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D Wright

Publications and source records attributed to D Wright.

At least 109 records · Page 6Linked to original sources
PubMed1998

Telemedicine and developing countries. A report of study group 2 of the ITU Development Sector.

While there are significant potential advantages and benefits from telemedicine, the evidence of its cost-effectiveness and sustainability is meagre. This is because much of the telemedicine activity so far has been in the form of pilot projects of demonstrations in universities and hospitals with subsidized funding from government or other sources. The number of self-sustaining, commercial applications of telemedicine is still very small. Telemedicine undoubtedly yields cost savings in certain circumstances, but often the savings and benefits accrue to those who do not have to pay for the service. Thus, few service providers have found a way to recover their costs (and make a profit) from those to whom they provide their service. Even fewer countries have actually budgeted for the provision of telemedicine as a service widely available to their citizens. Nevertheless, with the rapidly declining cost in hardware and telecommunications, the level of interest and the corresponding activity in telemedicine is rising rapidly. Most of the telemedicine experience to date has been in the industrialized world. It is apparent that the first requirement of developing countries is for more information about telemedicine, what it is, and how it might be able to help solve some of the shortages in medical and health care. Given the potential of telemedicine to facilitate the provision of medical information and health care in rural areas, it seems useful for developing countries to undertake pilot projects in order to evaluate its potential and cost-benefits. The results of such pilot projects could be part of the development of a national health for all policy which takes telemedicine into account. In view of the other priorities of developing countries, especially those of the least developed countries, financing telemedicine activity is likely to remain a challenge for some time to come. Funding from external donor agencies may well be necessary, but local commitment and participation in pilot projects is essential if the project is to have a chance of success. As telemedicine requires a multidisciplinary approach, the active participation of telecommunication operators must be assured. Despite some false starts in the deployment of telemedicine as a continuing service to the general population--as opposed to a few well-to-do clients--telemedicine has great potential to improve access to health care and to contain costs in developing countries.

Computer Communication Networks↗
PubMed1997

Prevalence of youth substance use: the impact of methodological differences between two national surveys.

This study compared two major Federally sponsored surveys of adolescent substance use and assessed the impact that methodological differences have on the prevalence estimates they generate. The Monitoring the Future Survey, a school-based survey, was compared to the National Household Survey on Drug Abuse, a household survey of the population aged 12 years and older. Response rates were higher in the household survey due to high rates of refusal in the school based survey. The school survey has a larger overall sample size, but sampling errors more similar than one might expect, because of the larger design effects in the school survey. Rates of drug use obtained were larger in the school survey than in the household survey, possibly because of greater under-reporting in the household setting than in the classroom and the different questionnaires used in the two surveys.

Adolescent↗
PubMed1997

The effect of hormone replacement therapy of the age-related rise of factor VIIc, and its activity state.

Although hormone replacement therapy (HRT) appears to protect women from ischaemic heart disease (IHD), its use is associated with increased factor clotting activity (VIIc), an independent risk factor for IHD. The nature of this factor VII rise was therefore examined in a cross-sectional study of 279 women aged between 40 and 65 years. Ninety-four were pre-menopausal, 44 were post-menopausal and taking HRT, whilst 141 were post-menopausal non-users. For those women on oestrogen-only HRT, the mean factor VIIc was 144%, compared to 130% for post-menopausal non-users, and 116% for those on combined HRT. These differences were significant (p = 0.01). Oestrogen-only users also had significantly higher mean levels of factor VIIa (3.3 ng/ml) compared to non-users (2.2 ng/ml) and those on oestrogen-progestogen HRT (2.2 ng/ml-p = 0.015). In contrast for factor VII antigen the mean values of the three groups were similar. Analysis of the age-regression slopes showed a significant age-related rise in factor VIIc of 1.2% per annum (p < 0.01) for post-menopausal non-users. There was a similar increase in factor VII antigen (2.1%) but no rise in factor VIIa. For all HRT users there was no change with age for any of the factor VII measures. Thus the age-related rise in factor VIIc appears to be due to an increase in factor VII zymogen alone, and taking HRT seems to abolish such a rise. In contrast, the increased factor VIIc seen with oestrogen-only HRT appears to be secondary to factor VII activation.

