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A Beck

Publications and source records attributed to A Beck.

At least 55 records · Page 3Linked to original sources
PubMed2003

Complete genome sequence of the marine planctomycete Pirellula sp. strain 1.

Pirellula sp. strain 1 ("Rhodopirellula baltica") is a marine representative of the globally distributed and environmentally important bacterial order Planctomycetales. Here we report the complete genome sequence of a member of this independent phylum. With 7.145 megabases, Pirellula sp. strain 1 has the largest circular bacterial genome sequenced so far. The presence of all genes required for heterolactic acid fermentation, key genes for the interconversion of C1 compounds, and 110 sulfatases were unexpected for this aerobic heterotrophic isolate. Although Pirellula sp. strain 1 has a proteinaceous cell wall, remnants of genes for peptidoglycan synthesis were found. Genes for lipid A biosynthesis and homologues to the flagellar L- and P-ring protein indicate a former Gram-negative type of cell wall. Phylogenetic analysis of all relevant markers clearly affiliates the Planctomycetales to the domain Bacteria as a distinct phylum, but a deepest branching is not supported by our analyses.

Adaptation, Physiological↗
PubMed2003

Influence of diclofenac (group of nonsteroidal anti-inflammatory drugs) on fracture healing.

INTRODUCTION: Nonsteroidal antirheumatics (NSAR; NSAID) are often used in patients with fractured bones for analgetic reasons. This animal experiment was performed to determine the influence of NSAR on the process of fracture healing. As an alternative, tramadol, the centrally acting analgetic without peripheral effects, was included in this experiment. MATERIALS AND METHODS: Wistar rats were operated on by a transverse osteotomy of the proximal tibia of the left leg. The fracture was stabilized by intramedullary nailing (healing period 21 days). All drugs were applied orally twice a day. The animals were divided into four groups with 10 rats each: Group 1 was treated with placebo (P), group 2 with tramadol (T; 20 mg/kg body weight/day), group 3 with diclofenac sodium (DS; 5 mg/kg bw/day) for 7 days followed by 14 days of placebo, group 4 with diclofenac sodium (DL; 5 mg/kgbw/day) over 21 days. On day 21 the rats were killed, and each leg was examined by X-ray, then the tibia was examined by CT scan, three-point bending, and histology. RESULTS: The results of CT and three-point bending showed that rats treated by diclofenac presented with delayed fracture healing compared with those treated by placebo or tramadol. Bone density in CT was highest in group 1 (mean 611.4+/-50.1 mg/ml), followed by group 2 (mean 542.5+/-29.5 mg/ml). Groups 3 (mean 411+/-34.0 mg/ml; p=0.006) and 4 (mean 395.2+/-15.4 mg/ml; p=0.009) were significantly lower. The stability of the bones, as measured by the breaking force ( F(max)), was highest in group 1 (mean 45.8+/-19.0 N), followed by group 2 (mean 39.0+/-7.9 N; NS); group 3 (mean 20.6+/-7.8 N; p=0.01) was significantly lower than the placebo animals, followed by group 4 (mean 26.5+/-8.3 N; p=0.03). Similar results were shown for bending stiffness: group 1 (mean 1404.6+/-611.4 Nmm/mm), group 2 (mean 1033.2+/-232.1 Nmm/mm; NS), group 3 (mean 564.2+/-457 Nmm/mm; p=0.045), and group 4 (mean 494.8+/-340.2 Nmm/mm; p=0.028). There were no significant differences between groups 1 and 2 and between groups 3 and 4, respectively. Diclofenac serum levels on day 21 in rats with long-term diclofenac application (mean 301.4+/-83.3 ng/ml) were comparable to those in humans. CONCLUSION: Oral application of diclofenac significantly delayed fracture healing in rats. This effect might be comparable to other NSAR and fracture healing in humans.

Analgesics, Opioid↗
PubMed2003

The immunodominant influenza matrix T cell epitope recognized in human induces influenza protection in HLA-A2/K(b) transgenic mice.

