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The presence of HPV-DNA was determined in tumor biopsies of cervical-cancer patients and in cervical swabs of non-cancer patients from Tanzania, East Africa, by Southern blot hybridization and/or PCR. HPV types 16 and 18 were detected in 38% and 32%, respectively, of 50 cervical-carcinoma biopsies. A consensus primer PCR capable of detecting a broad spectrum of HPV types revealed the presence of HPV-DNA in 59% of 359 cervical swabs of non-cancer patients. Type-specific PCR showed that types 16 and 18 accounted for 13.2% and 17.5%, respectively, of all HPV infections. Therefore we concluded that HPV 18 is more prevalent in Tanzania than in any other geographical location so far reported. The strongest risk factors for the presence of any HPV-DNA in the 359 female non-cancer patients were young age and HIV infection. The epidemiology of HPV types 16 and 18 was found to differ from that of other HPV types, being associated in univariate analysis with trichomonas vaginalis infection, martial status (single/divorced), age at first intercourse, and young age at menarche. However, young age at menarche accounted for most of the effects of all other, variables in multivariate analysis. Of the non-cancer patients, 12.8% had antibodies against HIV I (no patient being severely symptomatic), and HIV infection was highly correlated with the presence of HPV-DNA, especially types 16 and 18. While HPV-DNA of any type was detectable 1.4-fold more often in HIV-positive patients than in HIV-negative patients, evidence of an infection with HPV types 16 or 18 was found 2.2-fold more often in the HIV-positive patients. The HIV-positive women did not show an increased rate of cervical cytological abnormalities as assessed by PAP staining of a single cervical smear, the overall rate of abnormalities being 2.8%. Furthermore, the age-adjusted prevalence of HIV antibodies was found to be considerably lower in 270 cervical-carcinoma patients (3% HIV-positive) in comparison with non-cancer patients. Thus there was no association observable between the prevalence of HIV infections and the frequency of cervical cytological abnormalities or cervical cancer in the setting of this cross-sectional study.

No abstract

Separation of metal ions by functionalized soluble polymers using membrane filtration has been investigated. Actinide elements and members from the transition groups and rare earth elements have been bound to polymeric chelatogenes as a function of pH. Sixteen different polymers and derivatives based on poly(ethylenimine), poly(vinylalcohol), poly(urethane), and poly(acrylic acid) have been studied in terms of their capacity and selectivity. Binding studies and cleavage experiments have been carried out by application of membrane filtration for several metals and polychetatogenes. Finally, the stability of polymers and membranes has been studied and found to be sufficient for selective separation of actinide ions.

Makromolekulare Chelatogene wurden zur Komplexierung mit verschiedenen Metallen in homogener Phase unter Anwendung der Membranfiltration synthetisiert und untersucht. Eine Anzahl von wasserlöslichen Basispolymeren, wie z. B. Poly(vinylamin), Poly(acrylsäure), Poly(ethylenimin), ihre Copolymere und Derivate wurden im Hinblick auf ihre Anwendung zur Komplexbildung von Übergangsmetallen dargestellt und untersucht. Die Molmassen der Polymere lagen zwischen 20000 und 200000 Daltons. Die Anwendung der Membranfiltration ermöglicht die Abtrennung von überschüssigen Metallionen vom Polymerkomplex in einem kontinuierlichen oder diskontinuierlichen Verfahren. Studien über die Metallbindungskapazitäten der Polymerliganden zeigten, daß es möglich ist, makromolekulare Chelatogene darzustellen, die für verschiedene Metalle selektiv sind. Danach verbesserte die Einführung von chelatogenen Gruppen, wie Iminodiessigsäure, Thioharnstoff, Pyridin‐2‐aldimin und andere, signifikant die Selektivität für die Metalle Kupfer, Nickel, Palladium, Quecksilber, Eisen, Gold und Platin. Zur Regenerierung der Polymerliganden kann die Elektrolyse oder Protolyse verwendet werden. Die makromolekularen Komplexe blieben unabhängig vom komplexierten Metall und des polymeren Chelatogens wasserlöslich. Nach diesen Studien können bestimmte Metalle selektiv aus Abwasser oder anderen verdünnten Lösungen durch die Anwendung von polymeren Chelatogenen in homogener Phase entfernt werden.