Kognition und Kraftfahreignung bei chronischem Schmerzsyndrom

Kognitive Auffälligkeiten bei Patienten mit chronischen Schmerzen finden in wissenschaftlichen Untersuchungen zunehmend Beachtung. Die Folgen dieser kognitiven Störungen in Bezug auf die Schmerzbewältigung, die Alltagsgestaltung und die Kraftfahreignung werden in der klinischen Praxis jedoch kaum berücksichtigt, obwohl die Hälfte aller Patienten davon betroffen ist. Die vorliegende Arbeit fasst die aktuelle Studienlage zusammen und diskutiert Möglichkeiten der Integration in die klinische und therapeutische Versorgung.

Climatic, geomorphologic and hydrologic perturbations as drivers for mid- to late Holocene development of ice-wedge polygons in the western Canadian Arctic

Ice-wedge polygons are widespread periglacial features and influence landscape hydrology and carbon storage. The influence of climate and topography on polygon development is not entirely clear, however, giving high uncertainties to projections of permafrost development. We studied the mid- to late Holocene development of modern ice-wedge polygon sites to explore drivers of change and reasons for long-term stability. We analyzed organic carbon, total nitrogen, stable carbon isotopes, grain size composition and plant macrofossils in six cores from three polygons. We found that all sites developed from aquatic to wetland conditions. In the mid-Holocene, shallow lakes and partly submerged ice-wedge polygons existed at the studied sites. An erosional hiatus of ca 5000 years followed, and ice-wedge polygons re-initiated within the last millennium. Ice-wedge melt and surface drying during the last century were linked to climatic warming. The influence of climate on ice-wedge polygon development was outweighed by geomorphology during most of the late Holocene. Recent warming, however, caused ice-wedge degradation at all sites. Our study showed that where waterlogged ground was maintained, low-centered polygons persisted for millennia. Ice-wedge melt and increased drainage through geomorphic disturbance, however, triggered conversion into high-centered polygons and may lead to self-enhancing degradation under continued warming.

[Tropheryma whipplei endocarditis]

Whipple's disease is a rare infectious disease caused by the bacterium Tropheryma whipplei. Usually the course of the disease is characterized by fever, diarrhea, weight loss and polyarthritis. We report on a case with a 10-year course of the disease with endocarditis, myocarditis and involvement of the bone marrow but with negative histological results of the small intestine.

Genotypic and phenotypic characterization of Bordetella pertussis strains used in different vaccine formulations in Latin America

AIM

To characterize Bordetella pertussis vaccine strains in comparison with current circulating bacteria.

METHODS AND RESULTS

Genomic and proteomic analyses of Bp137 were performed in comparison with other vaccine strains used in Latin America (Bp509 and Bp10536) and with the clinical Argentinean isolate Bp106. Tohama I strain was used as reference strain. Pulse-field gel electrophoresis (PFGE) and pertussis toxin promoter (ptxP) sequence analysis revealed that Bp137 groups with Bp509 in PFGE group III and contains ptxP2 sequence. Tohama I (group II) and Bp10536 (group I) contain ptxP1 sequence, while Bp106 belongs to a different PFGE cluster and contains ptxP3. Surface protein profiles diverged in at least 24 peptide subunits among the studied strains. From these 24 differential proteins, Bp10536 shared the expression of ten proteins with Tohama I and Bp509, but only three with Bp137. In contrast, seven proteins were detected exclusively in Bp137 and Bp106.

CONCLUSIONS

Bp137 showed more features in common with the clinical isolate Bp106 than the other vaccine strains here included.

SIGNIFICANCE AND IMPACT OF THE STUDY

The results presented show that the old strains included in vaccines are not all equal among them. These findings together with the data of circulating bacteria should be taken into account to select the best vaccine to be included in a national immunization programme.

Blood pressure measurement with the tail-cuff method in Wistar and spontaneously hypertensive rats: influence of adrenergic- and nitric oxide-mediated vasomotion

INTRODUCTION

Systolic blood pressure (SBP) is still measured in rats by the tail-cuff method, allowing readings when pulse/flow disappears during cuff inflation and reappears during deflation, separated by a compression interval. Although cuff deflation is habitually used to estimate SBP, we found cuff deflation-cuff inflation pressure to be usually negative, indicating that cuff deflation pressure < cuff inflation pressure.

