bluuebunny/crossref_metadata_2025_split huggingface dataset:
Mechanism of Cell Entry and Transformation by Enzootic Nasal Tumor Virus
Authors: Dirks Clarissa , Duh Fuh-Mei , Rai Sharath K. , Lerman Michael I. , Miller A. Dusty 
Published: July 2002

ABSTRACT
Enzootic nasal tumor virus (ENTV) induces nasal epithelial cancer in infected sheep, but it is a simple retrovirus lacking a known oncogene. ENTV is closely related to jaagsiekte sheep retrovirus (JSRV), which also causes cancer in sheep but in the epithelial cells of the lower airways and alveoli. Here we show that as with JSRV, the envelope (Env) protein of ENTV can transform cultured cells and thus is likely to be responsible for oncogenesis in animals. In addition, the ENTV Env protein mediates virus entry using the same receptor as does JSRV Env, the candidate tumor suppressor Hyal2. However, ENTV Env mediates entry into cells from a more restricted range of species than does JSRV, and based on this finding we have identified amino acid regions in the Env proteins that are important for virus entry. Also, because ENTV does not efficiently use human Hyal2 as a receptor, we cloned the ovine Hyal2 cDNA and show that the encoded protein functions as an efficient receptor for both ENTV and JSRV. In summary, although ENTV and JSRV use the same cell surface receptor for cell entry and apparently transform cells by the same mechanism, they induce cancer in different tissues of infected sheep, indicating that oncogenesis is regulated at some other level. The transcriptional regulatory elements in these viruses are quite different, indicating that tissue-specific oncogenesis is likely regulated at the level of viral gene expression.
Myxoma Virus Leukemia-Associated Protein Is Responsible for Major Histocompatibility Complex Class I and Fas-CD95 Down-Regulation and Defines Scrapins, a New Group of Surface Cellular Receptor Abductor Proteins
Authors: Guerin Jean-Luc , Gelfi Jacqueline , Boullier Severine , Delverdier Maxence , Bellanger Frederique-Anne , Bertagnoli Stephane , Drexler Ingo , Sutter Gerd , Messud-Petit Frederique 
Published: July 2002

ABSTRACTDown-modulation of major histocompatibility class I (MHC-I) molecules is a viral strategy for survival in the host.Myxoma virus, a member of thePoxviridaefamily responsible for rabbit myxomatosis, can down-modulate the expression of MHC-I molecules, but the viral factor(s) has not been described. We cloned and characterized a gene coding for an endoplasmic reticulum (ER)-resident protein containing an atypical zinc finger and two transmembrane domains, which we called myxoma virus leukemia-associated protein (MV-LAP). MV-LAP down-regulated surface MHC-I and Fas-CD95 molecules upon transfection; the mechanism probably involves an exacerbation of endocytosis and was lost when the ER retention signal was removed. In addition, the lytic activity of MHC-I-restricted antigen-specific cytolytic T lymphocytes (CTL) against myxoma virus-infected antigen-presenting target cells was significantly reduced, revealing a strong correlation between MHC-I down-regulation by MV-LAP and CTL killing in vitro. In vivo experiments with a knockout virus showed that MV-LAP is a virulence factor, potentially involved in the immunosuppression characteristic of myxomatosis. Data bank analysis revealed that MV-LAP has homologs in herpesviruses and other poxviruses. We propose the name “scrapins” to define a new group of ER-resident surface cellular receptor abductor proteins. The down-regulation of cell surface molecules by scrapins probably helps protect infected cells during viral infections.
Efficient Concerted Integration by Recombinant Human Immunodeficiency Virus Type 1 Integrase without Cellular or Viral Cofactors
Authors: Sinha Sapna , Pursley Michael H. , Grandgenett Duane P. 
Published: July 2002

