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1.
Fortschr Neurol Psychiatr ; 83(10): 555-62, 2015 Oct.
Article in German | MEDLINE | ID: mdl-26588718

ABSTRACT

OBJECTIVE: To draft a clinical profile of mentally ill first-generation Spanish immigrants in Germany treated in a special setting in their native language and to identify possible correlations between time of onset of a mental disorder and migration and also between degree of utilization and clinical as well as care variables. METHOD: Statistical reanalysis of individual data (n = 100) of a previously published descriptive study with aggregated data corresponding to 15 variables. Correlations are calculated using chi-square as well as Fisher's exact test. Multivariate regression and logistic models were conducted. In addition to the explained variance of the models (R(2)), analyses of residuals as well as post-hoc power analyses (1-ß) were performed. RESULTS: A quarter of the sample (26 %) was mentally ill before migration; most of the patients received treatment very late (about 10 years after onset) and became chronically ill. Half of the sample shows a relevant somatic comorbidity and large average lengths of inpatient stays (54 days). In 16 % of treated cases, repatriation had to be organized. The degree of chronicity correlates with mental illness prior to migration. Severe mood disorders and psychoses occur late after having migrated, addictions and neurotic disorders are equally distributed over time. DISCUSSION: Migration can not be set in a causal relationship with the development of mental disorders, although there is a positive correlation between affective disorders and the duration of the migration status. Chronicity is related to an outbreak of the disease before migration. The sample is relatively homogeneous (one nationality, first generation), but loses epidemiological representativeness (not related to a catchment area).


Subject(s)
Mental Disorders/epidemiology , Mental Disorders/psychology , Mentally Ill Persons/statistics & numerical data , Transients and Migrants/psychology , Transients and Migrants/statistics & numerical data , Adult , Chronic Disease , Comorbidity , Emigration and Immigration/statistics & numerical data , Female , Germany/epidemiology , Hospitalization , Humans , Length of Stay , Male , Mood Disorders/epidemiology , Mood Disorders/psychology , Psychotic Disorders/epidemiology , Psychotic Disorders/psychology , Retrospective Studies , Spain/ethnology
2.
Osteoporos Int ; 23(7): 1957-65, 2012 Jul.
Article in English | MEDLINE | ID: mdl-22086309

ABSTRACT

SUMMARY: Although the amount of bone explains the largest amount of variability in bone strength, there is still a significant proportion unaccounted for. The morphology of individual bone trabeculae explains a further proportion of the variability in bone strength and bone elements that contribute to bone strength depending on the direction of loading. INTRODUCTION: Micro-CT imaging enables measurement of bone microarchitecture and subsequently mechanical strength of the same sample. It is possible using micro-CT data to perform morphometric analysis on individual rod and plate bone trabeculae using a volumetric spatial decomposition algorithm and hence determine their contribution to bone strength. METHODS: Twelve pairs of vertebral bodies (T12/L1 or L4/L5) were harvested from human cadavers, and bone cubes (10 × 10 × 10 mm) were obtained. After micro-CT imaging, a volumetric spatial decomposition algorithm was applied, and measures of individual trabecular elements were obtained. Bone strength was measured in compression, where one bone specimen from each vertebral segment was tested supero-inferiorly (SI) and the paired specimen was tested antero-posteriorly (AP). RESULTS: Bone volume fraction was the strongest individual determinant of SI strength (r(2) = 0.77, p < 0.0001) and AP (r(2) = 0.54, p < 0.0001). The determination of SI strength was improved to r(2) = 0.87 with the addition of mean rod length and relative plate bone volume fraction. The determination of AP strength was improved to r(2) = 0.85 with the addition of mean rod volume and relative rod bone volume fraction. CONCLUSIONS: Microarchitectural measures of individual trabeculae that contribute to bone strength have been identified. In addition to the contribution of BV/TV, trabecular rod morphology increased the determination of AP strength by 57%, whereas measures of trabecular plate and rod morphology increased determination of SI strength by 13%. Decomposing vertebral body bone architecture into its constituent morphological elements shows that trabecular element morphology has specific functional roles to assist in maintaining skeletal integrity.


