Comet-FISH using peptide nucleic acid probes detects telomeric repeats in DNA damaged by bleomycin and mitomycin C proportional to general DNA damage

For the optimal use of anticancer drugs a knowledge of the whole spectrum of side-effects is required. A potential hazard, so far only scarcely investigated, is uncontrolled effects of drugs such as bleomycin (BLM) and mitomycin C (MMC) on telomere shortening in non-cancerous tissues of the treated person. For the first time, directly labelled telomere-specific peptide nucleic acid (PNA) hybridization probes were applied in comet-FISH to detect DNA fragmentation on an intermediate scale. The effects of BLM and MMC were measured in peripheral blood cells of three human volunteers, following ex vivo incubation. Fragmentation of telomeres and subtelomeric regions was highly specifically detected by the comet-FISH assay, a combination of the comet assay and fluorescence in situ hybridization. As a technical detail, the effects of the hybridization procedure have been studied on the level of single comets. Image analysis before and after the hybridization process reveals a small decrease in the detected fragmented DNA, probably due to diffusion of small fragments. It could not only be shown that both drugs actually induce breaks in telomere-associated DNA, but also that the comet-FISH technique, as a quantitative approach, is a useful tool for the detection and evaluation of the role of sequence-specific DNA damage after mutagenic action. The breakage frequency for DNA of or adjacent to telomeric repeats was found to be proportional to that of the total DNA, which hints at random induction of DNA breaks by BLM and MMC. In terms of therapy, the results indicate that no over- or under-proportional effects on telomeres of BLM or MMC need be expected.     

An IFN-beta-albumin fusion protein that displays improved pharmacokinetic and pharmacodynamic properties in nonhuman primates.

The long half-life and stability of human serum albumin (HSA) make it an attractive candidate for fusion to short-lived therapeutic proteins. Albuferon (Human Genome Sciences [HGS], Inc., Rockville, MD) beta is a novel recombinant protein derived from a gene fusion of interferon-beta (IFN-beta ) and HSA. In vitro, Albuferon beta displays antiviral and antiproliferative activities and triggers the IFN-stimulated response element (ISRE) signal transduction pathway. Array analysis of 5694 independent genes in Daudi-treated cells revealed that Albuferon beta and IFN-beta induce the expression of an identical set of 30 genes, including 9 previously not identified. In rhesus monkeys administered a dose of 50 microg/kg intravenously (i.v.) or subcutaneously (s.c.) or 300 microg/kg s.c., Albuferon beta demonstrated favorable pharmacokinetic properties. Subcutaneous bioavailability was 87%, plasma clearance at 4.7-5.7 ml/h/kg was approximately 140-fold lower than that of IFN-beta, and the terminal half-life was 36-40 h compared with 8 h for IFN-beta. Importantly, Albuferon beta induced sustained increases in serum neopterin levels and 2',5' mRNA expression. At a molar dose equivalent to one-half the dose of IFN-beta, Albuferon beta elicited comparable neopterin responses and significantly higher 2',5'-OAS mRNA levels in rhesus monkeys. The enhanced in vivo pharmacologic properties of IFN-beta when fused to serum albumin suggest a clinical opportunity for improved IFN-beta therapy.     

Die Gattung Knemidocoptes (Acari,Sarcoptoidea)

Zusammenfassung Es wird vorgeschlagen, die Gattung Knemidocoptes Fürstenberg, 1870, auf Grund zahlreicher charakteristischer Merkmale als eigene Familie in der Überfamilie Sarcoptoidea Dubinin, 1951, zu führen. Die Familie Knemidocoptidae besitzt nur eine Gattung mit 9 verschiedenen Arten: K. glaberrimus, K. philomelae, K. fossor, K. mutans, K. jamaicensis, K. pilae, K. laevis, K. gallinae, K. prolificus. Von jeder Species wird eine ausführliche Darstellung gegeben und soweit bekannt ihre Biologie und Pathogenität besprochen. Das bisher noch nicht beobachtete Männchen von K. jamaicensis wird beschrieben. Ein Bestimmungsschlüssel der Gattung Knemidocoptes wird angeführt.Mit 20 Textabbildungen     

