bluuebunny/crossref_metadata_2025 huggingface dataset:
Effectiveness of an oral health education programme in primary schools in Zimbabwe after 3.5 years
Authors: Frencken Jo E. , Borsum‐Andersson Karin , Makoni Fiona , Moyana Farayi , Mwashaenyi Shadreck , Mulder Jan
Published: March 2003

Abstract – Many medical and dental professionals in African nations believe that school teachers, through attendance of a short workshop, can be trained to provide oral health education. This increases the number of professionals available and is regarded as an important way forward in improving oral health. Objectives: The current study assesses the effectiveness of an oral health education programme administered by schoolteachers in a district in Zimbabwe over a period of 3.5 years. Methods: The experimental group consisted of schools that had sent representatives to a regional workshop on oral health held in 1992. The control group was selected at random from schools not having attended the workshop. A total number of 439 boys and 526 girls were examined in 1992. Follow‐up evaluations were carried out in 1993, 1994 and 1996. The dependent variables were plaque accumulation and caries increment in grade 2 and grade 4 children of experimental and control schools. Results: ANOVA test with year of evaluation (1992–94), experiment/control school, age and gender as independent variables showed no statistically significant difference in mean plaque scores in longitudinally examined original grade 2 (P>0.20) and grade 4 children (P=0.06) from experimental and control schools. The mean caries increment score in the experimental and control schools was 0.04 and 0.19, respectively. ANOVA test with fluoride levels and gender as independent variables on caries increment in experimental and control schools did not show a statistically significant difference (P=0.06). Conclusion: The one‐time training of teachers in aspects of oral health was ineffective in lowering plaque levels over a period of 3.5 years. Considering the low caries increment observed over the study period, the effect of the oral health programme on caries levels in the study group was inconclusive.
Psychological disorders and dental anxiety in a young adult population
Authors: Locker D. , Poulton R. , Thomson W. M.
Published: March 2003

Abstract – Objectives: It has been suggested that some individuals who are fearful or anxious about dental treatment have a constitutional vulnerability to anxiety disorders as evidenced by the presence of multiple fears, generalized anxiety or panic disorders. This paper compares the prevalence of psychological disorders among dentally anxious and non‐anxious groups drawn from the general population. Methods: Data were obtained as part of a birth cohort study when study members were aged 18 years. They were assessed using the Dental Anxiety Scale (DAS) and the Diagnostic Interview Schedule (DIS). The disorders diagnosed by the DIS were major depressive episode, dysthymia, generalized anxiety disorder, panic disorder, agoraphobia, social phobia, simple phobia, obsessive compulsive disorder, conduct disorder, cannabis and alcohol dependence. Results: Overall, 12.5% of study members had DAS scores of 13 or more and were considered to be dentally anxious. Those who were dentally anxious were more likely than the non‐anxious to be diagnosed with one or more psychological disorders (55.0% vs. 42.3%). However, those with DAS scores of 13 or 14 (moderately dentally anxious) were broadly similar to the non‐anxious in terms of their psychological profile. This excess prevalence of psychological disorder was largely accounted for by high rates of disorder among those with DAS scores of 15 or more (highly dentally anxious). The highly anxious were more likely than the non‐anxious to have a diagnosis of conduct disorder, agoraphobia, social phobia, simple phobia or alcohol dependence. Odds ratios ranged from 2.8 to 5.0 after controlling for the effects of gender. The data also suggested that dentally anxious individuals with psychological disorders were more likely to maintain their anxiety over time. Conclusions: In this population of young adults, high rates of psychological disorder were characteristic of those with high levels of dental anxiety. Psychological disorder was related to the maintenance of dental anxiety over time.
Measuring the impact of oral health on life quality in two national surveys – functionalist versus hermeneutic approaches
Authors: McGrath Colman , Bedi Raman
Published: March 2003

Objectives: This study compares a functionalist (quantitative) versus a hermeneutic (qualitative) approach to assessing the impact of oral health on life quality in two United Kingdom national surveys.

Methods: The vehicles for this study were two Office for National Statistics' Omnibus Surveys completed in 1998 and 1999. In both studies a random probability sample of 3000 household addresses was selected from the British Postcode Address File (PAF). The data were collected by face‐to‐face interviews with respondents in their homes about how their oral health status affected their quality of life employing a qualitative, hermeneutic approach (1998) and a functionalist, quantitative approach using a battery of questions (1999).

Results: Irrespective of study design, in both studies it was apparent that the majority of the public perceived their oral health as affecting their life quality (P > 0.05). Likewise, both approaches identified that oral health affected life quality most frequently through physical aspects of oral health rather than social or psychological. However, using the hermeneutic approach, respondents were less likely to cite that their oral health affected specific aspects of their oral health compared to when a battery of questions were used (P < 0.01). Furthermore, socio‐demographic variations in oral health‐related quality of life were more apparent when a battery of questions were employed compared to an open‐ended approach.

