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D Davis

Publications and source records attributed to D Davis.

At least 127 records · Page 7Linked to original sources

Report on activities and attitudes of organizations active in the clinical practice guidelines field.

The organizing committee of a workshop on clinical practice guidelines (CPGs) surveyed invited organizations on their attitudes and activities related to five topics to be covered during the workshop sessions: organizational roles, priority setting, guidelines implementation, guidelines evaluation and development of a network of those active in the CPG field. Organizational roles: The national specialty societies were felt to have the largest role to play; the smallest roles were assigned to consumers, who were seen to have a role mainly in priority setting, and to industry and government, both of which were seen to have primarily a funding role. Many barriers to collaboration were identified, the solutions to all of which appeared to be better communication, establishment of common principles and clear role definitions. Priority setting: There was considerable agreement on the criteria that should be used to set priorities for CPG activities: the burden of disease on population health, the state of scientific knowledge, the cost of treatment and the economic burden of disease on society were seen as important factors, whereas the costs of guidelines development and practitioner interest in guidelines development were seen as less important. Organizations were unable to give much information on how they set priorities. Guidelines implementation: Most of the organizations surveyed did not actively try to ensure the implementation of guidelines, although a considerable minority devoted resources to implementation. The 38% of organizations that implemented guidelines actively listed a wide variety of activities, including training, use of local opinion leaders, information technology, local consensus processes and counter detailing. Guidelines evaluation: Formal evaluation of guidelines was undertaken by fewer than 13% of the responding organizations. All the evaluations incorporated assessments before and after guideline implementation, and some used primary patient data. Barriers to evaluation included lack of money, time, data or expertise. CPG Network: Most of the respondents felt that all organizations and individuals interested or involved in guidelines should form the membership of the network. The three most important functions of such a network were deemed to be (a) to facilitate collaboration among those involved in the CPG process, (b) to maintain an information centre on CPGs and (c) to provide expertise to the CPG process. It was felt that the network should have some formal structure and communicate through e-mail and print media.

Attitude↗

Relocation of the carboxyterminal part of CAN from the nuclear envelope to the nucleus as a result of leukemia-specific chromosome rearrangements.

Fusion genes encoding the 3' part of the can gene are implicated in two types of leukemia. The dek-can fusion gene is present in t(6;9) acute myeloid leukemia and the set-can fusion gene is present in one case of acute undifferentiated leukemia. In order to obtain leads towards the molecular basis of these diseases, we have studied the cellular localization of the DEK-CAN and SET-CAN fusion proteins and their normal counterparts. DEK-CAN and SET-CAN were localized exclusively in the nucleus, and also DEK and SET were found to be nuclear proteins. However, CAN was mainly located at the nuclear and cytoplasmic face of the nuclear envelope. This observation is in accordance with the presence of an amino acid repeat in the C-terminal part of CAN, common to the family of nucleoporins. The C-terminal part also contains a nuclear location domain as shown by deletion analysis. This domain may be important for the presence of CAN at the nucleoplasmic side of the nuclear envelope. The relocation of the carboxyterminal part of CAN due to DEK-CAN and SET-CAN may reinforce a nuclear function of the CAN protein.

Acute Disease↗

Correlation of rapid changes in the average water diffusion constant and the concentrations of lactate and ATP breakdown products during global ischemia in cat brain.

Rapid changes in the average water diffusion constant, Dav = 1/3[Dxx+Dyy+Dzz], and in the concentrations of lactate and purine nucleotides and nucleosides were measured upon global ischemia (cardiac arrest) in cat brain, at a combined time resolution of 36 s (n = 7). At this time resolution, the normalized time curves of 1 - Dav and the increase in ATP breakdown product did not coincide, with the changes in Dav being most rapid. The normalized curves of 1 - Dav and the lactate increase coincided for the first 2-2.5 min after which the change in Dav was more rapid. After this time point, an excellent correlation was found between the drop in Dav and the decrease in energy utilization rate, which was calculated from the measured time curves of lactate formation and ATP breakdown, and from the time curve for phosphocreatine use reported in the literature. These results are in agreement with the expected biphasic changes in ion and water homeostasis during ischemia and with the model of diffusional changes being a consequence of a water shift from interstitial to intracellular space.

