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R Holle

Publications and source records attributed to R Holle.

At least 19 recordsLinked to original sources

Differential association of adiponectin with cardiovascular risk markers in men and women? The KORA survey 2000.

BACKGROUND: In men, high adiponectin concentrations were related to a lower risk of myocardial infarction, whereas no association with cardiovascular events was found in women. OBJECTIVE: To investigate sex differences in the associations of adiponectin with cardiovascular risk factors. DESIGN: Cross-sectional population-based KORA Survey 2000 in Southern Germany using the same study methods for cardiovascular risk factors as the former WHO MONICA project. PARTICIPANTS: A total of 697 men and 657 women, aged 55-74 years. Glucose tolerance status was assessed by oral glucose tolerance tests. RESULTS: Adiponectin (geometric mean, interquartile range; microg/ml) levels were significantly higher in women (11.1; 8.5-14.9) than in men (7.1; 5.2-9.6) (P<0.05). In univariate analyses, HDL-cholesterol and age were significantly positively correlated with adiponectin in both sexes. Negative correlations were observed with BMI, waist circumference, fasting and postchallenge glucose, insulin, HOMA-IR, HbA1c, triglycerides, uric acid and CRP (P<0.01). In sex-specific multivariate regression, age and HDL-cholesterol were independently positively, and fasting insulin and 2-h glucose were negatively related to adiponectin in both sexes. Uric acid was significantly inversely related to adiponectin in women only (sex interaction: P=0.02). Exploratory sex-specific factor analysis of adiponectin and the core components of the metabolic syndrome yielded four similar factors. Adiponectin loaded negatively on the 'lipids' factor in both sexes. CONCLUSION: The associations of adiponectin with cardiovascular risk factors showed a similar pattern in both sexes, except for uric acid. This small sex difference may not explain previous conflicting results on the association of adiponectin with cardiovascular events in men and women.

Adiponectin↗

[Quality of care and extent of complications in a population-based sample of patients with type 2 diabetes mellitus. The KORA Survey 2000].

BACKGROUND AND OBJECTIVE: The aim of this study was to analyse health care processes and outcomes in type 2 diabetes in a representative population sample of persons, aged 25-74 years, in the region of Augsburg, Germany. PATIENTS AND METHODS: Based on the KORA Survey 2000, indicators of health care services and outcomes were analysed for all study subjects with known type 2 diabetes (n=149; 80 males (54%)) , mean age 62 +/- 9 years; total random population sample: 4,261 persons). Means and prevalences were calculated, including 95% confidence intervals (CI). Associated factors were analysed using multivariate regression models. RESULTS: 57% of the patients had not received adequate drug treatment concerning hypertension and 43% concerning hypercholesterolemia. 63% (CI: 54-70 %) and 38% (CI: 30-47%), respectively, reported that their eyes or feet had been examined during the past 12 months. 47% (CI: 39-56%) had been instructed about their diabetes. 69% (CI: 61-76%) of the subjects did not know the term "HbA(1c)", the proportion being higher among subjects without diabetes education or those of a low social status. 13% (CI: 8-20%) of the subjects had been told by their medical practitioner that they had a retinopathy, 5% (CI: 2- 10%) a foot ulcer, 19% (CI: 12-28%) proteinuria. Two persons were blind, one had been on renal dialysis, and 5% (CI: 2-10%) had undergone amputation of a limb. 6% (3-12%) had at least one of the end-stage diabetic complications. The mean HbA(1c) was 7.2 +/- 1.6%, significantly higher in those with a diabetes for >10 years. CONCLUSIONS: The population-based data regarding indicators of type 2 diabetes care processes and outcome in a defined region in Germany show that the treatment of hypertension and hypercholesterolemia was highly inappropriate, as was the frequency of medical control investigations. The high proportion of subjects who did not know the term "HbA(1c)" was striking, particularly among those of a low social status. A significant proportion had severe late complications. The mean HbA(1c), however, was better than had been reported in some previous German practice-based studies.

