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R Ward

Publications and source records attributed to R Ward.

At least 91 records · Page 5Linked to original sources
PubMed1999

Between-observer repeatability of sputum differential cell counts. Influence of cell viability and squamous cell contamination.

BACKGROUND: Induced sputum differential cell counts have been advocated as a method of noninvasively assessing airway inflammation in asthma and other airway diseases. Relatively little is known about the between-observer repeatability of sputum differential cell counts and the factors that influence it. OBJECTIVE: To assess the between-observer variability of induced sputum cell counts. METHODS: Sputum was induced and processed using standard techniques. Forty-two slides from 38 patients (31 with asthma, seven normal subjects) were randomly selected. Slides were classified as good (<20% squamous cells and >50% viability; n = 24); low viability (<50% viability; n = 10) and high squamous cell contamination (>20% squamous cells; n = 8). Two blinded observers counted between 200 and 400 nonsquamous cells and agreement was assessed by the intraclass correlation coefficient (ICC) and the standard deviation of between-observer differences (SD). RESULTS: The overall ICC were 0.9, 0.89, 0.9 for eosinophils, neutrophils and macrophages and 0.29 and 0.69 for lymphocytes and epithelial cells. Repeatability was greater in slides classified as good compared with slides with low cell viability and particularly excess squamous cell contamination. CONCLUSIONS: We have shown that the overall between-observer repeatability of the differential eosinophil, neutrophil and macrophage cell counts is good. Low cell viability and particularly excess squamous cell contamination reduce between-observer repeatability suggesting that techniques that ensure high cell viability and reduce squamous contamination would be an advantage.

Asthma↗
PubMed1999

Evidence of a major gene effect for angiotensinogen among Nigerians.

To dissect the genetic pathway of hypertension, we measured angiotensinogen in 685 members of 186 families recruited from a rural community in southwest Nigeria. Commingling and segregation analyses were carried out. A mixture of two and/or three distributions fits the data significantly better than a single distribution in commingling analysis, suggesting a major gene effect. Segregation analysis confirmed that a recessive major gene model for low values of angiotensinogen provides the best fit to the data and about 13% of the variance was due to the recessive gene segregation.

Adolescent↗
PubMed1999

Proteolytic fragments of Alzheimer's disease-associated presenilin 1 are present in synaptic organelles and growth cone membranes of rat brain.

Previous studies have demonstrated the molecular linkage of three causative genes for early-onset Alzheimer's disease: the presenilin 1 gene on chromosome 14, the presenilin 2 gene on chromosome 1, and the amyloid precursor protein gene on chromosome 21. In the present study, we have investigated the distributions of the approximately 20-kDa C-terminal and approximately 30-kDa N-terminal fragments of presenilin 1 and the amyloid precursor protein in rat brain and compared them with the distribution of several marker proteins. The fragments of presenilin 1 are present in synaptic plasma membranes, neurite growth cone membranes, and small synaptic vesicles of rat brain. Both proteolytic fragments are coenriched in the corresponding tissue fractions. Based on this observation, it seems likely that N- and C-terminal presenilin 1 fragments form a functional unit while remaining associated. In contrast to a predominant subcellular localization of presenilin 1 to the endoplasmic reticulum and Golgi apparatus in different cell lines, our results indicate that rat brain presenilin 1 fragments exit from these biosynthetic compartments to reach synaptic organelles in neurons.

Alzheimer Disease↗
PubMed1999

Maximum-likelihood generalized heritability estimate for blood pressure in Nigerian families.

Elevated blood pressure (BP) is more common in relatives of hypertensives than in relatives of normotensives, indicating familial resemblance of the BP phenotypes. Most published studies have been conducted in westernized societies. To assess the ability to generalize these estimates, we examined familial patterns of BP in a population-based sample of 510 nuclear families, including 1552 individuals (320 fathers, 370 mothers, 475 sons, and 387 daughters) from Ibadan, Nigeria. The prevalence of obesity in this community is low (body mass index: fathers, 21.6; mothers, 23.6; sons, 19.2; and daughters=21.0 kg/m2). The BP phenotype used in all analyses was created from the best regression model by standardizing the age-adjusted systolic blood pressure (SBP) and diastolic blood pressure (DBP) to 0 mean and unit variance. Heritability was estimated by use of the computer program SEGPATH from the most parsimonious model of "no spouse and neither gender nor generation difference" as 45% for SBP and 43% for DBP. The lack of a significant spouse correlation is consistent with little or no influence of the common familial environment. However, the heritability estimate of <50% for both SBP and DBPs reinforces the importance of the nonshared environmental effect.

