Biomedical subjects

M Campbell

Publications and source records attributed to M Campbell.

At least 55 records · Page 3Linked to original sources

PubMed2005

Serologic responses, biosafety and clearance of four dosages of Brucella abortus strain RB51 in 6-10 months old water buffalo (Bubalus bubalis).

Thirty water buffalo were obtained from a brucellosis-free farm in order to evaluate antibody responses, bacterial clearance and safety to Brucella abortus strain RB51 vaccine in a dose response study. The animals were randomly divided into five treatment groups. Groups I-V received the recommended dose of RB51 vaccine (RD) once, RD twice 4 weeks apart, double RD once, double RD twice 4 weeks apart and saline once, respectively. Antibody responses to RB51 were monitored at 2, 4, 6, 8, 10, 12, 16 18, 22, 24 and 27 post-initial-inoculation weeks (PIW). Clearance of RB51 from the prescapular lymph node was evaluated at 2, 4, 6, 12, 18 and 24 PIW for groups 1, III and V and at 6, 8, 10, 16, 22 and 27 PIW for groups II and IV. To evaluate shedding of the RB51 strain, nasal, conjunctival, vaginal or preputial swabs were taken from all experimental animals at 1, 2, 3, 4, 6, 8 and 12 PIW. Sera taken at all PIW were negative for field strain B. abortus by both the buffered plate agglutination test (BPAT) and competitive enzyme-linked immunosorbent assay (c-ELISA). Antibody responses to RB51 were demonstrated in all vaccinates but not in the controls, up to 12 PIW, by complement fixation test (CFT) and the dot-blot assay with an 83.7% agreement for both tests. Clearance of RB51 occurred between 6 and 12 PIW in group I but less than 2 weeks after booster vaccinations in groups II and IV and between 4 and 6 PIW in group III. RB51 was not recovered at any time from swabs obtained from either RB51-vaccinates or non-vaccinates. The results of this study indicate that serologic responses to RB51 vaccination can be monitored by both CFT and dot-blot assay in water buffalo. Our data also indicates that RB51 vaccination does not interfere with brucellosis sero-surveillance and is safe (no serological and bacteriological evidence of spread to non-vaccinates, no adverse clinical signs or detectable abnormalities on haematology and serum biochemistry) for use in water buffalo.

Agglutination Tests↗

PubMed2005

Search for long-lived doubly charged Higgs bosons in pp collisions at sqrt[s] = 1.96 TeV.

We present a search for long-lived doubly charged Higgs bosons (H(+/- +/-)), with signatures of high ionization energy loss and muonlike penetration. We use 292 pb(-1) of data collected in pp collisions at sqrt[s] = 1.96 TeV by the CDF II detector at the Fermilab Tevatron. Observing no evidence of long-lived doubly charged particle production, we exclude H(+/- +/-)(L) and H(+/- +/-)(R) bosons with masses below 133 GeV/c(2) and 109 GeV/c(2), respectively. In the degenerate case we exclude H(+/- +/-) mass below 146 GeV/c(2). All limits are quoted at the 95% confidence level.

Journal Article↗

PubMed2005

Search for Higgs bosons decaying into bb and produced in association with a vector boson in pp collisions at square root of s = 1.8 TeV.

We present a new search for H0V production, where H0 is a scalar Higgs boson decaying into bb with branching ratio beta, and V is a Z0 boson decaying into e+e-, mu+mu-, or nunu. This search is then combined with previous searches for H0V where V is a W+/- boson or a hadronically decaying Z0. The data sample consists of 106 +/- 4 pb(-1) of pp collisions at square root of s = 1.8 TeV accumulated by the Collider Detector at Fermilab. Observing no evidence of a signal, we set 95% Bayesian credibility level upper limits on sigma(pp --> H0V) x beta. For H0 masses of 90, 110, and 130 GeV/c2, the limits are 7.8, 7.2, and 6.6 pb, respectively.