Adult↗

Sex differences in the associations of socioeconomic status with undiagnosed diabetes mellitus and impaired glucose tolerance in the elderly population: the KORA Survey 2000.

BACKGROUND: Sex differences in the associations of socioeconomic status (SES) with prevalence of undiagnosed diabetes mellitus, impaired glucose tolerance (IGT) and known risk factors of type 2 diabetes mellitus were investigated in an elderly population. METHODS: Oral glucose tolerance tests were carried out in 1354 randomly selected subjects (697 men, 657 women) aged 55-74 years in the population-based KORA Survey 2000, Augsburg, Germany. Odds ratios (ORs) and 95% confidence intervals (CIs) for undiagnosed diabetes or IGT by education, occupation and income were estimated using logistic regression controlling for age, waist circumference, blood pressure, triglycerides, physical activity, smoking and alcohol intake. RESULTS: All three SES variables were significantly inversely related to body mass index, waist circumference and low physical activity in women (P < 0.05). In men, these associations were weaker or absent. Using the lowest category as reference, occupational status was significantly associated with undiagnosed diabetes in women (adjusted OR 0.5; 95% CI 0.3-0.8) after controlling for risk factors in multivariate regression. The OR was also reduced with higher income in women (adjusted OR, diabetes: 0.7; 95% CI 0.5-1.03). Among men, no significant relations of the SES indicators with unknown diabetes were observed. However, the odds of having IGT was lower with higher occupational status in men (adjusted OR 0.7; 95% CI 0.5-0.9). CONCLUSIONS: Undiagnosed type 2 diabetes was related to low SES defined by occupation or income in women only. In men, low occupational status was independently associated with higher IGT risk. Educational level was not related to glucose disorders in both sexes in the elderly population.

Aged↗

The diabetes epidemic in the elderly population in Western Europe: data from population-based studies.

Valid epidemiologic data on type 2 diabetes in the elderly population are scarce in the European Region despite its enormous human and economic burden. The aim was to assess population-based data on type 2 diabetes and impaired glucose regulation (IGR) from surveys carried out in Western Europe since 1990 using oral glucose tolerance tests, and to discuss the possible impact of risk factors on geographic variation, in particular, obesity and physical activity. In the decade below 60 years of age, about 10 % of the population had known or newly diagnosed diabetes in European surveys. In the age group 70 to 79 years, average total diabetes prevalence was about one quarter. IGR prevalences also increased with age, reaching a maximum of 25 % (men) to 30 % (women) above 70 years of age. There was a wide variation of total diabetes prevalence in the elderly population in Western European countries, however, without clear geographical pattern. Whereas age- and sex-specific prevalences for total diabetes in the German KORA Survey S4 (1999/2001) (Augsburg) were comparable to the European average, IGR prevalences were higher in Augsburg (60-69 years: KORA: men: 30.2 %, women: 22.4 % Europe: men: 21.2 %, women: 19.0 %). Thus, there is a huge reservoir for future diabetes cases in the elderly population in Germany. Differences at the population level were found for obesity, nutrition, and sedentary lifestyle in Western Europe. Comparative studies on the predictive values of obesity, physical activity, and nutrition and possible interactions with genetic markers in European populations are of interest in the future.

Age Distribution↗

Cost-effectiveness of type 2 diabetes screening: results from recently published studies.

Type 2 diabetes screening is recommended by various international diabetes associations. We conducted a literature research to identify and describe systematically recently published cost effectiveness analyses (CEA) for type 2 diabetes screening. Three analyses were included. One of them was conducted in Germany, based on the data of the KORA survey S4 (1999/2001). Two studies came from the US. The German as well as one of the US studies evaluated cost per detected diabetic case as main outcome. In contrast to the US study, the German study considered incomplete participation in the screening programs as baseline case. HbA1 c testing combined with the oral glucose tolerance test (OGTT) was more expensive than OGTT or fasting glucose testing, but also most effective in detecting cases, due to high participation in this screening strategy. The second US study investigated the lifetime cost effectiveness of type 2 diabetes screening, based on a Markov model to calculate cost per quality-adjusted life year (QALY). Effectiveness data were derived from two large intervention studies in clinically diagnosed (not identified by screening) diabetic subjects. The authors conclude that type 2 diabetes screening is cost effective, in particular targeted screening in elderly hypertensive subjects. Diabetes screening may be cost effective. However, the effectiveness of early detection and treatment of type 2 diabetes has not yet been shown, and data regarding the course of early detected diabetes are lacking so far. In the future, the most important question is whether type 2 diabetes screening and early treatment is effective with respect to clinical outcomes.

