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T Huber

Publications and source records attributed to T Huber.

At least 19 recordsLinked to original sources
PubMed2006

[Identity and dissociation in cyberspace. A case of dissociative identity disorder associated with internet role playing].

OBJECTIVE: By mediating dissociative experiences, the Internet can challenge the boundaries of people's sense of identity. To illustrate this hypothesis, a case of dissociative identity disorder (DID) is presented. CLINICAL PICTURE: A young unemployed woman created and frequently played several characters in an online game. For more than 2 years she spent up to 12 h a day in the Internet, assuming various personalities, which in return intruded upon her neglected real life. TREATMENT AND OUTCOME: During the course of an inpatient psychotherapeutic treatment, the clinical diagnosis of DID was confirmed by psychometric testing. After 12 weeks of psychotherapy, the patient had managed to identify her fragmented identities as character traits and integrated them into her core personality. She rearranged her real everyday life, found a new job, and reduced her online activities. DISCUSSION: Even though the patient's psychopathology stems from a disposition in terms of a personality disorder with histrionic and narcissistic features, excessive internet role play obviously functioned as a trigger to develop DIS. Conclusively, cyberspace's anonymous interactivity may offer the possibility to explore one's identity while also putting at risk its coherence.

Adult↗
PubMed2006

Greengenes, a chimera-checked 16S rRNA gene database and workbench compatible with ARB.

A 16S rRNA gene database (http://greengenes.lbl.gov) addresses limitations of public repositories by providing chimera screening, standard alignment, and taxonomic classification using multiple published taxonomies. It was found that there is incongruent taxonomic nomenclature among curators even at the phylum level. Putative chimeras were identified in 3% of environmental sequences and in 0.2% of records derived from isolates. Environmental sequences were classified into 100 phylum-level lineages in the Archaea and Bacteria.

Archaea↗
PubMed2005

Dose optimization of contrast-enhanced carotid MR angiography.

The purpose of this work was to compare the diagnostic performance of a single-contrast or a double-contrast dose of carotid contrast-enhanced MR angiography (MRA). One-hundred nineteen patients (mean age 65+/-14.4 years) underwent carotid contrast-enhanced MRA with a standardized protocol (repetition time/echo 3.73 ms/1.38 ms, flip-angle 25 degrees, acquisition-time 19 s, voxel size 1.2 x 1.2 x 0.9 mm3) on a 1.5-T scanner (Sonata, Siemens-Medical-Systems) using a neck phased-array coil. Contrast agent was administered intravenously at a rate of 3.0 ml/s, either as a single dose (n=57; 0.1 mmol/kg body weight) or as a double dose (n=62; 0.2 mmol/kg body weight) of meglumine gadoterate (0.5 M/l), followed by 30 ml saline. Qualitative image analysis was performed on maximum intensity projections using a five-point scale. Signal intensities were measured at three different vascular levels on both sides to assess the contrast-to-noise ratios (CNRs). Image quality was rated as good or excellent in all cases. A double dose did not influence the efficacy of carotid enhancement (CNR single dose 69.12+/-19.8; CNR double dose 70.01+/-20.7; p = 0.81) compared with a single dose. In both dose groups the mean CNRs were inversely related to bodyweight, despite adjusted contrast volumes (p=0.0005). Double-dose contrast-enhanced carotid MRA is not superior to single-dose MRA, as overall diagnostic performance and quantitative contrast enhancement are equal. Being more cost-efficient, a single-dose administration of contrast agent is recommended for MRA of the carotid arteries.

Adult↗
PubMed2005

Hierarchical extensibility in the PEVK domain of skeletal-muscle titin.

Titin is the main determinant of passive muscle force. Physiological extension of titin derives largely from its PEVK (Pro-Glu-Val-Lys) domain, which has a different length in different muscle types. Here we characterized the elasticity of the full-length, human soleus PEVK domain by mechanically manipulating its contiguous, recombinant subdomain segments: an N-terminal (PEVKI), a middle (PEVKII), and a C-terminal (PEVKIII) one third. Measurement of the apparent persistence lengths revealed a hierarchical arrangement according to local flexibility: the N-terminal PEVKI is the most rigid and the C-terminal PEVKIII is the most flexible segment within the domain. Immunoelectron microscopy supported the hierarchical extensibility within the PEVK domain. The effective persistence lengths decreased as a function of ionic strength, as predicted by the Odijk-Skolnick-Fixman model of polyelectrolyte chains. The ionic strength dependence of persistence length was similar in all segments, indicating that the residual differences in the elasticity of the segments derive from nonelectrostatic mechanisms.

