Facilitators and barriers to online group work in higher education within health sciences - a scoping review

INTRODUCTION

In health education, group work is essential to prepare students for working in health care and medical teams. Following the widespread adoption of online teaching, group work increasingly takes place in online environments. Although successful group work can provide good learning outcomes, it is unclear what facilitates or hinders online group work in health science education, and to what extent this topic has been addressed. Thus, this scoping review aimed to identify the facilitators and barriers to online group work in higher health education, provide an overview of the scientific literature related to the topic, and identify knowledge gaps in the research.

METHODS

This scoping review was guided by the methodological framework described by Arksey and O'Malley, and reporting is in accordance with Preferred Reporting Items for Systematic Reviews and Meta-Analysis Extension for Scoping Review (PRISMA-ScR). Eight online databases were searched for scientific articles published between 2012 and 2022. At least two researchers independently screened records and full-text articles and charted data including article characteristics and key information related to the research question. Findings were categorized and summarized based on the Community of Inquiry Framework.

RESULTS

After screening 3671 records and 466 full-text articles, 39 articles met the inclusion criteria. The review revealed smaller group size, consistency in group composition and joint responsibility to be facilitators. Challenges with group communication, scheduling synchronous meetings and technical issues were identified as barriers. Our findings supported the importance of all three elements of the Community of Inquiry Framework: social, cognitive, and teaching presence.

CONCLUSION

This review provides an overview of facilitators and barriers to online group work in health science education. However, there is a need for further investigation of these factors and studies addressing this topic from the teachers' perspective.

Experiences of social support by participants with morbid obesity who participate in a rehabilitation program for health-behavior change: a qualitative study

BACKGROUND

Obesity is a global public health concern with significant implications for individuals' physical health and overall well-being. Health-behavior change programs are crucial for addressing obesity and its associated health risks. Social support plays a central role in facilitating successful outcomes in these programs, yet limited qualitative research exists on the experiences of individuals with morbid obesity participating in such interventions. Thus, this study explores how participants with morbid obesity experienced social support in a group-based rehabilitation program for health-behavior change.

METHODS

Fourteen participants in a group-based rehabilitation health-behavior change program in Norway were interviewed using semi-structured interviews. Data were analyzed with thematic analysis.

RESULTS

The thematic analysis revealed three primary sources of social support: support from other participants in the group, social support from family and friends, and support from the interdisciplinary team. The participants emphasized the significance of ongoing social support throughout their health-behavior change program. Participants appreciated fostering a sense of community and regular interaction with other members of the program to ensure ongoing social support.

CONCLUSIONS

Participants outlined the importance of maintaining a sense of community in the group and appreciated platforms for facilitating ongoing interactions and support among group participants. Future studies should focus on long-term interventions, tailored approaches for individuals with diverse needs involving family and friends, and the impact of enhanced peer support. By understanding the role of social support in health-behavior change programs, interventions can be optimized to better support individuals with morbid obesity.

Experiences of living with binge eating disorder and facilitators of recovery processes: a qualitative study

BACKGROUND

Binge eating disorder (BED) is the most prevalent eating disorder worldwide. BED is often associated with low quality of life and mental health problems. Given the complexity of the disorder, recovery may be challenging. Since BED was only recently specified as a diagnostic category by the World Health Organization (2021), little is known about how patients experience living with BED in everyday life. This study aimed to explore how patients experience living with BED and to investigate factors perceived as facilitating recovery.

METHOD

Individual interviews were conducted with six patients in a rehabilitation programme for recovery from BED. Interviews were conducted digitally and verbally transcribed between December 2020 and January 2021. The analysis was based on Malterud's systematic text condensation.

RESULTS

Being diagnosed with BED could be experienced as a relief. The participants perceived living with BED as a challenging addiction. They struggled with a low self-image and experienced a lack of understanding from others, resulting in shame. Self-compassion and social support from friends and family and through participation in a rehabilitation programme were important facilitators of recovery.

CONCLUSION

Participants perceived living with BED as a challenging addiction. They struggled with low self-esteem and experienced a lack of understanding from others, resulting in shame. Being diagnosed with BED was perceived as a relief. They appreciated that issues related to mental health were addressed during rehabilitation to better understand the complexity of BED. Knowledge about BED, as well as the difficulties of living with BED among family members and friends might help patients with BED feel less ashamed of their disorder and could thus contribute to increased self-compassion.

Purchase of ultra-processed foods in Norway: a repeated cross-sectional analysis of food sales in 2013 and 2019

OBJECTIVE

A dietary pattern dominated by ultra-processed foods has been associated with non-communicable diseases in several studies. A previous study from 2013 found a high share of ultra-processed foods in Norwegian food sales. This study aimed to investigate the current share of ultra-processed foods in Norway and the development in expenditure on ultra-processed foods from 2013.

DESIGN

A repeated cross-sectional analysis of scanner data from the Consumer Price Index from September 2013 and 2019 and an investigation of the processing degree according to the NOVA classification system.

SETTING

Food sales in Norway.

PARTICIPANTS

Norwegian grocery stores (n 180, for both time periods).

RESULTS

The share of expenditure in 2019 was highest for ultra-processed foods (46·5 %) and minimally or unprocessed foods (36·3 %), followed by processed foods (8·5 %) and processed culinary ingredients (1·3 %). An increasing degree of processing was found for several of the food groups between 2013 and 2019; however, most effect sizes were weak. In 2019, soft drinks became the most frequently purchased food item, surpassing milk and cheese, with the highest expenditure in Norwegian grocery stores. Increases in expenditure on ultra-processed foods were mainly due to increased expenditures on soft drinks, sweets and potato products.

CONCLUSIONS

A high share of expenditure on ultra-processed food was found in Norway, which may imply a high consumption of these foods. The change in expenditure of NOVA groups between 2013 and 2019 was small. Carbonated and non-carbonated soft drinks were the most frequently purchased products in Norwegian grocery stores and contributed to most of the expenditures.

Development and Evaluation of a Serious Game Application to Engage University Students in Critical Thinking About Health Claims: Mixed Methods Study

BACKGROUND

Misleading health claims are widespread in the media, and making choices based on such claims can negatively affect health. Thus, developing effective learning resources to enable people to think critically about health claims is of great value. Serious games can become an effective learning resource in this respect, as they can affect motivation and learning.

OBJECTIVE

This study aims to document how user insights and input can inform the concept and development of a serious game application in critical thinking about health claims in addition to gathering user experiences with the game application.

