Biomedical subjects
T Maier
Publications and source records attributed to T Maier.
[Hoarding and severe neglect. A case report].
Severe neglect of the living space due to excessive collection of unusable objects and refuse has been named "Vermuellung" (complete congestion with garbage) since 1985 in the German literature. The internationally used terms 'hoarding' or 'Diogenes syndrome' are in fact neither synonyms nor direct translations of the term. The condition is a problem mainly in social and geriatric psychiatry, yet it is seen also in young subjects without psychopathologic features. A frequent cause for the condition is obsessive-compulsive disorder, but several other disorders are associated with it. A 58-year-old female patient with severe Vermuellung due to obsessive-compulsive disorder is presented.
[Endothelial ion channels -- novel targets for antihypertensive therapy].
Endothelial cation channel are important regulators of vascular tone by modulating intracellular Ca(2+)-signaling and thus adequate synthesis of vasodilating factors. The overall importance of these ion channels suggests that they may represent novel pharmacotherapeutic targets in addition to the well-known voltage-gated calcium channels in vascular smooth muscle. In this short overview we summarize the current knowledge about endothelial ion channels and their roles for endothelium-dependent vasodilatation. Furthermore, we perspectively discuss the usefulness of specific openers of endothelial Ca(2+)-activated K(+)-channels and TRPV-channels as novel antihypertensive drugs.
Sunscreens - which and what for?
It is well established that sun exposure is the main cause for the development of skin cancer. Chronic continuous UV radiation is believed to induce malignant melanoma, whereas intermittent high-dose UV exposure contributes to the occurrence of actinic keratosis as precursor lesions of squamous cell carcinoma as well as basal cell carcinoma. Not only photocarcinogenesis but also the mechanisms of photoaging have recently become apparent. In this respect the use of sunscreens seemed to prove to be more and more important and popular within the last decades. However, there is still inconsistency about the usefulness of sunscreens. Several studies show that inadequate use and incomplete UV spectrum efficacy may compromise protection more than previously expected. The sunscreen market is crowded by numerous products. Inorganic sunscreens such as zinc oxide and titanium oxide have a wide spectral range of activity compared to most of the organic sunscreen products. It is not uncommon for organic sunscreens to cause photocontact allergy, but their cosmetic acceptability is still superior to the one given by inorganic sunscreens. Recently, modern galenic approaches such as micronization and encapsulation allow the development of high-quality inorganic sunscreens. The potential systemic toxicity of organic sunscreens has lately primarily been discussed controversially in public, and several studies show contradictory results. Although a matter of debate, at present the sun protection factor (SPF) is the most reliable information for the consumer as a measure of sunscreen filter efficacy. In this context additional tests have been introduced for the evaluation of not only the protective effect against erythema but also protection against UV-induced immunological and mutational effects. Recently, combinations of UV filters with agents active in DNA repair have been introduced in order to improve photoprotection. This article reviews the efficacy of sunscreens in the prevention of epithelial and nonepithelial skin cancer, the effect on immunosuppression and the value of the SPF as well as new developments on the sunscreen market.
Hertel exophthalmometry versus computed tomography and optical 3D imaging for the determination of the globe position in zygomatic fractures.
It has been the aim of the present study, to introduce the combination of computed tomography and optical 3D imaging to exophthalmometry and to compare the resulting data to the classic Hertel method. Twenty patients without orbital pathology and 12 patients were included in the study, who were subjected to a preoperative computed tomography. Optical 3D images of the facial surface were assessed and Hertel exophthalmometry was carried out to determine protrusion. In patients with zygomatic fractures the assessment of optical 3D images and Hertel values was repeated 5 days after surgery. Preoperative axial CT slices and postoperative optical contours through the globes were superimposed and the change in protrusion was determined. The protrusion values assessed either by CT, Hertel exophthalmometry or optical 3D imaging for patients without orbital pathology did not show any statistically significant differences between each other. For zygomatic fractures, Hertel exophthalmometry revealed more pronounced protrusion data in four of five cases of a posterolaterally dislocated lateral orbital rim and a higher degree of enophthalmos in cases without dislocation of the lateral orbital rim than it could be proved in the CT slices. The differences between optical measurements and CT data were minimal in patients with zygomatic fractures. The combination of computed tomography as baseline measurement and optical 3D imaging for the follow-up examinations reveal more realistic data in cases of zygomatic fractures than Hertel measurements and should be preferred.