METHODS

SBP was measured in 226 male Wistar and SHR utilizing compression intervals of different durations, and also pharmacological interventions intended to modulate the cuff deflation-cuff inflation cycle. Direct, simultaneous intravascular measurements were also performed in some animals.

RESULTS AND DISCUSSION

With compression interval congruent with 15 s, cuff deflation-cuff inflation was--6 +/- 0.6 mmHg in 73 Wistar and--6 +/- 1.4 mmHg in 51 SHR. Lengthening compression interval up to 4 min increased cuff deflation-cuff inflation pressure significantly to--27 +/- 3 mmHg in Wistar and to - 31 +/- 5 mmHg in SHR, suggesting accumulation of a vasodilating mediator. This increase of cuff deflation-cuff inflation pressure was prevented by papaverine (totally in Wistar, partially in SHR), indicating its dependence on vasodilatory capacity. Adrenergic blockade decreased cuff deflation-cuff inflation pressure to--13 +/- 5 mmHg (P < 0.05) in SHR, but had no effect in Wistar rats. Injection of L-NAME decreased cuff deflation-cuff inflation pressure to--5 +/- 2 mmHg (P < 0.05) in Wistar rats but was ineffective in SHR. Simultaneous measurements by tail-cuff method and carotid cannulation revealed that the cuff inflation most accurately estimated the intravascular SBP.

CONCLUSIONS

1) Cuff inflation measurements should be considered representative of SBP, as cuff deflation can underestimate SBP depending on compression interval duration, 2) nitric oxide accumulation due to flow deprivation is the main cause of SBP underestimation by cuff deflation in Wistar, and 3) in SHR, nitric oxide effects were minimal, and sympathetic activation plus physical factors seemed to predominate in the determining the outcome of measurements.

Patient-prosthesis mismatch and left ventricular remodelling after implantation of Shelhigh SuperStentless aortic valve prostheses

AIM

Aortic valve replacement is a standard procedure for the treatment of severe aortic valve stenosis. Due to lower flow velocities stentless valves are associated with a more effective regression of left ventricular hypertrophy in comparison to stented valves. However, mismatch between body surface area and valve size supports unfavourable hemodynamic results. The aim of the study was to analyze hemodynamic parameters by echocardiography after implantation of the Shelhigh SuperStentless bioprosthesis and to analyze the occurrence of patient-prosthesis mismatch and left ventricular remodelling in this specific valve type.

METHODS

A total of 20 patients with severe aortic stenosis underwent implantation of a Shelhigh Super Stentless prosthesis. Clinical and echocardiographic assessment was done prior to, immediate after and six months after surgery.

RESULTS

All surgical procedures were successful, no surgery-related complication was documented perioperatively. One patient died after development of multiorgan failure. Echocardiography during the first eight days after surgery showed mean gradients of 16 mmHg, mean valve orifice areas of 1.8 cm(2) and indexed effective orifice areas at 0.95 cm(2)/m(2). Six-months follow-up data were obtained in 19/20 patients. There were no relevant changes in echocardiographic hemodynamic findings at the time of follow-up measurements. Significant regression of left ventricular hypertrophy was shown (P=0.0088). A patient-prosthesis mismatch occurred in one patient (0.54 cm(2)/m(2)). No recurrent symptoms were documented.

CONCLUSION

Patient-prosthesis mismatch after implantation of SuperStentless Shelhigh prosthesis is rare. A significant regression of left ventricular hypertrophy could be shown after six months. Hemodynamic valve function assessed by echocardiography may be predicted early after surgery.

Modified FOLFOX in combination with docetaxel for patients with metastatic adenocarcinoma of the stomach or gastroesophageal junction: A multicenter phase II study of the Arbeitsgemeinschaft Internistische Onkologie (AIO)

