bluuebunny/crossref_metadata_2025_split huggingface dataset:
Human Herpesvirus 6 Variant A but Not Variant B Induces Fusion from Without in a Variety of Human Cells through a Human Herpesvirus 6 Entry Receptor, CD46
Authors: Mori Yasuko , Seya Tsukasa , Huang Hong Lan , Akkapaiboon Pilailuk , Dhepakson Panadda , Yamanishi Koichi 
Published: July 2002

ABSTRACT
Human herpesvirus 6 (HHV-6) is a lymphotropic betaherpesvirus that productively infects T cells and monocytes. HHV-6 isolates can be differentiated into two groups, variants A and B (HHV-6A and HHV-6B). Here, we show a functional difference between HHV-6A and -6B in that HHV-6A induced syncytium formation of diverse human cells but HHV-6B did not. The syncytium formation induced by HHV-6A was observed 2 h after infection; moreover, it was found in the presence of cycloheximide, indicating that HHV-6A induced fusion from without (FFWO) in the target cells. Furthermore, the fusion event was dependent on the expression of the HHV-6 entry receptor, CD46, on the target cell membrane. In addition, we determined that short consensus repeat 2 (SCR2), -3, and -4 of the CD46 ectodomain were essential for the formation of the virus-induced syncytia. Monoclonal antibodies against glycoproteins B and H of HHV-6A inhibited the fusion event, indicating that the syncytium formation induced by HHV-6A required glycoproteins H and B. These findings suggest that FFWO, which HHV-6A induced in a variety of cell lines, may play an important role in the pathogenesis of HHV-6A, not only in lymphocytes but also in various tissues, because CD46 is expressed ubiquitously in human tissues.
Antiviral Effects of an Iminosugar Derivative on Flavivirus Infections
Authors: Wu Shu-Fen , Lee Chyan-Jang , Liao Ching-Len , Dwek Raymond A. , Zitzmann Nicole , Lin Yi-Ling 
Published: July 2002

ABSTRACT

Endoplasmic reticulum (ER) α-glucosidase inhibitors, which block the trimming step of N-linked glycosylation, have been shown to eliminate the production of several ER-budding viruses. Here we investigated the effects of one such inhibitor,
N
-nonyl-deoxynojirimycin (
N
N-DNJ), a 9-carbon alkyl iminosugar derivative, on infection by Japanese encephalitis virus (JEV) and dengue virus serotype 2 (DEN-2). In the presence of
N
N-DNJ, JEV and DEN-2 infections were suppressed in a dose-dependent manner. This inhibitory effect appeared to influence DEN-2 infection more than JEV infection, since lower concentrations of
N
N-DNJ substantially blocked DEN-2 replication. Secretion of the flaviviral glycoproteins E and NS1 was greatly reduced, and levels of DEN-2 viral RNA replication measured by fluorogenic reverse transcription-PCR were also decreased, by
N
N-DNJ. Notably, the viral glycoproteins, prM, E, and NS1 were found to associate transiently with the ER chaperone calnexin, and this interaction was affected by
N
N-DNJ, suggesting a potential role of calnexin in the folding of flaviviral glycoproteins. Additionally, in a mouse model of lethal challenge by JEV infection, oral delivery of
N
N-DNJ reduced the mortality rate. These findings show that
N
N-DNJ has an antiviral effect on flavivirus infection, likely through interference with virus replication at the posttranslational modification level, occurring mainly in the ER.
Ty1 Defect in Proteolysis at High Temperature
Authors: Lawler Joseph F. , Haeusser Daniel P. , Dull Angie , Boeke Jef D. , Keeney Jill B. 
Published: July 2002

