Biomedical subjects

D Holst

Publications and source records attributed to D Holst.

At least 19 recordsLinked to original sources

PubMed2006

Inter-individual variation in the plaque formation rate of young individuals.

OBJECTIVES: The aim of the present study was to describe the inter-individual variation in the plaque formation rate of 38 young adults. METHODS: The plaque formation rate was estimated by employing a quantitative plaque percent index (P% index). A substantial inter-individual variation in the plaque formation rate was observed. The possible contributions of stimulated salivary flow rate, buffer capacity, diet and smoking to the variation in plaque formation were estimated by regression analysis. RESULTS: The control variables explained only 2.5% of the variance in the plaque formation rate. Neither associations nor the total model were significant. The present method of measuring plaque presented as a simple and time-effective procedure. CONCLUSIONS: It is suggested that the observed variation in the plague formation rate between the young individuals can be regarded as a biological function which is possibly an inherent individual characteristic. Studies with larger sample sizes are required to confirm the findings of the present study.

Adolescent↗

PubMed2001

Utility of chest computed tomography for staging in patients with T1 extremity soft tissue sarcomas.

BACKGROUND: National Cancer Center Network (NCCN) and Society of Surgical Oncology (SSO) practice guidelines recommend chest computed tomography (CT) as part of the staging evaluation of patients with extremity soft tissue sarcoma (STS). In the current study, the authors evaluated the use and yield of chest roentgenography (CXR) and selective chest CT to screen for pulmonary metastases in patients with T1 STS. METHODS: The utility of these staging studies was evaluated retrospectively in a cohort of 125 consecutive patients who presented to a tertiary care cancer center with T1 primary (nonrecurrent) extremity STS. Two diagnostic strategies (CXR alone vs. CXR plus chest CT) were evaluated using an incremental cost-effectiveness ratio. RESULTS: The majority of tumors (70%) were high grade. The median sarcoma size was 3.0 cm; 64 of the tumors (51%) were located deep to the investing fascia of the extremity. All patients underwent staging CXR; 1 CXR (< 1%) was suspicious for metastatic disease. Fifty-one patients (41%) also underwent chest CT; 1 chest CT, performed in the patient with a suspicious CXR, revealed metastatic disease. With a median follow-up of 76 months, 19 patients (15%) developed metachronous pulmonary metastases. The relatively low yield resulted in an incremental cost-effectiveness ratio of $59,772 per case of synchronous pulmonary metastasis detected by CXR plus chest CT. CONCLUSIONS: Less than 1% of patients with T1 primary extremity STS were found to have pulmonary metastases that were detectable using a staging algorithm that employs routine CXR with the selective use of chest CT. The findings of the current study do not support current NCCN or SSO practice guidelines for patients with high-grade T1 STS.

Adolescent↗

PubMed2001

Acyl-CoA esters antagonize the effects of ligands on peroxisome proliferator-activated receptor alpha conformation, DNA binding, and interaction with Co-factors.

The peroxisome proliferator-activated receptor alpha (PPARalpha) is a ligand-activated transcription factor and a key regulator of lipid homeostasis. Numerous fatty acids and eicosanoids serve as ligands and activators for PPARalpha. Here we demonstrate that S-hexadecyl-CoA, a nonhydrolyzable palmitoyl-CoA analog, antagonizes the effects of agonists on PPARalpha conformation and function in vitro. In electrophoretic mobility shift assays, S-hexadecyl-CoA prevented agonist-induced binding of the PPARalpha-retinoid X receptor alpha heterodimer to the acyl-CoA oxidase peroxisome proliferator response element. PPARalpha bound specifically to immobilized palmitoyl-CoA and Wy14643, but not BRL49653, abolished binding. S-Hexadecyl-CoA increased in a dose-dependent and reversible manner the sensitivity of PPARalpha to chymotrypsin digestion, and the S-hexadecyl-CoA-induced sensitivity required a functional PPARalpha ligand-binding pocket. S-Hexadecyl-CoA prevented ligand-induced interaction between the co-activator SRC-1 and PPARalpha but increased recruitment of the nuclear receptor co-repressor NCoR. In cells, the concentration of free acyl-CoA esters is kept in the low nanomolar range due to the buffering effect of high affinity acyl-CoA-binding proteins, especially the acyl-CoA-binding protein. By using PPARalpha expressed in Sf21 cells for electrophoretic mobility shift assays, we demonstrate that S-hexadecyl-CoA was able to increase the mobility of the PPARalpha-containing heterodimer even in the presence of a molar excess of acyl-CoA-binding protein, mimicking the conditions found in vivo.

