Therapeutic failures after gastric bypass operations for morbid obesity

BACKGROUND: Although gastric bypass is an effective treatment for morbid obesity, the postoperative results are unsatisfactory in 10% of all patients. Therapeutic failures after an operation performed with the sole purpose of reducing the risk of obesity-associated diseases have to be taken seriously. The goal of this study was to investigate the causes of these failures. METHOD: From 1979 to 1993, 165 gastric bypass operations (technique: Mason-Griffen) were performed. Long-term results were obtained in 60 patients after an average of 6.6 years (range 3-13). On follow-up all patients were examined and asked about their level of satisfaction with the weight loss achieved and changes in eating habits. RESULTS: In 6 patients the weight reduction was regarded as insufficient (BMI > 35 and reduction of BMI < 10). The causes of these failures were technical in 3 cases (gastric pouch to 0 large in 1, dilatation of gastrojejunostomy in 2). Three patients had a high calorie intake through an intact gastric bypass by snacking. Three patients regarded the operation as a failure although they had achieved significant weight loss, because they could no longer eat the usual amounts of food. CONCLUSION: Correct surgical technique and preoperative information on the changes in eating habits after a gastric bypass operation are the most important steps in preventing therapeutic failures.     

DIC image reconstruction on large cell scans

The width of the emission spectrum of a common fluorophore allows only for a limited number of spectral distinct fluorescent markers in the visible spectrum, which is also the regime where CCD-cameras are used in microscopy. For imaging of cells or tissues, it is required to obtain an image from which the morphology of the whole cell can be extracted. This is usually achieved by differential interference contrast (DIC) microscopy. These images have a pseudo-3D appearance, easily interpreted by the human brain. In the age of high throughput and high content screening, manual image processing is not an option. Conventional algorithms for image processing often use threshold-based criteria to identify objects of interest. These algorithms fail for DIC images as they have a range from dim to bright with an intermediate intensity equal to the background, so as to produce no clear object boundary. In this article we compare different reconstruction methods for up to 100 MB-large DIC images and implement a new iterative reconstruction method based on the Hilbert Transform that enables identification of cell boundaries with standard threshold algorithms.     

Influence of total surface area of core material on yield of deposited coacervate

The neuronal cytoskeleton is one of the most profoundly altered organelles in late life neuro-degenerative disorders that are characterized by progressive impairments in cognitive abilities. The elucidation of the protein building blocks of these organelles as well as advances in understanding how these proteins become altered in Alzheimer's disease (AD) and other less common dementing illnesses, i.e., diffuse Lewy body disease (DLBD) or the Lewy body variant of AD (LBVAD), will provide insights into the molecular basis of these disorders. Within, we review evidence that normal adult human tau is abnormally phosphorylated and converted into the subunits of AD paired helical filaments (PHFs), and that Lewy bodies (LBs) represent accumulation of altered neurofilament (NF) triplet subunits. Although the precise biological consequences of PHF and LB formation in neurons is unknown, growing evidence suggests that the formation of PHFs and LBs from normal neuronal cytoskeletal proteins could have deleterious effects on neuronal function and survival. Finally, insights into the composition of PHFs and LBs could lead to the development of novel strategies for the timely and accurate diagnosis of AD, DLBD and the LBVAD.     

Nanosized titania derived from a novel sol-gel process for ammonia gas sensor applications

Highly redispersible anatase nanoparticles were prepared by a novel sol-gel based hydrothermal process for gas sensing applications. Thin titania films composed of nanoparticles were deposited on Au interdigital electrodes by dip-coating, annealed and tested in a gas test bench at 350 °C. The anatase films showed a very high sensitivity towards ammonia and no cross interference by CO₂, O₂ and C₃H₈. To classify the sensor as an ammonia gas sensor, a comparison with other sensor designs from literature has been performed.     

Daten amtlicher Lebensmittelkontrolle in Deutschland – Analyse und Erfassung der Unterschiede

Whether or not food control data reported according to former directive 89/397 EEC in Germany are comparable and whether or not recording or aggregation differences appear between the Länder should be proved within a project conducted by the BVL. The result of a data analysis of official control data was, that indicators like “the percentage of establishments with non-conformity reports” were not comparable between the Länder. It should be analysed, whether or not this is based on structural differences in the Länder and/or based on a matter of recording or aggregation differences. An analysis of these differences was conducted with the help of the Länder in several local authorities and upper authorities. The towns and authorities were chosen at random. Structured interviews were conducted with food control experts. It could be recognized that recording differences appeared for inspection data. These refer mainly to the deepness of data recording, the total number of recorded establishments, associated controls, and additional establishment information. Aggregation differences were mainly found for the sample data. Here, two main points are important: (1) which samples were actually aggregated; this is which sampling reasons were taken into account (population)? and (2) which samples were summarised in which product group. Less concise are differences in sample planning, the analysis spectrum for one sample, the assessment of analysis results and the consequence of the sample analysis outcome (advice, sanction). Since a statistical analysis of these food control data is difficult because of the mentioned differences in data recording and data aggregation, a harmonized usage of definitions for and recording as well as aggregation of these data is worthwhile. Not till then data could be the basis for a meaningful statistic and picture the success or failure of control activities.     

Investigation of the photovoltage in por-Si/p-Si structures by the pulsed-photovoltage method

Photovoltaic phenomena in the structures por-Si/p-Si were investigated by the pulsed photovoltage method in the time interval 100 ns-10 ms using irradiation with nanosecond laser pulses with photon energies 1.4, 2.0, 2.8, and 3.7 eV. The data obtained show that besides the barrier photovoltage, due to the separation of nonequilibrium charge carriers in the space-charge region of p-Si at the por-Si/p-Si interface, there also exists an efficient mechanism of photovoltage formation due to charging of the surface of the por-Si nanostructure. This mechanism is explained as “optical doping” of a semiconductor and develops in a manner peculiar to semiconductor nanostructures. Fiz. Tekh. Poluprovodn. 32, 613–619 (May 1998)