Conclusions: Different approaches to assessing oral health‐related quality of life yield similar findings in terms of prevalence of oral health's impact and affected ways (domains). However, the different methods influenced the ability to identify socio‐demographic disparities.
Metals and arsenic in eye shadows
Authors: Sainio Eeva‐Liisa , Jolanki Riitta , Hakala Erkki , Kanerva Lasse
Published: March 2003

The regulations relating to cosmetic products give no limit values for toxic elements such as metals or arsenic occurring as impurities in cosmetic products. The present study of metals (lead, cobalt, nickel, chromium) and arsenic in eye shadows in 88 colors of 25 brands and 49 products provides a basis for assessing the safety of eye shadow. 66 out of 88 (75%) of the colors contained more than 5 ppm of at least one of the elements, and all 49 products contained more than one 1 ppm of at least 1 of the elements. In one color, the amount of all elements was less than 1 ppm. The highest levels of cobalt and nickel were 41 and 49 ppm, respectively. These levels were high enough to cause allergic symptoms in those previously sensitized. Furthermore, long‐term exposure to such levels may probably sensitize. The concentrations of arsenic were extremely low, 2.3 ppm at most. The level of lead was less than 20 ppm in all products. Accordingly, the concentrations of arsenic and lead seemed to be safe. 9 colors had concentrations of water‐soluble chromium exceeding 2 ppm, and a very high level, 318 ppm, was encountered in 1 case. The overall results indicate that eye‐shadows probably have no significant systemic toxicological effects. The groups at greatest risk are those already sensitized to the allergenic elements. Such consumers will have difficulties in choosing suitable products, since these elements in the form of impurities are not declared in the list of ingredients. Manufacturers should demand certification that the raw materials they buy contain no toxic elements. Although some of the products studied were acceptable, many had excessive levels of the elements from the consumer's viewpoint.
Antigen‐presenting cells and keratinocytes express interleukin‐12 in allergic contact dermatitis
Authors: Yawalkar N. , Egli F. , Brand C. U. , Pichler W. J. , Braathen L. R.
Published: March 2003

Interleukin‐12 (IL‐12) has previously been suggested as playing a major rôle in the activation of cytotoxic lymphocytes. Recent reports indicate that cytotoxic CD8+ cells are critically involved in the elicitation phase of contact hypersensitivity reactions. In this study, the in situ expression of IL‐12 was investigated in normal human skin and in allergic contact dermatitis by immunohistochemistry. Skin biopsy specimens were obtained from allergic patch test reactions after 3 days, and from normal skin in 8 subjects. In contrast to normal skin, a strong enhancement of IL‐12 immunoreactivity was observed in the mononuclear cell infiltrate of allergic contact dermatitis. IL‐12 immunoreactivity was mainly located in the cytoplasm of dermal dendritic cells and macrophages as well as of some Langerhans cells. IL‐12‐positive cells were often found in close apposition to lymphocytes. Furthermore, positive immunostaining was also detected in keratinocytes at sites of marked exocytosis and spongiosis in the epidermis. In conclusion, the enhanced in situ expression of IL‐12 may contribute to the activation of cytotoxic lymphocytes and thereby represent an important factor in the pathogenesis of contact hypersensitivity reactions in humans.
Stability of corticosteroid patch test preparations
Authors: Isaksson M. , Gruvberger B. , Persson L. , Bruze M.
Published: March 2003

This study investigated the stability of tixocortol pivalate, budesonide, and hydrocortisone‐17‐butyrate (Hc‐17‐B) when present in a mix with petrolatum and when the corticosteroids were kept separately in petrolatum. The concentrations chosen for the corticosteroids were the same as those used in a study within the European Environmental Contact Dermatitis Research Group (EECDRG), in which 2 corticosteroid mixes (1 with a high concentration and 1 with a low concentration) and the 3 individual constituents, each at 2 concentrations, were patch tested. Ethanolic solutions of each corticosteroid, as well as 2 mixtures of these 3 corticosteroids, were also made up at corresponding concentrations. The preparations were kept at room temperature, refrigerated, and deep frozen, and repeatedly for 1 year, investigations to check stability by high performance liquid chromatography were carried out. A decrease of 20% of the initial value at time 0 was used as the threshold for stability. The petrolatum preparations and the ethanolic solutions of budesonide and tixocortol pivalate were stable for at least the whole investigative period, irrespective of storage conditions, while Hc‐17‐B 1.0% in ethanol kept deep frozen was stable at least during the same period. The latter corticosteroid when kept at room temperature was stable for 3 months only.
Use tests: ROAT (repeated open application test)/PUT (provocative use test): an overview
Authors: Nakada Tokio , Hostynek Jurij J. , Maibach Howard I.
Published: March 2003

As one step in defining the clinical relevance of exposure to an allergen identified with patch testing, use tests (provocative use test (PUT), and repeated open application test (ROAT)) have been used. In 1/2 of the cases of seemingly reliable patch tests, use tests are negative, suggesting that the patient's biologic threshold of response had not been reached with open application dosing. Dramatic differences exist in regional skin reactivity and percutaneous penetration. Negative results of use tests on normal skin may become positive on diseased skin. To refine this assay further, more controlled observations and analysis of reaction differences between normal and damaged skin, and among regional anatomic sites might be performed. In addition, we require a standardized measurement for the results. Use testing has significant potential in refinement of the evidence‐based diagnosis of clinical relevance. However, for general validation, we should fill the deficiencies described above.
The use of protective gloves and the prevalence of hand eczema, skin complaints and allergy to natural rubber latex among dental personnel in the county of Uppsala, Sweden
Authors: Lindberg Magnus , Silverdahl Margareta
Published: March 2003

