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J Wright

Publications and source records attributed to J Wright.

At least 19 recordsLinked to original sources
PubMed1999

Environmental engineering: energy value of replacing waste disposal with resource recovery

Although in the past, environmental engineering has been primarily concerned with waste disposal, the focus of the field is now shifting toward viewing wastes as potential resources. Because reclamation usually consumes less energy than producing new materials, increasing reclamation not only reduces pollution but saves energy. Technological innovations contributing to this shift are summarized here, and are variously classified as emerging technologies or research topics, as either new departures or incremental improvements, and as opportunistic innovations, or examples of a unifying strategy. Both liquid and solid waste examples are given, such as a recent discovery of effects in disinfecting microfiltered reclaimed wastewater with ultraviolet light. In addition to its value in reducing pollution and conserving energy, this reorientation of environmental engineering could contribute to a more general shift toward greater cooperation among organizations dealing with the environment.

Journal Article↗
PubMed1999

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Journal Article↗
PubMed1999

Assessment of an automated solid phase competitive fluoroimmunoassay for benzoylecgonine in untreated urine.

A new solid phase fluoroimmunoassay using a fully automated flow fluorometer adapted for urinalysis of drug metabolites is described. Fluorescein-conjugated benzoylecgonine (FL-BE) and monoclonal antibodies (mAb) against benzoylecgonine (BE) were the reagents used for demonstration. The solid phase consisted of anti-BE mAbs immobilized on the surface of polymethyl methacrylate (PMMA) beads. Free BE in solution competed with FL-BE and reduced bead-bound fluorescence in a concentration-dependent manner. The binding of FL-BE to the anti-BE mAb reached steady-state within minutes. FL-BE was not bound by uncoated beads nor beads coated with non-specific proteins or IgG. The signal-to-noise ratio was 33, and the sensitivity of the assay was 2 ng ml(-1) for BE. The effective concentration of BE was 1 to 100 ng ml(-1), with an IC50 value of 12 ng ml(-1). The mAb showed equal affinities for BE, cocaine, and cocaethylene, but a five order-of-magnitude lower affinity for ecgonine and ecgonine methylester. In a double-blind comparison using clinical urine samples, the data from this single-step competitive assay had excellent agreement with results obtained using a fiber-optic biosensor (FOB), and the EMIT assay performed commercially. The assay provided kinetic data rapidly and can be used to detect small analytes for which antibodies and fluorescein conjugates are available. The affinity of the mAb for FL-BE, calculated from kinetic analysis of the time course of the on and off reaction, was 2.25 x 10(-9) M.

Antibody Affinity↗
PubMed1999

Immunogenicity and protective efficacy of a gE, gG and US2 gene-deleted bovine herpesvirus-1 (BHV-1) vaccine.

The efficacy and safety of a gene-deleted bovine herpesvirus-1 (BHV-1) vaccine was determined in a bovine herpesvirus challenge trial in calves. Three different doses of the vaccine were administered intramuscularly at 10(5), 10(6) and 10(7) PFU/ml and compared to a commercial vaccine and non vaccinated control calves. Challenge was performed by intranasal aerosolization with the Cooper strain of BHV-1 (3 x 10(4) PFU/ml). The non-vaccinated calves shed significantly (P < 0.05) more virus than all other groups on days 4, 8 and 10 post challenge. By day 14 post challenge, antibody titers for BHV-1 of calves vaccinated with 10(7) PFU/ml were significantly (P < 0.05) higher than the commercial or non-vaccinated calves. Clinical scores of non-vaccinated calves were significantly (P < 0.05) higher than all other groups on days 4-14 post challenge. With both radioimmunoprecipitation and competitive enzyme-linked immunosorbent assays (C-ELISA), calves in the gene-deleted vaccine groups mounted comparable specific responses against gB, gC and gD post vaccination as calves in the commercial vaccine group, but in a dose dependent manner. These data suggest that the gene-deleted BHV-1 vaccine tested may be used as an effective vaccine in controlling BHV-1 infections.

Administration, Intranasal↗
PubMed1999

Occult vitamin D deficiency in postmenopausal US women with acute hip fracture.