Acyl Coenzyme A↗

PubMed2001

Oral status indicators DMFT and FS-T: reflections on index selection.

Oral status in a population has traditionally been described by the DMFT index (decayed, filled, and missing teeth). There seems to be contradicting and confusing evidence in the literature with regard to the usefulness of different indices. Limitations of the DMFT are recognised, and attempts have been made to develop other indices. Two indices, DMFT and FS-T (filled and sound teeth) have been selected for analysis in the present paper. The purpose of this paper is to examine the relationship between DMFT and FS-T in different populations, and to show consequences of choice of index exemplified in analytical analysis. Data stem from the Trondelag-83 and -94 studies that were follow-up studies of the Norwegian portion of the 1973 International Collaborative Study. Sunflower scatter plots and regression analyses were used to describe the variation in DMFT and FS-T in different populations. DMFT was more suitable for describing variation in populations with low levels of disease than FS-T, while FS-T was more suitable for describing variation in populations with high levels of disease. It may be concluded that both DMFT and FS-T should be presented when describing oral status in a population. However, choice of index depends first of all on the purpose of the investigation. If there are theoretical reasons to prefer one index instead of the other, the superiority of the alternative index in terms of variation must be disregarded.

Adult↗

PubMed2001

Caries in populations--a theoretical, causal approach.

The focus of this paper is caries in populations. Caries is assessed as a phenomenon and as it occurs in populations. It is observed that in recent literature the notion of causation of caries is restricted to the biological process on the tooth surface. This may be sufficient to explain caries as a phenomenon, but it is argued that a biological causation is insufficient in order to understand caries and its variation in populations. The understanding of the determinants of a population's oral health has been seriously impeded by the absence of a theoretical framework. A framework would be useful to the extent that it would bridge relevant categories for portraying complex causal patterns of caries in populations. An approach to a framework has therefore been outlined, and the idea of such a framework has been confronted with three critical comments. The framework is as yet pragmatic, incomplete, uncertain and fragmented. Yet, even such an approach may invite greater precision in epidemiological concepts about causes of caries than presently prevails. The framework directs attention to health effects of collective phenomena that cannot be reduced to individual attributes. The image proposed in this paper is intended to spur discussion about important aspects of the epidemiology of caries in populations.

Attitude to Health↗

PubMed2001

An "S-shaped" relationship between smoking duration and alveolar bone loss: generating a hypothesis.

BACKGROUND: A number of epidemiological studies have shown that smoking is a risk factor for periodontal disease. Little is known about the relationship between smoking duration and alveolar bone loss. The purpose of this research was to describe the prevalence of alveolar bone loss according to smoking status in Norway. A dose-response model for duration of tobacco smoking on alveolar bone loss was then developed and discussed. METHODS: The study population consisted of 812 individuals living in Norway aged 45 to 64 years old (248 current smokers, 245 former smokers and 319 non-smokers). Alveolar bone loss was measured on bite-wing radiographs. Simple descriptive statistics were used to describe the central tendency and variation in alveolar bone loss. Regression analyses were performed to study the relationship between smoking duration and alveolar bone loss. RESULTS: Mean alveolar bone loss varied between 1.51 mm and 2.64 mm depending on smoking status and age. Mean alveolar bone loss was lowest in non-smokers and highest in current smokers. Given identical smoking status, the mean alveolar bone loss increased with increasing age except for the 2 oldest age groups of current smokers. CONCLUSIONS: Our results generate the hypothesis that the relationship between smoking duration and alveolar bone loss was "S-shaped." Assuming that alveolar bone loss is irreversible after smoking cessation, it could be hypothesized that there is a threshold period for tobacco smoking after which the accumulated effect of smoking becomes clinically observable. After a certain number of years of smoking, the effect on alveolar bone loss seems to level out. To test this hypothesis, the relationship between smoking duration and alveolar bone loss should be studied in a prospective study design.