METHODS

This was a mixed methods study in 4 successive phases with both qualitative and quantitative data collected in the period from 2020-2022. Qualitative data on design and development were obtained from 4 unrecorded discussions, and qualitative evaluation data were obtained from 1 recorded focus group interview and 3 open-ended questions in the game application. The quantitative data originate from user statistics. The qualitative data were analyzed thematically, and user data were analyzed using nonparametric tests.

RESULTS

The first unrecorded discussion revealed that the students' (3 participants') assessment of whether a claim was reliable or not was limited to performing Google searches when faced with an ad for a health intervention. On the basis of the acquired knowledge of the target group, the game's prerequisites, and the technical possibilities, a pilot of the game was created and reviewed question by question in 3 unrecorded discussions (6 participants). After adjustments, the game was advertised at the Oslo Metropolitan University, and 193 students tested the game. A correlation (r=0.77; P<.001) was found between the number of replays and total points achieved in the game. There was no demonstrable difference (P=.07) between the total scores of students from different faculties. Overall, 36.3% (70/193) of the students answered the evaluation questions in the game. They used words such as "fun" and "educational" about the experiences with the game, and words such as "motivating" and "engaging" related to the learning experience. The design was described as "varied" and "user-friendly." Suggested improvements include adding references, more games and modules, more difficult questions, and an introductory text explaining the game. The results from the focus group interview (4 participants) corresponded to a large extent with the results of the open-ended questions in the game.

CONCLUSIONS

We found that user insights and inputs can be successfully used in the concept and development of a serious game that aims to engage students to think critically about health claims. The mixed methods evaluation revealed that the users experienced the game as educational and fun. Future research may focus on assessing the effect of the serious game on learning outcomes and health choices in randomized trials.

Food Habits and Forms of Food Insecurity among International University Students in Oslo: A Qualitative Study

A growing number of studies indicate that university students and especially international students are prone to experiencing food insecurity (FI). Still, few studies have investigated forms of FI among international students in Europe. Thus, this qualitative study aims to explore experiences regarding FI among international university students in Oslo. Sixteen semi-structured interviews were conducted between May and June 2022 and analyzed using a thematic approach. The sustainable livelihood approach (SLA) was used as a framework for analyzing and interpreting the data. The students experienced food prices as being high and found food variety at the grocery stores to be low, resulting in struggles to fulfil their food preferences and keep a varied diet. Particularly, social aspects of eating were affected due to high dining prices or inadequate cooking facilities in student homes. However, no student openly reported skipping meals and many mentioned attention for healthy eating. Considering our results, it seems of importance to give more attention to cultural and social aspects related to FI when assessing FI among international students. As the number of international students is increasing, knowing more about this phenomenon can support the promotion of initiatives addressing FI in this population.

Fruit and vegetable consumption and the risk of type 2 diabetes: a systematic review and dose-response meta-analysis of prospective studies

BACKGROUND

The association between intake of fruit and vegetables and their subtypes, and the risk of type 2 diabetes has been investigated in several studies, but the results have been inconsistent.

OBJECTIVE

We conducted an updated systematic review and dose-response meta-analysis of prospective studies on intakes of fruit and vegetables and fruit and vegetable subtypes and the risk of type 2 diabetes.

DESIGN

PubMed and Embase databases were searched up to 20 October 2020. Prospective cohort studies of fruit and vegetable consumption and type 2 diabetes mellitus were included. Summary relative risks (RRs) and 95% CIs were estimated using a random effects model.

RESULTS

We included 23 cohort studies. The summary RR for high versus low intake and per 200 g/day were 0.93 (95% CI: 0.89 to 0.98, I²=0%, n=10 studies) and 0.98 (95% CI: 0.95 to 1.01, I²=37.8%, n=7) for fruit and vegetables combined, 0.93 (95% CI: 0.90 to 0.97, I²=9.3%, n=20) and 0.96 (95% CI: 0.92 to 1.00, I²=68.4%, n=19) for fruits and 0.95 (95% CI: 0.88 to 1.02, I²=60.4%, n=17) and 0.97 (95% CI: 0.94 to 1.01, I²=39.2%, n=16) for vegetables, respectively. Inverse associations were observed for apples, apples and pears, blueberries, grapefruit and grapes and raisins, while positive associations were observed for intakes of cantaloupe, fruit drinks, fruit juice, brussels sprouts, cauliflower and potatoes, however, most of these associations were based on few studies and need further investigation in additional studies.

CONCLUSIONS

This meta-analysis found a weak inverse association between fruit and vegetable intake and type 2 diabetes risk. There is indication of both inverse and positive associations between intake of several fruit and vegetables subtypes and type 2 diabetes risk, however, further studies are needed before firm conclusions can be made.

Effect of nutritional and physical exercise intervention on hospital readmission for patients aged 65 or older: a systematic review and meta-analysis of randomized controlled trials

Background

Unplanned readmission may result in consequences for both the individual and society. The transition of patients from hospital to postdischarge settings often represents a discontinuity of care and is considered crucial in the prevention of avoidable readmissions. In older patients, physical decline and malnutrition are considered risk factors for readmission. The purpose of the study was to determine the effects of nutritional and physical exercise interventions alone or in combination after hospital admission on the risk of hospital readmission among older people.

Methods

A systematic review and meta-analysis of randomized controlled studies was conducted. The search involved seven databases (Medline, AMED, the Cochrane Library, CINAHL, Embase (Ovid), Food Science Source and Web of Science) and was conducted in November 2018. An update of this search was performed in March 2020. Studies involving older adults (65 years and above) investigating the effect of nutritional and/or physical exercise interventions on hospital readmission were included.

Results

A total of 11 randomized controlled studies (five nutritional, five physical exercise and one combined intervention) were included and assessed for quality using the updated Cochrane Risk of Bias Tool. Nutritional interventions resulted in a significant reduction in readmissions (RR 0.84; 95% CI 0.70–1.00, p = 0.049), while physical exercise interventions did not reduce readmissions (RR 1.05; 95% CI 0.84–1.31, p-value = 0.662).

Conclusions

This meta-analysis suggests that nutrition support aiming to optimize energy intake according to patients’ needs may reduce the risk of being readmitted to the hospital for people aged 65 years or older.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12966-021-01123-w.

Older patients' and their family caregivers' perceptions of food, meals and nutritional care in the transition between hospital and home care: a qualitative study

Background

Older people have varying degrees of unmet nutritional needs following discharge from hospital. Inadequate involvement of the older person and his or her family caregivers in care and care planning, and inadequate support of self-management in the discharge process and follow-up care at home, negatively affects the quality of care. Research on older patients’ and their family caregivers’ experiences with nutritional care in hospital and home care and in the transition between these settings is limited. Thus, the aim of this study was to explore older patients’ and their family caregivers’ perceptions regarding the food, meals and nutritional care provided in the transition between hospital and home care services, focusing on the first 30 days at home. The overall aim of this study is to produce knowledge that can inform policy and clinical practice about how to optimise the care provided to older persons that are malnourished or at risk of malnutrition.