Amino Acid Motifs↗
PubMed2005

In vivo culture of IVM/IVF embryos in bovine oviducts by transvaginal endoscopy.

This study was conducted to establish a new approach for in vivo culture of in vitro produced embryos in the bovine oviduct by transvaginal endoscopy. Embryos were in vitro matured, fertilized and cultured for 1-4 days and assigned to groups consisting of 10-30 embryos. Embryos were transferred unilaterally into oviducts of 24 heifers by the means of transvaginal endoscopy. After 3-6 days of in vivo incubation embryos were re-collected. Experiment I aimed to evaluate the capability of embryos to migrate to the uterus. The uterine horns of four animals were flushed first, followed by a combined flushing of both oviducts and uterine horns resulting in collection rates of 31 and 34%, respectively. In experiment II, the transfer of embryos into the oviduct close to ovulation (day 1-2--experiment IIA) or at a more advanced cyclic stage (day 3--experiment IIB) succeeded in the collection of 46 and 34% of the transferred complexes, of which 13 and 37% showed the blastocyst stage. This is the first report of successful recovery of transferable blastocysts by transvaginal endoscopy after tubal in vivo culture in the homologous species of originally in vitro produced embryos.

Animals↗
PubMed2004

Effect of morphological properties of transferred embryonic stages on tubal migration Implications for in vivo culture in the bovine oviduct.

In cattle, there is no practical method, which allows tubal transfer of pre-implantation embryos for routine in vivo culture as it has been established in sheep. The aim of our study was to perform tubal transfer by transvaginal endoscopy in synchronized heifers, in order to expose embryos at various embryonic stages to the physiological mechanisms of migration in the non-ligated oviducts. Various embryonic stages were transferred by transvaginal endoscopy into the oviducts of temporary recipients and were recovered on Day 7. The transfer of embryos in hyaluronate containing medium ("Hyaluronan"), zygotes stripped of cumulus ("Denuded Zygotes"), embryos embedded in cumulus ("Zygotes with Cumulus"), matured oocytes with capacitated spermatozoa ("GIFT") or embryos embedded in Na alginate ("Alginate") led to increasing recovery rates (13, 30, 56, 63 and 71%, respectively). However, the developmental rate on Day 7 was adversely affected (16, 11, 8, 16 and 8%), whereas the blastocyst rate on Day 8 showed more balanced results (17, 14, 18, 21 and 11%). Our data demonstrate that the structural properties of transferred embryos affect tubal migration and are crucial for subsequent in vivo culture. Embryos enclosed in cumulus cells or alginate synchronize more successfully with the oviductal transport systems than denuded stages or embryos in hyaluronate containing medium.

Alginates↗
PubMed2004

Intrafallopian transfer of gametes and early stage embryos for in vivo culture in cattle.

It may be possible to avoid inadequate in vitro culture conditions by incubating gametes or embryos in the oviducts for a short time. Ideally, an optimized procedure should be devised, combining in vitro and in vivo systems, in order to achieve synchronization in cattle. We transferred gametes as well as embryos in various stages of development and placed them into the oviducts. Embryos were recovered on Day 7 by flushing of oviducts and uterine horns. Blastocyst rates were determined on Day 7 and on Day 8. Experimental designs included transfer of in vitro matured cumulus oocyte complexes into previously inseminated heifers (COCs group), transfer of in vitro matured COCs simultaneously with capacitated spermatozoa (GIFTs group), transfer of four to eight cell stage embryos developed in vitro after IVM/IVF (Cleaved Stages group) and a group of solely in vitro produced embryos (IVP control group). Our results indicate that in vivo culture of IVM/IVF embryos in the homologous bovine oviduct has a positive influence on subsequent pre-implantation development. In addition, we have evidence that in vitro maturation and in vivo fertilization cannot be synchronized.