Adult↗
PubMed1997

Modelling and simulation of the hand grasping using neural networks.

In this paper we present preliminary results of a study on the use of artificial neural networks to model and simulate the hand grasping. Results of this study will provide a basic understanding of the co-ordination and control of multiple degrees of freedom upper limb prosthetic devices and robotic end effectors when interacting with the environment. We assumed the hand to be a black box with the inputs being the object and simulation time sequence, whilst the output is the grasping postures over time. We trained the network with samples of key postures of the hand grasping several object shapes and sizes. The back-propagation technique was used to update the weights of the network. We found that the neural network is able to reproduce the postures of the hand grasping objects of different shapes and sizes from a single set of neural network weights.

Computer Simulation↗
PubMed1997

Getting out of the asylum: understanding the confinement of the insane in the nineteenth century.

This paper critically re-examines our assumptions about the social rule of asylums in the nineteenth century by separating the history of the confinement from the history of psychiatry. Rather than medical superintendents being central to the admission of patients, this paper will argue that control over confinement was predicated upon the desires of families to care for and control dependent and violent relatives. The confinement of the insane can thus be seen not as a consequence of a professionalizing psychiatric elite, but rather as a strategic response of households to the stresses of industrialization. The second part of this paper surveys changing approaches to the social history of the asylum and directs these techniques to a combination of institutional and non-institutional sources which will shed new light on the dynamic between informal patterns of family caring 'in the community' and formal medical treatment in purpose-built institutions. Having set out the methodological possibilities of using new types of admission records, the last section of this paper explores different approaches to the history of the family and applies them to the question of why the insane were confined. This will provide an analytical framework for understanding the interface between the family and the formal medical institution. Throughout, this paper draws on more than three dozen international studies to illuminate some comparative aspects of confinement in different national contexts.

Family Health↗
PubMed1997

Creating a healthy work environment in the midst of organizational change and transition.

In the midst of organizational change and transition, the need for a healthy work environment is greater than ever. Leaders may be in a position of leading staff on a journey they would rather not be on. Although there may not be a choice of destination, there are many decisions to be made along the way that will impact the health and quality of the journey. Creation of a healthy work environment does not occur overnight. It requires acknowledgment of the reality of the present environment, clear behavioral expectations and standards, systems, and structures to ensure the organizational changes are enduring and a means to assess continually the health of the work environment. Leaders have an opportunity and a responsibility to structure organizations in such a way that dignity, integrity, honesty, and compassion are preserved.

Hospitals, University↗
PubMed1997

Illness severity measured by CRIB score: a product of changes in perinatal care?

AIM: To determine the perinatal factors associated with initial illness severity (measured by the CRIB (clinical risk index for babies) score) and its relation to survival to discharge. METHODS: A retrospective study was made of intensive care nursing records on 380 inborn babies, of less than 31 weeks gestation or 1501 g birthweight, admitted to one unit between 1984-6 and 1991-4. RESULTS: Between the two time periods mean initial illness severity score increased significantly from 2.8 to 3.9. This was the result of an increase in the maximum appropriate inspired oxygen concentration in the first 12 hours. Risk adjusted survival did not improve over time after accounting for gestation but was significantly greater after accounting for CRIB score. Illness severity score was also significantly inversely associated with gestation and 1 and 5 minute Apgar scores, using multiple regression analysis. Between the two time periods there was also a 92% increase in the admission rate of babies under 31 weeks gestation, higher median 1 and 5 minute Apgar scores (6 vs 5 and 9 vs 8, respectively), more multiple births, and more caesarean section deliveries. CONCLUSIONS: The increase in illness severity score and admission rate may reflect changes in obstetric practice. The increase in illness severity score may also reflect changes in early neonatal care. However, after adjusting for CRIB score, risk adjusted mortality fell significantly, suggesting that neonatal care 12 hours from birth onwards had improved with time.