Age Factors↗

PubMed2001

[Postoperative nausea and vomiting--still a problem?].

Based on a questionnaire of the General Hospital of Hamburg-Altona, we asked 738 patients about postoperative complaints such as nausea, vomiting, pain in the operating field and feeling of coldness in order to record the quality of the results of operation and anaesthesia in 1997 and 1998. The incidence of nausea and vomiting amounted to only 29% on average. One of our earlier studies of postoperative vomiting from 1995-1997 and the results gained from a control group of non-treated patients in our ondansetron study from 1995, which was conducted using information drawn from the routinely-used anaesthesia protocol and was therefore limited to data from the immediate pre- and postoperative period up to discharge of the patients from the recovery ward, showed much higher frequencies of nausea and vomiting (44 and even 66% on average, respectively). We cannot definitely evaluate whether the reduction in the average rates of nausea and vomiting in our present study is due to the additional preoperative application of 150 mg vomex supp. and 1.0-2.5 mg dehydrobenzperidol and/or 20-30 mg metoclopramid given i.v. shortly before the end of anaesthesia or to more intensive observation of non-medicinal prophylactic possibilities. But when we look at the frequency of nausea and vomiting in special groups of our present study, we can still find unacceptably high rates of nausea and vomiting, for instance 40% after cholecystectomies and abruptios and even 50% after struma operations. This shows that a satisfactory solution to this problem has not yet been found--partly due, unfortunately, to financial restrictions. Nevertheless, for 15% of the patients postoperative nausea and vomiting were of only minor importance for general satisfaction with the treatment given them. This was probably due to good premedication of amnestic after-effects of narcosis.

Adolescent↗

PubMed2000

Alterations of peroxisome proliferator-activated receptor delta activity affect fatty acid-controlled adipose differentiation.

Fatty acids have been postulated to regulate adaptation of adipose mass to nutritional changes by controlling expression of genes implicated in lipid metabolism via activation of nuclear receptors. Ectopic expression of the nuclear receptors PPARgamma or PPARdelta promotes adipogenesis in fibroblastic cells exposed to thiazolidinediones or long-chain fatty acids. To investigate the role of PPARdelta in fatty acid regulation of gene expression and adipogenesis in a preadipose cellular context, we studied the effects of overexpressing the native receptor or the dominant-negative PPARdelta mutant in Ob1771 and 3T3-F442A cells. Overexpression of PPARdelta enhanced fatty acid induction of the adipose-related genes for fatty acid translocase, adipocyte lipid binding protein, and PPARgamma and fatty acid effects on terminal differentiation. A transactivation-deficient form of PPARdelta mutated in the AF2 domain severely reduced these effects. Findings are similar in Ob1771 or 3T3-F442A preadipose cells. These data demonstrate that PPARdelta plays a central role in fatty acid-controlled differentiation of preadipose cells. Furthermore, they suggest that modulation of PPARdelta expression or activity could affect adaptive responses of white adipose tissue to nutritional changes.

3T3 Cells↗

PubMed2000

Mobile workstation for anaesthesia and intensive-care medicine.

Our mobile monitoring and treatment station, for use in anaesthesia and intensive care, allows transport of patients around the medical unit without disconnection from medical equipment, with a maximum level of safety, and low workload and costs.

Anesthesiology↗

PubMed2000

Oral health changes in an adult Norwegian population: a cohort analytical approach.

