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Biomedical subjects

P Davis

Publications and source records attributed to P Davis.

At least 469 records · Page 26Linked to original sources
PubMedDate not supplied

Interaction of D-penicillamine with gold salts: in vivo studies on gold chelation and in vitro studies on protein binding.

Serum and urinary gold levels were monitored in 18 patients previously treated with gold salts for rheumatoid arthritis and the effects of D-penicillamine studied. There was no statistically significant change in urinary gold levels on D-penicillamine therapy although there were some individual variations. Serum gold levels fell during D-penicillamine therapy but the rates of fall did not differ from those seen in patients not treated. In vitro studies on protein binding of gold salts suggest that a high affinity exists between gold salts and albumin with low levels of unbound gold even at concentrations far exceeding those seen in vivo. These preliminary results suggest that at therapeutic levels only small amounts of gold are available for chelation by penicillamine. It is concluded that penicillamine at low dosage is an unreliable chelator of gold salts in vivo and its use in the management of gold toxicity remains speculative.

Arthritis, Rheumatoid↗
PubMedDate not supplied

The impact of the new subsidy regime in general practice in New Zealand.

The first substantial change in the New Zealand health care reforms was the introduction in February 1992 of a new subsidy and charging regime in general practice. The paper reports on a comparison of data collected before and after the changes, drawing on GP-patient encounter information. Overall, seasonally adjusted levels of utilisation were maintained in the stage before the introduction of the new regime, declined 15% immediately following the changeover and stabilised thereafter. All patient groups were affected by the decline. Although the elderly were temporarily exempt from the changes, their consultations fell by 10%. Utilisation among beneficiaries--minor gainers from the changes--dropped by 30%. Children were more affected overall, adults less so. There was also some suggestion of greater falls for the lowest socio-economic groups. Activities under the direct control of the practitioner--prescribing and the ordering of tests--showed either little turbulence or no clear pattern of change. It is concluded that, although primary care subsidies and charges had been reshaped to favour poorer people, six months after the introduction of these changes there had been no corresponding redistribution of medical care consumed. Indeed, there is a suggestion that some of the groups ostensibly the target of increased assistance may have been adversely affected by the overall decline in utilisation.

Attitude to Health↗
PubMedDate not supplied

Case study. Erythropoietin for anaemia in a preterm Jehovah's Witness baby.

An infant born at 24 weeks gestation to Jehovah's Witness parents was made a Ward of Court and treated against their wishes with blood products. Erythropoietin was used without obvious benefit, but the child did well. The parents did not reject the child and maintained a good relationship with medical and nursing staff. We present this case in the light of current discussions on child welfare and recent reform of the law relating to child protection and highlight the many difficult dilemmas faced by the medical team.

Anemia, Neonatal↗
PubMedDate not supplied

Effective adjuvant chemotherapy for advanced nasopharyngeal carcinoma in children: a final update of a long-term prospective study in a single institution.

PURPOSE: The purpose of this study was to determine the efficacy and toxicity of a doxorubicin/cyclophosphamide-based chemotherapy and local radiation therapy in children with locally advanced or metastatic nasopharyngeal carcinoma (NPC). PATIENTS AND METHODS: Twelve patients aged 6 to 20 years old were treated with a chemotherapy regimen comprised of vincristine (1.5 mg/m2) and doxorubicin (45 mg/m2) on day 1 and cyclophosphamide (210 mg/m2) and 5-fluorouracil (240 mg/m2) on days 1 to 5. Chemotherapy was administered every 3 weeks for 1 to 2 years. Radiotherapy to the primary site (59 to 68 Gy) and to the neck (59 to 66 Gy) was given before or after 2 to 4 courses of chemotherapy. RESULTS: All patients achieved a complete response 4 to 16 months from the start of therapy (median 7 months). Nine patients have remained tumor free from 2 to 21 years (median 11 years) from diagnosis. One child was lost to follow-up and one died of tuberculosis; both were disease-free. One child developed a secondary osteosarcoma in the left mandible. Chemotherapy caused grade 4 neutropenia and thrombocytopenia in four patients. There were no therapy-related deaths and the most common late effect of therapy was neck fibrosis, which was observed in all patients. We conclude that the chemotherapy and radiotherapy regimen used in this study is highly effective for children and adolescents with locally advanced NPC and is associated with tolerable toxicity.

Adolescent↗
PubMedDate not supplied

Effect of elastase on the directional migration of lung fibroblasts within a three-dimensional collagen matrix.