The protective efficacy of the influenza matrix protein epitope 58-66 (called M1), recognized in the context of human HLA-A2 molecules, was evaluated in a HLA-A2/K(b) transgenic mouse model of lethal influenza infection. Repeated subcutaneous immunizations with M1 increased the percentage of survival. This effect was mediated by T cells since protection was abolished following in vivo depletion of all T lymphocytes, CD8(+), or CD4(+) T cells. The survival correlated with the detection of memory CD8(+) splenocytes able to proliferate in vitro upon stimulation with M1 and to bind M1-loaded HLA-A2 dimers, as well as with M1-specific T cells in the lungs, which were directly cytotoxic to influenza-infected cells following influenza challenge. These results demonstrated for the first time that HLA-A2-restricted cytotoxic T cells specific for the major immunodominant influenza matrix epitope are protective against the infection. They encourage further in vivo evaluation of T cell epitopes recognized in the context of human MHC molecules.

Animals↗
PubMed2003

Synthesis, refolding and protective immune responses of a potential antigen for human Respiratory Syncytial Virus vaccine.

The design of new antigens with both high immunogenic and safety properties is of particular interest to vaccine against infectious diseases. In the present study, we describe the synthesis and the refolding of peptide G20 derived from the Human Respiratory Syncytial Virus (hRSV) G-protein. G20 (MEF G140-190 G144-158) is a peptide of 69 amino acids with two disulfide bridges, which comprises multiple protective B-cell epitopes. It was deleted of the T helper cell epitope 184-198 of the RSV G-protein, which was found to induce pulmonary pathology after RSV challenge in mice. Interestingly, we showed in the present study that G20 generated a highly protective antibody response against RSV challenge in Balb/c mice. Therefore, G20 represents a new potential antigen for an RSV vaccine.

Amino Acid Sequence↗
PubMed2003

[Extracapsular spread of cervical lymph node metastases: diagnostic relevance of ultrasound examinations].

OBJECTIVE: Assessment of the value of ultrasound examination in the determination of extracapsular neoplastic infiltration and soft tissue infiltration of cervical lymph nodes. MATERIAL AND METHODS: In a prospective study the results of ultrasound studies in 110 patients with squamous cell carcinoma in the head-neck region were compared with the findings of the histologic examination after neck dissection. RESULTS: Ultrasound examination showed a specificity of 81.8 % in the determination of extracapsular neoplastic infiltration. The sensitivity was only 78.6 % - this was mainly caused by microscopic extracapsular growth, which gave false-negative results. Infiltration of blood vessels were identified in all patients. There was only one false negative diagnosis of muscle infiltration. CONCLUSION: The specificity (81.8 %) and sensitivity (78.6 %) of ultrasound examinations in the diagnosis of extracapsular infiltration in patients with lymph nodes metastasis is promising. But the examiner has to keep in mind that especially microscopic extracapsular neoplastic infiltration cannot be seen in ultrasound.

Carcinoma, Squamous Cell↗
PubMed2003

[Efficacy of stairclimber for muscle strengthening in a closed system after anterior cruciate ligament reconstruction].

UNLABELLED: In a prospective study we investigated the value regarding muscle strength of two stairclimbers with either coupled or non-coupled pedals at either high or low stepping frequency. Following autologous patellar tendon graft surgery 14 patients for each group completed a strict exercising program. After 6 weeks of training a clear advantage was found for the group stepping at low speed with coupled pedals when measuring: At 60 degree/s the average maximum torque of extension increased from 37.7 to 61.7% as compared to a control group (30 to 47.2%). Analogous the percent ratio of flexion/extension (H/Q ratio) improved significantly. During the second training period the improvement of the extension strength as well as the H/Q ratio was found to be only marginal. No negative effects of this type of training on ligament stability could be detected. CONCLUSIONS: Regarding a faster recovery of muscle strength and the improvement of the intermuscular coordination, the stairclimber training, beginning with week 7 after surgery and lasting over a period of 6 weeks, is considered advantageous, especially when exercising is done at low speed and with coupled pedals.

