PubMed Health⌕ Search

Biomedical subjects

J R Edwards

Publications and source records attributed to J R Edwards.

At least 19 recordsLinked to original sources
PubMed2006

Comparison of sensitivity and specificity in three commercial foot-and-mouth disease virus non-structural protein ELISA kits with swine sera in Taiwan.

Three commercialized ELISA kits for the detection of antibodies to the non-structural proteins (NSPs) of FMD virus were compared, using sera from uninfected, vaccinated, challenged and naturally infected pigs. The kinetics of the antibody response to NSPs was compared on sequential serum samples in swine from challenge studies and outbreaks. The results showed that ELISA A (UBI) and ELISA B (CEDI) had better sensitivity than that of the 3ABC recombinant protein-based ELISA C (Chekit). The peak for detection of antibodies to NSPs in ELISA C was significantly delayed in sera from natural infection and challenged swine as compared to the ELISA A and B. The sensitivity of the three ELISAs gradually declined during the 6-month post-infection as antibodies to NSP decline. ELISA kits A and B detected NSP antibody in 50% of challenged pigs by the 9-10th-day and 7-8th-day post-challenge, respectively. ELISA B and C had better specificity than ELISA A on sequential serum samples obtained from swine immunized with a type O FMD vaccine commercially available in Taiwan. Antibody to NSPs before vaccination was not detected in swine not exposed to FMD virus, however, antibody to NSPs was found in sera of some pigs after vaccination. All assays had significantly lower specificity when testing sera from repeatedly vaccinated sows and finishers in 1997 that were tested after the 1997 FMD outbreak. However, when testing sera from repeatedly vaccinated sows or finishers in 2003-2004, the specificity for ELISAs A, B and C were significantly better than those in 1997. This effect was less marked for ELISA A. The ELISA B was the best test in terms of the highest sensitivity and specificity and the lowest reactivity with residual NSP in vaccinates.

Animals↗
PubMed2006

LIGHT (TNFSF14), a novel mediator of bone resorption, is elevated in rheumatoid arthritis.

OBJECTIVE: Human osteoclast formation from mononuclear phagocyte precursors involves interactions between tumor necrosis factor (TNF) ligand superfamily members and their receptors. LIGHT is a transmembrane protein expressed and shed from the surface of activated T cells. Since activated T cells have been implicated in osteoclastogenesis in rheumatoid arthritis (RA), this study sought to determine whether LIGHT can regulate RANKL/cytokine-induced osteoclast formation, to identify the mechanism by which LIGHT influences osteoclastogenesis, and to investigate the presence of LIGHT in the serum of RA patients. METHODS: The effect of LIGHT on human and murine osteoclast formation was assessed in the presence and absence of neutralizing reagents to known osteoclastogenic factors. Serum levels of LIGHT in RA patients were measured by enzyme-linked immunosorbent assay. RESULTS: In the presence and absence of RANKL, LIGHT induced osteoclast formation from both human peripheral blood mononuclear cells and murine macrophage precursors, in a dose-dependent manner, whereas no inhibition was observed by adding osteoprotegerin, RANK:Fc, TNFalpha, or interleukin-8 or by blocking the LIGHT receptors herpesvirus entry mediator or lymphotoxin beta receptor. However, formation of osteoclasts was significantly decreased by the soluble decoy receptor for LIGHT, DcR3, and by blocking antibodies to the p75 component of the TNF receptor. A significant increase in LIGHT levels in the serum of RA patients compared with normal controls was also noted. CONCLUSION: Our results indicate that LIGHT promotes RANKL-mediated osteoclastogenesis and that it can induce osteoclast formation by a mechanism independent of RANKL. The increased concentration of LIGHT in patients with RA raises the possibility that LIGHT may play a role in immunopathogenic conditions that are associated with localized or systemic bone loss.

Animals↗
PubMed2004

Expression of a lymphatic endothelial cell marker in benign and malignant vascular tumors.

