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Biomedical subjects

J Booth

Publications and source records attributed to J Booth.

At least 19 recordsLinked to original sources
PubMed2006

Immunomodulatory effects of Toll-like receptor-7 activation on chronic lymphocytic leukemia cells.

Weak immunogenicity of chronic lymphocytic leukemia (CLL) cells may contribute to disease progression and inhibit effective immunotherapy. Accordingly, agents that enhance the immunogenicity of CLL cells may be useful in immunotherapeutic approaches to this disease. Since Toll-like receptors (TLRs) are major regulators of innate immunity and initiation of adaptive immunity, we studied the effects of viral pathogen associated molecular pattern agonists (that are recognized by TLRs) on the costimulatory phenotype and function of CLL cells. CLL cells (especially those with high endogenous expression of CD38) responded to TLR7-activating imidazoquinolines and guanosine analogs by increasing costimulatory molecule expression, producing inflammatory cytokines, and becoming more sensitive to killing by cytotoxic effectors. Additional activation of protein kinase C pathways increased the ability to stimulate T-cell proliferation, blocked phosphorylation of the transcription factor, signal transducer and activator of transcription (STAT)3, and resulted in the acquisition of a dendritic cell surface phenotype by TLR7-activated CLL cells. Normal B cells also responded to TLR7 activation by increasing costimulatory molecule expression and cytokine production. These findings suggest a potential role for TLR7 agonists in CLL immunotherapy.

Adult↗
PubMed2005

The SV stent study: a prospective, multicentre, angiographic evaluation of the BiodivYsio phosphorylcholine coated small vessel stent in small coronary vessels.

OBJECTIVE: To evaluate the use of the phosphorylcholine (PC) coated BiodivYsio small vessel (SV) stent in native coronary vessels of small calibre. DESIGN AND SETTING: Prospective, multi-centre, multi-national registry with 6-month clinical and core-lab angiographic follow-up. Adverse events were adjudicated by a Clinical Events Committee (CEC) and included peri-procedural analysis of cardiac enzymes. PATIENTS: Patients with signs or symptoms of ischaemia with an identified target lesion in an epicardial vessel with reference diameter 2.0-2.75 mm were enrolled. Intervention in other epicardial territories in the same patient was permitted. RESULTS: Recruitment of 150 consecutive lesions (in 143 patients) was completed in 19 centres in Europe and Israel. The stent was deployed successfully in all but one lesion. At 6 months, 1 patient (1%) had experienced sudden cardiac death, 4 further patients (3%) had a non-Q wave MI, and a further 24 patients (17%) had repeat revascularisation of a study target vessel. The mean reference vessel diameter prior to stenting was 2.2 mm (S.D. 0.4). Mean minimal luminal diameters at pre-procedure, post procedure and follow-up were 0.6 mm (S.D. 0.3), 2.0 mm (S.D. 0.4) and 1.2 mm (S.D. 0.6), respectively. The late lumen loss index was 0.55 (S.D. 0.53) with a binary restenosis rate of 32%. CONCLUSIONS: In stenting of selected lesions in small vessels, the BiodivYsio SV stent demonstrated high rates of implant success. The rates of major adverse cardiac events (MACE), angiographic restenosis and repeat revascularisation are similar to those reported in other small vessel bare metal stent studies.

Adult↗
PubMed2004

Determining the critical relative humidity for moisture-induced phase transitions.

A new method to determine the onset relative humidity for a glass transition and crystallization processes in amorphous or partially amorphous materials was developed using dynamic gravimetric vapor sorption (DVS). Water vapor can act as a plasticizing agent in amorphous materials, thus lowering the glass transition temperature below room temperatures. Additional water sorption can lead to a crystallization event below the glass transition temperature. On spray-dried lactose the glass transition RH and crystallization RH values were 30 and 58% at 25 degrees C, respectively. Glass transition and crystallization RH values were also measured at 5, 15, 25, 35, and 45 degrees C on a spray-dried salbutamol sulfate sample. The glass transition RH values for the salbutamol sulfate sample ranged from 64.5% RH (5 degrees C) to 32.8% RH (45 degrees C) while the crystallization RH values ranged from 81.0% RH (5 degrees C) to 50.4% RH (45 degrees C). The results clearly show that the glass transition and crystallization humidity values decrease as the sample temperature increases.

Albuterol↗
PubMed2004

A randomised controlled trial to compare a nurse practitioner to medical staff in the preparation of patients for diagnostic cardiac catheterisation: the study of nursing intervention in practice (SNIP).