Journal Article↗

PubMed2005

Cellulose, modified cellulose and synthetic membranes in the haemodialysis of patients with end-stage renal disease.

BACKGROUND: When the kidney fails the blood-borne metabolites of protein breakdown and water cannot be excreted. The principle of haemodialysis is that such substances can be removed when blood is passed over a semipermeable membrane. Natural membrane materials include cellulose or modified cellulose, more recently various synthetic membranes have been developed. Synthetic membranes are regarded as being more "biocompatible" in that they incite less of an immune response than cellulose-based membranes. OBJECTIVES: To assess the effects of different haemodialysis membrane material in patients with end-stage renal disease (ESRD). SEARCH STRATEGY: We searched MEDLINE, EMBASE, PreMEDLINE, HealthStar CINAHL, the Cochrane Central Register of Controlled Trials (CENTRAL), Biosis, SIGLE, CRIB, UK National Research Register and reference lists of relevant articles. We contacted biomedical companies, known investigators and handsearched selected journals and conference proceedings. Date of most recent search: June 2004. SELECTION CRITERIA: All randomised controlled trials (RCTs) or quasi-RCTs comparing different haemodialysis membrane material in patients with ESRD. DATA COLLECTION AND ANALYSIS: Two reviewers independently assessed the methodological quality of studies. Data was abstracted onto a standard form by one reviewer and checked by another. Relative Risk (RR) and weighted mean difference (WMD) with 95% confidence intervals (CI)) MAIN RESULTS: Thirty two studies were identified. Pre-dialysis ss(2) microglobulin concentrations were not significantly lower in patients treated with synthetic membranes (WMD -14.67, 95% CI -33.10 to 4.05). When analysed for change in ss(2) microglobulin, a fall was only noted with high-flux membranes. The incidence of amyloid was less in patients who were dialysed for six years with high-flux synthetic membranes (one study, RR 0.03, 95% CI 0.00 to 0.54). There was a significant difference in favour of the synthetic (high-flux) membrane in comparison to cellulose membranes for triglycerides (WMD -0.66; 95% CI -1.18 to -0.14) but not for modified cellulose membranes. Dialysis adequacy measured by Kt/V was marginally higher when cellulose membranes were used (WMD -0.10; 95% CI -0.16 to 0.04), whereas synthetic membranes achieved significantly higher Kt/V values when compared with modified cellulose membranes (WMD 0.20, 95% 0.11 to 0.29) . There were no data on quality of life measures. AUTHORS' CONCLUSIONS: We found no evidence of benefit when synthetic membranes were compared with cellulose/modified cellulose membranes in terms of reduced mortality no reduction in dialysis-related adverse symptoms. Despite the relatively large number of RCTs undertaken in this area none of the included studies reported any measures of quality of life.

Cellulose↗

PubMed2005

Recombinant human erythropoietin for chronic renal failure anaemia in pre-dialysis patients.