Methods

Using a qualitative interpretive descriptive design, we carried out face-to-face semi-structured interviews with 15 older patients, with documented risk of malnutrition or malnourishment (Mini Nutritional Assessment [MNA]), two and five weeks after hospital discharge. In addition, we interviewed nine family caregivers once during this five week period. The questions focused on perceptions of food, meals and nutritional care in hospital and home care and in the transition between these settings. We analysed the data thematically.

Results

Four overarching themes emerged from the material: 1) the need for a comprehensive approach to nutritional care, 2) non-individualised nutritional care at home, 3) lack of mutual comprehension and shared decision making and 4) the role of family caregivers.

Conclusion

The organisation of nutritional care and food provision to older people, depending on care, lack consideration for the individual’s values, needs and preferences. Older patients’ and their family caregivers’ needs and preferences should guide how nutritional care is provided.

Healthcare professionals' experiences of providing individualized nutritional care for Older People in hospital and home care: a qualitative study

Background

Recent studies indicate inadequate nutritional care practices in healthcare institutions and identify several barriers to perform individualized nutritional care to older persons. Organisation of care can become rigid and standardised, thus failing to be respectful of and responsive to each person’s needs and preferences. There is limited research exploring health professionals’ views on how structure of care allows them to individualize nutritional care to older persons. In this study we aim to explore how healthcare professionals’ experience providing individualised nutritional care within the organisational frames of acute geriatric hospital care and home care.

Methods

Semi-structured interviews with 23 healthcare professionals from hospital acute geriatric care and home care. Interviews were analyzed using thematic analysis.

Results

Two main themes and six sub-themes emerged from the material. Theme 1: ‘Meeting patients with complex nutritional problems’ with the sub-themes: ‘It is much more complex than just not eating’ and ‘seeing nutrition as a part of the whole’. Theme 2: ‘The structure of the nutritional care’, with the sub-themes: ‘Nutritional routines: Much ado, but for what?’, ‘lack of time to individualize nutritional care’, ‘lack of interdisciplinary collaboration in nutritional care’ and ‘meeting challenging situations with limited resources in home care’.

Conclusions

The healthcare professionals described having a high focus on and priority of nutritional care when caring for older persons. They did however find it challenging to practice individualized nutritional care due to the complexity of the patients’ nutritional problems and constraints in the way nutritional care was organised. By describing the challenges the healthcare professionals face when trying to individualize the nutritional care, this study may provide important knowledge to health professionals and policy makers on how to decrease the gap between older patients’ preferences for care and nutritional care practice.

Older persons' experiences of adapting to daily life at home after hospital discharge: a qualitative metasummary

Background

Researchers have shown that hospitalisation can decrease older persons’ ability to manage life at home after hospital discharge. Inadequate practices of discharge can be associated with adverse outcomes and an increased risk of readmission. This review systematically summarises qualitative findings portraying older persons’ experiences adapting to daily life at home after hospital discharge.

Methods

A metasummary of qualitative findings using Sandelowski and Barroso’s method. Data from 13 studies are included, following specific selection criteria, and categorised into four main themes.

Results

Four main themes emerged from the material: (1) Experiencing an insecure and unsafe transition, (2) settling into a new situation at home, (3) what would I do without my informal caregiver? and (4) experience of a paternalistic medical model.

Conclusions

The results emphasise the importance of assessment and planning, information and education, preparation of the home environment, the involvement of the older person and caregivers and supporting self-management in the discharge and follow-up care processes at home. Better communication between older persons, hospital providers and home care providers is needed to improve the coordination of care and facilitate recovery at home. The organisational structure may need to be redefined and reorganised to secure continuity of care and the wellbeing of older persons in transitional care situations.

Electronic supplementary material

The online version of this article (10.1186/s12913-019-4035-z) contains supplementary material, which is available to authorized users.

Arsenic in seafood is associated with increased thyroid-stimulating hormone (TSH) in healthy volunteers - A randomized controlled trial

BACKGROUND

Exposure to exogenous elements like arsenic (As) may influence thyroid enzymes, thyroid-stimulating hormone (TSH), and the two principal thyroid hormones, free thyroxine (FT4) and free triiodothyronine (FT3), but little is known about how this is related to organic arsenicals, the main form in seafood.

AIM

To investigate whether a high intake of dietary arsenic from seafood can impact thyroid function and thyroid hormones by examining possible associations with changes in TSH, FT4, FT3 and the FT4:FT3-ratio in plasma.

METHODS

Thirty-eight healthy subjects were randomized into four groups. During a 14-day semi-controlled dietary study, the subjects ingested daily portions of either 150g cod, salmon, blue mussels or potato (control). Plasma concentrations of total As, FT3, FT4, TSH and selenium (Se), and urinary concentrations of iodine were monitored.

RESULTS

Plasma concentrations of TSH increased significantly in all seafood groups. The change in plasma As, with different coefficients for each seafood group, was the dominant factor in the optimal multiple regression model for change in TSH (R²=0.47). Plasma Se and iodine were negative and positive factors, respectively. There were also indications of changes in FT4, FT3 and the FT4:FT3 ratio consistent with a net inhibiting effect of As on FT4 to FT3 conversion.

CONCLUSION

Ingestion of seafood rich in various organic As species was strongly associated with an increase of the TSH concentrations in plasma. Change in TSH was positively associated with total plasma As, but varied with the type of seafood ingested. These findings indicate that organic dietary As, apparently depending on chemical form, may influence thyroid hormones and function.

Lean Fish Consumption Is Associated with Beneficial Changes in the Metabolic Syndrome Components: A 13-Year Follow-Up Study from the Norwegian Tromsø Study

BACKGROUND

Fish consumption may have beneficial effects on metabolic syndrome (MetS); however, limited information of such associations exists. This study investigated possible associations between fish consumption and changes in MetS components during a 13-year follow-up period.

METHODS

The sample included participants (26-69 years) from the Tromsø Study 4 (1994-1995, n = 23,907) and Tromsø Study 6 (2007-2008, n = 12,981). Data were collected using questionnaires including food frequency questions, non-fasting blood samples, and physical examinations. MetS was defined using the Joint Interim Societies (JIS) definition, in which one point was given for each MetS criteria fulfilled (metabolic score). Longitudinal analyses were performed using Linear mixed models.