During the past decade, there has been an increasing problem with acrylate allergy and natural rubber latex (NRL) allergy among dental personnel. The aim of the present study was to evaluate the prevalence of these problems among dentists, dental nurses and dental hygienists in Uppsala county, Sweden. The study was based on a self‐administered questionnaire sent to 690 persons with 527 responders (76%). The most common skin problem was dry skin, fissures and/or itching on the hands. Of the 72 persons (13.6%) reporting to have suffered from hand eczema during the past 12 months, 41 were patch tested with the TRUE Test standard series and the Swedish dental screening series. In the patch tested group, 9.8% reacted to 1 or more of the acrylates. In addition, 389 persons were tested for NRL allergy with the Pharmacia Upjohn CAP‐RAST test, and of these, we found 7.2% to be positive. The prevalence of self‐reported hand eczema and the number of positive CAP‐RAST tests differed between the 3 occupations, with higher figures for the dentists. There was also a correlation between atopic eczema and hand eczema. Of those reporting skin symptoms, 67.7% connected them to the place of work and 28.8% related them to the use of gloves.
Topical application of docosanol‐ or stearic acid‐containing creams reduces severity of phenol burn wounds in mice
Authors: Khalil M. H. , Marcelletti John F. , Katz Lee R. , Katz David H. , Pope Laura E.
Published: March 2003

Because of their reported antiviral and anti‐inflammatory activities, cream formulations containing n‐docosanol (docosanol) or stearic acid were tested for effects on chemically‐induced burns in mice. In this model, injury was induced by painting the abdomens of mice with a chloroform solution of phenol. This was followed by the topical application of test substances 0.5, 3, and 6 h later. Progression of the wounds was assessed by a single evaluator after 8 h, using a numerical score of gross morphology. Docosanol‐ and stearic acid‐containing creams substantially and reproducibly lessened the severity and progression of skin lesions compared to untreated sites with a 76% and 57% reduction in mean lesion scores, respectively. Untreated wounds appeared red and ulcerated; docosanol cream‐treated wounds showed only slight erythema.
Positive nickel patch tests do not intensify positive reactions to adjacent patch tests with dichromate
Authors: Brasch Jochen , Kreilgård Bo , Henseler Tilo , Aberer Werner , Fuchs Thomas , Pflüger Rafael , Hoeck Ulla , Gefeller Olaf
Published: March 2003

The possible interference of neighbouring allergic patch‐test reactions is still an open question. In this study, we investigated whether there is a distance‐related mutual modification of neighbouring allergic patch‐test reactions to nickel sulfate and potassium dichromate. We used a double‐blind multicentre study design with randomized attachment of special TRUE Tests with 1, 3 and 7 cm distance between nickel sulfate and potassium dichromate patches. 589 patients with a history of nickel allergy (523 female, 66 male) were tested, with a mean age of 35 years. A log‐linear modelling approach was used for statistical assessment of the relation between the distance separating neighbouring patch tests with nickel and dichromate and the reactions to the allergens. Non‐reproducibility coefficients were compared by the generalized version of Fisher's exact test for arbitrary 2‐dimensional contingency tables. For the left side of the back, virtually no differences (p=0.70) were found in the reaction patterns obtained for the 3 distances separating nickel and dichromate patch tests. On the right side of the back, the number of reactions to dichromate patches with only 1 cm distance from moderate/strong nickel reactions was lower than the number of positive dichromate tests at larger distances from nickel tests (on the border of statistical significance: p=0.05). Corresponding side‐related results were obtained for subgroups of patients with and without a history of atopic dermatitis. The non‐reproducibility of reactions to dichromate was not significantly related to the distance between neighbouring tests. Our data argue against a “spillover“ effect of strong/moderate nickel reactions, but indicate that such reactions may, under certain conditions, attenuate adjacent reactions to an unrelated allergen. In the case of future verification, this will have implications for the interpretation of patch tests.
Contact dermatitis in Korean dental technicians
Authors: Lee Jun Young , Yoo Jeong Min , Cho Baik Kee , Kim Hyung Ok
Published: March 2003

The high risk of occupational contact dermatitis in dental personnel are well accepted throughout the world. There are few reports concerning occupational skin disease in dental personnel in Korea. The purposes of this study were to investigate the frequency, characteristics and causative factors of contact dermatitis in Korean dental technicians. Recording of personal history, physical examination and patch tests with the Korean standard series and dental screening series were performed in 49 dental technicians. Most of the subjects were exposed to a variety of compounds, including acrylics, metals, plaster, alginate, etc. 22 (44.9%) subjects had contact dermatitis, present or past, and the site involved was the hand in all 22. The most common clinical feature of hand dermatitis was itching (77.3%); scaling, fissuring and erythema were other common clinical features. Metals, including potassium dichromate (24.5%), nickel sulfate (18.4%), mercury ammonium chloride (16.3%), cobalt chloride (12.2%) and palladium chloride (10.2%), showed high positive rates in patch test results of 49 dental technicians. 7 positive reactions to the various acrylics were found in 3 subjects. In our study, the frequency and clinical features of the contact dermatitis showed a similarity to other reports, though the patch test results were somewhat different; a higher patch‐positive reaction to metals and a relatively lower patch‐positive reaction to acrylics than the patch test results reported in Europe.
Effect of a lipid‐rich emollient containing ceramide 3 in experimentally induced skin barrier dysfunction
Authors: Kucharekova M. , Schalkwijk J. , Van De Kerkhof P. C. M. , Van De Valk P. G. M.
Published: March 2003