Adult↗

KORA--a research platform for population based health research.

KORA (Cooperative Health Research in the Region Augsburg) is a regional research platform for population-based surveys and subsequent follow-up studies in the fields of epidemiology, health economics, and health care research. KORA was established in 1996 to continue and expand the MONICA project in Augsburg, including the Acute Myocardial Infarction (AMI) Registry. The available pool of study participants allows for cohort, case-control and family studies. We present the KORA infrastructure, aspects of data management and quality control, and the concept of cooperative research. The increasing use of the MONICA/KORA cohorts for a variety of research topics, with a recent focus on genetic epidemiology, indicates the attractiveness of this concept.

Adult↗

Inflammation and type 2 diabetes: results from KORA Augsburg.

Type 2 diabetes is associated with a systemic low-grade inflammation. First data provided by cross-sectional studies from as early as the 1960s demonstrated elevated systemic levels of glycoproteins and acute-phase reactants and increased leukocyte counts in type 2 diabetes patients. Subsequently, prospective studies showed that elevated concentrations of several acute-phase proteins and cytokines are predictive of later type 2 diabetes. Immune gene variants in man and in animal models were found to affect insulin resistance and diabetes incidence. Antidiabetic treatment by medication, diet or physical activity results in a significant decrease of systemic immune mediator concentrations. Immunological analyses of the KORA Survey S4 (1999/2001) allowed us to show that levels of circulating acute-phase proteins like CRP and of IL-6 are highly correlated and associated not only with overt type 2 diabetes, but already with impaired glucose tolerance (IGT) pointing out a role of these mediators in the pathogenesis of type 2 diabetes. On the contrary, TNFalpha was neither coregulated with CRP nor associated with diabetes status. Our study therefore shows that type 2 diabetes is accompanied by a non-random and differential upregulation of components of the innate immunity and suggests that this inflammatory condition is involved in the aetiology of the disease. Future work will extend the range of analysed immune mediators to chemokines and will also investigate the association of immune markers with indices of obesity to elucidate the relevance of this traditional risk factor for low-grade inflammation.

Acute-Phase Proteins↗

[Disease management programmes in Germany: first reactions by patients suffering from diabetes].

The performance of health delivery for chronic diseases in Germany has been considered deficient for a long time and in need of improvement. The launch of Disease Management Programmes (DMP) for type 2 diabetes in the summer of 2002 can be seen as an attempt to optimise health care for the chronically ill. The aim of our study was to find out at an early stage of DMP development which factors, personal or otherwise, would have an influence on whether diabetic patients know of, and are willing to participate in, such a programme. The data of 679 diabetic patients, collected between late 2002 and the end of 2003, presented here have been extracted from a written follow-up study to the three baseline surveys S1 (1984/85), S2 (1989/90) und S3 (1994/95) in Augsburg as part of the WHO-MONICA project with more than 13,000 participants. The study population is characterised by a rather high age (mean: 67.4 years), a long duration of the disease (mean: 9.8 years) as well as a high intensity of contacts with physicians. Only 28 % of the diabetic patients had heard of the DMP, but a majority of the participants (54 %) stated their readiness to participate in DMP once offered. Higher age, low education as well as no participation in diabetes education have been identified in logistic regression models as impeding factors both for the knowing of and the participation in DMP. As a consequence, promotion of the DMP should be directed to those sections of the diabetic population outside the effective reach of the traditional diabetes care organisations.

