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J Ward

Publications and source records attributed to J Ward.

At least 397 records · Page 22Linked to original sources
PubMedDate not supplied

Planning for an adaptive design: a case study in COPD.

We discuss the practical and clinical considerations encountered when planning a Phase IIa trial in chronic obstructive pulmonary disease (COPD). Various adaptive strategies for reducing the cost of the trial and the statistical implications of these are explored. Use of the EAST software to evaluate the properties of the study designs with one or more interim analyses for futility, efficacy or either is described. We emphasize the rationale for choosing between alternative designs and the relationship between the clinical and statistical considerations.

Clinical Trials, Phase II as Topic↗
PubMedDate not supplied

Does a 3-day workshop for family medicine trainees improve preventive care? A randomized control trial.

OBJECTIVE: To evaluate the impact on clinical behavior of a 3-day workshop designed to increase trainees' rates of smoking cessation counseling and reminders about Pap smears in routine consultations. DESIGN: Randomized control trial. SETTING: Accredited teaching practices of the Royal Australian College of General Practitioners' Training Program. SUBJECTS: Thirty-four trainees and 1,500 consecutive adult patients ages 16-65 years. METHOD: Trainees randomly allocated to the experimental group participated in a 3-day interactive workshop on disease prevention during their 13-week family medicine term. Audiotapes of consultations with adults conducted by trainees at the beginning and end of the rotation were analyzed blind to compare assessment of patients' smoking status and, for women, date of last Pap smear. A questionnaire mailed to each patient after the consultation also allowed identification of smokers and women overdue for a smear. Consultations with these patients at risk were analyzed for preventive counseling. Inter- and intrarater reliability was calculated for audiotape analysis. RESULTS: Preworkshop rates of questions about smoking were low, occurring in 22% of consultations. While trainees allocated to the experimental workshop were more likely to ask a routine question about smoking at the end of the term than those in the control group (P = 0.01), two-thirds of smokers remained undetected irrespective of trainee group and fewer than one in five were advised to stop smoking. Reminders about Pap smears did not change as a result of training and remained low in fewer than 20% of consultations. kappa values demonstrated high reliability of audiotape analysis. CONCLUSION: This direct measurement of clinical behavior revealed that low levels of preventive care provided by trainees are resistant to skills training without reinforcement in clinical practice. In view of the importance of prevention in routine consultations, we recommend continued evaluation of more intensive educational programs. Those withstanding rigorous evaluation could be considered for implementation in similar training contexts seeking to improve the frequency and quality of disease prevention in primary medical care.

Adolescent↗
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Identification of HIV-infected transfusion recipients: the utility of crossreferencing previous donor records with AIDS case reports.

An expanded "look-back" program has been developed, in which patients who may have been exposed to HIV through blood transfusion were identified via three triggers: the blood that they received was donated by persons who 1) have subsequently been reported to local health departments as meeting the diagnostic criteria for AIDS, 2) have donated since the introduction of anti-HIV screening and tested positive, or 3) have been found to be infected during investigation of reported transfusion-associated HIV infections. In comparing triggers, cross-referencing the list of patients reported to have AIDS (AIDS case list) proved to be the most efficient approach for identifying HIV-infected donors and transfusion recipients. Of the 7973 AIDS patients reported in eight Northern California counties as of December 1988, 316 (4.0%) were determined to have donated at Irwin Memorial Blood Centers between 1977 and 1985. Despite the logarithmic increase in reported cases of AIDS in the San Francisco Bay area over the last 5 years, the rate of detection of previous donors from AIDS case lists remained between 3.3 and 5.4 percent. These persons accounted for 69 percent of the identified infected donors, and their identification led to notification of 60 percent of potentially exposed recipients and 51 percent of known infected recipients. The crossreferencing of AIDS case listings with blood bank records was equally efficient for regions with low and high AIDS prevalence. National adoption of AIDS case list crossreferencing is recommended as an effective means of identifying previously unidentified infected recipients in an effort to limit the secondary spread of HIV infection.