On phenomenology and classification of hoarding: a review.
OBJECTIVE: Hoarding is a behavioural abnormity characterized by the excessive collection of poorly usable objects. It is described mainly in association with obsessive-compulsive disorders (OCDs) and in geriatric populations. Yet the literature on the phenomenon is heterogeneous and the notion obviously lacks a consistent definition. This review attempts to describe the psychopathological and clinical spectrum of hoarding and may contribute to clarify its classification. METHOD: Systematic review and discussion of the literature on hoarding. RESULTS: Hoarding is a complex behavioural phenomenon associated with different mental disorders. The psychopathological structure is variously composed of elements of OCDs, impulse-control disorders, and ritualistic behaviour. Severe self-neglect is a possible consequence of hoarding. CONCLUSION: Without further specifications the term hoarding is of limited heuristic value and cannot guide therapeutic interventions satisfactorily. The condition needs to be evaluated carefully in every particular case in relation to the aforementioned psychopathological concepts.
Survival and prognostic factors in patients with brain metastases from malignant melanoma.
AIM: We wanted to determine the factors influencing survival in a retrospective review of patients with melanoma brain metastases to permit more specific recommendations regarding therapy. PATIENTS AND METHODS: We reviewed the data of 100 patients treated at the Department of Dermatology and Radiation Oncology, University of Zurich, and the Klinik im Park, Zurich. Information on potential prognostic factors (age, sex, location of the primary tumor, Clark level, Breslow index, histological type, number of brain metastases, stage at initial diagnosis, location of brain metastases, and therapy) was collected from the medical records of 100 patients treated between 1966 and 2002. Univariate and multivariate analyses were performed to identify significant prognostic factors. RESULTS: The overall median survival time was 4.8 months, with 6-month, 1-year and 2-year survival percentages of 36, 14 and 5%, respectively. Univariate analysis indicated that survival correlated significantly with radiotherapy (partial and whole brain), surgery, stereotactic radiosurgery, chemotherapy, Clark level and Breslow index. Treatment with temozolomide (p = 0.052) and number of brain metastases (p = 0.07) failed to be statistically significant. Multivariate analysis confirmed radiotherapy (partial and whole brain), surgery, stereotactic radiosurgery, chemotherapy and the location of brain metastases as independent and significant prognostic factors of survival. The remaining factors did not reach statistical significance in multivariate analysis. CONCLUSION: Radiotherapy, chemotherapy and especially surgery and stereotactic radiosurgery seem to significantly prolong survival, as shown by multivariate analysis. Treatment with temozolomide will possibly play an important role in the future management of patients with brain metastases from cutaneous melanoma, but further prospective studies to verify this assumption are urgently needed.
Fusion of computed tomography data and optical 3D images of the dentition for streak artefact correction in the simulation of orthognathic surgery.