Adult↗

Genetics of type 2 diabetes: impact of interleukin-6 gene variants.

The KORA studies serve as a powerful tool for the genetic analysis of complex diseases like type 2 diabetes or the metabolic syndrome. These studies include more than 2,000 prevalent and incident type 2 diabetes cases. DNA of these patients is available to be used in genetic studies. Up to now the analyses have focussed on genes coding for proteins being involved in the inflammatory response. Interleukin-6 (IL-6) as the key mediator of the acute phase reaction is of interest. Elevated protein concentrations of IL-6 in the blood have been shown to predict type 2 diabetes. We investigated the association of the IL-6 single nucleotide polymorphism (SNP) C-174G with type 2 diabetes in a case-control study of 704 elderly participants of the KORA Survey S4 (1999/2001). When BMI, HDL cholesterol, physical activity, hypertension, hormone replacement therapy and smoking were considered as covariables the SNP C-174G showed a trend for association with type 2 diabetes (- 174G: OR 1.20, 95 % CI 0.90 - 1.59, p = 0.21).

Adult↗

Association of humoral immunity to human Hsp60 with the IL-6 gene polymorphism C-174G in patients with type 2 diabetes and controls.

The relationship between humoral immunity to hsp60 and type 2 diabetes along with other relevant metabolic, inflammatory and immunogenetic variables was studied in 76 non-diabetic and 74 diabetic persons aged 55-74 years selected from the population-based KORA Survey 2000. Antibodies to human hsp60 were measured in serum samples by ELISA. Hsp60 antibodies were detected in all but two individuals in a considerable range of titres (22-1,856 AU/ml). There was no significant association to age and sex, or to key clinical or metabolic parameters (BMI, WHR, HbA1c, total cholesterol, LDL cholesterol, HDL cholesterol, systolic and diastolic blood pressure, albumin, uric acid) or immunological parameters (CRP, IL-6, sIL-6R, TNFalpha, sTNFalpha R60, sTNFalpha R80). Analysis of antibody-positive individuals revealed an association between hsp60 antibodies and diabetes at borderline significance (p = 0.047), which was lost when the two antibody-negative individuals were included. Genetic analyses indicated that this association was significant in carriers of the C allele of the IL-6 promoter region polymorphism at nucleotide -174 (p = 0.02), but not in GG genotype carriers. We conclude that humoral immunity to human hsp60 may be enhanced in those diabetic patients carrying the -174C allele of the IL-6 gene. This finding may contribute to an understanding of the relationship between the -174C allele and increased risk of atherosclerosis.

Aged↗

Association study of mast cell chymase polymorphisms with atopy.

BACKGROUND: Atopic disorders are the result of complex interactions between genetic and environmental factors. Associations analyses between the promoter polymorphism rs1800875 in the mast cell chymase gene (CMA1) and atopy-related phenotypes have yielded inconsistent results. METHODS: We sequenced the CMA1 locus in 24 unrelated healthy individuals with serum IgE levels <50% percentile and 24 individuals with atopic eczema and serum IgE levels >90% percentile. Seven CMA1 single nucleotide polymorphisms (SNPs) were evaluated for evidence of associations with atopic phenotypes within a large population of German adults (n = 1875). Subjects were phenotyped by standardized questionnaires and interviews, skin prick testing and serum IgE measurements. Genotyping was performed using MALDI-TOF MS (Matrix-Assisted Laser Desorption Ionization-Time of Flight mass spectrometry). RESULTS: Promoter polymorphism rs1800875 was significantly associated with atopic eczema. No associations between any other single SNP and atopic phenotypes could be detected. Haplotype reconstruction revealed four of 128 possible haplotypes reaching estimated frequencies of 3% or more. Two of these haplotypes showed a borderline-significant association with atopic eczema, which did not remain significant after correction for multiple testing. CONCLUSIONS: Results confirm previous observations of a significant association between the CMA1 promoter polymorphism rs1800875 and atopic eczema, but not with serum IgE levels, and support the hypothesis that CMA1 serves as candidate gene for atopic eczema.

