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C Green

Publications and source records attributed to C Green.

At least 127 records · Page 7Linked to original sources
PubMed1998

The use of QALY and non-QALY measures of health-related quality of life. Assessing the state of the art.

There are now a large number of instruments available for assessing health-related quality of life, many of which are used within economic evaluations. When considering the use of quality-of-life instruments, meaningful questions need to be asked to determine whether an instrument has been used judiciously. Such questions should consider whether the instrument is valid and suitable for the particular study question, whether the instrument is compatible with the economic evaluation framework used, and subsequently whether the conclusions presented in the study are legitimate. In order to illustrate the value of these questions we have applied them to a number of economic evaluations. The studies used were identified via a systematic review of the health economics literature. In our assessment of a sample of published material, we found that reporting is frequently unhelpful and that the inappropriate use of instruments and techniques casts doubt on the conclusions of economic evaluations. Furthermore, our systematic review of the health economics literature has shown that the general format of reported economic evaluations falls short of the commonly accepted ideal. We examined the health economics literature for 1995 and only identified a handful of studies which satisfied the economic evaluation criteria as accepted by most economists. It is hoped that raising awareness of these issues will urge evaluators, referees and publishers not to lose sight of the needs of the decision-maker when considering the detail which should be present in a reported evaluation.

Economics↗
PubMed1998

What is the outcome of the outcomes? Evaluation of the therapy outcome measures.

In 1996, the Speech and Language Therapy Departments of First Community Health NHS Trust and Kidderminster Care NHS Trusts agreed to take part in a year's pilot study of the Therapy Outcome Measures developed by Enderby and John (1997). This paper will discuss the rationale for choosing to pilot these outcome measures and discuss the implementation of the project from a service manager's perspective. The discussion will focus upon what has been learnt from piloting the Therapy Outcome Measures.

Evaluation Studies as Topic↗
PubMed1998

Umbilical arterial and venous catheters: placement, use, and complications.

Umbilical catheters have been used in NICUs for drawing blood samples, measuring blood pressure, and administering fluid and medications for more than 25 years. Complications associated with umbilical catheters include thrombosis; embolism; vasospasm; vessel perforation; hemorrhage; infection; gastrointestinal, renal, and limb tissue damage; hepatic necrosis; hydrothorax; cardiac arrhythmias; pericardial effusion and tamponade; and erosion of the atrium and ventricle. A review of the literature provides conflicting accounts of the superiority of high versus low placement of umbilical arterial catheters. This article reviews the current literature regarding use of umbilical catheters in neonates. It also highlights the policy developed for the authors' NICU, a 34-bed tertiary care unit of a children's hospital, and analyzes complications associated with umbilical catheter use for 1 year in that unit.

Catheterization, Peripheral↗
PubMed1997

Selegiline in the treatment of behavioural disturbance in Alzheimer's disease.

OBJECTIVE: The purpose of this study was to examine the behavioural and cognitive effects of selegiline in a group of moderately behaviourally disturbed AD patients. DESIGN: This was a 14-week randomized double-blind placebo-controlled study of selegiline (10 mg) and placebo. SETTING: An outpatient clinic in an urban-based tertiary referral centre in the USA. PATIENTS: Twenty-five outpatients meeting NINCDS criteria for probable Alzheimer's disease with associated behavioural disturbance. MEASURES: The Brief Psychiatric Rating Scale (BPRS), the Dementia Mood Assessment Scale (DMAS) and the Alzheimer Disease Assessment Scale (Cognitive) (ADAS-COG). RESULTS: In the primary analysis, improvement on the BPRS and DMAS scores with selegeline treatment did not. reach statistical significance. A secondary analysis using a parallel design showed a significant benefit of drug treatment on BPRS scores with a trend towards improvement on the DMAS. Among the 10 subjects who could be tested, there was a significant improvement in cognitive function on the ADAS-COG with selegiline compared to placebo. CONCLUSIONS: Short-term selegiline treatment produced an improvement in behaviour and had a significant effect on cognition in a subset of testable patients.