Apgar Score↗
PubMed1997

Childhood non-Hodgkin lymphomas in the United Kingdom: findings from the UK Children's Cancer Study Group.

AIM: To review the presenting clinical features and the histology of cases of non-Hodgkin lymphoma (NHL) entered into the United Kingdom Children's Cancer Study Group NHL Trial. METHODS: Sections of biopsy specimens from all cases entered into the trial were stained with Giemsa and haematoxylin and eosin. All cases were stained immunohistochemically for CD45, CD3, CD45RO, CD20, and CD30. Sections were stained with either naphthol AS-D chloroacetate esterase or KP1 (CD68) to identify granulocytic tumours. In a minority of cases, additional immunohistochemical stains were performed when necessary to establish the diagnosis. The sections were reviewed by three pathologists. RESULTS: Of 308 cases analysed, 293 were categorised as NHL. There was only one case of low grade lymphoma in the series. Over 80% of the cases fell into the categories Burkitt lymphoma (42.2%), lymphoblastic lymphoma (27.2%) and anaplastic large cell lymphoma (15.1%). Cases of Burkitt lymphoma presented most often with abdominal tumours mainly of the ileocaecal region. Tumours of the oropharynx and nasopharynx were also common in this group. Of the 84 lymphoblastic lymphomas, 56 were of the T-cell phenotype, 12 of the B-cell phenotype and 16 of indeterminate lineage. Most of the T-lymphoblastic lymphomas showed mediastinal or pleural involvement. Infiltration of the skin and soft tissues was seen in 25% of lymphoblastic lymphoma of B or indeterminate phenotype. Forty six children were diagnosed as having anaplastic large cell lymphoma, the majority being of T or indeterminate lineage. Most patients presented with lymphadenopathy but involvement of the bones, soft tissues or skin was seen in seven patients and of the mediastinum and lungs in five. CONCLUSION: Childhood non-Hodgkin lymphomas are almost all high grade and frequently extranodal. They fall mainly into the categories Burkitt lymphoma, lymphoblastic lymphoma and anaplastic large cell lymphoma. The separation of these subcategories can be made on the basis of morphology and immunohistochemical features. The anatomical distribution of these different categories of non-Hodgkin lymphoma is distinctive.

Adolescent↗
PubMed1997

Does histology influence outcome in childhood Hodgkin's disease? Results from the United Kingdom Children's Cancer Study Group.

PURPOSE: Histology has been identified as an important prognostic factor in Hodgkin's disease (HD) in adults. Information regarding the impact of histology on outcome in childhood HD is scarce. This study determines the effect of histology on the overall survival (OS) or progression-free survival (PFS) in a national series of children treated in a standardized manner. PATIENTS AND METHODS: The results of treatment of 331 assessable patients, treated between January 1, 1982 and June 30, 1992, in the United Kingdom Children's Cancer Study Group (UKCCSG) Hodgkin's study I were reviewed to evaluate OS, PFS, and deaths according to stage and histology. Treatment was either involved-field radiation alone (stage IA) or chlorambucil, vinblastine, procarbazine, and prednisolone (ChlVPP) chemotherapy with or without mediastinal radiation. All were clinically staged at diagnosis. RESULTS: Nodular sclerosing (NS) HD was the most common histologic subtype (155 of 331 patients [47%]) and was uniformly distributed through all stages. Lymphocyte-depletion (LD) HD was extremely uncommon (< 1%). Mixed-cellularity (MC) HD had the highest relapse rate, but this was only significant (P < .05) in stage I patients who received local irradiation alone. There was no other statistically significant difference in OS and PFS between the various histologic subtypes. Multivariate analysis for PFS and OS confirmed that stage was the most important prognostic factor and that histology did not have an effect after stratification by stage. CONCLUSION: This study demonstrates that with effective multiagent chemotherapy, histologic subtype does not influence outcome. The high relapse rates in stage I MC subtype indicates that MC HD is biologically aggressive and systemic treatment with or without local irradiation may be indicated. The high relapse rate in stage IV patients appeared to be independent of histology.