Animals↗
PubMed2004

Portal drained visceral flux, hepatic metabolism, and mammary uptake of free and peptide-bound amino acids and milk amino acid output in dairy cows fed diets containing corn grain steam flaked at 360 or steam rolled at 490 g/L.

Objectives were to measure net fluxes of free (FAA) and peptide bound amino acids (AA) (PBAA) across portal-drained viscera (PDV), liver, splanchnic, and mammary tissues, and of milk AA output of lactating Holstein cows (n = 6, 109 +/- 9 d in milk) as influenced by flaking density of corn grain. Cows were fed alfalfa-based total mixed ration (TMR) containing 40% steam-flaked (SFC) or steam-rolled corn (SRC) grain. The TMR were offered at 12-h intervals in a crossover design. Six sets of blood samples were obtained from indwelling catheters in portal, hepatic, and mammary veins and mesenteric or costoabdominal arteries every 2 h from each cow and diet. Intake of dry matter (18.4 +/- 0.4 kg/d), N, and net energy for lactation were not altered by corn processing. Milk and milk crude protein yields (kg/12-h sampling) were 14.2 vs. 13.5 and 0.43 vs. 0.39 for cows fed SFC or SRC, respectively. The PDV flux of total essential FAA was greater (571.2 vs. 366.4 g/12 h, SEM 51.4) in cows fed SFC. The PDV flux of total essential PBAA was 69.3 +/- 10.8 and 51.5 +/- 13.2 g/12 h for cows fed SFC and SRC, respectively, and differed from zero, but fluxes of individual PBAA rarely differed between treatments. Liver flux of essential FAA was greater in cows fed SRC, but only the PBAA flux in cows fed SRC differed from zero. Splanchnic flux of FAA and PBAA followed the pattern of PDV flux, but variation was greater. Mammary uptake (g/12 h) of total essential FAA was greater in cows fed SFC than SRC (224.6 vs. 198.3, SEM 7.03). Mammary uptake of essential PBAA was 25.0 vs. 15.1, SEM 5.2, g/12 h for cows fed SFC or SRC, respectively, and differed from zero in half of the PBAA. Milk output of EAA was 187.8 vs 175.4, SEM 4.4 g/12 h in cows fed SFC and SRC, respectively, and output of most essential AA consistently tended to be greater in cows fed SFC. It is apparent that PBAA comprise a portion of total AA flux across PDV and are affected by grain processing. Further, this pool supplies an important component of AA taken up by the mammary gland. Quantifying the contribution of PBAA may improve diet formulation with respect to intestinal absorption and mammary uptake of AA.

Amino Acids↗
PubMed2003

36Cl measurements in Hiroshima granite samples as part of an international intercomparison study. Results from the Munich group.

Within the effort to resolve the so-called Hiroshima neutron discrepancy, an international intercomparison study has been carried out on granite samples from Hiroshima, with participating institutions from Japan, the US, and Germany. (36)Cl and (152)Eu produced in these samples by thermal neutrons from the A-bomb explosion were assessed independently by means of different techniques. At the Maier-Leibnitz-Laboratory near Munich, Germany, (36)Cl concentrations were measured by accelerator mass spectrometry. Measured (36)Cl/Cl ratios ranged from 1,670 x 10(-13) (at a distance of 146 m from the hypocenter) to 2.2 x 10(-13) (at a distance of 1,163 m from the hypocenter). One granite sample not exposed to A-bomb neutrons was measured as a control, and a (36)Cl/Cl ratio of 2.6 x 10(-13) was obtained. On average, our experimental results are 20-30% lower than those provided by model calculations based on the dosimetry system DS86. The results presented here do not support previous assessments of (36)Cl, (60)Co, and (152)Eu which had suggested much larger thermal neutron fluences than those calculated on the basis of DS86 for distances from the hypocenter of more than 1,000 m.

Chlorine↗
PubMed2001

The structure of the PII-ATP complex.