Subject(s)
Bone Density/physiology , Lumbar Vertebrae/physiology , Thoracic Vertebrae/physiology , Aged , Aged, 80 and over , Algorithms , Anisotropy , Cadaver , Female , Humans , Imaging, Three-Dimensional/methods , Lumbar Vertebrae/anatomy & histology , Lumbar Vertebrae/diagnostic imaging , Male , Middle Aged , Stress, Mechanical , Thoracic Vertebrae/anatomy & histology , Thoracic Vertebrae/diagnostic imaging , X-Ray Microtomography
3.
Bone ; 39(6): 1182-9, 2006 Dec.
Article in English | MEDLINE | ID: mdl-16949356

ABSTRACT

Direct assessment of bone competence in vivo is not possible, hence, it is inevitable to predict it using appropriate simulation techniques. Although accurate estimates of bone competence can be obtained from micro-finite element models (muFE), it is at the expense of large computer efforts. In this study, we investigated the application of structural idealizations to represent individual trabeculae by single elements. The objective was to implement and validate this technique. We scanned 42 human vertebral bone samples (10 mm height, 8 mm diameter) with micro-computed tomography using a 20 microm resolution. After scanning, direct mechanical testing was performed. Topological classification and dilation-based algorithms were used to identify individual rods and plates. Two FE models were created for each specimen. In the first one, each rod-like trabecula was modeled with one thickness-matched beam; each plate-like trabecula was modeled with several beams. From a simulated compression test, assuming one isotropic tissue modulus for all elements, the apparent stiffness was calculated. After reducing the voxel size to 40 microm, a second FE model was created using a standard voxel conversion technique. Again, one tissue modulus was assumed for all elements in all models, and a compression test was simulated. Bone volume fraction ranged from 3.7% to 19.5%; Young's moduli from 43 MPa to 649 MPa. Both models predicted measured apparent moduli equally well (R2 = 0.85), and were in excellent agreement with each other (R2 = 0.97). Tissue modulus was estimated at 9.0 GPa and 10.7 GPa for the beam FE and voxel FE models, respectively. On average, the beam models were solved in 219 s, reducing CPU usage up to 1150-fold as compared to 40 microm voxel FE models. Relative to 20 microm voxel models 10,000-fold reductions can be expected. The presented beam FE model is an abstraction of the intricate real trabecular structure using simple cylindrical beam elements. Nevertheless, it enabled an accurate prediction of global mechanical properties of microstructural bone. The strong reduction in CPU time provides the means to increase throughput, to analyze multiple loading configuration and to increase sample size, without increasing computational costs. With upcoming in vivo high-resolution imaging systems, this model has the potential to become a standard for mechanical characterization of bone.


Subject(s)
Models, Anatomic , Models, Biological , Spine/anatomy & histology , Spine/physiology , Biomechanical Phenomena/methods , Biomechanical Phenomena/statistics & numerical data , Finite Element Analysis , Humans , Imaging, Three-Dimensional , In Vitro Techniques , Spine/diagnostic imaging , Tomography, X-Ray Computed
4.
Bone ; 39(2): 289-99, 2006 Aug.
Article in English | MEDLINE | ID: mdl-16540385