OBJECTIVES: The purpose of this analysis was to study temporal variation in oral health in an adult population. The cohort analysis comprised 1) estimation of longitudinal, cross-sectional, and time-lag differences in caries and treatment experience of the adult population in Trøndelag from 1973 to 1983 and to 1994; 2) assessment of which of the effects of age, period and cohort was the most plausible explanation for the observed differences and 3) discussion of causal and other factors underlying the effects of age, period and cohort. METHODS: Cohort analysis was used to study changes in oral health over time. Study participants were selected by random sampling in 1973, 1983, and 1994 (n = 1959, n = 3195, n = 2341 respectively). The methods of data collection comprised standardised clinical measurements and a self-administered questionnaire. Cohort tables were established to analyse changes in DFT from 1973 to 1983 and DFT and DFS from 1983 to 1994. RESULTS: Four patterns of changes in oral health were identified from adolescence to older adulthood. They point in different directions which indicate that complex processes are present. There were two and three significant changes in the subsets of analysis. Assumptions and conditions that allow identification of separate cohort, period, and age effects appeared not to be present. The pattern of changes was consistent with main effects of both age, period, and cohort. The effects were discussed from the perspective of the chosen frame of explanatory factors. CONCLUSIONS: The changes in oral health between populations in 1973, 1983 and 1994 were the combined consequences of simultaneously occurring factors that account for both age, period and cohort effects.

Adolescent↗

PubMed2000

Variation in caries and treatment experience in 35-44-year-old Lithuanians.

Data summarising caries levels differ between countries and often conceal large variations. These differences may reflect variations at individual, group, social and other levels. Caries and treatment experience differences are found to be significantly related to a variety of clinical and non-clinical factors. Variation in caries within Lithuanian children has been reported and related to background-, behavior-, dental care- and other factors. Variation in general or related to any factors in adult Lithuanian population has not been studied. The aim of the present study was to estimate variation in caries and treatment experience and relate them to biological-, psychosocial-, health-related, behavioral- and dental care related aspects. The existing knowledge from other oral health studies was used to select the factors found of importance in relation to variations in caries scores. The study consisted of clinical and self-reported data collected from a stratified random sample of 382 individuals (attendance rate 50%). Two statistical approaches, a bivariate and a multivariate, were applied. The two dependent variables DMFT and DS were tested with a set of independent variables. The bivariate analysis revealed significant associations for approximately one half of all variables studied. For multivariate testing, a backward linear multiple regression was used. Forty-one percent of the variation in DS was explained and 48% in DMFT scores. Differences in scores were related to various factors in the two analyses. The strength and significance of a few relationships differed in both of the analyses. The multivariate testing revealed some strong and significant associations with independent variables which were found to be weak and non-significant (P>0.05) when tested bivariately and vice versa. Less than half of the variation could be explained in dental caries scores in 35-44-year-olds and not only dental care related factors were important. In both of the analyses, the varying degrees of strength (significance levels) give rise to a hypothesis that this incomplete explanation of the variation can be due to interrelated effects of different estimates.

Adult↗

PubMed2000

Patterns of dental caries and treatment experience in elderly Lithuanians.

OBJECTIVE: The aim of the study was to evaluate patterns of caries experience in a representative sample of Lithuanians, aged 65-74. METHODS: This cross-sectional study included 301 participants (response rate 54%). Information was obtained from a clinical examination (caries experience, stimulated salivary flow rates and oral hygiene levels) and a questionnaire. The questionnaire comprised questions about oral, general, physical, mental and social health and about background, knowledge, attitudes and lifestyle. The study had a multidimensional approach to negative consequences of disease and positive aspects of health. For bivariate testing, t-test, ANOVA and Spearman's correlation were used. Factor analysis was combined with linear multiple regression for a multivariate study of caries experience patterns. RESULTS: Elderly Lithuanians were found to have lower levels of edentulousness (range 11-15%) than elderly people in other European countries. The mean number of missing teeth was also lower than in any of the neighbouring countries. A comparison of dentate and edentulous groups did not show any major differences. Those who reported that they had general disease had higher levels of oral health maintenance. In dentate elderly, caries experience differed according to place of residence, fluoride content in the drinking water, socioeconomic status, gender, lifestyle, and many other factors. The multivariate approach explained 52%, 61% and 55% of the variation in the number of filled or sound teeth (FS-T), decayed (DT) and missing teeth (MT) respectively. CONCLUSION: Levels of oral health maintenance and caries experience show substantial variation among elderly Lithuanians, according to many health-related characteristics. These elderly people require appropriate oral care, just as much as people in other population sub-groups.

Aged↗

PubMed2000

[Practical realization of a patient-accompanying concept in anesthesia and intensive care].