ABSTRACT

Retrotransposition of the Ty1 element of
Saccharomyces cerevisiae
is temperature sensitive. Transposition activity of Ty1 is abolished at temperatures above 34°C. In this report, we show that the major block to transposition at high temperature is the inhibition of processing of the Gag-Pol-p199 polyprotein and the concomitant reduction of reverse transcriptase (RT) activity. Expression of a Ty1 protease construct in
Escherichia coli
shows that protease enzymatic activity is inherently temperature sensitive. In yeast, Gag processing is only partially inhibited at high temperature, while cleavage of the Gag-Pol polyprotein is completely inhibited. Sites of proteolytic processing are differentially susceptible to cleavage during growth at high temperature. Overall levels of the Gag-Pol polyprotein are reduced at high temperature, although the efficiency of the requisite +1 frameshifting event appears to be increased. RT activity is inherently relatively temperature resistant, yet no cDNA is made at high temperature and the amount of RT activity is greatly reduced in virus-like particles formed at high temperature. Taken together, these results suggest that alterations in Ty1 proteins that occur at high temperature affect both protease activity and RT activity, such that Ty1 transposition is abolished.
The Carboxy Terminus of Simian Virus 40 Large T Antigen Is Required To Disrupt the Yeast Cell Cycle
Authors: Fewell Sheara W. , Markle Dena M. , Brodsky Jeffrey L. 
Published: July 2002

ABSTRACT

Wild-type and J domain mutant simian virus 40 large T antigens alter the cell cycle and bud morphology of
Saccharomyces cerevisiae
. In contrast, yeast cells expressing mutant T antigen lacking the carboxy-terminal 150 aa exhibit normal morphology, indicating that this region of T antigen is required for cell cycle disruption.
Performance of population specific job exposure matrices (JEMs): European collaborative analyses on occupational risk factors for chronic obstructive pulmonary disease with job exposure matrices (ECOJEM)
Authors: Le Moual N , Bakke P , Orlowski E , Heederik D , Kromhout H , Kennedy S M , Rijcken B , Kauffmann F 
Published: July 2002

OBJECTIVESTo compare the performance of population specific job exposure matrices (JEMs) and self reported occupational exposure with data on exposure and lung function from three European general populations.METHODSSelf reported occupational exposure (yes or no) and present occupation were recorded in the three general population surveys conducted in France, The Netherlands, and Norway. Analysis was performed on subjects, aged 25–64, who provided good forced expiratory volume in 1 second (FEV1) tracings and whose occupations were performed by at least two people, in the French (6217 men and 5571 women), the Dutch (men from urban (854) and rural (780) areas), and the Norwegian (395 men) surveys. Two population specific JEMs, based on the percentage of subjects who reported themselves exposed in each job, were constructed for each survey and each sex. The first matrix classified jobs into three categories of exposure according to the proportion of subjects who reported themselves exposed in each job (P10–50 JEM, low < 10%, moderate 10–49%, high ⩾ 50%). For the second matrix, a dichotomous variable was constructed to have the same statistical power as the self reported exposure—that is, the exposure prevalence (p) was the same with both exposure assessment methods (Pp JEM). Relations between occupational exposure, as estimated by the two JEMs and self reported exposure, and age, height, city, and smoking adjusted FEV1score were compared.RESULTSSignificant associations between occupational exposure estimated by the population specific JEM and lung function were found in the French and the rural Dutch surveys, whereas no significant relation was found with self reported exposure. In populations with few subjects in most jobs, exposure cannot be estimated with sufficient precision by a population specific JEM, which may explain the lack of relation in the Norwegian and the Dutch (urban area) surveys.CONCLUSIONThe population specific JEM, which was easy to construct and cost little, seemed to perform better than crude self reported exposures, in populations with sufficient numbers of subjects per job.
Exposure-response relations for self reported asthma and rhinitis in bakers
Authors: Brisman Jonas , Järvholm Bengt , Lillienberg Linnéa 
Published: July 2002

OBJECTIVESTo explore relations between two estimates of exposure to inhalable flour dust, and the incidence rates (IRs) of asthma and rhinitis in bakers.METHODSThis was a retrospective cohort study among 2923 bakers. A posted questionnaire registered the disease and work history. For every year, each baker was assigned an estimate of the exposure concentration to inhalable flour dust derived from reported job-tasks and dust measurements. Exposure at onset of disease was expressed as current dust exposure concentration, and as cumulative dose of exposure to dust. A multiple Poisson regression analysis assessed the impacts of the exposure estimates on the IRs of asthma and rhinitis.RESULTSIRs of asthma and rhinitis increased by dust concentration at onset of disease. The IR of asthma for the bakers with highest exposure (dough makers) was 7.3/1000 person-years in men and 6.5 in women and for rhinitis 43.4 and 38.5, respectively. There was a significant association between the dust concentration at onset of disease and the risk for asthma or rhinitis, but not of the cumulative exposure.CONCLUSIONThe risk of asthma seemed to be increased at inhalable dust concentrations ⩾3 mg/m3(dough making or bread forming), whereas the risk of rhinitis was increased at all concentrations ⩾1 mg/m3, indicating an increased risk in all bakery job-tasks. The risks seemed to be less dependent on the cumulative exposure dust than the inhalable dust concentrations.
Relation between immune variables and burnout in a sample of physicians
Authors: Bargellini Annalisa , Barbieri Alberto , Rovesti Sergio , Vivoli Roberto , Roncaglia Roberto , Borella Paola 
Published: July 2002

