bluuebunny/crossref_metadata_2025_split huggingface dataset:
Selection of Apoptosis-Deficient Adenovirus E4orf4 Mutants in
Saccharomyces cerevisiae
Authors: Afifi Rana , Sharf Rakefet , Shtrichman Ronit , Kleinberger Tamar 
Published: July 2002

ABSTRACT

Adenovirus E4orf4 protein has been shown to induce p53-independent, protein phosphatase 2A (PP2A)-dependent apoptosis in transformed cells. Furthermore, E4orf4 also induces toxicity in
Saccharomyces cerevisiae
in a PP2A-dependent manner (D. Kornitzer and T. Kleinberger, submitted for publication). In this work, we utilized yeast cells to select for nonapoptotic E4orf4 mutants which, in turn, were shown to possess a diminished ability to bind PP2A. The success of this selection system will provide additional apoptosis-relevant mutants for E4orf4 research and strongly supports the relevance of E4orf4-induced toxicity in
S. cerevisiae
to E4orf4-induced apoptosis in mammalian cells.
The Interacting UL31 and UL34 Gene Products of Pseudorabies Virus Are Involved in Egress from the Host-Cell Nucleus and Represent Components of Primary Enveloped but Not Mature Virions
Authors: Fuchs Walter , Klupp Barbara G. , Granzow Harald , Osterrieder Nikolaus , Mettenleiter Thomas C. 
Published: July 2002

ABSTRACT

A 2.6-kbp fragment of the pseudorabies virus (PrV) genome was sequenced and shown to contain the homologues of the highly conserved herpesvirus genes UL31 and UL32. By use of a monospecific antiserum, the UL31 gene product was identified as a nuclear protein with an apparent molecular mass of 29 kDa. For functional analysis, UL31 was deleted by mutagenesis in
Escherichia coli
of an infectious full-length clone of the PrV genome. The resulting virus mutants were deficient in plaque formation, and titers were reduced more than 100-fold from those of wild-type PrV. Ultrastructural analyses demonstrated that capsid maturation and DNA packaging were not affected. However, neither budding at the inner nuclear membrane nor cytoplasmic or extracellular virus particles were observed. These replication defects were similar to those of a UL34 deletion mutant (B. G. Klupp, H. Granzow, and T. C. Mettenleiter, J. Virol. 74:10063–10073, 2000) and could be completely repaired in a cell line which constitutively expresses the UL31 protein. Yeast two-hybrid studies revealed that a UL31 fusion protein specifically interacts with plasmids of a PrV genome library expressing the N-terminal part of UL34. Vice versa, UL34 selected UL31-encoding plasmids from the library. Immunofluorescence studies and immune electron microscopy demonstrated that in cells infected with wild-type PrV, both proteins accumulate at the nuclear membrane, whereas in the absence of UL34 the UL31 protein is dispersed throughout the nucleus. Like the UL34 protein, the UL31 gene product is a component of enveloped virus particles within the perinuclear space and absent from mature virions. Our findings suggest that physical interaction between these two virus proteins might be a prerequisite for primary envelopment of PrV at the inner nuclear membrane and that this envelope is removed by fusion with the outer nuclear membrane.
Potent Inhibition of Human Immunodeficiency Virus Type 1 Replication by Template Analog Reverse Transcriptase Inhibitors Derived by SELEX (Systematic Evolution of Ligands by Exponential Enrichment)
Authors: Joshi Pheroze , Prasad Vinayaka R. 
Published: July 2002

ABSTRACT

RNA aptamers derived by SELEX (systematic evolution of ligands by exponential enrichment) and specific for human immunodeficiency virus type 1 (HIV-1) reverse transcriptase (RT) bind at the template-primer cleft with high affinity and inhibit its activity. In order to determine the potential of such template analog RT inhibitors (TRTIs) to inhibit HIV-1 replication, 10 aptamers were expressed with flanking, self-cleaving ribozymes to generate aptamer RNA transcripts with minimal flanking sequences. From these, six aptamers (70.8,13, 70.15, 80.55,65, 70.28, 70.28t34, and 1.1) were selected based on binding constants (K

