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1.
Int Arch Occup Environ Health ; 91(2): 155-174, 2018 02.
Article in English | MEDLINE | ID: mdl-29027001

ABSTRACT

OBJECTIVE: An ecologic study on the level of districts was performed to evaluate the possible association between district type and risk of cancer in Bavaria, Southern Germany. METHODS: Cancer incidence data for the years 2003-2012 were obtained from the population-based cancer registry Bavaria according to sex and cancer site. Data on district type, socio-economic area deprivation, particulate matter exposure, tobacco consumption, and alcohol consumption were obtained from publicly available sources. The possible association between district type and cancer risk adjusted for age, socio-economic area deprivation, particulate matter exposure, tobacco consumption, and alcohol consumption was evaluated using multivariable multi-level negative binomial regression. RESULTS: We found a significantly reduced cancer risk in densely populated districts close to core cities and/or rural districts compared to core cities with respect to the cancer sites mouth and pharynx (women only), liver (both sexes), larynx (both sexes), lung (both sexes), melanoma of the skin (both sexes), mesothelioma (men only), connective and soft tissue (both sexes), corpus uteri, other urinary tract (men only), urinary bladder (both sexes), and non-Hodgkin lymphoma (both sexes). CONCLUSION: Our findings require further monitoring. Since the apparently increased cancer risk in core cities may be related to lifestyle factors, preventive measures against lifestyle-related cancer could be specifically targeted at populations in deprived core cities.


Subject(s)
Cities/statistics & numerical data , Neoplasms/epidemiology , Rural Population/statistics & numerical data , Urban Population/statistics & numerical data , Age Distribution , Aged , Alcohol Drinking/epidemiology , Environmental Exposure/statistics & numerical data , Female , Germany/epidemiology , Humans , Incidence , Life Style , Male , Middle Aged , Particulate Matter , Registries , Residence Characteristics , Risk Factors , Sex Distribution , Smoking/epidemiology , Socioeconomic Factors
2.
Article in German | MEDLINE | ID: mdl-29075813

ABSTRACT

Cancer registries collect data about the occurrence and temporal changes of the occurrence of all types of cancer. This information is an important basis for health administration as well as for the evaluation of possible cancer causes. Cancer clusters can be detected by analysis of registry data according to place or district of residence of diseased persons. Cancer registries frequently receive enquiries from concerned citizens asking for investigation of the causes of suspected cancer clusters. The management of suspected cancer clusters can be described as crisis management due to the mixing of medical, biological, political, and psychological factors. In this article, we present an overview of current guidelines and methods for handling suspected cancer clusters by cancer registries. Moreover, the numerical analysis of small-scale cancer registry data is illustrated using two examples from the Bavarian Cancer Registry.


Subject(s)
Cluster Analysis , Leukemia/epidemiology , Neoplasms/epidemiology , Registries/statistics & numerical data , Small-Area Analysis , Adult , Causality , Child , Correlation of Data , Germany , Guideline Adherence , Health Education , Humans , Leukemia/therapy , Neoplasms/therapy , Prevalence , Risk Assessment
3.
Article in German | MEDLINE | ID: mdl-24357177

ABSTRACT

BACKGROUND: The incidence of thyroid cancer (TC), a rare malignancy, has strongly risen in recent decades. Possible causes of this rise include increasing diagnostic activity, nuclear tests after World War II, and the Chernobyl disaster. AIM: This article presents the time trends of TC incidence between 2003 and 2008 in Germany according to histological tumor type and sex, and provides a description of TC incidence according to districts (Kreise) and sex in Germany. METHODS: Data on persons newly diagnosed with thyroid cancer (ICD-10 code, C73) between 2003 and 2008 were obtained from the Center of Cancer Registry Data at the Robert Koch Institute. Official population and mortality data were used. Age-specific and age-standardized incidence rates (ASIR) were calculated according to sex and tumor histology. RESULTS: Between 2003 and 2008, the ASIR of TC rose from 2.7 to 3.4 (men) and from 6.5 to 8.9 (women) per 100,000 per year. This rise can be almost completely attributed to the rising incidence of papillary TC. The steepest rise in frequency was observed in TNM-T1 tumors. A positive north-south gradient of TC incidence was found. DISCUSSION: The cause of the marked rise of TC incidence in recent decades is unknown. The positive north-south gradient of the TC incidence may possibly be attributed in part to long-standing differences of iodine intake between different German regions. CONCLUSION: An epidemiological study of the possible causes of the rising TC incidence and of the regional differences of TC incidence in Germany is recommended.