Adenosine Triphosphate↗

Serological diagnosis of feline immunodeficiency virus infection using recombinant transmembrane glycoprotein.

We developed an antibody detection enzyme-linked immunosorbent assay (ELISA) using recombinant surface (SU), transmembrane (TM) and capsid (CA) antigens of feline immunodeficiency virus (FIV) expressed in Escherichia coli. The three antigens were tested with sera collected from experimentally infected cats in order to follow the course of seroconversion and of the antibody levels throughout the infection. An early and marked increase of TM antibodies was observed. Antibodies to TM were demonstrated at high levels throughout the observation period. The immune response to SU and to CA was less pronounced and in some cats the level of antibodies to SU and CA tended to decline 6 months after infection. In addition, 413 FIV negative and positive cat sera were tested in order to define for each antigen the diagnostic sensitivity, specificity and efficiency. TM showed the highest diagnostic sensitivity (98%) while its specificity was 97%. Its diagnostic efficiency of 97% was better than that of SU and CA and exceeded that of tests utilizing conventionally grown and gradient purified FIV. Therefore, recombinant TM can be considered a very important antigen for FIV ELISA testing. An interesting perspective is offered in the combination of TM with other recombinant antigens in a dot assay form.

Animals↗

FIV vaccine studies. I. Immune response to recombinant FIV env gene products and outcome after challenge infection.

We have vaccinated five groups of cats (n = 25) four times with five preparations of recombinant feline immunodeficiency virus (FIV) env gene products; one group (n = 7) served as control. The vaccine formulations were as follows: (1) envelope glycoprotein of FIV Zurich 2 (FIV Z2) expressed in a Baculovirus system and isolated by gel electroelution (denatured form); (2) insect cells expressing FIV Z2 glycoprotein; (3) envelope glycoprotein of a Boston strain (FIV Bangston) expressed in insect cells and isolated by gel electroelution (denatured form); (4) glycosylated Bangston envelope protein made in insect cells and isolated in a native form; (5) non-glycosylated Bangston envelope protein made in Escherichia coli. All cats were challenged with 20 50% cat infective doses (CID50) of FIV Z2 previously titrated in cats. All vaccinated cats developed high enzyme-linked immunosorbent assay (ELISA) antibodies to the homologous antigen; crossreactivity to heterologous antigens was seen at a lower level. Virus neutralizing antibodies (tested with Petaluma virus) reached titers up to 32. After challenge, all cats seroconverted (as judged by anti gag antibodies in Western blot) and became infected (as judged by virus isolation and/or polymerase chain reaction) between 4 and 11 weeks with the exception of one cat. It is concluded that it is relatively easy to induce high ELISA antibody titers using recombinant env gene products, ELISA antibody titers do not correlate with virus neutralization or with protection.

Animals↗

An experimental chemically inactivated HIV-1 vaccine induces antibodies that neutralize homologous and heterologous viruses.

We have developed a unique multiple step procedure to inactivate human immunodeficiency virus chemically with a very high safety margin while retaining antigenically active structural virion proteins, including gp120, in the final immunogen. The whole virus preparation (1-10 micrograms per dose) was highly immunogenic in a variety of small mammals and induced antibodies that recognized homologous and heterologous strains of HIV-1. Sera from immunized animals bound to peptides representing the entire sequence of the external glycoprotein gp120. Neutralizing antibodies active against the homologous immunizing strain and against heterologous HIV-1 strains were also elicited. Sera with virus neutralizing activity did not bind to MHC class I proteins derived from the human cell line used to grow the virus.

AIDS Vaccines↗

Independent practice: a critical analysis and a personal journey.

This paper describes the personal journey of one independent practitioner as she moved from the environment of hospital practice and training to that of an independent practitioner. Many of the difficulties encountered on this journey can best be understood by reflection on the social, historical and political context in which nursing, midwifery and women experience their world. Critical theory offers midwifery the opportunity to more fully understand our worlds and to move beyond the dominant social order and reconstruct our social worlds in more just and liberating ways.

