3D printed simulation models based on real patient situations for hands-on practice.

During the last few years, the curriculum of many dentistry schools in Germany has been reorganised. Two key aspects of the applied changes are the integration of up-to-date teaching methods and the promotion of interdisciplinarity. To support these efforts, an approach to fabricating individualised simulation models for hands-on courses employing 3D printing is presented. The models are based on real patients, thus providing students a more realistic preparation for real clinical situations. As a wide variety of dental procedures can be implemented, the simulation models can also contribute to a more interdisciplinary dental education. The data used for the construction of the models were acquired by 3D surface scanning. The data were further processed with 3D modelling software. Afterwards, the models were fabricated by 3D printing with the PolyJet technique. Three models serve as examples: a prosthodontic model for training veneer preparation, a conservative model for practicing dental bonding and an interdisciplinary model featuring carious teeth and an insufficient crown. The third model was evaluated in a hands-on course with 22 fourth-year dental students. The students answered a questionnaire and gave their personal opinion. Whilst the concept of the model received very positive feedback, some aspects of the implementation were criticised. We discuss these observations and suggest ways for further improvement.

Iron(II) spin-crossover complexes in ultrathin films: electronic structure and spin-state switching by visible and vacuum-UV light.

The electronic structure of the iron(II) spin crossover complex [Fe(H2bpz)2(phen)] deposited as an ultrathin film on Au(111) is determined by means of UV-photoelectron spectroscopy (UPS) in the high-spin and in the low-spin state. This also allows monitoring the thermal as well as photoinduced spin transition in this system. Moreover, the complex is excited to the metastable high-spin state by irradiation with vacuum-UV light. Relaxation rates after photoexcitation are determined as a function of temperature. They exhibit a transition from thermally activated to tunneling behavior and are two orders of magnitude higher than in the bulk material.

Efficacy of surgery for internal snapping hip.

Our purpose was to evaluate evidence regarding the effectiveness of open iliopsoas release and lengthening with arthroscopic approaches, which combine iliopsoas release with the treatment of intra-articular pathology as treatments for internal snapping hip syndrome. Searches were performed of 4 databases and 12 reports on the surgical treatment of internal snapping hip were reviewed. The authors tabulated data according to year of study, journal, study type, level of evidence, patient demographics, procedure, and outcomes. We found that surgical treatment of internal snapping hip improves patient symptoms in the majority of patients. Endoscopic release is associated with fewer reported complications compared with open release. All studies of endoscopic treatment of internal snapping hip syndrome also performed intra-articular examination and treatment of intra-articular pathology. The incidence of associated intra-articular pathology was reported in 5 of 6 studies. These results suggest that a painful snapping iliopsoas tendon in many cases may be a result of intra-articular hip pathology rather than an independent entity. Early studies suggest no difference in efficacy or associated complications rate when comparing extracapsular to transcapsular iliopsoas tendon release. Further studies are needed comparing operative to nonoperative treatment and methods of determining patients likely to benefit from operative intervention.

Effects of electric and magnetic fields from high-power lines on female urinary excretion of 6-sulfatoxymelatonin.

In 1998, the authors studied the effect of residential exposure to electric and magnetic fields from high-power lines on female urinary excretion of 6-sulfatoxymelatonin (6-OHMS) in the Quebec city, Canada, metropolitan area. A sample of 221 women living near a 735-kV line was compared with 195 women the same age living away from any power lines. Participants provided morning urine samples on 2 consecutive days and wore a magnetic dosimeter for 36 consecutive hours to measure personal magnetic exposure. The indoor electric field was assessed by spot measurements. After adjustment for other factors associated with low melatonin secretion, such as medication use or light exposure, nighttime concentration of 6-OHMS was similar in the two groups. When either 24-hour or sleep-time exposure to magnetic field or electric field measurements was used, no exposure-effect relation was evident. However, the trend of decreasing 6-OHMS concentration with age was more pronounced for women living near the lines, as was a lower 6-OHMS concentration in women with high body mass index. Chronic residential exposure to magnetic fields from high-power lines may accentuate the decrease in melatonin secretion observed in some vulnerable subgroups of the population.

Billing for cognitive services: understanding Québec pharmacists' behavior.

BACKGROUND: There is growing evidence that pharmacists' interventions to solve drug-related problems are effective and cost-saving. Since 1978, under the Quebec provincial drug plan, payment for two cognitive services, the pharmaceutical opinion and the refusal to dispense a prescription, has been disbursed to community pharmacists. However, the number of claims for these services lags far behind expectations. OBJECTIVE: To identify factors influencing Quebec community pharmacists in the billing for a pharmaceutical opinion or for a refusal to dispense. METHODS: Questions on predisposing, enabling, and reinforcing factors potentially related to pharmacists' behavior were included in a self-administered questionnaire sent to all 3517 community pharmacists practicing in the province of Quebec during 1996. Using multivariate logistic regression, models were built to explain billing for an opinion and billing for a refusal. RESULTS: According to our models, the typical pharmacist who billed for opinions or refusals in Quebec is <45 years of age, has attended a continuing education program on this topic, and believes that billing for interventions is important. This typical pharmacist handles a mean daily volume of 100-250 prescriptions, uses a decision-support computer program, and has sufficient technical staff assistance. This pharmacist believes that interventions can be billed rapidly and are consistently paid by the province's drug plan. CONCLUSIONS: In order to increase the billing of pharmaceutical care in community pharmacies, tailored educational programs should be offered to pharmacists. There is also a need to improve working conditions in pharmacies.