OBJECTIVESTo evaluate in a group of physicians the relation between burnout, demographic or job characteristics, anxiety, and immune variables.METHODSSeventy one physicians of all grades were recruited among different departments to a cross sectional survey. The Maslach burnout inventory, scales of emotional exhaustion, depersonalisation, and personal accomplishment, the trait scale of anxiety inventory (STAI-Y2), and a questionnaire on personal and professional characteristics were administered. The immune profile included quantitative (number (%) of lymphocytes and subsets) and functional (natural killer cytotoxicity) measures.RESULTSWith a model of stepwise multiple regression analysis, emotional exhaustion was significantly affected by both personal (marital, sex) and job characteristics (qualification, working activity), whereas only patient contact explained a portion of variation in depersonalisation. Furthermore, trait anxiety was found to predict the Maslach burnout inventory scores. After correction for potential confounders, physicians who scored high levels of personal accomplishment showed significantly higher numbers of total lymphocytes, T cells (CD3), T helper cells (CD4), and T suppressor cells (CD8) than those who scored low levels. No other correlation was found between burnout and immune variables.CONCLUSIONSIn our group of relatively young physicians a high degree of personal accomplishment was associated with an increase in the number of peripheral lymphocytes, particularly T subsets. The meaning of this is not clear, although it could be speculated that to evaluate oneself positively, particularly with regard to work with patients in the health services, might help to stimulate the immune system. By contrast, there is no evidence that to work hard, to feel tired from work, and to have a cynical reaction towards patient care is related to immunosuppression.
Modern approaches to blood pressure measurement
Authors: Staessen Jan A , O'Brien Eoin T , Thijs Lutgarde , Fagard Robert H 
Published: July 2002

BACKGROUNDBlood pressure (BP) is usually measured by conventional sphygmomanometry. Although apparently simple, this procedure is fraught with many potential sources of error. This review focuses on two alternative techniques of BP measurement: ambulatory monitoring and self measurement.REVIEWBP values obtained by ambulatory monitoring or self measurement are characterised by high reproducibility, are not subject to digit preference or observer bias, and minimise the transient rise of the blood pressure in response to the surroundings of the clinic or the presence of the observer, the so called white coat effect. For ambulatory monitoring, the upper limits of systolic/diastolic normotension in adults include 130/80 mm Hg for the 24 hour BP and 135/85 and 120/70 mm Hg for the daytime BP and night time BP, respectively. For the the self measured BP these thresholds include 135/85 mm Hg. Automated BP measurement is most useful to identify patients with white coat hypertension. Whether or not white coat hypertension predisposes to sustained hypertension remains debated. However, outcome is better correlated with the ambulatory BP than with the conventional BP. In patients with white coat hypertension, antihypertensive drugs lower the BP in the clinic, but not the ambulatory BP, and also do not improve prognosis. Ambulatory BP monitoring is also better than conventional BP measurement in assessing the effects of treatment. Ambulatory BP monitoring is necessary to diagnose nocturnal hypertension and is especially indicated in patients with borderline hypertension, elderly patients, pregnant women, patients with treatment resistant hypertension, and also in patients with symptoms suggestive of hypotension.CONCLUSIONSThe newer techniques of BP measurement are now well established in clinical research, for diagnosis in clinical practice, and will increasingly make their appearance in occupational and environmental medicine.
Leukaemia mortality in relation to magnetic field exposure: findings from a study of United Kingdom electricity generation and transmission workers, 1973–97
Authors: Harrington J M , Nichols L , Sorahan T , van Tongeren M 
Published: July 2002