Subject(s)
Carcinoma/mortality , Registries , Thyroid Neoplasms/mortality , Adult , Age Distribution , Aged , Aged, 80 and over , Carcinoma, Papillary , Female , Germany/epidemiology , Humans , Incidence , Male , Middle Aged , Proportional Hazards Models , Risk Factors , Sex Distribution , Spatio-Temporal Analysis , Survival Rate , Thyroid Cancer, Papillary
4.
Int Arch Occup Environ Health ; 86(7): 767-76, 2013 Oct.
Article in English | MEDLINE | ID: mdl-22949009

ABSTRACT

OBJECTIVE: To evaluate the possible association between uranium (U) content in public drinking water on the one hand and the risk of cancer of the colorectum, lung, female breast, prostate, kidney, and urinary bladder, total cancer, and leukemia on the other hand in Bavaria, an ecologic study on the level of municipalities was performed. METHODS: Cancer incidence data for the years 2002-2008 were obtained from the population-based cancer registry Bavaria according to sex. Current U content data of public drinking water on the level of municipalities were obtained from a publicly available source. The possible association between drinking water U content and cancer risk adjusted for average socio-economic status was evaluated using Poisson regression. RESULTS: Drinking water U content was below 20 µg/L in 458 out of 461 included municipalities. We found a significantly increased risk of leukemia in men in the intermediate (U level, 1.00-4.99 µg/L; relative risk [RR], 1.14) and in the highest U exposure category (U level, ≥5 µg/L; RR, 1.28). Moreover, in women, a significantly elevated risk was identified with respect to kidney cancer in the highest exposure category (RR, 1.16) and with respect to lung cancer in the intermediate exposure category (RR, 1.12). CONCLUSION: The slightly increased risk of leukemia in men, kidney cancer in women, and lung cancer in women may require further investigation. If an increased cancer risk is confirmed, preventive measures (e.g., introduction of U filters in public water systems) may be considered.


Subject(s)
Drinking Water/chemistry , Neoplasms/epidemiology , Registries , Uranium/analysis , Urban Population/statistics & numerical data , Aged , Female , Germany/epidemiology , Humans , Incidence , Kidney Neoplasms/epidemiology , Leukemia/epidemiology , Lung Neoplasms/epidemiology , Male , Middle Aged , Sex Factors , Uranium/toxicity , Water Supply
5.
Int Arch Occup Environ Health ; 82(3): 357-63, 2009 Feb.
Article in English | MEDLINE | ID: mdl-18649084

ABSTRACT

OBJECTIVE: To analyse the association between occupational ultraviolet (UV) light exposure and skin cancer (basal cell carcinoma, BCC; squamous cell carcinoma, SCC; cutaneous malignant melanoma, CMM) based on data from the Bavarian population-based cancer registry. METHODS: The population-based cancer registry of Bavaria (Germany) provided data on incident cases of BCC, SCC, and CMM, respectively, during the period 2001 until 2005. Eleven Bavarian districts with complete skin cancer registration were included in this analysis based on 2,156,336 person years. Cases were assigned to "indoor", "mixed indoor/outdoor", and "outdoor" exposure categories according to their job title. We computed age-specific and age-adjusted incidence rates of BCC (n = 1,641), SCC (n = 499), and CMM (n = 454) by work type, and the relative risk (RR) of skin cancer occurrence for "outdoor" and "mixed indoor/outdoor" workers, respectively, compared to "indoor" workers. RESULTS: The risk of BCC was substantially elevated in male (RR, 2.9; 95% CI, 2.2-3.9) and female (RR, 2.7; 95% CI, 1.8-4.1) outdoor workers compared to male and female indoor workers, respectively. We also found an elevated risk of similar magnitude for SCC in male (RR, 2.5; 95% CI, 1.4-4.7) and female (RR, 3.6; 95% CI, 1.6-8.1) outdoor workers compared to male and female indoor workers, respectively. CMM risk was not significantly associated with outdoor work. CONCLUSION: Our study confirms previous reports on the increased risk of BCC and SCC in outdoor workers compared to indoor workers.


Subject(s)
Neoplasms, Radiation-Induced/epidemiology , Occupational Diseases/etiology , Occupational Exposure , Registries , Skin Neoplasms/etiology , Ultraviolet Rays/adverse effects , Adult , Aged , Aged, 80 and over , Carcinoma, Basal Cell/epidemiology , Carcinoma, Basal Cell/etiology , Carcinoma, Squamous Cell/epidemiology , Carcinoma, Squamous Cell/etiology , Female , Germany/epidemiology , Humans , Incidence , Male , Melanoma/epidemiology , Melanoma/etiology , Middle Aged , Occupational Diseases/epidemiology , Occupations , Risk Factors , Skin Neoplasms/epidemiology , Young Adult
6.
Methods Inf Med ; 45(5): 548-56, 2006.
Article in English | MEDLINE | ID: mdl-17019510

ABSTRACT

OBJECTIVES: To evaluate split selection instability in six survival tree algorithms and its relationship with predictive error by means of a bootstrap study. METHODS: We study the following algorithms: logrank statistic with multivariate p-value adjustment without pruning (LR), Kaplan-Meier distance of survival curves (KM), martingale residuals (MR), Poisson regression for censored data (PR), within-node impurity (WI), and exponential log-likelihood loss (XL). With the exception of LR, initial trees are pruned by using split-complexity, and final trees are selected by means of cross-validation. We employ a real dataset from a clinical study of patients with gallbladder stones. The predictive error is evaluated using the integrated Brier score for censored data. The relationship between split selection instability and predictive error is evaluated by means of box-percentile plots, covariate and cutpoint selection entropy, and cutpoint selection coefficients of variation, respectively, in the root node. RESULTS: We found a positive association between covariate selection instability and predictive error in the root node. LR yields the lowest predictive error, while KM and MR yield the highest predictive error. CONCLUSIONS: The predictive error of survival trees is related to split selection instability. Based on the low predictive error of LR, we recommend the use of this algorithm for the construction of survival trees. Unpruned survival trees with multivariate p-value adjustment can perform equally well compared to pruned trees. The analysis of split selection instability can be used to communicate the results of tree-based analyses to clinicians and to support the application of survival trees.


