Search PubMed⌕ Search

Biomedical subjects

M Johnson

Publications and source records attributed to M Johnson.

At least 145 records · Page 8Linked to original sources
PubMed2000

Dissociating nicotine and nonnicotine components of cigarette smoking.

To dissociate the sensorimotor aspects of cigarette smoking from the pharmacologic effects of nicotine, smokers rated the subjective effects of nicotine-containing or denicotinized cigarettes, and intravenous (IV) nicotine or saline infusions. Three groups of participants (n=20 per group) received either: (1) continuous nicotine, (2) pulsed nicotine, or (3) saline. Each group was exposed to an IV condition once while smoking a denicotinized cigarette and once while not smoking, in a 3x2 mixed design. A fourth group (n=20) received saline while smoking their usual brand of cigarette. The dose and rate of nicotine administration were individualized based on previous measures of ad lib smoke intake. Denicotinized cigarette smoke significantly reduced craving and was rated significantly more satisfying and rewarding than the no-smoking conditions. IV nicotine reduced craving for cigarettes, and increased ratings of lightheadedness and dizziness. However, no significant satisfaction or reward was reported after IV nicotine. The combination of IV nicotine and denicotinized cigarette smoke produced effects similar to those of smoking the usual brand of cigarette. The results suggest that sensorimotor factors are critical in mediating the immediate subjective response to smoking, and that the immediate subjective effects of nicotine administered in doses obtained from cigarette smoking are subtle. Thus, addressing smokers' needs for both for the sensorimotor aspects of smoking as well as for the direct CNS effects of nicotine may be critical in enhancing smoking cessation treatment outcome.

Adolescent↗
PubMed2000

Ureteropelvic junction obstruction. Retrograde endopyelotomy.

The modern day treatment of UPJO with retrograde endopyelotomy continues to evolve as experience and knowledge progress. Use of the straight lateral incision and selective use of spiral CT angiogram has refined treatment decisions with retrograde endopyelotomy further. The authors' decision-oriented approach offers guidelines for the practicing urologist. Ultimately, it is up to the urologist and the patient to select the best approach for each clinical scenario.

Fluoroscopy↗
PubMed2000

Isolation of differentially expressed aldose reductase in ovaries after estrogen withdrawal from hypophysectomized diethylstilbestrol treated rats: increased expression during apoptosis.

More than 99% of the follicles are eliminated by apoptosis before reaching ovulation. Several growth factors and hormones inhibit apoptosis in the ovary, including estrogen. Using differential display of mRNA, aldose reductase was shown to increase in the ovary of diethylstilbestrol treated hypophysectomized rats after estrogen withdrawal, inducing apoptosis. The aldose reductase mRNA expression was confirmed to be 2.2 +/- 0.2-fold higher after estrogen withdrawal using northern blot analysis. In addition, untreated immature rats showed a 1.7 +/- 0.3-fold higher expression of ovarian aldose reductase mRNA compared to ovaries 24 h after pregnant mare's serum gonadotropin treatment, decreasing apoptosis in the ovary. In the prostate, the level of aldose reductase was increased 3.1 +/- 1.1-fold 2 days after castration induced apoptosis. Although the physiological role of aldose reductase in the ovary is not known, these data suggest that aldose reductase may be part of a hormonally regulated apoptotic pathway in the ovary and prostate.

Aldehyde Reductase↗
PubMed2000

Cancer pain education: the use of a structured clinical instruction module to enhance learning among medical students.

The Structured Clinical Instruction Module (SCIM) is an educational format developed for the teaching of clinical and interpersonal skills. The purpose of this study was to develop and pilot-test a SCIM to enhance medical students' learning and understanding about cancer pain assessment and management. The Cancer Pain SCIM was presented to 34 third-year medical students. Eight instructors and six standardized patients (five cancer patients) participated in the course. All participants evaluated the course using a five-point Likert scale (1 = strongly disagree; 5 = strongly agree). Students self-assessed their clinical skills before and after the course using a five-point scale (1 = not competent; 5 = very competent). Students agreed [mean (S.D.)] very strongly that the SCIM was a valuable educational experience [4.4 (0.56)] and that it was beneficial to use actual cancer patients in the SCIM [4.5 (0.63)]. Students believed their skills in the assessment and management of cancer pain significantly improved after the course. The SCIM is a valuable and novel instructional format to teach essential skills in the assessment and management of cancer pain to medical students.