In the present study we compared the effect of a ceramide 3‐containing emollient (Locobase® Repair) with a control emollient (vaselinum album/cremor lanette ana) and untreated damaged skin using clinical, bioengineering and immunohistochemical methods in two different models of experimentally induced skin barrier dysfunction. In model A (n = 13) skin barrier dysfunction was inflicted at three investigation sites by tape stripping. In model B (n = 13) the volunteers were patch tested at three investigation sites with sodium dodecyl sulphate (0.2%) for 4 h a day for 4 consecutive days. The investigation sites were treated once a day with the above‐mentioned agents. Irritant reaction was assessed daily by erythema scoring and measurements of transepidermal water loss (TEWL). After 5D, punch biopsies were taken from all sites. Immunohistochemical assessment was carried out with respect to epidermal proliferation, epidermal differentiation and Langerhans cells. Tape stripping resulted in an erythematous reaction and an increase of TEWL associated with up‐regulation of cycling cells, involucrin and expression of cytokeratin 16. At day 4, ceramide 3‐containing emollient significantly decreased (p < 0.03) the erythema score, TEWL and cycling cells in comparison with the untreated site. Repetitive exposure to SDS induced a variable degree of erythema, gradual increase of TEWL, an increase of cycling cells, and up‐regulation of involucrin, E‐FABP and SKALP. The treatment with the control emollient significantly prevented erythema, increase of TEWL and cycling cells at day 4 compared to the untreated site. In summary, the present study demonstrated that both tested emollients improve skin barrier in different conditions compared to the untreated skin. There is some indication that formulations containing skin‐related lipids might be of benefit in barrier disruption following tape stripping. Different models and clinical trials are needed to establish the usefulness in specific conditions of emollients containing skin‐related lipids.
The effects of low level laser irradiation on osteoblastic cells
Authors: Coombe A. R. , Ho C‐T. G. , Darendeliler M. A. , Hunter N. , Philips J. R. , Chapple C. C. , Yum L. W. P.
Published: March 2003

Low level laser therapy has been used in treating many conditions with reports of multiple clinical effects including promotion of healing of both hard and soft tissue lesions. Low level laser therapy as a treatment modality remains controversial, however. The effects of wavelength, beam type, energy output, energy level, energy intensity, and exposure regime of low level laser therapy remain unexplained. Moreover, no specific therapeutic window for dosimetry and mechanism of action has been determined at the level of individual cell types. The aim of this study was to investigate the effects of low level laser irradiation on the human osteosarcoma cell line, SAOS‐2. The cells were irradiated as a single or daily dose for up to 10 days with a GaAlAs continuous wave diode laser (830 nm, net output of 90 mW, energy levels of 0.3, 0.5, 1, 2, and 4 Joules). Cell viability was not affected by laser irradiation, with the viability being greater than 90% for all experimental groups. Cellular proliferation or activation was not found to be significantly affected by any of the energy levels and varying exposure regimes investigated. Low level laser irradiation did result in a heat shock response at an energy level of 2 J. No significant early or late effects of laser irradiation on protein expression and alkaline phosphatase activity were found. Investigation of intracellular calcium concentration revealed a tendency of a transient positive change after irradiation. Low level laser irradiation was unable to stimulate the osteosarcoma cells utilised for this research at a gross cell population level. The heat shock response and increased intracellular calcium indicate that the cells do respond to low level laser irradiation. Further research is required, utilising different cell and animal models, to more specifically determine the effects of low level laser irradiation at a cellular level. These effects should be more thoroughly investigated before low level laser therapy can be considered as a potential accelerator stimulus for orthodontic tooth movement.
Genetic changes in sweat gland carcinomas
Authors: Takata Minoru , Hashimoto Ken , Mehregan Parius , Lee Min W. , Yamamoto Akifumi , Mohri Shinobu , Ohara Kuniaki , Takehara Kazuhiko
Published: March 2003

The molecular pathogenesis of malignant appendageal tumors is poorly understood. Immunohistochemical staining, polymerase chain reaction (PCR)‐based loss of heterozygosity (LOH) and sequencing analyses were performed in a mixed group of 21 sweat gland carcinomas. LOH was mostly confined to the chromosome arm 17p. None of the remaining 17 tumors showed LOH at any loci. Nuclear accumulation of p53 protein was observed in 3 tumors, all of which also showed LOH of 17p. One eccrine gland adenocarcinoma showed allelic loss of 17p and a Cys 176 Arg mutation in the p53 gene. The other three tumors that showed LOH of 17p, however, had wild‐type p53 genes. A clear transition from benign eccrine poroma to porocarcinoma that was associated with p53 protein stabilization and allelic loss was observed in one tumor. One eccrine porocarcinoma/undifferentiated adnexal carcinoma showed prominent microsatellite instability, probably reflecting an underlying defect in DNA mismatch repair. Overexpression of erbB‐2 was observed in three tumors. The low frequencies of LOH and p53 alterations in sweat gland carcinomas contrasted with the multiple genetic defects normally observed in cutaneous squamous cell carcinomas, and may be partly explained by the relative protection of cutaneous appendages from ultraviolet light and other environmental mutagens.
CD34‐positive cellular blue neviNote
Authors: Smith Kathleen J. , Germain Marguerite , Williams John , Skelton Henry G.
Published: March 2003