Tumors of endothelial cell origin are relatively common. Soft tissue tumors and numerous subtypes of benign and malignant vascular tumors have been described; the histogenesis of many of these tumors is uncertain, and distinguishing between benign and malignant vascular tumors, some of which express lymphatic endothelial cell markers, can be problematic. In the present study, immunophenotypic expression of a novel hyaluronan receptor (LYVE-1), which is expressed by endothelial cells of normal lymphatic vessels but not blood vessels, was determined in benign and malignant vascular tumors. It was found that, except in lymphangiomas, intramuscular hemangiomas, and Masson's hemangiomas, endothelial cells in benign blood vessel tumors (including capillary and cavernous hemangiomas, glomus tumors, pyogenic granulomas, and epithelioid hemangiomas) were negative for LYVE-1, and that all angiosarcomas and Kaposi's sarcomas were positive for LYVE-1. Expression of LYVE-1 and other lymphatic endothelial cell markers in relatively few vascular neoplasms has implications for the histogenesis of these lesions, and may prove useful in distinguishing angiosarcoma and Kaposi's sarcoma from most common benign vascular tumors.

Biomarkers, Tumor↗
PubMed2004

Strategy for the control of foot-and-mouth disease in Southeast Asia (SEAFMD).

The OIE Southeast Asia Foot-and-Mouth Disease Campaign (SEAFMD) involves the coordinated control of foot-and-mouth disease by eight of the ASEAN countries. A long term vision for SEAFMD has been developed and the core element is a progressive zoning approach to the control and eradication of FMD in the region. This paper describes the current status of FMD in Southeast Asia and progress towards achievement of OIE free zone status for FMD in parts of the Philippines and Malaysia and the initiation of the Malaysia-Thailand-Myanmar (MTM) Peninsular Campaign for FMD Freedom. In mainland Southeast Asia, the progressive zoning approach involves several sub-regional groups working in parallel to oversee the epidemiological and economic studies required to determine the feasibility of the approach. Areas involved include the Lower Mekong Basin, Upper Mekong Basin, parts of Myanmar and the Red River Delta of Vietnam. The paper describes the current usage of vaccines for FMD in Southeast Asia and provides recommendations for their supply and use in the new regional initiatives.

Animals↗
PubMed2002

Secular trend of hospital-acquired candidemia among intensive care unit patients in the United States during 1989-1999.

We describe the annual incidence of primary bloodstream infection (BSI) associated with Candida albicans and common non-albicans species of Candida among patients in intensive care units that participated in the National Nosocomial Infections Surveillance system from 1 January 1989 through 31 December 1999. During the study period, there was a significant decrease in the incidence of C. albicans BSI (P<.001) and a significant increase in the incidence of Candida glabrata BSI (P=.05).

Adult↗
PubMed2001

DNA sequencing using biotinylated dideoxynucleotides and mass spectrometry.

Matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MS) has been explored widely for DNA sequencing. The major requirement for this method is that the DNA sequencing fragments must be free from alkaline and alkaline earth salts as well as other contaminants for accurately measuring the masses of the DNA fragments. We report here the development of a novel MS DNA sequencing method that generates Sanger-sequencing fragments in one tube using biotinylated dideoxynucleotides. The DNA sequencing fragments that carry a biotin at the 3'-end are made free from salts and other components in the sequencing reaction by capture with streptavidin-coated magnetic beads. Only correctly terminated biotinylated DNA fragments are subsequently released and loaded onto a mass spectrometer to obtain accurate DNA sequencing data. Compared with gel electrophoresis-based sequencing systems, MS produces a very high resolution of DNA-sequencing fragments, fast separation on microsecond time scales, and completely eliminates the compressions associated with gel electrophoresis. The high resolution of MS allows accurate mutation and heterozygote detection. This optimized solid-phase DNA-sequencing chemistry plus future improvements in detector sensitivity for large DNA fragments in MS instrumentation will further improve MS for DNA sequencing.

Base Sequence↗
PubMed2001

Surgical site infection (SSI) rates in the United States, 1992-1998: the National Nosocomial Infections Surveillance System basic SSI risk index.

By use of the National Nosocomial Infections Surveillance (NNIS) System's surgical patient surveillance component protocol, the NNIS basic risk index was examined to predict the risk of a surgical site infection (SSI). The NNIS basic SSI risk index is composed of the following criteria: American Society of Anesthesiologists score of 3, 4, or 5; wound class; and duration of surgery. The effect when a laparoscope was used was also determined. Overall, for 34 of the 44 NNIS procedure categories, SSI rates increased significantly (P< .05) with the number of risk factors present. With regard to cholecystectomy and colon surgery, the SSI rate was significantly lower when the procedure was done laparoscopically within each risk index category. With regard to appendectomy and gastric surgery, use of a laparoscope affected SSI rates only when no other risk factors were present. The NNIS basic SSI index is useful for risk adjustment for a wide variety of procedures. For 4 operations, the use of a laparoscope lowered SSI risk, requiring modification of the NNIS basic SSI risk index.