ABSTRACT

Synchrotron radiation micro-computed tomography (SRmicroCT) is a very useful technique when it comes to three-dimensional (3D) imaging of complex internal and external geometries. Being a fully non-destructive technique, SRmicroCT can be combined with other experiments in situ for functional imaging. We are especially interested in the combination of SRmicroCT with mechanical testing in order to gain new insights in the failure mechanism of trabecular bone. This interest is motivated by the immense costs in health care due to patients suffering from osteoporosis, a systemic skeletal disease resulting in decreased bone stability and increased fracture risk. To better investigate the different failure mechanisms on the microlevel, we have developed a novel in situ mechanical compression device, capable of exerting both static and dynamic displacements on experimental samples. The device was calibrated for mechanical testing using solid aluminum and bovine trabecular bone samples. To study different failure mechanisms in trabecular bone, we compared a fatigued and a non-fatigued bovine bone sample with respect to failure initiation and propagation. The fatigued sample failed in a burst-like fashion in contrast to the non-fatigued sample, which exhibited a distinct localized failure band. Moreover, microscopic cracks - microcracks and microfractures - were uncovered in a 3D fashion illustrating the failure process in great detail. The majority of these cracks were connected to a bone surface. The data also showed that the classification of microcracks and -fractures from 2D section can sometimes be ambiguous, which is also true for the distinction of diffuse and distinct microdamage. Detailed investigation of the failure mechanism in these samples illustrated that trabecular bone often fails in delamination, providing a mechanism for energy dissipation while conserving trabecular bone architecture. In the future, this will allow an even better understanding of bone mechanics related to its hierarchical structural organization.


Subject(s)
Bone and Bones/diagnostic imaging , Bone and Bones/physiopathology , Fractures, Stress/diagnostic imaging , Fractures, Stress/physiopathology , Imaging, Three-Dimensional , Light , Synchrotrons , Video Recording/methods , Animals , Cattle , Equipment Design/instrumentation , Equipment Design/methods , Stress, Mechanical , Tomography, X-Ray Computed
5.
J Orthop Res ; 24(5): 917-25, 2006 May.
Article in English | MEDLINE | ID: mdl-16583445

ABSTRACT

The goal of our study was to evaluate two newly developed implant designs and their behavior in terms of subsidence in lumbar vertebral bodies under cyclic loading. The new implants were evaluated in two different configurations (two small prototypes vs. one large prototype with similar load-bearing area) in comparison to a conventional screw-based implant (MACS TL). A pool of 13 spines with a total of 65 vertebrae was used to establish five testing groups of similar bone mineral density (BMD) distribution with eight lumbar vertebrae each. In additional to BMD assessment via dual-energy X-ray absorptiometry, cancellous BMD and structural parameters were determined using a new generation in vivo 3D-pQCT. The specimens were loaded sinusoidally in force control at 1 Hz for 1000 cycles at three load levels (100, 200, and 400 N). A survival analysis using the number of cycles until failure (Cox regression with covariates) was applied to reveal differences between implant groups. All new prototype configurations except the large cylinder survived significantly longer than the control group. The number of cycles until failure was significantly correlated with the structural parameter Tb.Sp. and similarly with the cancellous BMD for three of five implants. In both large prototypes the cycle number until failure significantly correlated with the preoperative distance to the upper endplates. Although the direct relationship between bone structure or density and mechanical breakage behavior cannot be conclusively proven, all the prototypes adapted for poor bone structure performed better than the comparable conventional implant.


Subject(s)
Lumbar Vertebrae/surgery , Osteoporosis/surgery , Prostheses and Implants , Aged , Aged, 80 and over , Biomechanical Phenomena , Bone Density , Bone Screws , Female , Humans , Male , Stress, Mechanical
6.
J Nucl Med ; 24(10): 937-44, 1983 Oct.
Article in English | MEDLINE | ID: mdl-6619964

ABSTRACT

Glutamate dehydrogenase (GDH), immobilized on CNBr-activated Sepharose supports, was used with N-13 ammonia to aminate alpha-ketoisocaproic acid (KIC), and alpha-ketoisovaleric acid (KIV) to produce N-13-labeled branched-chain L-amino acids with radiochemical yields ranging from 29% to 35%. From kinetic and practical considerations, pH 7.5-8.0 was established to be optimal for the synthesis of N-13-labeled branched-chain-L-amino acids. Myocardial time-activity curves in dogs at control, during low-flow ischemia, reperfusion, and after transaminase inhibition following intracoronary bolus injection of the N-13-labeled amino acids were biexponential. Higher retention of N-13 activity was observed in ischemic segments both during low-flow ischemia (29.2%) and reperfusion (23.2%) when compared with controls (20.0%), (n = 4). On the other hand, transaminase inhibition decreased residue fractions from 21.0% at control to 13.9% (n = 4). The residual activity with L-[1-11C]leucine allows for the calculation of protein synthesis rates.