ABSTRACT
Replication of retroviruses requires integration of the linear viral DNA genome into the host chromosomes. Integration requires the viral integrase (IN), located in high-molecular-weight nucleoprotein complexes termed preintegration complexes (PIC). The PIC inserts the two viral DNA termini in a concerted manner into chromosomes in vivo as well as exogenous target DNA in vitro. We reconstituted nucleoprotein complexes capable of efficient concerted (full-site) integration using recombinant wild-type human immunodeficiency virus type I (HIV-1) IN with linear retrovirus-like donor DNA (480 bp). In addition, no cellular or viral protein cofactors are necessary for purified bacterial recombinant HIV-1 IN to mediate efficient full-site integration of two donor termini into supercoiled target DNA. At ∼30 nM IN (20 min at 37°C), approximately 15 and 8% of the input donor is incorporated into target DNA, producing half-site (insertion of one viral DNA end per target) and full-site integration products, respectively. Sequencing the donor-target junctions of full-site recombinants confirms that 5-bp host site duplications have occurred with a fidelity of ∼70%, similar to the fidelity when using IN derived from nonionic detergent lysates of HIV-1 virions. A key factor allowing recombinant wild-type HIV-1 IN to mediate full-site integration appears to be the avoidance of high IN concentrations in its purification (∼125 μg/ml) and in the integration assay (<50 nM). The results show that recombinant HIV-1 IN may not be significantly defective for full-site integration. The findings further suggest that a high concentration or possibly aggregation of IN is detrimental to the assembly of correct nucleoprotein complexes for full-site integration.
Varicella-Zoster Virus Open Reading Frame 2 Encodes a Membrane Phosphoprotein That Is Dispensable for Viral Replication and for Establishment of Latency
Authors: Sato Hitoshi , Pesnicak Lesley , Cohen Jeffrey I. 
Published: July 2002

ABSTRACT
Varicella-zoster virus (VZV) encodes six genes that do not have homologs in herpes simplex virus. One of these genes, VZV open reading frame 2 (ORF2), was expressed as a 31-kDa phosphoprotein in the membranes of infected cells. Unlike equine and bovine herpesvirus type 1 ORF2 homologs that are associated with virions, VZV virions contained no detectable ORF2 protein. The ORF2 deletion mutant established a latent infection in cotton rats at a frequency and with a number of VZV genomes similar to that of the parental virus. ORF63 transcripts, a hallmark of latent infection, were present in ganglia latently infected with both the ORF2 deletion mutant and parental VZV. Thus, ORF2 is the first VZV gene shown to be dispensable for establishment of latent infection in an animal model.
Effect of the V3 Loop Deletion of Envelope Glycoprotein on Cellular Responses and Protection against Challenge with Recombinant Vaccinia Virus Expressing gp160 of Primary Human Immunodeficiency Virus Type 1 Isolates
Authors: Kiszka Irena , Kmieciak Dariusz , Gzyl Jaroslaw , Naito Toshio , Bolesta Elizabeth , Sieron Aleksander , Singh Satya P. , Srinivasan Alagarsamy , Trinchieri Giorgio , Kaneko Yutaro , Kozbor Danuta 
Published: July 2002

ABSTRACTThe magnitude and breadth of cytotoxic-T-lymphocyte (CTL) responses induced by human immunodeficiency virus type 1 (HIV-1) envelope protein from which the hypervariable V3 loop had been deleted (ΔV3) were evaluated in the HLA-A2/Kbtransgenic mice. It was demonstrated that vaccines expressing the ΔV3 mutant of either HIV-1IIIBor HIV-189.6envelope glycoprotein induced broader CD8+T-cell activities than those elicited by the wild-type (WT) counterparts. Specifically, the differences were associated with higher responses to conserved HLA-A2-restricted CTL epitopes of the envelope glycoprotein and could be correlated with an increased cell surface occupancy by the epitope-HLA-A2 complexes in target cells expressing the ΔV3 mutant. Using recombinant vaccinia virus expressing heterologous gp160 of primary HIV-1 isolates in a murine challenge system, we observed that the extent of resistance to viral transmission was higher in animals immunized with the ΔV3 than the WT envelope vaccine. The protection was linked to the presence of envelope-specific CD8+T cells, since depletion of these cells by anti-CD8 antibody treatment at the time of challenge abolished the vaccine-induced protection. The results from our studies provide insights into approaches for boosting the breadth of envelope-specific CTL responses.
Investigation of Catechin and Acridine Derivatives Using Voltammetric and Fluorimetric DNA-Based Sensors
Authors: Vaníčková Mária , Labuda Ján , Bučková Miriam , Surugiu Ioana , Mecklenburg Michael , Danielsson Bengt 
Published: July 2002