Cross Infection↗
PubMed2001

The effect of vancomycin and third-generation cephalosporins on prevalence of vancomycin-resistant enterococci in 126 U.S. adult intensive care units.

BACKGROUND: Patient-specific risk factors for acquisition of vancomycin-resistant enterococci (VRE) among hospitalized patients are becoming well defined. However, few studies have reported data on the institutional risk factors, including rates of antimicrobial use, that predict rates of VRE. Identifying modifiable institutional factors can advance quality-improvement efforts to minimize hospital-acquired infections with VRE. OBJECTIVE: To determine the independent importance of any association between antimicrobial use and risk factors for nosocomial infection on rates of VRE in intensive care units (ICUs). DESIGN: Prospective ecologic study. SETTING: 126 adult ICUs from 60 U.S. hospitals from January 1996 through July 1999. PATIENTS: All patients admitted to participating ICUs. MEASUREMENTS: Monthly use of antimicrobial agents (defined daily doses per 1000 patient-days), nosocomial infection rates, and susceptibilities of all tested enterococci isolated from clinical cultures. RESULTS: Prevalence of VRE (median, 10%; range, 0% to 59%) varied by type of ICU and by teaching status and size of the hospital. Prevalence of VRE was strongly associated with VRE prevalence among inpatient non-ICU areas and outpatient areas in the hospital, ventilator-days per 1000 patient-days, and rate of parenteral vancomycin use. In a weighted linear regression model controlling for type of ICU and rates of VRE among non-ICU inpatient areas, rates of vancomycin use (P < 0.001) and third-generation cephalosporin use (P = 0.02) were independently associated with VRE prevalence. CONCLUSIONS: Higher rates of vancomycin or third-generation cephalosporin use were associated with increased prevalence of VRE, independent of other ICU characteristics and the endemic VRE prevalence elsewhere in the hospital. Decreasing the use rates of these antimicrobial agents could reduce rates of VRE in ICUs.

Anti-Bacterial Agents↗
PubMed2001

Antimicrobial resistance prevalence rates in hospital antibiograms reflect prevalence rates among pathogens associated with hospital-acquired infections.

To determine whether routine antibiograms (summaries reporting resistance of all tested isolates) reflect resistance rates among pathogens associated with hospital-acquired infections, we compared data collected from 2 different surveillance components in the same 166 intensive care units (ICUs). ICUs reported data during the same months to both the infection-based surveillance and the laboratory-based surveillance. Paired comparisons of the percentage of isolates resistant were made between systems within each ICU. No significant differences existed (P>.05) between the percentage of isolates resistant from the infection-based system and laboratory-based system for all antimicrobial-resistant organisms studied, except methicillin resistance in Staphylococcus species. The mean difference in percentage resistance was higher from the infection-based system than the laboratory-based system for S. aureus (mean difference, +8%, P<.001) and coagulase-negative staphylococci (mean difference, +9%, P<.001). Overall, hospital antibiograms reflected susceptibility patterns among isolates associated with hospital-acquired infections. Hospital antibiograms may underestimate the relative frequency of methicillin resistance among Staphylococcus species when associated with hospital-acquired infections.

Cross Infection↗
PubMed2001

Impact of donor type on outcome of bone marrow transplantation for Wiskott-Aldrich syndrome: collaborative study of the International Bone Marrow Transplant Registry and the National Marrow Donor Program.

