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A non-immune library of human single chain fragment variable (scFv) antibodies displayed on Sacchar- omyces cerevisiae was screened for binding to the Clostridium botulinum neurotoxin serotype A binding domain (BoNT/A (Hc)) with the goal of identifying scFv to novel epitopes. To do this, an antibody-mediated labeling strategy was used in which antigen-binding yeast clones were selected after label- ing with previously characterized monoclonal antibodies (MAbs) specific to the Hc. Twenty unique scFv clones were isolated that bound Hc. Of these, 3 also bound to full-length BoNT/A toxin complex with affinities ranging from 5 to 48 nM. Epitope binning showed that the three unique clones recognized at least two epitopes distinct from one another as well as from the detection MAbs. After production in E. coli, scFv were coupled to magnetic particles and tested for their ability to capture BoNT/A holotoxin using an Endopep-MS assay. In this assay, toxin captured by scFv coated magnetic particles was detected by incubation of the complex with a peptide containing a BoNT/A-specific cleavage sequence. Mass spectrometry was used to detect the ratio of intact peptide to cleavage products as evidence for toxin capture. When tested individually, each of the scFv showed a weak positive Endopep-MS result. However, when the particles were coated with all three scFv simultaneously, they exhib- ited significantly higher Endopep-MS activity, consistent with synergistic binding. These results demonstrate novel approaches toward the isolation and characterization of scFv antibodies specific to unlabeled antigens. They also provide evidence that distinct scFv antibodies can work synergisti- cally to increase the efficiency of antigen capture onto a solid support. Biotechnol. Bioeng. 2011;108: 2456-2467.

Two new synthetic melanin-like oligomers inspired by the synthesis of pheomelanin (cys-DOPA) were prepared using L-DOPA as a precursor and the amino acids serine (ser-DOPA) and threonine (thr-DOPA) for modifications. The products obtained exhibited appreciable antioxidant activity. The compounds were characterized by liquid chromatography-mass spectrometry (LC-MS), elemental analysis and infrared spectroscopy. The pKa values of the groups present in each melanin suspension were determined in aqueous solution by potentiometric and spectrophotometric titration. Cytotoxicity assays showed an IC50 > 500 mg L -1 resulting in non-toxic compounds for living cells. Finally, cys-DOPA, ser-DOPA and thr-DOPA exhibited antioxidant activity determined by the DPPH scavenging assay, with EC50 = 7.69, 1.02 and 27.60 mg L -1 , respectively.

Yeast display is a powerful tool for increasing the affinity and thermal stability of scFv antibodies through directed evolution. Mammalian calmodulin (CaM) is a highly conserved signaling protein that undergoes structural changes upon Ca 2 + binding. In an attempt to generate conformation-specific antibodies for proteomic applications, a selection against CaM was undertaken. Flow cytometry-based screening strategies to isolate easily scFv recognizing CaM in either the Ca 2 + -bound (Ca 2 + -CaM) or Ca 2 + -free (apo-CaM) states are presented. Both full-length scFv and single-domain VH only clones were isolated. One scFv clone having very high affinity (K d = 0.8 nM) and specificity (>1000-fold) for Ca 2 + -CaM was obtained from de novo selections. Subsequent directed evolution allowed the development of antibodies with higher affinity (K d = 1 nM) and specificity (>300-fold) for apo-CaM from a parental single-domain clone with both a modest affinity and specificity for that particular isoform. CaM-binding activity was unexpectedly lost upon conversion of both conformation-specific clones into soluble fragments. However, these results demonstrate that conformation-specific antibodies can be quickly and easily isolated by directed evolution using the yeast display platform.

In a free-electron laser (FEL) the lasing medium is a high-energy beam of electrons flying with relativistic speed through a periodic magnetic field. The interaction between the synchrotron radiation that is produced and the electrons in the beam induces a periodic bunching of the electrons, greatly increasing the intensity of radiation produced at a particular wavelength. Depending only on a phase match between the electron energy and the magnetic period, the wavelength of the FEL radiation can be continuously tuned within a wide spectral range. The FEL concept can be adapted to produce radiation wavelengths from millimetres to Angstroms, and can in principle produce hard x-ray beams with unprecedented peak brightness, exceeding that of the brightest synchrotron source by ten orders of magnitude or more. This paper focuses on short-wavelength FELs. It reviews the physics and characteristic properties of single-pass FELs, as well as current technical developments aiming for fully coherent x-ray radiation pulses with pulse durations in the 100 fs to 100 as range. First experimental results at wavelengths around 100 nm and examples of scientific applications planned on the new, emerging x-ray FEL facilities are presented.

Gigawatt level radiation pulses at wavelengths between 80 and 120 nm and a pulse duration below 100 fs have recently been produced by a single-pass free electron laser at DESY. The radiation has been characterized with respect to pulse energy, statistical properties, spectral distribution and coherence. It has also been used for first experiments on solids and gases demonstrating the potential of the new source. The facility is currently upgraded to higher energy and is planned to start user operation in 2004. Based on this work a large free electron laser laboratory with several experimental stations for the hard X-ray regime down to 1 A will be built at DESY which could start user operation at the beginning of the next decade.