UNLABELLED: Our current concept of stationary workplaces results in an interruption in patient monitoring and treatment. Because transfers are invariably associated with a reduction or interruption in the monitoring and treatment chain, an endangerment to critically-ill patients, as well as a significant increase in the mortality rates, can result. DESIGN: In the new construction of the Cardiac Clinic, the previous concept of immobile anesthesia and intensive care workstations has been completely abandoned. The complete treatment workstation, including monitoring and fluid management, is set up on a bedside cart which accompanies the patients uninterruptedly--from anesthesia administration, to the operating room, to the ICU or recovery room, as well as during elective or emergency interventions outside the ICU. Transport times and complications from 995 transports (ASA III and IV) were analysed and compared with 880 transports with the conventional system. RESULTS: During all intrahospital transfers with the mobile workplace, there were no complications resulting from faulty operation or accidental adjustment of the perfusors, or from disconnecting the monitoring,-, respiration-, or infusion lines. On the whole, there were fewer cases of circulatory instability during transport, since infusion treatment and medication could be administered without interruption. All hemodynamic parameters were recorded during transport, as were cardiac minute output and right- and left-atrial filling pressures. The mobile workplace system allows for the shortest possible transport and exchange times--13.5 min, as compared to 42.5 min with the conventional system. The reconnection of monitoring equipment with zeroing, adjustment of the alarm limits, as well as exchanging perfusors and infusomats before and after transport is eliminated entirely. CONCLUSION: This mobile workplace, in which all components of the anesthesiological and intensive care workstations are integrated, guarantees the highest possible level of patient safety, since nothing has to be disconnected until the patient is transferred to a normal-care ward. In addition to the improved ergonomic design of the nurse's and doctor's workplace, substantial savings can also be made.

Anesthesia↗

PubMed1999

Expression of peroxisome proliferator-activated receptor PPARdelta promotes induction of PPARgamma and adipocyte differentiation in 3T3C2 fibroblasts.

Nutritional long chain fatty acids control adipose tissue mass by regulating the number and the size of adipocytes. The molecular mechanisms implicated in this action of fatty acids remain poorly understood. It has been well established that peroxisome proliferator-activated receptor (PPAR) gamma, activated by specific prostanoids, plays a central role in the control of adipocyte gene expression and terminal differentiation. Thus far, the role of PPARdelta in the control of adipose tissue mass has remained unclear. Herein, we report the effects of ectopically expressed PPARdelta on the control of adipose-related gene expression and adipogenesis of 3T3C2 fibroblasts. Treatment of PPARdelta-expressing fibroblasts with fatty acids alone did not stimulate adipogenesis, whereas exposure of cells to a combination of fatty acids and PPARgamma activators promoted lipid accumulation and expression of a typical adipocyte program. At the molecular level, activation of PPARdelta by fatty acids induced transcription of the genes encoding fatty acid transporter, adipocyte lipid-binding protein, and PPARgamma. Subsequent activation of PPARgamma by specific agonists appeared to be required to promote terminal differentiation. These data demonstrate that PPARgamma gene expression is under the control of PPARdelta activated by fatty acids and could explain, at least partially, the adipogenic action of nutritional fatty acids.

3T3 Cells↗

PubMed1999

Continuous spinal anaesthesia or continuous epidural anaesthesia for post-operative pain control after hip replacement?