Subject(s)
Models, Statistical , Survival Analysis , Algorithms , Cholecystolithiasis , Germany , Humans , Prospective Studies
7.
J Intern Med ; 255(6): 653-63, 2004 Jun.
Article in English | MEDLINE | ID: mdl-15147529

ABSTRACT

BACKGROUND: Recent studies show that nearly half of the hospitalized patients are readmitted within 6 months from discharge. No data exist about the relationship between adverse drug reactions (ADRs) and readmittance to a department of internal medicine. OBJECTIVES: The primary aims of the study were to determine if ADRs could be used as predictors for recurrent hospitalizations in internal medicine and to evaluate the economic impact of ADRs on hospitalization costs. DESIGN AND SETTING: A cohort-based, prospective, 18-month pharmacoepidemiological survey was conducted in the Department I of Internal Medicine at the University Hospital of Erlangen. All patients were intensively monitored for ADRs by a pharmacoepidemiological team. ADRs were evaluated for their offending drugs, probability, severity, preventability and classified by WHO-ART. During a 6-month period ADR-positive patients were matched to non-ADR patients applying diagnosis-related group categorization in order to measure the impact of ADRs on the duration and frequency of hospitalization. RESULTS: Of 1000 admissions 424 patients had single admissions and 206 patients had recurrent readmissions (min 1, max 9). The prevalence of readmissions was 37% (n = 370). In 145 (23%) of 630 patients, 305 ADRs were observed. The ADR incidence was similar in first admissions and readmissions. ADRs were not found to predict further readmissions and lack of ADRs did not preclude readmissions. ADRs caused hospitalizations in 6.2% of first admissions and in 4.2% of readmissions. According to the Schumock algorithm 135 (44.3%) ADRs were found to be preventable. The occurrence and numbers of ADRs per admission were found to prolong hospitalization period significantly (r = 0.48 and 0.51, P < 0.001, n = 135). Of 9107 treatment days 20% were caused by in-house (1130 days) and community-acquired ADRs (669 days). In admissions and readmissions 11% (>973 days) of all treatment days were judged to be preventable. CONCLUSIONS: Intensified drug monitoring supported by information technology in internal medicine is essential for early detecting and prevention of ADRs and saving hospital resources.


Subject(s)
Drug-Related Side Effects and Adverse Reactions , Patient Readmission/economics , Adolescent , Adult , Aged , Aged, 80 and over , Anti-Infective Agents/adverse effects , Cardiovascular Agents/adverse effects , Central Nervous System Agents/adverse effects , Drug Therapy/economics , Electrolytes/adverse effects , Gastrointestinal Agents/adverse effects , Hormones/adverse effects , Humans , Length of Stay , Middle Aged , Prospective Studies , Time Factors
8.
Methods Inf Med ; 43(5): 493-8, 2004.
Article in English | MEDLINE | ID: mdl-15702208

ABSTRACT

OBJECTIVES: Cancer epidemiologists are often asked by members of the interested public about possible associations between suspected carcinogens and apparently increased small-area cancer incidence rates. Frequently, no systematic incidence differences can be demonstrated. Nevertheless, it is necessary to address public concerns about suspected cancer clusters. To facilitate explanations about the large random variation of small-area tumor incidence, we implemented a software simulation tool in R. METHODS: Under the assumption of no cancer causes other than chance, the tool simulates a small village population with an average number of five inhabitants per house and allows graphical visualisation of ten streets with 100 houses. Published age-specific incidence and mortality data are used for event sampling based on the binomial distribution. Program parameters include sample size, age distribution, cancer incidence, and mortality rates. RESULTS: On average, 22 percent (2.2/10) of all houses per street have been inhabited by at least one cancer patient during the last five years in our simulated small village. A situation where all (10) houses in a street have been inhabited by at least one cancer patient during the last five years appears to be very rare (less than one in a million streets). CONCLUSIONS: Our software tool can be used effectively for numerical and graphical visualisation of small-area tumour incidence and prevalence rates due to chance alone. The explanation of basic epidemiological concepts to members of the public can help to increase public motivation and support for population-based cancer registration. Our simulation tool can be used to support this goal.