A nonimmune library of 10(9) human antibody scFv fragments has been cloned and expressed on the surface of yeast, and nanomolar-affinity scFvs routinely obtained by magnetic bead screening and flow-cytometric sorting. The yeast library can be amplified 10(10)-fold without measurable loss of clonal diversity, allowing its effectively indefinite expansion. The expression, stability, and antigen-binding properties of >50 isolated scFv clones were assessed directly on the yeast cell surface by immunofluorescent labeling and flow cytometry, obviating separate subcloning, expression, and purification steps and thereby expediting the isolation of novel affinity reagents. The ability to use multiplex library screening demonstrates the usefulness of this approach for high-throughput antibody isolation for proteomics applications.

Crossover femorofemoral bypass graft (CFFBG) was proposed in the early days of modern vascular surgery to treat patients affected with unilateral iliac artery disease who were a high surgical risk. We investigated factors influencing short- and long-term outcomes of CFFBG:The study was designed as a retrospective clinical study in a university hospital setting with a base of 228 patients. Of these patients, 154 (67.5%) presented a high surgical risk. The indication for operation was limb-threatening ischemia in 188 (82.5%) patients. All patients underwent CFFBG: The procedure was performed in 150 patients as the primary operation and in 78 patients after previous vascular graft failure or infection, or both. A preoperative percutaneous transluminal angioplasty was performed in 57 patients (25%) to correct donor iliac artery disease. In 127 patients (55.7%), an associated vascular procedure was performed to improve the outflow. Postoperative complications; 5- and 10-year primary, secondary, and limb salvage rates; and factors influencing short- and long-term results were assessed.Thirteen (5.7%) postoperative deaths occurred. Postoperative mortality and morbidity rates were significantly higher in patients aged more than 65 years (7.9% versus 3.5% and 18.6% versus 6.1%, respectively, P.03). Primary and secondary patency rates at 5 and 10 years were 70.2% and 48.1%, 82.8% and 63.2%, respectively; 5- and 10-year limb salvage and survival rates were 85.5% and 80.1%, 63.3% and 31.0%, respectively. Ten-year primary and secondary patency and limb salvage rates were significantly lower when the procedure was performed after previous vascular graft failures (50.2% versus 26.5%, P.007; 74.1% versus 44.1%, P.01; and 84.3% versus 72.5%, P.03, respectively). Five- and 8-year patency rates of autogenous vein CFFBG (34.3% and 22.8%, respectively, P.03) were significantly lower than those of expanded polytetrafluoroethylene (71.1% and 59.8%, respectively) and polyester (77.3% and 50.3%, respectively) CFFBG: Moreover, 5- and 10-year primary and secondary patency rates were significantly better when externally supported grafts were used as compared with those without external support (80.1% and 69.9% versus 61.1% and 21.1%, P.01; 88.8% and 75.9% versus 78.9% and 45.4%, P.05, respectively). Multivariate analysis showed that the only variable associated with poor primary and secondary patency and limb salvage rates was the operation performed after previous vascular graft failures (P.04, P.03 and P.05, respectively).CFFBG allows early and long-term results similar to those obtained with reconstructions originating from the aorta when it is performed as a primary operation when an adequate outflow is provided and externally supported prosthetic material is used.

Purpose: The aim of the study was to investigate surgical indication and long-term outcome of carotid endarterectomy (CE) in young adults.Methods: Between 1973 and 1990, 1693 patients underwent CE. Forty-nine patients (group 1) 35 to 45 years of age who had carotid artery stenosis greater than 70%, formed the basis for the analysis. They were compared with two additional groups of patients older than 45 years of age selected from the entire series. Group 2 was randomly chosen to determine differences in risk factors, associated diseases, operative indications, preoperative findings, and outcome. Group 3 was matched with patients in group 1 for sex, risk factors, associated diseases, preoperative findings, and operative indications to assess the importance of age in determining the short- and long-term outcome of CE.Results: Postoperative mortality, cerebrovascular accidents, and cardiac complications in patients of group 1 (2%, 2%, and 2%, respectively) were similar to those of the other groups ( p = NS). During the follow-up (76.7 ± 3.6 months; range, 1 to 120 months) the incidence of strokes and transient ischemic attacks in group 1 was lower than in group 2 ( p < 0.05) but similar to group 3 ( p = NS). Ten-year disease-free intervals were 75.7%, 58.7%, and 77.6%, respectively, for groups 1, 2, and 3. Mortality rate unrelated to cerebrovascular disease was similar between group 1 and group 3 ( p = NS) but was higher in group 1 than in group 2 ( p < 0.02). Ten-year survival rates were 46.1%, 71.7%, and 55.5%, respectively, for group 1, 2, and 3.Conclusions: CE in patients younger than 45 years of age is a safe procedure with low operative risks and good disease-free intervals. However, life expectancy is poor because of the high incidence of deaths resulting from complications of atherosclerosis.(J Vasc Surg 1997;25:464-70.)