Adolescent↗
PubMed2003

Psychosocial predictors of HIV/STI risk behaviours in a sample of homosexual men.

OBJECTIVES: To determine the prevalence of STI/HIV risk behaviours in a sample of homosexual men and investigate the psychosocial and cognitive variables associated with these behaviours. METHOD: A sample of 123 users of a homosexual men's sexual health clinic completed a questionnaire which included demographic information, psychometric measures, history of sexual risk behaviour, and history of non-consensual sex (NCS). RESULTS: High rates of sexual risk were found in this sample behaviour (36% of men had risky sex in the previous month) despite using a narrower definition than other recent studies. Comparable rates of non-consensual sex were found in this sample (26% of the sample had experienced NCS); however, this variable was not directly linked to increased risk behaviour. Depression and cognitions associated with controllability or predictability of risk were associated with increased HIV/STI risk behaviour. CONCLUSIONS: Clinical measures of depression are associated with risk behaviour in this sample as are cognitions about the uncontrollability of risk and reducing chances of exposure to HIV by insertive sexual practices and fidelity. Demographic variables, a history of non-consensual sex and depression are not predictors of risk behaviour when sexual risk cognitions are used to predict unsafe sexual practices indicating that cognitions are foremost in driving risk behaviours, demographic variables, and the NCS history of the subject. Given the considerable costs of providing medical care to patients with HIV it is likely that even modest reductions in rates of HIV infection through proactive psychological interventions to modify erroneous cognitions will prove highly cost effective.

Adult↗
PubMed2002

The genome sequence of Schizosaccharomyces pombe.

We have sequenced and annotated the genome of fission yeast (Schizosaccharomyces pombe), which contains the smallest number of protein-coding genes yet recorded for a eukaryote: 4,824. The centromeres are between 35 and 110 kilobases (kb) and contain related repeats including a highly conserved 1.8-kb element. Regions upstream of genes are longer than in budding yeast (Saccharomyces cerevisiae), possibly reflecting more-extended control regions. Some 43% of the genes contain introns, of which there are 4,730. Fifty genes have significant similarity with human disease genes; half of these are cancer related. We identify highly conserved genes important for eukaryotic cell organization including those required for the cytoskeleton, compartmentation, cell-cycle control, proteolysis, protein phosphorylation and RNA splicing. These genes may have originated with the appearance of eukaryotic life. Few similarly conserved genes that are important for multicellular organization were identified, suggesting that the transition from prokaryotes to eukaryotes required more new genes than did the transition from unicellular to multicellular organization.

Base Sequence↗
PubMed2002

[Time optimized modern shock room management using digital techniques].

Emergency room management means time management. A time and four color based algorithm is described to improve workflow, follow up of diagnostic procedures and initial treatment. As a result introducing the time based interdisciplinary emergency algorithm within 60 minutes all necessary treatment and diagnostic procedures were completed. This algorithm is an effective tool to improve emergency room treatment.

Algorithms↗
PubMed2002

[Emergency treatment of penetrating, combined thoracic- and abdominal injury. Pre-hospital i.v. fluid therapy].

We report the rare case of a penetrating, combined thoracic- and abdominal injury as a consequence of a farm work accident. During the recent years, a "treat and run" approach has been increasingly advocated as a time-saving way of treating penetrating injuries, constituting a compromise between the existing strategies of "scoop and run" (used mainly in the USA) and "stay and treat" (preferred in Central Europe). A prolonged rescue response time makes the treat and run approach impossible here. Immediate treatment at the accident site requires an appropriate provision of i.v. fluids. We examine the course of pre-hospital treatment of a trauma patient to illustrate the various approaches to i.v. fluid therapy in relation to rescue response time. However there are only a few studies with a real evidence. If "treat and run" is not possible, the outcome of patients with penetrating trauma can be influenced positively by moderate fluid therapy under continuous monitoring after having reached a constant, low mean arteria pressure (so called permissive hypotension).

Abdominal Injuries↗
PubMed2002

[Analysis of the incidence and causes of mass casualty events in a southern Germany medical rescue area].