OBJECTIVE: To determine the limits of accuracy of fusion of optical three-dimensional (3D) imaging and computed tomography (CT) with and without metal artefacts in an experimental setting and to show the application of this hybrid system in 3D orthognathic surgery simulation. METHODS: Ten plaster casts of dental arches were subjected to a CT scan and optical 3D surface imaging. Subsequently, the first molars in the plaster casts were supplied with metal restorations, bilaterally, and new CT scans and optical surface images were assessed. The registration of the surface data of the two imaging modalities of the study models without and with metal restorations was carried out. The mean distance between the two data sets was calculated. From a patient a CT scan of the skull as well as optical 3D images of plaster casts of the dental arches were acquired. Again the two imaging modalities were registered and virtual orthognathic surgery simulation was carried out. RESULTS: The mean distance between the corresponding data points of CT and optical 3D surface images was 0.1262+/-0.0301 mm and 0.2671+/-0.0580 mm, respectively, for the plaster casts without and with metal restorations. The differences between these data were statistically significant (P<0.0005). For the patient case a mean difference of 0.66+/-0.49 mm and 0.56+/-0.48 mm for mandible and maxilla, respectively, was calculated between CT and optical surface data. CONCLUSION: The accuracy of the fusion of 3D CT surface data and optical 3D imaging is significantly reduced by metal artefacts. However, it seems appropriate for virtual orthognathic surgery simulation, as post-operative orthodontics are performed frequently.
[Development of delusion in view of Luhmann's systems theory].
The systems theory of Niklas Luhmann declares itself as a universal theory and therefore claims applicability to any social and psychic phenomenon.In spite of its high complexity, to many it seems too vague and nonspecific. The possible usefulness of this theory should be demonstrated on the example of the development of delusion, still a mysterious and unexplained phenomenon. Within the framework of Luhmann's systems theory, delusion can be considered a communication disorder and therefore a phenomenon within the social system. Both the autopoietic systems society and psyche are based on and processed by meaning but cannot communicate directly, and they are mutually nontransparent and unpredictable. Due to this fact, the interface between the two systems is a potential source of disturbances. Luhmann defines the distinction of information, message, and understanding as the crucial element to connect the social system with the psychic one. If the psychic system fails to recognize the message of an information correctly or is unable to negotiate between understanding and misunderstanding messages, it detaches itself from the social system to which it is normally closely connected. This detachment releases the possibility of unhindered autistic fulfillment of desires and uncontrolled fear. Due to the meaning-based autopoiesis of the psychic system,these released thoughts and emotions still appear in meaningfully condensed form as delusions.
Insect immune activation by apolipophorin III is correlated with the lipid-binding properties of this protein.
Apolipophorin III (apoLp-III) is an exchangeable insect apolipoprotein consisting of five amphipathic alpha-helices. The protein is able to open reversibly on associating with hydrophobic surfaces and plays a role both in lipid transport and induction of immune responses. Point mutations were introduced at positions 66 (N-->D) and/or 68 (K-->E) between helices 2 and 3, a region possibly serving as a hinge for the opening of the molecule when associating with lipids. The lipid-binding properties of the mutant proteins were analyzed and compared with their immune inducing activities. Structural properties of the proteins were studied by far UV circular dichroism spectroscopy and their abilities to form discoidal complexes of dimyristoyl phosphatidylcholine (DMPC) vesicles were investigated. In comparison to wild-type apoLp-III, apoLp-III(N66D/K68E), and apoLp-III(K68E) displayed significantly decreased lipid-binding abilities and immune stimulating activities, while these effects were less noticeable with apoLp-III(N66D). The secondary structure of the double mutant apoLp-III(N66D/K68E) was similar to that of wild-type apoLp-III. A noticeable reduction of alpha-helical content could be observed for the single mutants apoLp-III(N66D) and apoLp-III(K68E), which was accompanied by an increase in percentage amount of beta-turns. The stability of the secondary structure determined by heat denaturation was not affected by mutagenesis. Furthermore, the ability of all proteins to form discoidal complexes of equal size and shape in the presence of dimyristoyl phosphatidylcholine indicated that the mutagenesis did not affect the molecular architecture in the lipid-associated conformation. The relationship between reduced lipid association and reduced immune stimulating activity supports the hypothesis that apoLp-III-induced immune activation is triggered by the conformational change of the protein.
[The practice of compulsory patient commitment].