Background: Although cellular blue nevi (CBN) are well known and characterized, the histopathologic and clinical spectrum of these tumors continues to evolve. We report four CBN with a distinctive histologic and immunohistochemical pattern.

Methods: The histologic features and immunohistochemical staining for S‐100 protein, HMB‐45, Bcl‐2 and CD34 of four CBN with distinctive features were evaluated using routine methods and compared to common CBN.

Results: All four of these distinctive CBN where known to be congenital, and all showed aggregates of plump spindled cells with round to oval nuclei in aggregates and more slender spindled cells with thin wavy nuclei. The slender, spindled cells showed an infiltrative pattern laterally into the dermis and deep into the subcutaneous fat. All four tumors showed diffuse expression of an immunohistochemical stain for CD34, as well as for S‐100 protein, Bcl‐2, and HMB‐45.

Conclusion: Positive immunohistochemical staining with the progenitor marker CD34 defines a subset of CBN. These tumors appear to fit within the spectrum of neurocristic cutaneous hamartomas and may arise from more primitive neurocristically derived cells. Further follow‐up of these tumors will be necessary to determine whether this subset of CBN defines a subset with a characteristic biologic behavior.
A case of Sweet's syndrome developed after the treatment of herpes simplex infection in a metastatic breast cancer patient
Authors: Coskun Ugur , Gunel Nazan , Senol Esin , Ilter Nilsel , Dursun Ayse , Tuzun Dilek
Published: March 2003

Background:Sweet's syndrome or acute febrile neutrophilic dermatosis is associated with several systemic diseases such as malignancies and infectious diseases.

Methods:We present a 34‐year‐old woman with Sweet's syndrome associated with both herpes infection and metastatic disease.

Results:Skin biopsy showed neutrophilic infiltrates in the dermis confirming the diagnosis of Sweet's syndrome.

Conclusions:To our knowledge, this is the second case of Sweet's syndrome associated with herpes simplex infection in the literature. Further observations are required to determine the relationship between Sweet's syndrome and herpetic infection.
Expression of vascular endothelial growth factor in basal cell carcinoma and cutaneous squamous cell carcinoma of the head and neck
Authors: Bowden John , Brennan Peter A. , Umar Tijjani , Cronin Andrew
Published: March 2003

Background:  Basal cell carcinomas (BCC) and squamous cell carcinomas (SCC) can both arise from any cutaneous epithelial surface. BCC are slow growing and rarely metastasise, whereas SCC are usually more aggressive. It is likely that the angiogenic process plays a key role in determining rate of growth and propensity for dissemination. Angiogenesis is a complex process requiring many factors and a pivotal group of proteins involved in this process is vascular endothelial growth factor (VEGF).

Methods:  Immunohistochemical expression of VEGF was assessed in 44 cases of BCC and 41 cases of cutaneous SCC from the head and neck region.

Results:  VEGF was expressed by blood vessel endothelial cells in both adjacent skin and tumour, and in the basal keratinocyte layer of epidermis. In BCC, VEGF was expressed by tumour epithelial cells, predominantly at the invasive tumour front, in 24/44 cases and its expression was significantly greater than in adjacent skin (p = 0.038). More widespread VEGF expression was found in 32/41 cases of SCC, and it was significantly associated with the degree of tumour differentiation (p < 0.001).

Conclusions:  The patterns of VEGF expression in BCC and SCC may help to explain the different behaviour that is usually seen with these tumours.
The Impact of Financial Incentives on Physician Productivity in Medical Groups
Authors: Conrad Douglas A. , Sales Anne , Liang Su‐Ying , Chaudhuri Anoshua , Maynard Charles , Pieper Lisa , Weinstein Laurel , Gans David , Piland Neill
Published: March 2003

Objective. To estimate the effect of financial incentives in medical groups—both at the level of individual physician and collectively—on individual physician productivity.

Data Sources/Study Setting. Secondary data from 1997 on individual physician and group characteristics from two surveys: Medical Group Management Association (MGMA) Physician Compensation and Production Survey and the Cost Survey; Area Resource File data on market characteristics, and various sources of state regulatory data.

Study Design. Cross‐sectional estimation of individual physician production function models, using ordinary least squares and two‐stage least squares regression.

Data Collection. Data from respondents completing all items required for the two stages of production function estimation on both MGMA surveys (with RBRVS units as production measure: 102 groups, 2,237 physicians; and with charges as the production measure: 383 groups, 6,129 physicians). The 102 groups with complete data represent 1.8 percent of the 5,725 MGMA member groups.