4545

Background: The combination of docetaxel, cisplatin, and fluorouracil (DCF) is clearly superior to CF in the treatment of patients (pts) with advanced gastric cancer (AGC). DCF is, however, associated with significant toxicity, including neutropenia, febrile neutropenia, diarrhea and mucositis. This study evaluated a biweekly, oxaliplatin-based modification of DCF. Methods: Pts with measurable, locally advanced or metastatic adenocarcinoma of the stomach or GE-junction and no prior chemotherapy received mFOLFOX (oxaliplatin 85 mg/sqm, leucovorin 200 mg/sqm, and fluorouracil 2.6 g/sqm via 24hr infusion) in combination with docetaxel 50 mg/sqm on day 1 every 2 weeks (FLOT-regimen). Prophylactic G-CSF was not administered. Overall response rate (RR) was the primary endpoint (power 80% to detect a RR of >40%) and toxicity profile the main secondary endpoint. The study was externally monitored according to GCP and data were reviewed by an independent safety board. Results: 59 pts (male, 41; female, 18) were enrolled. At the time of analysis, 53 pts were evaluable for toxicity and 51 pts for response. Median age was 60 (range, 29–76), median ECOG PS was 1, and almost all (93%) pts had metastatic disease. Of 51 pts, 2 had a CR and 25 pts attained a PR, adding to an overall RR of 53% (ITT-analysis). Stable disease was observed in 12 (23.5%) and progressive disease in 6 (11.8%) pts. Six (11.8%) pts were not evaluable for response. NCI-CTC grade 3 or 4 hematologic toxicity included leukopenia in 12 (22.6%), neutropenia in 23 (43%), and anemia in 2 (3.8%) pts. Febrile neutropenia was observed in 1 (1.9%) pt only. Other grade 3 or 4 toxicities included peripheral neuropathy in 4 (7.5%), nausea in 3 (5.7%), vomiting in 2 (3.8%) as well as diarrhea and fatigue in 5 (9.4%) pts each. No treatment related deaths were observed. Conclusions: FLOT is active and has a favorable toxicity profile in the treatment of pts with AGC. It may show activity also in perioperative treatment settings and may be considered as a useful treatment option for elderly pts. Survival data will be presented at the meeting.

[Table: see text]

Aortic valve replacement after previous coronary artery bypass grafting: experience with a simplified approach

AIM

Aortic valve replacement (AVR) after previous coronary artery bypass grafting (CABG), particularly in a patent left internal thoracic artery (ITA), is a challenge. Avoidance of injuring the patent graft and ensuring myocardial protection are important issues in the management of these patients. The aim of this study was to evaluate a simplified surgical approach to these reoperations.

METHODS

Between January 2003 and June 2005, 19 of 287 AVRs performed at our institution were in a patient subset (mean age 70 years, range: 62-82) who received AVR after previous CABG surgery. The aortic valve gradients were between 50 and 107 mm Hg. Our operation strategy followed the KIS-principle (keep it simple): both femoral vessels were cannulated using the Seldinger technique. Only the area around the ascending aorta and the right atrium was dissected to permit x-clamping, aortotomy, and catheterization for retrograde cardioplegia and a left ventricular vent. The anterior aspect of the heart and the left side, where the ITA was embedded and patent, were left untouched and not clamped.

RESULTS

The mean interval between the first and second operation was 6.5 years. Fourteen patients received biological prostheses. Four patients received an additional surgery at the time of AVR. The mean operating time was 267 min; the mean AoX-clamp time was 63 min. One patient died because of severe heart failure. In all others the postoperative course was uneventful.

CONCLUSIONS

We believe that the indication for AVR in patients scheduled for CABG should be re-evaluated. In those in which Redo-surgery for new or increased valve stenosis is indicated, a simple and safe surgical option is presented.

Biological activities of a recombinant adenovirus p53 (SCH 58500) administered by hepatic arterial infusion in a Phase 1 colorectal cancer trial