The preconcentration-differential pulse voltammetric detection scheme with a carbon paste electrode bulk phase modified with DNA was used for the investigation of behaviour and the determination of trace levels of catechin and acridine derivatives. The effect of electrochemical activation of the electrode and the DNA-type was examined. The results are compared with those obtained by fluorimetric measurement of the TO-PRO-3 dye : DNA complex in the presence of analytes. With voltammetric biosensors, the detection limits are in the nmol l-1 concentration region. Using competitive reagents, the intercalation of analytes to DNA is indicated.
Cyclization of Substituted Phenyl N-(2-Hydroxybenzyl)carbamates in Aprotic Solvents. Synthesis of 4H-1,3-Benzoxazin-2(3H)-ones
Authors: Mindl Jaromír , Hrabík Oldřich , Štěrba Vojeslav , Kaválek Jaromír 
Published: July 2002

The kinetics of cyclization of substituted phenyl N-(2-hydroxybenzyl)carbamates and their N-methyl analogs, prepared by the reaction of 2-(aminomethyl)phenols with substituted phenyl chloroformates, was studied in dioxane or toluene at the temperatures 110-180 °C. Electron-withdrawing substituents in the leaving phenoxy group strongly accelerate the rate of cyclization (ρ = 2.45 ± 0.15) while the substituents in the other ring have virtually no effect. The cyclization was catalyzed with triethylamine in toluene but not in dioxane. On the basis of these results, the most convenient method for preparation of substituted 4H-1,3-benzoxazin-2(3H)-ones was a one-hour reflux of substituted 4-nitrophenyl N-(2-hydroxybenzyl)carbamates in dioxane. Based on the influence of substituents, solvents (dioxane and toluene) and triethylamine, the reaction mechanism and structure of the transition state were proposed.
A pilot study examining injuries in elite gaelic footballers
Authors: Cromwell F , Walsh J , Gormley J 
Published: July 2002

Objectives—To quantify injuries in elite gaelic footballers and to determine the nature, sites, and outcome of injuries and the possible risk factors involved.Methods—Information on injuries was collected from six elite gaelic football teams by a questionnaire. The footballers were asked to recall injuries over the preceding six month period.Results—A total of 88 out of 107 subjects sustained injuries over the study period. Ninety five injuries were recorded, giving an incidence rate of 1.78 injuries per subject per year, of which 35% were recurring. It was found that 35% of injuries were sustained during training sessions. Lower body injuries predominated (77%), the ankle being the most commonly injured anatomic site. Most injuries were soft tissue in nature: muscle, 33%; ligament, 32%; tendon, 16%. The most common situations giving rise to injuries were collision (22%) and twist/turn (19%). Foul play only accounted for about 6% of injuries. Mean time off play as a result of injury was 17.3 days, and hospital admission was necessary for 15% of the injuries.Conclusion—Despite the limitations of a retrospective of this nature, the study provides useful and important information on injuries in gaelic footballers.
Stress reactivity to and recovery from a standardised exercise bout: a study of 31 runners practising relaxation techniques
Authors: Solberg E E , Ingjer F , Holen A , Sundgot-Borgen J , Nilsson S , Holme I 
Published: July 2002

Objective—To compare the efficacy in runners of two relaxation techniques with regard to exercise reactivity and recovery after exercise.Methods—Thirty one adult male runners were studied prospectively for six months in three groups practising either meditation (n = 11) or autogenic training (n = 11) or serving as controls (n = 10). Before and after the six months relaxation intervention, indicators of reactivity to exercise and metabolism after exercise (blood lactate concentration, heart rate (HR), and oxygen consumption (Vo2)), were tested immediately after and 10 minutes after exercise. Resting HR was also assessed weekly at home during the trial. State anxiety was measured before and after the intervention.Results—After the relaxation training, blood lactate concentration after exercise was significantly (p<0.01) decreased in the meditation group compared with the control group. No difference was observed in lactate responses between the autogenic training group and the control group. There were no significant differences among the groups with regard to HR, Vo2, or levels of anxiety.Conclusion—Meditation training may reduce the lactate response to a standardised exercise bout.
Sepsis and mechanisms of inflammatory response: is exercise a good model?
Authors: Shephard R J 
Published: July 2002