RESULTS

For both genders, lean fish consumption once a week or more was significantly associated with decreased future metabolic score, decreased triglycerides, and increased high-density lipoprotein (HDL)-cholesterol, whereas decreased waist circumference and blood pressure was identified only for men (age adjusted models). Fatty fish consumption was significantly associated with increased waist circumference for both genders and increased HDL-cholesterol levels in men. Conclusion: The results suggest that fatty and lean fish consumption may influence MetS differently and that lean fish consumption in particular seems to be associated with beneficial changes in the MetS components.

Lean fish consumption is associated with lower risk of metabolic syndrome: a Norwegian cross sectional study

Background

Fish consumption may have a role in reducing the prevalence of metabolic syndrome (MetS). The aim of this study was to identify associations between fish consumption and MetS and its components, especially regarding differences concerning consumption of fatty and lean fish.

Methods

This cross sectional study uses data from the Tromsø 6 survey (2007–08), where a sample of 12 981 adults, aged 30–87 years (47 % men) from the Norwegian general population was included. Fish consumption was assessed using food frequency questionnaires (FFQ). Blood sample assessments, anthropometric and blood pressure measurements were carried out according to standard protocols. MetS was defined using the Joint Interim Societies (JIS) definition. All tests were two-sided. Analyses were performed using IBM SPSS Statistics 22 (Pearson’s correlation, Chi-Square tests, analysis of variance (ANOVA), linear and logistic regression models).

Results

Mean age was 57.5, and the prevalence of MetS was 22.6 %. Fish consumption once a week or more was associated with lower risk of having MetS among men (OR 0.85, CI 95 % 0.74 to 0.98, P = 0.03). In the adjusted models, lean fish consumption was associated with a decreased risk of having MetS, whereas fatty fish consumption was not associated with a decreased risk of having MetS. Both an increased fatty and lean fish consumption (0–1 times per month, 2–3 times per month, 1–3 times per week, 4–6 times per week, 1–2 times per day) were associated with decreased serum triglyceride (TG), and increased high-density lipoprotein cholesterol (HDL-C).

Conclusions

Fish consumption may be associated with a lower risk of having MetS and consumption of lean fish seems to be driving the association. Further investigation is warranted to establish associations between fish consumption and MetS.

Case management at an outpatient unit for severe and enduring eating disorder patients at Stockholm Centre for Eating Disorders- a study protocol

BACKGROUND

Patients with severe and enduring eating disorders (SEED) are seriously ill and have a low quality of life. Case management (CM), originally developed for adult patients with severe mental disabilities, has been shown to enhance social functioning and improve quality of life, while reducing the number and length of hospitalizations. In 2014, a special unit based on CM, for patients with SEED (the Eira unit) was started at Stockholm Centre for Eating Disorders, Sweden.

METHOD/DESIGN

This study aims to investigate if CM can improve SEED patients' quality of life, and reduce their eating disorder symptoms as well as their health care consumption. Methods for data collection are a semi-structured diagnostic interview, self-report questionnaires, and a qualitative interview. The diagnostic interview and the self-report assessments will be done at start of treatment and at follow-ups after 1, 2, and 3years. The qualitative interview will be conducted 1 year after start of treatment. The study is approved by the ethical review board in Stockholm in compliance with the Helsinki Declaration.

DISCUSSION

CM is a possible new contribution to the treatment methods for SEED. It does not aim at remission, but rather to accept life as it is, and to enhance quality of life in the presence of the ED. This study will investigate the potential benefits of this novel intervention in a special unit for SEED patients.

TRIAL REGISTRATION

Clinicaltrials.gov Id: NCT02897622.

Associations between fish consumption and metabolic syndrome. A large cross-sectional study from the Norwegian Tromsø Study: Tromsø 4

BACKGROUND

Fish consumption may prevent or improve metabolic health. The aim of this study was to identify associations between fish consumption, both fatty and lean, and metabolic syndrome and its components.

METHODS

Associations between fish consumption and metabolic syndrome and its components were studied in a large sample from a Norwegian population (N = 23,907), using cross-sectional data from the Tromsø 4 survey (1994-1995). Metabolic syndrome was defined using the JIS definition, and dietary data was collected using food frequency questionnaires (FFQ). Blood samples were taken for biochemical assessments, and anthropometric and blood pressure measurements were carried out according to standard protocols.

RESULTS

In this sample from an adult population (aged 26-70 years, mean age 44 years, SD 11.69, 48 % men), a higher fish consumption (≥1/week) was associated with a healthier lipid profile with increased HDL-C and decreased TG. Participants aged 60-70 years consuming fish once a week or more had significantly lower risk of having MetS, compared to those consuming fish less than once a week (OR 0.64, CI 0.45-0.91). When investigating fatty and lean fish separately, only lean fish consumption was associated with a reduced the risk of having MetS. Participants aged 60-70 years consuming lean fish once a week or more, had lower risk of having MetS compared to those consuming lean fish less than once a week (OR 0.65, CI 0.48-0.87). No association was found for consumption of fatty fish, or for lean fish in the age groups <45 or 45-59 years.

CONCLUSIONS

These results indicates that fatty and lean fish consumption influences MetS risk differently, possibly also related to age. However, further investigation is needed to establish how various fish consumption may influence MetS and its components, particularly when stratified by fatty and lean fish.

In vivo parameters influencing 2-Cys Prx oligomerization: The role of enzyme sulfinylation

2-Cys Prxs are H₂O₂-specific antioxidants that become inactivated by enzyme hyperoxidation at elevated H₂O₂ levels. Although hyperoxidation restricts the antioxidant physiological role of these enzymes, it also allows the enzyme to become an efficient chaperone holdase. The critical molecular event allowing the peroxidase to chaperone switch is thought to be the enzyme assembly into high molecular weight (HMW) structures brought about by enzyme hyperoxidation. How hyperoxidation promotes HMW assembly is not well understood and Prx mutants allowing disentangling its peroxidase and chaperone functions are lacking. To begin addressing the link between enzyme hyperoxidation and HMW structures formation, we have evaluated the in vivo 2-Cys Prxs quaternary structure changes induced by H₂O₂ by size exclusion chromatography (SEC) on crude lysates, using wild type (Wt) untagged and Myc-tagged S. cerevisiae 2-Cys Prx Tsa1 and derivative Tsa1 mutants or genetic conditions known to inactivate peroxidase or chaperone activity or altering the enzyme sensitivity to hyperoxidation. Our data confirm the strict causative link between H₂O₂-induced hyperoxidation and HMW formation/stabilization, also raising the question of whether C_P hyperoxidation triggers the assembly of HMW structures by the stacking of decamers, which is the prevalent view of the literature, or rather, the stabilization of preassembled stacked decamers.