Subject(s)
Computer Simulation , Neoplasms/epidemiology , Small-Area Analysis , Adolescent , Adult , Aged , Aged, 80 and over , Child , Child, Preschool , Female , Germany/epidemiology , Humans , Incidence , Infant , Infant, Newborn , Male , Middle Aged , Neoplasms/mortality
10.
Artif Intell Med ; 28(3): 323-41, 2003 Jul.
Article in English | MEDLINE | ID: mdl-12927339

ABSTRACT

Tree-based methods can be used to generate rules for prognostic classification of patients that are expressed as logical combinations of covariate values. Several splitting algorithms have been proposed for generating trees from survival data. However, the choice of an appropriate algorithm is difficult and may also depend on clinical considerations. By means of a prognostic study of patients with gallbladder stones and of a simulation study, we compare the following splitting algorithms: log-rank statistic adjusted for measurement scale with (AP) and without (AU) pruning, exponential log-likelihood loss (EP), Kaplan-Meier (KP) distance of survival curves, unadjusted log-rank statistic (LP), martingale residuals (MP), and node impurity (ZP). With the exception of the AU algorithm (based on a Bonferroni-adjusted p-value driven stopping rule), trees are pruned using the measure of split-complexity, and optimally-sized trees are selected using cross-validation. The integrated Brier score is used for the evaluation of predictive models. According to the results of our simulation study and of the clinical example, we conclude that the AU, AP, EP, and LP algorithm may yield superior predictive accuracy. The choice among these four algorithms may be based on the required parsimonity and on medical considerations.


Subject(s)
Algorithms , Models, Statistical , Survival Analysis , Female , Gallstones/mortality , Humans , Male , Middle Aged , Proportional Hazards Models , Reproducibility of Results
11.
Anaesth Intensive Care ; 30(6): 763-5, 2002 Dec.
Article in English | MEDLINE | ID: mdl-12500514

ABSTRACT

Several tests have been proposed to predict difficult laryngoscopy or intubation. The thyromental distance (TMD) is often used for these purposes but this measurement, used alone, is unreliable. This study tested the hypothesis that the ratio of the patient's height to TMD (ratio of height to TMD = RHTMD) would improve the accuracy of predicting difficult laryngoscopy compared with TMD alone. Two hundred and seventy patients were evaluated preoperatively using the TMD and RHTMD. The two tests were compared analyzing the area under the receiver operating characteristic curves (AUC). Difficult laryngoscopy occurred in 16 patients (5.9%). The AUC of RHTMD was significantly greater (P < 0.007) when compared to TMD, indicating a more accurate prediction by the RHTMD. A ratio of 25 for the RHTMD was found to be the optimal cut-off value to predict difficult laryngoscopy. When the sensitivity of both tests was 0.81, the RHTMD had a significantly greater specificity (0.91) than the TMD (0.73). Based on our results, we recommend that the RHTMD should be used instead of the TMD.


Subject(s)
Body Height , Chin/anatomy & histology , Intubation, Intratracheal , Laryngoscopy , Thyroid Cartilage/anatomy & histology , Adolescent , Adult , Aged , Aged, 80 and over , Anthropometry , Female , Humans , Male , Middle Aged , Predictive Value of Tests , ROC Curve , Sensitivity and Specificity
12.
J Intern Med ; 252(4): 352-60, 2002 Oct.
Article in English | MEDLINE | ID: mdl-12366608

ABSTRACT

OBJECTIVES: Insulin-treated patients with diabetes are at a higher risk than the general population in causing traffic accidents due to hypoglycaemias. Preceding investigations focused on insulin-treated patients and hypoglycaemia-induced accidents as "end-points". We studied the incidence of symptomatic hypoglycaemia and hypoglycaemia-induced accidents during driving and put it in relation to the different treatment modes of insulin therapy (Conventional Insulin Treatment = CT, Intensified Conventional Insulin Treatment = ICT, Continuous Subcutaneous Insulin Infusion = CSII) as well as to patients treated with oral hypoglycaemia-inducing agents and the two main types of diabetes mellitus. SUBJECTS AND SETTING: We investigated 450 patients (122 treated with sulphonylureas, 151 with CT, 143 with ICT and 34 with CSII) by an anonymous questionnaire at different locations to avoid bias. A total of 176 persons had type 1 diabetes, 243 persons had type 2 diabetes, 31 subjects could not be classified. RESULTS: Symptomatic hypoglycaemias during driving were rare events with an occurrence of 0.19-8.26 (minimal and maximal mean, depending on the mode of treatment), if given as hypoglycaemias per 100 000 km on one treatment regimen, or 0.02-0.63, if given as events per year driven. Their incidence increased significantly with the degree of "strictness" between the treatment groups, except between the patients treated with ICT and CSII. Hypoglycaemia-induced accidents are rare with 0.01-0.49, if given as events per 100 000 km and 0.007-0.01, if given as events per year driven. These differences were not significant. Significant confounders influencing the traffic safety of the patients were age, duration of diabetes and concomitant antihypertensive medication. Analysing the data in accordance with the type of diabetes revealed a significantly higher rate of hypoglycaemic events in patients with type 1 diabetes. The number of hypoglycaemia-induced accidents was considerably higher in this group, but failed slightly to reach statistical significance. CONCLUSIONS: Hypoglycaemias during driving are rare events, their occurrence is significantly influenced by the treatment regimen and type of diabetes. Hypoglycaemia-induced accidents are extremely rare, presumably as a positive effect of patient education in our group.