Objectives—The immune changes induced by a bout of prolonged and vigorous exercise have been suggested to be a useful experimental model of sepsis and the inflammatory response. Available literature was reviewed to evaluate this hypothesis.Methods—Literature describing the immune response to various patterns of exercise was compared with data on the immune changes observed during sepsis and inflammation.Results—Although there are qualitative similarities between the immune responses to exercise and sepsis, the magnitude of the changes induced by most forms of exercise remains much smaller than in a typical inflammatory response. Indeed, the exercise induced changes in some key elements such as plasma cytokine concentrations are too small to be detected reliably by current technology.Conclusions—If exercise is to provide a valid model of sepsis and the inflammatory response, it will be necessary to focus on subjects who are willing to exercise extremely hard, to use the pattern of exercise that has the greatest effect on the immune system, and to combine this stimulus with other psychological, environmental, or nutritional stressors.
Skateboarding injuries of today
Authors: Forsman L , Eriksson A 
Published: July 2002

Background—Skateboarding injuries have increased with the rise in popularity of the sport, and the injury pattern can be expected to have changed with the development of both skateboard tricks and the materials used for skateboard construction.Objective—To describe the injury pattern of today.Methods—The pattern of injuries, circumstances, and severity were investigated in a study of all 139 people injured in skateboarding accidents during the period 1995–1998 inclusive and admitted to the University Hospital of Umeå. This is the only hospital in the area, serving a population of 135 000.Results—Three of the 139 injured were pedestrians hit by a skateboard rider; the rest were riders. The age range was 7–47 years (mean 16). The severity of the injuries was minor (AIS 1) to moderate (AIS 2); fractures were classified as moderate. The annual number of injuries increased during the study period. Fractures were found in 29% of the casualties, and four children had concussion. The most common fractures were of the ankle and wrist. Older patients had less severe injuries, mainly sprains and soft tissue injuries. Most children were injured while skateboarding on ramps and at arenas; only 12 (9%) were injured while skateboarding on roads. Some 37% of the injuries occurred because of a loss of balance, and 26% because of a failed trick attempt. Falls caused by surface irregularities resulted in the highest proportion of the moderate injuries.Conclusions—Skateboarding should be restricted to supervised skateboard parks, and skateboarders should be required to wear protective gear. These measures would reduce the number of skateboarders injured in motor vehicle collisions, reduce the personal injuries among skateboarders, and reduce the number of pedestrians injured in collisions with skateboarders.
An investigation of the Peutz-Jeghers gene (LKB1) in sporadic breast and colon cancers
Authors: Forster L F , Defres S , Goudie D R , Baty D U , Carey F A 
Published: July 2002

Aims—To explore the role of the Peutz-Jeghers gene (LKB1) in sporadic breast and colon cancers.Methods—Thirty consecutive sporadic carcinomas of the breast and 23 of the colon were selected. DNA was extracted from paraffin wax embedded tissue and analysed for loss of heterozygosity (LOH) at microsatellite markers D19S886 and D19S565 close to the LKB1 gene. Tumours showing LOH were screened for LKB1 mutations by single strand conformational polymorphism (SSCP).Results—Five breast carcinomas showed LOH (21% and 7% of those informative for D19S886 and D19S565, respectively). Five of the colorectal carcinomas showed LOH (15% and 36% of those informative for D19S886 and D19S565, respectively), with one sample showing allele loss with both markers. Screening of these 10 carcinomas by SSCP identified one migrational shift but sequencing revealed an intronic polymorphism only. Therefore, no coding mutations were found in these carcinomas.Conclusions—These findings suggest that although allele loss at the LKB1 locus occurs relatively frequently in sporadic breast and colon cancers, mutations do not seem to be a feature.
Abnormal haemoglobins, Hb Takamatsu and Hb G-Szuhu, detected during the analysis of glycated haemoglobin (HbA1C) by high performance liquid chromatography
Authors: Moriwaki Y , Yamamoto T , Shibutani Y , Harano T , Takahashi S , Hada T 
Published: July 2002