CONTEXT: Low vitamin D levels may contribute to hip fractures in women, although limited data are available on vitamin D levels in US women admitted with acute hip fractures. OBJECTIVE: To determine whether postmenopausal women with hip fractures have low vitamin D and high parathyroid hormone levels compared with nonosteoporotic and osteoporotic women admitted for elective joint replacement. DESIGN: Comparative case series conducted between January 1995 and June 1998. SETTING AND PATIENTS: Ninety-eight postmenopausal community-dwelling women with no secondary causes of bone loss admitted for hip replacement, of whom 30 women had acute hip fractures and 68 women were admitted for elective joint replacement. Of the women admitted for elective joint replacement, 17 had osteoporosis and 51 did not. Women with comorbid conditions or who were taking medications that affect bone density and turnover were excluded. MAIN OUTCOME MEASURES: Primary measures were levels of vitamin D and parathyroid hormone; secondary measures were body composition and markers of bone turnover. RESULTS: Women with hip fractures had lower levels of 25-hydroxyvitamin D than women without osteoporosis admitted for elective joint replacement (P = .02) and than women with osteoporosis admitted for elective joint replacement (P = .01) (medians, 32.4, 49.9, and 55.0 nmol/L, respectively; comparisons adjusted for age and estrogen intake). Parathyroid hormone levels were higher in women with fractures than women in the nonosteoporotic control group (P<.001) or than elective osteoporotic women (P = .001) (medians, 5.58, 3.26, and 3.79 pmol/L, respectively; comparisons adjusted for age and estrogen intake). Fifteen patients (50.0%) with hip fractures had deficient vitamin D levels (< or =30.0 nmol/L) and 11 (36.7%) had a parathyroid hormone level greater than 6.84 pmol/L. Levels of N-telopeptide, a marker of bone resorption, were greater in the women with hip fractures than in the elective nonosteoporotic controls (P = .004). CONCLUSIONS: Postmenopausal community-living women who presented with hip fracture showed occult vitamin D deficiency. Repletion of vitamin D and suppression of parathyroid hormone at the time of fracture may reduce future fracture risk and facilitate hip fracture repair. Because vitamin D deficiency is preventable, heightened awareness is necessary to ensure adequate vitamin D nutrition, particularly in northern latitudes.

Aged↗
PubMed1999

The neurochip: a new multielectrode device for stimulating and recording from cultured neurons.

The neurochip is a silicon micromachined device upon which cultured mammalian neurons can be continuously and individually monitored and stimulated. The neurochip is based upon a 4 x 4 array of metal electrodes, each of which has a caged well structure designed to hold a single mature cell body while permitting normal outgrowth of neural processes. We demonstrate that this device is capable of maintaining cell survival, and that the electrodes can both record and stimulate electrical activity in individual cells with no crosstalk between channels.

Algorithms↗
PubMed1999

Team effectiveness: beyond skills and cognitive ability.

On the basis of job analysis results, the validity of using measures of general cognitive ability, job-specific skills, and personality traits jointly at both the individual level and the group level to predict the performance of 79 four-person, human resource work teams was evaluated. Team member trait and job skill scores were aggregated with a conjunctive model of task performance. At the individual level of analysis, measures of personality (i.e., Agreeableness and Conscientiousness) predicted peer ratings of team member performance beyond measures of job-specific skills and general cognitive ability. Similarly, at the group level of analysis, both Agreeableness and Conscientiousness predicted supervisor ratings of work team performance, objective measures of work team accuracy, and work completed. At both the individual and group levels, the trait of Agreeableness predicted Interpersonal Skills.

Adult↗
PubMed1999

Inhibition of carbohydrate-mediated glucagon-like peptide-1 (7-36)amide secretion by circulating non-esterified fatty acids.

Two studies were performed to assess the entero-insular axis in simple obesity and the possible effect of variations in the level of circulating non-esterified fatty acids (NEFA) on one of the components of the entero-insular axis, glucagon-like peptide-1 [(7-36) amide]. In the first study, we compared the entero-pancreatic hormone response to oral carbohydrate in obese and lean women. Obese subjects demonstrated hyperinsulinaemia and impaired glucose tolerance but this was not associated with an increased secretion of either glucose-dependent insulinotropic polypeptide or glucagon-like peptide-1 (GLP-1). These findings therefore provide no support for the hypothesis that overactivity of the entero-insular axis contributes to the hyperinsulinaemia seen in obesity. Indeed, the plasma GLP-1 response to carbohydrate was markedly attenuated in obese subjects, confirming previous observations. In the second study, in which carbohydrate-stimulated GLP-1 responses were again evaluated in obese and lean women, circulating NEFA levels were modulated using either heparin (to increase serum NEFA) or acipimox (to reduce serum NEFA). Treatment with acipimox resulted in complete suppression of NEFA levels and in a markedly higher GLP-1 response than the response to carbohydrate alone or to carbohydrate plus heparin. We suggest that higher fasting and postprandial NEFA levels in obesity may tonically inhibit nutrient-mediated GLP-1 secretion, and that this results in attenuation of the GLP-1 response to carbohydrate. However, although serum NEFA levels post-acipimox were similarly suppressed in both lean and obese subjects, the GLP-1 response was again significantly lower in obese subjects, suggesting the possibility of an intrinsic defect of GLP-1 secretion in obesity. The reduction of GLP-1 levels in obesity may be important both in relation to its insulinotropic effect and to its postulated role as a satiety factor.