Recurrence or persistence of neurologic symptoms after surgical treatment of patients with thoracic outlet syndrome (TOS) are reported to be as high as 25%. To identify factors affecting the long-term outcome of surgical treatment of patients with TOS, we reviewed our 20-year experience.One hundred thirty-four transaxillary first rib resections were performed on 118 patients (43 men, 75 women, mean age 38 +/- 13 years). Eighty-three operations (61.9%) were undertaken to relieve symptoms resulting from compression of the lower roots of the brachial plexus, 37 (27.6%) for compression of both lower and upper roots, and 14 (10.5%) for lower root and vascular symptoms. All patients underwent a transaxillary extraperiosteal first rib resection with transection of the scalene muscles. In 73 cases (54.5%) a resection of the anterior scalene muscle was also performed. A cervical rib was removed in 28 cases (20.1%), and anomalous fibrous bands adjacent to the neurovascular bundle were resected in 41 cases (30.6%).No major complications were observed. Of 105 patients (118 procedures) followed up (mean follow-up, 99 +/- 72 months), good to excellent results were obtained in 96 cases (81.4%) and fair to poor results were recorded in 22 cases (18.6%). The presence of a long posterior first rib stump, measured from the chest x ray films, was the strongest determinant of the long-term results among the variables examined (p0.0001). Reoperation, consisting of neurolysis and resection of the stump, was performed in 16 patients. The results were excellent in all cases at a mean follow-up of 66 +/- 46 months. Primary and secondary 10-year, actuarial freedom rates from recurrent symptoms were 80.9% and 93.1%, respectively.Our results suggest that the long-term outcome after surgery for TOS was strongly influenced by the extent of the first rib resection.

A substantial enhancement of intensity in the high-energy part of the ${\mathrm{N}}_{2}$ KLL Auger spectrum has been observed at photon energies a few tens of eV above the N 1s threshold. By monitoring the corresponding 1s photoelectron spectrum, we show that the effect is due to the emergence of strong conjugate shake-up satellites. As shown in previous e-2e studies for CO, such Auger spectra are useful in determining the intensity behavior of shake-up satellites in the immediate threshold regions.

FLASH has been a user facility since 2005, delivering radiation in the wavelength range between 7 and 47 nm using the SASE principle. After the present upgrade, the wavelength range is extended to 4.45 nm. With the third harmonic accelerating module in place to linearize the longitudinal phase space, the stability and reproducibility of the machine is substantially improved. The user requests for beam time by far exceeds the time available. In order to increase user beam time and to improve the radiation properties delivered to users, a major extension of the user facility called FLASH II has been proposed by DESY in collaboration with the HZB. FLASH II is a seeded FEL in the parameter range of FLASH. As logical continuation, the seeding with HHG which started with sFLASH will result in direct seeding. Because in the foreseeable future there will probably not be HHG seed lasers available at high repetition rates down to wavelengths of 4 nm, a cascaded HGHG scheme is proposed to produce short wavelengths. After a first design report, the project now enters its technical design phase. During this time, the FLASH beam parameters after the present upgrade 2009/2010 will be characterized and the present design will be re-evaluated and adjusted. In addition, start-to-end simulations will complete the simulations which have been performed so far, including a design of the extraction area.

From April, 1990, to April, 1992, peripheral atherectomy using a Simpson AtheroCath was performed in 46 patients (56 limbs) with a total of 106 lesions. There were 100 stenoses (74 eccentric, 26 concentric) and 6 occlusions. Success was achieved in 103/106 (97%) procedures (97 stenoses and 6 occlusions), reducing the lesion to < 35% (stenoses: 81±13% to 22±9%, p < 0.0001, and the occlusions : 100% to 16±8%; p < 0.0001). Ankle/brachial index (ABI) improved from 0.58±0.17 to 0.85 ± 0.22 (p < 0.0001). Clinical success was achieved in 42 patients (91%). Complications occurred in 6 patients (13%): groin hematoma in 5, and in 1, acute occlusion of the femoral artery with distal embolization. There were 13 hemodynamic failures in 11 patients (28%) with an ABI reduction of more than 0.15 with respect to the maximum early postoperative level, over a mean follow-up of 15.1 months. Failure of the procedure was confirmed by arteriography in only 4 cases. Cumulative eighteen-month patency rates were 60% using arteriographic assessment and 44% for hemodynamic assessment (p < 0.025). Patency rates were 56% for the patients with a runoff score ranging between 1 and 5 and 17% with a score > 5 (p < 0.0025). A reduction of ABI during follow-up is not a true indicator of procedural failure, but it correlates with possible progression of distal disease. Evaluation of preoperative runoff may be used as a prognostic indicator.