d

) and the degree of inhibition of RT in vitro (50% inhibitory concentration [IC
50
]). These six aptamers were each stably expressed in 293T cells followed by transfection of a molecular clone of HIV
R3B
. Analysis of the virion particles revealed that the aptamers were encapsidated into the virions released and that the packaging of the viral genomic RNA or the cognate primer, tRNA3Lys, was apparently unaffected. Infectivity of virions produced from 293T cell lines expressing the aptamers, as measured by infecting LuSIV reporter cells, was reduced by 90 to 99.5% compared to virions released from cells not expressing any aptamers. PCR analysis of newly made viral DNA upon infection with virions containing any of the three aptamers with the strongest binding affinities (70.8,13, 70.15, and 80.55,65) showed that all three were able to form the minus-strand strong-stop DNA. However, virions with the aptamers 70.8 and 70.15 were defective for first-strand transfer, suggesting an early block in viral reverse transcription. Jurkat T cells expressing each of the three aptamers, when infected with HIV
R3B
, completely blocked the spread of HIV in culture. We found that the replication of nucleoside analog RT inhibitor-, nonnucleoside analog RT inhibitor-, and protease inhibitor-resistant viruses was strongly suppressed by the three aptamers. In addition, some of the HIV subtypes were severely inhibited (subtypes A, B, D, E, and F), while others were either moderately inhibited (subtypes C and O) or were naturally resistant to inhibition (chimeric A/D subtype). As virion-encapsidated TRTIs can predispose virions for inhibition immediately upon entry, they should prove to be efficacious agents in gene therapy approaches for AIDS.
CD4 Independence of Simian Immunodeficiency Virus Envs Is Associated with Macrophage Tropism, Neutralization Sensitivity, and Attenuated Pathogenicity
Authors: Puffer Bridget A. , Pöhlmann Stefan , Edinger Aimee L. , Carlin Dan , Sanchez Melissa D. , Reitter Julie , Watry Debbie D. , Fox Howard S. , Desrosiers Ronald C. , Doms Robert W. 
Published: July 2002

ABSTRACT
To investigate the basis for envelope (Env) determinants influencing simian immunodeficiency virus (SIV) tropism, we studied a number of Envs that are closely related to that of SIVmac239, a pathogenic, T-tropic virus that is neutralization resistant. The Envs from macrophage-tropic (M-tropic) virus strains SIVmac316, 1A11, 17E-Fr, and 1100 facilitated infection of CCR5-positive, CD4-negative cells. In contrast, the SIVmac239 Env was strictly dependent upon the presence of CD4 for membrane fusion. We also found that the Envs from M-tropic virus strains, which are less pathogenic in vivo, were very sensitive to antibody-mediated neutralization. Antibodies to the V3-loop, as well as antibodies that block SIV gp120 binding to CCR5, efficiently neutralized CD4-independent, M-tropic Envs but not the 239 Env. However, triggering the 239 Env with soluble CD4, presumably resulting in exposure of the CCR5 binding site, made it as neutralization sensitive as the M-tropic Envs. In addition, mutations of N-linked glycosylation sites in the V1/V2 region, previously shown to enhance antigenicity and immunogenicity, made the 239 Env partially CD4 independent. These findings indicate that Env-based determinants of M tropism of these strains are generally associated with decreased dependence on CD4 for entry into cells. Furthermore, CD4 independence and M tropism are also associated with neutralization sensitivity and reduced pathogenicity, suggesting that the humoral immune response may exert strong selective pressure against CD4-independent M-tropic SIVmac strains. Finally, genetic modification of viral Envs to enhance CD4 independence may also result in improved humoral immune responses.
Promotion of Alpha/Beta Interferon Induction during In Vivo Viral Infection through Alpha/Beta Interferon Receptor/STAT1 System-Dependent and -Independent Pathways
Authors: Malmgaard Lene , Salazar-Mather Thais P. , Lewis Casey A. , Biron Christine A. 
Published: July 2002