Chymases↗

[The problem of response in epidemiological studies in Germany (part I)].

To achieve high response rates in German epidemiological studies is growing more difficult. Low response in epidemiological studies may decrease the acceptance of the results. Response, however, is not identical with the quality of a study. In the first part of this paper various definitions of response (contact, cooperation, response, recruitment proportions) are introduced and discussed in the context of different study designs with reference to practical examples. A population-based survey such as the Study of Health in Pomerania (SHIP) investigates the distribution of risk factors and health-related endpoints. Surveys should yield representative results which can be generalised to apply to the entire population (external validity). This study design usually requires large participitation proportions. In a prospective cohort study such as the European Investigation into Cancer and Nutrition (EPIC) the emphasis is on internal validity. A stable study population willing to participate in regular follow-ups is a primary recruitment goal. If the response in a case-control study such as the Northern Germany Leukaemia and Lymphoma Study (NLL) is low, the priority is to achieve approximately equal response proportions for cases and controls. Simultaneous public relation and media activities can improve participitation in a study. Multidimensional strategies combining public communications, cooperation with local and regional officials and frequent press and media coverage are emphasised. The second part of this paper will discuss methods to quantify the effects of the response proportions on the validity of the study results.

Adult↗

Significant association of the interleukin-6 gene polymorphisms C-174G and A-598G with type 2 diabetes.

Elevated blood concentrations of IL-6 have been shown to predict type 2 diabetes. Because the impact of IL-6 gene polymorphisms on diabetes status, parameters of the metabolic syndrome, and low-grade systemic inflammation has not been analyzed in a population-based study, we investigated the association of the IL-6 single nucleotide polymorphisms C-174G and A-598G on these parameters in 704 elderly participants of the Kooperative Gesundheitsforschung im Raum Augsburg/Cooperative Research in the Region of Augsburg (KORA) Survey 2000. Both -174G and -598G alleles were significantly associated with type 2 diabetes (-174G: odds ratio = 1.51, 95% confidence interval = 1.11-2.07, P = 0.0096; -598G: odds ratio = 1.56, 95% confidence interval = 1.13-2.15, P = 0.0069) but not with impaired glucose tolerance. In subgroup analyses, the association reached statistical significance in men and in leaner subjects (body mass index <or= 28.7 kg/m(2), i.e. study median) but not in women or more obese persons. Circulating IL-6 levels were not associated with the IL-6 polymorphisms, but significantly elevated levels of the chemokine monocyte chemoattractant protein-1/CC chemokine ligand 2 in carriers of the protective genotypes indicated an indirect effect of these single nucleotide polymorphisms on the innate immune system. Our findings confirm that immune gene polymorphisms can be considered as independent risk factors in the etiology of type 2 diabetes and suggest that their contribution may be indirect, by influencing the levels of other immune mediators like monocyte chemoattractant protein-1.

Adult↗

High prevalence of undiagnosed diabetes mellitus in Southern Germany: target populations for efficient screening. The KORA survey 2000.

AIMS/HYPOTHESIS: To estimate the prevalence of undiagnosed diabetes mellitus, impaired glucose tolerance (IGT) and impaired fasting glucose (IFG), and their relations with cardiovascular risk factors in the general population aged 55 to 74 years in Southern Germany. METHODS: Oral glucose tolerance tests were carried out in a random sample of 1353 subjects aged 55 to 74 years participating in the KORA (Cooperative Health Research in the Region of Augsburg) Survey 2000. Prevalences of glucose tolerance categories (1999 WHO criteria) were adjusted for sample probabilities. The numbers needed to screen (NNTS) to identify one person with undiagnosed diabetes were estimated from age-adjusted logistic regression models. RESULTS: Sample design-based prevalences of known and unknown diabetes, IGT, and IFG were 9.0%, 9.7%, 16.8%, 9.8% in men, and 7.9%, 6.9%, 16.0%, 4.5% in women, respectively. In both sexes, participants with undiagnosed diabetes had higher BMI, waist circumference, systolic blood pressure, triglycerides, uric acid, and lower HDL-cholesterol than normoglycaemic subjects. A combination of abdominal adiposity, hypertension, and parental diabetes in men resulted in a NNTS of 2.9 (95%CI: 2.0-4.6). In women, the combination of increased triglycerides, hypertension and parental diabetes history yielded a NNTS of 3.2 (95%CI: 2.2-5.1). CONCLUSION/INTERPRETATION: About 40% of the population aged 55 to 74 years in the Augsburg region have disturbed glucose tolerance or diabetes. Half of the total cases with diabetes are undiagnosed. Cardiovascular risk factors worsen among glucose tolerance categories, indicating the need for screening and prevention. Screening for undiagnosed diabetes could be most efficient in individuals with abdominal adiposity (men), hypertriglyceridaemia (women), hypertension, and parental diabetes history.