UNLABELLED: The growing number of mass casualty events during the early 1990s led, in January 1996, to the foundation of an honorary group of specially trained emergency physicians for dealing primarily with the management of large-scale emergency events and mass casualties. The incidence and quantity of these casualties was analysed in order to be better prepared for such events in the future. METHODS: All calls prospectively registered by the Augsburg Rescue Co-ordination Centre (ARCC) in the 5 years from July 1997 to June 2002 were analysed, distinguishing between the different types of damage, number of patients involved, and time of occurrence (time of day/season). The area served by the ARCC includes the city of Augsburg with its surrounding counties. An estimated 850,000 inhabitants live in this area of 4,100 square kilometers (1,600 square miles). Since 1998, more than 145,000 calls a year have been dealt with of which 28,000 were covered by emergency physicians. In the 5 year period discussed here, 75 large-scale-calls were registered, giving an average incidence of 1.25 calls/month. Most of the calls were fire alarms, followed by car accidents. In total, we were able to serve more than 800 patients. The lowest number per event was two people during an emergency landing of a sport aircraft; the largest number was about 150 patients during a large open-air event in the city. While there was no difference in the time of day at which the event happened, most occurred in November and December. Taking these results into account, the authors, supported by the members of the emergency physician team of the German Trauma Society, developed an algorithm describing the optimal procedure for mass casualty events. This is presented here. In mass casualty or large-scale emergency events, an experienced emergency physician is necessary to co-ordinate the rescue brigades on site.

Algorithms↗
PubMed2002

[Costs for acute, stationary treatment of polytrauma patients].

Are the costs required for a polytraumatised patient sufficiently paid by the health care companies?The study population consisted of 71 polytrauma patients. The treatment-costs were calculated and compared with the reimbursements. The mean patient age was 38.0 years with a mean injury severity score (ISS) of 23.0 points. The mean duration of hospitalisation was 25.9 days and the mean calculated cost per patient was Euro 21,866.30. The reimbursement was only Euro 16,863.03/patient. This leads to a financial deficit of approximately Euro 5,000/patient (Euro 167/polytrauma patient/hospital day) and nearly Euro 355,000 for all patients during the period of 1 year. The introduction of the DRG system endangers the high standard of polytrauma treatment because of insufficient reimbursement.It is necessary to consider the implementation of an additional polytrauma-reimbursement based on the injury severity and duration of hospitalisation. The concentration of the patients in trauma centres, where the optimum of therapy is guarantied, leads in these hospitals to a continuously increasing deficit. The latter may be deleterious for the concept of "trauma centers" in the future.

Adult↗
PubMed2002

Structure-antigenicity relationship studies of the central conserved region of human respiratory syncytial virus protein G.

BBG2Na is a recombinant protein, composed in part of carrier protein BB and of the central conserved domain of the attachment glycoprotein G of human respiratory syncytial virus (HRSV) subgroup A. This protein is a potent vaccine candidate against HRSV. G2Na contains several contiguous B-cell epitopes, occupying sequential positions in the linear sequence of the protein. One of the epitopes contains four cysteines that are completely conserved in known strains of HRSV and form a 'cysteine noose' motif. In this study, we analysed circular dichroism (CD) spectra of BBG2Na and its B-cell epitopes. We also used NMR and molecular dynamics simulations to determine the three-dimensional structure of the cysteine noose domain. We observed significant structural differences related to the length of peptides containing the cysteine noose. These differences show good correlation with the immunogenic activity of the peptides. It is shown that a single Val(171) addition induces a pronounced structure stabilization of the cysteine noose peptide G4a (1-4/2-3) (residues 172-187), which is associated with a 100-fold increase in its antigenicity vis-à-vis a G-protein specific monoclonal antibody.

Antigens, Viral↗
PubMed2002

Calcium influx into dendrites of the leech Retzius neuron evoked by 5-hydroxytryptamine.