ABSTRACTViruses and viral components can be potent inducers of alpha/beta interferons (IFN-α/β). In culture, IFN-α/β prime for their own expression, in response to viruses, through interferon regulatory factor 7 (IRF-7) induction. The studies presented here evaluated the requirements for functional IFN receptors and the IFN signaling molecule STAT1 in IFN-α/β induction during infections of mice with lymphocytic choriomeningitis virus (LCMV). At 24 h after infection, levels of induced IFN-α/β in serum were reduced 90 to 95% in IFN-α/β receptor-deficient (IFN-α/βR−/−) and STAT1−/−mice compared to those in wild-type mice. However, at 48 h, these mice showed elevated expression in the serum whereas IFN-α/β levels were still reduced >75% in IFN-α/βγR−/−mice even though the viral burden was heavy. Levels of IFN-β, IFN-α4, and non-IFN-α4 subtype mRNA expression correlated with IFN-α/β bioactivity, and all IFN-α/β subtypes were coincidentally detectable. IRF-7 mRNA was induced under conditions of IFN-α/β production, including late production in IFN-α/βR−/−mice. These data demonstrate that the presence of the virus alone is not sufficient to induce IFN-α/β during LCMV infection in vivo. Instead, autocrine amplification through the IFN-α/βR is necessary for optimal induction. In the absence of a functional IFN-α/βR, however, alternative mechanisms, independent of STAT1 but requiring a functional IFN-γR, take over.
Gas-Agitated Liquid-Liquid Extraction in a Spray Column
Authors: Sovilj Milan , Kneževic Goran 
Published: July 2002

The hydrodynamic characteristics of the air water toluene three-phase system in a spray extraction column at 20 °C were examined. The average and local hold-up data of the dispersed phase were determined in dependence on the flow rates of the continuous, dispersed and gaseous phases. The average gas phase hold-up was also measured and analyzed. A comparison was made of the hydrodynamic characteristics of the two-phase (water - toluene) and three-phase (air - water - toluene) systems.
Total serum IgE and outcome in infants with recurrent wheezing
Authors: Rusconi F , Patria M F , Cislaghi G U , Sideri S , Gagliardi L 
Published: July 2002

OBJECTIVETo investigate the relation between total serum IgE at 0.5–3 and 3–6 years, and the risk of allergic sensitisation and persistent wheezing up to 8 years of age.METHODSProspective follow up study of 45 infants with highly recurrent wheezing, no allergic symptoms, and negative skin tests.RESULTSIn the last follow up year, 15 children still suffered from wheezing. Five wheeze-free and four episodically wheezing children had become sensitised. No association was found between early (0.5–3 years) IgE z scores and the recurrence of wheezing during follow up, or atopic sensitisation. IgE z scores at 3–6 years were significantly higher in children with positive skin tests (p = 0.013), but were still not associated with recurrence of wheezing.CONCLUSIONSIn subjects with frequent early wheezing and no signs of atopy, early total serum IgE measurements are not predictive of outcome.
Increased urinary leukotriene E4during febrile attacks in the hyperimmunoglobulinaemia D and periodic fever syndrome
Authors: Frenkel J , Willemsen M A A P , Weemaes C M R , Dorland L , Mayatepek E 
Published: July 2002

BACKGROUNDThe hyperimmunoglobulinaemia D and periodic fever syndrome is a hereditary periodic fever, caused by deficiency of the enzyme mevalonate kinase. It is unclear how this defect leads to recurrent fever episodes.AIMTo assess the involvement of cysteinyl leukotrienes in the pathogenesis of fever attacks as reflected by urinary leukotriene E4(LTE4) excretion.METHODSUrinary LTE4was measured in seven patients while febrile and afebrile.RESULTSLTE4was raised during fever in all subjects (46–199 nmol/mol creatinine, mean 92; normal <40). Urinary LTE4was normal between attacks, as well as in normal children with fever as a result of miscellaneous causes.CONCLUSIONOur results suggest that cysteinyl leukotrienes play a role in the pathophysiology of this disorder. As no effective treatment is yet available, leukotriene receptor antagonists might offer a new therapeutic approach for patients with the hyperimmunoglobulinaemia D and periodic fever syndrome.
Long term health impact of playing professional football in the United Kingdom
Authors: Turner Andy P , Barlow Julie H , Heathcote-Elliott Christian 
Published: July 2002