OBJECTIVETo investigate whether risks of leukaemia are related to occupational exposure to magnetic fields.METHODSThe mortality experienced by a cohort of 83 997 employees of the former Central Electricity Generating Board of England and Wales was investigated for the period 1973–97. All employees were employed for at least 6 months with some employment in the period 1973–82. Computerised work histories were available for 79 972 study subjects for the period 1971–93. Detailed calculations were performed by others to enable a novel assessment to be made of exposures to magnetic fields. Two analytical approaches were used, indirect standardisation (n=83 997) and Poisson regression (n=79 972).RESULTSBased on serial mortalities for England and Wales, the standardised mortality ratio of 84 for all leukaemias (observed 111, expected 132.3) was similar to that of 83 for all causes (observed 14 845, expected 17 918). No significant positive trends were found for the risks of various types of leukaemia (chronic lymphatic leukaemia, acute myeloid leukaemia, chronic myeloid leukaemia, all leukaemia) either with lifetime cumulative exposure to magnetic fields or with such exposures received in the most recent 5 years.CONCLUSIONSThere are no discernible excess risks of leukaemia as a consequence of occupational exposure to magnetic fields in United Kingdom electricity generation and transmission workers.
Report of occupational asthma due to phytase and β-glucanase: Table 1
Authors: O'Connor T M , Bourke J F , Jones M , Brennan N 
Published: July 2002

OBJECTIVESOccupational asthma is the principal cause of respiratory disease in the workplace. The enzymes phytase and β-glucanase are used in the agricultural industry to optimise the nutritional value of animal feeds. A relation between these enzymes and occupational asthma in a 43 year old man was suspected.METHODSInhalation challenge tests were performed with the enzymes phytase, β-glucanase, and amylase. Skin prick tests were performed with the enzymes diluted to a concentration of 1 mg/ml and 5 mg/ml. Specific IgE to phytase and β-glucanase were measured with a radioallergosorbent test.RESULTSBaseline spirometry values were normal. A histamine challenge test showed bronchial hyperreactivity. Exposure to phytase and β-glucanase led to significant reductions in forced vital capacity and forced expired volume in 1 second. No significant differences were noted after exposure to amylase. Skin tests showed a positive reaction to β-glucanase (5 mm) at a concentration of 1 mg/ml and positive reactions to β-glucanase (7 mm) and phytase (5 mm) at a concentration of 5 mg/ml. Similarly specific IgE was present against both phytase and β-glucanase, at 2.5% and 9.3% binding respectively (2% binding is considered positive).CONCLUSIONSThis is the first description of occupational asthma due to the enzymes phytase and β-glucanase. Their addition to the ever increasing list of substances associated with occupational asthma will have notable implications for those exposed to these enzymes.
Unreliability of cardiothoracic ratio as a marker of left ventricular impairment: comparison with radionuclide ventriculography and echocardiography
Authors: Clark Andrew L , Coats Andrew J S 
Published: July 2002

Abstract

Background
The size of the heart assessed by cardiothoracic ratio on chest radiography is often used as a screening test for the presence of heart failure and for assessing its severity.

Methods
We compared cardiothoracic ratio (CTR), left ventricular ejection fraction (LVEF) from radionuclide ventriculography, and left ventricular dimensions from echocardiography in a population of 91 patients (aged 60.4 (SD 9.6) years) with a diagnosis of chronic heart failure.

Results
There was a weak relation between CTR and LVEF (R=0.33) and fractional shortening from echocardiography (R=0.22). LVEF and fractional shortening correlated more closely (R=0.55). No measure of left ventricular function correlated with exercise capacity as measured by peak oxygen consumption. For the group of patients with a normal fractional shortening (n=17), the left ventricle was dilated in all but two (mean end diastolic dimension 5.9 (0.7) cm). The two with normal dimensions had a low ejection fraction. For the 12 patients with a CTR in the normal range, the left ventricular end diastolic dimension was only slightly smaller than for the rest (6.2 (0.9)v 6.9 (1.2); p=0.045).