The major focus of intrahepatic arterial (IHA) administration of adenoviruses (Ad) has been on safety. Currently, there is little published data on the biological responses to Ad when administered via this route. As part of a Phase I study, we evaluated biological responses to a replication-defective adenovirus encoding the p53 transgene (SCH 58500) when administered by hepatic arterial infusion to patients with primarily colorectal cancer metastatic to the liver. In analyzing biological responses to the Ad vector, we found that both total and neutralizing Ad antibodies increased weeks after SCH 58500 infusion. The fold increase in antibody titers was not dependent on SCH 58500 dosage. The proinflammatory cytokine interleukin-6 (IL-6) transiently peaked within 6 h of dosing. The cytokine sTNF-R2 showed elevation by 24 h post-treatment, and fold increases were directly related to SCH 58500 doses. Cytokines TNF-alpha, IL-1beta, and sTNF-R1 showed no increased levels over 24 h. Predose antibody levels did not appear to predict transduction, nor did serum Ad neutralizing factor (SNF). Delivery of SCH 58500 to tumor tissue occurred, though we found distribution more predominantly in liver tissues, as opposed to tumors. RT-PCR showed significantly higher expression levels (P<0.0001, ANOVA) for adenovirus type 2 and 5 receptor (CAR) in liver tissues, suggesting a correlation with transduction. Evidence of tumor-specific apoptotic activity was provided by laser scanning cytometry, which determined a coincidence of elevated nuclear p53 protein expression with apoptosis in patient tissue. IHA administration of a replication defective adenovirus is a feasible mode of delivery, allowing for exogenous transfer of the p53 gene into target tissues, with evidence of functional p53. Limited and transient inflammatory responses to the drug occurred, but pre-existing immunity to Ad did not preclude SCH 58500 delivery.

[Value of arthroscopy in the treatment of upper ankle arthritis]

OBJECTIVE

The purpose of this retrospective study was to evaluate arthroscopy in upper ankle osteoarthritis.

METHODS

In the period from 1988 to 1997, 358 arthroscopies of the upper ankle joint were performed in 178 cases due to arthritis. Of 132 accessible patients, 124 replied to our questionnaire: 90 (73%) of the responders underwent clinical examination 94 (37-152) months following the initial arthroscopy and were graded according to the score of Evanski and Waugh. All arthroscopies were performed under fluid filling using anterolateral and anteromedial approaches. In only five cases was the posterior compartment additionally investigated. Generally, neither tourniquet nor mechanical joint distraction were applied.

RESULTS

Of a total of 12 (6.7%) complications, only 3 (1.7%) hematomas needed surgical revision. One hematoma was due to an arteriovenous fistula treated by double ligation. All complications including five hypesthesias were temporary and subsided spontaneously. The 124 patients of the questionnaire group assessed the result of arthroscopic surgery as excellent in 11%, good in 46%, fair in 22%, and poor in 21%. Of all patients, 22% required further surgery of the upper ankle: in 9% further arthroscopy, in 3% arthrodesis, and in 10% microsurgical denervation. The total range of motion increased from 10/0/40 degrees (extension/flexion) preoperatively to 15/0/44 degrees at the follow-up examination. The Evanski score improved significantly (p<0.001) from 41 to 76 points.

CONCLUSION

Due to minimal invasiveness and low risk of complications, arthroscopy is recommended for the following indications of upper ankle osteoarthritis: focal arthrosis, limited range of motion caused by osteophytes, soft tissue impingement, corpora libera, and synovitis. Severity and extent of upper ankle arthritis, range of motion, pain, local bone and soft tissue quality as well as the age, physical activity and compliance of the patient concerned are decisive for the individual therapeutic protocol. Alternative surgical techniques in upper ankle osteoarthritis are assessed such as denervation, distraction arthroplasty, correction osteotomy, ankle arthrodesis and total ankle replacement.

Interactions between selenium and sulphur nutrition in Arabidopsis thaliana

Selenium (Se) is an essential plant micronutrient, but is toxic at high tissue concentrations. It is chemically similar to sulphur (S), an essential plant macronutrient. The interactions between Se and S nutrition were investigated in the model plant Arabidopsis thaliana (L.) Heynh. Arabidopsis plants were grown on agar containing a complete mineral complement and various concentrations of selenate and sulphate. The Se/S concentration ratio in the shoot ([Se](shoot)/[S](shoot)) showed a complex dependence on the ratio of selenate to sulphate concentration in the agar ([Se](agar)/[S](agar)). Increasing [S](agar) increased shoot fresh weight (FW) and [S](shoot), but decreased [Se](shoot). Increasing [Se](agar) increased both [Se](shoot) and [S](shoot), but reduced shoot FW. The reduction in shoot FW in the presence of Se was linearly related to the shoot Se/S concentration ratio. These data suggest (i) that Se and S enter Arabidopsis through multiple transport pathways with contrasting sulphate/selenate selectivities, whose activities vary between plants of contrasting nutritional status, (ii) that rhizosphere sulphate inhibits selenate uptake, (iii) that rhizosphere selenate promotes sulphate uptake, possibly by preventing the reduction in the abundance and/or activity of sulphate transporters by sulphate and/or its metabolites, and (iv) that Se toxicity occurs because Se and S compete for a biochemical process, such as assimilation into amino acids of essential proteins.