Australia↗

Ways of knowing in midwifery.

Scientific ways of knowing dominate our society today and this has major ramifications for midwifery. This article outlines the historical development and cultural understanding of ways of knowing in our society today. It is suggested that the patriarchal societies in which our ways of knowing have developed have emphasised scientific ways of knowing while other ways such as intuition and embodied knowledge received little acknowledgement. This article then goes on to explore these other ways of knowing, discusses their implications for midwifery care and suggests that to embrace many and varied ways of knowing is to more fully realise our abilities and potential as midwives.

Cultural Characteristics↗

Lymphocytotropic strains of HIV type 1 when complexed with enhancing antibodies can infect macrophages via Fc gamma RIII, independently of CD4.

Antipeptide sera raised against the gp120/gp41 sequences of human immunodeficiency virus type 1 (HIV-1) were used to determine their capacity to enhance infection. Antisera to the five variable regions (V1 to V5) of gp120 and conserved parts of gp120 and gp41 facilitated infection of primary human macrophages with the homologous virus HIV-1 SF2mc. In contrast, heterologous virus infection with HTLV-IIIB was mediated only by antisera to the conserved regions, predominantly C4 and C5. Heterologous virus infection occurred more rapidly and was consistent between different cell donors. The neutralizing monoclonal antibody (MAb) SC258 (murine IgG2a) but not MAb 684-238 (mIgG1) against conformational epitopes of the V2 region also induced antibody-dependent infection enhancement (ADE). Therefore, preincubation with certain antibodies can cause altered tropism of the lymphocytotropic viruses mentioned above. Viral infection was completely abolished by preincubation with the F(ab)2 fragment of MAb 3G8 against the Fc gamma receptor III (CD16). A MAb (7.3F11) against the gp120-binding site of CD4 had no effect on viral infectivity. Possible mechanisms and their implications for disease progression are discussed.

Acquired Immunodeficiency Syndrome↗

Increased middle cerebral artery flow velocity during the initial phase of cardiopulmonary bypass may cause neurological dysfunction.

One hundred twenty-seven patients undergoing coronary artery bypass graft surgery were monitored by transcranial Doppler ultrasonography. Five patients had more than 50% increases in middle cerebral artery mean flow velocity during the initial phase (10-120 sec) of cardiopulmonary bypass. Four of these 5 developed neurological complications including stroke and encephalopathy. These results indicate that overperfusion of the basal cerebral arteries during cardiopulmonary bypass procedures may contribute to neurological dysfunction after the surgery.

Adult↗

Identification of the sites of N-linked glycosylation on the follicle-stimulating hormone (FSH) receptor and assessment of their role in FSH receptor function.

The FSH receptor (FSHR) contains a large extracellular domain in which exist three potential sites for N-linked glycosylation. A truncated form of the FSHR representing only the extracellular domain was created and expressed in mammalian cells. We show that this truncated receptor is glycosylated, through the carbohydrates are not as fully processed as those of the full-length receptor. This truncated receptor, which remains intracellular, binds FSH with an affinity comparable to that of the full-length FSHR. Therefore, although other regions of the FSHR may contribute to hormone binding, the extracellular domain alone can confer high affinity binding. The above results suggest that N-linked FSHR carbohydrates may, in some way, be required for FSH binding. Therefore, further experiments, done in the context of the full-length receptor, were performed to determine the actual sites of glycosylation in the FSHR as well as to elucidate their role in the functions of the FSHR. Site-directed mutagenesis was done to individually or collectively disrupt the potential sites for N-linked glycosylation. Western blot analyses of the wild type vs. mutant receptors demonstrate that, of the three potential sites for N-linked glycosylation, Asn's 174 and 276 are actually glycosylated. Binding assays demonstrate that these two N-linked FSHR carbohydrates are redundant in function since carbohydrate at either Asn174 or Asn276 allows the receptor to be expressed on the cell surface and to bind FSH with normal affinity. However, FSH binding activity is not observed with nonglycosylated mutant receptors where both sites have been collectively disrupted. Similarly, when cells expressing the wild type FSHR were treated with tunicamycin to prevent N-linked glycosylation, the resulting nonglycosylated FSHR was not able to bind FSH. In contrast, normal high affinity binding of FSH was maintained when N-linked carbohydrates were enzymatically removed from wild type receptors. Our results demonstrate that while N-linked carbohydrates on the FSH receptor are not required directly for the binding of hormone, a carbohydrate at either Asn174 or Asn276 is required for the efficient folding of the nascent receptor protein into a conformation that allows high affinity binding of hormone.