PII is a signal transduction protein that is part of the cellular machinery used by many bacteria to regulate the activity of glutamine synthetase and the transcription of its gene. The structure of PII was solved using a hexagonal crystal form (form I). The more physiologically relevant form of PII is a complex with small molecule effectors. We describe the structure of PII with ATP obtained by analysis of two different crystal forms (forms II and III) that were obtained by co-crystallization of PII with ATP. Both structures have a disordered recognition (T) loop and show differences at their C termini. Comparison of these structures with the form I protein reveals changes that occur on binding ATP. Surprisingly, the structure of the PII/ATP complex differs with that of GlnK, a functional homologue. The two proteins bind the base and sugar of ATP in a similar manner but show differences in the way that they interact with the phosphates. The differences in structure could account for the differences in their activities, and these have been attributed to a difference in sequence at position 82. It has been demonstrated recently that PII and GlnK form functional heterotrimers in vivo. We construct models of the heterotrimers and examine the junction between the subunits.

Adenosine Triphosphate↗
PubMed2000

[Behavioral disorders in patients with dementia--somatic causes].

Behavioral disorders in dementia are often caused by somatic diseases. This suggests the importance of a focussed but careful physical examination, especially because it is often difficult to obtain correct anamnestic data. Its a fact that behavioral disturbances in dementia often improve by a successful treatment of somatic problems. This strategy may not only enhance the chance to find a nursing home where the patient can spend his further life but will also improve his quality of life and outcome.

Aged↗
PubMed2000

A new view on chemistry of solids in solution--cryo energy-filtered transmission electron microscopy (cryo-EFTEM) imaging of aggregating palladium colloids in vitreous ice

It is shown that by using cryo-transmission electron microscopy (cryo-TEM) it is possible to image the aggregation behaviour of nanoparticles while they are still in solution. This technique has allowed the study of the arrangement of colloidal palladium particles in solution by preparing the specimen by the plunge-freezing technique. This method of rapidly cooling the specimen avoids rearrangement of the particles during specimen preparation. The palladium particles were identified by energy-filtered cryo-TEM. The aggregation of particles in solution was studied as a function of pH and ionic strength. The results can be used as recommendations for colloidal solutions intended for deposition of single particles.

Journal Article↗
PubMed2000

A (2)H NMR study of macroscopically aligned bilayer membranes containing interfacial hydroxyl residues.

The polar interface of membranes containing phosphatidylglycerol or cholesterol was studied by (2)H nuclear magnetic resonance (NMR) as a function of membrane hydration. The membranes were macroscopically aligned and hydrated with deuterium oxide. Water uptake and membrane annealing was achieved under NMR control, using a novel hydration technique. Well-resolved (2)H quadrupolar doublets were obtained from individual hydroxyl residues and from the interlamellar water. The response of the phosphatidylglycerol headgroup and of the cholesterol molecule to the spontaneous evaporation of interlamellar water could be thus monitored continuously. It is shown that the phosphatidylglycerol headgroup undergoes changes of conformation and average orientation with respect to the membrane surface and that the off-axis motion of the cholesterol molecule decreases. The deuteron exchange between hydroxyl residues and surface-associated D(2)O was determined by an inversion transfer technique. The exchange rates of the hydroxyl residues in the phosphatidylglycerol headgroup were different and depended strongly on the total hydration of the membrane. Significantly lower and almost hydration-independent rates were obtained for cholesterol. These results will be discussed with reference to earlier reports on the headgroup dynamics of phosphatidylglycerol and on the interaction of cholesterol with the membrane-water interface.

Biophysical Phenomena↗
PubMed2000

[Ventilation according to the "open lung" concept of multiple trauma patients].

OBJECTIVE: The ventilation mode clearly influences the course of patients with multiple trauma on the ICU. Ventilation according the "open lung" approach rapidly opens up atelectatic lung regions. Generation of an adequate intrinsic PEEP enables to keep the lung open. We studied the consequences of the "open lung" approach on the lung function and monitored its side effects on patients with multiple trauma. METHODS: 18 consecutive patients with multiple trauma and additional thoracic trauma were routinely ventilated according the "open lung" approach between May and November 1999. We were mainly interested in data of lung mechanics, oxygenation and ventilation. Side effects on other organ systems and consequence for the infection rate were monitored. RESULTS: Ventilation according the "open lung" approach enables early sufficient oxygenation and ventilation of patients with severe multiple trauma and accompanying thoracic trauma. The ventilation mode helps to prevent baro-, volu- and atelectrauma and thus fulfils the requirements for a present-day ventilation mode. An immediate complete healing of the lung damages was not found. Nevertheless, as a trend the length of ventilation support seems short. Even extensive osteosynthesis at multiple fractures was possible without delay. Side effects of the high opening pressure on the lung or other organs as well as sequels of the high intrinsic PEEP on liver, kidney or intestine were not found. The infection rate was low, therapeutic doses of antibiotics were necessary only in less than half of the ICU-stay. CONCLUSION: Ventilation according the "open lung" approach is a very effective and safe way to ventilate patients after severe multiple trauma with accompanying thoracic trauma.