Subject(s)
Accidents, Traffic , Diabetes Complications , Diabetes Mellitus/drug therapy , Hypoglycemia , Adult , Age Factors , Aged , Aged, 80 and over , Antihypertensive Agents/therapeutic use , Data Interpretation, Statistical , Diabetes Mellitus, Type 1/complications , Diabetes Mellitus, Type 1/drug therapy , Diabetes Mellitus, Type 2/complications , Diabetes Mellitus, Type 2/drug therapy , Female , Humans , Hypertension/complications , Hypertension/drug therapy , Hypoglycemia/etiology , Hypoglycemic Agents/administration & dosage , Hypoglycemic Agents/therapeutic use , Insulin/administration & dosage , Insulin/therapeutic use , Male , Middle Aged , Research Design
13.
Endoscopy ; 34(9): 703-10, 2002 Sep.
Article in English | MEDLINE | ID: mdl-12195327

ABSTRACT

BACKGROUND AND STUDY AIMS: Real-time digital video transmission (rtDVT) at an acceptable quality through networks has been possible for several years. This technique can be used for telemedical applications, such as tele-endoscopy. The hypotheses of the present study were that the quality of real-time DVT depends on the technical equipment used, and that the resulting image quality influences the usability of the system for diagnostic purposes. MATERIALS AND METHODS: An experimental network was established between two German referral endoscopy centers, using the Asynchronous Transfer Mode (ATM) protocol. At first, rtDVTs of routine gastrointestinal video endoscopies were transferred through the network for prospective evaluation of the feasibility of the technical equipment and its usability for diagnostic tele-endoscopy, based on the video image quality. Secondly, the image quality and usability for correct telemedical diagnosis were evaluated prospectively in a double-blind experimental setting in relation to variations in the methods of data compression used, transmission bandwidths, and simulated transmission errors. Fourteen endoscopists evaluated 27 variations of an endoscopic video sequence. RESULTS: Compression with the Moving Picture Expert Group 2 (MPEG2 [4 : 2 : 2]) standard, the ATM protocol, and a bandwidth of 40 megabits per second (Mb/s) were used successfully in 40 routine tele-endoscopies for practical evaluation. Doctors were able to handle the system with ease, and its availability was 100%. There were no detectable differences between the original video image and the transferred image, and the images were usable for diagnosis in all cases. The set-up used clinically was therefore considered to provide the optimal conditions for comparisons in the experimental part of the study. Experimentally, any technical variation was found to cause a reduction in the overall image quality and hence a reduction in diagnostic usability: compression algorithm (MPEG2 [4 : 2 : 2] vs. others: P = 0.001), bandwidth (> or = 8 vs. < 8 Mb/s: P = 0.001), and error rate (10 (-8) vs. 10 (-7): P = 0.001). CONCLUSIONS: rtDVT using MPEG2 [4 : 2 : 2] compression and a bandwidth of 40 Mb/s did not effectively differ from the original video images in routine tele-endoscopy. The qualitative requirements in diagnostic video endoscopy, however, are obviously much higher than previously assumed, since experienced endoscopists detected a loss of image quality and a reduction in diagnostic usability with any reduction in the technical specification. Modern methods of data compression, broadband networks and a network protocol with good quality-of-service guarantees are therefore prerequisites for diagnostic rtDVT.


Subject(s)
Endoscopy, Gastrointestinal , Image Processing, Computer-Assisted , Telemedicine , Algorithms , User-Computer Interface , Video Recording
14.
Int J Colorectal Dis ; 17(2): 115-22, 2002 Mar.
Article in English | MEDLINE | ID: mdl-12014419

ABSTRACT

BACKGROUND AND AIMS: We analyzed bone and mineral metabolism after long-segment small bowel resection in the rat to detect functional and morphological alterations and to determine the development of osteopathy. METHODS: Twelve-week-old male Lewis rats were randomized into short (8-week) or long (16-week) follow-up groups. Sham operation, resection of the proximal third of the small bowel, resection of the distal third of the bowel and resection of the entire jejunum and ileum were carried out. Nineteen days before the end of the experiment the animals were transferred into a metabolic cage to analyze weight gain/loss, food intake, and fecal excretion/24 h. At the end of the experiment the animals were killed; blood samples and bowel and bone specimens were collected, length, weight, volume, density, mineral content, and fracturing energy were determined, and bone histology was examined. The calcium/phosphorus ratio, nonmineralized tissue content and the ratio fracturing energy/mean bone density were calculated. RESULTS: After 8 weeks there were significant differences to the control group in body weight, weight gain, food efficiency, femur length, weight, volume, mineral content, mineral density, fracturing energy per bone volume, and bone density but not in bone calcium or magnesium. After 16 weeks there were differences in body weight, weight gain, food efficiency, femur length, weight, volume, bone mineral content and density, bone minerals, and nonmineralized tissue but not in fracturing energy; the average values of all these parameters were lower in the resected groups, and lowest in the group after resection of the entire jejunum and ileum. Bone histology showed a reduction in trabecular bone mass after long-segment small bowel resection. CONCLUSIONS: Long-segment small bowel resection causes a significant loss of body weight despite of a comparable mean chow ingestion resulting in a significant decreased food efficiency. We conclude that there is no inverse relationship of bone calcium content and the fracture risk, and that there is no severe mineralization defect after long-segment small bowel resection.