Adult↗
PubMed1999

The effect of circulating non-esterified fatty acids on the entero-insular axis.

BACKGROUND: Circulating non-esterified fatty acids (NEFAs) have been causally associated with impairment of glucose metabolism, although their effect on the entero-insular axis, either in obesity or health, is unknown. MATERIALS AND METHODS: Glucose, insulin, glucagon-like peptide-1 (7-36 amide) (GLP-1) and glucose-dependent insulinotropic polypeptide (GIP) responses to 100 g of carbohydrate in 400 mL water were evaluated during simultaneous modulation of circulating non-esterified fatty acids (NEFAs). A total of 10,000 units of heparin (to increase serum NEFAs) and 500 mg of acipimox (2 h before oral carbohydrate ingestion to reduce serum NEFAs) were administered to seven obese [mean +/- SEM: age 40 +/- 3.7 years; body mass index (BMI) 38.9 +/- 2.1 kg m-2] and seven lean (age 39.6 +/- 3.6 years; BMI 22.4 +/- 0.4 kg m-2) women. RESULTS: Higher fasting levels and post-heparin total integrated NEFAs (P < 0.05) and glycerol (P < 0.05) responses were seen in the obese than in the lean group. Incremental integrated GLP-1 responses to oral carbohydrate post-heparin in lean (P < 0.01) and obese (P < 0.05) subjects were significantly lower than after acipimox. Total integrated GIP (P < 0.05) and glucose (P < 0.01) responses were higher post heparin than after acipimox in obese subjects only. CONCLUSION: The inverse relationship in GIP and GLP-1 responses in the obese group after modulation of NEFAs indicates that reciprocal changes between these two hormones may exist to ensure constancy of B-cell stimulation. Our results suggest that in obese subjects compensatory secretion of GIP was incomplete and could not prevent impairment in glucose tolerance after heparin-induced rise in NEFAs. These results may be important in understanding the role of the insulinotropic hormones in carbohydrate metabolism characterized by high NEFA levels such as obesity and diabetes mellitus.

Adult↗
PubMed1999

Seasonal variation of Campylobacter types from human cases, veterinary cases, raw chicken, milk and water.

During August 1996 (winter) and February 1997 (summer), a total of 180 Campylobacter isolates from a restricted geographical area were obtained from human and veterinary cases, raw milk and chicken, and untreated water. Isolates were typed by Penner serotyping and pulsed-field gel electrophoresis (PFGE) of restriction enzyme-produced DNA fragments. Differences were noted between the August and February serotypes with the most, and fourth most frequently isolated serotypes in February being completely absent in August. Two other serotypes were more frequently found in the February isolates, while the reverse was true for two others. In contrast to the serotyping data, one PFGE restriction profile type was dominant in both seasons, and the pattern of distribution of isolates among the other restriction patterns was similar. Five groups of isolates in each month were indistinguishable by both typing methods. Only one group was common to both months. Another group, which was absent in August, dominated the February isolates. Marked differences in the types isolated in the two seasons were therefore evident. Some isolates from human cases were indistinguishable from others isolated from water and raw chicken, indicating possible routes of infection for humans.

Animals↗
PubMed1999

Validation of antroduodenal motility measurements made by echo-planar magnetic resonance imaging.