Arsenic in the human food chain, biotransformation and toxicology--Review focusing on seafood arsenic

Fish and seafood are main contributors of arsenic (As) in the diet. The dominating arsenical is the organoarsenical arsenobetaine (AB), found particularly in finfish. Algae, blue mussels and other filter feeders contain less AB, but more arsenosugars and relatively more inorganic arsenic (iAs), whereas fatty fish contain more arsenolipids. Other compounds present in smaller amounts in seafood include trimethylarsine oxide (TMAO), trimethylarsoniopropionate (TMAP), dimethylarsenate (DMA), methylarsenate (MA) and sulfur-containing arsenicals. The toxic and carcinogenic arsenical iAs is biotransformed in humans and excreted in urine as the carcinogens dimethylarsinate (DMA) and methylarsonate (MA), producing reactive intermediates in the process. Less is known about the biotransformation of organoarsenicals, but new insight indicates that bioconversion of arsenosugars and arsenolipids in seafood results in urinary excretion of DMA, possibly also producing reactive trivalent arsenic intermediates. Recent findings also indicate that the pre-systematic metabolism by colon microbiota play an important role for human metabolism of arsenicals. Processing of seafood may also result in transformation of arsenicals.

Fish consumption and its possible preventive role on the development and prevalence of metabolic syndrome - a systematic review

Metabolic syndrome (MetS) has a huge impact on public health, and today lifestyle interventions remain the primary mode for MetS therapy. It is therefore important to elucidate the possible preventive effects of diet and foods, and their MetS-related health implications. To examine how fish consumption affects the development and prevalence of MetS, we systematically reviewed cross-sectional, prospective cohort, and intervention studies conducted among adults (humans) and, reporting consumption of fish or seafood as being related to MetS (prevalence or incidence), where MetS was defined via an established definition. The literature search in PubMed identified 502 citations, and after screening, 49 full-text articles were retrieved and assessed for eligibility. After excluding duplicates and those not meeting the inclusion criteria, seven studies from Croatia, Finland, France, Iceland, Iran, Korea, and US were included. Four studies (one follow-up and three cross-sectional) found associations between fish consumption and MetS (three among men, and one among women), suggesting that fish consumption may prevent or improve metabolic health and have a protective role in MetS prevention. This protective role might be related to gender, and men may benefit more from the consumption of fish. However, lack of controlling for potential confounders may also inflict the results. Additional research is required to further explore fish consumption and its potential role in improving or reversing MetS and its components.

Effect of different degrees of hydrogenated fish oil on intestinal carcinogenesis in Min/+ mice

Intake of trans fatty acids from hydrogenated fish oils has been related to increased risk of coronary heart diseases. The possible effect on colorectal carcinogenesis is unclear.

MATERIALS AND METHODS

Multiple intestinal neoplasia (Min/+) mice were fed one of four experimental diets: either raw fish oil (FO), low (LHFO)-, high (HHFO)- or fully-hydrogenated fish oil (FFHO), from 0 to 9 weeks of age. The number and size of intestinal tumors were recorded.

RESULTS

There was no difference between the intervention groups in the numbers of developed intestinal tumors. The tumor size was statistically significantly lower in HHFO vs. the FO-group in male Min/+ mice. The HHFO and FHFO groups had lower weight gain than did the FO group (p=0.008 and p=0.04, respectively), but gender differences, due to effect of dietary intervention on weight gain, were found in Min/+ mice.

CONCLUSION

When compared with raw fish oil, different degrees of hydrogenation of the fish oil had no effect on intestinal carcinogenesis in Min/+ mice.

Humans seem to produce arsenobetaine and dimethylarsinate after a bolus dose of seafood

Seafood is the predominant food source of several organoarsenic compounds. Some seafood species, like crustaceans and seaweed, also contain inorganic arsenic (iAs), a well-known toxicant. It is unclear whether human biotransformation of ingested organoarsenicals from seafood result in formation of arsenicals of health concern. The present controlled dietary study examined the urinary excretion of arsenic compounds (total arsenic (tAs), iAs, AB (arsenobetaine), dimethylarsinate (DMA) and methylarsonate (MA)) following ingestion of a single test meal of seafood (cod, 780 μg tAs, farmed salmon, 290 μg tAs or blue mussel, 690 μg tAs or potato (control, 110 μg tAs)) in 38 volunteers. The amount of ingested tAs excreted via the urine within 0-72 h varied significantly among the groups: Cod, 74% (52-92%), salmon 56% (46-82%), blue mussel 49% (37-78%), control 45% (30-60%). The estimated total urinary excretion of AB was higher than the amount of ingested AB in the blue mussel group (112%) and also ingestion of cod seemed to result in more AB, indicating possible endogenous formation of AB from other organoarsenicals. Excretion of iAs was lower than ingested (13-22% of the ingested iAs was excreted in the different groups). Although the ingested amount of iAs+DMA+MA was low for all seafood groups (1.2-4.5% of tAs ingested), the urinary DMA excretion was high in the blue mussel and salmon groups, counting for 25% and 11% of the excreted tAs respectively. In conclusion our data indicate a possible formation of AB as a result of biotransformation of other organic arsenicals. The considerable amount of DMA excreted is probably not only due to methylation of ingested iAs, but due to biotransformation of organoarsenicals making it an inappropriate biomarker of iAs exposure in populations with a high seafood intake.

Effects of an eight-month weight-control program on body composition and lipid oxidation rate during exercise in obese children

OBJECTIVE

To investigate the effects of an 8-month multidisciplinary weight-control program, including 2 h/week of moderate physical activity, nutritional education lessons and psychological follow-up, on body composition and lipid oxidation rate during exercise in obese children.

DESIGN

Nineteen (7 boys and 12 girls) obese children, aged 8-12 yr [mean body mass index (BMI) z-score: 2.3 and fat mass: 35.8%] participated in this study. Before and at the end of the weight-control period body composition was assessed by bioelectrical impedance, lipid oxidation rate by indirect calorimetry during a graded exercise test, and time devoted to various activities and energy intake in free-living conditions by questionnaire.

RESULTS

All children completed the study, at the end of which BMI decreased significantly by mean 0.6+/-0.5 and 0.5+/-0.8 kg/m2, in boys and girls, respectively (p<0.05), and fat mass (FM) decreased by 1.7+/-2.8 and 1.4+/-1.3 kg in boys and girls, respectively (p<0.05). In addition, lipid oxidation rate during exercise increased significantly throughout the graded exercise test up to 21% at maximal lipid oxidation rate which happened at 48+/-5% of maximal oxygen uptake (VO2max), corresponding to 64+/-5% of maximal heart rate. Time spent at sedentary and very light physical activities decreased (p<0.001) to the benefit of recreational activities at home.