The nacre protein perlucin nucleates growth of calcium carbonate crystals

Atomic force microscopy (AFM) in aqueous solution was used to investigate native nacre of the marine snail Haliotis laevigata on the microscopic scale and the interaction of purified nacre proteins with calcium carbonate crystals on the nanoscopic scale. These investigations were controlled by scanning electron microscopy (SEM), light microscopy (LM) and biochemical methods. For investigations with AFM and SEM, nacre was cleaved parallel to the aragonite tablets in this biogenic polymer/mineral composite. Multilamellar organic sheets consisting of a core of chitin with layers of proteins attached on both sides lay between the aragonite layers consisting of confluent aragonite tablets. Cleavage appeared to occur between the aragonite tablet layer and the protein layer. AFM images revealed a honeycomb-like structure to the organic material with a diameter of the 'honeycombs' equalling that of the aragonite tablets. The walls of the structures consisted of filaments, which were suggested to be collagen. The flat regions of the honeycomb-like structures exhibited a hole with a diameter of more than 100 nm. When incubated in saturated calcium carbonate solution, aragonite needles with perfect vertical orientation grew on the proteinacous surface. After treatment with proteinase K, no growth of orientated aragonite needles was detected. Direct AFM measurements on dissolving and growing calcite crystals revealed a surface structure with straight steps the number of which decreased with crystal growth. When the purified nacre protein perlucin was added to the growth solution (a super-saturated calcium carbonate solution) new layers were nucleated and the number of steps increased. Anion exchange chromatography of the water-soluble proteins revealed a mixture of about 10 different proteins. When this mixture was dialysed against saturated calcium carbonate solution and sodium chloride, calcium carbonate crystals precipitated together with perlucin leaving the other proteins in the supernatant. Thus perlucin was shown to be a protein able to nucleate calcium carbonate layers on calcite surfaces, and in the presence of sodium chloride, is incorporated as an intracrystalline protein into calcium carbonate crystals.

Simulation of the influence of sports surfaces on vertical ground reaction forces during landing

In many biomechanical analyses, the vertical ground reaction force (GRF) is measured by force plates. However, if force plates are fixed on elastic surfaces, the force signals have low-frequency oscillations superimposed. The question arises, as to whether this oscillation results from the response of the athlete to the surface properties or from the fixation of the force plate on the elastic surface. For the simulation of the vertical GRF, a mechanical model was developed that combines three submodels representing the surface, the athlete and the force plate. The simulations were carried out for landings on concrete and wooden elastic surfaces, without and with the force plate, respectively. Comparison of the two surfaces showed that, on the elastic surface, the passive peak of the vertical GRF was lower and was reached later than on the concrete surface. Thus a lower force rate was possible during the landing on the elastic surface (concrete: 186 body weight per second; wooden: 164 body weight per second), which can reduce the risk of damaging the joint cartilage. The simulations also showed that the time course of the GRF was changed by a rippling effect when the force plate was fixed on the elastic surface. The rippling was not the result of a change in the athlete's movements, because the parameters of the athlete submodel were not changed. The rippling induced by the force plate hinders the analysis of the GRF time course involving the real peak force and the force rate.

Characterization of the enzymatic component of the ADP-ribosyltransferase toxin CDTa from Clostridium difficile

Certain strains of Clostridium difficile produce the ADP-ribosyltransferase CDT, which is a binary actin ADP-ribosylating toxin. The toxin consists of the binding component CDTb, which mediates receptor binding and cellular uptake, and the enzyme component CDTa. Here we studied the enzyme component (CDTa) of the toxin using the binding component of Clostridium perfringens iota toxin (Ib), which is interchangeable with CDTb as a transport component. Ib was used because CDTb was not expressed as a recombinant protein in Escherichia coli. Similar to iota toxin, CDTa ADP-ribosylates nonmuscle and skeletal muscle actin. The N-terminal part of CDTa (CDTa1-240) competes with full-length CDTa for binding to the iota toxin binding component. The C-terminal part (CDTa244-263) harbors the enzyme activity but was much less active than the full-length CDTa. Changes of Glu428 and Glu430 to glutamine, Ser388 to alanine, and Arg345 to lysine blocked ADP-ribosyltransferase activity. Comparison of CDTa with C. perfringens iota toxin and Clostridium botulinum C2 toxin revealed full enzyme activity of the fragment Ia208-413 but loss of activity of several N-terminally deleted C2I proteins including C2I103-431, C2I190-431, and C2I30-431. The data indicate that CDTa belongs to the iota toxin subfamily of binary actin ADP-ribosylating toxins with respect to interaction with the binding component and substrate specificity. It shares typical conserved amino acid residues with iota toxin and C2 toxin that are suggested to be involved in NAD-binding and/or catalytic activity. The enzyme components of CDT, iota toxin, and C2 toxin differ with respect to the minimal structural requirement for full enzyme activity.

