The seasonal effects on the encrustation of charophytes in two hard-water lakes.

Encrustation and element content of six charophyte species from two hard-water lakes were investigated monthly for a period of 1 year. Seasonal patterns were analyzed for the interaction of water chemistry. Encrustation followed a seasonal pattern for Chara contraria, Chara subspinosa, and Nitellopsis obtusa in Lake Krüselin and for Chara globularis and Chara tomentosa in Lake Lützlow. However, no seasonality in the precipitated CaCO3 was observed for C. subspinosa in Lake Lützlow and for C. tomentosa in Lake Krüselin, indicating a lake-specific dependency. Species-specific encrustation was found. Chara contraria and N. obtusa encrusted the most in June and August, whereas C. subspinosa and Nitella flexilis/opaca exhibited lowest encrustation in March and April. The precipitated CaCO3 of charophytes correlated negatively to the concentration of total inorganic carbon in both lakes. Element content of plant dry weight was species-specific for Ca and K, and lake-specific for Mg. No specific pattern was found for the TP and Fe contents. The results showed seasonal, species, and lake-specific influences on the encrustation of charophytes.

Bioremediation approach using charophytes-preliminary laboratory and field studies of mine drainage water from the Mansfeld Region, Germany.

Mine drainage water from the Schlenze stream, Mansfeld Region, Central Germany, which have shown an increase in heavy metal concentrations of Cd2+, Cu2+, Pb2+, and Zn2+, was used to investigate the bioremediation potential of charophytes. The removal of heavy metals by Chara subspinosa from the water was tested in single- and multi-metal additions. The uptake capacity of C. subspinosa decreased during the course of the experiment and was higher in single-metal addition than in multi-metal addition of Pb2+, Zn2+, and Cd2+. Accumulation of heavy metals in the carbonate encrustation of charophytes was far lower than those to which they were exposed. Cu, Cd, Pb, and Zn co-precipitated more in the encrustation of C. subspinosa exposed to single-metal approach than to multi-metal approach. The carbonate composition of charophytes was influenced by the water chemistry. Content of Na in the carbonate encrustation correlated with the Na+ concentration of the respective water. The toxic effect of heavy metals on photosynthesis was species-specific. Electron transport rates (ETRmax) were higher in Chara tomentosa than in C. subspinosa. Charophytes withstand the heavy metal concentrations when diluted with river water from the Altarm cut-off lake and can therefore be used for the bioremediation of diluted mine drainage waters by co-precipitating Cd, Cu, and Zn.

Age and site-specific pattern on encrustation of charophytes.

Encrustation and element content (Ca, Fe, K, Mg and P) of charophytes was studied along plant thalli to investigate the dependency of thallus age and site-specificity. Charophytes were collected from five sampling sites (Angersdorfer Teiche, Asche, Bruchwiesen, Krüselinsee and Lützlower See) which were distinct with respect to water chemistry. Furthermore, photosynthesis was measured to identify the physiological state of plants in habitat waters and with the addition of different ion concentrations (Ca2+, K+, Mg2+ and Na+). Age pattern on encrustation of charophytes was site-specific: carbonate content increased from the youngest to the oldest part (Angersdorfer Teiche), younger parts were less encrusted than older parts in Asche, Bruchwiesen and Krüselinsee, whereas encrustation in Lützlower See was the same along plants thallus. Charophytes showed species-specific encrustation in investigated sites. Encrustation of C. hispida in Angersdorfer Teiche was also as high as of individuals from hard-water lakes irrespective of 10.15 mS cm-1 (salinity of 6.3). For species growing in Angersdorfer Teiche, K/Na content and photosynthesis was lowest when compared to other sites. Photosynthesis of charophytes was enhanced after the addition of KCl and adversely affected by CaCl2, MgCl2 and NaCl. In summary, it was shown that encrustation of charophytes in water sites with strong ion anomalies could be as high as in hard-water lakes. It is assumed that ion composition, rather than ion concentration of Na+, Mg2+ and SO42-, impact on the encrustation of charophytes. The age pattern on encrustation in this study showed a strong site-specificity, whereas encrustation of charophytes was species-specific. Ion concentrations, either of habitats or actively added in laboratory measurements, impact on encrustation, element content and photosynthesis of charophytes.

Report of the clinical protocol committee: development of randomized trials for malignant bowel obstruction.