Subject(s)
Bone Density , Bone and Bones/metabolism , Intestine, Small/surgery , Animals , Biomechanical Phenomena , Bone Diseases, Metabolic/etiology , Bone Diseases, Metabolic/metabolism , Bone Diseases, Metabolic/physiopathology , Bone and Bones/pathology , Bone and Bones/physiopathology , Calcium/metabolism , Femur/metabolism , Femur/pathology , Femur/physiopathology , Magnesium/metabolism , Male , Phosphorus/metabolism , Rats , Rats, Inbred Lew
15.
Br J Oral Maxillofac Surg ; 40(1): 37-44, 2002 Feb.
Article in English | MEDLINE | ID: mdl-11883968

ABSTRACT

Inflammatory lesions of the vascular endothelium after preoperative radiotherapy often cause healing-delayed healing of free flaps in the irradiated graft bed. We investigated changes in neovascularization in the transition area between grafted tissues and irradiated tissues of the graft bed. We irradiated the neck(30 and 50 Gy total dose) in 102 Wistar rats and then grafted a free myocutaneous gracilis flap to the irradiated region of the neck 4 weeks later. We examined histologically the tissues of the graft, the transition area between the graft and the irradiated graft bed, and the graft bed. In contrast to control rats, the tissues in the irradiated animals showed a qualitatively reduced and a more irregular capillary distribution, with substantial fibrosis in the irradiated graft bed. We also found significant differences in vascularization and mean capillary lumen in the transitional zone between graft and graft bed in the irradiated rats compared with controls (P = 0.004 and P < 0.001, respectively). Both number and diameter of capillaries were reduced in the irradiated graft bed tissue. The graft failed to improve vascularization in the transitional zone between graft and irradiated tissue, so we conclude that it is the vascularization status of the bed tissue rather than that of the transplant tissue that is the limiting factor for graft healing.


Subject(s)
Cranial Irradiation/adverse effects , Endothelium, Vascular/radiation effects , Neovascularization, Physiologic/radiation effects , Surgical Flaps/blood supply , Animals , Graft Survival/radiation effects , Immunohistochemistry , Male , Muscle, Skeletal/blood supply , Muscle, Skeletal/transplantation , Neck/surgery , Rats , Rats, Wistar , Skin Transplantation/physiology , Statistics, Nonparametric
16.
Brain ; 124(Pt 12): 2372-82, 2001 Dec.
Article in English | MEDLINE | ID: mdl-11701592

ABSTRACT

We studied the post-ganglionic cardiac sympathetic innervation in patients with chronic temporal lobe epilepsy (TLE) by means of [(123)I]metaiodobenzylguanidine-single photon computed tomography (MIBG-SPECT) and evaluated the effects of carbamazepine on cardiac sympathetic innervation. TLE is frequently associated with dysfunction of the autonomic nervous system. Autonomic dysregulation might contribute to unexplained sudden death in epilepsy. Anticonvulsive medication, particularly with carbamazepine, might also influence autonomic cardiovascular modulation. MIBG-SPECT allows the quantification of post-ganglionic cardiac sympathetic innervation, whereas measuring the variability of the heart rate provides only functional parameters of autonomic modulation. Antiepileptic drugs, especially carbamazepine (CBZ), can affect cardiovascular modulation. We determined the index of cardiac MIBG uptake (heart/mediastinum ratio) and heart rate variability (HRV) using time and frequency domain parameters of sympathetic and parasympathetic modulation in 12 women and 10 men (median age 34.5 years) with a history of TLE for 7-41 years (median 20 years). Myocardial perfusion scintigrams were examined to rule out deficiencies of MIBG uptake due to myocardial ischaemia. To assess the possible effects of CBZ on autonomic function, we compared MIBG uptake and HRV in 11 patients who had taken CBZ and 11 patients who had not taken CBZ, and in 16 healthy controls. In order to identify MIBG uptake defects due to myocardial ischaemia, all patients had a perfusion scintigram. Cardiac MIBG uptake was significantly less in the TLE patients (1.75) than in the controls (2.14; P = 0.001), but did not differ between subgroups with and without CBZ treatment. The perfusion scintigram was normal in all patients. Time domain analysis of HRV parameters suggested the predominance of parasympathetic cardiac activity in the TLE patients, but less parasympathetic modulation in the patients treated with CBZ than in those not treated with CBZ (P < 0.05), whereas frequency domain parameters showed no significant difference between the subgroups of patients or between patients and controls. MIBG-SPECT demonstrates altered post-ganglionic cardiac sympathetic innervation. This dysfunction might carry an increased risk of cardiac abnormalities.


