APCI/APPI for synthetic polymer analysis.

Modern mass spectrometry of synthetic polymers involves soft ionization techniques. Whereas matrix-assisted laser desorption/ionization (MALDI) and electrospray (ESI) are employed routinely, atmospheric pressure chemical ionization (APCI) and more recently atmospheric pressure photoionization (APPI) are used to a lesser extent. However, these latter ionization methods coupled to liquid-phase separation techniques create new opportunities for the characterization of polymers, especially for low molecular weight compounds or for the polymers that are poorly ionizable by the usual methods. After a part devoted to the description of classical MS methods employed for polymer analysis (MALDI, ESI, and their use with chromatography), APCI and APPI techniques will be described, discussed, and selected examples will present the interest of these ionization sources (or interfaces for LC/MS) in the field of polymer analysis.

Hyphenation of surface plasmon resonance imaging to matrix-assisted laser desorption ionization mass spectrometry by on-chip mass spectrometry and tandem mass spectrometry analysis.

Most of the recent developments aiming to the coupling between surface plasmon resonance (SPR) and mass spectrometry (MS) are based on the use of a biochip with a limited number of flow cells requiring elution steps for the recovery of the captured biomolecules. In this work, a direct on-chip MALDI-MS detection is presented using a SPRi-sensor biochip in a microarray format that allows a multiplex SPR-MS analysis. The biochip gold surface was functionalized by a self-assembled monolayer (SAM) of short polyoxyethylene (POE) chains carrying a N-hydroxysuccinimide (NHS) group for the immobilization of biomolecules. The SPR measurement of the interaction of grafted antibodies anti-beta-lactoglobulin and anti-ovalbumin with their corresponding antigens indicated that the POE-NHS SAM preserved the binding activity of the antibodies immobilized on the biochips surface. SPR-MS experiments were carried out through MALDI-MS detection of the retained antigens (beta-lactoglobulin and ovalbumin) directly from the biochip surface. Mass spectra were obtained from each distinct spot on the arrayed biochips. Femtomole amounts of specifically retained antigen proteins as determined by SPR were sufficient to obtain good quality mass spectra. These mass spectra showed protein ions corresponding to the specific antigen, without any trace of nonspecific binding. The underivatized portion of the chip was also devoid of nonspecifically bound proteins, indicating that the functionalization of the biochips surface by short polyoxyethylene chains greatly minimizes the unspecific binding. In addition, it allowed on-chip digestion of the specifically bound analyte and coupling with MS/MS experiments, opening numerous applications in the proteomic field.

Studies of sequence-specific recognition and interaction of bishairpin polyamide minor groove binders with target DNA duplexes.

The binding of bis-MGB to target DNA was studied by DNase footprint, native gel shift, circular dichroism, thermal dissociation, electrospray mass-spectrometry, and molecular modelling methods. A new method for the determination of the relative affinity of ligands against various dsDNA sequences was elaborated by using ESI-QTOF mass spectrometry. Information about affinity, sequence preferences, conformation and mode of interaction between bis-MGB and target DNA was obtained. Our experiments demonstrated that MGB have different affinity for similar cognate target sequences depending on the sequence context of the target region and other structural factors.

Adherence: a matter of self-efficacy and power.

This paper examines the relationship between self-efficacy and social power (expert and referent) and how the application of this relationship, leads to client adherence and compliance. Referent power is defined, including methods that health care professionals may use to develop and apply referent power. Expert power is defined and addressed in the context of referent power, self-esteem and self-efficacy as a means of promoting adherence. Self-efficacy as a concept is defined and explored in the context of social power. The relationships between self-efficacy and social power (expert and referent) are shown as important determinants of adherence and compliance. The theory of the application of referent and expert power in relationship with self-efficacy has been compared with an effective programme, yielding high compliance, at Western Psychiatric Institute and Clinic, showing the theory's relevance and applicability in determining compliance. Explored are the reasons for non-compliance in the elderly population and how the theory model can remedy these detriments for compliance. The empowerment of elderly patients through the application of this theory to medication compliance is examined. The determination of adherence and compliance is shown by the application of the relationship between self-efficacy and both expert and referent power.

[The assessment of the caries risk in young adults]. / Zur Einschätzung des Kariesrisikos bei jungen Erwachsenen.

Several factors for caries prediction have been proved in a one-year follow-up study on 73 patients. The white-spot lesions have proved to be a good criteria for caries prediction in this population. These lesions could be combined with the microbiological tests Dentocult SM and Oricult N or with the determination of the buffer capacity (Dentobuff), which did not much improve the prediction.

[Incidence of bone tumors in the facial skeletal area]. / Zur Häufigkeit von Knochentumoren im Bereich des Gesichtsschädels.

Facial bone tumors seen at a specialized referral unit over the course of a decade were retrospectively reviewed. Case definitions and statistical analysis were performed in accord with the criteria established by the National Bone Tumor Registry. Two-thirds of the 110 histologically confirmed bone tumors of this region occurred in female patients. The average age at onset was 39 years. Tumor-like processes predominated (56.4%). Peripheral giant cell granulomas were the most frequent lesions followed by odontogenic tumors (19%), principally odontomas. Benign bone tumors contributed 15.4%. The least frequently represented types of facial bone tumors were primary and secondary malignancies.