Both continuous spinal anaesthesia and continuous epidural anaesthesia are supposed to provide adequate post-operative pain relief. The purpose of this randomized, prospective study was to compare the quality of analgesia, occurrence of side effects and patient satisfaction between spinal and epidural administration of bupivacaine during the first post-operative 72 h. One hundred and two patients scheduled for hip arthroplasty were randomly assigned to one of two groups: Group 1 received continuous spinal anaesthesia for intra-operative and post-operative management, Group 2 received continuous epidural anaesthesia. Immediately after surgery, the continuous spinal anaesthesia-group received a 1-mL bolus (bupivacaine 0.25%), followed by a continuous infusion of 10 mL over 24 h. The continuous epidural anaesthesia-group received a 10-mL bolus (bupivacaine 0.25%), followed by 2 mL h-1. The level of pain was gauged from a verbal rating score and from a visual analogue scale; the degree of motor blockade was recorded using the Bromage score. In the continuous spinal anaesthesia-group 90.2% reported complete analgesia on the verbal rating scale, but only 21.6% of the continuous epidural anaesthesia-group did. The visual analogue scale scores given by the continuous spinal anaesthesia-group were significantly lower than those of the continuous epidural anaesthesia-group. The percentage of patients with a motor block was significantly higher in the continuous spinal anaesthesia-group on the day of surgery and at the first post-operative day. During the first 24 h, nausea and vomiting occurred more often in the continuous epidural anaesthesia-group. The satisfaction was considered excellent in 92.2% of the continuous spinal anaesthesia-group and in 70.6% of the continuous epidural anaesthesia-group. It is concluded that continuous spinal anaesthesia and continuous epidural anaesthesia are effective and safe for post-operative pain relief after hip replacement. Compared with continuous epidural anaesthesia, continuous spinal anaesthesia provides faster onset of pain relief, ensures better analgesia and results in more satisfied patients.

Aged↗

PubMed1999

Validity of a questionnaire survey: the role of non-response and incorrect answers.

Errors in questionnaire surveys are usually of one of two sources: non-responses or incorrect answers. The aim was to investigate the validity of a questionnaire survey and to estimate the respective bias of these answers. Of 9,283 subjects selected to receive a questionnaire by post, 3,949 (43%) responded, and, of these, 3,400 correctly reported their Swedish social security number. Answers in the questionnaire survey were given as proportions of the claims registered at local insurance offices. In the group of respondents who had correctly reported their social security number, the answers were compared individually with the registrations in dental insurance claims. In Sweden, these claims are labeled with the patient's social security number and it is thereby possible to make such comparisons. It was shown that errors were caused by non-response and also by respondents giving incorrect answers. Incorrect answers accounted for approximately one-third of the total bias. The remaining bias was caused by a non-response error. It is concluded that questionnaire studies have a bias caused by both non-response and incorrect answers and that together these can be substantial. Scientific reports that include questionnaire surveys must describe the procedure carefully. If possible, other sources of information should be considered.

Bias↗

PubMed1999

Adjusting estimates of alveolar bone loss for missing observations: developing and testing a general model.

The occurrence of missing teeth is a vexing and growing problem in epidemiological studies of dental disease. The number of units of measurement (i.e., teeth/tooth sites) varies between persons and may affect summary statistics in descriptive studies as well as in analytical studies. The purpose of the present study was to develop a general model to adjust summary statistics for missing teeth. The proposed method was applied to alveolar bone loss in current smokers, former smokers, and non-smokers, from 45 to 64 years of age (n = 812). Alveolar bone loss was measured on bitewing radiographs. The adjustment method was based on the assumption that the probability of losing a tooth was an increasing function of alveolar bone loss. The main finding of the present study was that mean alveolar bone loss increased after adjustment for the number of missing teeth. This increase was larger for current smokers than for non-smokers, indicating that the effects of smoking were slightly underestimated when missing sites were ignored. Further research is required for the model to be applied to other data, estimating different types of dental disease with various degrees of disease prevalence and various numbers of missing teeth, and for validating the adjustment method by means of longitudinal data.

Age Factors↗

PubMed1999

Dental care of young adults in west Sweden.

107 Swedish subjects, all 20 years old, were studied for the first three years (1990-1992) after they had left the organised dental care for children and adolescents (which is free of charge for all youth through the age of 19). They were registered in four different risk-grouping systems in order to estimate the amount of their future dental care. Three of the systems used registrations from the Public Dental Service records and in the fourth one a dentist made a subjective estimation. The follow-up used dental insurance claims to study performed treatments, courses of treatments and cost. The risk group system that used subjective estimations appeared to be the one that most accurately predicted the actual dental care consumption. Approximately 70% of the subjects received some kind of dental care during the three years. The distribution was not confined to any particular risk group. Ten per cent had received complete dental care annually. Twenty-five per cent went to a private dentist and 75% continued to go to the Public Dental Service. Those who went to a private dentist received substantially more treatment and the annual cost was a little more than twice as much as in the Public Dental Service.

Adult↗