BACKGROUND: A number of initiatives have employed nurses in roles traditionally associated with the medical profession but few have been evaluated in prospective randomised studies. This paper reports the results of a randomised controlled trial to assess the performance of a nurse practitioner (NP), trained to prepare patients for diagnostic cardiac catheterisation. METHODS: Eligible and consenting patients were randomised to preparation by either the NP or junior medical staff (JMS). The safety outcome measure was the rate of in-hospital major adverse clinical events including death, myocardial infarction and emergency bypass coronary surgery. Other outcome measures included rate of minor adverse events, cardiologist assessment of case preparation and presentation, patient satisfaction and duration of pre-admission clinic. RESULTS: From April 1997 to May 1998 a series of 355 patients scheduled for elective, day-case, diagnostic cardiac catheterisation were screened. Of these, 345 patients were eligible for the study. A total of 339 patients consented to participate and were randomised. Major adverse clinical events occurred in 0/175 (0%) patients in the NP group and 2/161 (1.2%) patients in the JMS group. (Risk difference = -1.2%, upper boundary of the 95% confidence interval = +2.0%) The cardiologist's evaluation that the patient's preparation was acceptable was high in both groups: NP group 98.3% vs. JMS group 98.8%: P = 1.0). Patient satisfaction, assessed by questionnaire, was greater in the NP group (P = 0.04). The median duration of the pre-admission clinic visit was lower in the NP group 165 min vs. 185 min in the JMS group, P = 0.01). CONCLUSIONS: The preparation of patients for diagnostic cardiac catheterisation can be safely performed by an appropriately trained NP. This approach may be associated with improved patient satisfaction and reduced clinic duration times.

Cardiac Catheterization↗
PubMed2004

One year comparison of costs of coronary surgery versus percutaneous coronary intervention in the stent or surgery trial.

OBJECTIVES: To compare initial and one year costs of coronary artery bypass grafting (CABG) versus percutaneous coronary intervention (PCI) in the stent or surgery trial. DESIGN: Prospective, unblinded, randomised trial. SETTING: Multicentre study. PATIENTS: 988 patients with multivessel disease. INTERVENTIONS: CABG and stent assisted PCI. MAIN OUTCOME MEASURES: Initial hospitalisation and one year follow up costs. RESULTS: At one year mortality was 2.5% in the PCI arm and 0.8% in the CABG arm (p = 0.05). There was no difference in the composite of death or Q wave myocardial infarction (6.9% for PCI v 8.1% for CABG, p = 0.49). There were more repeat revascularisations with PCI (17.2% v 4.2% for CABG). There was no significant difference in utility between arms at six months or at one year. Quality adjusted life years were similar 0.6938 for PCI v 0.6954 for PCI, Delta = 0.00154, 95% confidence interval (CI) -0.0242 to 0.0273). Initial length of stay was longer with CABG (12.2 v 5.4 days with PCI, p < 0.0001) and initial hospitalisation costs were higher (7321 pounds sterling v 3884 pounds sterling for PCI, Delta = 3437 pounds sterling, 95% CI 3040 pounds sterling to 3848 pounds sterling). At one year the cost difference narrowed but costs remained higher for CABG (8905 pounds sterling v 6296 pounds sterling for PCI, Delta = 2609 pounds sterling, 95% CI 1769 pounds sterling to 3314 pounds sterling). CONCLUSIONS: Over one year, CABG was more expensive and offered greater survival than PCI but little added benefit in terms of quality adjusted life years. The additional cost of CABG can be justified only if it offers continuing benefit at no further increase in cost relative to PCI over several years.

Angioplasty, Balloon, Coronary↗
PubMed2004

The utility of the AC/TC ratio for watershed management: a case study.

A human-impacted watershed was monitored during the dry summer seasons in 2002 and 2003 to investigate the impact of providing access to sewer mains to local village residences. Faecal coliform concentrations were monitored at select sites along the 30-mile stretch of creek, together with faecal streptococci, enterococci and total coliforms. Analysis of the results found that levels of faecal coliforms were inadequate at identifying significant known influxes of human and animal sewage established by sanitary survey. However, the bacterial ratio of atypical colonies to total coliform colonies (AC/TC), obtained from the total coliform membrane filter assay on m-Endo media, correctly indexed human faecal impact of inadequately sewered villages located along the creek. In addition, the AC/TC ratio correctly classified the predominant source of faecal runoff in the creek headwaters as agricultural, and indicated when aged agricultural faecal material was introduced by tributaries. An approach for watershed management that uses the AC/TC ratio in addition to levels of bacteria is proposed.