CONCLUSIONS

Multidisciplinary weight-control program, with moderate-intensity physical activities, induced decreases in FM without decreases in free FM, increases in VO2max, lipid oxidation rate during exercise, and time devoted to recreational activities in free-living conditions.

Bond strength of luting materials to ceramic crowns after different surface treatments

The aim of present study was to evaluate the effect of different pre-treatments of alumina and zirconia copings on the bond strength of different luting materials. Pull out tests was performed on 60 alumina and 80 zirconia copings. Randomly selected, copings were divided in groups of i) un-treated alumina and zirconia copings, (n=20) ii) alumina and zirconia copings sandblasted with 50 or 110 microm alumina particles respectively (n=20), iii) zirconia copings treated with monolayer of glass pearls fused to the inner surface (n=20), iv) zirconia copings treated with silanized glass pearls (n=10). Zinc phosphate, Panavia 21 and VarioLink II were used for cementation. Pull out tests were done in an Instron universal testing machine with a speed of 0.5 mm/min and fracture loads was measured in N. Untreated zirconia copings cemented with zinc phosphate showed significantly higher bond strength values compared to those with sandblasted surfaces. No difference was seen between untreated alumina copings and those with sandblasted surfaces. Sandblasting decreased bond strength of zirconia and alumina copings. Glass pearls increased bond strength of zirconia copings, which was even better after silanization. Variolink II in combination with alumina gave significantly lower bond strength.

Surface roughness of five different dental ceramic core materials after grinding and polishing

In clinical practice, core materials can be exposed after adjustments are made to previously-luted all-ceramic restorations. The purpose of this study was to evaluate the surface roughness of five different dental ceramic core materials after grinding and polishing. Five different ceramic core materials, Vita In-Ceram Alumina, Vita In-Ceram Zirconia, IPS Empress 2, Procera AllCeram, and Denzir were evaluated. Vita Mark II was used as a reference material. The surface roughness, Ra value (mum), was registered using a profilometer. The measurements were made before and after grinding with diamond rotary cutting instruments and after polishing with the Sof-Lex system. The surface of representative specimens was evaluated qualitatively using scanning electron microscopy (SEM). Results were statistically analysed using analysis of variance (anova) supplemented with Scheffè's and Bonferroni multiple-comparison tests. Before grinding, Procera AllCeram and Denzir had the smoothest surfaces, while IPS Empress 2 had the coarsest. After grinding, all materials except IPS Empress 2 became coarser. Polishing with Sof-Lex provided no significant (P > 0.05) differences between Denzir, Vita Mark II and IPS Empress 2 or between Procera AllCeram and In-Ceram Zirconia. There were no significant differences (P > 0.05) either between the ground and the polished Procera AllCeram or In-Ceram Alumina specimens. Polishing of Denzir, IPS Empress 2 and In-Ceram Zirconia made the surfaces smoother compared with the state after grinding, whereas the polishing effect on Procera AllCeram and In-Ceram Alumina was ineffective. The findings of the SEM evaluation were consistent with the profilometer readings.

Adenovirus vector designed for expression of toxic proteins

To construct recombinant adenoviruses expressing biologically active proteins may be impossible, or result in a significant reduction in virus yield, if the protein expressed has an inhibitory effect on virus replication or cellular growth. To overcome this problem, we previously designed adenovirus vectors expressing foreign proteins from inducible promoters. However, during our work with a replication-deficient virus expressing the ASF/SF2 splicing factor from a progesterone antagonist-inducible gene cassette, we discovered that ASF/SF2 was expressed at a significant level in the 293 producer cell line, even in the absence of inducer. 293 cells code for adenovirus E1A and E1B proteins and thus support the growth of E1-deficient adenoviruses. Here we show that this background ASF/SF2 expression results from a low level of E1A-mediated transactivation of the basal promoter driving transgene expression. To overcome the problem of leaky expression, we reconstructed a novel gene cassette that combines an inducible promoter and a Lac repressor protein-based block to reduce transcriptional elongation. We show that this novel vector system dramatically reduced background transgene expression and therefore should be useful for the rescue and propagation of high-titer stocks of recombinant adenoviruses expressing toxic proteins.

Cisplatin induces the proapoptotic conformation of Bak in a deltaMEKK1-dependent manner

In a panel of four human melanoma cell lines, equitoxic doses of cisplatin induced the proapoptotic conformation of the Bcl-2 family protein Bak prior to the execution phase of apoptosis. Because cisplatin-induced modulation of the related Bax protein was seen in only one cell line, a degree of specificity in the signal to Bak is indicated. Little is known about upstream regulation of Bak activity. In this study, we examined whether the apoptosis-specific pathway mediated by a kinase fragment of MEKK1 (DeltaMEKK1) is involved in the observed Bak modulation. We report that expression of a kinase-inactive fragment of MEKK1 (dominant negative MEKK [dnMEKK]) efficiently blocked cisplatin-induced modulation of Bak and cytochrome c release and consequently also reduced DEVDase activation and nuclear fragmentation. Accordingly, expression of a kinase-active MEKK1 fragment (dominant positive MEKK) was sufficient to induce modulation of Bak in three cell lines and to induce apoptosis in two of these. dnMEKK did not block cisplatin-induced c-Jun N-terminal kinase (JNK) activation, in agreement with a specifically proapoptotic role for the DeltaMEKK1 pathway. Finally, we show that reduction of Bak expression by antisense Bak reduced cisplatin-induced loss of mitochondrial integrity and caspase cleavage activity in breast cancer cell lines. In summary, we have identified Bak as a cisplatin-regulated component downstream in a proapoptotic, JNK-independent DeltaMEKK1 pathway.

Intestinal fatty acid binding protein polymorphism at codon 54 is not associated with postprandial responses to fat and glucose tolerance tests in healthy young Europeans. Results from EARS II participants

Polymorphism Ala54Thr of the intestinal fatty acid-binding protein 2 (FABP2) has been reported to have an effect on the protein's affinity for long chain fatty acids and to be associated with serum lipid and insulin levels in fasting and especially postprandial states. We wanted to test whether this genetic variation is associated with fasting and postprandial glucose, insulin or lipid levels in 666 male university students participating in the second European Atherosclerosis Study (EARS II). We also studied whether the subgroup of 330 students with paternal history of myocardial infarction (MI) before the age of 55 have different genotype distribution than 336 matched controls.

RESULTS

No difference in genotype distribution was observed between offspring with and without paternal history of MI or between populations from 11 European countries. The frequency of the threonine encoding allele was 0.276 in cases and 0.266 in controls. There were no differences in fasting or postprandial serum lipid, glucose or insulin levels between subjects having different genotypes.