FLASH (free electron laser in Hamburg) is a unique, ultra-brilliant soft x-ray source providing highly coherent femtosecond pulses, currently in a wavelength range of 6.8–47 nm. Up to several 1012 coherent photons within a 10–70 fs pulse allow the study of dynamical changes in nanometer-sized structures. This is a big step towards the ultimate goal of observing femtosecond dynamics on the atomic length scale, for example 'watching bio-machines at work'. In this review, the properties of FLASH are summarized with a focus on coherence, and the potential of FLASH for structural investigations is illustrated with an overview of the recently performed coherent imaging experiments.

Using a noninvasive, electro-optically based electron bunch arrival time measurement at FLASH (free electron laser in Hamburg) the temporal resolution of two-color pump-probe experiments has been significantly improved. The system determines the relative arrival time of the extended ultraviolet pulse of FLASH and an amplified Ti:sapphire femtosecond-laser pulse at the interaction region better than 90 fs rms. In a benchmarking pump-probe experiment using two-color above threshold ionization of noble gases, an enhancement in the timing resolution by a factor of 4 compared to the uncorrected data is obtained.

Leiomyosarcoma of the inferior vena cava is a rare and potentially curable tumor. Uncertainty about the results of treatment derives from lack of a large series in the same center and of a long-term follow-up of the published cases. A review of the world literature from 1871 to 1989 allowed us to collect information on 141 patients with inferior vena cava leiomyosarcoma to which our three cases have to be added. The tumor arose from the lower segment of the inferior vena cava (infrarenal portion) in 49 patients, from the middle segment (from the renal veins to the hepatic veins) in 59, and from the upper segment (from the hepatic veins to the right atrium) in 34 patients. Complete clinical, pathologic, and therapeutic data and up-to-date follow-up have been obtained through personal correspondence with several authors. All data have been examined with both univariate and multivariate analyses as predictive factors for outcome. Variables, associated with an increased risk of death from disease, included the involvement of inferior vena cava upper segment and a high-grade tumor. Patients who underwent a radical resection of the tumor (82 patients, 56.9%) had a significantly better survival (27.9% and 14.2%, 5- and 10-year survival rates, respectively). Of these patients, those with tumor of the inferior vena cava middle segment fared better than those with lower segment tumor (5- and 10-year survival rates were 48.3% and 34.4%, respectively, for middle segment tumor and 9.3% and 0.0% for lower segment tumor). Variables associated with a good outcome and longer survival were the presence of abdominal pain and the absence of a palpable abdominal mass. Despite the high rate of recurrence (52.4% of patients undergoing radical operation; median time, 25 months), radical resection of inferior vena cava leiomyosarcoma is the only chance for a long-term cure. An earlier and more accurate preoperative diagnosis, by means of modern diagnostic techniques (echography, CT scanning, magnetic resonance imaging) will allow a higher rate of radical resection to be performed with an increase in patient survival.

We have constructed transcriptional fusion vectors for use in Bacteroides spp., a genus of gram-negative obligate anaerobes found in high numbers in the human colon. The reporter group in these vectors is a promoterless beta-glucuronidase gene from Escherichia coli (uidA). Two of the vectors (pMJF-2 and pMJF-3) replicate in Bacteroides spp. The third, pCQW-1, does not replicate in Bacteroides spp. and can be used to introduce E. coli beta-glucuroindase fusions into the Bacteroides chromosome.

Two-color multiphoton ionization of atomic helium was investigated by combining extreme ultraviolet (XUV) radiation from the Free Electron Laser in Hamburg with an intense synchronized optical laser. In the photoelectron spectrum, lines associated with direct ionization and above-threshold ionization show strong variations of their amplitudes as a function of both the intensity of the optical dressing field and the relative orientation of the linear polarization vectors of the two fields. The polarization dependence provides direct insight into the symmetry of the outgoing electrons in above-threshold ionization. In the high field regime, the monochromaticity of the XUV radiation enables the unperturbed observation of nonlinear processes in the optical field.

Sealed rupture of abdominal aortic aneurysms, even if uncommon, deserves particular attention for the possibility of misdiagnosis and for the deleterious effects of such a misdiagnosis. Sixteen patients (mean age 72 years; range 65 to 84 years) with chronic sealed rupture of abdominal aortic aneurysms are reported. Two patients had acute rupture of the aneurysm, and at operation chronic contained rupture was found along with the recent hemorrhage. One patient died after surgery. The remaining patients underwent successful resection with long-term survival and regression of symptoms. Consideration of sealed abdominal aortic aneurysm rupture should be included when examining elderly patients with history of unexplained back pain or femoral neuropathy. Computed tomography is a useful aid in the diagnosis of sealed rupture. Ultrasonography is less accurate; in three patients ultrasonography failed to diagnose the presence of the rupture. (J VASC SURG 1990;11:430-5.)