Enterobacteriaceae↗
PubMed2003

Risk of intracranial haemorrhage with combined fibrinolytic and glycoprotein IIb/IIIa inhibitor therapy in acute myocardial infarction. Dichotomous response as a function of age in the GUSTO V trial.

BACKGROUND: Intracranial haemorrhage is an important limitation to pharmacologic reperfusion therapy for acute myocardial infarction. The combination of a glycoprotein IIb/IIIa inhibitor, half-dose plasminogen activator and reduced-dose heparin has been evaluated as an alternative to standard fibrinolytic therapy in this setting. METHODS AND RESULTS: We evaluated the relation between univariate and multivariate predictors of intracranial haemorrhage and the effect of treatment with either reteplase alone (10 U bolus twice, 30 min apart) with standard-dose heparin (5000 U bolus followed by an infusion of 1000 Uh(-1)for patients > or =80 kg and 800 Uh(-1)for those <80 kg) or combination therapy with abciximab (0.25mg/kg bolus and 0.125 microg/kg/min for 12h) and half-dose reteplase (two boluses of 5U 30 min apart) with reduced-dose heparin (60 Ukg(-1)bolus, maximum 5000 U, followed by an infusion of 7 Ukg(-1)h(-1)) in the 16 588 patients randomized in the GUSTO V trial. Overall, the incidence of intracranial haemorrhage was similar in the two groups (0.6% vs 0.6%; OR 1.05, 95% CI 0.71, 1.56). The median (25th-75th) time from drug administration to intracranial haemorrhage was 5.5 (3.4-11) hours with combination therapy and 9.2 (5.9-22) hours with reteplase (P=0.048). Among the multivariable predictors of intracranial haemorrhage, only age showed a significant interaction with treatment effect (age per treatment interaction chi-square 4.60, P=0.032) with a lower risk of combination therapy for younger patients and a higher risk for the elderly. CONCLUSIONS: Although no additional risk of intracranial haemorrhage has been observed with combination therapy in the whole population, a significant age pertreatment interaction exists, with a lower risk with combination therapy in younger patients, and a higher risk in the elderly.

Abciximab↗
PubMed2001

Observation of high-energy neutrinos using Cerenkov detectors embedded deep in Antarctic ice.

Neutrinos are elementary particles that carry no electric charge and have little mass. As they interact only weakly with other particles, they can penetrate enormous amounts of matter, and therefore have the potential to directly convey astrophysical information from the edge of the Universe and from deep inside the most cataclysmic high-energy regions. The neutrino's great penetrating power, however, also makes this particle difficult to detect. Underground detectors have observed low-energy neutrinos from the Sun and a nearby supernova, as well as neutrinos generated in the Earth's atmosphere. But the very low fluxes of high-energy neutrinos from cosmic sources can be observed only by much larger, expandable detectors in, for example, deep water or ice. Here we report the detection of upwardly propagating atmospheric neutrinos by the ice-based Antarctic muon and neutrino detector array (AMANDA). These results establish a technology with which to build a kilometre-scale neutrino observatory necessary for astrophysical observations.

Journal Article↗
PubMed2001

Whole-body pre-cooling does not alter human muscle metabolism during sub-maximal exercise in the heat.

Muscle metabolism was investigated in seven men during two 35 min cycling trials at 60% peak oxygen uptake, at 35 degrees C and 50% relative humidity. On one occasion, exercise was preceded by whole-body cooling achieved by immersion in water during a reduction in temperature from 29 to 24 degrees C, and, for the other trial, by immersion in water at a thermoneutral temperature (control, 34.8 degrees C). Pre-cooling did not alter oxygen uptake during exercise (P > 0.05), whilst the change in cardiac frequency and body mass both tended to be lower following pre-cooling (0.05 < P < 0.10). When averaged over the exercise period, muscle and oesophageal temperatures after pre-cooling were reduced by 1.5 and 0.6 degrees C respectively, compared with control (P < 0.05). Pre-cooling had a limited effect on muscle metabolism, with no differences between the two conditions in muscle glycogen, triglyceride, adenosine triphosphate, creatine phosphate, creatine or lactate contents at rest, or following exercise. These data indicate that whole-body pre-cooling does not alter muscle metabolism during submaximal exercise in the heat. It is more likely that thermoregulatory and cardiovascular strain are reduced, through lower muscle and core temperatures.

Adult↗
PubMed2001

Observing washing and dressing of stroke patients: nursing intervention compared with occupational therapists. What is the difference?

