Biomedical subjects

A Baumann

Publications and source records attributed to A Baumann.

At least 19 recordsLinked to original sources

PubMed2003

[Rupture of internal iliac artery aneurysm -- a rare cause of life-threatening rectal bleeding].

Isolated aneurysms of the iliac arteries are rare. Located deep in the lesser pelvis, they are diagnosed late or in a symptomatic stage. Because of their manifold anatomic relationships to pelvic structures, iliac aneurysms may cause different symptoms such as obstipation, hydronephrosis, venous thrombosis, and entrapment neuropathy. Aneurysm rupture is associated with high mortality. The rupture of an iliac aneurysm into the rectum with massive lower intestinal bleeding is extremely rare. We report a patient with 6-year follow-up after aneurysm resection, extra-anatomic bypass, and suture repair of the rectum with temporary colostomy.

Aged↗

PubMed2003

Follow-up study of treatment of orbital floor fractures: relation of clinical data and software-based CT-analysis.

This retrospective study quantifies isolated orbital floor fractures using software-based CT-analysis and compares the clinical outcome across surgical and non-surgical treatment groups. Depending on the surgeon's interpretation of the clinical and radiological appearance, 10 fractures were treated non-surgically and 20 fractures surgically, either with antral balloon catheter alone or in combination with an orbital implant. Ophthalmologic findings were evaluated until 12 weeks after injury. Fracture area, and volume of displaced tissue (VDT) were assessed by software-based CT-analysis. VDT was marginally significantly smaller in non-surgically than in surgically-treated patients (P=0.08). Ophthalmologic findings improved in all groups during follow-up and no statistical difference was found between the groups. Diplopia remained moderate in three patients with balloon catheter alone, and minimal in four patients in both surgical groups. In one patient with non-surgical treatment, diplopia remained minimal after 12 weeks. Although CT-analysis revealed no significant difference between both surgical groups, patients treated with balloon catheter alone presented more diplopia after 12 weeks. Using balloon catheters for fracture repair a combined approach should be performed when large fractures involve the orbital floor to achieve sufficient reduction of orbital content and placement of an orbital implant. Software-based CT-analysis is helpful for objective interpretation in managing of orbital fractures.

Adult↗

PubMed2002

[Attitude of the population to schizophrenic patients in 6 federal German large cities].

In a research project of the German Research Network on Schizophrenia, public attitudes towards people with schizophrenia were studied within a public education project. In six German cities, 7,246 persons aged 16 or older were interviewed in a telephone survey. Knowledge of schizophrenia, social distance, and proposals for activities to improve the public acceptance of mentally ill persons were inquired. Most of the persons interviewed expressed positive attitudes towards people with schizophrenia. Better public education about mental illnesses and the opportunity for closer contact to mentally ill persons were rated as important to improve the public acceptance of these individuals.

Adolescent↗

PubMed2002

Public attitudes towards people with mental illness in six German cities: results of a public survey under special consideration of schizophrenia.

OBJECTIVES: Attitudes of the urban population in Germany towards people with mental illness were investigated in this study. The results are compared with those of attitude surveys conducted by other research centres participating in the World Psychiatric Association's (WPA) global anti-stigma-programme "Fighting Stigma and Discrimination because of Schizophrenia - Open the Doors" (WPA 1998). METHODS: A total of 7246 German-speaking persons aged 16 and over were interviewed in private households in six German cities by telephone using a standardised questionnaire. The respondents were asked about their knowledge in regard to schizophrenia, their social distance towards people with schizophrenia and estimations of the social stigmatisation of mental patients in general. RESULTS: 33.1 % of the interviewees were able to name causes of schizophrenia. 76.5 % of the interviewees believe that people with schizophrenia often or very often need prescription drugs to control their symptoms. 81.1 % believe that most people would pass over the job application of a former mental patient in favour of another applicant. CONCLUSIONS: Improvements in the education of the public about mental illnesses and provision of the opportunity for personal contact with mentally ill people are considered to be important measures for promoting the acceptance of the mentally ill by the public.