Aged↗
PubMed1997

Coronary revascularization surgery after myocardial infarction: impact of bypass surgery on survival after thrombolysis. GUSTO Investigators. Global Utilization of Streptokinase and Tissue Plasminogen Activator for Occluded Coronary Arteries.

OBJECTIVES: This study sought to investigate the impact of surgical revascularization on outcome after myocardial infarction. BACKGROUND: Small variations in rates of coronary artery bypass graft surgery (CABG) were noted among thrombolytic regimens in the Global Utilization of Streptokinase and Tissue Plasminogen Activator for Occluded Coronary Arteries (GUSTO) trial, prompting the question of whether survival differences were partly related to differences in CABG rates. METHODS: Patients in the GUSTO trial were randomized to one of four thrombolytic strategies. Of 40,861 patients with complete data, 3,526 underwent surgical revascularization during their initial hospital admission. Thirty-day and 1-year mortality rates were estimated using Kaplan-Meier techniques, and the impact of CABG as a time-dependent covariate on death was evaluated using a Cox survival model, adjusting for baseline prognostic factors. RESULTS: The median time from study enrollment to CABG was 7 days across treatment groups. A 15% reduction in mortality for the tissue-type plasminogen activator (t-PA)-treated group was evident by the seventh day. Bypass surgery was a significant independent predictor of 30-day mortality (risk ratio 1.87) and a weaker predictor of 1-year mortality (risk ratio 1.21). Operative mortality was highest in patients with acute mitral regurgitation, ventricular septal defect or poor left ventricular function and in those undergoing CABG within the first 4 days of randomization. CONCLUSIONS: The survival benefit of accelerated t-PA was not related to surgical revascularization. Bypass surgery was associated with excess mortality in the first year, but the added short-term mortality associated with CABG may be balanced by anticipated long-term benefit in specific groups of patients.

Aged↗
PubMed1997

Molecular basis of the D variant phenotypes DNU and DII allows localization of critical amino acids required for expression of Rh D epitopes epD3, 4 and 9 to the sixth external domain of the Rh D protein.

The discovery of Rh partial D variant red cells by discrepant reactions with different monoclonal anti-D has demonstrated the range of Rh D epitopes that have arisen due to alterations in Rh D protein structure. There are two current classification systems, one which uses a nine epitope model (epD1-epD9) whereas a more recent model proposes 30 different epitopes. We describe here the molecular basis of two D variants which lack epD4 and epD9 namely the DNU and D(II) phenotypes. These would have both been originally classified as D(II) phenotype individuals, but we have revealed subtle differences in the serological profile of these erythrocytes. Such a differential reactivity and determination of the molecular bases of these phenotypes allows us to predict critical amino acids for epD3, epD4 and epD9 expression. The DNU phenotype arises from a single point mutation in the RHD gene resulting in a single amino acid change (Gly353Arg). Sequence analysis of exon 7 of the RHD gene derived from the D(II) propositus indicates that there is a single point mutation in this exon resulting in a single amino acid change (Ala354Asp). It is likely that this point mutation gives rise to the D(II) phenotype. Both mutations result in the change to Rh D-specific residues. Our results indicate that the following amino acids are crucial for epD3a (Asp350), epD3b (Asp350 + Gly353), epD4a (Gly353 + Ala354), epD4b (Ala354), epD9a (Asp350 + Gly353 + Ala354) and epD9b (Asp350 + Ala354) expression. All of these amino acids reside on the predicted sixth external domain of the Rh D protein, so it is possible that epD3, 4 and 9 are continuous epitopes.

Amino Acids↗
PubMed1997

Nitric oxide production in burns: plasma nitrate levels are not increased in patients with minor thermal injuries.

