Risk contexts and risk behaviors in the Euregion Maas-Rhein: the Boule de Neige intervention for AIDS prevention among drug users

Using targeted sampling, self-reported data of 1,767 drug users in the Euregion Maas-Rhein were collected over 3 years. Forty-two percent of the injection drug users shared syringes with sexual partners and 47.8% with friends. Eighty-one percent of the total sample had sexual contact in the last 6 months, half of whom with one person and half with two or more. Significant predictors of high-risk drug use were injecting in the presence of others, injection onset before the age of 20, female gender, and not living in The Netherlands. Participation in needle exchange or methadone programs and sufficient knowledge of risk factors was not significantly related to a reduction of high-risk drug use behavior. High-risk sexual behavior was found to be related to male gender, under the age of 30 and to multiple sexual partners. We conclude that in a social context where needle exchange, methadone programs, and sufficient knowledge of risk factors among the drug user population exist, AIDS prevention can be improved through behavioral skills training and developing specific interventions that target the peer group environments, rituals, partner relationships, and lifestyles of drug users.     

Epidemiological characteristics of bovine herpesvirus 1 infections determined by bulk milk testing of all Dutch dairy herds

Samples of bulk milk were taken from all 33,636 Dutch dairy herds in November 1994 and tested for the presence of bovine herpesvirus 1 (BHV-1) antibodies with a gB-blocking ELISA. Sixteen per cent of the herds had a negative BHV-1 status in the bulk milk. Farms with only dairy cows were 1.9 times more likely to have a negative or weakly positive BHV-1 status than herds which also had beef/veal animals. Farms in areas containing less than one herd/km2 were 1.5 times more likely to have a negative or weakly positive BHV-1 status than herds in areas with more than three herds/km2. Differences in numbers of animals per unit area were not significantly associated with BHV-1 status. The probability of herds having a negative or weakly positive BHV-1 status decreased linearly with herd size by a factor of 1.2 per 10 animals. The purchase of stock was significantly associated with a negative or weakly positive BHV-1 status, but there was an interaction between farm type and purchase of stock. For farms with both dairy and beef/veal animals there was a weak association between the purchase of stock and BHV-1 status. For pure dairy herds the probability of having a negative or weakly positive BHV-1 status decreased linearly with the numbers of purchased stock by a factor of 1.3 per 10 animals purchased.     

Arteriography of sacrococcygeal teratomas

Sacrococcygeal teratomas often present at birth as skin-covered caudal masses. Because of the variable intrapelvic and presacral extension of these tumors, high mortality from hemorrhage, variable blood supply, and occasional confusion with other caudal masses, preoperative arteriography is useful. The arteriographic findings in 4 neonates with sacrococcygeal teratoma are presented.     

The performability manager

The authors describe the performability manager, a distributed system component that contributes to a more effective and efficient use of system components and prevents quality of service (QoS) degradation. The performability manager dynamically reconfigures distributed systems whenever needed, to recover from failures and to permit the system to evolve over time and include new functionality. Large systems require dynamic reconfiguration to support dynamic change without shutting down the complete system. A distributed system monitor is needed to verify QoS. Monitoring a distributed system is difficult because of synchronization problems and minor differences in clock speeds. The authors describe the functionality and the operation of the performability manager (both informally and formally). Throughout the paper they illustrate the approach by an example distributed application: an ANSAware-based number translation service (NTS), from the intelligent networks (IN) area     

Two complementary approaches to study peroxisome biogenesis in Saccharomyces cerevisiae: forward and reversed genetics

In order to investigate the mechanisms of peroxisome biogenesis and to identify components of the peroxisomal import machinery we studied these processes in the yeast Saccharomyces cerevisiae. The forward genetic approach has led to pas-mutants (peroxisomal assembly) which fall into 12 complementation groups and allowed to identify 10 of the corresponding wild-type PAS genes (PAS 1-7, 9, 11 and 12). Recent sequence analysis data of some of these genes are beginning to provide first hints as to the possible function of their gene products. The PAS genes and their corresponding mutants are presently used to address some important questions of peroxisomal biogenesis. Reversed genetics has been started as a complementary approach to characterize especially the function of peroxisomal membrane proteins. For this purpose we describe a technique to isolate highly purified peroxisomes. This led to the identification of 21 polypeptides as constituents of this organelle. Some of them are presently sequenced.     

Congenital dysplasia of C2--6

The gastric secretion of 99mTc-pertechnetate as a means of assessing parietal cell function was investigated in 12 pernicious anemia (PA) patients with histamine-fast achlorhydria. Twelve control subjects were either normal volunteers or patients proven not to have either PA or any other gastrointestinal disease. The results indicated that, while the stomachs of PA patients secreted no hydrochloric acid, they continued to secrete 99mTc-pertechnetate, indicating that 99mTcO4 - is secreted not by parietal cells alone or else not by parietal cells at all. The gastric pertechnetate activity, therefore, cannot be used as an index of gastric acid secretory activity in PA.     

Charakterisierung der Phosphorylase aus Kartoffeln durch Ultrazentrifuge und Gelpermeationschromatographie

Characterization of Potato Phosphorylase by Ultracentrifugation and Gel Permeation Chromatography. Potato phosphorylase was characterized by ultracentrifugation and gel permeation chromatography. The sedimentation constant was determined by sedimentation transport measurements at protein concentrations of 2 to 20 mg/ml. Using the equation of Scholtan the molecular weight of phosphorylase was found to be 200 000. The same value was obtained by gel permeation chromatography. In all experiments the phosphorylase behaved as a homogeneous component, whereas the measurements of sedimentation equilibrium showed a concentration dependence of the molecular weight indicating dissoziation of the phosphorylase protein into two components with a molecular weight of each 90 000. As the dissoziation of the phosphorylase into two subunits didn't bring about either an inactivation or a change of the specific activity the existence of an enzymatically active protein with a molecular weight of 90 000 is to be assumed.