Adolescent↗

PubMed2002

Cell-extracellular matrix interaction and physico-chemical characteristics of titanium surfaces depend on the roughness of the material.

The interaction of cells with the extracellular matrix at the interface of an implant determines the biology of cells and tissues. We analysed components of cell adhesion and measured physico-chemical characteristics of structural modifications of titanium surfaces: polished, machined, glass particle-blasted, corundum-blasted, vacuum plasma-sprayed. Scanning electron microscopy and profilometry revealed a differentiated topography from smooth to rough surfaces, respectively. Osteoblastic MG-63 cells showed an increased spreading on surfaces with low roughness, although without a straight correlation with the surface topography. Integrin expression was increased on structured surfaces compared with polished material, and the organization of the actin cytoskeleton and fibronectin was impaired on extremely rough surfaces. Electrochemical methods, especially the electrochemical impedance spectroscopy (EIS) was used to evaluate physico-chemical characteristics, and the impedance curves revealed a dependence on the roughness of the material surfaces. Further analyses of the EIS results were performed using equivalent circuits which model the electrical flow through the interface. First indications for a correlation between parameters from the equivalent circuits with surface properties were obtained which promise a relevance for the biological response of the cells.

Actins↗

PubMed2002

Orbital floor reconstruction with an alloplastic resorbable polydioxanone sheet.

The orbital floor is frequently reconstructed after blow-out fractures or midface fractures to avoid a relapse of the repositioned orbital tissue and to prevent enophthalmos. A total of 31 patients underwent reconstruction of internal orbital wall fractures with a resorbable 0.25 mm or 0.5 mm-thick polydioxanone implant (PDS). Skeletal and functional outcome was evaluated retrospectively with regard to fracture size. Fracture size was graded as small, moderate or large by CT scans and operating records. Two of the 25 patients with small or moderate defects showed an enophthalmos of 2-3 mm. Five of the six patients with large defects or two orbital wall fractures had enophthalmos. The scar that formed after implant resorption was to weak to provide adequate support of the globe or to compensate the enlarged orbital volume. Endoscopic follow-up examination of 12 patients showed yielding of the scar in the orbital floor already in moderate defects. Eight patients had diplopia in extreme gaze and two had significant diplopia. Blow-out and midfacial fractures with small to moderate defects in the orbital floor (up to a size of 2.5 cm2) can be reconstructed by polydioxanone sheet to avoid enophthalmos. Polydioxanone implants should only be used in cases without massive orbital fat herniation. The scar formed after implant resorption may influence functional outcome.

Absorbable Implants↗

PubMed2001

Molecular and pharmacological properties of insect biogenic amine receptors: lessons from Drosophila melanogaster and Apis mellifera.

In the central nervous system (CNS) of both vertebrates and invertebrates, biogenic amines are important neuroactive molecules. Physiologically, they can act as neurotransmitters, neuromodulators, or neurohormones. Biogenic amines control and regulate various vital functions including circadian rhythms, endocrine secretion, cardiovascular control, emotions, as well as learning and memory. In insects, amines like dopamine, tyramine, octopamine, serotonin, and histamine exert their effects by binding to specific membrane proteins that primarily belong to the superfamily of G protein-coupled receptors. Especially in Drosophila melanogaster and Apis mellifera considerable progress has been achieved during the last few years towards the understanding of the functional role of these receptors and their intracellular signaling systems. In this review, the present knowledge on the biochemical, molecular, and pharmacological properties of biogenic amine receptors from Drosophila and Apis will be summarized. Arch.

Animals↗

PubMed2001

3D contrast-enhanced MR angiography of the run-off vessels: value of image subtraction.