Echo planar imaging, a development of magnetic resonance imaging, can produce snapshot images of the stomach and antroduodenal segment in as little as 64 msec and can be more useful than conventional techniques when assessing motility. The aim of this study was to compare antroduodenal motility measured by simultaneous perfused tube manometry and echo planar imaging. Ten volunteers were studied following the ingestion of 500 mL water or 500 mL porridge. Antroduodenal images, with acquisition times of 130 msec, were taken at 3-sec intervals, synchronized with motility traces and presented as a split-screen video. This allowed direct visual comparison of gastric wall movement and motility to be made. Contractions were confined to either the stomach or the duodenum or propagated across the antroduodenal segment. Over 4550 images were available for analysis. A larger number of propagated contractions were recorded with echo planar imaging in both water (P = 0.03) and food (P = 0.02) groups, whereas manometry detected a greater number of isolated duodenal pressure waves (P = 0.005). The contraction rate for water and food studies was similar, but direct visualization indicated that the manometric technique under-detected propagated events. The ability of echo planar imaging to record antroduodenal contractile activity provides a new insight into the role of occlusive and nonocclusive contractions during gastric emptying.

Adolescent↗
PubMed1999

Patient Outcomes Research Teams: contribution to outcomes and effectiveness research.

This paper describes the key methodological and substantive findings of Patient Outcomes Research Teams, the first outcomes and effectiveness research centers funded by the Agency for Health Care Policy and Research. Patient Outcomes Research Teams contributed to our increased understanding of how to perform meta analysis on nontrial data, use administrative data to characterize patterns of care, develop general and disease-specific outcome measures, and disseminate important outcome information to patients and physicians to reduce practice variation. Patient Outcomes Research Teams also influenced the development of outcomes measurement in the private sector.

Health Services Research↗
PubMed1999

Role of neutrophils and alpha1-antitrypsin in coal- and silica-induced connective tissue breakdown.

Mineral dusts produce emphysema, and administration of dust to rats results in the rapid appearance of desmosine and hydroxyproline in lavage fluid, confirming that dusts directly induce connective tissue breakdown. To examine the role of neutrophils and alpha1-antitrypsin (alpha1-AT) in this process, we instilled silica or coal into normal rats or rats that had been pretreated with antiserum against neutrophils. One day after dust exposure, lavage fluid neutrophils and desmosine and hydroxyproline levels were all elevated; treatment with antiserum against neutrophils reduced neutrophils by 75%, desmosine by 40-50%, and hydroxyproline by 25%. By 7 days, lavage fluid neutrophils and desmosine level had decreased, whereas macrophages and hydroxyproline level had increased. By ELISA analysis, lavage fluid alpha1-AT levels were increased four- to eightfold at both times. On Western blot, some of the alpha1-AT appeared as degraded fragments, and by HPLC analysis, 5-10% of the methionine residues were oxidized. At both times, lavage fluid exhibited considerably elevated serine elastase inhibitory capacity and also showed elevations in metalloelastase activity. We conclude that, in this model, connective tissue breakdown is initially driven largely by neutrophil-derived proteases and that markedly elevated levels of functional alpha1-AT do not prevent breakdown, thus providing in vivo support for the concept of quantum proteolysis proposed by Liou and Campbell (T. G. Liou and E. J. Campbell. Biochemistry 34: 16171-16177, 1995). Macrophage-derived proteases may be of increasing importance over time, especially in coal-treated animals.

Animals↗
PubMed1999

Evidence-based guidelines for early stroke management.

Stroke disease is the commonest neurological emergency encountered by the junior medical team. We have reviewed the literature to produce a series of substantiated guidelines to assist the admitting doctor in managing early stroke care optimally.

Aged↗
PubMed1999

Carboplatin and paclitaxel, alone and in combination: dose escalation, measurement of renal function, and role of the p53 tumor suppressor gene.

In this pharmacokinetic and dose-escalation study of the carboplatin/paclitaxel (Taxol; Bristol-Myers Squibb Company, Princeton, NJ) combination, patients were randomly assigned to receive paclitaxel either as a 1-hour or a 3-hour infusion. The 1-hour infusion was feasible, with maximum tolerated doses similar to those previously reported for a 3-hour infusion. Using patients' age, height, plasma creatinine, and plasma creatine kinase provided an improved estimate of the glomerular filtration rate compared with the more traditional creatinine-based formulas according to population analysis of data derived from glomerular filtration rate estimates performed by an isotope method. Studies of the p53 gene sequence of ovarian tumors at diagnosis suggest that p53 mutations are a potent predictor of response to subsequent treatment with carboplatin.

Antineoplastic Agents, Phytogenic↗