Subject(s)
Autonomic Nervous System/physiopathology , Epilepsy, Temporal Lobe/diagnostic imaging , Epilepsy, Temporal Lobe/physiopathology , Heart/diagnostic imaging , Tomography, Emission-Computed, Single-Photon , 3-Iodobenzylguanidine , Adult , Autonomic Nervous System/cytology , Coronary Circulation , Death, Sudden/etiology , Epilepsy, Temporal Lobe/complications , Female , Heart/innervation , Heart Rate , Humans , Iodine Radioisotopes , Male , Middle Aged , Radiopharmaceuticals , Sympathetic Fibers, Postganglionic/physiopathology
17.
Clin Oral Implants Res ; 12(5): 495-502, 2001 Oct.
Article in English | MEDLINE | ID: mdl-11564110

ABSTRACT

In a prospective study, 20 patients who underwent harvesting of chin grafts as outpatients, were followed up for 12 months (3 further patients with incomplete follow-up data were excluded from the study). Preoperatively and 7 days, 1, 3, 6 and 12 months postoperatively, follow-up data were assessed. Evaluation of the superficial sensory function of the inferior alveolar nerve was determined by the Pointed-Blunt Test and the Two-Point-Discrimination Test. Sensory disturbances were objectively assessed by testing thermal sensitivity with the "Pain and Thermal Sensitivity" Test (PATH Test). In addition, evaluation of the pulp sensitivity of teeth 35-45 was carried out by cold vitality testing. One week postoperatively, 8 patients were affected by superficial sensory impairment. 8 nerve territories showed hypoaesthetic reactions and 5 showed hyperaesthetic reactions. After 12 months, two patients still suffered from hypoaesthesia of one side of the chin. There was a statistically significant sensitivity impairment of the chin for all patients comparing the preoperative data of the Two-Point-Discrimination Test (left/right median: 8.17/8.17 mm, interquartile range (IQR) 1.00/2.00 mm) with the first postoperative measurement (left/right median 9.00/8.33 mm, IQR 1.67/2.66 mm). Comparing the latter to the last postoperative measurement there was significant tendency for regeneration of a nerve function (left/right median 8.00/7.84 mm, IQR 0.66/2.00 mm). In the PATH Test all hypoaesthetic areas could be identified by a reduction of thermal sensitivity. After the first postoperative examination 21.6% (n=38/176) of the examined teeth had lost their pulp sensitivity. After 12 postoperative months 11.4% (n=20/176) still did not react sensitively. Many of these were canines (n=8/20). Comparing the preoperative to the first postoperative examination, there was a significant reduction of pulp sensitivity. However, statistically significant recovery until the last postoperative follow-up could not be detected. The assessed data show that patients have to be informed extensively about disturbances of the inferior alveolar nerve function lasting longer than 12 months. Moreover, the loss of pulp sensitivity is a very frequent event which has always to be taken into account. Considering the high rate of complications with harvesting of chin grafts, more prospective trials should be done to find out whether there are other donor sites for autogenous bone which put less strain on patients.


Subject(s)
Bone Transplantation , Chin , Tissue and Organ Harvesting/adverse effects , Ambulatory Surgical Procedures , Chin/innervation , Cold Temperature , Cuspid/innervation , Dental Pulp/innervation , Follow-Up Studies , Humans , Hyperesthesia/etiology , Hypesthesia/etiology , Mandibular Nerve/physiopathology , Nerve Regeneration/physiology , Pain, Postoperative/etiology , Prospective Studies , Recovery of Function/physiology , Sensation/physiology , Statistics as Topic , Statistics, Nonparametric , Temperature , Touch/physiology , Transplantation, Autologous
18.
Auton Neurosci ; 89(1-2): 31-7, 2001 Jun 20.
Article in English | MEDLINE | ID: mdl-11474644

ABSTRACT

Myenteric neurons were investigated morphometrically to answer the question if type-specific somal hypertrophy of type VI neurons in mechanically stressed ileum of pigs, which was known from an earlier study, is correlated with an increased dendritic arborization, that is, with dendritic hypertrophy. Muscular hypertrophy was induced in the ileum of two juvenile pigs by narrowing the gut circumference (mechanical stenosis) and by reversing a loop of ileum which results in an antiperistaltic segment (functional stenosis), respectively. After a survival time of 6 weeks, wholemounts from the pre- and poststenotic ileal regions, from the antiperistaltic segment as well as from an age matched control animal, were silver impregnated. Dendritic parameters of Stach types IV and VI neurons were recorded using a computer-aided morphometric program and analysed statistically. Type IV neurons showed no change of dendritic parameters, neither within control nor within stenosed ileal segments. In contrast, the type VI neurons displayed increased dendritic parameters within zones of muscular hypertrophy such as total dendritic length, numbers of dendrites, of dendritic branching points and of dendritic endings. We suggest that type VI neurons may participate as descending nitrergic interneurons or motorneurons in the control of muscular function, thus, undergoing plastic changes in case of experimental muscular hypertrophy. Type IV neurons which are involved in the regulation of mucosal processes were not affected by muscular hypertrophy.


