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11.
Although it is known that men and women differ in their music preferences and emotional reactions to music, little is known about sex differences in physiological reactions to music. In our study, we therefore set out to examine the differential reactivity to two musical stimuli that elicit distinct psychological and physiological reaction patterns. Fifty-three healthy subjects (mean age: 26.13, SD: 3.97; 26 males, 27 females) were examined. Heart rate, electrodermal activity, skin temperature, salivary cortisol, salivary alpha-amylase, and psychological variables were assessed during the course of the whole study. Following baseline assessment, two musical stimuli, which were carefully selected and rated in a pre-study as relaxing and pleasant (renaissance music) and arousing and unpleasant (heavy metal), respectively, were introduced. They were presented on two different days in a randomized order. Whereas psychological variables did not differ between men and women, results of electrophysiological measures indicate significantly different reactivity patterns between men and women. Women displayed elevated response curves to the arousing and unpleasant stimulus, whereas men did not. However, no differences were found with regards to endocrine measures in saliva. Our results demonstrate sex differences in reactivity patterns to musical stimuli in psychophysiological measures. In our study, we were able to show that women tend to show hypersensitivity to aversive musical stimuli. This finding is in accordance with previous literature on sex differences in emotion research. Furthermore, our study indicates that the confounding effects of sex differences have to be considered when using musical stimuli for emotion induction.  相似文献   
12.
Transplantation of retinal pigment epithelial (RPE) cells is discussed as a possible therapeutic approach for retinal degeneration. Xenogeneic transplantation of human RPE cells in animal models has been studied extensively. Various methods have been used to identify the graft cells, but these methods interfere with cell behaviour so that the monitored physiological post-transplantation course may be influenced. In the present study, we applied a method for an unequivocal identification of the graft cells without interfering cell metabolism or behaviour using in situ hybridisation (ISH) of human specific Alu sequences. Visualisation of the strong extended nuclear signal of Alu sequences was much easier than that of the small nuclear signals of donor-specific sex chromosome probes. With Alu probe, even single graft cells can be identified and their development can be observed in short-term and long-term studies. With this procedure, we could prove that donor cells were injected correctly into the subretinal space by a special injection technique that we developed previously. In combination with immunohistochemistry, donor cells could be clearly discriminated from macrophages, which contained phagocytosed donor cell fragments. Application of these ISH methods for species-specific identification was valuable for follow-up-studies of RPE transplantation.  相似文献   
13.
Histone lysine methylation is a central modification to mark functionally distinct chromatin regions. In particular, H3-K9 trimethylation has emerged as a hallmark of pericentric heterochromatin in mammals. Here we show that H4-K20 trimethylation is also focally enriched at pericentric heterochromatin. Intriguingly, H3-K9 trimethylation by the Suv39h HMTases is required for the induction of H4-K20 trimethylation, although the H4 Lys 20 position is not an intrinsic substrate for these enzymes. By using a candidate approach, we identified Suv4-20h1 and Suv4-20h2 as two novel SET domain HMTases that localize to pericentric heterochromatin and specifically act as nucleosomal H4-K20 trimethylating enzymes. Interaction of the Suv4-20h enzymes with HP1 isoforms suggests a sequential mechanism to establish H3-K9 and H4-K20 trimethylation at pericentric heterochromatin. Heterochromatic H4-K20 trimethylation is evolutionarily conserved, and in Drosophila, the Suv4-20 homolog is a novel PEV modifier to regulate position-effect variegation. Together, our data indicate a function for H4-K20 trimethylation in gene silencing and further suggest H3-K9 and H4-K20 trimethylation as important components of a repressive pathway that can index pericentric heterochromatin.  相似文献   
14.