Objective—To describe the long term impact of football on the health related quality of life (HRQL) of former professional footballers in the United Kingdom.Method—A cross sectional survey gathered data from 284 former professional players. Respondents reported medical treatments, osteoarthritis (OA) diagnosis, other morbidity, disability status, and work related disability since their football career. The EuroQol (EQ-5D) and global health rating scales were selected to assess HRQL.Results—Medical treatment for football related injuries was a common feature, as was OA, with the knee being the most commonly affected joint. Respondents with OA reported poorer HRQL compared with those without OA. As with medical treatments and problems on each of the five EQ-5D dimensions (pain, mobility, usual activities, anxiety/depression, self care), frequency of disability and work related disability were higher among respondents with OA than those without.Conclusion—This exploratory study suggests that playing professional football can impact on the health of United Kingdom footballers in later life. The development of OA was associated with poorer outcomes on all aspects of HRQL.
A unique insight into the incidence of rugby injuries using referee replacement reports
Authors: Sharp J C M , Murray G D , Macleod D A D 
Published: July 2002

Objectives—To obtain further information on the incidence of injuries and playing positions affected in club rugby in Scotland.Methods—Routine reports of injury (permanent) and blood (temporary) replacements occurring in competitive club rugby matches by referees to the Scottish Rugby Union during seasons 1990–1991 to 1996–1997 were analysed.Results—A total of 3513 injuries (87 per 100 scheduled matches) and 1000 blood replacements (34 per 100 scheduled matches) were reported. Forwards accounted for 60% of the injury and 72% of the blood replacements. Flankers and the front row were the most commonly replaced forwards while wing and centre three quarters were the most vulnerable playing positions among backs. The incidence of injury replacements increased as the match progressed up until the last 10 minutes when the trend was reversed. Blood replacements showed a different pattern with 60% occurring during the first half of the match.Conclusion—The most important finding of the study was reliability of referees in documenting the vulnerability of certain playing positions, and the timing when injuries took place, thus assisting coaches and team selectors when choosing replacement players for competitive club and representative rugby matches. This study re-emphasises the need for continuing epidemiological research.
Organisation of safety measures in an Alpine World Junior Championship
Authors: Bergstrøm K A , Bergstrøm A , Ekeland A 
Published: July 2002

Objectives—To study the implementation of skiing safety during the Alpine World Junior Championship of 1995.Methods—A map of the area was made with descriptions of the slopes and all its facilities and the security measures along the course. The number of competitors who started and any injuries reported were recorded in a questionnaire.Results—A total of 452 girls and 546 boys started in the different races. Only four injuries were recorded, all in girls. The overall injury rate was 4 per 1000 runs. An injury rate of 8.3 per 1000 runs was recorded in the downhill. One skier had a possibly severe injury (ISS = 14) in the downhill; the rest of the injuries were minor (ISS = 1). The mean ISS was 4.3 and the total ISS was 17.Conclusions—A significantly higher injury rate was recorded for young female than young male racers. The injury rate was significantly higher in downhill than the other alpine disciplines in the Alpine World Junior Championship. The injury rate was not significantly different from that recorded one year previously for Olympic racers, and juniors therefore need the same safety measures as Olympic racers.
Results of a 10 week community based strength and balance training programme to reduce fall risk factors: a randomised controlled trial in 65–75 year old women with osteoporosis
Authors: Carter N D , Khan K M , Petit M A , Heinonen A , Waterman C , Donaldson M G , Janssen P A , Mallinson A , Riddell L , Kruse K , Prior J C , Flicker L , McKay H A 
Published: July 2002

Objective—To test the efficacy of a community based 10 week exercise intervention to reduce fall risk factors in women with osteoporosis.Methods—Static balance was measured by computerised dynamic posturography (Equitest), dynamic balance by timed figure of eight run, and knee extension strength by dynamometry. Subjects were randomised to exercise intervention (twice weekly Osteofit classes for 10 weeks) or control groups.Results—The outcome in 79 participants (39 exercise, 40 control) who were available for measurement 10 weeks after baseline measurement is reported. After confounding factors had been controlled for, the exercise group did not make significant gains compared with their control counterparts, although there were consistent trends toward greater improvement in all three primary outcome measures. Relative to the change in control subjects, the exercise group improved by 2.3% in static balance, 1.9% in dynamic balance, and 13.9% in knee extension strength.Conclusions—A 10 week community based physical activity intervention did not significantly reduce fall risk factors in women with osteoporosis. However, trends toward improvement in key independent risk factors for falling suggest that a study with greater power may show that these variables can be improved to a level that reaches statistical significance.
Expression of human α-defensin 5 (HD5) mRNA in nasal and bronchial epithelial cells
Authors: Frye M , Bargon J , Dauletbaev N , Weber A , Wagner T O F , Gropp R 
Published: July 2002