BACKGROUND: Recent studies have suggested that adults who sustain burns of less than 15% total body surface area display elevated plasma nitrate levels, indicating increased production of nitric oxide. The present study was initiated to confirm whether plasma nitrate is elevated in minor burn injury and, if so, whether it heralds the onset of a systemic inflammatory response to that injury. METHODS: Plasma samples were taken from 98 control and 10 burns patients. RESULTS: The mean plasma nitrate level for nine burns patients with a mean total body surface area burnt of 7.65% (range, 4-15%) was 42.83 micromol/L on day 1. This was not significantly different from that of a control population of 98 preoperative plastic surgery patients: 36.91 micromol/L (p = 0.162). Eight of 10 burns patients showed a decrease in plasma nitrate to 27.47 micromol/L by day 3 (p = 0.046). Elevated nitrate levels were seen in 2 of 10 burns patients. One had concurrent smoke-inhalation injury preceding multiple organ dysfunction, and one was treated with a cream containing cerium nitrate (Flammacerium, Duphar Laboratories, Southhampton, United Kingdom). CONCLUSIONS: For patients who sustain minor burns, plasma levels of nitrate decrease from those of mean normal controls with time unless there is multiple organ dysfunction or the patient receives extraneous nitrate.

Adult↗
PubMed1997

Retroviral marking identifies grafted autologous keratinocytes in porcine wounds receiving cultured epithelium.

Cultured epithelial autografts are often applied to wounds with a capacity for regeneration from dermal appendages. It is unclear in these circumstances whether the cultured autografts act merely as a biologic dressing or whether they become incorporated into the new epithelium. We have used retroviral gene transfer techniques to identify autologous keratinocytes in an established porcine model of cultured epidermal (CE) grafting. Porcine keratinocytes were transduced with an MFG-lacZ nls vector produced by the amphotropic packaging line GP+EnvAm12. Transduction rates of 15.1%, in the absence of selection, were achieved by a single passage on gamma-irradiated retroviral producers as a feeder layer. Full-thickness wounds were created on Large White pigs and isolated from the surrounding skin by a polytetrafluoroethylene chamber. Wounds were grafted initially with autologous de-epidermized dermis (DED), followed 7 d later by sheets of retrovirally marked or unmarked CE autografts. Two weeks after grafting, the mean area of epithelium was 48.4% in wounds that received CE grafts and 32.3% in wounds that were left as DED alone. The epithelium on DED represents regeneration from dermal appendages. The contribution made by the autograft cells to the new epidermis was demonstrated unequivocally, however, by lacZ-positive areas visible macroscopically on the surface of the excised wound. In cryostat sections through the lacZ-positive areas, retrovirally marked cells were present at both superficial and basal positions in the new epithelium.

Animals↗
PubMed1997

Exclusion probabilities of 22 bovine microsatellite markers in fluorescent multiplexes for semiautomated parentage testing.

Six multiplexes developed for semiautomated fluorescence genotyping were evaluated for parentage testing. These multiplexes contained primer pairs for the amplification of 22 microsatellites on 17 bovine autosomes. Exclusion probabilities were determined from genotypes of 1022 Holstein cattle and 311 beef cattle belonging to five breeds. Two cases were considered: case 1, genotypes are known for an alleged parent and an offspring but genotypes of a confirmed parent are unknown; and case 2, genotypes are known for an alleged parent, a confirmed parent and an offspring. If the alleged parent is not the true parent, then the 22 markers will exclude the alleged parent with a probability of > 0.9986 for case 1 and with a probability of > 0.99999 for case 2. On the basis of these exclusion probabilities, the probability that an alleged parent will be falsely included as a parent is in the range of 1/716 to 1/2845 for case 1 and 1/1.2 million to 1/159753 for case 2. In addition to these results, a rapid and efficient non-organic method for extraction of DNA from semen is described.

Animals↗
PubMed1997

A case of hyperzincemia with functional zinc depletion: a new disorder?