Actuarial Analysis↗
PubMed1997

Telemedicine delivery to developing countries.

This paper highlights current activities with regard to telemedicine activities in and for developing countries. The paper reviews: the preparation of a telemedicine report by a study group of the International Telecommunication Union (ITU), the aim of which is to provide recommendations and guidelines for developing countries; the formation of the European Telemedicine Collaboration Group (ETCG), which is undertaking telemedicine pilot projects in developing countries; and telemedicine delivery via inmarsat, which is coordinating production of the ITU report and is a participant in the ETCG.

Developing Countries↗
PubMed1997

The prevalence and morbidity of chronic fatigue and chronic fatigue syndrome: a prospective primary care study.

OBJECTIVES: This study examined the prevalence and public health impact of chronic fatigue and chronic fatigue syndrome in primary care patients in England. METHODS: There were 2376 subjects, aged 18 through 45 years. Of 214 subjects who fulfilled criteria for chronic fatigue, 185 (86%) were interviewed in the case-control study. Measures included chronic fatigue, psychological morbidity, depression, anxiety, somatic symptoms, symptoms of chronic fatigue syndrome, functional impairment, and psychiatric disorder. RESULTS: The point prevalence of chronic fatigue was 11.3%, falling to 4.1% if comorbid psychological disorders were excluded. The point prevalence of chronic fatigue syndrome was 2.6%, falling to 0.5% if comorbid psychological disorders were excluded. Rates did not vary by social class. After adjustment for psychological disorder, being female was modestly associated with chronic fatigue. Functional impairment was profound and was associated with psychological disorder. CONCLUSIONS: Both chronic fatigue and chronic fatigue syndrome are common in primary care patients and represent a considerable public health burden. Selection bias may account for previous suggestions of a link with higher socioeconomic status.

Adolescent↗
PubMed1997

The use of external data sources and ratio estimation to improve estimates of hardcore drug use from the NHSDA.

Levels of hardcore drug use have been especially difficult to estimate because of the relative rarity of the behavior, the difficulty of locating hardcore drug users, and the tendency to underreport stigmatized behavior. This chapter presents a new application of ratio estimation, combining sample data from the National Household Survey on Drug Abuse (NHSDA) together with population counts of the number of persons arrested in the past year from the Uniform Crime Report (UCR) and the number of persons in drug treatment programs in the past year from the National Drug and Alcoholism Treatment Unit Survey (NDATUS). The population counts serve as a benchmark accounting for undercoverage and underreporting of hard drug users.

Cocaine↗
PubMed1997

Central nervous system opportunistic infections.

The spectrum of opportunistic infections occurring in association with human-immunodeficiency virus, type 1, is very broad. These infections develop most frequently in the setting of advanced immunosuppression. There is no part of the neuraxis that is immune to these complications and the concurrence of more than one infectious illness may always be considered. The neuroimaging features, when coupled with the clinical and laboratory findings, often suggest the correct diagnosis and enable the physician to initiate therapy.

AIDS-Related Opportunistic Infections↗
PubMed1997

A neural network approach to markerless measurement of human motion.