Malignant bowel obstruction (MBO) is a commonly encountered palliative care problem. There have been very few comparative trials in this area, and consequently there is very little clinical evidence upon which therapy can be rationally based. The purpose of this paper is to highlight the discussion and decision-making process that was undertaken by the Clinical Protocol Subcommittee during the development of a proposed clinical trial of best medical care versus surgical or endoscopic treatment for MBO. The development of the proposed clinical trials followed an orderly process. The first step taken was a discussion of a specific definition for MBO. Once agreed upon, this definition helped identify inclusion and exclusion criteria for the proposed trial. This was followed by an extensive literature review, which helped define both surgical and endoscopic approaches to MBO as well as what constituted best medical care. An extensive discussion was then undertaken concerning the best outcome measure of success for medical, surgical, and endoscopic interventions. All of the above steps culminated in two proposed protocols, one for MBO of the small intestine distal to the ligament of Treitz and a second for colonic obstructions. The small intestinal trial is designed to compare surgical intervention versus best medical care, whereas the colonic trial seeks to compare surgery with endoscopically-placed intraluminal stents coupled with best medical care.

In Vivo Testing of Extracorporeal Membrane Ventilators: iLA-Activve Versus Prototype I-Lung.

A side-by-side comparison of the decarboxylation efficacy of two pump-driven venovenous extracorporeal lung assist devices, i.e., a first prototype of the new miniaturized ambulatory extracorporeal membrane ventilator, I-lung versus the commercial system iLA-activve for more than a period of 72 hours in a large animal model. Fifteen German Landrace pigs were anesthetized and underwent mechanical hypoventilation to induce severe hypercapnia. Decarboxylation was accomplished by either the I-lung or the iLA-activve via a double lumen catheter in the jugular vein. Sham-operated pigs were not connected to extracorporeal devices. Cardiovascular, respiratory, and metabolic parameters were continuously monitored, combined with periodic arterial blood sampling for subsequent clinical blood diagnostics, such as gas exchange, hemolysis, coagulation parameters, and cytokine profiles. At the termination of the studies, lung tissue was harvested and examined histologically for pulmonary morphology and leukocyte tissue infiltration. Both extracorporeal devices showed high and comparable efficacy with respect to carbon dioxide elimination for more than 72 hours and were not associated with either bleeding events or clotting disorders. Pigs of both groups showed cardiovascular and hemodynamic stability without marked differences to sham-operated animals. Groups also did not differ in terms of inflammatory and metabolic parameters. We established a preclinical in vivo porcine model for comparative long-term testing of I-lung and iLA-activve. The I-lung prototype proved to be safe and feasible, providing adequate decarboxylation without any adverse events. Once translated into the clinical treatment, the new miniaturized and transportable I-lung device might represent a promising tool for treating awake and mobilized patients with decompensated pulmonary disorders.

The peroneal reaction time (PRT)--reference data in a healthy sample population.

BACKGROUND: Acute ankle sprains can result in severe residual symptoms, such as chronic ankle instability from weakness of the ligamentous complex or neuromuscular deficits. Measuring peroneal reaction time (PRT) has become a commonly accepted procedure for evaluating proprioceptive deficits. METHODS: The present experimental study was conducted to determine the effects of anthropometric factors on PRT in 120 healthy volunteers. The patients were asked to stand on a platform with a tilting mechanism. Surface electrodes were used to record peroneal muscle activity in response to sudden inversion stress. The reaction of the peroneal muscles was analyzed using electromyography. RESULTS: The statistical analysis showed similar intra-individual and inter-individual values for PRT. The results for the muscle groups measurements, however, varied considerably. PRT seems to increase significantly with age (long peroneal muscle: p < 0.0001, short peroneal muscle: p = 0.004). CONCLUSIONS: PRT was found to be an objective parameter that is unaffected by extrinsic and intrinsic factors. The present study, however, also showed that PRT significantly increases with age. As for studies on PRT, as well as for clinical routine, it is important to consider the patients' ages.

Cardiac Wegener's granulomatosis masquerading as left atrial myxoma.

A 56-year-old woman was referred with mitral regurgitation, left ventricular dysfunction, and a sessile mass on the anterior leaflet of her mitral valve. The initial impression from echocardiography was that she had a left atrial myxoma. At operation, we found an intense inflammatory process diagnosed as Wegener's granulomatosis. It also involved the aortic valve and contiguous myocardium.

Imaging studies in the diagnosis of urogenital trauma.

UNLABELLED: Polytraumatized patients often present with urological injuries. After hemodynamic stability is maintained urologists are consulted to evaluate diagnostic and therapeutic interventions. The following article describes how to handle the work-up of patients with injuries to specific urogenital organs: the importance of clinical examination, ultrasonography, computed tomography (CT), magnetic resonance imaging (MRI), angiography as well as organ-specific radiologic studies such as intravenous pyelography or cystography are discussed. CONCLUSION: Even though injuries to the urogenital tract are rarely initially life--threatening, a fast, reliable and adequate diagnostic algorithm has to be established to avoid any delay of specific treatment. Urologists should be familiar with the indications, range and accuracy of these procedures in the diagnosis of urogenital trauma.