Two-color above threshold ionization of helium and xenon has been used to analyze the synchronization between individual pulses of the femtosecond extreme ultraviolet (XUV) free electron laser in Hamburg and an independent intense 120 fs mode-locked Ti:sapphire laser. Characteristic sidebands appear in the photoelectron spectra when the two pulses overlap spatially and temporally. The cross-correlation curve points to a 250 fs rms jitter between the two sources at the experiment. A more precise determination of the temporal fluctuation between the XUV and infrared pulses is obtained through the analysis of the single-shot sideband intensities.

We describe an experimental system designed for single-shot photoelectron spectroscopy on free atoms and molecules at the Free Electron Laser in Hamburg (FLASH at DESY). The combination of the extreme ultra-violet (EUV) Free Electron Laser and a temporally synchronized optical fs laser (Ti:Sapphire) enables a variety of two-color pump-probe experiments. The spectral, temporal and spatial characteristics of both the EUV FEL and the optical laser pulses, the experimental procedure to control their overlap as well as the performance of an electron spectrometer used to obtain single-shot photoelectron spectra are discussed. As an illustration of the capabilities of this set-up, some results on two-photon two-color ionization of rare gases are presented.

Two-photon ionization of atomic helium has been measured by combining femtosecond extreme-ultraviolet pulses from the free-electron laser in Hamburg (FLASH at DESY) with intense light pulses from a synchronized neodymium-doped yttrium lithium fluoride laser. Sidebands appear in the photoelectron spectra when the two laser pulses overlap in both space and time. Their intensity exhibits a characteristic dependence on the relative time delay between the ionizing and the dressing pulses and provides an inherent time marker for time-resolved pump-probe experiments. The measurements of the sidebands are in good agreement with theoretical predictions and allow for a direct analysis of two-photon ionization, free from processes related to interference between multiple quantum paths.

Intense radiation from lasers has opened up many new areas of research in physics and chemistry, and has revolutionized optical technology. So far, most work in the field of nonlinear processes has been restricted to infrared, visible and ultraviolet light, although progress in the development of X-ray lasers has been made recently. With the advent of a free-electron laser in the soft-X-ray regime below 100 nm wavelength, a new light source is now available for experiments with intense, short-wavelength radiation that could be used to obtain deeper insights into the structure of matter. Other free-electron sources with even shorter wavelengths are planned for the future. Here we present initial results from a study of the interaction of soft X-ray radiation, generated by a free-electron laser, with Xe atoms and clusters. We find that, whereas Xe atoms become only singly ionized by the absorption of single photons, absorption in clusters is strongly enhanced. On average, each atom in large clusters absorbs up to 400 eV, corresponding to 30 photons. We suggest that the clusters are heated up and electrons are emitted after acquiring sufficient energy. The clusters finally disintegrate completely by Coulomb explosion.

In this paper, we describe optical feedback system of VUV Regenerative FEL Amplifier (RAFEL) at the TESLA test facility at DESY. The aim of the RAFEL experiment is to construct fully coherent, tunable VUV radiation source by means of applying narrow-band optical feedback in the VUV SASE FEL operating currently at DESY. One of the problem of the realization of the RAFEL is severe requirements for the angular stability of the optical elements (about few microradians). This problem has been solved by means of installation of active alignment system with reference laser. Another problem is alignment of optical elements separated by 65 m within complicated experimental conditions connected with aperture limitations (down to 6 mm ) . This problem has been solved in two steps. Preliminary alignment with an accuracy of about 80 μrad has been performed with laser alignment system and OTR screens used at the TTF accelerator for electron beam diagnostics. Final alignment has been performed with VUV SASE FEL radiation. Measured feedback coefficient is about 1 percent and is in agreement with the designed value.

Ceramide levels increase in activated polymorphonuclear neutrophils, and here we show that endogenous ceramide induced degranulation and superoxide generation and increased surface beta(2)-integrin expression. Ceramide accumulation reveals a bifurcation in integrin function, as it abolished agonist-induced adhesion to planar surfaces, yet had little effect on homotypic aggregation. We increased cellular ceramide content by treating polymorphonuclear neutrophils with sphingomyelinase C and controlled for loss of sphingomyelin by pretreatment with sphingomyelinase D to generate ceramide phosphate, which is not a substrate for sphingomyelinase C. Pretreatment with the latter enzyme blocked all the effects of sphingomyelinase C. Ceramide generation caused a Ca(2+) flux and complete degranulation of both primary and secondary granules and increased surface beta(2)-integrin expression. These integrins were in a nonfunctional state, and subsequent activation with platelet-activating factor or formyl-methionyl-leucyl-phenylalanine induced beta(2)-integrin-dependent homotypic aggregation. However, these cells were completely unable to adhere to surfaces via beta(2)-integrins. This was not due to a defect in the integrins themselves because the active conformation could be achieved by cation switching. Rather, ceramide affected cytoskeletal organization and inside-out signaling, leading to affinity maturation. Cytochalasin D induced the same disparity between aggregation and surface adhesion. We conclude that ceramide affects F-actin rearrangement, leading to massive degranulation, and reveals differences in beta(2)-integrin-mediated adhesive events.