BACKGROUND: Treatment with recombinant human erythropoietin (rHu EPO) in dialysis patients has been shown to be highly effective in terms of correcting anaemia and improving quality of life. There is debate concerning the benefits of rHu EPO use in pre-dialysis patients which may accelerate the deterioration of renal function. However the opposing view is that if rHu EPO is as effective in pre-dialysis patient's, improving the patients sense of well-being may result in the onset of dialysis being delayed. OBJECTIVES: To assess the effects of rHu EPO use in pre-dialysis patients with renal anaemia. SEARCH STRATEGY: The initial search included 13 electronic databases (1980 to May 2001) an internet search (August 1997), handsearching of Kidney International (1983 to May 1997), contact with known investigators and biomedical companies, and reference list of relevant articles. For this update we searched the Cochrane Renal Group's specialised register (June 2004) and The Cochrane Library (Issue 3, 2004). SELECTION CRITERIA: Randomised controlled trials (RCTs) or quasi-RCTs comparing the use of rHu EPO with no treatment or placebo in pre-dialysis patients. DATA COLLECTION AND ANALYSIS: Only published data were used. Quality assessment was performed by two assessors independently. Data were abstracted by a single author onto a standard form, a sample of which was checked by another author. Results were expressed as relative risk (RR) or weighted mean difference (WMD) with 95% confidence intervals (CI). MAIN RESULTS: Fifteen trials (461 participants) were included. There was a marked improvement in haemoglobin (WMD 1.82 g/dL, 95% CI 1.35 to 2.28) and haematocrit (WMD 9.85%, 95% CI 8.35 to 11.34) with treatment and a decrease in the number of patients requiring blood transfusions (RR 0.32, 95% CI 0.12 to 0.83). The data from studies reporting quality of life or exercise capacity demonstrated an improvement in the treatment group. Most of the measures of progression of renal disease showed no statistically significant difference. No significant increase in adverse events was identified. AUTHORS' CONCLUSIONS: Treatment with rHu EPO in pre-dialysis patients corrects anaemia, avoids the requirement for blood transfusions and also improves quality of life and exercise capacity. We were unable to assess the effects of rHu EPO on progression of renal disease, delay in the onset of dialysis or adverse events. Based on the current evidence, decisions on the putative benefits in terms of quality of life are worth the extra costs of pre-dialysis rHu EPO need careful evaluation.

Anemia↗

PubMed2005

Frequency of administration of recombinant human erythropoietin for anaemia of end-stage renal disease in dialysis patients.

BACKGROUND: The benefits of recombinant human erythropoietin (rHuEPO) administration in dialysis patients have been demonstrated, however the optimal frequency regimen have yet to be established. OBJECTIVES: To assess the effects of different frequency regimens of rHuEPO administration in dialysis patients on anaemia correction, quality of life and optimal use. SEARCH STRATEGY: We searched 13 electronic databases (1980 to May 2001) the internet (August 1997), handsearched Kidney International (1983 to May 1997), contacted known investigators, biomedical companies, and screened reference lists of relevant articles. Most recent search: The Cochrane Renal Group's specialised register (June 2004) and The Cochrane Library (Issue 3, 2004). SELECTION CRITERIA: Randomised controlled trials (RCTs) or quasi-RCTs comparing different frequencies of rHuEPO administration in dialysis patients. We compared haemodialysis and CAPD patients and subcutaneous and intravenous administration. DATA COLLECTION AND ANALYSIS: Quality assessment was performed by two assessors. Data were abstracted by a single author onto a standard form, and a sample was checked by another author. Results were expressed as relative risk (RR) or weighted mean difference (WMD) with 95% confidence intervals (CI). MAIN RESULTS: Eleven studies (719 patients) were included. There was no significant difference in maintaining target haemoglobin for once versus twice weekly administration (one study, 20 patients: RR 1.00, 95% CI 0.42 to 2.40) or mean haemoglobin after 12 weeks of therapy between haemodialysis and CAPD patients (two studies: WMD -0.21 g/dL, 95% CI -0.98 to 0.56) At the end of study for once versus thrice weekly administration (three studies: SMD -0.31, 95% CI -0.67 to 0.06) and at the end of maintenance phase (one study: WMD -0.2 g/dL, 95% CI -0.65 to 0.25) there was no significant difference. More rHuEPO was required by haemodialysis patients receiving once weekly versus twice weekly doses (WMD 12.0 U/kg, 95% CI 0.24 to 23.76). No difference was found for CAPD patients alone or combined (WMD 4.38 U/kg, 95% CI -11.28 to 20.04). Once versus thrice weekly administration was not significant (WMD 10.00 U/kg, 95% CI -80.87 to 100.87). There was no difference in the frequency of adverse events. AUTHORS' CONCLUSIONS: There is no significant difference between once weekly versus thrice weekly subcutaneous administration of rHuEPO. Once weekly administration would require an additional 12 U/kg/wk for patients on haemodialysis, however this is based on one very small study. Cost of additional rHuEPO needs to assessed with regard to patient preference and compliance.