The diagnostic gain associated with image subtractions was assessed regarding contrast-enhanced 3D magnetic resonance angiography (MRA) image sets of the pelvic and lower extremity arteries. The MRA strategy combined a dedicated vascular coil with a single injection, two-station protocol. Voxel-by-voxel signal intensity subtraction was performed on MRA image sets obtained before and during dynamic infusion of a para-magnetic contrast agent. Non-subtracted and subtracted MRA image sets were assessed for the presence of occlusive (four grades) disease, using DSA as the standard of reference. In addition, SNR and CNR were recorded for each vascular segment on both the non-subtracted and subtracted images. While CNR values of subtracted images exceeded those of non-subtracted images (P < 0.05), there was no difference in diagnostic performance. For the detection of hemodynamically significant disease, non-subtracted and subtracted MRA provided overall sensitivity and specificity of 90.2%/90.3% and 95.1%/95.6%, respectively. Concordance between non-subtracted and subtracted MRA was excellent (Kappa = 0.86).

Aged↗

PubMed2001

Forecasting models for human resources in health care.

This article is a review of the approaches published between 1996 and 1999 that have been used to forecast human resource requirements for nursing. Much of the work to date generally does not consider the complex factors that influence health human resources (HHR). They also do not consider the effect of HHR decisions on population health, provider outcomes such as stress, and the cost of a decision made. Supply and demand approaches have dominated. Forecasting is limited, too, by the availability of reliable and valid data bases for examining supply and use of nursing personnel across sectors. Three models--needs based, utilization based, and effective demand based--provide substantially different estimates of future HHR need. The methods of analysis employed for forecasting range from descriptive to predictive and are borrowed from demography, epidemiology, economics, and industrial engineering. Simulation models offer the most promise for the future. The forecasting methods described have demonstrated their accuracy and usefulness for specific situations, but none has proven accurate for long-term forecasting or for estimating needs for large geographical areas or populations.

Forecasting↗

PubMed2001

Use of the preseptal transconjunctival approach in orbit reconstruction surgery.

PURPOSE: This report evaluated the advantages of the preseptal transconjunctival approach in reconstruction of the orbit. PATIENTS AND METHODS: Ninety-nine preseptal incisions were used in 80 patients for different indications (blowout fracture, complex zygoma fracture, enophthalmos correction, midface hypoplasia, secondary incision). All operative procedures were performed without an additional lateral canthotomy. The infraorbital rim was stabilized with miniplates or microplates. RESULTS: There was no ectropion or entropion in any patients. Complications included 1 laceration of the tarsal plate and 1 temporary entropion after a primary subciliary incision. The overall complication rate was 2%. CONCLUSIONS: The preseptal transconjunctival incision without lateral canthotomy provides good exposure of the orbital floor and the caudal parts of the lateral and medial wall. This approach is preferable to a retroseptal approach in reconstructive orbital surgery because of minimal disturbance of the intraorbital connective tissue framework. The anatomic optimal dissection line also results in a lower complication rate.

Adolescent↗

PubMed2001

A computer-based method for calculation of orbital floor fractures from coronal computed tomography scans.

PURPOSE: A computer program recently developed for the calculation of the orbital floor and fracture areas from coronal computed tomography (CT) scans was used in a study to evaluate the accuracy and ability of this new method. MATERIAL AND METHODS: The size of orbital floors and fabricated fractures in 14 dried, anatomic specimens were measured in coronal CT scans by 3 independent observers. Based on this data set, the orbital floor and fracture regions were calculated with the newly developed computer program. These calculated regions were then compared with a direct measurement of the specimens that had been obtained by digital photography. The accuracy of the computer-based calculations was assessed using Lin's concordance correlation coefficient. RESULTS: The size of the orbital floor (mean +/- SD) was found to be 5.21 +/- 0.39 cm(2) by direct measurement of the specimens and 5.30 +/- 0.52 cm(2) by calculation with the computer program. The region of the fracture (mean +/- SD) was 1.05 +/- 0.64 cm(2) by direct measurement and 1.01 +/- 0.62 cm(2) by computer calculation. The between-method mean difference (direct measurement minus computer based calculation) was -0.09 cm(2) (or 1.7% of mean orbital floor region) for orbital floor region and 0.04 cm(2) (or 3.8% of mean fracture region) for fracture region. CONCLUSIONS: This accurate and time-saving method is practicable for determining the size and location of orbital floor fractures. This calculation program can be advantageously applied in the clinical management of blowout fractures of the orbit.