The absolute photoabsorption cross section of benzene (C6H6), encompassing the C 1s-1 π*e2u resonance, the C 1s threshold, the satellite thresholds, and extending up to 800 eV, has been measured using synchrotron radiation. Measurements of the discrete absorption structure from below the C 1s ionization threshold have been performed at high resolution. In order to unambiguously assign all structure present in the photoabsorption cross section, C 1s photoelectron spectra were measured from the C 1s threshold region up to 350 eV along with satellite spectra. The C1s-1 single-hole and the satellite cross sections have been derived in absolute units, and their angular distributions have been determined. Resonant and normal Auger spectra were taken on the main features of the photoabsorption and single-hole cross sections. From the best resolved photoelectron spectra the underlying structure in the asymmetric benzene photoelectron peak can be partly disentangled. The experimental data show that at least two vibrational modes play a role in the C 1s photoelectron spectrum. The behavior of the investigated shake-up structure closely resembles that of ethene and ethyne, where the satellite bands due to π→π* excitations gain intensity towards threshold, an observation which may be attributed to conjugate shake-up processes. These processes lead to a significant contribution of the satellite intensity to the production of the absorption features traditionally assigned to the carbon shape resonances in benzene. An EXAFS analysis of the wide range oscillations present on the photoabsorption cross section has been performed, and reveals the C–C nearest-neighbor distance.

We present the first observation of Self-Amplified Spontaneous Emission (SASE) in a free-electron laser (FEL) in the Vacuum Ultraviolet regime at 109 nm wavelength (11 eV). The observed free-electron laser gain (approx. 3000) and the radiation characteristics, such as dependency on bunch charge, angular distribution, spectral width and intensity fluctuations all corroborate the existing models for SASE FELs., 6 pages including 6 figures; e-mail: joerg.rossbach@desy.de

Oncostatin M is a member of the IL-6 family of cytokines that is primarily known for its effects on cell growth. Endothelial cells have an abundance of receptors for oncostatin M, and may be its primary target. We determined if oncostatin M induces a key endothelial cell function, initiation of the inflammatory response. We found that subcutaneous injection of oncostatin M in mice caused an acute inflammatory reaction. Oncostatin M in vitro stimulated: (a) polymorphonuclear leukocyte (PMN) transmigration through confluent monolayers of primary human endothelial cells; (b) biphasic PMN adhesion through rapid P-selectin expression, and delayed adhesion mediated by E-selectin synthesis; (c) intercellular adhesion molecule-1 and vascular cell adhesion molecule-1 accumulation; and (d) the expression of PMN activators IL-6, epithelial neutrophil activating peptide-78, growth-related cytokine alpha and growth-related cytokine beta without concomitant IL-8 synthesis. The nature of the response to oncostatin M varied with concentration, suggesting high and low affinity oncostatin M receptors independently stimulated specific responses. Immunohistochemistry showed that macrophage-like cells infiltrating human aortic aneurysms expressed oncostatin M, so it is present during a chronic inflammatory reaction. Therefore, oncostatin M, but not other IL-6 family members, fulfills Koch's postulates as an inflammatory mediator. Since its effects on endothelial cells differ significantly from established mediators like TNFalpha, it may uniquely contribute to the inflammatory cycle.

19th International Conference on Free Electron Lasers, FEL'97, Beijing, China, 18 Aug 1997 - 21 Aug 1997; TESLA-FEL Reports 36-39 (1997).

Round-tipped blunt needle (BN) may decrease the risk of needlestick injuries and hand contamination. We prospectively determined the incidence of glove perforations in emergency abdominal procedures and the efficacy of BN in increasing the safety for surgeons.Two hundred patients were randomized to undergo closure of the abdominal fascia using sharp needle (SN) or BN. Gloves were tested at the end of the procedure.Surgeons had 14 needlestick injuries and 76 perforations recorded in 69 pair of gloves. Sharp needles were responsible for all injuries and 58 (76%) perforations (P0.00004 and P0.00001, respectively). This difference was still higher when considering the perforations related to the abdominal fascia closure (BN 7% versus SN 50%; P0.0006).The risk of glove perforation is sevenfold greater if SN are used. Blunt needles reduce sharp injuries and improve safety for surgeons.

The C 1s partial photoionization cross section and photoelectron angular distribution of methane (${\mathrm{CH}}_{4}$) have been measured with high-energy resolution between threshold and 385 eV photon energy. From the analysis of the vibrational fine structure on the C 1${\mathit{s}}^{\mathrm{\ensuremath{-}}1}$ photoelectron line a vibrational energy of 396\ifmmode\pm\else\textpm\fi{}2 meV and an equilibrium bond length of 1.039(\ifmmode\pm\else\textpm\fi{}0.001) \AA{} for the ${\mathrm{CH}}_{4}^{+}$ ion have been determined. The lifetime broadening was found to be 83(\ifmmode\pm\else\textpm\fi{}10) meV. The weak feature in the photoabsorption cross section just above threshold does not influence the vibrational fine structure in a way typical for a shape resonance. We therefore suggest that it is due to doubly excited states of the type C (1s${)}^{\mathrm{\ensuremath{-}}1}$(Val${)}^{\mathrm{\ensuremath{-}}1}$(Ryd${)}_{\mathit{a}}^{1}$(Ryd${)}_{\mathit{b}}^{1}$, an assignment which is supported by recent Auger decay studies. Measurements of the shakeup structure revealed six satellite lines, one of which increases strongly in intensity at threshold, thus pointing to the existence of a conjugate shakeup process. \textcopyright{} 1996 The American Physical Society.