Clinical Competence↗
PubMed2000

A collaborative approach to developing nursing skills to meet service needs.

Academics, educators and health service managers came together to explore, within their local area, the nature of the perceptions of beginning registered nurses (BRNs) and Nursing Unit Managers (NUMs) to the skills utilised by BRNs within the first six months of practice. A group of 71 BRNs and nine NUMs participated in a cross-sectional survey. BRNs were also asked to rate their preparedness in each particular skill, dependent on the method of teaching--theory/lectures, nursing laboratories and clinical experience. Some 21 skills, relating to medication/fluid administration and skin and wound care, were perceived by 95 per cent or more of the graduates as being used within the first six months. Similar perceptions existed for NUMs and BRNs for 52.4 per cent of the listed skills. Differences in perceptions have led to academics altering the scope of skills being taught and focusing assessment on critical skills for BRNs, and managers increasing awareness among NUMs as to the source of the differences and developing programs to improve clinical interpretation skills. Improvements in the experience of the BRN are likely to occur when all parties work together to bring about positive change. By Barbara Somerville,

Adult↗
PubMed2000

Evaluation of BioStar FLU OIA assay for rapid detection of influenza A and B viruses in respiratory specimens.

BACKGROUND: Demand for the rapid diagnosis of influenza infections has increased with the advent of the availability of neuraminidase antiviral therapy for influenza A and B. Several rapid assays that detect both influenza A and B are now available. OBJECTIVES: In this study we compared the performance of the BioStar FLU OIA assay to Bartels Viral Respiratory Screening and Identification Kit (Bartels Inc., Issaquah, WA), and cell culture. STUDY DESIGN: A total of 145 patient specimens for influenza virus detection submitted in either viral transport medium or in sterile containers were evaluated by the three methods. Specimen types included nasal washings, nasal swabs, sputum, throat swabs, and bronchial alveolar lavage (BAL) fluids. RESULTS: Fifty six positive specimens were identified based on culture and/or DFA. Of these, 30 specimens were positive by the OIA assay for an overall sensitivity of 54%. The OIA assay detected 48% (n = 21) of the 44 culture positive specimens and 81% (n = 29) of the 36 DFA positive specimens. Eighty six of the 89 culture/DFA negative samples were negative by the OIA assay (97% specificity). Analysis of the OIA assay sensitivity from samples submitted in M4 transport medium or in sterile containers revealed that M4 transport medium does not reduce the sensitivity of the OIA assay. Fifteen of the 27 positive samples submitted in M4 transport medium were positive by the OIA assay (56% sensitivity) compared to 15 of 29 positive samples transported in sterile containers (52% sensitivity). Twelve specimens were either culture and/or DFA positive for viruses other than influenza, but negative by the OIA assay, suggesting that there was no cross reactivity of the OIA assay with the other virus types recovered in this study. CONCLUSIONS: The overall excellent specificity of the BioStar FLU OIA allows for treatment of positive patients for influenza, however, a negative result should be confirmed by DFA and culture.

Animals↗
PubMed2000

Nicotinic receptors in dementia of Alzheimer, Lewy body and vascular types.

OBJECTIVES: Comparisons were made of nicotinic receptors in 3 major forms of dementia in old age. Although it is well established the involvement of nicotinic receptors in Alzheimer's disease (AD), their status in the other two main causes of dementia in old age-dementia with Lewy bodies (DLB) and vascular dementia (VaD) is not widely reported. METHODS: Temporal cortex was examined for epibatidine and alpha-bungarotoxin binding, and immunoreactivity of alpha4 and alpha7 nAChR subunits. RESULTS: There were selective abnormalities in nicotinic receptor subtypes in the disorders examined. In AD there is a loss of high affinity receptor binding, reflecting a selective loss of alpha4 subunit, but no change in alpha7 subunits. Similar abnormalities in ligand binding are also apparent in DLB. In the VaD series, there was no overall loss of epibatidine binding or immunoreactivity for alpha4 or alpha7 subunits. CONCLUSIONS: Loss of cortical receptor alpha4 subunit appears to be a characteristic feature of neurodegenerative dementia but not dementia of vascular origin. Since nicotinic receptors control cerebral vasodilation, the relative integrity of the receptors in VaD may auger well for nicotinic therapy in this disorder in which there is a cholinergic abnormality, to judge by the loss of the presynaptic enzyme.