This study sought to compare the interventions of qualified nurses with those of occupational therapists during morning care with the same population of stroke patients. Nonparticipant structured observation was used to identify the activities and interventions carried out by each of the two groups in a naturalistic care setting. Approval for the study was granted by the local ethics committee. In order to allow comparison between pairs, staff-patient interactions during morning care (n=10) were observed by a single researcher, firstly, with an occupational therapist and within 3 days of this, with a nurse. Twenty observation sessions were recorded in total during which time the activities, contacts and interactions were coded and recorded at 20-second intervals on a standard proforma. Analysis was undertaken using the Statistical Package for Social Sciences (SPSS) for windows. The results showed that occupational therapists used 'prompting and instructing' commands more than nurses and used facilitation techniques significantly more (P=0.0283). 'Supervision' interactions were preferred by nurses with 42.1% of their time spent performing this activity compared with 25.1% for occupational therapists. These results are limited to the group under observation. It is suggested that the reasons for the observed differences in intervention styles used by occupational therapists and nurses may be attributed to the approach taken to the assessment and treatment of stroke patients. This difference might be attributed to a lack of preparation for specialist neurological/neurovascular practices of nurses working in the field of stroke rehabilitation.

Activities of Daily Living↗
PubMed2001

Family interventions after traumatic brain injury: a service example.

Traumatic brain injury (TBI) often exerts a major impact upon the family with high levels of stress and distress, particularly amongst primary carers, disruption to family life style and functioning, changes in family roles, and marital and sexual difficulties. In response to the documented impact upon the family a range of family services have been advocated including family education, counselling and support. This paper outlines family services developed within a community head injury service in the UK. The family assessment programme comprises a relatives' screening questionnaire and structured interview schedules and ratings scales, some drawn from the family assessment literature, others developed within the service. Four components of family intervention are described: an annual series of educational workshops; follow-up workshops; individual family support; and specialist marital counselling. Our experience of providing these family services over the last 7 years is discussed along with the need for further evaluation of family assessment and interventions after TBI.

Brain Injuries↗
PubMed2000

Susceptibility locus for Alzheimer's disease on chromosome 10.

The apolipoprotein E (APOE) gene is the only genetic risk factor that has so far been linked to risk for late-onset Alzheimer's disease (LOAD). However, 50 percent of Alzheimer's disease cases do not carry an APOE4 allele, suggesting that other risk factors must exist. We performed a two-stage genome-wide screen in sibling pairs with LOAD to detect other susceptibility loci. Here we report evidence for an Alzheimer's disease locus on chromosome 10. Our stage one multipoint lod score (logarithm of the odds ratio for linkage/no linkage) of 2.48 (266 sibling pairs) increased to 3.83 in stage 2 (429 sibling pairs) close to D10S1225 (79 centimorgans). This locus modifies risk for Alzheimer's disease independent of APOE genotype.

Age of Onset↗
PubMed2000

Mode of action and application of Scorpion primers to mutation detection.

Scorpion primers can be used to detect PCR products in homogeneous solution. Their structure promotes a unimolecular probing mechanism. We compare their performance with that of the same probe sequence forced to act in a bimolecular manner. The data suggest that Scorpions indeed probe by a unimolecular mechanism which is faster and more efficient than the bimolecular mechanism. This mechanism is not dependent on enzymatic cleavage of the probe. A direct comparison between Scorpions, TaqMan and Molecular Beacons on a Roche LightCycler indicates that Scorpions perform better, particularly under fast cycling conditions. Development of a cystic fibrosis mutation detection assay shows that Scorpion primers are selective enough to detect single base mutations and give good sensitivity in all cases. Simultaneous detection of both normal and mutant alleles in a single reaction is possible by combining two Scorpions in a multiplex reaction. Such favourable properties of Scorpion primers should make the technology ideal in numerous applications.

Alleles↗
PubMed2000

Passive infusion of immune serum into simian immunodeficiency virus-infected rhesus macaques undergoing a rapid disease course has minimal effect on plasma viremia.