Triazin-polymere. II. Polyphenylentriazine

Condensation of benzamidine hydrochloride with acetanhydride gives 2-methyl-4.6-diphenyl-s-triazine with yields of more than 90%. The corresponding reaction of terephthaldiamidine dihydrochloride leads to poly[(6-methyl-2.4-s-triazinediyl)-1.4-phenylene] of low degree of polymerization, soluble in conc. sulfuric acid. Benzamidine-N-carboxylic acid ethylester is converted to 2-hydroxy-4.6-diphenyl-s-triazine in a yield of 99% by heating. Terephthaldiamidine-di-N-carboxylic acid ethylester decomposes by heat treatment under loss of ethyl carbamate to the insoluble white poly[(6-hydroxy-2.4-s-triazinediyl)-1.4-phenylene].     

Drug-induced intrahepatic cholestasis: characterization of different pathomechanisms

The pathogenesis of intrahepatic cholestasis in rats was studied using isolated perfused livers as an experimental model. Three basic mechanisms were differentiated: 1. Permeabilization of the bilio-sinusoidal barrier associated with electron microscopic alterations of the tight junctional complexes was found in livers of rats treated with -naphthylisothiocyanate (ANIT, 250 mg/kg body weight). Consequences of these alterations were: reflux of bile constituents such as taurocholate and sulfobromophthalein and increased access to the biliary space of paracellular markers such as inulin and sucrose. The clear-cut mechanism of ANIT cholestasis was used to distinguish other mechanisms of intrahepatic cholestasis. 2. Inhibition of the basic process of fluid secretion was found to be the primary event in the development of cholestasis induced by estrogens. After 5 days of treating rats with ethinyl estradiol (5 mg/kg/day), bile flow was diminished in isolated livers while the permeability of the biliary tract to sucrose and inulin was not affected. Accordingly, the maximal concentration of taurocholate in bile was increased, indicating that its secretion was sustained. The same effect was observed after 1 week of treatment with the depot estrogen estradiol valerate (1 mg/kg/week). After 3 weeks of treatment, however, the taurocholate concentration in bile was lowered and the clearance of sucrose was increased. Bile flow remained at the same cholestatic level for 20 weeks. These results suggest that estrogens have the potency to increase tight junctional permeability only in a second step in the development of cholestasis, following the inhibition of bile flow. 3. An additional mode of secretory inhibition was induced by lowering the concentration of Ca²⁺ in the perfusate of isolated liver. Using ANIT-pretreated livers, i. e., livers with very low capacity to secrete foreign dyes, a high rate of efflux of sulfobromophthalein into the perfusate of preloaded livers suggests stimulation of the efflux of cholephilic solutes across the sinusoidal membrane of liver cells.The results demonstrate that the term intrahepatic cholestasis comprises a number of different sites of interference with the complex process of bile secretion.Dedicated to Professor Dr. med. Herbert Remmer on the occasion of his 65th birthday     

Distal rectus femoris surgery in children with cerebral palsy: results of a Delphi consensus project

PurposeThe purpose of this study was for an international panel of experts to establish consensus indications for distal rectus femoris surgery in children with cerebral palsy (CP) using a modified Delphi method.MethodsThe panel used a five-level Likert scale to record agreement or disagreement with 33 statements regarding distal rectus femoris surgery. The panel responded to statements regarding general characteristics, clinical indications, computerized gait data, intraoperative techniques and outcome measures. Consensus was defined as at least 80% of responses being in the highest or lowest two of the five Likert ratings, and general agreement as 60% to 79% falling into the highest or lowest two ratings. There was no agreement if neither threshold was reached.ResultsConsensus or general agreement was reached for 17 of 33 statements (52%). There was general consensus that distal rectus femoris surgery is better for stiff knee gait than is proximal rectus femoris release. There was no consensus about whether the results of distal rectus femoris release were comparable to those following distal rectus femoris transfer. Gross Motor Function Classification System (GMFCS) level was an important factor for the panel, with the best outcomes expected in children functioning at GMFCS levels I and II. The panel also reached consensus that they do distal rectus femoris surgery less frequently than earlier in their careers, in large part reflecting the narrowing of indications for this surgery over the last decade.ConclusionThis study can help paediatric orthopaedic surgeons optimize decision-making for, and outcomes of, distal rectus femoris surgery in children with CP.Level of evidenceV     