CONCLUSIONS

In this study FABP2 Ala54Thr polymorphism was not associated with lipid or glucose metabolism. In addition to environmental and genetic factors, selection of study population also may explain the difference between this and earlier studies.

Increased apoptosis and increased clonogenic survival of 12V-H-ras transformed rat fibroblasts in response to cisplatin

Mutationally activated Ras is involved in tumor progression and likely also in drug resistance. Using survival, viability and apoptosis assays, we have here compared the cisplatin sensitivities of FR3T3 rat fibroblasts and a 12V-H-ras transformed subline (Ras2:3). Around 24 h after cisplatin treatment Ras2:3 cells showed higher apoptosis levels and lower viability than FR3T3. This increased sensitivity correlated with weaker cisplatin-induced activation of Jun N-terminal kinase (JNK). In contrast to apoptosis assays, colony formation assays showed that Ras2:3 were more resistant to cisplatin than were FR3T3. This was partly due to the increased cisplatin sensitivity of FR3T3 seeded at low densities, as required in colony formation assays. In addition, Ras2:3 cisplatin survivors had a higher relative proliferative capacity. Cell cycle analyses showed that FR3T3 cells initially responded with a dose-dependent G2 arrest, while Ras2:3 accumulated in S-phase. Experiments with an anti-apoptotic mutant of MEKK1 suggested that the apoptotic response of Ras2:3 cells is not specific to the S-phase fraction. In summary, the cisplatin response of ras-transformed fibroblasts is distinct from that of parental cells, in that they show increased apoptosis, a different cell cycle response and increased post-treatment proliferative capacity. The results illustrate the need to carefully consider methods and protocols for in vitro studies on chemotherapy sensitivity.

Overexpression of essential splicing factor ASF/SF2 blocks the temporal shift in adenovirus pre-mRNA splicing and reduces virus progeny formation

Expression of cytoplasmic mRNA from most adenovirus transcription units is subjected to a temporal regulation at the level of alternative pre-mRNA splicing. The general tendency is that splice site selection changes from proximal to distal late after infection. Interestingly, ASF/SF2, which is a prototypical member of the SR family of splicing factors, has the opposite effect on splice site selection, inducing an increase in proximal splice site usage. We have previously shown that SR proteins late during an adenovirus infection become partially inactivated as splicing regulatory proteins. A prediction from these results is that overexpression of an SR protein, such as ASF/SF2, during virus growth will interfere with virus replication by disturbing the balance of functional and nonfunctional ASF/SF2 in the infected cell. To test this hypothesis, we reconstructed a recombinant adenovirus expressing ASF/SF2 under the transcriptional control of a regulated promoter. The results show that, as predicted, induction of ASF/SF2 during lytic virus growth prevents the early to late shift in mRNA expression from both early (E1A and E1B) and late (L1) transcription units. Furthermore, ASF/SF2 overexpression blocks viral DNA replication and reduces selectively cytoplasmic accumulation of major late mRNA, resulting in a lower virus yield. Collectively, our results provide additional support for the hypothesis that viral control of SR protein function is important for the proper expression of viral proteins during lytic virus growth.

Interrelationships between low density lipoprotein receptor defect, serum fatty acid composition, and serum cholesterol concentration

It is known that, in the general human population, serum fatty acid composition is correlated with serum triacylglycerol and cholesterol concentrations. The goal of the present study was to analyze whether the same is true of individuals who have a low density lipoprotein receptor (LDL-R) defect. Concentrations of 16 different fatty acids, cholesterol, triacylglycerol, and major lipoproteins in serum were determined in eight individuals who had (FH-North Karelia), the most common LDL-R defect in Finland, which causes familial hypercholesterolemia, and in their 30 relatives belonging to a single large pedigree as controls. The average number of double bonds (i.e., degree of desaturation) in serum fatty acids correlated negatively with the concentrations of serum total cholesterol (r = 0.27, P < 0.05) and total triacylglycerol (r = -0.71, P < 0.001) and positively with the number of fish meals per week (r = 0.50, P < 0.01), which was analyzed in all pedigree members jointly. These effects were similar in individuals having LDL-R defect, in which group the correlation coefficients were -0.31 (P = NS), -0.99 (P < 0.001), and 0.79 (P = NS) for serum total cholesterol, triacylglycerol, and weekly fish meals, respectively. Thus, LDL-R defect does not impair the correlation between serum fatty acid composition and serum triacylglycerol concentration. This result is in agreement with dietary studies that have shown that familial hypercholesterolemia patients respond very favorably to dietary therapy.

A 5-year clinical evaluation of ceramic inlays (Cerec) cemented with a dual-cured or chemically cured resin composite luting agent

Sixty-six class-II CAD/CAM-manufactured ceramic inlays (Cerec) were placed in 27 patients. Each patient received at least one inlay luted with a dual-cured resin composite and one inlay luted with a chemically cured resin composite. The inlays were examined 5 years after luting using the California Dental Association (CDA) criteria. Eighty-nine percent of the 66 inlays were rated 'satisfactory'. During the follow-up period replacement was required for 3 inlays because of inlay fractures (4.5%) and 1 inlay because of fracture of the tooth substance (1.5%). All those inlays were luted with the dual-cured resin composite luting agent. Of the remaining 62 inlays the CDA rating 'excellent' was given to 84% for color, 97% for surface, and 81% for anatomic form. 'Excellent' margin integrity was seen in 52% of the dual-cured resin composite luted inlays and in 61% of the chemically cured resin composite luted inlays. No statistically significant (P> 0.05) difference was observed between the two luting agents.

Two novel adenovirus vector systems permitting regulated protein expression in gene transfer experiments

Two new adenovirus vector systems based on the tetracycline-regulated Tet-ON- (Gossen, M., et al., Science 268:1766-1769, 1995) and the RU 486-regulated progesterone antagonist (Wang, Y., et al., Proc. Natl. Acad. Sci. USA 91:8180-8184, 1994)-induced gene expression systems are described. We show that both systems permit a tight control of chloramphenicol acetyltransferase reporter gene expression in a variety of cell types, with induction levels of approximately 1,800-fold (Tet-ON system) and 600-fold (RU 486-regulated system), respectively. A significant advantage of our vector systems is that reporter protein expression can be adjusted over a wide range by varying the amount of inducer. The Tet-ON system is also shown to permit an efficient control of reporter gene expression in mice.