Human leukocyte antigen (HLA)-identical sibling bone marrow transplantation is an effective treatment for Wiskott-Aldrich syndrome. However, most children with this disease lack such donors and many patients receive transplants from alternative donors. This study compared outcomes of HLA-identical sibling, other related donor, and unrelated donor transplantation for Wiskott-Aldrich syndrome. The outcome of 170 transplantations for Wiskott-Aldrich syndrome, from 1968 to 1996, reported to the International Bone Marrow Transplant Registry and/or National Marrow Donor Program were assessed. Fifty-five were from HLA-identical sibling donors, 48 from other relatives, and 67 from unrelated donors. Multivariate proportional hazards regression was used to compare outcome by donor type and identify other prognostic factors. Most transplant recipients were younger than 5 years (79%), had a pretransplantation performance score greater than or equal to 90% (63%), received pretransplantation preparative regimens without radiation (82%), and had non-T-cell-depleted grafts (77%). Eighty percent received their transplant after 1986. The 5-year probability of survival (95% confidence interval) for all subjects was 70% (63%-77%). Probabilities differed by donor type: 87% (74%-93%) with HLA-identical sibling donors, 52% (37%-65%) with other related donors, and 71% (58%-80%) with unrelated donors (P =.0006). Multivariate analysis indicated significantly lower survival using related donors other than HLA-identical siblings (P =.0004) or unrelated donors in boys older than 5 years (P =.0001), compared to HLA-identical sibling transplants. Boys receiving an unrelated donor transplant before age 5 had survivals similar to those receiving HLA-identical sibling transplants. The best transplantation outcomes in Wiskott-Aldrich syndrome are achieved with HLA-identical sibling donors. Equivalent survivals are possible with unrelated donors in young children.

Actuarial Analysis↗
PubMed2001

A study of gas-phase mercury speciation using detailed chemical kinetics.

Mercury speciation in combustion-generated flue gas was modeled using a detailed chemical mechanism consisting of 60 reactions and 21 species. This speciation model accounts for the chlorination and oxidation of key flue-gas components, including elemental mercury (Hg0). Results indicated that the performance of the model is very sensitive to temperature. Starting with pure HCl, for lower reactor temperatures (less than approximately 630 degrees C), the model produced only trace amounts of atomic and molecular chlorine (Cl and Cl2), leading to a drastic underprediction of Hg chlorination compared with experimental data. For higher reactor temperatures, model predictions were in good accord with experimental data. For conditions that produce an excess of Cl and Cl2 relative to Hg, chlorination of Hg is determined by the competing influences of the initiation step, Hg + Cl = HgCl, and the Cl recombination reaction, 2Cl = Cl2. If the Cl recombination reaction is faster, Hg chlorination will eventually be dictated by the slower pathway Hg + Cl2 = HgCl2.

Air Pollution↗
PubMed2000

High-dose chemotherapy and autologous stem-cell transplantation for ovarian cancer: an autologous blood and marrow transplant registry report.

BACKGROUND: Autologous transplantation is increasingly used to treat epithelial ovarian cancer. However, it is not clear which patients may benefit. OBJECTIVE: To determine overall and progression-free survival and factors associated with favorable outcome after autotransplantation for ovarian cancer. DESIGN: Observational cohort study. SETTING: 57 centers reporting to the Autologous Blood and Marrow Transplant Registry (ABMTR). PATIENTS: 421 women who received transplants between 1989 and 1996. INTERVENTIONS: High-dose chemotherapy using diverse regimens with hematopoietic stem-cell rescue. MEASUREMENTS: Primary outcomes were progression-free survival and overall survival. Multivariate analyses using Cox proportional hazards regression considered the following factors: age, Karnofsky performance score, initial stage, histologic characteristics, previous therapy, remission status, extent of disease, graft source, transplant regimen, and year of transplantation. RESULTS: Most patients had extensive previous chemotherapy. Forty-one percent had platinum-resistant tumors, and 38% had tumors at least 1 cm in diameter. Only 34 patients (8%) received transplants as part of initial therapy. The probability of death within 100 days was 11% (95% CI, 8% to 14%). Two-year progression-free survival was 12% (CI, 9% to 16%), and 2-year overall survival was 35% (CI, 30% to 41%). Younger age, Karnofsky performance score of at least 90%, non-clear-cell disease, remission at transplantation, and platinum sensitivity were associated with better outcomes. Progression-free and overall survival were 22% (CI, 12% to 33%) and 55% (CI, 42% to 66%), respectively, for women with a high Karnofsky performance score and non-clear-cell, platinum-sensitive tumors. CONCLUSIONS: Some subgroups of patients with ovarian cancer seem to have good outcomes after autotransplantation, although several biases may have affected these observations. Phase III trials are needed to compare such outcomes with outcomes of conventional chemotherapy.