Of markets,technology, patients and profits

In this paper I: (1) Describe something of the present situation in the United States and briefly contrast this with the state of affairs in other nations of the industrialised world. I emphasise health care but also allude to other social conditions: health care is merely one institution of a society and, just as do its other institutions, the system of health care reflects the basic world-view of that society. (2) Sketch the world-view and the philosophy which underwrites the use of a market system in distributing what are acknowledged to be critically important social goods like health care and higher education. I show that a well-functioning market can indeed be useful when it comes to distributing some, but not when distributing other goods. (3) Suggest that when competition and the market are used to regulate health care, technology—instead of being used to benefit patients—is apt to be used primarily to maximise individual profit: it becomes a weapon between what is often painted as warfare among health care providers and institutions. I argue that this state of affairs is based on an undue emphasis upon the demands of individual freedom to the detriment of the community. Finally (4) I suggest an alternative approach to balancing individual with communal interests, an approach which is neither based on a predominance of one with neglect of the other, nor on a dialectic balance between them, but rather upon an approach which sees both individual and communal interests as modifying forces in a complex homeostatic balance. Individual success, in any civilised sense of the term, is possible only in a viable and well-functioning community, and a well-functioning community is not possible without individual success: the two are inevitably interdependent and linked.     

Electrophysiological indices of acute effects of ethanol on involuntary attention shifting

Dose-related effects of ethanol (placebo, 0.30, and 0.60 g/kg) on behavioral and event-related brain potential (ERP) indices of involuntary attention shifting of audition were investigated. ERPs were recorded from 11 healthy social drinkers during a forced-choice reaction-time (RT) task. Subjects were presented with 100 and 200 ms tones (P = 0.50 for each) with a constant inter-stimulus interval (ISI) of 1 s. The task was to press either of two buttons, depending on the tone duration. The majority of the tones (“standards”) were of 700 Hz (P = 0.82). Occasionally, however, the frequency of the tones changed, deviating either slightly (750 Hz), moderately (900 Hz), or widely (1200 Hz; P = 0.06 for each) from the standard frequency. In accordance with previous findings, the task-irrelevant frequency deviations prolonged the RT. This RT prolongation was attenuated by alcohol with the 0.3 g/kg dose, thus suggesting less distraction by irrelevant stimulus deviations under the influence of ethanol. Furthermore, the P3a, reflecting involuntary attention shifting, was suppressed by alcohol even with the 0.3 g/kg dose. These findings demonstrate a detrimental effect of alcohol on involuntary attention shifting, evident with doses considerably smaller than previously described, and still juridically acceptable in road traffic in most countries. Received: 19 December 1997/Final version: 26 May 1998     

Analysis of seasonal training volume and working capacity in elite female rowers.

Preceding the 1988 Olympic Games 6 elite female rowers were regularly subjected to an exercise test on a rowing ergometer (REM-test) with a time interval of about 5 weeks. Daily training volume was analysed in terms of rowed kilometres (RKM) and training time (TOTMIN, rowing and land training). The purpose of this study was to investigate the training volume during a season and to study possible changes in the working capacity of elite female rowers. The REM-test consisted of 3 consecutive blocks: 3 min warming up, 5 min standard load at anaerobic threshold and 2 min "all-out". Blood lactic acid concentration (LA) was determined for the construction of a LA-power curve. The power at 4.0 mmol/l (P4) was estimated as a measure of the aerobic capacity. The "all-out" score was used for calculating the maximal power (PM). Results show that both RKM and TOTMIN increase (range resp. 40-400% and 20-25%) when compared with the initial value. P4 also increases, in parallel with changes in both RKM and TOTMIN, with 8-10% of the initial value. PM increases continuously during the season up to 10% of its initial value. However, based on maximal heart rate and lactate values, it is concluded that PM was maximal in only 15% of the tests. Our data suggests that evaluation of training volume in elite female rowers is better done with P4 than with PM. The behaviour of P4 shows a parallel with the seasonal changes in the training load.(ABSTRACT TRUNCATED AT 250 WORDS)