Interactions between airway epithelial cells and bronchial fibroblasts often require close proximity between these cells. Previous studies have demonstrated that airway epithelial cells direct the migration of lung fibroblasts, but the factors that regulate this process during airway injury are not clear. We hypothesized that exposure of culture substrates to proteolytic enzymes, like those present in the inflamed airway, would increase fibroblast recruitment. We also postulated that elastase might affect the epithelium's ability to attract fibroblasts. We used an in vitro model with fibroblasts embedded between two layers of collagen gel to investigate their migration. Embedded fibroblasts exposed to culture medium alone (baseline) had a slight downward migration (migration directed to the upper gel layer expressed as a percentage of total migration was -2.8 +/- 1.4), but medium supplemented with porcine pancreatic elastase (PPE) resulted in a slight upward migration (2.0 +/- 1.4). When airway epithelial cells were cultured on the upper gel surface, the index of directed migration toward them was 15.9 +/- 1.3. Addition of PPE to the culture medium resulted in a significant increase to 22.3 +/- 1.5 (p < .05). Human neutrophil elastase (HNE) produced similar results, and these effects were inhibited by alpha 1-proteinase inhibitor. Similarly, total fibroblasts per 20 high-powered fields were counted in all conditions, suggesting that mitogenic interactions were not important in this system. The percentage of the total fibroblasts migrating at least 5 microns in any direction was also similar in all groups, suggesting chemokinetic mechanisms were not involved. These data suggest that elastase exposure in a model of the human airway increases directed fibroblast migration through the extracellular matrix. This phenomenon may play a role in the development of subepithelial fibrosis seen in inflammatory airway diseases like asthma.

Animals↗
PubMedDate not supplied

A nursing model for orthopaedics.

A nurse manager, an educationalist and a clinician describe their nursing model, which has been implemented on an orthopaedic unit. Based on an appreciation of the unique nature of the nurse-patient relationship, the model aims to foster and develop patient empowerment as a means of encouraging rehabilitation.

Humans↗
PubMedDate not supplied

Pain: opening up the gate control theory.

Despite the frequency with which nurses encounter patients with pain, there is evidence that they still fail to understand some of the theories and mechanisms governing pain production and control. This article offers an update on one such theory, the gate control theory, widely considered to be one of the most influential to practitioners.

Brain↗
PubMedDate not supplied

Managing brachial plexus injuries.

People who are injured in severe traumatic incidents such as motorcycle accidents and knife or gunshot attacks generally require intensive, life-saving surgical intervention for head, chest or spinal injuries. One of the problems associated with such accidents is brachial plexus injury. Although this does not pose a threat to life, it can result in chronic hand and arm disability and pain. The author describes the surgical and nursing management of these devastating injuries.

Accidents↗
PubMedDate not supplied

How to define levels of nursing practice.

This article describes the attempts of a joint working group (Box 1) to define what is meant by levels of practice within orthopaedic and pain management nursing, and to generate discussion among nurses. The group has produced a grid system which they believe successfully links practice level to academic ability.

Accreditation↗
PubMedDate not supplied

In vivo and in vitro effects of gold salts on lymphocyte transformation responses and antibody dependent cell-mediated cytotoxicity.

In vivo, gold salts have been shown to induce disease remission in rheumatoid arthritis. In some patients, this is associated with a return to normal of suppressed lymphocyte responses to mitogens and antigens. This study demonstrates that gold salts will suppress lymphocyte transformation in vitro but do not affect antibody dependent cell-mediated cytotoxicity. This suppression appears to be dose-related. In contrast to previous studies, evidence is provided to suggest that the suppression of lymphocyte responses by gold may at least in part be due to a direct toxic effect of myochrisine on the cultured cells.

Antibody-Dependent Cell Cytotoxicity↗
PubMedDate not supplied

The in vivo effect of nonsteroidal anti-inflammatory drugs, gold sodium thiomalate and methotrexate on neutrophil superoxide radical generation.

The generation of superoxide radicals by activated peripheral blood polymorphonuclear leukocytes from patients with rheumatoid arthritis (RA) has been measured and the in vivo effect of nonsteroidal anti-inflammatory drugs (NSAIDs) and disease remittive agents studied. Generation of superoxide radicals from RA patients was significantly decreased when compared to a control population. This was principally due to the disease rather than medications in that patients with osteoarthritis receiving NSAID generated superoxide radicals similar to that seen in the control group. RA patients receiving NSAIDs and injectable gold or methotrexate therapy showed a significant trend to normalization of superoxide radical generation when compared to those with RA receiving NSAIDs alone. We conclude that the reduced generation of superoxide radicals on activated polymorphonuclear leukocytes from patients with RA is principally a feature of the disease and that this abnormality can be partially reversed by the use of a disease remittive agent in vivo.

Adult↗
PubMedDate not supplied

A model of computer documentation of hospital specialty rotations.

The importance of a comprehensive documentation system for assisting residents in securing hospital privileges has been widely asserted. Other applications of a documentation system such as encouraging research, providing individual resident evaluations, and providing program evaluation are also worthy reasons for developing a system. This paper describes a computerized system for documenting the inpatient rotation experiences of family practice residents and discusses its potential applications. An example of curriculum evaluation as a use of a documentation system is detailed.

Computer Systems↗
PubMedDate not supplied

Hypergastrinemia in rheumatoid arthritis.

Fasting hypergastrinemia was noted in 13-41% of 82 of outpatients with definite or classical rheumatoid arthritis. No differences were noted between the normogastrinemic and the hypergastrinemic subjects in their age, sex, duration of rheumatoid disease, serological status, or medications. The food-stimulated gastrin response was 117 mg/L, or 216% above the basal levels, and the integrated gastrin response was increased to the level previously reported in patients with duodenal or gastric ulcer disease. These results suggest that hypergastrinemia is a feature of patients with rheumatoid arthritis, the gastrin response to food may be abnormal in some rheumatoid patients.

Adult↗