Algorithms↗

PubMed2001

Midfacial degloving: an alternative approach for traumatic corrections in the midface.

Midfacial degloving was used as an approach in 14 patients to correct post-traumatic deformities in the midface. In eight patients, deformities in the naso-orbito-ethmoid region were corrected by orbitonasal osteotomy, telecanthus correction, orbital grafting and nasal augmentation procedures. Zygomatic osteotomies were performed in five patients with orbitozygomatic deformity. In one patient, a midface fracture (Le Fort II/III) was reconstructed after midfacial degloving. By combination of transoral vestibular, intranasal and preseptal transconjunctival incisions a complete degloving of the midface up to the nasofrontal angle and the zygoma prominence was possible. All osteotomies could be completed after midfacial degloving. Additional coronal incisions were not required. Orbitonasal osteotomies for nasal lengthening as well as fixation of the medial canthal ligament by a miniplate could be performed under direct vision. There were no postoperative complications such as stenosis of the nasal aperture or disturbances of the mimic musculature. Midfacial degloving offers good exposure, specially of the central part of the midface, without leaving an external scar. It is useful for reconstructive procedures in patients after midface trauma.

Adult↗

PubMed2001

Reperfusion of autotransplanted teeth--comparison of clinical measurements by means of dental magnetic resonance imaging.

OBJECTIVE: Dental magnetic resonance imaging (dMRI) with administration of contrast material is one method of assessing pulpal perfusion. The purpose of this study was to evaluate the level of contrast enhancement displayed by means of dMRI after transplantation of teeth and to compare these findings with the results of tooth mobility, pocket depth, cold, and electrical tests. STUDY DESIGN: Twenty-three teeth with either complete root formation or incomplete root formation (IRF) were investigated by using dMRI and were clinically examined at intervals of 2, 4, 8, and 12 weeks, as well as 6 months and 12 months after transplantation. RESULTS: An analysis of the enhancement in the dental images revealed a significant difference between teeth with IRF and teeth with complete root formation. In addition, the time to occurrence of a positive reaction to the cold test was significantly longer for teeth with IRF. CONCLUSIONS: The findings of this study indicate that transplanted IRF teeth are associated with reperfusion seen by means of dMRI as well as with delayed occurrence of a positive cold test.

Adolescent↗

PubMed2001

Nurses' experiences of restructuring in three Ontario hospitals.

PURPOSE: To describe the effects of restructuring, particularly redeployment, on nurses' personal and work lives, and to compare the utility of "survivor syndrome" and empowerment as alternative concepts for understanding these effects and planning change. METHODS: Twenty-six focus groups or interviews were held with 59 nurses working in three hospitals in Ontario, Canada. FINDINGS: Participants described how restructuring strategies had affected them as individuals, as members of nursing teams, and as employees. In each of these aspects of their work lives, relationships became less integrated, their work activities became less controllable, and the changes compromised their ability to deliver effective care. CONCLUSIONS: Restructuring intensifies structural weaknesses in professions, such as nursing, whose members are primarily employed by bureaucracies. Nurses may not find survivor syndrome a useful model to explain their low morale following restructuring because it identifies nurses as "patients" in need of therapy. An empowerment model that takes into account nurses' concerns about uncertainty and integration may be more fruitful for devising strategies to enhance their ability to practice effectively in hospital settings.

Adaptation, Psychological↗

PubMed2000

The use of marine molluskan shells for Roman glass and local raw glass production in the Eifel area (western Germany).