Aged↗
PubMed2000

Gene expression analysis by massively parallel signature sequencing (MPSS) on microbead arrays.

We describe a novel sequencing approach that combines non-gel-based signature sequencing with in vitro cloning of millions of templates on separate 5 microm diameter microbeads. After constructing a microbead library of DNA templates by in vitro cloning, we assembled a planar array of a million template-containing microbeads in a flow cell at a density greater than 3x10(6) microbeads/cm2. Sequences of the free ends of the cloned templates on each microbead were then simultaneously analyzed using a fluorescence-based signature sequencing method that does not require DNA fragment separation. Signature sequences of 16-20 bases were obtained by repeated cycles of enzymatic cleavage with a type IIs restriction endonuclease, adaptor ligation, and sequence interrogation by encoded hybridization probes. The approach was validated by sequencing over 269,000 signatures from two cDNA libraries constructed from a fully sequenced strain of Saccharomyces cerevisiae, and by measuring gene expression levels in the human cell line THP-1. The approach provides an unprecedented depth of analysis permitting application of powerful statistical techniques for discovery of functional relationships among genes, whether known or unknown beforehand, or whether expressed at high or very low levels.

Cell Line↗
PubMed2000

Donor leukocyte infusions in acute lymphocytic leukemia.

Donor leukocyte infusion (DLI) has well-documented activity in CML but the role of DLI in other diseases is less well defined. To evaluate the strategy in acute lymphocytic leukemia (ALL) we evaluated 44 ALL patients from 27 centers who were treated with DLI. Patients with persistent or recurrent disease received DLI from the original marrow donor (30 matched related, four mismatched family, and 10 matched unrelated). Chemotherapy was given before DLI to 28 patients. Of 15 patients who received no pre-DLI chemotherapy, two achieved complete remissions, lasting 1112 and 764+ days. In four patients who received DLI as consolidation of remission induced by chemotherapy or immunosuppression-withdrawal, duration of remission post DLI was 65, 99, 195 and 672+ days. Of 25 patients who received DLI in the nadir after chemotherapy, 13 survived > or =30 days post DLI but did not achieve remission, seven died within less than 30 days post DLI, and five entered remissions that lasted 42, 68, 83, 90, 193 days. Seven patients who did not respond to the initial DLI received a second DLI; none of these patients attained durable remission. Eighteen of 37 evaluable patients developed acute GVHD and five of 20 evaluable patients developed chronic GVHD. Overall actuarial survival is 13% at 3 years. In conclusion, DLI has limited benefit in ALL. New approaches are needed in this group of patients.

Actuarial Analysis↗
PubMed2000

Donor leukocyte infusions for multiple myeloma.

Donor leukocyte infusion (DLI) has well-documented activity in CML, but the role of DLI in other diseases is less well defined. To evaluate the strategy in multiple myeloma (MM) we evaluated 25 MM patients from 15 centers who were treated with DLI. Patients with persistent or recurrent disease after allogeneic BMT received DLI from the original marrow donor (23 matched related, one mismatched family, and one matched unrelated). Chemotherapy was given before DLI in three patients. Two of 22 patients responded completely to DLI alone and three patients responded to the combination of DLI and chemotherapy. Nine patients who had not had sufficient disease control after DLI were given additional DLIs; five of these patients had either complete (two) or partial (three) responses. Thirteen of 25 evaluable patients developed acute GVHD and 11 of 21 evaluable patients developed chronic GVHD; all responders developed GVHD. No patients developed post-DLI pancytopenia. Four patients had responses which lasted >1 year after DLI, three patients had responses which lasted <1 year, and three patients had ongoing responses but with follow-up <1 year. In conclusion, DLI has anti-myeloma activity but the strategy is limited by no response or short duration of response in a significant percentage of patients and by significant GVHD in the majority of the responders.