Adult↗
PubMed1999

Eosinophilic bronchitis is an important cause of chronic cough.

Eosinophilic bronchitis presents with chronic cough and sputum eosinophilia, but without the abnormalities of airway function seen in asthma. It is important to know how commonly eosinophilic bronchitis causes cough, since in contrast to cough in patients without sputum eosinophilia, the cough responds to inhaled corticosteroids. We investigated patients referred over a 2-yr period with chronic cough, using a well-established protocol with the addition of induced sputum in selected cases. Eosinophilic bronchitis was diagnosed if patients had no symptoms suggesting variable airflow obstruction, and had normal spirometric values, normal peak expiratory flow variability, no airway hyperresponsiveness (provocative concentration of methacholine producing a 20% decrease in FEV(1) ([PC(20)] > 8 mg/ml), and sputum eosinophilia (> 3%). Ninety-one patients with chronic cough were identified among 856 referrals. The primary diagnosis was eosinophilic bronchitis in 12 patients, rhinitis in 20, asthma in 16, post-viral-infection status in 12, and gastroesophageal reflux in seven. In a further 18 patients a diagnosis was established. The cause of chronic cough remained unexplained in six patients. In all 12 patients with eosinophilic bronchitis, the cough improved after treatment with inhaled budesonide 400 micrograms twice daily, and in eight of these patients who had a follow-up sputum analysis, the eosinophil count decreased significantly, from 16.8% to 1.6%. We conclude that eosinophilic bronchitis is a common cause of chronic cough, and that sputum induction is important in the investigation of cough.

Administration, Inhalation↗
PubMed1999

Induced sputum eicosanoid concentrations in asthma.

Further definition of the role of leukotrienes (LT) and prostaglandins (PG) in asthma would be helped by a noninvasive method for assessing airway production. The supernatant from sputum induced with hypertonic saline and dispersed using dithiotrietol has been successfully used to measure other molecular markers of airway inflammation and might be a useful method. We have measured induced sputum supernatant LTC(4)/D(4)/E(4) concentrations using enzyme immunoassay and PGE(2), PGD(2), TXB(2), and PGF(2alpha) using gas chromatography-negative ion chemical ionization-mass spectroscopy in 10 normal subjects and in 26 subjects with asthma of variable severity. Sputum cysteinyl-leukotrienes concentrations were significantly greater in subjects with asthma (median, 9.5 ng/ml) than in normal control subjects (6.4 ng/ml; p < 0.02) and greater in subjects with persistent asthma requiring inhaled corticosteroids (median, 11.4 ng/ml) or studied within 48 h of an acute severe exacerbation of asthma (13 ng/ml) than in subjects with episodic asthma treated with inhaled beta(2)-agonists only (7.2 ng/ml). There were no significant differences in the concentrations of other eicosanoids between groups, although there was a negative correlation between the percentage sputum eosinophil count and sputum PGE(2) concentration (r = -0.48; p < 0.01) in subjects with asthma. We conclude that induced sputum contains high concentrations of eicosanoids and that sputum LTC(4)/D(4)/E(4) concentrations are significantly greater in subjects with asthma than in normal subjects. The inverse relationship between eosinophilic airway inflammation and sputum PGE(2) concentration would be consistent, with the latter having an anti-inflammatory role.

Adult↗
PubMed1999

Incidence and predictors of central venous catheter related infection in intensive care patients.