Anemia↗

PubMed2005

Evidence for B0 s-->phiphi decay and measurements of branching ratio and A(CP) for B+ -->phiK+.

We present the first evidence of charmless decays of the B(0)(s) meson, the decay B(0)(s)--> phiphi, and a measurement of the branching ratio BR(B(0)(s)--> phiphi) using 180 pb(-1) of data collected by the CDF II experiment at the Fermilab Tevatron collider. In addition, the BR and direct CP asymmetry for the B+-->phiK+ decay are measured. We obtain BR(B(0)(s)--> phiphi)=[14(+6)(-5)(stat)+/-6(syst)] x 10(-6), BR(B+-->phiK+)=[7.6+/-1.3(stat)+/-0.6(syst)] x 10(-6), and A(CP)(B+-->phiK+)= -0.07+/-0.17(stat)+0.03 / -0.02(syst). Both decays are governed in the standard model by second order (penguin) b-->s(-)ss amplitudes.

Journal Article↗

PubMed2005

Measurement of the cross section for prompt diphoton production in pp collisions at square root of s=1.96 TeV.

We report a measurement of the rate of prompt diphoton production in pp collisions at square root of s=1.96 TeV using a data sample of 207 pb(-1) collected with the upgraded Collider Detector at Fermilab. The background from nonprompt sources is determined using a statistical method based on differences in the electromagnetic showers. The cross section is measured as a function of the diphoton mass, the transverse momentum of the diphoton system, and the azimuthal angle between the two photons and is found to be consistent with perturbative QCD predictions.

Journal Article↗

PubMed2005

Search for anomalous kinematics in tt dilepton events at CDF II.

We report on a search for anomalous kinematics of tt dilepton events in pp collisions at square root of s=1.96 TeV using 193 pb(-1) of data collected with the CDF II detector. We developed a new a priori technique designed to isolate the subset in a data sample revealing the largest deviation from standard model (SM) expectations and to quantify the significance of this departure. In the four-variable space considered, no particular subset shows a significant discrepancy, and we find that the probability of obtaining a data sample less consistent with the SM than what is observed is 1.0%-4.5%.

Journal Article↗

PubMed2005

Measurement of the W(+)W(-) production cross section in pp collisions at square root[s]=1.96 TeV using dilepton events.

We present a measurement of the W(+)W(-) production cross section using 184 pb(-1) of p(p) collisions at a center-of-mass energy of 1.96 TeV collected with the Collider Detector at Fermilab. Using the dilepton decay channel W(+)W(-)-->l(+)nul(-), where the charged leptons can be either electrons or muons, we find 17 candidate events compared to an expected background of 5.0(+2.2)(-0.8) events. The resulting W(+)W(-) production cross-section measurement of sigma(pp-->W(+)W(-))=14.6(+5.8)(-5.1)(stat)(+1.8)(-3.0)(syst) +/- 0.9(lum) pb agrees well with the standard model expectation.

Journal Article↗

PubMed2005

Measurement of charged-particle multiplicities in gluon and quark jets in pp collisions at square root of s = 1.8 TeV.

We report the first largely model independent measurement of charged particle multiplicities in quark and gluon jets, Nq and Ng, produced at the Fermilab Tevatron in pp collisions with a center-of-mass energy of 1.8 TeV and recorded by the Collider Detector at Fermilab. The measurements are made for jets with average energies of 41 and 53 GeV by counting charged particle tracks in cones with opening angles of theta(c) = 0.28, 0.36, and 0.47 rad around the jet axis. The corresponding jet hardness Q = Ejet theta c varies in the range from 12 to 25 GeV. At Q = 19.2 GeV, the ratio of multiplicities r = Ng/Nq is found to be 1.64+/-0.17, where statistical and systematic uncertainties are added in quadrature. The results are in agreement with resummed perturbative QCD calculations.

Journal Article↗

PubMed2005

Evaluation of cell-mediated immune responses and bacterial clearance in 6-10 months old water buffalo (Bubalus bubalis) experimentally vaccinated with four dosages of commercial Brucella abortus strain RB51 vaccine.

