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A M Downs

Publications and source records attributed to A M Downs.

66 records · Page 4Linked to original sources
PubMed1990

Surveillance of AIDS in the European Community: recent trends and predictions to 1991.

Statistical modelling is applied to routine AIDS surveillance data to assess recent trends and to provide a range of short-term predictions. Several alternative functions have been fitted to half-yearly incidence data reported by the countries of the European Community by 31 December 1989 and adjusted for reporting delays. Among homosexual/bisexual men, recent trends in AIDS incidence are more nearly linear than exponential. Higher though less than exponential rates of growth are observed among intravenous drug users and among those presumed infected by heterosexual contact. Extrapolations to the end of 1991 using each of five functions provide a range of forecasts. Projections of total cumulated cases to the end of 1991 lie in the range 60,000-78,000, with 24,000-30,000 projected cases among homosexual/bisexual men, 23,000-33,000 among intravenous drug users, and 6000-8000 in the heterosexual transmission group. With the possible exception of the latter group, the lower parts of these ranges appear more probable.

Acquired Immunodeficiency Syndrome↗
PubMed1989

Correcting reported AIDS incidence: a statistical approach.

This study is motivated by the time lag between date of diagnosis of AIDS cases and date of reporting, which results in incomplete data about the epidemic. A maximum likelihood procedure has been developed to adjust the actual numbers of diagnosed AIDS cases for reporting delay. If a parametric function for describing past and future incidence is assumed, its parameters and the adjustment for reporting delay can be estimated simultaneously. Data from the WHO Collaborating Centre on AIDS, Paris, are used. Practical problems related to data collection are dealt with.

Acquired Immunodeficiency Syndrome↗
PubMed1987

AIDS in Europe: current trends and short-term predictions estimated from surveillance data, January 1981-June 1986.

European AIDS surveillance data, reported to the World Health Organization (WHO) Collaborating Centre on AIDS, Paris by 30 June 1986, have been analysed statistically to assess current trends and to provide short-term predictions. Reported case numbers were first adjusted to allow for the estimated time delays between diagnosis and reporting. The adjusted data (cases per half-year of diagnosis) were then fitted using exponential functions over selected time intervals to monitor and compare the evolution of the epidemic in individual countries and in the European Community (EC) as a whole. Predictions to mid-1988 were made by extrapolation. Results are presented for the EC and for the following individual countries: Belgium, Denmark, France, Federal Republic of Germany, Italy, The Netherlands, Spain, Sweden, Switzerland and the United Kingdom.

Acquired Immunodeficiency Syndrome↗
PubMed1984

An improved approach to the analysis of autoradiographs containing isolated sources of simple shape: method, theoretical basis and reference data.

There are circumstances in which, by assuming that a high proportion of the radioactivity in a biological specimen is associated with certain well-dispersed structures of simple shape, a relatively simple and effective objective analysis can be carried out. The usefulness of this type of restricted analysis has previously been severely limited by the requirement that all the profiles of interest should be of roughly the same size, which is rarely the case. A procedure is proposed which, by appropriately combining image spread functions for profiles of the same shape but of various sizes, allows realistic hypothesis testing in such circumstances. Details for the practical application of the method are offered and criteria for assessing the feasibility of applying the method in particular circumstances are discussed. The necessary backup information to the method is supplied in the form of the derivation of the fundamental image spread function, the introduction of a coherent notation and reference data quantitatively describing the image spread around certain extended sources of simple shape.

Animals↗
PubMedDate not supplied

WT1-targeted immunotherapy of leukaemia.

Since malignant cells are derived from normal cells, many tumour-associated antigens are also expressed in normal tissues. For examples, WT1 is expressed at elevated levels in most leukaemias, but it is also expressed at reduced levels in normal CD34+ haematopoietic stem cells and in progenitor cells of other tissues. Antigen expression in normal tissues is likely to trigger immunological tolerance and thus blunt T cell responses. This could explain the observation that WT1 vaccination in mice frequently fails to stimulate high avidity cytotoxic T cell responses. In order to circumvent tolerance, we have isolated from HLA-A2-negative donors high avidity CTL specific for HLA-A2-presented peptide epitopes of WT1. These allorestricted CTL efficiently kill HLA-A2-positive leukaemia cells but not normal CD34+ haematopoietic stem cells. However, adoptive cellular therapy with allorestricted CTL could only be performed in leukaemia patients rendered tolerant to the infused CTL by prior allogeneic stem cell transplantation. In order to circumvent this limitation, we propose to exploit the TCR of allorestricted CTL as therapeutic tool. TCR gene transfer can be used to take advantage of the specificity of allorestricted CTL and transfer it to patient CTL, while avoiding the transfer of immunogenic alloantigens from the donor CTL to the patient.

Animals↗
PubMedDate not supplied

Incubation time for AIDS.

Explore the source record for details and available documents.

Acquired Immunodeficiency Syndrome↗
PubMedDate not supplied

Scleroatrophic syndrome of Huriez in an infant.

We present a 3-year-old boy with scleroatrophic syndrome of Huriez, a rare autosomal dominant condition with only seven affected families worldwide. Although assumed to occur from birth, an evolving case has not previously been documented. Infants do not possess the focal areas of keratoderma on the palms or soles; these develop in adult life. Of particular interest is the high incidence of squamous cell carcinomas that arise from the scleroatrophic skin.

Adult↗
PubMedDate not supplied

Eruptive collagenomas of the skin: a case history.

We present a case of eruptive collagenomas of the skin in a young girl. The typical clinical features and histology of this rare condition are described. The differential diagnosis and other types of cutaneous collagenomas are briefly discussed. A biopsy is required to confirm the excessive mature collagen which predominates in these lesions.

Biopsy↗
PubMedDate not supplied

Use of the allogeneic TCR repertoire to enhance anti-tumor immunity.

It is well established that antigen-specific T lymphocytes can inhibit tumor growth in humans and in mice, leading to complete tumor elimination in some cases. However, in many cases T cell immunity is unable to successfully control tumor progression. Since tumors are derived from normal tissues, most antigens are shared with normal tissues, although expression levels are usually elevated in malignant cells. Nevertheless, low-level expression in normal cells can be sufficient to render autologous T cells tolerant and thus unable to mount effective immune responses against tumors. Here, we review how allogeneic T cells can be used to isolate T cells that effectively recognise and kill tumor cells, but not normal cells with low level of antigen expression. The TCR of allogeneic T cells can be introduced into patient T cells to equip them with anti-tumor specificity that may not be present in the autologous T cell repertoire.

Graft vs Host Disease↗