Antibody responses are often considered to play only a limited role in controlling viremia during chronic infections with human or simian immunodeficiency virus (SIV). We investigated this by determining the effect of passively infused antibody on plasma viremia in infected rhesus macaques. The emphasis of the study was to understand the mechanism(s) underlying any observed effects. We infused serum immunoglobulins (SIVIG) purified from SIV(mac)251-infected macaques into other SIV(mac)251-infected macaques. The rapid progressor recipients had high viral loads but negligible titers of antibodies to SIV. Thus, we could significantly increase antibody titers with exogenous SIVIG. Despite restoring anti-SIV titers to levels typical of macaques with a normal disease course, SIVIG had only a modest effect on plasma SIV RNA and cell-associated viral load; the maximum, transient, reduction was threefold. The decrease in plasma RNA commenced within 1-2 h of SIVIG infusion, the nadir was at 12 h, and then a rebound occurred. A two- to threefold drop in cell-associated viral RNA was simultaneous with the decrease in plasma RNA. The kinetics of the viremia changes are inconsistent with neutralization of new cycles of infection. More likely, perhaps unexpectedly, is that infused antibodies killed SIV-infected cells, via an effector mechanism such as antibody-dependent cellular cytotoxicity.

Animals↗
PubMed2000

Assessment of peripheral neuropathy in the diabetic foot.

Peripheral neuropathy is associated with major morbidity in the diabetic population. The detection of whether peripheral neuropathy is simply present or not in patients with diabetes is insufficient. What is required is a reliable measure of both the extent and severity of neuropathy, as this enables the appropriate allocation of resources and improves the quality of care for the patients who need it most. Standardized approaches involving the use of a neurothesiometer and a 10 g monofilament can provide a reliable and objective measure of the extent and severity of neuropathy, and should therefore be adopted into protocols for best practice in the assessment of neuropathy.

Diabetic Foot↗
PubMed2000

Skeletal muscle metabolic and ionic adaptations during intense exercise following sprint training in humans.

The effects of sprint training on muscle metabolism and ion regulation during intense exercise remain controversial. We employed a rigorous methodological approach, contrasting these responses during exercise to exhaustion and during identical work before and after training. Seven untrained men undertook 7 wk of sprint training. Subjects cycled to exhaustion at 130% pretraining peak oxygen uptake before (PreExh) and after training (PostExh), as well as performing another posttraining test identical to PreExh (PostMatch). Biopsies were taken at rest and immediately postexercise. After training in PostMatch, muscle and plasma lactate (Lac(-)) and H(+) concentrations, anaerobic ATP production rate, glycogen and ATP degradation, IMP accumulation, and peak plasma K(+) and norepinephrine concentrations were reduced (P<0.05). In PostExh, time to exhaustion was 21% greater than PreExh (P<0.001); however, muscle Lac(-) accumulation was unchanged; muscle H(+) concentration, ATP degradation, IMP accumulation, and anaerobic ATP production rate were reduced; and plasma Lac(-), norepinephrine, and H(+) concentrations were higher (P<0.05). Sprint training resulted in reduced anaerobic ATP generation during intense exercise, suggesting that aerobic metabolism was enhanced, which may allow increased time to fatigue.

Acid-Base Equilibrium↗
PubMed2000

Differences in the performance of commercially available 10-g monofilaments.

OBJECTIVE: This independent study was designed to determine the accuracy of 10-g monofilaments manufactured and supplied by popular commercial companies. RESEARCH DESIGN AND METHODS: A total of 160 new 10-g monofilaments (30 Semmes-Weinstein monofilaments [North Coast Medical], 30 Timesco/Sensory Testing Systems monofilaments, 50 Owen Mumford Neuropens, and 50 Bailey Instruments monofilaments) were tested using a calibrated load cell. Each monofilament was subjected to 10 mechanical bucklings of 10 mm while the load cell detected the maximum buckling force. Longevity testing was performed on a subset of the monofilaments by subjecting them to continuous compressions until the buckling force was <9 g. RESULTS: The accuracy of monofilaments to produce a buckling force of 10 g varies among manufacturers. Bailey Instruments and Owen Mumford filaments were the most accurate with 100% buckling within +/-1.0 g of 10 g. Only 70% of the Semmes-Weinstein monofilaments from North Coast Medical buckled within +/-1.0 g of 10 g. A total of 80% of Timesco filaments buckled at <8 g. Longevity tests on Bailey Instruments and Owen Mumford monofilaments demonstrated that 80% continued to buckle within 10% of 10 g after 100 compressions, but only 50% were within this range after 200 compressions. The maximum amount of recovery achieved in any monofilament occurred within 24 h. CONCLUSIONS: Monofilaments made by either Bailey Instruments or Owen Mumford are recommended for use in clinical practice. North Coast Medical monofilaments may operate differently in the U.S. because of different environmental conditions such as differences in humidity. Timesco/Sensory Testing Systems monofilaments were neither accurate enough nor Conformity European marked to recommend their use in the U.K. Longevity and recovery testing suggest that each monofilament will survive usage on approximately 10 patients before needing a recovery time of 24 h before further use.

Calibration↗