Human defensins   总被引:7,自引:0,他引:7  
Antimicrobial peptides are small, cationic, amphiphilic peptides of 12–50 amino acids with microbicidal activity against both bacteria and fungi. The eukaryotic antimicrobial peptides may be divided into four distinct groups according to their structural features: cysteine-free -helices, extended cysteine-free -helices with a predominance of one or two amino acids, loop structures with one intramolecular disulfide bond, and -sheet structures which are stabilised by two or three intramolecular disulfide bonds. Mammalian defensins are part of the last-mentioned group. The mammalian defensins can be subdivided into three main classes according to their structural differences: the -defensins, -defensins and the recently described -defensins. Mammalian -defensins are predominantly found in neutrophils and in small intestinal Paneth cells, whereas mammalian -defensins have been isolated from both leukocytes and epithelial cells. Recently, two novel human -defensins, human beta-defensin-3 (HBD-3), and human beta-defensin-4 (HBD-4) have been discovered. Similar to HBD-1 and HBD-2, HBD-3 has microbicidal activity towards the Gram-negative bacteria (Pseudomonas aeruginosa, Escherichia coli) and the yeasts Candida albicans and Malassezia furfur. In addition, HBD-3 kills Gram-positive bacteria such as Streptococcus pyogenes or Staphylococcus aureus, including multi-resistant S. aureus strains, and even vancomycin-resistant Enterococcus faecium. In contrast to HBD-1 and HBD-2, significant expression of HBD-3 has been demonstrated in non-epithelial tissues, such as leukocytes, heart and skeletal muscle. HBD-4 is expressed in certain epithelia and in neutrophils. Its bactericidal activity against P. aeruginosa is stronger than that of the other known -defensins. Here we present an overview of human antimicrobial peptides with some emphasis on their antifungal properties.J.J. Schneider and A. Unholzer contributed equally to this work  相似文献   
15.
The aim of this study was to establish whether the rate of fatty acid (FA) incorporation and its utilization by the isolated soleus muscle is modified under conditions of thyroid hormone deficit or excess. The rate of palmitic acid (PA) uptake, oxidation and incorporation into intramuscular lipids with increasing PA concentration (0.5–1.5 mM) in the incubation medium were determined. In hypothyroid rats intramuscular triacylglycerol (TG) synthesis was increased, while the rate of PA oxidation to CO2 and incorporation into mono- and diacylglycerols (MG/DG) and phospholipids (PL) remained unchanged. In rats with triiodothyronine (T3) excess the rate of all processes studied was enhanced, although the percentage incorporation of PA into different classes of intramuscular lipids was fairly constant and, independently of thyroid state and FA concentration in the medium, was 56–66% for TG, 9-14% for MG/DG and 24–32% for PL. Our results thus indicate that even short-term T3 excess accelerates the rate of FA uptake and metabolism in the oxidative soleus muscle, whereas in hypothyroid rats only intramuscular TG synthesis is affected.  相似文献   
16.

Background  

Previous publications indicate that acupuncture is efficient for the treatment of pelvic girdle pain, PGP, in pregnant women. However, the use of acupuncture for PGP is rare due to insufficient documentation of adverse effects of this treatment in this specific condition. The aim of the present work was to assess adverse effects of acupuncture on the pregnancy, mother, delivery and the fetus/neonate in comparison with women that received stabilising exercises as adjunct to standard treatment or standard treatment alone.  相似文献   
17.
We employ diffuse optical tomography (DOT) to track treatment progress in a female subject presenting with locally advanced invasive carcinoma of the breast during neoadjuvant chemotherapy. Three-dimensional images of total hemoglobin concentration and scattering identified the tumor. Our measurements reveal tumor shrinkage during the course of chemotherapy, in reasonable agreement with magnetic resonance images of the same subject. A decrease in total hemoglobin concentration contrast between tumor and normal tissue was also observed over time. The results demonstrate the potential of DOT for measuring physiological parameters of breast lesions during chemotherapy.  相似文献   
18.
Zusammenfassung Die Wirkungen von Eserin, Cholin und Glucose auf die Freisetzung und die Synthese von Acetylcholin (ACh) wurden im isolierten Dünndarm des Meerschweinchens durch Bestimmungen des ACh-Gehaltes des Gewebes und der ACh-Freisetzung in die Badelösung untersucht.In Lösungen, die Eserin, Cholin und Glucose enthielten, nahm der ACh-Gehalt des Gewebes zu, und es erfolgte eine Freisetzung von ACh in die Badelösung. Die Zunahme des ACh-Gehaltes des Gewebes, welche nur in Eserin-haltigen Lösungen auftrat, konnte auf intracelluläre Anhäufung von ACh zurückgeführt werden.ACh wurde auch in Cholin-freien Lösungen synthetisiert, doch war die ACh-Synthese geringer als in Gegenwart von Cholin. Aus der ACh-Synthese in Cholinfreier Lösung und dem Anteil des Nervengewebes am Darmvolumen wurde die Cholinkonzentration im Nervengewebe berechnet. Es zeigte sich, daß die intracelluläre Cholinkonzentration viel größer als die Cholinkonzentration im Plasma war. Die Cholinaufnahme in das Nervengewebe scheint deshalb in vivo durch aktiven Transport zu erfolgen.Bei Fehlen von Glucose trat keine Synthese von ACh auf, die Freisetzung von ACh hingegen war etwa doppelt so groß wie in Glucose-haltiger Lösung. Die Erhöhung der ACh-Freisetzung nach Glucose-Entzug könnte eine Anzahl der Symptome des hypoglykämischen Schockes erklären.