Subject(s)
Amino Acids, Branched-Chain/biosynthesis , Carbon Radioisotopes/metabolism , Myocardium/metabolism , Nitrogen Radioisotopes/metabolism , Animals , Coronary Disease/metabolism , Dogs , Enzymes, Immobilized/metabolism , Glutamate Dehydrogenase/metabolism , Hydrogen-Ion Concentration , Kinetics , Leucine/biosynthesis , Transaminases/antagonists & inhibitors , Valine/biosynthesis
7.
J Endocrinol ; 80(3): 281-8, 1979 Mar.
Article in English | MEDLINE | ID: mdl-438706

ABSTRACT

The binding of oestradiol to a nuclear fraction extracted from human breast carcinomatous tissue was demonstrated. The material, which was extracted with KCl, sedimented at 3--4S and bound oestradiol with high affinity (dissociation constant approximately 2 X 10(-10) mol/l). Oestriol, diethylstilboestrol and 5 alpha-dihydrotestosterone (100-fold excesses) competed with [3H]oestradiol for the binding sites (binding inhibited by 89 +/- 8 (S.D.), 92 +/- 6 and 57 +/- 8% respectively), whereas progesterone and cortisol (100-fold excesses) did not (binding suppressed by 5 +/- 5 and 2 +/- 3% respectively). Similar competition patterns were found for cytoplasmic material which bound oestradiol. The binding occurred at 4 degrees C and was therefore considered to be a measure of the amount of binding material unoccupied by endogenous oestrogen, Unoccupied binding sites for oestradiol in the nucleus and cytoplasm were measured in 35 samples of breast carcinomatous tissue using sucrose gradient centrifugation. In 17 out of 35 tumorus, unoccupied nuclear and cytoplasmic 8S and 4S binding sites could be detected. Three out of 35 tumours contained unoccupied nuclear binding sites and 4S cytoplasmic binding sites. Nuclear binding sites only were found in two out of 35 tumours. Unoccupied nuclear binding sites were not detected in 13 out of 35 tumours and ten of these tumours also did not contain unoccupied cytoplasmic binding sites.


PIP: This study examines unoccupied binding sites for estradiol by using carcinomatous tissues of human breast. Estradiol, estriol, diethylstilbestrol and dihydrotestosterone demonstrated a higher affinity for binding sites, while progesterone and cortisol did not. Similar patterns were found for cytoplasmic material, and the binding occurred at 40C. In addition the quantities of unoccupied binding sites for estradiol in nuclei and in cytoplasm from 35 samples of human breast carcinomatous tissue were measured. Nuclear binding sites only were found in 2 out of 35 tumors, while unoccupied nuclear binding sites were not detected in 13 out of 35 tumors; 10 of these 13 did not contain unoccupied cytoplasmatic binding sites.


Subject(s)
Breast Neoplasms/metabolism , Breast/metabolism , Estradiol/metabolism , Receptors, Estrogen/metabolism , Adult , Aged , Binding, Competitive , Cell Nucleus/metabolism , Centrifugation, Density Gradient , Cytoplasm/metabolism , Female , Humans , Middle Aged , Potassium Chloride , Protein Binding , Receptors, Estrogen/drug effects , Trypsin/pharmacology
8.
Spine (Phila Pa 1976) ; 19(1): 57-61, 1994 Jan 01.
Article in English | MEDLINE | ID: mdl-8153805

ABSTRACT

This study was undertaken to evaluate the efficiency of intraosseous endoscopy for the insertion of pedicle screws. Adult sheep served as an animal model. Under general anesthesia, the authors exposed the posterior lumbar elements through a midline spinal approach and cannulated six to eight pedicles in each sheep, without the use of radiographic or fluoroscopic guidance. Placement of properly located holes as well as intentionally misdirected holes was attempted. Using the fiber optic endoscope, direct examination of the interior of 22 pedicle screw holes was performed. Nine deliberate and 2 unintentional perforations, for a total of 11 defects in 22 pedicles, were easily recognized. These were confirmed by gross examination after specimens were harvested. Defects as small as 2 mm in diameter, not detected on palpation with a standard probe, were able to be closely inspected. The use of intraosseous endoscopy may serve as a useful adjunct in the placement of pedicle screws.