Thirty water buffalo, obtained from a brucellosis-free farm, were used to evaluate cell-mediated immune responses and bacterial clearance in response to vaccination with Brucella abortus strain RB51 (RB51) in a dose-response study. The animals were randomly divided into five treatment groups. Groups I--V received the recommended dose (RD) of RB51 vaccine once, RD twice 4 weeks apart, double RD once, double RD twice 4 weeks apart and saline once, respectively. Cell-mediated immune response to RB51 was assessed by the histological examination of haematoxylin and eosin (H&E) stained sections of lymph nodes draining the sites of inoculation and by comparison of stimulation indices (SI) derived from gamma interferon (IFN-gamma) assay. A mixture of cytoplasmic proteins from B. melitensis B115 (brucellergene) was used as a specific antigenic stimulus to peripheral blood mononuclear cells (PBMC) and lymph node mononuclear cells (LNMC) up to 22 post-initial-inoculation week (PIW). Supernatants harvested at 18-24h after the in vitro antigenic stimulus were assayed for their IFN-gamma content by using a commercial sandwich enzyme-linked immunosorbent assay (ELISA) kit. Clearance of RB51 was assessed by the sequential immunohistochemical examination of sections of draining lymph nodes post-inoculation. There was no observable expansion of the deep cortex of lymph nodes on H&E sections indicating poor T-cell stimulation. All group V (control) water buffalo PBMC ELISA values were negative (SI<2.2) at all PIW sampling intervals. Overall PBMC IFN-gamma assay detected vaccinates from treatment groups' I--IV 67% (4/6), 83% (5/6), 33% (2/6) and 67% (4/6), respectively. LNMC IFN-gamma assay was unimpressive and there was a negative correlation (--.08) between the results of PBMC and LNMC of IFN-gamma assay. Clearance of RB51 occurred between 4 and 6 PIW in treatment groups I and III and between 6 and 12 PIW in groups II and IV. RB51 was not detected in any of the control animals at sampling intervals post-inoculation.

Animals↗

PubMed2005

Measurement of partial widths and search for direct CP violation in D0 meson decays to K-K+ and pi-pi+.

We present a measurement of relative partial widths and decay rate CP asymmetries in K-K+ and pi(-)pi(+) decays of D0 mesons produced in pp collisions at sqrt[s]=1.96 TeV. We use a sample of 2x10(5) D(*+)-->D0pi(+) (and charge conjugate) decays with the D0 decaying to K-pi(+), K-K+, and pi(-)pi(+), corresponding to 123 pb(-1) of data collected by the Collider Detector at Fermilab II experiment at the Fermilab Tevatron collider. No significant direct CP violation is observed. We measure Gamma(D0-->K-K+)/Gamma(D0-->K-pi(+))=0.0992+/-0.0011+/-0.0012, Gamma(D0-->pi(-)pi(+))/Gamma(D0-->K-pi(+))=0.035 94+/-0.000 54+/-0.000 40, A(CP)(K-K+)=(2.0+/-1.2+/-0.6)%, and A(CP)(pi(-)pi(+))=(1.0+/-1.3+/-0.6)%, where, in all cases, the first uncertainty is statistical and the second is systematic.

Journal Article↗

PubMed2005

Search for excited and exotic electrons in the egamma decay channel in pp collisions at sqrt[s] = 1.96 TeV.

We present a search for excited and exotic electrons (e(*)) decaying to an electron and a photon, both with high transverse momentum. We use 202 pb(-1) of data collected in pp collisions at sqrt[s] = 1.96 TeV with the Collider Detector at Fermilab II detector. No signal above standard model expectation is seen for associated ee(*) production. We discuss the e(*) sensitivity in the parameter space of the excited electron mass M(e(*)) and the compositeness energy scale Lambda. In the contact interaction model, we exclude 132 GeV/c(2)<M(e(*))<879 GeV/c(2) for Lambda = M(e(*)) at 95% confidence level (C.L.). In the gauge-mediated model, we exclude 126 GeV/c(2) < M(e(*)) < 430 GeV/c(2) at 95% C.L. for the phenomenological coupling f/Lambda approximately 10(-2) GeV-1.