Acquired Immunodeficiency Syndrome↗
PubMedDate not supplied

Haemophilus influenzae disease and immunization in developing countries.

Haemophilus influenzae is one of the leading causes of severe bacterial infection in children of developing regions, causing 30% of the cases of culture-positive pneumonia and 20%-60% of the cases of bacterial meningitis. In infants and children, the majority of isolates from cerebrospinal fluid and blood and 16%-38% of pulmonary isolates are H. influenzae type b. The availability of several new polysaccharide-protein conjugate vaccines for the prevention of invasive disease due to H. influenzae type b prompts this review of the epidemiology of H. influenzae disease in the developing world and of the characteristics of current H. influenzae type b vaccines. To develop a strategy for use of H. influenzae type b vaccines in developing countries, the following data are needed: the age-specific attack rates of H. influenzae type b disease and the immunogenicity and efficacy of these vaccines in young infants in developing countries. Should H. influenzae type b vaccines prove to be inadequate for the prevention of H. influenzae pneumonia, the use of non-type b H. influenzae vaccines may be necessary.

Bacterial Capsules↗
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Antibiotic-resistant Streptococcus pneumoniae: clinical and epidemiologic aspects.

Antibiotic-resistant Streptococcus pneumoniae, particularly penicillin-resistant strains, are being identified with increasing frequency. Pneumococci with intermediate penicillin resistance (IPR) have been recovered from patients for 15 years. These strains have minimal inhibitory concentrations (MICs) for penicillin of 0.1-1.0 microgram/ml, an MIC that is 10-100 times greater than that for susceptible strains. However, in the past three years, resistant strains have been isolated that have MICs for penicillin of 2-10 microgram/ml. Disease caused by IPR strains may respond to high-dosage parenteral penicillin, but disease caused by more resistant strains, especially meningitis, requires therapy with alternative agents. Pneumococci resistant to tetracycline, sulfonamides, erythromycin, lincomycin, chloramphenicol, clinadmycin streptomycin, and rifampin have also been reported. Particularly ominous has been the development in South Africa of multiply resistant pneumococci, resistant to all the above agents, including all beta-lactam antimicrobial agents. This paper reviews the following aspects of resistant pneumococci: (1) the definitions of resistance and methods of susceptibility testing, (2) the geographic distribution of resistant strains, (3) the epidemiologic characteristics of infected patients, (4) the clinical manifestations of disease and response to therapy, (5) the distribution of serotypes and implications for use of the pneumococcal vaccine, and (6) the methods used to limit spread of resistant strains and to prevent disease. These new issues may alter the impression that pneumococcal disease is readily treated and no longer a major public health threat.

Anti-Bacterial Agents↗
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Color enhancement of multispectral MR images: improving the visualization of subcortical structures.

PURPOSE: The current investigation was undertaken to evaluate a new method for creating MR multispectral color images, which we call "Superimages." They were developed to improve the delineation of small brain structures composed of mixed tissue types, such as the basal ganglia. METHOD: To qualitatively validate the method, visual comparisons were made of six unimodal and multispectral images, including the Superimage. Quantitative validation was undertaken by comparing the reliability values for parcellation of the globus pallidus (GP) using either a gray scale (T1-weighted) image or the Superimage. RESULTS: Qualitative assessment of the Superimage revealed enhanced visualization of the GP, caudate, and putamen. Quantitative assessment resulted in good reliability for Superimage traces. CONCLUSION: The Superimage significantly improves both the visualization and the parcellation of structures visualized by MRI.

Adult↗
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Novel human MHC class I genes are expressed by tumour cell lines representing embryonic and extraembryonic tissues.