Adult↗
PubMed2000

On the assessment of stability and patterning of speech movements.

Speech requires the control of complex movements of orofacial structures to produce dynamic variations in the vocal tract transfer function. The nature of the underlying motor control processes has traditionally been investigated by employing measures of articulatory movements, including movement amplitude, velocity, and duration, at selected points in time. An alternative approach, first used in the study of limb motion, is to examine the entire movement trajectory over time. A new approach to speech movement trajectory analysis was introduced in earlier work from this laboratory. In this method, trajectories from multiple movement sequences are time- and amplitude-normalized, and the STI (spatiotemporal index) is computed to capture the degree of convergence of a set of trajectories onto a single, underlying movement template. This research note describes the rationale for this analysis and provides a detailed description of the signal processing involved. Alternative interpolation procedures for time-normalization of kinematic data are also considered.

Adult↗
PubMed2000

Men's lived experiences following transurethral prostatectomy for benign prostatic hypertrophy.

The aim of this study was to illuminate the lived experience of prostatectomy recovery by means of semi-structured interviews. Despite the commonality of prostatic enlargement and the corrective transurethral procedure, surprisingly little is known of the impact upon the men's social and psychological well-being. The interviews have produced very rich data, which illustrate the extent to which the men are initially very reluctant to identify 'problems' either with their hospital experience or their subsequent recovery period. However, once respondents appeared to feel more comfortable, we began to learn of their very substantial difficulties both before and after the operation.

Aftercare↗
PubMed2000

Men making sense of their chest pain--niggles, doubts and denials.

Participant observation was undertaken of the early admission period of 25 men admitted to hospital with acute chest pain, followed by in-depth interviews of 10 of the men after discharge. Grounded theory methods were used in the analysis to develop a model of how the men came to interpret their experiences. An emerging feature of the men's experiences was that, although they had suffered intense pain prior to admission, there had been a series of delays whilst they tried to rationalize their symptoms. We relate our discussion to literature on men and masculinity and the notion of Foucault (1975) of self-surveillance, to offer an insight into the men's self concept and social situation. Our conclusions suggest that men's self concept as 'healthy' may inhibit a speedy response to the signs and symptoms of acute coronary occlusion, increasing the risk of cardiac arrest without nearby life support.

Chest Pain↗
PubMed2000

Feeding outcomes and influences within the neonatal unit.

This study examined the feeding intention of mothers (n = 100), and the factors and beliefs, and changes in those factors or beliefs that influenced their choices, in the challenging environment of the neonatal unit. Mothers' experience and the frequency of nurse-assisted feeding activities were examined in mothers intending and not intending to breast-feed on discharge. Eighty-one per cent of mothers were either partially or fully breast-feeding or intending to do so on discharge. The most important factors identified as influencing this feeding choice included personal choice, with other influences being special benefits, more natural and feeling closer to the baby. Experiences such as infants receiving their first sucking feed from either the breast or bottle (inclusive of breast milk) and mothers expressing breast milk more frequently, were found to be significantly different and increased in frequency, in mothers intending to breast-feed. Differences in the mean weighted total daily nurse-assisted feeding score confirmed that these activities varied with gestational age (< or = 32 weeks [2.57], 32 to less than 35 weeks [3.86], and > or = 35 weeks [4.91]; F = 7.04, d.f. 55, P = 0.002), although there was insufficient power to determine differences between breast-feeding and non-breast-feeding mothers. The use of the Feeding Activities Calendar may have contributed to increased activity and high levels of breast-feeding in this preterm group.

Adult↗
PubMed2000

Early detection of viral resistance by determination of hepatitis B virus polymerase mutations in patients treated by lamivudine for chronic hepatitis B.