Summary The effects of eserine, choline, and glucose on the liberation and the synthesis of acetylcholine (ACh) were studied in the guinea pig's small intestine by measuring the ACh content of the tissue and the amount of ACh liberated in the bath.Incubation in solutions containing eserine, choline, and glucose caused an increase in the ACh content of the tissue and the liberation of ACh. The increase in tissue content, which was only found when eserine was present, appears to result from intracellular accumulation of ACh.ACh was also synthezised in choline free solution, but the amounts were smaller than in the presence of choline. Estimation of the choline concentration in the nervous tissue, from the ACh synthesis in choline free solution and the amount of nervous tissue in the intestine, shows that the choline concentration in nerve is much higher than in plasma. It is suggested that uptake of choline in vivo necessitates an active transport process.No synthesis of ACh was found in the absence of glucose; the liberation of ACh was increased and occured entirely on account of the initial ACh content. The increase in ACh liberation after glucose withdrawal might explain some symptoms of hypoglycemic shock.


Mit 4 Textabbildungen

Mit Unterstützung der Deutschen Forschungsgemeinschaft.  相似文献   
19.
Obesity is a serious health problem in industrialized countries and is associated with a significant increase in total health care costs. Only few data are available about the costs of drug therapies in patients with an increased body weight treated under clinical routine procedures. Such data could support efforts to intensify obesity prevention and treatment programmes in order to reduce comorbidities and costs. We have evaluated body mass index (BMI), diagnosis, and medication in 3360 outpatients (2175 women and 1185 men; mean age: 56.7 +/- 17.5 years). All patients underwent physical examinations, including BMI determination, and provided a detailed record concerning medication. In 1809 patients, the percentage of body fat content was measured with a bioimpedance method (OMRON BF 302 body fat monitor). Continuous variables were compared using the t-test or Wilcoxon U-test. Frequency distributions were compared using chi-squared tests. With respect to BMI, most of the patients (n = 1793; 53 %) were overweight or obese, 1349 (40 %) showed a normal BMI and 218 (7 %) a low BMI. The majority of cardiovascular (61 %), rheumatological (61.1 %) and metabolic (60.4 %) medication was administered to overweight and obese patients. Parallel findings could be obtained by analysing the percentage of body fat and the frequency of medication. Overall, 82.5 % of all medication was given to patients with a body fat content >20 %. Our results support the importance of weight-reduction programmes in order to prevent an overall increase in the costs of medication as a consequence of overweight and obesity.  相似文献   
20.
The application of texture analysis (TA) in magnetic resonance imaging (MRI) requires the availability of texture phantoms for use in the standardization of in vivo measurements. The aims of our study were (a) to develop a new type of phantoms suitable for MRI and TA and test their long-term stability; (b) to optimize the choice of texture parameters describing the phantoms; (c) to compare different MR imagers according to texture parameters in a multi-center study. A long-term study performed at 4.7 T proved that the developed phantom based on polystyrene spheres and an agar gel solution is stable at least 12 months. This phantom, with nodular patterns, was found useful for the modeling of structural differences. The comparison of TA parameters at 4.7 and 7 T proved that the same parameters can be used for the separation of structures. The proposed algorithm of the selection of TA parameters shows that there exists a part of texture parameters which can be measured with high reproducibility (1-3%); on the other hand, their absolute values can differ by more than 30% if the textures differ. Results obtained from the multi-center study of whole body MR imagers show the wide variation in the misclassification rates at the different sites and point out the importance of the set up of MR sequences.  相似文献   
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