Background/Aims—Human defensins are antibiotic peptides expressed in myeloid and epithelial cells. Human α-defensin 5 (HD5) has been detected in Paneth cell granules in the crypts of Lieberkühn and has recently been identified in the female reproductive tract. The aim of this study was to investigate the presence of HD5 mRNA in nasal and bronchial epithelial cells.Methods/Results—Semiquantitative reverse transcription polymerase chain reaction (RT–PCR) analysis showed that HD5 mRNA was expressed infrequently and to varying degrees in bronchial and nasal epithelial cells. In situ hybridisation resulted in a positive signal in the epithelial layer of nasal polyps. HD5 mRNA was locally restricted to a specific area of epithelial cells and also occurred in submucosal glands.Conclusions—HD5 mRNA expression in nasal and bronchial epithelial cells is rare and seemed to be locally induced. The results indicate that HD5 might play a role in innate defence in nasal and bronchial epithelia.
Dietary calcium supplementation increases apoptosis in the distal murine colonic epithelium
Authors: Penman I D , Liang Q L , Bode J , Eastwood M A , Arends M J 
Published: July 2002

Background—Increased dietary calcium might reduce colorectal cancer risk, possibly by reduction of colonic epithelial hyperproliferation, but not all studies have demonstrated this. Little is known about the effects of calcium on colonic apoptosis.Aim—To quantify the effects of increasing calcium on apoptosis and cell proliferation in normal murine colonic crypt epithelium.Methods—Twenty one day old male C57Bl/6 mice were fed either control AIN-76 diet (0.5% calcium wt/wt; n = 10) or the same supplemented with calcium carbonate (1.0% calcium; n = 10) for 12 weeks. Apoptotic cells in proximal and distal segments were counted and expressed as an apoptotic index (AI: frequency of apoptosis/100 longitudinal crypts). The bromodeoxyuridine (BrdU) labelling index was also determined. Differences were analysed by the student'sttest.Results—In control animals, the AI was significantly higher in the caecum/proximal colon (mean, 28.6; SEM, 2.0) compared with the distal colon (mean, 19.9; SEM, 1.8; p = 0.004). In the calcium treated group, the AI in the caecum/proximal colon (mean, 30.6; SEM, 1.7) was similar to controls (p = 0.71) but the AI in the distal colon was significantly greater (mean, 32.6; SEM, 1.8; p = 0.001) than in control mice and was raised to values similar to those in the proximal colon. Calcium was also associated with reduced crypt cellularity and, in the proximal colon, a downward shift in the crypt position at which apoptosis occurred. There were no significant differences in the BrdU labelling index between groups or between proximal and distal colonic segments in each group.Conclusions—Increased dietary calcium is associated with the induction of apoptosis in normal mouse distal colonic epithelium without affecting cell proliferation. This might contribute to its putative chemopreventive role in colorectal carcinogenesis. Whether this effect is direct or indirect requires further study.
Is consent in medicine a concept only of modern times?
Authors: Dalla-Vorgia P , Lascaratos J , Skiadas P , Garanis-Papadatos T 
Published: July 2002

Although the issue of consent in medical practice has grown immensely in recent years, and it is generally believed that historical cases are unknown, our research amongst original ancient Greek and Byzantine historical sources reveals that it is a very old subject which ancient philosophers and physicians have addressed. Plato, in ancient Greece, connected consent with the quality of a free person and even before him, Hippocrates had advocated seeking the patient's cooperation in order to combat the disease. In Alexander the Great's era and later on in Byzantine times, not only was the consent of the patient necessary but physicians were asking for even more safeguards before undertaking a difficult operation.Our study has shown that from ancient times physicians have at least on occasion been driven to seek the consent of their patient either because of respect for the patient's autonomy or from fear of the consequences of their failure.