Conclusions
Chest radiography is not a reliable indicator of the degree of left ventricular dysfunction. Echocardiography and radionuclide ventriculography are more appropriate investigations for assessing cardiac function.
TWO-STEP ELECTRON BEAM EXCITATION OF Al2O3:Cr BY GALLIUM NITRIDE RECOMBINATION RADIATION
Authors: ZEHE A. , RAMÍrez A. , SEIFERT W. 
Published: July 2002

We report on a two-step excitation process of a GaN/A 2 O 3: Cr specimen by an external electron beam of 30 keV. The epitaxial growth of GaN on the (0001) faces of ruby is described, as well as the experimental technique applied in the excitation and recording of the combined luminescence spectrum. It is known that the spinel and ruby are frequently used as substrate materials for the epitaxial deposition of GaN. At the same time is ruby one of the most useful layer materials with a red emission line λ = 694 nm. Due to its dielectric character, the pumping of ruby is performed usually subjecting it to the light of an intense flash lamp. Electron beam excitation, on the other hand, which could be more powerful, is impaired with electrical insulator material. This discrepancy can be removed by a two-step excitation, where at first the semiconducting GaN-layer, epitaxially grown on a (0001)Al 2 O 3: Cr (ruby) crystal is excited to radiation emission by an external electron beam. The following internal absolption process, by the ruby crystal, of the GaN luminescence radiation provides for the characteristic 2 E to 4 A 2-transition at 1.786 eV. We found a strong and sharp emission line of that photon energy, which additionally displays polarization, typical for the anisotropic uniaxial ruby crystal. Such an indirect electron-beam excitation of ruby allows to generate almost monochromatic red light, and might point into a direction of interesting practical applications.
Effects of resource sharing on circuit delay
Authors: Bhattacharya Subhrajit , Dey Sujit , Breglez Franc 
Published: July 2002

This paper analyzes the effect of resource sharing and assignment on the clock period of the synthesized circuit. The assignment phase assigns or binds operations of the scheduled behavioral description to a set of allocated resources. We focus on control-flow intensive descriptions, characterized by the presence of mutually exclusive paths due to the presence of nested conditional branches and loops.
We show that clustering multiple operations in the same state of the schedule, possibly leading to chaining of functional units (FUs) in the RTL circuit, is an effective way to minimize the total number of clock cycles, and hence total execution time. We present an assignment algorithm that is particularly effective for such design styles by minimizing data chaining and hence the clock period of the circuit, thereby leading to further reduction in total execution time.
Existing resource sharing and assignment approaches for reducing the clock period of the resulting circuit either increase the resource allocation or use faster modules, both leading to leading to larger area requirements. In this paper we show that even when the type of available resource units and the number of resource units of each type is fixed, different assignments may lead to circuits with significant differences in clock period.
We provide a comprehensive analysis of how resource sharing and assignment introduces long paths in the circuit. Based on the analysis, we develop an assignment algorithm that uses a high-level delay estimator to asign operations to a fixed set of available resources so as to minimize the clock period of the resultant circuit, with no or minimal effect on the area of the circuit. Experimental results on several conditional-intensive designs demonstrate the effectiveness of the assignment algorithm.
Data file management in shift-register memories
Authors: Kluge Werner E. 
Published: July 2002

The paper proposes a shift-register memory, structured as a two-dimensional array of uniform shift-register loops which are linked by flow-steering switches, whose switch control scheme is tailored to perform with great efficiency data management operations on sequentially organized files. The memory operates in a linear input/output mode to perform record insertion, deletion, and relocation on an existing file, and in a sublinear mode for rapid internal file movement to expedite file positioning and record retrieval and update operations.
The memory, implemented as a large capacity charge-coupled device or magnetic domain memory, permits efficient data management on very large databases at the level of secondary storage and lends itself to applications as a universal disk replacement, particularly in database computers.
A facility for defining and manipulating generalized data structures
Authors: Claybrook Billy G. 
Published: July 2002

A data structure definition facility (DSDF) is described that provides definitions for several primitive data types, homogeneous and heterogeneous arrays, cells, stacks, queues, trees, and general lists. Each nonprimitive data structure consists of two separate entities—a head and a body. The head contains the entry point(s) to the body of the structure; by treating the head like a cell, the DSDF operations are capable of creating and manipulating very general data structures. A template structure is described that permits data structures to share templates.
The primary objectives of the DSDF are: (1) to develop a definition facility that permits the programmer to explicitly define and manipulate generalized data structures in a consistent manner, (2) to detect mistakes and prevent the programmer from creating (either inadvertently or intentionally) undesirable (or illegal) data structures, (3) to provide a syntactic construction mechanism that separates the implementation of a data structure from its use in the program in which it is defined, and (4) to facilitate the development of reliable software.