Aged↗

Incidence and prevalence of juvenile arthritis in an urban population of southern Germany: a prospective study.

OBJECTIVE: To ascertain the incidence and prevalence of juvenile arthritis in a German urban population. METHODS: All 766 paediatricians, orthopaedists, and rheumatologists working in practices or outpatient clinics in 12 south German towns were asked to report all patients who consulted them for juvenile arthritis during the year 1995. Patients with continuing symptoms were followed up for 9-12 months to obtain a final diagnosis. Extended measures of quality control were taken to control for known biases. RESULTS: Of 457 reported cases, 294 were diagnosed with para-/postinfectious arthritis (PPA), 78 with juvenile chronic arthritis (JCA), and 18 with other forms of arthritis. Half of the PPA cases were classified as transient synovitis of the hip (SH). For JCA the reported annual incidence was 6.6 and the prevalence 14.8 per 100 000 subjects under 16 years of age. For PPA the reported incidence was 76 and the prevalence 4.4 per 100 000 subjects under 16. The incidence of rheumatic fever was clearly below 1 per 100 000 people under 16. A correction model was used to control for known biases and to adjust the estimates accordingly. CONCLUSIONS: The results of this first prospective study on the incidence and prevalence of juvenile arthritis in Germany are consistent with a retrospective study performed in the Berlin area. Based on these results it was estimated that the annual frequency of juvenile arthritis in Germany is as follows: 750-900 incident JCA cases, 21 000 incident SH cases, and 21 000 incidence cases of other forms of PPA a year. The number of incidence cases of rheumatic fever is expected to be markedly lower than 150 a year. The total prevalence is expected to be 3600-4350 JCA cases, 2250-3000 SH cases, and the same number of other forms of PPA.

Adolescent↗

Long-term results of guided tissue regeneration therapy with non-resorbable and bioabsorbable barriers. I. Class II furcations.

BACKGROUND: The aim of this 5-year follow-up study was to clinically and radiographically evaluate the long-term results after guided tissue regeneration (GTR) therapy of Class II furcation defects using non-resorbable and bioabsorbable barriers. METHODS: Nine pairs of contralateral Class II furcation defects were treated in 9 patients with advanced periodontitis. Within each patient, one defect received a non-resorbable (expanded polytetrafluoroethylene [ePTFE]; control, C) barrier and the other a bioabsorbable (polyglactin 910; test, T) barrier by random assignment. At baseline, 6, and 60 +/- 3 months after surgery, clinical parameters and standardized radiographs were obtained. Gain of bone density within furcation areas was assessed using subtraction radiography. RESULTS: Six and 60 months after GTR therapy, statistically significant (P <0.05) horizontal attachment (CAL-H) gain was observed in both groups (C6: 1.7 +/- 0.8 mm; C60: 1.6 +/- 1.2 mm; T6: 2.0 +/- 0.7 mm; T60: 2.2 +/- 0.9 mm). However, 1 furcation assessed as Class I six months after GTR therapy with a bioabsorbable barrier had progressed to Class III after 5 years, and in another patient, 5 years after placement of an ePTFE barrier, 1 furcation had lost all the CAL-H gain that had been observed at 6 months. Subtraction analysis revealed similar area gain in both groups 6 and 60 months postsurgically (C6: 0.3 +/- 0.5; C60 1.0 +/- 1.7; T6: 0.4 +/- 0.4; T60: 1.1 +/- 1.7). CONCLUSIONS: CAL-H gain achieved after GTR therapy in Class II furcations was stable after 5 years in 16 of 18 defects. The study failed to show a statistically significant difference in stability of CAL-H gain between control and test groups 5 years after GTR therapy.