Subject(s)
Bone Screws , Endoscopy , Lumbar Vertebrae , Animals , Fiber Optic Technology , Lumbar Vertebrae/diagnostic imaging , Lumbar Vertebrae/pathology , Models, Biological , Optical Fibers , Sheep , Tomography, X-Ray Computed
9.
Article in German | MEDLINE | ID: mdl-8471877

ABSTRACT

Several more recent research results in psychosomatic obstetrics and gynecology will be presented, and directions for the practice will be given. In conclusion, it will be discussed how, for the realization of psychosomatic concepts, 'old-fashioned thinking' with biased, monocausal, scientific approaches is unproductive. This concerns, in particular, university gynecological hospitals where psychosomatic thinking is only very hesitantly accepted. The goal is, therefore, to promote a new thinking process, which incorporates an increased consideration of reference points like sensibility, flexibility and creativity.


Subject(s)
Genital Diseases, Female/psychology , Obstetric Labor Complications/psychology , Patient Care Team , Pregnancy Complications/psychology , Psychophysiologic Disorders/psychology , Adaptation, Psychological , Female , Humans , Infant, Newborn , Physician's Role , Pregnancy
10.
Ther Umsch ; 52(2): 114-8, 1995 Feb.
Article in German | MEDLINE | ID: mdl-7892671

ABSTRACT

Only recently a stillbirth has been recognized as a major loss for the majority of women. Based on psychotherapeutic experience and clinical investigations, symptoms and risk factors of normal and pathological courses of grief are delineated and illustrated by a case vignette. Risk factors for complicated grief refer to quality of inpatient care, partner support, previous depression, anxiety or unresolved strain. Recommendations for inpatient care include validating the loss, making it real, enabling the bereaved parents to make informed decisions. Ambulatory after care should provide for monitoring and supporting the grief process.


Subject(s)
Adaptation, Psychological , Fetal Death , Grief , Adult , Depression/psychology , Female , Humans , Interpersonal Relations , Male , Pregnancy
12.
Forensic Sci Int ; 222(1-3): 200-7, 2012 Oct 10.
Article in English | MEDLINE | ID: mdl-22727570

ABSTRACT

A collaborative study on Raman spectroscopy and microspectrophotometry (MSP) was carried out by members of the ENFSI (European Network of Forensic Science Institutes) European Fibres Group (EFG) on different dyed cotton fabrics. The detection limits of the two methods were tested on two cotton sets with a dye concentration ranging from 0.5 to 0.005% (w/w). This survey shows that it is possible to detect the presence of dye in fibres with concentrations below that detectable by the traditional methods of light microscopy and microspectrophotometry (MSP). The MSP detection limit for the dyes used in this study was found to be a concentration of 0.5% (w/w). At this concentration, the fibres appear colourless with light microscopy. Raman spectroscopy clearly shows a higher potential to detect concentrations of dyes as low as 0.05% for the yellow dye RY145 and 0.005% for the blue dye RB221. This detection limit was found to depend both on the chemical composition of the dye itself and on the analytical conditions, particularly the laser wavelength. Furthermore, analysis of binary mixtures of dyes showed that while the minor dye was detected at 1.5% (w/w) (30% of the total dye concentration) using microspectrophotometry, it was detected at a level as low as 0.05% (w/w) (10% of the total dye concentration) using Raman spectroscopy. This work also highlights the importance of a flexible Raman instrument equipped with several lasers at different wavelengths for the analysis of dyed fibres. The operator and the set up of the analytical conditions are also of prime importance in order to obtain high quality spectra. Changing the laser wavelength is important to detect different dyes in a mixture.