We report the case of an 1l-y-old boy with a plasma Zn concentration greater than 200 micromol/L, but with symptoms consistent with Zn deficiency. He has had hepatosplenomegaly, rashes, stunted growth (<3rd centile), anemia, and impaired immune function since infancy. He also has vasculitis and osteoporosis. A plasma Zn-binding protein has been separated and characterized by a combination of size exclusion and ion exchange chromatography and electrophoretic studies and by immunologic methods. Antibodies to the partially purified protein have been raised in rabbits. Size exclusion chromatography shows that Zn is bound to a protein with a mass 110000-300000 kD. Electrophoretic and mass spectrometry studies suggest that the protein may be composed of several subunits. One component of the isolated protein reacts with antiserum to alpha2-macroglobulin; immunoprecipitation studies confirm that the protein is not alpha2-macroglobulin or a histidine-rich glycoprotein. Kinetic studies of zinc metabolism in the patient and his mother with stable Zn isotopes show the presence of increased exchangeable Zn, with a rapid flux from plasma to a stable pool. Liver and muscle Zn and Cu concentrations are raised, but with no abnormal liver histology. Immunoreactive metallothionein in the liver is increased. We suggest that this boy may suffer from a previously unrecognized inborn error of Zn metabolism causing symptomatic zinc deficiency.

Biopsy↗
PubMed1997

Speed, sex, gay men, and HIV: ecological and community perspectives.

Fifteen years into the HIV/AIDS epidemic, a great deal is now known about the different populations impacted by the disease, including those affected directly or indirectly by drug use. Anthropology has played a critical role in assisting with this task by identifying hidden populations, developing new methodological approaches, and targeting outreach efforts. In spite of this considerable body of ethnographic knowledge, men who have sex with other men (i.e., MSM, or gay and bisexual men) who use drugs have not received the same research attention as other drug users, despite the fact that they represent nearly one-fifth of AIDS cases in the U.S. with injection drug histories. In response to the alarming increase in HIV seroprevalence among this population, this ethnographic project provides preliminary data about those who are at dual risk for HIV through both homosexual behavior and injection drug use.

Adult↗
PubMed1997

Gap junction channels: new roles in disease.

The importance of intercellular communication to complex cellular processes such as development, differentiation, growth, propagation of electrical impulses and diffusional feeding has long been appreciated. The realization that intercellular communication is mediated by gap junction channels, which are in turn comprised of a diverse family of proteins called the connexins, has provided new tools and avenues for studying the role of intercellular communication in these important cellular processes. The identification of different connexin isoforms has not only enabled the development of specific reagents to study connexin expression patterns, but has also allowed the functional properties of the different connexin isoforms and how they interact with each other, to be explored. Increasingly, the knowledge gained from studying connexin diversity is being used to investigate the role played by gap junction channels in a number of diseases. In this article we highlight selected cases where gap junction channels have been shown or are believed to be directly involved in the disease process.

Animals↗
PubMed1996

Effects of a multidimensional anabolic steroid prevention intervention. The Adolescents Training and Learning to Avoid Steroids (ATLAS) Program.

OBJECTIVE: To test a team-based, educational intervention designed to reduce adolescent athletes' intent to use anabolic androgenic steroids (AAS). DESIGN: Randomized prospective trial. SETTING: Thirty-one high school football teams in the Portland, Ore, area. PARTICIPANTS: Seven hundred two adolescent football players at experimental schools; 804 players at control schools. INTERVENTION: Seven weekly, 50-minute class sessions were delivered by coaches and student team leaders, addressing AAS effects, sports nutrition and strength-training alternatives to AAS use, drug refusal role play, and anti-AAS media messages. Seven weight-room sessions were taught by research staff. Parents received written information and were invited to a discussion session. MAIN OUTCOME MEASURES: Questionnaires before and after intervention and at 9- or 12-month follow-up, assessing AAS use risk factors, knowledge and attitudes concerning AAS, sports nutrition and exercise knowledge and behaviors, and intentions to use AAS. RESULTS: Compared with controls, experimental subjects at the long-term follow-up had increased understanding of AAS effects, greater belief in personal vulnerability to the adverse consequences of AAS, improved drug refusal skills, less belief in AAS-promoting media messages, increased belief in the team as an information source, improved perception of athletic abilities and strength-training self-efficacy, improved nutrition and exercise behaviors, and reduced intentions to use AAS. Many other beneficial program effects remained significant at the long-term follow-up. CONCLUSIONS: This AAS prevention program enhanced healthy behaviors, reduced factors that encourage AAS use, and lowered intent to use AAS. These changes were sustained over the period of 1 year. Team-based interventions appear to be an effective approach to improve adolescent behaviors and reduce drug use risk factors.