We have analyzed the molecular dynamics of emergence of drug-resistant strains in patients receiving lamivudine therapy for chronic hepatitis B. Twenty consecutive patients with lamivudine resistance were studied (13 hepatitis B e antigen [HBeAg]-positive patients and 7 HBe antibody [anti-HBe]-positive patients). Determination of viral genotype, precore mutants, and polymerase gene mutants (L528M, M552V, M552I) was performed using the research version of Lipa-HBV. Quantitative analysis of HBV DNA was performed using both branched DNA (bDNA) and polymerase chain reaction (PCR) assays. Polymerase mutants (genotypic resistance) were found in 16 of 20 patients. Genotypic resistance was detected earlier than the phenotypic resistance (P =.004). Quantitative PCR allowed detection of viral DNA throughout the entire study period in 16 of 20 patients. Analysis of pretreatment variables showed that high alanine transaminase (ALT) levels (>3 x the upper limit of normal [ULN]) was associated with a more rapid selection of drug-resistant mutants (P =.027) and a high hepatitis B virus (HBV) DNA level (>1,497 Meq/mL, bDNA) with a more rapid occurrence of phenotypic resistance (P =.04). At the time of viral breakthrough, the mean serum HBV-DNA values were not different from the pretreatment values (P =.37). ALT levels were higher in anti-HBe-positive patients compared with pretreatment values and to HBeAg-positive patients (P =.01). In 8 patients, antiviral therapy was modified after viral breakthrough, with the introduction of famciclovir and/or interferon alfa. Viral DNA became undetectable by bDNA in 3 patients who received interferon. Our results suggest that genotypic assays for polymerase mutant detection and quantitative determination of viremia with highly sensitive assay are warranted for an optimal monitoring of antiviral therapy of chronic hepatitis B.

2-Aminopurine↗
PubMed2000

Low-dose inhaled fluticasone propionate versus oral zafirlukast in the treatment of persistent asthma.

BACKGROUND: Few studies have compared the efficacy of inhaled corticosteroids and leukotriene modifiers for the treatment of persistent asthma. OBJECTIVE: Our purpose was to compare the efficacy of a low dose of inhaled fluticasone propionate (FP) with that of oral zafirlukast in the treatment of persistent asthma previously treated with short-acting beta(2)-agonists alone. METHODS: A 12-week, randomized, double-blind, double-dummy, multicenter study was conducted in 451 patients aged 12 years and older with asthma who were symptomatic on short-acting beta(2)-agonists alone. After an 8- to 14-day run-in period, patients were randomized to treatment with FP 88 microg twice daily or zafirlukast 20 mg twice daily. RESULTS: Treatment with FP was more effective than treatment with zafirlukast in increasing morning FEV(1) (by 0.42 L vs 0.20 L over baseline, P <.001), morning peak expiratory flow (by 49.94 L/min vs 11.68 L/min over baseline, P <. 001), and evening PEF (by 38.91 L/min vs 10.50 L/min over baseline, P <.001). Statistically significant differences between the two treatments in FEV(1) were noted after the first observation (week 4) and in morning and evening peak expiratory flow by week 2. Mean change in percentage of symptom-free days was greater with FP than with zafirlukast (28.5% of days vs 15.6% of days, P <.001) and FP significantly increased the percentage of rescue-free days by 40.4% of days compared with 24.2% of days with zafirlukast (P <.001). Treatment with FP significantly reduced albuterol use by 2.39 puffs per day compared with 1.45 puffs per day (P <.001) and increased the percentage of nights with no awakenings by 21.2% of nights compared with 8.0% of nights with zafirlukast (P <.001). CONCLUSION: The clinical effectiveness of a low dose of FP as first-line therapy in patients with persistent asthma who are symptomatic on beta(2)-agonists alone is superior to that of zafirlukast.

Administration, Inhalation↗
PubMed2000

Bilingual health communicators: role delineation issues.

Managers of health care services are seeking new opportunities to improve communication with clients who have limited English proficiency. An increase in bilingual health staff and the frequent use of their language skills in patient encounters provides opportunities but also brings with it confusion surrounding the role of interpreters and bilingual health staff. Secondary analysis of transcripts from 18 focus groups with monolingual and bilingual health staff has provided a method of distinguishing the roles of these complementary communicators. This paper clarifies the roles of interpreters and bilingual communication facilitators using seven key features: scope of language, language proficiency, nature of communication/interaction, nature of the contact and relationship, client responsibilities, and relationship with other health care providers. We discuss differences in how bilingual health staff use language when providing care, and alternative types of interactions interpreters could adopt to extend their current role. A collaborative group of communicators located within a health team is proposed, that is able to identify need and select the best communicator for the task.

Communication↗