5-Hydroxytryptamine (5-HT) is a ubiquitous neurotransmitter and neuromodulator that affects neural circuits and behaviours in vertebrates and invertebrates. In the present study, we have investigated 5-HT-induced Ca(2+) transients in subcellular compartments of Retzius neurons in the leech central nervous system using confocal laser scanning microscopy, and studied the effect of 5-HT on the electrical coupling between the Retzius neurons. Bath application of 5-HT (50mM) induced a Ca(2+) transient in axon, dendrites and cell body of the Retzius neuron. This Ca(2+) transient was significantly faster and larger in dendrites than in axon and cell body, and was half-maximal at a 5-HT concentration of 5-12mM. The Ca(2+) transient was suppressed in the absence of extracellular Ca(2+) and by methysergide (100mM), a non-specific antagonist of metabotropic 5-HT receptors, and was strongly reduced by bath application of the Ca(2+) channel blocker Co(2+) (2mM). Injection of the non-hydrolysable GTP analogue GTPgammaS increased and prolonged the dendritic 5-HT-induced Ca(2+) transient. The non-selective protein kinase inhibitor H7 (100mM) and the adenylate cyclase inhibitor SQ22536 (500 mM) did not affect the Ca(2+) transient, and the membrane-permeable cAMP analogue dibutyryl-cAMP (500 mM) did not mimic the effect of 5-HT application. 5-HT reduced the apparent electrical coupling between the two Retzius neurons, whereas suppression of the Ca(2+) influx by removal of external Ca(2+) improved the transmission of action potentials at the electrical synapses which are located between the dendrites of the adjacent Retzius neurons. The results indicate that 5-HT induces a Ca(2+) influx through calcium channels located primarily in the dendrites, and presumably activated by a G protein-coupled 5-HT receptor. The dendritic Ca(2+) increase appears to modulate the excitability of, and the synchronization between, the two Retzius neurons.

Animals↗
PubMed2002

[Extracapsular spread of cervical lymph node metastases: Diagnostic value of magnetic resonance imaging].

OBJECTIVE: Assessment of the value of magnetic resonance tomography in the determination of extracapsular neoplastic spread and soft tissue infiltration of cervical lymph nodes. MATERIALS AND METHODS: The results of magnetic resonance tomographies of 110 patients with squamous cell carcinoma in the head-neck region were prospectively compared with the findings of the histologic examination after neck dissection. RESULTS: Magnetic resonance tomography reaches a specificity of 72.2 % in the detection of extracapsular neoplastic spread. The sensitivity of the method is 74.4 %. Mainly small (less than 1 cm; n = 11) extracapsular growth was not detected and was diagnosed false-negative in the MRI examinations. CONCLUSION: The specificity (72.2 %) and sensitivity (74.4 %) of MRI examinations to detect extracapsular spread of lymph nodes is only partially satisfying.

Adult↗
PubMed2002

[System continuity and energy distribution in laser-induced thermo therapy (LITT)].

PURPOSE: Evaluation of the continuity and energy distribution of a laser system for laser-induced thermo therapy. MATERIAL AND METHODS: For evaluation of the continuity of laser optical devices, laser generating units and optical fibers of three different manufactures (Dornier, Hüttinger, Somatex), we used the equipment to generate a laser beam of 25 Watt for 60 minutes. Measurements of the applied energy were done sequentially with two MY Test (Fa. Hüttinger) units. We also performed two in vitro ablations of animal liver tissue with different fiber optics [Mikrodom A 13-0540, Microflexx REF A 13-0561 (Hüttinger), Diffusor-Tip H-6111-T 3, Diffusor H-6111-T 4 (Dornier), Somaflex-Diffusor (Somatex)] over 20 minutes at- an energy flow of 25 J per second. We then evaluated the geometry of coagulation. RESULTS: The different equipment used for our tests showed differences of a maximum of 10 %. Some components did not work properly in certain configurations even though the manufacturer assured it would. We saw significant differences in the ablation characteristics of the different fiber optics, especially in axial and frontal directions. CONCLUSION: Knowledge of the different characteristics in energy distribution and ablation characteristics are an important factor in performing a successful laser-induced thermo therapy.

Animals↗