HER-2/neu overexpression and in vitro chemosensitivity to CMF and FEC in primary breast cancer

Available clinical and experimental data on the effect of HER-2/neu overexpression on chemosensitivity are controversial. It was the purpose of this in vitro study to define the association between HER-2/neu overexpression and the sensitivity to the chemotherapeutic drug combinations of cyclophosphamide, methotrexate and 5-fluorouracil (CMF) and 5-fluorouracil, epirubicin and cyclophosphamide (FEC) of breast cancer cells derived from 140 chemotherapy-naïve patients at the time of primary surgery. Both drug combinations were tested at six different concentrations ranging from 6.25-200% peak plasma concentration (PPC). Immunohistochemical detection of HER-2/neu overexpression was performed with the HER-2/neu antibodies, CB11, TAB250 and AO485, in the same tumor specimens. Immunoreactions were determined as negative (0/1+), weakly positive (2+) and strongly positive (3+). However, the antibodies varied in their degrees of sensitivity. Breast cancer samples with strong (3+) HER-2/neu overexpression demonstrated 90% growth inhibition (IC90) at significantly lower PPC values, using the CB11 (p = 0.048), TAB250 (p = 0.007) and AO485 (p < or =0.01) antibodies, and showed 50% growth inhibition (IC50) at significantly lower PPC values, using the CB11 antibody (p = 0.01) compared to their counterparts with lower levels of HER-2/neu expression. When analyzing the group of patients with intermediate and strong HER-2/neu overexpression (2+ and 3+), an association between HER-2/neu overexpression and increased chemosensitivity was seen with the TAB250 (p = 0.044) and AO485 (p = 0.032) antibodies, but not with the CB11 antibody (p =0.8) at the IC90 level. Differences in chemosensitivity between samples with strong HER-2/neu overexpression and those with lower levels were then analyzed separately for CMF and FEC. Both regimens achieved 90% tumor growth inhibition at lower PPC values in samples with strong HER-2/neu overexpression (3+) compared to their counterparts with lower expression levels (AO485 p = 0.011 for CMF, and p = 0.09 for FEC). Cumulative concentration-response plots of tumors responding in vitro with 90% tumor cell inhibition showed a stronger dose dependence for both CMF and FEC among tumor samples with strong HER-2/neu overexpression compared to those with lower levels of expression. In conclusion, the data show that HER-2/neu overexpression was not associated with in vitro drug resistance to CMF or FEC. In contrast, tumors with strong HER-2/neu overexpression demonstrated increased dose-dependent in vitro sensitivity to both the FEC and CMF regimens.

Simulating the impact during human jumping by means of a 4-degrees-of-freedom model with time-dependent properties

The authors simulated the vertical movements of a jumper and the force time courses by means of a 4-degrees-of-freedom model consisting of 4 masses, springs, and dampers. Of the motions simulated, only that of the mass imitating the trunk corresponded to the measured data. The best fit to the measured force curves were obtained in the simulation in which time-dependent model parameters were used. From the results, the authors concluded that at the beginning of the landing, a jumper behaves like a 2-mass model in which the leg segments (thighs, shanks, and feet) effectively combine into 1 mass. After approximately 60 ms, the connections between the leg segments become more compliant and the jumper behaves like a 4-mass model with a soft coupling between the leg segments. The process is equivalent to an increase of the degrees of freedom of the movements. At the end of the ground contact phase during hopping, the jumper has to contract the muscles in order to reach the envisaged jump height. In the model, that contraction could not be satisfactorily simulated.