Adolescent↗
PubMed1996

Incidence and clinical relevance of the occurrence of bundle-branch block in patients treated with thrombolytic therapy.

BACKGROUND: Whether thrombolytic therapy alters the incidence and clinical outcome of bundle-branch block is unclear. METHODS AND RESULTS: We examined the occurrence of new-onset bundle-branch block, both transient and persistent, in 681 patients with acute myocardial infarction enrolled in the Thrombolysis and Angioplasty in Myocardial Infarction 9 and Global Utilization of Streptokinase and t-PA for Occluded Arteries 1 protocols. Each patient underwent continuous 12-lead ECG monitoring for 36 to 72 hours with the Mortara ST monitoring system. Bundle-branch block was characterized as right, left, alternating, transient, or persistent. The overall incidence of bundle-branch block was 23.6% (n = 161), with transient block in 18.4% (n = 125) and persistent block in 5.3% (n = 36). Right bundle-branch block was found in 13% (n = 89) of the population; left bundle-branch block was found in 7% (n = 48). Alternating bundle-branch block was seen in 3.5% (n = 24) of patients. Left anterior descending artery infarcts accounted for most bundles (54%, n = 79). Patients with bundle-branch block had lower ejection fractions, higher peak creatine phosphokinase levels (P < .0001), and more diseased vessels (P < .019). Mortality rates in patients with and without bundle-branch block were 8.7% and 3.5%, respectively (P < .007). A higher mortality rate was observed in the presence of persistent (19.4%) versus transient (5.6%) or no (3.5%) bundle-branch block (P < .001). CONCLUSIONS: Thrombolytic therapy reduces the overall mortality rate associated with persistent bundle-branch block. However, persistent bundle-branch block remains predictive of a higher mortality rate than either transient or no bundle-branch block. Continuous 12-lead ECG monitoring provides an accurate characterization of the incidence and type of conduction disturbances after acute myocardial infarction.

Aged↗
PubMed1996

Physicians' documentation of sexual abuse of children.

OBJECTIVES: To assess the quality of documentation by physicians in their evaluations for sexual abuse of children and to define factors that affect documentation. DESIGN: Cross-sectional survey and blinded chart review. SETTING: A statewide program for child abuse evaluations. PARTICIPANTS: Physicians (n = 145) who performed evaluations during fiscal year 1992-1993 were surveyed. Up to five randomly chosen medical records (n = 548), obtained from each eligible physician, were reviewed. INTERVENTIONS: None. MEASUREMENTS AND RESULTS: A survey of physicians who participated in the statewide program was made in summer 1993, with 78% participation. Knowledge scores were derived from the survey based on a comparison with the responses of a panel of five experts. Charts that were obtained from eligible physicians were assessed by two blinded reviewers. Documentation of the history and physical examination was evaluated as good or excellent by 30% and 23% of the physicians, respectively. Factors that were positively associated with better documentation of the history included a more structured format for the record, continuing medical education courses on sexual abuse of children, female gender, and a history of disclosure (P < .005 for all). Factors that were related to good documentation of the physical examination included structured records, continuing medical education courses, female gender, and knowledge scores. Factors that were not related to knowledge or documentation included the number of evaluations performed, practice group size or location, age of the physician, and a physician's reading of journal articles about sexual abuse of children. CONCLUSION: Quality of evaluations for sexual abuse of children may be improved by the use of structured records and participation in continuing medical education courses with regard to sexual abuse of children.

Adult↗