PURPOSE: mdplot (medical database plot) visualizes both structure and quality of data in medical databases by means of a summary representation of design and completeness in XML format. The goal is to identify attributes suitable for evaluation and to aid in creating open data models. METHODS: A three-stage visualization approach is applied. First, an overview of all classes in a database, second a detailed view of a specific class and third an analysis of individual attributes. Missing data is identified to enable specific efforts to improve data quality prior to analysis. For each class number of patients, attributes, and records per patient are provided. A condensed bar chart for each category of attributes (categorical, numerical, text and other) visualizes available content: The abscissa corresponds to the sequence of attributes; the ordinate represents completeness per attribute. By selection of a specific class, a detailed description is provided including mean completeness in each category as well as completeness per attribute. To analyse attributes that are collected at several time points per patient, a frequency distribution of records per patient can be generated. RESULTS: The new methodology was applied to two clinical research databases consisting of 292 attributes (955 patients) and 224 attributes (610 patients), respectively, and resulted in major restructuring of the systems. A public website is provided for generation of mdplots.

Data Collection↗

PubMedDate not supplied

An anti-HIV strategy combining chemotherapy and therapeutic vaccination.

Combination chemotherapy using potent anti-retroviral agents has led to significant advances in the clinical management of human immunodeficiency virus (HIV) disease. However, the emergence of multiple drug-resistant mutants, the high need for compliance to adhere to demanding drug-dosing schemes, and the remaining toxic side-effects of drugs make the perspective of life-long treatment unattractive and possibly unrealistic. Therefore, means must be sought to shorten the time span during which treatment is necessary. Such means could be to stimulate an efficient immune response during the period of low virus load and restored CD4 + cell levels, which might be capable of keeping the virus under long-lasting control after treatment is stopped. Here we tested this concept of combined chemotherapy/ therapeutic vaccination in a non-human primate model. Rhesus macaques chronically infected with the chimeric simian/human immunodeficiency virus (SHIV) containing the HIV type 1 (HIV-1) HXBc2 gene for reverse transcriptase (RT) in the genomic background of simian immunodeficiency virus (SIV)(mac239) (RT-SHIV) were treated with (R)-9-(2-phosphonylmethoxypropyl)adenine (PMPA), a potent anti-HIV drug. When virus load had decreased significantly, we immunized with SIV genes env, gag/pol, rev, tat, and nef inserted in two different expression vector systems. Four weeks after the second immunization, drug treatment was stopped. Animals were monitored to determine if virus load stayed low or if it increased again to the original levels and if CD4+ T-cell levels remained stable. Humoral and cellular immune responses were also measured. This combined chemotherapy/ therapeutic vaccination regimen induced a significant reduction in the steady-state level of viremia in one out of two chronically infected rhesus macaques. Chemotherapeutic treatment alone did not achieve reduction of viremia in two chronically infected animals. The nature of the immune responses assumed to have been induced by vaccination in one out of the two monkeys remains to be elucidated.

AIDS Vaccines↗

PubMedDate not supplied

Spontaneous platelet aggregation and coagulation parameters as risk factors for arterial occlusions in diabetics. Results of the PARD-study.

PARD is a prospective study sponsored by the German Research Council with the aim to establish whether spontaneously enhanced platelet aggregation or changes of other hemostatic parameters are risk factors for new vascular occlusions in diabetic patients. 363 diabetic patients (aged 45-65, 232 men, 131 women) were observed for 5 years. Of the 232 men, 53 were on diet, 104 on oral antidiabetic drugs and 75 on insulin. Of 131 women 16 were on diet, 46 on oral antidiabetic drugs and 69 on insulin. At entry clinical examination and laboratory tests were performed, covering the known risk factors for cardiovascular complications. Hemostatic tests and clinical examination were performed at 3 months' intervals. The life status was followed for all patients. Endpoints were carefully defined. Until December 31, 1984, 42 patients died, 23 from cardiovascular disease and 19 from other causes. 13 patients suffered a myocardial infarction, 10 a stroke and 53 peripheral arterial occlusions. The occurrence of new vascular occlusions was significantly higher in those men with enhanced spontaneous platelet aggregation measured by PAT III angle alpha above 40 degrees at entry as compared to those with lower values. This was not the case for women. Other hemostatic parameters, which had also some relation to cardiovascular complications, in men were fibrinogen and F. VIII R:Ag. Established risk factors for which a significant relation to cardiovascular complications was observed in this study, were smoking, duration of diabetes, diastolic blood pressure, cholesterol, triglycerides and also HbA1. The results of the PARD-study have verified the hypothesis that spontaneous aggregation is a major risk factor for future vascular occlusions in diabetic men. They also lead to the hypothesis that high levels of F. VIII R:Ag and fibrinogen are further indicators of progressive vascular disease and may be useful as predictors of new vascular occlusions in combination with such established risk factors as smoking, duration of diabetes, diastolic blood pressure, cholesterol, and triglycerides.

Aged↗