This study investigated the incidence of and risk factors for central venous catheter (CVC) infection in intensive care. CVCs were prospectively studied in patients who had lines inserted in general or neurosurgical intensive care and were expected to have the line in situ for at least 72 hours. Catheters (n = 119) were cultured for CVC-related infection (CRI; > 15 colony forming units) and blood cultures done when indicated. CRI was identified in 32 (26.9%) catheters, CVC related bacteraemia in five cases (4.2%) and CVC related sepsis in none. After adjustment for duration of catheterization, independent predictors of CVC related infection were catheter insertion site, with jugular sites having the highest risk, and primary diagnosis, with neurosurgical patients at least risk.

Adolescent↗
PubMed1999

How to defuse compliance time bombs. Part 2: Six hypothetical allegations. Panel discussion.

In the second and final part of this series, a panel of legal experts discusses more hypothetical allegations against a fictional laboratory, including billing for additional indices, using expired reagents, and falsifying the results of employee competency tests. Learn how to handle these dilemmas before they explode into full-blown legal violations.

Clinical Laboratory Techniques↗
PubMed1999

The impact of training in problem-based interviewing on the detection and management of psychological problems presenting in primary care.

BACKGROUND: The vast majority of mental health problems present to primary care teams. However, rates of under-diagnosis remain worryingly high. This study explores a GP-centred approach to these issues. AIM: To examine the impact of training in problem-based interviewing (BPI) on the detection and management of psychological problems in primary care. METHOD: The detection and management of psychological problems by 10 general practitioners (GPs) who had received PBI training 12 months earlier was compared with that of 10 control GPs matched for age, sex, clinical experience, and practice setting; and had originally applied for, but had not been able to attend, BPI training. Consecutive attendees at one randomly selected surgery undertaken by each GP were invited to participate in the study. Two hundred and eighty patients living in Newcastle upon Tyne met inclusion criteria and gave informed consent. The presence or absence of psychological problems was assessed using patient self-ratings on the 28-item version of the General Health Questionnaire (GHQ) and blind independent observer ratings of the brief Present State Examination (PSE). Patient satisfaction with interviews was rated using the Medical Interview Satisfaction Scale (MISS). After each consultation, the GPs (blind to subjective and observer ratings) recorded their assessment and management of the patients' problems on a Practice Activity Card (PAC). RESULTS: In comparison with control GPs, index GPs demonstrated significantly greater sensitivity in the detection of psychological problems in the GHQ-PAC ratings. The absolute decrease in misdiagnosis of GHQ cases was 9% and of PSE cases was 15%. Patients meeting GHQ criteria for caseness were more likely to be prescribed psychotropic medication by an index GP than compared with a control GP. Length of interview did not differ between the groups and mean scores on the MISS suggested that patients attending PBI-trained GPs, compared with control GPs, were as satisfied or slightly more satisfied with their consultation. CONCLUSION: In comparison with control GPs, PBI-trained GPs were better at recognizing and managing psychological disorders. The potential benefits of BPI training are discussed in light of other attempts to improve mental health skills in primary care.

Adult↗
PubMed1998

Cervical epidural steroid injection with intrinsic spinal cord damage. Two case reports.

STUDY DESIGN: Intrinsic cervical spinal cord damage represents the serious and permanent complications that can occur if cervical epidural steroid injections are administered while the patient is sedated. Two case reports are presented. OBJECTIVES: To draw attention to the dangerous consequences that can arise from sedating a patient before administering a cervical epidural steroid injection. SUMMARY OF BACKGROUND DATA: Reported complications of cervical epidural steroid injections have been minor and infrequent. No reports of intrinsic cervical cord damage could be found in a comprehensive English language literature search. METHODS: Two case reports of permanent intrinsic cervical cord damage in patients who had been administered cervical epidural steroid injections while under intravenous sedation are presented. Magnetic resonance imaging was performed before and after the administration of cervical epidural steroid injections. Each patient had herniated nucleus pulposus before they received cervical epidural steroid injections and intrinsic cord damage on postinjection magnetic resonance images. RESULTS: Both patients developed increased pain and neurologic symptoms within 24 hours of injection. To date, these symptoms appear to be permanent. However, Patient 1 had pain relief in her right arm and shoulder after undergoing a microdiscectomy, but pain was still persistent in her left leg, and she has developed a positive Lhermitte's sign. CONCLUSION: These case reports indicate fluoroscopic guidance will not insure or prevent intrathecal perforation or spinal cord penetration during the administration of cervical epidural steroid injections. In addition, although intravenous sedations during cervical epidural steroid injections have been used numerous times without reported complications, it appears intravenous sedation in these two cases resulted in the inability of the patient to experience the expected pain and paresthesias at the time of spinal cord irritation. Therefore, the authors conclude that the patient should be fully awake during the administration of cervical epidural steroid injections, with only local anesthetic in the skin used for analgesia.