Principal Findings. Individual production‐based physician compensation leads to increased productivity, as expected (elasticity=.07, p<.05). The productivity effects of compensation methods based on equal shares of group net income and incentive bonuses are significantly positive (p<.05) and smaller in magnitude. The group‐levelfinancial incentive does not appear to be significantly related to physician productivity.

Conclusions. Individual physician incentives based on own production do increase physician productivity.
Reasons for choosing dentistry as a career – a survey of dental students attending a dental school in Ireland during 1998–99
Authors: Hallissey Joseph , Hannigan Ailish , Ray Noel
Published: March 2003

The motivations for choosing dentistry as a career in the Republic of Ireland are not clearly defined. To better understand why students choose this occupation, 150 undergraduate dental students of all grades at a University Dental School were surveyed during the academic year 1998–99. Candidates were asked to score the influence of certain factors on their decision to choose dentistry as a career, and were given the opportunity to add commentary. The overall response rate was 80.6%. About 2/3 indicated dentistry was their 1st career choice, with medicine being the primary alternative. Reasons for choosing dentistry included perceived ease of employment, being self‐employed, working regular hours, followed by an opportunity of good income, and the opportunity to help people. Having relatives or friends in the profession and lifelong ambition were the least important factors for this sample. Extrinsic factors relating to employment conditions had a strong positive correlation (p<0.0001) with each other, while lifelong ambition had a strong negative correlation (p=0.004) with significant financial reward. No significant differences were found in most responses when analysed by gender or year in school. It is concluded that this sample of students is attracted to dentistry primarily due to a positive perception of working conditions, followed by the altruistic motivations of helping people and improving their appearance.
Computer assisted learning. A Review
Authors: Schittek Martin , Mattheos Nikos , Lyon H. C. , Attström Rolf
Published: March 2003

Since 1980 the amount of medical information has doubled approximately every second year. This implies that oral health students as well as professionals need to manage the flow of information rationally, in order to learn how to undertake evidence‐based decision‐making for diagnosis and treatment in a given patient situation. Current research indicates that computer connected databases and computer assisted learning (CAL) may enhance learning and provide the clinician with information for decision‐making when treating patients. Multimedia for CAL, which combines audio and visual data in an interactive form, has proved to be an effective tool in education. CAL may supplement and reinforce more traditional learning and create opportunities to illustrate clinical situations in an interactive way. CAL has the potential to help students develop skills and knowledge. Students, staff and professionals consider CAL stimulating and motivating. Students easily adapt to CAL although their current computer literacy is still low. New authoring tools make it easier for faculties to develop their own CAL software. In the future we will see more sophisticated software with virtual patients who can communicate and interact with the student in a very realistic way. The software will even “step out” from the screen and help the student with clinical procedures. However, at present CAL should not replace traditional education, but rather be used more as a supplement and for self‐directed studies.
A pilot study comparing the effectiveness of conventional training and virtual reality simulation in the skills acquisition of junior dental students
Authors: Quinn Frank , Keogh Paul , McDonald Ailbhe , Hussey David
Published: March 2003

The use of virtual reality (VR) in the training of operative dentistry is a recent innovation and little research has been published on its efficacy compared to conventional training methods. To evaluate possible benefits, junior undergraduate dental students were randomly assigned to one of three groups: group 1 as taught by conventional means only; group 2 as trained by conventional means combined with VR repetition and reinforcement (with access to a human instructor for operative advice); and group 3 as trained by conventional means combined with VR repetition and reinforcement, but without instructor evaluation/advice, which was only supplied via the VR‐associated software. At the end of the research period, all groups executed two class 1 preparations that were evaluated blindly by ‘expert’ trainers, under traditional criteria (outline, retention, smoothness, depth, wall angulation and cavity margin index). Analyses of resulting scores indicated a lack of significant differences between the three groups except for scores for the category of ‘outline form’, for group 2, which produced significantly lower (i.e. better) scores than the conventionally trained group. A statistical comparison between scores from two ‘expert’ examiners indicated lack of agreement, despite identical written and visual criteria being used for evaluation by both. Both examiners, however, generally showed similar trends in evaluation. An anonymous questionnaire suggested that students recognized the benefits of VR training (e.g. ready access to assessment, error identification and how they can be corrected), but the majority felt that it would not replace conventional training methods (95%), although participants recognized the potential for development of VR systems in dentistry. The most common reasons cited for the preference of conventional training were excessive critical feedback (55%), lack of personal contact (50%) and technical hardware difficulties (20%) associated with VR‐based training.
Population dynamics in a Danish metapopulation of spadefoot toads Pelobates fuscus
Authors: Hels Tove
Published: March 2003