Most automatic motion analysis system operates by tracking markers across a field of view. The markers are usually attached to the skin at the joints. For some applications such as measuring the motion of elderly and the disabled persons, this approach can be uncomfortable which ultimately can affect the motion itself. The protocol of some markers can also be a problem for example active markers using infra-red LEDs must continuously be in the field of view of the detectors at all times. This will impose restriction in the motion. Therefore a marker free method is an attractive proposition. Such an approach would allow the subject to move freely thus exhibiting a more natural movement. We have developed a PC based system which uses frames from the video or photographic capture of a motion in the frontal and sagital plane. Key frames are selected and co-ordinate positions of the joints are identified. Joint angles are calculated from these positions based on a multiple link model of the human figure. The angles are then used as training data for a fully connected neural network. The neural network generates a model of the captured motion which is used to reproduce closely the actual motion.

Analog-Digital Conversion↗
PubMed1996

Male-to-female transmission of human T-cell lymphotropic virus types I and II: association with viral load. The Retrovirus Epidemiology Donor Study Group.

SUMMARY: Risk factors for male-to-female sexual transmission of human T-lymphotropic virus types I and II (HTLV-I/II) were investigated among HTLV-seropositive volunteer blood donors and their long-term (> or = 6 month) sex partners. Direction of transmission in concordantly seropositive pairs was assessed by analyzing risk factors for HTLV infection. Donors and their partners were also questioned regarding sexual behaviors during their relationships; HTLV antibody titers and viral load were determined for specimens from male partners. Among 31 couples in whom HTLV-infected men likely transmitted infection to their partners (11 HTLV-I and 20 HTLV-II) and 25 male-positive, female-negative couples (8 HTLV-I and 17 HTLV-II), HTLV transmitter men had been in their relationships longer (mean 225 months vs. 122 months) and had higher viral loads (geometric mean 257,549 vs. 2,945 copies/300,000 cells for HTLV-I; 5,541 vs. 118 copies/300,000 cells for HTLV-II) than non-transmitters (P = 0.018 and P = 0.001 for duration of relationship and viral load, respectively, logistic regression analysis). Transmitter men also tended to have higher antibody titers against various env and whole virus proteins than non-transmitters. The identification of high viral load and duration of relationship as risk factors provides a biologically plausible framework in which to assess risk of sexual transmission of the HTLVs.

Adult↗
PubMed1996

Changes in CD4+ and CD8+ cell levels during pregnancy and post partum in women seropositive and seronegative for human immunodeficiency virus-1.

OBJECTIVE: Our objective was to examine changes in CD4+ and CD8+ cell levels during pregnancy and post partum and to determine whether they differ for human immunodeficiency virus-1-seropositive and seronegative women. STUDY DESIGN: A total of 192 human immunodeficiency virus-1-seropositive and 148 seronegative women enrolled in a study of mother-to-child transmission of human immunodeficiency virus-1 who had at least two lymphocyte subset measurements performed during pregnancy or post partum were included in this analysis. Mixed effects repeated-measures models were developed to examine changes in CD4+ and CD8+ cell levels during this period. RESULTS: Consistent with prior reports that CD4+ cell levels decline during pregnancy and return to normal post partum, percent levels increased between the third trimester and 12 months post partum among human immunodeficiency virus-seronegative women (1.98%, p = 0.04). However, CD4+ levels declined steadily during pregnancy and post partum among seropositive women (-1.57%, p = 0.02 between the third trimester and 12 months post partum; =2.65%, p = 0.0004 between 2 and 24 months post partum). The percent CD8+ cell levels increased at or near delivery and declined to baseline between 2 and 6 months post partum in both seronegative and seropositive women, although only the declines were statistically significant in both groups (-2.66%, p = 0.004; and -2.02%, p = 0.02, respectively). CONCLUSIONS: The percent CD4+ cell levels declined steadily during pregnancy and post partum among human immunodeficiency virus-seropositive women, indicating that human immunodeficiency virus disease continues to progress during this period. The percent CD8+ cell levels increased at or near delivery and declined to baseline post partum in both seronegative and seropositive women. These findings may have important clinical implications for both human immunodeficiency virus-infected and uninfected pregnant women.

Adult↗