Core hole decay spectra of the free N{sub 2} molecule show evidence for hitherto unobserved molecular resonances both below and above the {ital K}-shell photoionization threshold. Based on earlier calculations they are assigned to doubly excited neutral states which could not be seen below threshold in recent high resolution absorption spectra because of the more intense core-to-Rydberg excitations. By calculating the Auger spectrum of core-excited nitrogen atoms, we show that the features are atomiclike. {copyright} {ital 1996 The American Physical Society.}

Synthetic grafts are widely used for peripheral arterial reconstructions when autologous veins are not available, but their results have not been satisfactory. Venous allograft may be used as an alternative to synthetic prostheses. The aim of the study was to explore the immunosuppressive efficacy of Cyclosporine A (CyA) as a means of preventing venous allograft failures and rejection. We utilized 56 mongrel dogs. Immunological incompatibility was checked with the skin graft method. Donor inferior vena cava was transplanted into the infrarenal abdominal aorta of recipient animals. One group (group 1, 10 dogs) served as a control and three groups received CyA treatment regimens. Group 2 (10 dogs) received postoperative oral CyA treatment for 30 days. Group 3 (12 dogs) received a vein graft pretreated with a CyA solution without postoperative immunosuppressive therapy. Group 4 (9 dogs) received a vein graft pretreated with a CyA solution and postoperative CyA treatment for 30 days. Allografts were examined at 30 days for patency, aneurysmal dilatation, gross structural changes, inflammatory response, and lymphocytic infiltration. Sex chromatine assessment determined the origin (donor or recipient) of the endothelial cells. The allografts from groups 1 and 3 showed significant aneurysmal dilatation and perivenous inflammation when compared to dogs treated with oral CyA therapy (P0.0002). Moreover allografts treated with CyA therapy had a better-developed venous neointima (P0.009) with less fibrin (P0.02) and thinner medial (P0.0009) with less fibrin (P0.02), and thinner medial (P0.0009) and adventitial layers (P0.02). No significant differences were observed in neointimal thickness among the four groups. Lymphocytic infiltration was greater in the group of animals who did not receive oral CyA therapy (P0.0004). Barr bodies status showed significant differences between oral CyA treated groups and nontreated groups (P0.0003). Oral CyA therapy reduced aneurysmal dilatation and immunological response, promoted the development of a neoendothelium, and preserved the structure of the venous layers. Graft pretreatment with CyA flushing did not have a significant immunosuppressive effect.

A new design for a single pass X-ray Self-Amplified Spontaneous Emission (SASE) FEL is proposed. The scheme consists of two undulators and an X-ray monochromator located between them. The first stage of the FEL amplifier operates in the SASE linear regime. After the exit of the first undulator the electron bunch is guided through a non-isochronous bypass and the X-ray beam enters the monochromator. The main function of the bypass is to suppress the modulation of the electron beam induced in the first undulator. This is possible because of the finite value of the natural energy spread in the beam. At the entrance to the second undulator the radiation power from the monochromator dominates significantly over the shot noise and the residual electron bunching. As a result the second stage of the FEL amplifier operates in the steady-state regime when the input signal bandwidth is small with respect to that of the FEL amplifier. Integral losses of the radiation power in the monochromator are relatively small because grazing incidence optics can be used. The proposed scheme is illustrated for the example of the 6 nm option SASE FEL at the TESLA Test Facility under construction at DESY. As shown in this paper the spectral bandwidth of such a two-stage SASE FEL (Δλ/λ⋍ 5 × 10 −5 ) is close to the limit defined by the finite duration of the radiation pulse. The average brilliance is equal to 7 × 10 24 photons/(s × mrad 2 × mm 2 × 0.1% bandw.) which is by two orders of magnitude higher than the value which could be reached by the conventional SASE FEL. The monochromatization of the radiation is performed at a low level of radiation power (about 500 times less than the saturation level) which allows one to use conventional X-ray optical elements (grazing incidence grating and mirrors) for the monochromator design.