If an amphibian species has a high degree of site fidelity to its natal pond, subpopulations do not mix, and this may have implications: the subpopulations may get different because of genetic drift, and their status may be affected due to stochastic events. During a four‐year period (1994–1997), demographic parameters of a Danish metapopulation consisting of ca 1000 adult Pelobates fuscus in five subpopulations were investigated with the aim of quantifying exchange of individuals in subpopulations and potential differences in demographic parameters, and to clarify population regulating mechanisms. This was done through the use of drift fences surrounding the five breeding ponds, individual marking (PIT‐tagging) and weight recordings of the adult females. Metamorphs were recorded when leaving the pond. There was no significant differences between ponds in sex ratio, eggs laid per female, fraction of females breeding and survival of eggs to froglets and of adults. However, there was a significant difference in juvenile survival (52% in one pond and 31% in the others). Sex ratio was 1.70 males:1 female. Mean number of eggs laid per female in the pond was 1762. The number of eggs laid was age‐specific, fecundity peaking at age five. Larval survival rate was density dependent: decreasing in an overcompensating fashion at high densities. Exchange rate between ponds was low; 1.09% of the marked and recaptured adult population was found to change pond during the study period. The low exchange rate was confirmed in a simple translocation experiment. This population shows features of a source‐sink metapopulation where the identity of the source pond changes due to succession. It is presumably regulated either in the larval stage by density dependent mechanisms (in the subpopulations with many adults) or in the adult stage by density independent mechanisms (in the subpopulations with few adults).
Sex‐ and age‐dependent effects of population density on life history traits of red deer Cervus elaphus in a temperate forest
Authors: Bonenfant Christophe , Gaillard Jean‐Michel , Klein François , Loison Anne
Published: March 2003

We studied both the short‐ and long‐term effects of density on three life history traits of a red deer population inhabiting a temperate forest. Both male and female body mass increased when population density decreased, but male mass changed to a greater extent than female mass. Density did not influence female survival irrespective of age, however, survival of males was lower at high density for all age classes except the prime‐age class. Pregnancy rates of primiparous females increased markedly with decreasing density, whereas those of adult hinds were fairly constant and unrelated to density. For both sexes, of the studied life history traits we detected a long‐term effect of density at birth (cohort effect) only on body mass. These results suggest that density influences life history traits in the same way as factors of environmental variation such as climate. In this population we did not find any evidence for an influence of climatic conditions on life history traits of red deer. Both mild winters and the absence of summer droughts during the study period could account for such an absence of climatic effects. We interpreted our results to show that 1) as expected for a highly dimorphic and polygynous species such as red deer, male traits showed consistently higher sensitivity to variation in density than female traits, illustrating possible costs caused by sexual selection in males, 2) the female‐based Eberhardt's model according to which increasing density should sequentially affect juvenile survival, reproductive rates of primiparous females, reproductive rates of adults and lastly adult survival was only partly supported because we found that pregnancy rate of primiparous females rather than juvenile survival was the most sensitive trait to variation in density. We propose that including variation in male traits would improve the accuracy of models of population dynamics of large mammals, at least for highly dimorphic species. Because the population we studied was not fenced, we only measured apparent survival. We discuss how dispersal, in relation to the phenotypic quality of young deer, might be a potential regulating factor under such conditions.
Conceptual and mathematical relationships among methods for spatial analysis
Authors: Dale Mark R. T. , Dixon Philip , Fortin Marie‐Josée , Legendre Pierre , Myers Donald E. , Rosenberg Michael S.
Published: March 2003

A large number of methods for the analysis of the spatial structure of natural phenomena (for example, the clumping or overdispersion of tree stems, the positions of veins of ore in a rock formation, the arrangement of habitat patches in a landscape, and so on) have been developed in a wide range of scientific fields. This paper reviews many of the methods and describes the relationships among them, both mathematically, using the cross‐product as a unifying principle, and conceptually, based on the form of a moving window or template used in calculation. The relationships among these methods suggest that while no single method can reveal all the important characteristics of spatial data, the results of different analyses are not expected to be completely independent of each other.
Granulocytopoiesis versus cytokine activities in peritoneal diffusion chamber cultures in the mouse
Authors: Wang Xiuli , Brekken Kristin B. , Siebke Else‐Marie , Stokke Gro , Sørlid Hanne K. , Benestad Haakon B.
Published: March 2003

Abstract: Regulation of granulocyte formation was studied by correlating granulocytopoiesis in diffusion chambers with activities of putative regulatory cytokines in such chambers. The implantation procedure increased the levels in 1‐ and 2‐d chambers of interleukin 6 (IL‐6), G‐CSF, TNF‐α, and non‐specific granulocyte/macrophage (G/M) colony‐stimulating activities (CSA), assessed with bioassays and immunoassays. The activities subsided rapidly thereafter. They could be increased by vinblastine, cyclophosphamide, and a sterile inflammatory reaction (s.c. implanted copper rods; Cu‐r). Anti‐inflammatory indomethacin curtailed the IL‐6, but raised the TNF‐α, G‐CSF, and CSA levels in Cu‐r mice. Interferon inducer poly‐I:C augmented G‐CSF, but decreased TNF‐α levels. Mouse blood cells cultured in chambers expanded their granulocyte/macrophage progenitor population rapidly during the first week of culture; this population being significantly larger on day 3 in perturbed than in unperturbed mice. A marked decline followed in the second week, significantly larger in mice given cytotoxic treatment than in controls. Peritoneal G‐CSF and TNF‐α may explain progenitor and granulocyte growth and development in diffusion chambers during the first week of culture. GM‐CSF and IL‐3 were apparently without any influence. None of the peritoneal cytokines assayed could explain the population decline during the second week, which was possibly caused by exhaustion of earlier progenitor cells, rather than by intra‐chamber feedback mechanisms.
Filtered platelet concentrates from pooled buffy coats show comparable storagelesions when stored for 9 d at 20–24°C or when supplemented with ThromboSol™at 2–6°C
Authors: Schaller M. , Hofmann A. , Connor J. , Nydegger U. E.
Published: March 2003

