Wetting in a phase separating polymer blend film: quench depth dependence

We have used 3He nuclear reaction analysis to measure the growth of the wetting layer as a function of immiscibility (quench depth) in blends of deuterated polystyrene and poly(alpha-methylstyrene) undergoing surface-directed spinodal decomposition. We are able to identify three different laws for the surface layer growth with time t. For the deepest quenches, the forces driving phase separation dominate (high thermal noise) and the surface layer grows with a t(1/3) coarsening behavior. For shallower quenches, a logarithmic behavior is observed, indicative of a low noise system. The crossover from logarithmic growth to t(1/3) behavior is close to where a wetting transition should occur. We also discuss the possibility of a "plating transition" extending complete wetting to deeper quenches by comparing the surface field with thermal noise. For the shallowest quench, a critical blend exhibits a t(1/2) behavior. We believe this surface layer growth is driven by the curvature of domains at the surface and shows how the wetting layer forms in the absence of thermal noise. This suggestion is reinforced by a slower growth at later times, indicating that the surface domains have coalesced. Atomic force microscopy measurements in each of the different regimes further support the above. The surface in the region of t(1/3) growth is initially somewhat rougher than that in the regime of logarithmic growth, indicating the existence of droplets at the surface.

[Comprehension and evaluation of drug risks through spontaneous notification]. / Erfassung und Bewertung von Arzneimittelrisiken durch Spontanmeldungen.

Risk/benefit analysis of drugs requires not only the reporting and documentation of adverse drug reactions in clinical trials but also a spontaneous reporting system for the detection of rare adverse reactions to drugs. A central aspect of any spontaneous reporting system is assessment of causality on the basis of detailed case histories. However, besides the qualitative description of adverse drug reactions, information about the incidence of such reactions has to be obtained as well so that their frequency, and thus the risk involved, can be established.

Overview of postmarketing experience with ofloxacin in Germany.

Clinical trials with ofloxacin have shown that adverse drug events (ADEs) occurred in between 2.4% (Phase II) and 3.1-7.3% (Phase IV) of patients treated and were mostly mild. As with any other drug the true spectrum of rare events can only be fully appreciated after marketing. Since the launch of ofloxacin in June 1985 about 3.5 million patients have been treated in Germany, calculated on the basis of a mean daily dose of 400 mg ofloxacin and a mean duration of treatment of seven days. During these 2.5 years 985 spontaneous national reports of ADEs have been obtained and include rare adverse events (e.g. hallucination, psychotic reaction and shock), not seen in clinical trials. The present status of results from postmarketing surveillance is shown and discussed. The favourable overall risk:benefit ratio of ofloxacin appears unchanged.

Side effects of ofloxacin in clinical trials and in postmarketing surveillance.

Data derived from clinical trials of ofloxacin in 15,962 patients show that the incidence rate of adverse drug events was 4.27 per 100 patients. Symptoms were generally mild and related to the gastrointestinal tract, nervous system or hypersensitivity reactions in rank order. On the other hand, spontaneous reports obtained during postmarketing surveillance involving 1.5 million patients showed that the most frequent adverse drug events were related to the nervous system; next in order of frequency were hypersensitivity reactions and gastrointestinal symptoms. A comparison of the data obtained from clinical trials and postmarketing surveillance revealed no change in the favourable overall benefit:risk ratio of ofloxacin. Possible reasons for the different patterns of adverse drug events are discussed.

[Combined chemotherapy-radiotherapy study of small cell bronchial carcinoma: chemo-/radiotherapy vs radio-/chemotherapy]. / Kombinierte Chemotherapie-Radiotherapie-Studie des kleinzelligen Bronchuskarzinoms (CCR-Studie): Chemo-/Radiotherapie gegen Radio-/Chemotherapie.

The authors studied the effect of a chemo-/radiotherapy or radio-/chemotherapy on 52 cases of microcellular bronchial carcinoma, classification "limited disease". The survival curves were slightly better for the patients submitted to primary chemotherapy, but the difference was not statistically significant, and the curves coincided again after 18 months. 60 to 80% of the patients had no complaints or only unimportant complaints during more than half of their survival time. In 23 patients with "extensive disease" who received only a symptomatic therapy or a combined palliative chemotherapy, chemotherapy had a slightly better effect, but this was not statistically significant.

[Chemotherapy of inoperable endothoracic tumours (results of the Karrer and aco polycytostatic therapy) (author's transl)]. / Problematik der Chemotherapie inoperabler endothorakaler Tumoren--Erfahrungen und Ergebnisse mit zwei verschiedenen polyzytostatischen Schemata (Karrer und ACO) aus den Jahren 1971--1977 am Krankenhaus Grosshansdorf.

The success of chemotherapy of inoperable endothoracic cancer largely depends on interdisciplinary cooperation. 30 years of research have succeeded in developing some promising combinations of cytostatic agents. Administered sequentially they are better tolerated and this has made outpatient treatment possible. 87 persons had polycytostatic therapy according to the Karrer/Sighart formula. It was followed by a difinite improvement in the general condition of the patients, but without any substantial lengthening of the average survival time. The ACO scheme (Seeber/Schmidt) has been used since April 1977 in 42 persons. Preliminary results indicate a definite prologation of survival time, especially in cases of small-cell bronchogenic carcinoma.