Amidohydrolases↗

Cardiac rehabilitation as secondary prevention. Agency for Health Care Policy and Research and National Heart, Lung, and Blood Institute.

This Quick Reference Guide for Clinicians highlights the conclusions and recommendations from Cardiac Rehabilitation, Clinical Practice Guideline No. 17, which was formulated by a panel representing the major health care disciplines involved in cardiac rehabilitation. The conclusions and recommendations were derived from an extensive and critical review of the scientific literature pertaining to cardiac rehabilitation, as well as from the expert opinion of the panel. This guide addresses the role of cardiac rehabilitation and the potential benefits to be derived in the comprehensive care of the 13.5 million patients with heart disease in the United States, as well as the 4.7 million patients with heart failure and the several thousand patients undergoing heart transplantation. This Quick Reference Guide for Clinicians highlights the major effects of multifactorial cardiac rehabilitation services: medical evaluation; prescribed exercise; cardiac risk factor modification; and education, counseling, and behavioral interventions. The outcomes of and recommendations for cardiac rehabilitation services are categorized as to their effects on exercise tolerance, strength training, exercise habits, symptoms, smoking, lipids, body weight, blood pressure, psychological well-being, social adjustment and functioning, return to work, morbidity and safety issues, mortality and safety issues, and pathophysiologic measures. Patients with heart failure and after cardiac transplantation, as well as elderly patients, are specifically addressed. Alternate approaches to the delivery of cardiac rehabilitation services are presented.

Aged↗

Rapid monitoring of changes in water diffusion coefficients during reversible ischemia in cat and rat brain.

Changes in the diffusion constant of water during reversible brain ischemia and cardiac arrest were monitored with a 10-s time resolution. Results (five cats, three rats) indicate that these changes are reversible and that the bulk of the changes are not caused by temperature or motion related to brain pulsations and blood flow. The rapid time course of the changes corresponds to the known time course for changes in energy state, signal transduction, and ionic homeostasis.

Animals↗

Melatonin-like immunoreactivity in the presence of different chemicals as determined by the radioimmunoassay.

To determine the nature of the molecule(s) that is responsible for the melatonin-like immunoreactivity (MLI), we measured the effect of pretreatment of plasma samples with detergents, reducing agent, and proteinase K. Nonidet P-40 Triton X-100, and ethylacetate extraction had no effect, while sodium deoxycholate, sodium dodecyl sulfate, beta-mercaptoethanol, ether extraction, proteinase K, and temperature increased the MLI. Since the radioimmunoassay (RIA) was sensitive to proteinase K, ionic detergents, and a reducing compound, we hypothesize that a proteinaceous molecule might be responsible for this MLI. We compared our column procedure for RIA of plasma melatonin (1) with procedures involving extraction with either ethylacetate or ether. In our hands preextraction of samples with organic solvents caused a loss of immunoreactivity. We also found that passing samples through the column is more efficient in eliminating interference in the melatonin assay than extracting samples either with ethylacetate or ether.

Chromatography↗

Effects of illness attribution and depression on the quality of life among persons with serious mental illness.

Attributing one's problems to a mental illness is associated with reduced subjective quality of life (QOL) among persons with schizophrenia, controlling for a broad range of socio-demographic, social, clinical, and psychosocial variables. Persons who attributed their problems to a 'physical, medical, or biological' problem in contrast to a 'mental illness' reported more positive social relations and higher overall quality of life. Much of the negative effect of mental illness attributions is explained by perceived stigma, lower self-esteem, and a higher level of depressive symptomatology. Depressive symptoms have an independent negative effect on QOL net of all other variables. These findings have important implications for the appropriate rehabilitation of persons with mental illness and require further scrutiny with prospective data.

Adult↗