐phase microphysics, a number of different heterogeneous nucleation modes have been tested. It has been impossible for the model to reproduce, using any of the usual nucleation modes, both the observed peak ice number concentration and the ice water content, while not affecting the liquid‐water part of the cloud. The key to simulating both of these simultaneously appears to lie in most ice nucleation occurring very rapidly at a critical time coincident with evaporation of the liquid droplets in the downdraught of the lee wave. © Crown copyright, 2002. Royal Meteorological Society