In Switzerland civil law allows compulsory hospitalization under defined circumstances. It is in the power of municipal authorities to decide on compulsory treatment, though in many of the Swiss cantons this power has been delegated to physicians. This paper first specifies the requirements for medical certificates directing compulsory hospitalization. Then 100 not selected medical certificates from 1997-2000 are compared to these requirements. Only 21% of the certificates met with all the requirements of form and content, nearly half of them showed formal deficiencies. The certificates issued by psychiatrists (n = 44) turned out to be more correct and complete in form and content than the certificates issued by not psychiatric hospital doctors (n = 26) and those issued by general practitioners (n = 30). It seems that not specialized (not psychiatric) doctors, who are rarely confronted with patients requiring compulsory treatment, are overcharged with this delicate and demanding task. To blame is also the passivity of the municipal authorities, who do not exercise their supervision task and seem to be happy having delegated the delicate problem of compulsory hospitalization to physicians.
Molecular characterization of the 56-kDa CYP153 from Acinetobacter sp. EB104.
CYP153 a cytochrome P450 from Acinetobacter sp. EB104 catalyzes the hydroxylation of unsubstituted n-alkanes. We have decided to use the CYP153 system as a model for mechanistic studies on regioselective n-alkane oxidation and the interaction of hydrophobic substrates with soluble enzymes. Here the molecular cloning of the CYP153 gene is reported. Single specific primer PCR was applied to yield the whole gene sequence via chromosomal walks. CYP153 consists of 497 amino acids (M(r) = 56 kDa) and thus represents an unusually long bacterial P450, containing all P450 typical structural elements. It constitutes the new P450 family CYP153. The prolonged N-terminus of about 90 amino acids does not contain a so far known membrane-anchoring sequence but a 28-amino acid long amphipathic helix. The relevance of the remarkably long N-terminus and of other sequence motives like the hydrophobic F-G loop is discussed with respect to substrate binding and recognition.
[Somatoform pain disorder and work disability].
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Pseudogaps in the 2D Hubbard Model.
We study the pseudogaps in the spectra of the 2D Hubbard model using both finite-size and dynamical cluster approximation (DCA) quantum Monte Carlo calculations. At half-filling, a charge pseudogap, accompanied by non-Fermi-liquid behavior in the self-energy, is shown to persist in the thermodynamic limit. The DCA (finite-size) method systematically underestimates (overestimates) the width of the pseudogap. A spin pseudogap is not seen at half-filling. At finite doping, a divergent d-wave pair susceptibility is observed.
Fast elevation of the intramyocellular lipid content in the presence of circulating free fatty acids and hyperinsulinemia: a dynamic 1H-MRS study.
The influence of a short-term elevation of free fatty acids (FFAs) on intramyocellular lipids (IMCL) under hyperinsulinemic conditions was monitored in five healthy male subjects in the course of a 5-hr hyperinsulinemic glucose clamp. During the glucose clamp a lipid emulsion (Intralipid 20(R)) and heparin were administered intravenously. IMCL was quantified in the tibialis anterior (TA) and the soleus (SOL) muscle by (1)H-MRS. A rapid elevation of the IMCL pool was found in both muscles (61% in TA and 22% in SOL) in the 5-hr time period. A control hyperinsulinemic glucose clamp in the same study group, repeated without elevation of circulating FFAs, did not lead to significant changes in IMCL for both muscles. The present study shows for the first time that only the combination of high concentrations of FFAs and insulin lead to marked storage of lipids in skeletal muscle cells in humans. Magn Reson Med 45:179-183, 2001.
NHE1-inhibitor cariporide prevents the transient reperfusion-induced shortening of the monophasic action potential after coronary ischemia in pigs.