Adult↗
PubMed1998

Retinal and cortical afferents to the dorsal lateral geniculate nucleus of the turtle, Emys orbicularis: a combined axonal tracing, glutamate, and GABA immunocytochemical electron microscopic study.

The dorsal lateral geniculate nucleus (GLd) of the turtle Emys orbicularis has been analyzed with axonal tracing methods and immunocytochemical techniques for glutamate (GLU) and gamma-aminobutyric acid (GABA), in combination with a quantitative study of the morphologic characteristics, distribution, and synaptology of the retinofugal and corticofugal terminals. Ultrastructural observations show that the vast majority of retinal terminals (Rtr) have clear, rounded synaptic vesicles and account for 16% of all profiles containing synaptic vesicles (PCSV). Their synaptic index (0.5) is low, and they make three times more contacts with the dendrites of projection cells than with those of interneurons. A low proportion of retinal terminals of a second category contain pleomorphic synaptic vesicles and are highly GABA immunoreactive. Axon terminals, unlabeled after intraocular injection of the tracer (SR), smaller in size and with more rounded clear synaptic vesicles, longer synaptic differentiations, and higher synaptic index than Rtr terminals, account for 19.7% of all PCSV and make asymmetric synaptic contacts with large dendrites of projection cells and less with the dendrites of interneurons. Some SR have been unambiguously identified as corticofugal terminals (Cg), either after cortical injection of the tracer (16%) or cortical lesion (37%). Retinal and Cg/SR terminals are spatially segregated within the GLd. Both are highly GLU immunoreactive, with the highest density of labeling over synaptic vesicles, suggesting that these terminals may use GLU as neurotransmitter. The level of GLU immunoreactivity of GABA-positive profiles is half that of Rtr and Cg/SR terminals and is greatest over mitochondria, possibly reflecting the 'metabolic' pool of GLU that serves as a precursor in the formation of GABA.

Afferent Pathways↗
PubMed1998

Restriction endonuclease-mediated selective polymerase chain reaction: a novel assay for the detection of K-ras mutations in clinical samples.

The enriched polymerase chain reaction (PCR) assay has been used extensively in the detection of ras gene mutations in many types of human malignancies. Although it is very sensitive, it has a number of features that limit its use in the routine diagnostic laboratory. The aim of this study was to develop a novel enriched PCR strategy, in which the concurrent activity of the restriction enzyme BstNI and Taq polymerase allowed the amplification of mutant K-ras while inhibiting the formation of wild-type product. This restriction endonuclease-mediated selective PCR assay uses three sets of primers, together with BstNI, in the reaction mix, and the amplification products are analyzed by gel electrophoresis. The reliability of the restriction endonuclease-mediated selective PCR assay to detect activated K-ras was determined in a variety of clinical samples, including 139 fresh colorectal carcinomas and 113 paraffin-embedded blocks from 80 separate tumors of the colon and rectum, pancreas, breast, or kidney. Codon 12 mutations of the K-ras oncogene were identified in DNA from both fresh and paraffin-embedded tumors in a rapid, sensitive, and reproducible manner. Mutations were detected in 33 (24%) of the fresh colorectal cancers and 16 (20%) of the paraffin-embedded tumors. These results were 97% concordant in cases in which paraffin blocks and fresh specimens from the same tumor were available for analysis. We conclude that restriction endonuclease-mediated selective PCR is a sensitive, rapid, and robust assay for the detection of point mutations in a variety of clinical samples. Importantly, there is no need for manipulation of the sample once the PCR has been set up, and therefore, the chance of contamination is significantly reduced. In contrast to previous assays, restriction endonuclease-mediated selective PCR is not labor intensive, and its format is suitable for use in routine diagnostic laboratory.

Adenocarcinoma↗