Sarcoidosis: unusual cause of a rectal mass.

We have reported the case of a patient who had a rectal mass 3 years after the diagnosis of sarcoidosis. A malignancy was suspected, but biopsy of the rectal mass showed epithelioid granulomas with giant cells, consistent with sarcoidosis. Therefore, sarcoidosis should be considered as a rare cause of a rectal mass.

[The AIDS qualification program of the federal government--a orienting approach for improving the performance of the public health service]. / Das AIDS-Qualifizierungsprogramm der Bundesregierung--ein richtungweisender Ansatz zur Verbesserung der Leistungsfähigkeit des öffentlichen Gesundheitsdienstes.

The AIDS Control Programme of the Federal Government is the first national programme in the Federal Republic of Germany, trying to prevent the spread of a specific disease on a broader scale. The question is raised whether the present highly legally orientated Public Health services in the Federal Republic of Germany meet the real health needs of the population. The author also calls for a more policy-orientated Public Health care by the physicians in Public Health services.

Biokinetics of bone tracers by means of deconvolution analysis--comparison of 99mTc MDP, 99mTc DPD and 99mTc EHDP.

Transfer functions of 99mTc methylene diphosphonate (MDP), 99mTc 2,3-dicarboxypropane-1,1-diphosphonate (DPD) and 99mTc ethane-1-hydroxy-1,1-diphosphonate (EHDP) into bone and extravascular fluid of soft tissues were determined in 5 dogs by deconvolution analysis of the time-course of plasma, soft tissue and bone radioactivity. The transfer rates 5 min after injection--indicating the rapid exchange of the tracer between plasma and the extravascular fluid--decrease in the order MDP greater than EHDP greater than DPD (P less than 0.05). The transfer rates into bone--determined from transfer rates between 30 and 60 min--decreased in a different order, i.e. MDP greater than DPD greater than EHDP (P less than 0.05). The fractional bone uptake of diphosphonates estimated from the ratio of early to late transfer rates was slightly greater for DPD than for MDP and EHDP respectively. The difference between DPD and MDP was not significant (P greater than 0.05). The average bone and soft tissue concentrations of DPD 60 min after injection were greater than that of MDP and EHDP due to different plasma concentrations (DPD greater than EHDP greater than MDP), whereas the bone-to-soft tissue ratios decreased in the sequence MDP greater than DPD greater than EHDP (P less than 0.05).--Our results reveal different biokinetics of MDP, DPD and EHDP explaining variations in osseous and soft tissue uptake suggesting that deconvolution analysis could play an important role in bone scan interpretation.

[Observation of the course of 4-year ambulatory peritoneal dialysis in the treatment of chronic uremia]. / Verlaufsbeobachtung einer 4 jährigen ambulanten Peritonealdialyse zur Behandlung der chronischen Urämie.

It is reported on a 4-year chronic peritoneal dialysis due to decompensated retention of substances normally contained in the urine in chronic pyelonephritis. Under a treatment regimen of 3.6 dialyses with 20 1 of wash each satisfying values of creatinine, haemoglobin and total protein in the serum were found. Further a vast normalisation of the blood pressure could be achieved. A series of complications partly repeatedly appearing could be treated successfully. By a diet rich in protein and careful use of the peritoneal dialysis catheter the most dangerous complications of the peritoneal dialysis, loss of protein and peritonitis, did not represent a serious problem.

[Scintigraphy of liver after combined chemo-/immunotherapy with malignant melanoma (author's transl)]. / Leberzintigraphische Veränderungen nach kombinierter Chemo-/Immunotherapie beim malignen Melanom.

Thirty patients with malignant melanoma received combined chemo-/immunotherapy with Dacarbazine and BCG after operation. Before therapy and 6-10 weeks after the liver was examined by clinical, laboratory and scintigraphic means. We wanted to find out the side effects of the therapy on liver and the use of the gated scintigraphy to diagnose liver parenchymal changes. Each of the patients had normal laboratory results as well as a normal scintigraphy before therapy. After chemotherapy 19 patients had a pathological liver scintigram. Also specific liver enzymes were elevated. While 12 patients showed a diffuse, inhomogeneous liver pattern with scintigraphy, 5 patients had an additional diffuse liver increase on top. Four patients also showed signs of intrahepatic cholestasis. In 11 patients the result was unsignificant. Related to the liver toxicity of Dacarbazine, liver scintigraphy is able to detect a liver reaction at a point where laboratory and clinical signs don't give a significant information.

