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Biomedical subjects

Barbara Heller

Publications and source records attributed to Barbara Heller.

7 recordsLinked to original sources
PubMed2007

Phosphorus-bearing axially chiral biaryls by catalytic asymmetric cross-cyclotrimerization and a first application in asymmetric hydrosilylation.

A novel and efficient, two-step route to axially chiral biaryls is demonstrated. In a direct asymmetric cross-cyclotrimerization in the presence of a chiral cobalt(I) catalyst, axially chiral biaryls bearing phosphoryl moieties have been prepared, and through indirect evidence the authors have been able to clarify the origin of the stereochemical induction and the nature of the central intermediate in the catalytic cycle. By subsequent reduction of the phosphoryl moiety to the corresponding phosphine, a very efficient and atom-economical approach to chiral systems has been developed. These chiral systems clearly have great potential use as axially chiral monodentate P- or bidentate P,O-ligands, as has been demonstrated by the employment of the novel NAPHEP as a new monodentate acting ligand in an asymmetric hydrosilylation reaction.

Journal Article↗
PubMed2004

Oxaprozin versus diclofenac in NSAID-refractory periarthritis pain of the shoulder.

OBJECTIVE: To evaluate the efficacy and safety of oxaprozin in comparison with diclofenac in patients with periarthritis pain of the shoulder previously unsuccessfully treated with nonsteroidal anti-inflammatory drugs other than diclofenac and oxaprozin. METHODS: In this open, multicentre, randomised, controlled study, eligible patients with periarthritis of the shoulder were randomised to receive either oxaprozin 1200 mg once daily (n = 49) or diclofenac 50 mg three times daily (n = 47). The treatment period was 15 +/- 1 days. The study was planned on a hypothesis of equivalence between the two study drugs. The primary study endpoint was the change from baseline at day 15 in the patient-assessed shoulder pain score. Secondary efficacy variables included investigator-assessed shoulder function, patient-assessed quality of life on the Short-Form-36 (SF-36) Acute Health Survey and both patients' and investigators' overall assessment of efficacy. RESULTS: At day 15, the mean changes in shoulder pain score from baseline in the oxaprozin and diclofenac groups were -5.85 +/- SD 4.62 and -5.54 +/- SD 4.41, respectively. The difference between the two groups was not statistically significant, confirming the hypothesis of the study that oxaprozin is as effective as diclofenac. Investigator-assessed shoulder function improved in both groups but more so in the oxaprozin group (p = 0.028 at day 15). Quality of life as measured by SF-36 total score was also improved in both treatment groups, with a trend toward greater improvement in the oxaprozin group. Furthermore, a significantly more favourable effect on the SF-36 'mental health' item was observed in oxaprozin compared with diclofenac-treated patients at day 15 (p = 0.0202). As assessed by investigators, the overall efficacy of oxaprozin was superior to that for diclofenac at visit 3 (8 +/- 1 days) (p = 0.0067). Patients also assessed the overall efficacy of oxaprozin as superior to that of diclofenac at visits 3 (8 +/- 1 days) (p = 0.0235) and 4 (15 +/- 1 days) (p = 0.0272). Only six adverse events, all of which were mild or moderate in intensity and occurred in four diclofenac recipients, were observed in the study. CONCLUSIONS: As expected, once-daily oxaprozin proved to be as effective as diclofenac three times daily in reducing the primary efficacy variable of patient-assessed shoulder pain score in patients with periarthritis of the shoulder refractory to previous treatments with other NSAIDs. Oxaprozin was shown to be superior to diclofenac in improving shoulder function and was considered by investigators and patients to have greater overall efficacy than diclofenac. In addition, oxaprozin showed a trend toward superior results in improving patients' quality of life compared with diclofenac. A trend towards better tolerability results for oxaprozin compared with diclofenac was also noted.

Anti-Inflammatory Agents, Non-Steroidal↗
PubMed2004

Adaptive guideline-based treatment workflows with AdaptFlow.

One goal in modern medicine is to increase the treatment quality. A major step towards this aim is to support the execution of standardized, guideline-based clinical protocols, which are used in many medical domains, e.g., for oncological chemotherapies. Standardized chemotherapy protocols contain detailed and structured therapy plans describing the single therapy steps (e.g., examinations or drug applications). Therefore, workflow management systems offer good support for these processes. However, the treatment of a particular patient often requires modifications due to unexpected infections, toxicities, or social factors. The modifications are described in the treatment protocol but not as part of the standard process. To be able to further execute the therapy workflows in case of exceptions running workflows have to be adapted dynamically. Furthermore, the physician should be supported by automated exception detection and decision support for derivation of necessary modifications. The AdaptFlow prototype offers the required support for the field of oncological chemotherapies by enhancing a workflow system with dynamic workflow adaptation and rule based decision support for exception detection and handling.

Clinical Protocols↗
PubMed2003

Facile and racemization-free conversion of chiral nitriles into pyridine derivatives.

The results described herein demonstrate how the very mild reaction conditions of the Co(I)-catalyzed photochemical [2 + 2 + 2] cyclocotrimerization are suited to prepare chiral compounds containing unsubstituted and polysubstituted 2-pyridyl moieties starting from chiral nitriles without any detectable loss of enantiomerical purity. This further increases the already very broad synthetic scope of this particular reaction.

Journal Article↗
PubMed2002

Photocatalyzed [2 + 2 + 2]-cycloaddition of nitriles with acetylene: an effective method for the synthesis of 2-pyridines under mild conditions.

The photocatalyzed [2 + 2 + 2]-cycloaddition of nitriles with 2 equiv of acetylene to 2-pyridines can be carried out under mild conditions and represents a valuable extension to common synthetical methods. For the ideal wavelength range (350-500 nm), lamps as well as sunlight can be used. Working at room temperature and in organic solvents such as toluene or hexane as well as in water gives satisfying results in many cases. However, it is also possible to vary the solvent and the reaction temperature of the photocatalyzed synthesis and to choose, with respect to the specific substrate, specific requirements for this particular reaction and general requirements of the method. This simple and selective method derives its potential mainly from the large variety of applicable nitriles. Suitable substrates include (functionalized) aliphatic and aromatic nitriles as well as cyanamides derived from secondary amines.

Journal Article↗