A mechanistic model to study the thermal ecology of a southeastern pacific dominant intertidal mussel and implications for climate change.

Developing mechanistic models to predict an organism's body temperature facilitates the study of physiological stresses caused by extreme climatic conditions the species might have faced in the past or making predictions about changes to come in the near future. Because the models combine empirical observation of different climatic variables with essential morphological attributes of the species, it is possible to examine specific aspects of predicted climatic changes. Here, we develop a model for the competitively dominant intertidal mussel Perumytilus purpuratus that estimates body temperature on the basis of meteorological and tidal data with an average difference (+/-SE) of 0.410 degrees +/- 0.0315 degrees C in comparison with a field-deployed temperature logger. Modeled body temperatures of P. purpuratus in central Chile regularly exceeded 30 degrees C in summer months, and values as high as 38 degrees C were found. These results suggest that the temperatures reached by mussels in the intertidal zone in central Chile are not sufficiently high to induce significant mortality on adults of this species; however, because body temperatures >40 degrees C can be lethal for this species, sublethal effects on physiological performance warrant further investigation. Body temperatures of mussels increased sigmoidally with increasing tidal height. Body temperatures of individuals from approximately 70% of the tidal range leveled off and did not increase any further with increasing tidal height. Finally, body size played an important role in determining body temperature. A hypothetical 5-cm-long mussel (only 1 cm longer than mussels found in nature) did reach potentially lethal body temperatures, suggesting that the biophysical environment may play a role in limiting the size of this small species.

The Faces Symbol Test, a newly developed screening instrument to assess cognitive decline related to multiple sclerosis: first results of the Berlin Multi-Centre FST Validation Study.

Reliable, language-independent, short screening instruments to test for cognitive function in patients with multiple sclerosis (MS) remain rare, despite the high number of patients affected by cognitive decline. We developed a new, short screening instrument, the Faces Symbol Test (FST), and compared its diagnostic test characteristics with a composite of the Digit Symbol Substitution Test (DSST) and the Paced Auditory Serial Addition Test (PASAT), in 108 MS patients and 33 healthy controls. An Informant-Report Questionnaire, a Self-Report Questionnaire, and a neurologist's estimation of the Every Day Life Cognitive Status were also applied to the MS patients. The statistical analyses comprised of a receiver operating characteristic analysis for test accuracy and for confounding variables. The PASAT and DSST composite score estimated that 36.5% of the MS patients had cognitive impairment. The FST estimated that 40.7% of the MS patients were cognitively impaired (sensitivity 84%; specificity 85%). The FST, DSST and PASAT results were significantly correlated with the patients' physical impairment, as measured by the Expanded Disability Status Scale (EDSS). The results suggest that the FST might be a culture-free, sensitive, and practical short screening instrument for the detection of cognitive decline in patients with MS, including those in the early stages.

Thermoregulatory behavior, heat gain and thermal tolerance in the periwinkle Echinolittorina peruviana in central Chile.

The amount of solar radiation absorbed by an organism is a function of the intensity of the radiation and the area of the organism exposed to the source of the radiation. Since the prosobranch gastropod Echinolittorina peruviana is longer than it is wide, its areas of the lateral sides are approximately twice as large as the areas of the frontal and dorsal faces. We quantified the orientation of the intertidal prosobranch E. peruviana with respect to the position of the sun and solar heat gain in the different orientations. In the field, 80.9% of the E. peruviana monitored on sunny summer days tended to face the sun frontally or dorsally while only 19.1% faced the sun with the larger lateral sides. On overcast summer or on winter days, this trend was not observed. We then show that the body temperature of individuals increases more rapidly and reaches higher equilibriums when the lateral sides are facing the sun than when they face the sun with either of the smaller frontal or dorsal sides. These results therefore show that the orientation behavior of E. peruviana is thermoregulatory and that it permits the organisms to maintain lower temperatures on hot summer days.

[Urinary enzyme excretion in cephalothin therapy in adults and children]. / Harnenzymausscheidung während einer Therapie mit Cephalothin bei Erwachsenen und Kindern.

A damage of the kidney, particularly of proximal tubular cells, can be indicated by an increased concentration of definite enzymes in urine. After gynecological operation the repeated application of 8 g cephalothin daily provokes an higher increase of enzyme concentrations in urine than the application of ampicillin under the same conditions. These results show that cephalothin produces a slight alteration of tubular cells, probably without practical importance. In contrast to this, in children a total dose of 1.5 up to 6 g cephalothin, administered after an operative correction of vesikoureterale reflux, provokes no marked changes in urinary enzyme excretion. Probably, in these children the determination of urinary enzyme excretion is not a suitable parameter to demonstrate a slight tubulotoxic damage.

[Results of follow-up studies in children with megaureters]. / Nachuntersuchungsergebnisse bei Kindern mit Megaureteren.

It is reported on the results of after-examinations in children with megaureters. The average interval between first operation and last after-examination is 8.1 years (1 to 14 years). Of altogether 63 children ten died, eight of their disease, including the postoperative complications. Eleven children were nephroureterectomized. In spite of the time of satisfying results concerning the renal function the prognosis is uncertain, particularly of the children with bilateral malformation. The number of the infections of the urinary tract is large and the deterioration of the function due to pyelonephritis is not to be foreseen. Changes or modifications of the operation technique and a strict dispensary care of the children let us hope for an improvement of the results during the next years.