Absorbable Implants↗

Radiographic defect depth and width for prognosis and description of periodontal healing of infrabony defects.

BACKGROUND: The aims of the present study were to evaluate 1) defect depth and width as a prognostic factor and 2) change in defect width as a describing parameter of periodontal healing in infrabony defects treated by regenerative therapy after 6 and 24 months. METHODS: In 24 patients with advanced periodontitis, 39 infrabony defects were treated by guided tissue regeneration (GTR) using expanded polytetrafluoroethylene (ePTFE) (n = 7) or bioabsorbable barriers (n = 32). Clinical parameters were assessed and 39 standardized radiographs (in triplicate) were taken before and 6 and 24 months after surgery. Using a computer-assisted analysis, the depth, width, and angle of the bony defects were measured. RESULTS: Statistically significant vertical clinical attachment gains (CAL-V: 3.15 +/- 1.63 mm to 3.31 +/- 1.65 mm; P<0.001) and bony fill (1.30 +/- 2.53 mm; P<0.01 to 1.54 +/- 2.70 mm; P<0.005) were observed 6 and 24 months postsurgically. In a multilevel regression analysis CAL-V gain was predicted by baseline CAL-V (P <0.0001), actual smoking (P <0.05), and age (P <0.1). Bony fill could be predicted by baseline height of the infrabony component (P<0.0001), gingival index at baseline (P<0.05), and actual smoking (P <0.01). In narrow (<26 degrees) and deep (> or = 3 mm) infrabony defects bony fill was more pronounced than in wide and shallow defects (P <0.05). CONCLUSIONS: Improvement achieved by guided tissue regeneration in infrabony defects can be maintained up to 24 months after surgery. Narrow and deep infrabony defects respond radiographically and to some extent clinically more favorably to GTR therapy than wide and shallow defects. However, depth of the infrabony component was a stronger prognostic parameter than defect angle. Actual smoking impairs the results of GTR therapy in infrabony defects.

Adult↗

Local 5-aminolevulinic acid application for laser light-induced fluorescence diagnosis of early staged colon cancer in rats.

BACKGROUND AND OBJECTIVES: 5-Aminolevulinic acid (ALA) increases the intracellular accumulation of endogenous protoporphyrin IX in colon cancer. Protoporphyrin IX itself is a potential photosensitizer that can be used for laser light-induced fluorescence diagnosis. The aim of this study was to detect cancer in the rat colon before macroscopic visibility. STUDY DESIGN/MATERIALS AND METHODS: Multifocal colon carcinomas were induced by weekly subcutaneous injections of 1,2-dimethylhydrazin-dihydrochloride in male Wistar rats. Local photosensitization was performed with an ALA colon lavage. Red fluorescence (635 nm) was induced by green laser-light irradiation with an Ar-Dye Laser (514 nm) in the colon. Fluorescence was observed by the naked eye with a filter at < 515 nm to eliminate the excitation light. RESULTS: Twenty-five Wistar rats developed 99 macroscopically visible carcinomas and four macroscopically visible dysplasias. The following laser-light-induced fluorescence diagnosis procedure was able to detect 16 additional carcinomas and 41 additional dysplasias. CONCLUSIONS: Local ALA application induces a tumor-specific protoporphyrin IX accumulation in the rat colon and is an efficient method for fluorescence detection of invisible dysplasias and early colon cancer in the rat.

1,2-Dimethylhydrazine↗