Background—During medical checkups of two unrelated female outpatients during their annual health examination and one male inpatient suffering from cardiac failure the glycated haemoglobin (HbA1C) concentrations measured by high performance liquid chromatography (HPLC) were low, in spite of normal fasting plasma glucose concentrations. However, HbA1Cconcentrations measured by latex immunoagglutination and fructosamine concentrations were within the normal range.Method—Investigations were performed to elucidate the reasons for these discrepancies.Results—Abnormal haemoglobins, Hb Takamatsu and Hb G-Szuhu, were found. The HPLC chromatogram showed an additional peak near HbA1a+b, which resulted in falsely low HbA1Cconcentrations. Isoelectric focusing analysis of the patients' haemoglobin disclosed abnormal haemoglobins, which migrated faster than normal HbA1in the two female patients and slower in the male patient. The cDNA sequence and amino acid analyses of the haemoglobin α-chains and β-chains indicated the presence of the haemoglobin variant β 120 Lys→Gln in the two female patients and β 80 Asn→Lys in the male patient; that is, Hb Takamatsu and Hb G-Szuhu.Conclusions—These cases show how these silent haemoglobin variants can result in falsely low HbA1Cconcentration readings when using HPLC.
Interaction of insulin withBurkholderia pseudomalleimay be caused by a preservative
Authors: Simpson Andrew J H , Wuthiekanun Vanaporn 
Published: July 2002

Aim—To re-examine the previously reported in vitro interaction of insulin withBurkholderia pseudomallei, in the light of a suggestion that the interaction may have resulted from the presence of the preservative m-cresol in commercial preparations.Methods—Broth culture studies ofB pseudomalleiwere performed with and without the addition of m-cresol and various preparations of insulin.Results—Growth ofB pseudomalleiwas inhibited by m-cresol at the concentrations found in pharmaceutical insulin preparations, and by the insulin preparation Humulin R, but not by pure insulin.Conclusions—The results of previous experiments may have been confounded by the presence of the preservativem-cresol.
Issues of consent and the primary-school medical
Authors: Bradley P 
Published: July 2002

This article discusses what level of consent is needed from a child or parent before a primary-school medical can take place (ie where children are aged under 12). It also considers whether there are occasions when a doctor can see a child if the parents have failed to give consent or have explicitly refused consent.Primary-school children are considered incompetent to make decisions about their own medical treatment and so their consent does not need to be gained before a medical takes place, although it is highly desirable to obtain it. However, a doctor cannot justify a decision to see a child purely in terms of the benefit conferred on the child. Parents can be wronged if their wishes are ignored and usually those wishes should be considered overriding. Normally, general consent, which need not be fully informed, is needed before a school medical. However, if a child is considered to be in danger of being harmed significantly or suspected to have a major medical condition, a medical should go ahead regardless of the level of consent obtained from the parent, so that a reasonable standard of health is maintained for the child.
The process of informed consent for urgent abdominal surgery
Authors: Kay R , Siriwardena A K 
Published: July 2002

Objectives—To assess perceptions of the informed consent process in patients undergoing urgent abdominal surgery.Design—A prospective observational study was carried out using structured questionnaire-based interviews. Patients who had undergone urgent abdominal surgery were interviewed in the postoperative period to ascertain their perceptions of the informed consent process. Replies were compared to responses obtained from a control group undergoing elective surgery, to identify factors common to the surgical process and those specific to urgent surgery. Patients' perceptions of received information were also compared to the information perceived to have been provided by the consent obtainers.Setting—Gastrointestinal surgical service of a university teaching hospital.Patients—Seventy-four consecutive patients undergoing urgent abdominal surgery and 80 control patients undergoing elective surgery.Main measurements—Principal outcome measures were patients' perceptions of factors interfering with the ability to give informed consent, assessment of the quality of informed consent and the degree of discussion of the expected outcomes.Results—Forty-nine of the seventy-four (66%) patients undergoing urgent surgery perceived that pain did not affect their ability to give informed consent. Twenty-seven reported an adverse effect of analgesia on the ability to give informed consent. Only 22% of patients undergoing urgent surgery perceived that there had been any discussion of potential side effects and complications of surgery.Conclusion–The majority of patients in this series with acute intra-abdominal surgical conditions perceive that they retain the ability to give informed consent for surgery. There is a need for improved discussion of therapeutic options and likely outcomes.