Adolescent↗
PubMed2000

In vitro evaluation of the biofunctionality of osteoblasts cultured on DegraPol-foam.

The biofunctionality of osteoblasts cultured on DegraPol-foam, a biodegradable, elastic, and highly porous polyesterurethane-foam, was determined here to examine the possible use of this structure as bone repair material. Osteoblasts from rat tibia and from the cell line (MC3T3-E1) exhibited relatively high attachment and low doubling time that result in a confluent cell multilayer on the surface of the foam. They produced high concentrations of collagen type I and osteocalcin, and expressed increasing alkaline phosphatase activity. Exposure to 1,25-dihydroxy vitamin D (Vit. D) increased dose- and time-dependent alkaline phosphatase activity and osteocalcin concentration, and decreased the level of collagen type I and cell density. Maximal effects of Vit. D on alkaline phosphatase activity (2.2 fold), osteocalcin (1.5 fold), collagen type I (50% reduction), and on cell density (35% reduction) were found at 100 ng Vit. D ml(-1). Osteoblasts cultured on DegraPol-foam in the presence of Vit. D exhibited more spreading and less spindle-like morphology than cells cultured in the absence of Vit. D. Cell ingrowth into the pores of the foam was not affected by Vit. D treatment. Taken collectively, the osteoblasts, capability of responding to Vit. D confirms the osteoblast compatibility of DegraPol-foam and the possible use of this scaffold in the bone healing process.

Alkaline Phosphatase↗
PubMed1999

Protein fold recognition score functions: unusual construction strategies.

We describe two ways of optimizing score functions for protein sequence to structure threading. The first method adjusts parameters to improve sequence to structure alignment. The second adjusts parameters so as to improve a score function's ability to rank alignments calculated in the first score function. Unlike those functions known as knowledge-based force fields, the resulting parameter sets do not rely on Boltzmann statistics, have no claim to representing free energies and are purely constructions for recognizing protein folds. The methods give a small improvement, but suggest that functions can be profitably optimized for very specific aspects of protein fold recognition. Proteins 1999;36:454-461.

Computing Methodologies↗
PubMed1999

Contribution of copper binding to the inhibition of lipid oxidation by plasmalogen phospholipids.

The role of plasmalogen phospholipids for copper-induced lipid oxidation was evaluated. Using 1H-NMR we observed that the copper (CuSO4)-promoted oxidative degradation of polyunsaturated fatty acids in micellar solution was dose-dependently attenuated by the plasmalogen lysoplasmenylethanolamine from bovine brain (lysoBP-PtdEtn). This was due to a direct interaction of copper ions with the plasmalogen-specific enol ether double bond. The enol ether methine 1H signal decreased on the addition of copper, saturation being reached at a molar ratio of lysoBP-PtdEtn to copper of 1:1. The original 1H signal was recovered almost completely after the addition of EDTA. Enrichment of micelles and low-density lipoproteins (LDLs) with plasmalogen phospholipids led to a decrease in the Cu(II) concentration in the aqueous media. After loading of LDLs in vitro with BP-PtdEtn, the LDL-dependent formation of Cu(I) was decreased, in particular in particles experimentally supplemented with alpha-tocopherol. The suppression of copper-promoted lipid oxidation that was observed in the presence of plasmalogen phospholipids plus alpha-tocopherol was greater than the sum of the protective effects elicited by the two substances alone. In conclusion, the formation of a complex between copper ions and the plasmalogens accounts partly for their inhibition of copper-induced lipid oxidation.

Copper↗