The expression of HLA class I(-like) genes was studied in two human developmental tumour cell lines representing embryonic (Tera-2) and extraembryonic (Jeg-3) origins. Neither cell line expresses polymorphic HLA-A, -B, -C antigens as determined by standard serological typing. Tera-2 cells express the HLA class I-like T cell system A (TCA) determinants; Jeg-3 cells are TCA negative. Northern blot analysis using an HLA class I alpha 3 domain specific probe revealed markedly reduced levels of HLA class I(-like) transcripts in both cell lines, which can be upregulated in Tera-2 cells by incubation with gamma interferon (gamma IFN). Immunoprecipitation studies with a large panel of HLA class I/beta-2 microglobulin (beta 2m) monoclonal antibodies (mAbs), detect low quantities of regular HLA class I heavy chains that are not associated with beta 2m on the surface of Tera-2 cells. In contrast, Jeg-3 cells express significant amounts of cell membrane beta 2m associated molecules of 41 and 45 kilodalton (kD). Screening of a Tera-2 cDNA library, yielded 30 clones that hybridize to a full length HLA class I cDNA probe. Sixteen have been characterized and represent HLA class I sequences, consistent with the haplotype of Tera-2. A similar screening of a Jeg-3 cDNA library isolated clones representing a single novel HLA-C-like sequence; this probably codes for the 45 kD cell surface molecules of Jeg-3. The 41 kD molecule may be encoded by the HLA-6.0 gene since this is constitutively expressed in Jeg-3 cells.

Choriocarcinoma↗
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Effect of the conformation of a peptide from gp41 on binding and domain formation in model membranes.

Binding of the peptide fragment 828-848 (P828), amino acid sequence RVIEVVQGACRAIRHIPRRIR, from the carboxy-terminal region of the envelope glycoprotein gp41 of human immunodeficiency virus type 1 (HIV-1) to membranes composed of a mixture of neutral and negatively charged phospholipids results in domain or cluster formation of the charged lipid. The conformation and dynamics of the peptide are investigated in solution and in the presence of sodium dodecyl sulphate (SDS) micelles using high resolution nuclear magnetic resonance (NMR) spectroscopy and circular dichroism (CD) spectropolarimetry. The CD results demonstrate that addition of either SDS, negatively charged phospholipid liposomes, or trifluoroethanol (TFE) induces a conformational transition of the peptide from a random coil or an extended chain in water to a more ordered structure with an estimated helical content of up to 60%. The structure of the peptide in a membrane mimetic SDS solution was investigated in detail using two-dimensional NMR. The measurements demonstrate the existence of a helical component in the peptide conformation in the SDS-bound state. The peptide most likely exists as an ensemble of conformations with exchange times between them which are fast on the chemical shift NMR time scale (10(-3) s). Simple neutralization of the six arginine sidechain charges does not cause the peptide to adopt an ordered structure. Thus, there is an additional requirement for the structural transition such as that resulting from constraint of the peptide on a surface, or localization of the peptide at the lipid-water interface where the polarity is lower.(ABSTRACT TRUNCATED AT 250 WORDS)

Amino Acid Sequence↗
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Screening for malnutrition.

This article recommends that screening for malnutrition is used in both primary care and hospital settings. The authors also outline how nurses are ideally placed to screen patients for evidence of malnutrition and to offer first line nutritional advice and care.

Algorithms↗
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Risk management and substandard clinical care.

Physicians must now openly demonstrate their competence and ability to perform their role as consultants. Measures have been developed which allow early identification of problems and provide procedures to examine in detail where and when problems arise. A number of organisations will be involved and efforts must be made to co-ordinate the various initiatives. One note of caution, however. Assuming that regular peer review is accepted, that CHI carry out a four-year cycle of visits to every trust in the land, that all visitors in such procedures have to be trained to do the job, that the visitors must be engaged in active clinical practice, that at home appraisal audit and assessment are in progress, the question inevitably arises as to where all the personnel will come from and what happens to clinical work in our under-doctored country? Change certainly stimulates excitement about the future.

Clinical Competence↗