Deconvolution analysis of 99mTc-methylene diphosphonate kinetics in metabolic bone disease.

The kinetics of 99mTc-methylene diphosphonate (MDP) and 47Ca were studied in three patients with osteoporosis, three patients with hyperparathyroidism, and two patients with osteomalacia. The activities of 99mTc-MDP were recorded in the lumbar spine, paravertebral soft tissues, and in venous blood samples for 1 h after injection. The results were submitted to deconvolution analysis to determine regional bone accumulation rates. 47Ca kinetics were analysed by a linear two-compartment model quantitating short-term mineral exchange, exchangeable bone calcium, and calcium accretion. The 99mTc-MDP accumulation rates were small in osteoporosis, greater in hyperparathyroidism, and greatest in osteomalacia. No correlations were obtained between 99mTc-MDP bone accumulation rates and the results of 47Ca kinetics. However, there was a significant relationship between the level of serum alkaline phosphatase and bone accumulation rates (R = 0.71, P less than 0.025). As a result deconvolution analysis of regional 99mTc-MDP kinetics in dynamic bone scans might be useful to quantitate osseous tracer accumulation in metabolic bone disease. The lack of correlation between the results of 99mTc-MDP kinetics and 47Ca kinetics might suggest a preferential binding of 99mTc-MDP to the organic matrix of the bone, as has been suggested by other authors on the basis of experimental and clinical investigations.

[Functional imaging of characteristic kinetic parameters of kidney and thyroid (author's transl)]. / Darstellung charakteristischer Parameter der Tracerkinetik von Niere und Schilddrüse in Funktionsbildern.

A procedure has been developed by which the reaction of an organ to a very short delta-function activity pulse of an organ-specific tracer introduced into the blood can be determined for the kidney and the thyroid. The data for the procedure are available from sequence scintigrams and the change with time of the activity of the tracer in the blood. The nature and duration of this reponse function makes it possible to calculate organ-specific parameters such as uptake rates, clearance rates or transit times. They may be calculated for the total field of the gamma camera and delineated as grey or colour gradations to yield the respective parametric functional images. The apparatus necessary for the procedure is described and its possible clinical application in comparison to conventional scintigraphic procedure is discussed.

[Therapy of primary glomerulonephritis. Comparative study on the effect of cytostatics-prednisone and cytostatics-anticoagulant-aggregation inhibitor combination]. / Therapie der primären Glomerulonephritis--Vergleichende Studie über den Einfluss einer Zytostatika-Prednison- und einer Zytostatika-Antikoagulantien-Aggregationshemmer-Kombination.

The result of the treatment with chlorambucil, dipyridamol, heparin/warfarin and prednisone on 50 patients as well as with imuran and prednisone on 32 patients is compared. Basis for this is a detailed morphological and clinical subdivision. With the help of therapy results is tried to derive regions of indication: the therapy with cytostatics, anticoagulants and aggregation inhibitors is above all suitable for patients with a short duration of the disease and with sign of activity, also in renal insufficiency. On the other hand the therapy with cytostatics and prednisone is also successful in patients with longer duration of the disease and missing signs of activity.

[Treatment of glomerulonephritis]. / Zur Therapie der Glomerulonephritis.

The therapeutic effect of the prednisone therapy, of the short-time (duration of treatment 2-4 months) and of the long-term (duration of treatment 1.5 to 2 years) imuran and prednisone therapy was investigated on 218 patients with chronic, functionally compensated glomerulonephritis. The importance of the urine symptomatology for the control of the therapeutic success and for the prognosis of the disease was elaborated. Corresponding to the clinical picture the experiment of a clinical classification of the chronic glomerulonephritis was performed.

[Reversible myocardial ischaemia or irreversible myocardial fibrosis? Differentiation by biphasic 201thallium scintigraphy (author's transl)]. / Reversible Myokardischämie oder irreversible Myokardfibrose? Unterscheidung mit Hilfe der biphasischen 201-Thallium-Szintigraphie.

The results of biphasic 201thallium (201Tl) scanning were compared with those of coronary arteriography, left ventricular angiogarphy and stress ECG in 56 patients with coronary artery disease and six with no evidence of heart disease. There were 104 201Tl defects, 50 of them reversible. The defects were always located in the area supplied by a critically stenotic coronary artery. Correlation of regional wall motion with 201Tl activity demonstrated that in all forms of abnormal wall motion there was either ischaemia or fibrosis. The resting LV angiogram thus does not make it possible to distinguish between myocardial ischaemia and fibrosis. Taking the LV angiogram as a standard, the rate of false-positive 201Tl scintigrams was 5%, that of false-negative ones 23%. The biphasic 201Tl scintigram was more sensitive than the stress ECG in detecting myocardial ischaemia. It furthermore made it possible to localize the ischaemic (or fibrotic) region within the LV and to estimate its size.