13.
Bone ; 49(6): 1186-93, 2011 Dec.
Article in English | MEDLINE | ID: mdl-21884836

ABSTRACT

In order to better understand bone postyield behavior and consequently bone failure behavior, this study aimed first to investigate cortical bone microstructure and second, to relate cortical bone microstructure to microdamage initiation and propagation in C57BL/6 (B6) and C3H/He (C3H) mice; two murine inbred strains known for their differences in bone phenotype. Murine femora of B6 and C3H were loaded axially under compression in a stepwise manner. For each loading step, 3D data sets at a nominal resolution of 700 nm were acquired by means of synchrotron radiation-based computed tomography. Cortical bone microstructure was divided into three phases: the canal network, the osteocyte lacunar system, and microdamage. Canal volume density and canal unit volume both correlated highly to crack number density (canal volume density: R(2)=0.64, p<0.005 and canal unit volume: R(2)=0.75, p<0.001). Moreover, the large canal units in C3H bone were responsible for more microdamage accumulation compared to B6 bones. This more pronounced microdamage accumulation due to large intracortical bone voids, which eventually leads to a fatal macrocrack (fracture), represents a potential contributing factor to the higher incidence of bone fractures in the elderly.


Subject(s)
Femur/pathology , Stress, Mechanical , Animals , Female , Haversian System/pathology , Mice , Mice, Inbred C3H , Mice, Inbred C57BL
20.
Bone ; 45(2): 164-73, 2009 Aug.
Article in English | MEDLINE | ID: mdl-19410668

ABSTRACT

The strength of bone tissue is not only determined by its mass, but also by other properties usually referred to as bone quality, such as microarchitecture, distribution of bone cells, or microcracks and damage. It has been hypothesized that the bone ultrastructure affects microcrack initiation and propagation. Due to its high resolution, bone assessment by means of synchrotron radiation (SR)-based computed tomography (CT) allows unprecedented three-dimensional (3D) and non-invasive insights into ultrastructural bone phenotypes, such as the canal network and the osteocyte lacunar system. The aims of this study were to describe the initiation and propagation of microcracks and their relation with these ultrastructural phenotypes. To this end, femora from the two genetically distinct inbred mouse strains C3H/He (C3H) and C57BL/6 (B6) were loaded axially under compression, from 0% strain to failure, with 1% strain steps. Between each step, a high-resolution 3D image (700 nm nominal resolution) was acquired at the mid-diaphysis using SR CT for characterization and quantitative analysis of the intracortical porosity, namely the bone canal network, the osteocyte lacunar system and the emerging microcracks. For C3H mice, the canal, lacunar, and microcrack volume densities accounted typically for 1.91%, 2.11%, and 0.27% of the cortical total volume at 2% apparent strain, respectively. Due to its 3D nature, SR CT allowed to visualize and quantify also the volumetric extent of microcracks. At 2% apparent strain, the average microcrack thickness for both mouse strains was 2.0 microm for example. Microcracks initiated at canal and at bone surfaces, whereas osteocyte lacunae provided guidance to the microcracks. Moreover, we observed that microcracks could appear as linear cracks in one plane, but as diffuse cracks in a perpendicular plane. Finally, SR CT images permitted visualization of uncracked ligament bridging, which is thought to be of importance in bone toughening mechanisms. In conclusion, this study showed the power of SR CT for 3D visualization and quantification of the different ultrastructural phases of the intracortical bone porosity. We particularly postulate the necessity of 3D imaging techniques to unravel microcrack initiation and propagation and their effects on bone mechanics. We believe that this new investigation tool will be very useful to further enhance our understanding of bone failure mechanisms.


Subject(s)
Femur/pathology , Fractures, Bone/pathology , Animals , Compressive Strength , Diaphyses/diagnostic imaging , Diaphyses/pathology , Femur/diagnostic imaging , Finite Element Analysis , Mice , Mice, Inbred C57BL , Porosity , Synchrotrons , Time Factors , Tomography, X-Ray Computed
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