During myocardial ischemia intracellular acid load increases as a consequence of anaerobic metabolism. Exchange of excessive protons for sodium via the sodium proton exchanger type 1 (NHE1) is supposed to cause intracellular sodium accumulation. The NHE1 inhibitor cariporide has been shown to inhibit ischemia and reperfusion-induced ventricular fibrillation (VF) but the mechanisms are not fully understood. During early reperfusion transient shortening of the action potential has been reported, which renders the heart susceptible to reentrant arrhythmias. In anesthetized pigs subjected to 10 min of left circumflex coronary artery (LCX) occlusion and reperfusion we have investigated whether NHE1 is involved in reperfusion-induced shortening of the monophasic action potential (MAP) taken with an epicardial probe over the ischemic area. In control pigs (n = 7) a moderate decrease in the duration of the MAP at 50 % repolarization (MAPD50) occurred during ischemia reaching 78.8 +/- 5.0% of the pre-ischemic duration at 5 min (p < 0.01) and 87.3 +/- 7.6 % after 10 min. An additional, transient but marked shortening occurred during the first 2 min of reperfusion, which fully recovered after 4 min. At 50 sec of reperfusion MAPD50 fell to 53.1 +/- 8.2 % of the pre-ischemic value corresponding to 90.1 +/- 20.2 msec of reperfusion-induced shortening. Cariporide, 3 mg/kg i.v. 5 min before occlusion (n = 6), totally prevented reperfusion-induced MAP shortening while having no effect on MAPD50 during ischemia. In conclusion, our data suggest that the immediate, transient, but strong action potential shortening during early reperfusion after 10 min of coronary ischemia is due to the activity of the NHE1.
Molecular characterisation and expression of two venom allergen-like protein genes in Heterodera glycines.
Secretory proteins encoded by genes expressed in the oesophageal gland cells of plant-parasitic nematodes have key roles in nematode parasitism of plants. Two venom allergen-like protein cDNAs (designated hg-vap-1 and hg-vap-2)were isolated from Heterodera glycines gland cell cDNA libraries. Both cDNAs hybridised to genomic DNA of H. glycines in Southern blots. The hg-vap-1 cDNA contained an open reading frame encoding 215 amino acids with the first 25 amino acids being a putative secretion signal. The hg-vap-2 cDNA contained an open reading frame encoding 212 amino acids with the first 19 amino acids being a putative secretion signal. Genes of hg-vap-1 and hg-vap-2 contained four introns, which ranged in size from 44 to 574 bp, and five exons ranging in size from 43 to 279 bp. In situ hybridisation analyses showed that mRNAs of both vap genes accumulated specifically in the subventral gland cells of H. glycines during parasitism. The gland cell-specific expression and presence of predicted secretion signal peptides in both VAPs suggest that these proteins are secreted from the nematode and may play a role in the infection of host plants by this parasite.
Identification of putative parasitism genes expressed in the esophageal gland cells of the soybean cyst nematode Heterodera glycines.
Cloning parasitism genes encoding secretory proteins expressed in the esophageal gland cells is the key to understanding the molecular basis of nematode parasitism of plants. Suppression subtractive hybridization (SSH) with the microaspirated contents from Heterodera glycines esophageal gland cells and intestinal region was used to isolate genes expressed preferentially in the gland cells of parasitic stages. Twenty-three unique cDNA sequences from a SSH cDNA library were identified and hybridized to the genomic DNA of H. glycines in Southern blots. Full-length cDNAs of 21 clones were obtained by screening a gland-cell long-distance polymerase chain reaction cDNA library. Deduced proteins of 10 clones were preceded by a signal peptide for secretion, and PSORT II computer analysis predicted eight proteins as extracellular, one as nuclear, and one as plasmalemma localized. In situ hybridization showed that four of the predicted extracellular clones were expressed specifically in the dorsal gland cell, one in the subventral gland cells, and three in the intestine in H. glycines. The predicted nuclear clone and the plasmalemma-localized clone were expressed in the subventral gland cells and the dorsal gland cell, respectively. SSH is an efficient method for cloning putative parasitism genes encoding esophageal gland cell secretory proteins that may have a role in H. glycines parasitism of soybean.