Abstract: The present study investigated the quality of platelet concentrates from pooled buffy coat (PCBC) along different production steps and during storage to characterize storage lesions reflected by platelet activation, changing metabolic and cell turnover status (pH, LDH activity). These criteria were compared in conventionally stored PCBCs (20–24°C, n=8, Group I) to cold stored PCBCs (2–6°C, n=8, Group II) when supplemented with ThromboSol™. Platelet activation was measured on days 1, 3, 7 and 9 by flow cytometry using fluorescein–isothiocyanate‐labeled monoclonal antibodies (mAbs) against glycoprotein IIb/IIIa (CD41a, PAC‐1 and LIBS‐1), P‐selectin (CD62P) or CD40 ligand receptor (CD40L) in combination with a phycoerythrin‐labeled panspecific platelet marker against GPIb (CD42b). The platelet activation assessed with mAbs PAC‐1, CD41a, LIBS‐1 and CD40L showed an overall activation of 98±4% (mean value ±1 SD) at day 7 in both groups, except for CD62P, which was significantly lower in Group II. A storage‐dependent greater platelet loss occurred in Group II compared to Group I, 42% vs. 19% (p<0.05 on day 9). We could demonstrate that platelets stored in ThromboSol™ show about the same in‐vitro activation as conventionally stored PCBCs, but their clinical usefulness needs to be investigated.
Not the presence but the amount of clonal DNA detectable in remission of acute myeloid leukemia is predictive for relapse
Authors: Reif Susanne W , Wiesner Dagmar , Duell Thomas , Mittermueller Johann , Schmetzer Helga M
Published: March 2003

Abstract: Objectives: The persistence of clonal cells after chemotherapy, or a re‐emerging of clonal cells in remission (CR) or at relapse in patients with acute myeloid leukemia (AML) was studied to assess the prognostic significance of the amount of clonal DNA in predicting the clinical outcome. Methods: Clonal rearrangements in the gene sequences of retinoic acid receptor (RAR) α, major breakpoint cluster region (M‐bcr), immunoglobulin (Ig)‐JH, T‐cell receptor (TcR) β, myeloid lymphoid leukemia or cytokines (GM‐CSF, G‐CSF, IL‐3) detected in bone marrow samples from 37 patients with primary AML (pAML) or secondary AML (sAML) were investigated. A relative increase or decrease of clonal DNA in the course of AML was evaluated by comparing the optical densities of DNA bands of the rearranged genes and the total amount of DNA. Results: High amounts of clonal DNA were detectable at diagnosis, during persisting disease and at relapse (Ø 39%, 35%, or 38% of total DNA, respectively), compared to 20% in complete remission (CR). Amounts of clonal DNA (except for Ig‐JH gene rearrangements) were of prognostic significance at diagnosis, patients with less than 33% clonal DNA were characterized by significantly longer relapse‐free survival times (all cases: p = 0.01; pAML: p = 0.002). Patients in CR exhibiting less than 5% (all cases) or 15% (pAML) clonal DNA showed longer relapse‐free survival times (p = 0.08 or p = 0.03, respectively). Vice versa, significantly higher amounts of clonal DNA (all cases 51% vs. pAML 54%) could be detected in cases studied at diagnosis who relapsed in the following 5 months (all cases p = 0.01) or 14 months (pAML p = 0.007). Significantly higher amounts of clonal DNA (33%) could be detected in cases studied in CR who relapsed in the following 4 months (all cases p = 0.002 or pAML p = 0.006, respectively). Moreover, we could prove disease progression on a cellular level months before the clinical onset of sAML after a period of MDS. Conclusions: Clonal, gene‐rearranged DNA is regularly detectable at diagnosis and during persisting AML, in CR and at relapse. However, the presence, rather than the amount of clonal DNA detectable in CR is predictive for relapse. These data might indicate the significance of gene rearrangement analyses in the course of AML to identify cases with a high risk of relapse, independently from the karyotype.
Bronchiolitis obliterans organizing pneumonia in a patient with chronic myelogenous leukemia developing after initiation of interferon and cytosine arabinoside
Authors: Patel Meera , Ezzat Wendelin , Pauw Kathy L. , Lowsky Robert
Published: March 2003

Abstract: A 59‐yr‐old man developed fevers, shortness of breath, persistent cough and weight loss, shortly after initiation of therapy with interferon‐alpha 2a and cytosine arabinoside for treatment of chronic myelogenous leukemia. Radiologic pulmonary infiltrates and lung tissue biopsy were consistent with bronchiolitis obliterans organizing pneumonia (BOOP). After discontinuation of the chemotherapeutic drugs, the pneumonic symptoms and chest roentgenogram infiltrates resolved. This report suggests that treatment with interferon‐alpha, in combination with cytosine arabinoside, may produce the rare complication of BOOP.