A meta-analysis of implants in partial edentulism

A meta-analytic technique was used to estimate the survival of implants supporting bridges or single crowns in partially edentulous patients. A survey of the literature revealed 66 studies, published between 1986 and 1996. Nine studies on single implants and 10 studies on fixed partial dentures met the inclusion criteria for the meta-analysis. Data from a total of 2686 implants, 570 single crowns (SC) and 2116 in fixed partial dentures (FPD), were analyzed. In order to calculate annual survival rates for individual studies a life-table analysis was conducted. Maximum follow-up time ranged between 1 and 8 years. After 1 year the success rate was calculated to be at least 85.7% for FPD and 97.2% for SC. When the results from the FPD studies were pooled the survival rate was 93.6% after 6-7 years. The corresponding value for SC was 97.5%.

Mercury levels in plasma and urine after removal of all amalgam restorations: the effect of using rubber dams

OBJECTIVE

The aim of the present study was to determine whether removal of all amalgam restorations might significantly affect mercury levels in plasma and urine and whether the use of rubber dams might reduce patient exposure to mercury during amalgam removal.

METHODS

All amalgam restorations were removed from 18 subjects during a single treatment session in which a rubber dam was used and from 10 subjects when a rubber dam was not used. All amalgam restorations were removed by the same dentist using high-speed cutting, water coolant, and high-volume evacuation. The levels of mercury in plasma and urine were analyzed both before and during the subsequent twelve months after amalgam removal. In order to determine whether removal of all amalgam restorations might cause an exposure large enough to significantly increase the mercury levels in two indicator media for mercury exposure, i.e., plasma and urine, and to determine if the removal might cause a significant decrease in the mercury levels found over time, the one-tailed, paired Students' t-test was used. For each individual, the pre-removal levels were compared with both the levels found in plasma on d 1 and in urine on d 10, and also with the levels found 1 y after removal. Furthermore, in order to examine whether the use of rubber dams had any effect on the mercury levels found after removal, the changes in the mercury levels found were compared between the groups using the Wilcoxon-Mann-Whitney rank sum test.

RESULTS

After removal of all amalgam restorations, only the non-rubber dam group showed significant increases in the mercury levels found in plasma (p = 0.012) and urine (p = 0.037). However, one year later, the mercury levels in plasma and urine had sunk significantly below the pre-removal levels for both groups. When the changes in the mercury levels found were compared between the groups, the non-rubber dam group showed a significantly higher increase of mercury in plasma than the rubber dam group the day after removal (p = 0.0010). Compared to the pre-removal mercury levels in plasma and urine, the levels found 1 y after removal of all amalgam restorations were on average 52 +/- 23% (range 4-89%) lower in plasma and 76 +/- 21% (range 20-94%) lower in urine.

SIGNIFICANCE

The study showed that dental amalgam had a statistically significant impact on the mercury levels found in plasma and urine in the patients tested, and that the use of a rubber dam during removal of all amalgam restorations significantly reduced the peak of mercury in plasma following removal.

Long-term clinical results after treatment with conical crown-retained dentures

The clinical outcome of treatment using conical crown-retained dentures was evaluated. Of the initial 25 patients provided with 26 conical crown-retained dentures, 18 patients with 18 restorations could be examined after a time ranging between 73 and 92 months. Of the eight restorations lost, four had been changed as a result of factors that might have been related to the prosthodontic care. Most of the patients were very satisfied with the restorations both functionally and esthetically and found their chewing comfort to be better after treatment with conical crown-retained dentures. However, 50% of the patients reported speech problems related to treatment. Technical failures were not insignificant but were treatable. The survival rate after 73 to 92 months was 78.3%.

A 3-year clinical follow-up study of a ceramic (Optec) inlay system

To evaluate the clinical quality of ceramic (Optec) inlays, the inlay production of 10 dentists, served by 3 dental laboratories, was examined independently by 2 calibrated examiners. Of the 57 patients with 205 inlays participating in the first examination, 47 patients with 145 remaining inlays participated in the 3-year follow-up reexamination. For 14 of the participants in the reexamination, altogether 21 inlays had fractured. The mean time in service before fracture was 26.4 months (range, 12-53 months). The inlays were rated using the California Dental Association (CDA) quality evaluation system. This examination showed that the mismatch of color had increased from the first examination to the reexamination and registered slightly roughened surfaces. As to anatomic form, a reduced number of inlays did not receive an excellent CDA rating at the reexamination. Visible evidence of ditching along the margin had increased by almost 50%, and an apparent discoloration of the margin between the restoration and the tooth structure was seen in 73% of the reexamined inlays, compared with 7% at the first examination.

Mercury vapor release from dental amalgam in patients with symptoms allegedly caused by amalgam fillings

The aim of this study was to determine whether a group of patients with symptoms, self-related to their amalgam restorations, experienced an exposure to mercury vapor from their amalgam restorations that reached the range at which subtle symptoms have been reported in the literature. Furthermore, the aim was to determine whether the mercury exposure for these patients was significantly higher than for controls with no reported health complaints. The symptom group consisted of 10 consecutively selected patients from a larger group, referred by their physicians for investigation into any correlation between subjective symptoms and amalgam restorations. The control group consisted of 8 persons with no reported health complaints. The intra-oral release of mercury vapor was measured between 7:45 a.m. and 9:00 p.m. at intervals of 30-45 min, following a standardized schedule. The mercury levels in plasma, erythrocytes, and urine were also determined. The calculated daily uptake of inhaled mercury vapor, released from the amalgam restorations, was less than 5% of the daily uptake calculated at the lower concentration range given by the WHO (1991), at which subtle symptoms have been found in particularly sensitive individuals. The symptom group had neither a higher estimated daily uptake of inhaled mercury vapor, nor a higher mercury concentration in blood and urine than in the control group. The study provides no scientific support for the belief that the symptoms of the patients examined originated from an enhanced mercury release from their amalgam restorations.

Ceramic inlays (Cerec) cemented with either a dual-cured or a chemically cured composite resin luting agent. A 2-year clinical study

On the basis of the criteria of the California Dental Association (CDA), 66 CAD/CAM-manufactured ceramic class-II inlays (Cerec) were compared intraindividually after they had been cemented with either a chemically cured or a dual-cured composite resin luting agent in 27 patients. Plaque and gingival conditions, the overall time consumption for producing each inlay, and the frequency of postoperative sensitivity were also evaluated. There was no statistically significant difference between the two luting agents with regard to the properties evaluated. One inlay was replaced owing to fracture of the restored tooth just before the 24-month re-examination. After 2 years excellent CDA ratings were obtained for color in 92% of the remaining 65 inlays. The corresponding figures for surface and for anatomic form were 100% and 85%, respectively. For margin integrity 85% of the 33 inlays cemented with the dual-cured luting agent and 88% of the 33 inlays cemented with the chemically cured luting agent were rated excellent after 2 years.