Subject(s)
Dendrites/physiology , Ileum/innervation , Myenteric Plexus/cytology , Neurons/ultrastructure , Animals , Cell Size/physiology , Hypertrophy , Ileum/pathology , Ileum/surgery , Male , Muscle, Smooth/innervation , Muscle, Smooth/pathology , Muscle, Smooth/surgery , Neurons/physiology , Peristalsis , Stress, Mechanical , Swine
19.
Biomed Tech (Berl) ; 46(5): 124-8, 2001 May.
Article in German | MEDLINE | ID: mdl-11413908

ABSTRACT

External pneumatic compression of the foot is being used more and more to increase the venous blood flow in the lower limbs and thus reduce the risk of postoperative deep venous thrombosis. We have investigated the efficacy of the foot pump pneumatic compression device (A-V Impulse, Novamedix, Andover, England) in 10 healthy subjects and in 10 patients undergoing total hip arthroplasty. The velocity of venous blood flow in the common femoral artery was measured in the horizontal, Trendelenburg (head-down, foot-up) and reverse Trendelenburg (head-up and foot-down) positions using a duplex ultrasound unit (Sonoline Elegra, Siemens, Erlangen, Germany) with a 5 MHz linear array probe. Application of the foot pump produced an increase in venous blood flow velocity in all healthy subjects and in all patients. In healthy subjects the mean increase in the horizontal position was 31.18% (SD = 15.86%), and in the Trendelenburg position 20.72 (SD = 15.69%) (right limb). In the reverse Trendelenburg position, the foot pump produced a mean increase of 94.08% (SD = 55.00%). The difference is statistically significant (p < 0.005). In patients with a total hip arthroplasty, the mean increase in the horizontal position was 28.67% (SD = 9.95%), and in the Trendelenburg position 20.34% (SD = 17.85%) (operated limb). In the reverse Trendelenburg, the foot pump produced a mean increase of 91.55% (SD = 42.38%). The difference is statistically significant (p < 0.005). There was no noteworthy difference in results between the controls and patients. Pneumatic compression devices designed to reduce venous stasis are effective in decreasing the rate of deep venous thrombosis after surgery on the lower limb. The results of the present study show that the efficiency of the foot pump in increasing venous return is improved by adopting the reverse Trendelenburg position. This may increase its thromboprophylactic effect.


Subject(s)
Arthroplasty, Replacement, Hip , Bandages , Foot/blood supply , Leg/blood supply , Postoperative Complications/physiopathology , Posture/physiology , Venous Pressure/physiology , Venous Thrombosis/physiopathology , Adult , Aged , Blood Flow Velocity/physiology , Equipment Design , Female , Humans , Male , Middle Aged , Postoperative Complications/prevention & control , Venous Thrombosis/prevention & control
20.
Intensive Care Med ; 27(4): 686-93, 2001 Apr.
Article in English | MEDLINE | ID: mdl-11398694

ABSTRACT

OBJECTIVE: First, to evaluate the role of typical intensive care-related conditions like sepsis, prolonged ventilation, drug effects and metabolic disorders in the pathogenesis of critical illness polyneuropathy (CIP); second, to investigate the possible significance of patient serum neurotoxicity assessed by an in vitro cytotoxicity assay with respect to CIP development. DESIGN: Prospective study. SETTING: Neurological intensive care unit. PATIENTS AND PARTICIPANTS: Twenty-eight patients who were on mechanical respiratory support for at least 4 days during a 21-month study period. RESULTS: Diagnosis of CIP was established by clinical and electrophysiological examination in 16 (57%) of 28 patients. Patients were investigated on days 4, 8 and 14 of mechanical ventilation. Two of 16 CIP patients had clinical signs of polyneuropathy at initial examination. Factors that correlated significantly with the development of CIP were: the multiple organ failure score on day 8 of ventilation, the total duration of respiratory support, the presence of weaning problems and the manifestation of complicating sepsis and/or lung failure. The in vitro toxicity assay showed serum neurotoxicity in 12 of 16 CIP patients. Electrophysiological investigations yielded false positive results of the toxicity assay in six patients (not developing CIP) and false negative results in four patients (developing clinical and electrophysiological signs of CIP). Statistical analysis did not reveal a significant correlation between the diagnosis of CIP and the finding serum neurotoxicity. CONCLUSION: The results support the hypothesis of a multi-factorial aetiopathogenesis of CIP. We observed serum neurotoxicity in the majority of CIP patients, indicating the possible involvement of a so far unknown, low-molecular-weight neurotoxic agent in CIP pathogenesis.


Subject(s)
Neurotoxicity Syndromes/pathology , Neurotoxicity Syndromes/physiopathology , Polyneuropathies/pathology , Polyneuropathies/physiopathology , Adrenal Cortex Hormones/adverse effects , Aged , Aminoglycosides , Anti-Bacterial Agents/adverse effects , Biological Assay , Cell Culture Techniques , Electromyography , Female , Humans , Intensive Care Units , Male , Metabolic Diseases/complications , Middle Aged , Neuromuscular Blocking Agents/adverse effects , Neurotoxicity Syndromes/complications , Polyneuropathies/etiology , Prospective Studies , Respiration, Artificial/adverse effects , Sepsis/complications
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