Journal Article↗

PubMed2005

Measurement of the lifetime difference between Bs mass eigenstates.

We present measurements of the lifetimes and polarization amplitudes for B(0)(s)-->J/psiphi and B(0)(d)-->J/psiK(*0) decays. Lifetimes of the heavy and light mass eigenstates in the B(0)(s) system are separately measured for the first time by determining the relative contributions of amplitudes with definite CP as a function of the decay time. Using 203+/-15 B(0)(s) decays we obtain tau(L) = (1.05(+0.16)(-0.13) +/- 0.02) ps and tau(H) = (2.07(+0.58)(-0.46) +/- 0.03) ps. Expressed in terms of the difference DeltaGamma(s) and average Gamma(s), of the decay rates of the two eigenstates, the results are DeltaGamma(s)/Gamma(s) = (65(+25)(-33) +/- 1)% and DeltaGamma(s) = (0.47(+0.19)(-0.24) +/- 0.01) ps(-1).

Journal Article↗

PubMed2005

First measurements of inclusive W and Z cross sections from run II of the fermilab tevatron collider.

We report the first measurements of inclusive W and Z cross sections times leptonic branching ratios for pp collisions at square root[s]=1.96 TeV, based on their decays to electrons and muons. The data correspond to an integrated luminosity of 72 pb(-1) recorded with the CDF detector at the Fermilab Tevatron. We test e-mu universality in W decays, and we measure the ratio of leptonic W and Z rates from which the leptonic branching fraction B(W-->lnu) can be extracted as well as an indirect value for the total width of the W and the Cabibbo-Kobayashi-Maskawa matrix element, |V(cs)|.

Journal Article↗

PubMed2005

Phase I study of TNFalpha AutoVaccIne in patients with metastatic cancer.

We evaluated the safety and immunogencity of a novel vaccine directed against autologous TNFalpha in a Phase I fixed dose escalation trial. The vaccine consisted of two recombinant TNFalpha proteins, with specific peptides replaced by foreign immunodominant T cell epitopes from tetanus toxoid. The main objectives were to establish a safe dose and evaluate the vaccines ability to raise neutralising TNFalpha antibodies. Secondary objectives were improvements in body weight and tumour response. Thirty-three patients were vaccinated with three doses (20, 100, or 400 mug) of TNFalpha vaccine at 2-weekly intervals adjuvanted with aluminium hydroxide. Anti-TNFalpha antibody titres were measured by both a RIA, using soluble native TNFalpha as the antigen, and by an ELISA using immobilized partly denatured TNFalpha. Eleven patients (33%) had mild grade1/2 injection site reactions at the higher doses. In 10 of 20 patients, serum antibodies recognize denatured TNFalpha in the ELISA, whereas, antibody titres against native TNFalpha in the RIA were undetectable. This suggests that the production process had partly denatured the vaccine preventing the formation of cross-reacting antibodies to native TNFalpha. In conclusion, TNFalpha vaccine was able to elicit vaccine specific antibodies. However, since the antibodies were only able to cross-react with partly denatured TNFalpha, evaluation of safety and tumour responses to the TNFalpha vaccine was compromised.

Aged↗

PubMed2005

Measurement of Wgamma and Zgamma production in pp collisions at square root s=1.96 TeV.

The standard model predictions for Wgamma and Zgamma production are tested using an integrated luminosity of 200 pb(-1) of pp collision data collected at the Collider Detector at Fermilab. The cross sections are measured by selecting leptonic decays of the W and Z bosons, and photons with transverse energy ET>7 GeV that are well separated from leptons. The production cross sections and kinematic distributions for the Wgamma and Zgamma data are compared to SM predictions.

Journal Article↗