Relatively high strontium concentrations and their isotopic composition in Roman glass of the Imperial period indicate the general use of shells as carbonate raw material. Lead, iron, and barium concentrations and lead isotopes of glass of the late fourth century from Hambach and Gellep (western Germany) are conformable with the use of glass sand from Eifel rivers. Each of three pairs of six simultaneously operating Roman glasshouses in the Hambach area made its own raw glass from different quartz sands.

Animals↗

PubMed2000

Application of the buccal fat pad in oral reconstruction.

PURPOSE: This report evaluates the use of the buccal fat pad in reconstruction of defects of the hard and soft palate. PATIENTS AND METHODS: Twenty-nine patients with different indications (oroantral fistula, tumor of the hard and soft palate, posterior fistula in cleft patients, covering of bone transplants in augmentation procedure) were treated with a pedicled buccal fat pad without lining. The maximum reconstructed defect was 5.5 x 4 cm. RESULTS: All inserted fat grafts healed well without any aesthetic disturbances. The surface of the fat converted to normal mucosa. CONCLUSIONS: Use of the buccal fat pad is a safe and easy method to reconstruct defects in the posterior maxilla and soft palate. Good vascularization, ease of access, and minimal donor site morbidity make it a reliable soft tissue graft.

Adipose Tissue↗

PubMed2000

Amtyr1: characterization of a gene from honeybee (Apis mellifera) brain encoding a functional tyramine receptor.

Biogenic amine receptors are involved in the regulation and modulation of various physiological and behavioral processes in both vertebrates and invertebrates. We have cloned a member of this gene family from the CNS of the honeybee, Apis mellifera. The deduced amino acid sequence is homologous to tyramine receptors cloned from Locusta migratoria and Drosophila melanogaster as well as to an octopamine receptor cloned from Heliothis virescens. Functional properties of the honeybee receptor were studied in stably transfected human embryonic kidney 293 cells. Tyramine reduced forskolin-induced cyclic AMP production in a dose-dependent manner with an EC50 of approximately 130 nM. A similar effect of tyramine was observed in membrane homogenates of honeybee brains. Octopamine also reduced cyclic AMP production in the transfected cell line but was both less potent (EC50 of approximately 3 microM) and less efficacious than tyramine. Receptor-encoding mRNA has a wide-spread distribution in the brain and subesophageal ganglion of the honeybee, suggesting that this tyramine receptor is involved in sensory signal processing as well as in higher-order brain functions.

Amino Acid Sequence↗

PubMed2000

In vitro model of the human liver parenchyma to study hepatotoxic side effects by Dy-EOB-DTPA.

RATIONALE AND OBJECTIVES: In vivo studies have shown species-specific toxicity after application of the liver-specific contrast agent Dy-ethoxybenzyl (EOB)-DTPA. To predict species differences in the laboratory, an in vitro model of the liver was used to examine the divergent results. METHODS: Rat, canine, porcine, and human hepatocytes were isolated and embedded between layers of collagen. During and after 48 hours of incubation with different concentrations of Dy-EOB-DTPA (maximum concentration 50 mmol/L), morphological changes and enzyme leakage were determined. RESULTS: The response to the contrast agent varied for hepatocytes from different species. For canine cells, morphological changes and cell death were evident with as little as 5 mmol/L Dy-EOB-DTPA. Rat hepatocytes tolerated up to 50 mmol/L Dy-EOB-DTPA, and enzyme leakage was transient. Only after incubation with 50 mmol/L Dy-EOB-DTPA was the formation of intracellular vacuoles evident. In contrast, even the highest concentration of Dy-EOB-DTPA did not cause an enzyme leakage of porcine or human hepatocytes, although similar vacuoles were seen. CONCLUSIONS: These data demonstrate a species-dependent toxicity for Dy-EOB-DTPA in vitro, with similar responses in porcine and human hepatocytes.

Animals↗