Age Factors↗
PubMed2000

Time course for cryoprotectant synthesis in the freeze-tolerant chorus frog, Pseudacris triseriata.

Increases in liver glycogen phosphorylase activity, along with inhibition of glycogen synthetase and phosphofructokinase-1, are associated with elevated cryoprotectant (glucose) levels during freezing in some freeze-tolerant anurans. In contrast, freeze-tolerant chorus frogs, Pseudacris triseriata, accumulate glucose during freezing but exhibit no increase in phosphorylase activity following 24-h freezing bouts. In the present study, chorus frogs were frozen for 5- and 30-min and 2- and 24-h durations. After freezing, glucose, glycogen, and glycogen phosphorylase and synthetase activities were measured in leg muscle and liver to determine if enzyme activities varied over shorter freezing durations, along with glucose accumulation. Liver and muscle glucose levels rose significantly (5-12-fold) during freezing. Glycogen showed no significant temporal variation in liver, but in muscle, glycogen was significantly elevated after 24 h of freezing relative to 5 and 30 min-frozen treatments. Hepatic phosphorylase a and total phosphorylase activities, as well as the percent of the enzyme in the active form, showed no significant temporal variation following freezing. Muscle phosphorylase a activity and percent active form increased significantly after 24 h of freezing, suggesting some enhancement of enzyme function following freezing in muscle. However, the significance of this enhanced activity is uncertain because of the concurrent increase in muscle glycogen with freezing. Neither glucose 6-phosphate independent (I) nor total glycogen synthetase activities were reduced in liver or muscle during freezing. Thus, chorus frogs displayed typical cryoprotectant accumulation compared with other freeze-tolerant anurans, but freezing did not significantly alter activities of hepatic enzymes associated with glycogen metabolism.

Adaptation, Physiological↗
PubMed2000

The extent and impact of sheep pox and goat pox in the state of Maharashtra, India.

A survey of sheep and goat producers in the state of Maharashtra, India, was undertaken to ascertain the extent and economic impact of sheep pox and goat pox (SGP). One thousand one hundred and sixteen owners were interviewed. Eighty owners (7.2%) reported that they had experienced an outbreak of the disease in the previous 6 years. The results showed that, while producers ranked SGP below other infectious diseases such as foot-and-mouth disease, rinderpest and enterotoxaemia, when SGP occurred it had a major impact, with average morbidity and mortality rates of 63.5% and 49.5%, respectively. Modelling studies suggested it would take about 6 years for a flock or herd to recover from an outbreak, with average annual losses in income of 30-43%, depending on flock type and the owner's actions. Statewide, it is estimated that around 5000 flocks and herds are affected by SGP annually in Maharashtra, costing up to INR 107.5 million. The highest losses occurred in the Aurangabad region.

Animal Husbandry↗
PubMed2000

The nature and outcomes of work: a replication and extension of interdisciplinary work-design research.

Research into the changing nature of work requires comprehensive models of work design. One such model is the interdisciplinary framework (M. A. Campion, 1988), which integrates 4 work-design approaches (motivational, mechanistic, biological, perceptual-motor) and links each approach to specific outcomes. Unfortunately, studies of this framework have used methods that disregard measurement error, overlook dimensions within each work-design approach, and treat each approach and outcome separately. This study reanalyzes data from M. A. Campion (1988), using structural equation models that incorporate measurement error, specify multiple dimensions for each work-design approach, and examine the work-design approaches and outcomes jointly. Results show that previous studies underestimate relationships between work-design approaches and outcomes and that dimensions within each approach exhibit relationships with outcomes that differ in magnitude and direction.

Data Collection↗
PubMed2000

On the nature and direction of relationships between constructs and measures.

Theory development typically focuses on relationships among theoretical constructs, placing little emphasis on relationships between constructs and measures. In most cases, constructs are treated as causes of their measures. However, this causal flow is sometimes reversed, such that measures are viewed as causes of constructs. Procedures have been developed to identify and estimate models that specify constructs as causes or effects of measures. However, these procedures provide little guidance for determining a priori whether constructs should be specified as causes or effects of their measures. Moreover, these procedures address few of the possible causal structures by which constructs and measures may be related. This article develops principles for specifying the direction and structure of relationships between constructs and measures. These principles are illustrated using examples from psychological, sociological, and organizational research.

Causality↗