Over a 7-month period, a 54-year-old male with poorly-controlled diabetes mellitus, chronic hepatitis C infection, chronic low-back pain, and active intravenous drug abuse developed Methicillinresistant Staphylococcus aureus (MRSA) endocarditis, L1-L2 spondylodisciitis with vertebral osteomyelitis, and a psoas abscess (Figure 1, timeline). He initially presented with pneumonia and persistent MRSA bacteremia (Figure 1, Admission #1), for which he received a prolonged course of vancomycin and linezolid. Few days after completing treatment, he presented with recurrence of fever, generalized weakness, and worsening back pain (Figure 1, Admission #2). During this hospitalization, he was found to have infective endocarditis, L1-L2 spondylodisciitis with vertebral osteomyelitis, and a small psoas abscess. The psoas abscess was deemed too small for percutaneous drainage or surgical debridment. He received one week of gentamicin and five-week course of daptomycin at a long-term nursing facility; he declined further antibiotic therapy and left the nursing facility. One week later, he presented to the infectious disease outpatient clinic for routine follow-up. At this time, his chronic low-back pain remained unchanged and he had no fever. He was hospitalized (Figure 1, Admission #3) after routine blood cultures grew MRSA in four sets (within 24 hours). During this hospitalization, a contrast-enhanced T1 magnetic resonance image (MRI) showed a large psoas abscess (Figure 2, panel A, arrow) extending into L1-L2 vertebral bodies (stars). A transverse view showed epidural extension (Figure 2, panel B, arrowhead) and left kidney displacement by the psoas abscess (arrow). During this period, he underwent catheter drainage of the abscess and received vancomycin and gentamycin. Due to continued infection (persistently positive blood cultures), he underwent L1-L2 vertebrectomy, cord decompression, debridement, and spinal reconstruction. A postoperative lateral radiograph shows T10-L4 posterior internal fixation of the spinal cord (Figure 2, panel C, arrows) and installation of a mechanical distractable interbody device (arrowhead). After a prolonged course of antibiotics, although the patient declined them intermittently, he had resolution of the infection. He was hospitalized multiple times (Figure 1, Admissions #4-6) with worsening back pain and suicide ideation. Although he had no fever and the abscess had resolved on repeated tomographic scanning, he had persistent MRSA bacteremia. During these last three hospitalizations, he received intermittent doses of vancomycin (due to patient declining to receive intravenous antibiotics) and trimethoprim-sulfamethoxazole. He left the institution against medical advice several times and eloped from a long-term nursing facility. During the three months after hospital discharge, the institution attempted to contact him ten times, without success. He is lost to follow-up. A Dreaded Complication of MRSA Infection

Previous studies of starch utilization by the gram-negative anaerobe Bacteroides thetaiotaomicron have demonstrated that the starch-degrading enzymes are cell associated rather than extracellular, indicating that the first step in starch utilization is binding of the polysaccharide to the bacterial surface. Five transposon-generated mutants of B. thetaiotaomicron which were defective in starch binding (Ms-1 through Ms-5) had been isolated, but initial attempts to identify membrane proteins missing in these mutants were not successful. We report here the use of an immunological approach to identify four maltose-inducible membrane proteins, which were missing in one or more of the starch-binding mutants of B. thetaiotaomicron. Three of the maltose-inducible proteins were outer membrane proteins (115, 65, and 43 kDa), and one was a cytoplasmic membrane protein (80 kDa). The genes encoding these proteins were shown to be clustered in an 8.5-kbp segment of the B. thetaiotaomicron chromosome. Two other loci defined by transposon insertions, which appeared to contain regulatory genes, were located within 7 kbp of the cluster of membrane protein genes. The 115-kDa outer membrane protein was essential for utilization of maltoheptaose (G7), whereas loss of the other proteins affected growth on starch but not on G7. Not all of the proteins missing in the mutants were maltose regulated. We also detected two constitutively produced proteins (32 and 50 kDa) that were less prominent in all of the mutants than in the wild type. Both of these were outer membrane proteins.

The results of 26 carotid-subclavian bypass (CSB) and 17 axillo-axillary bypass (AAB) procedures, performed to treat symptomatic lesions of the proximal subclavian artery, were reviewed. Nine graft failures (seven CSB and two AAB) occurred (mean follow-up: CSB = 60.5 +/- 41 months; AAB = 67.8 +/- 48 months). All CSB graft thromboses were observed in patients with an associated ipsilateral carotid lesion, surgically treated or not (p less than 0.05). Cumulative 5- and 10-year patency rates were 78.3 and 62.9% for the CSB group and 87.9% for the AAB group (N.S.). In patients with an associated ipsilateral carotid lesion, 5- and 10-year patency rates were 66.0% and 40.8% for the CSB group and 100% for the AAB group (p less than 0.05). Both the surgical procedures were safe and effective with excellent results in terms of operative mortality, major morbidity and long-term patency. CSB is the procedure of choice for the treatment of proximal subclavian artery disease for its physiological characteristics and for graft shortness. However AAB must be considered a suitable alternative and preferred when a concomitant ipsilateral carotid lesion is present. Recurrence of carotid stenosis or carotid lesion progression may cause the carotid-subclavian failure.

We have measured photoionization cross sections and photoelectron asymmetry parameters for each of the core levels of N2O. We have also carried out frozen‐ and relaxed‐core Hartree–Fock studies of these cross sections so as to better understand the underlying shape resonant structure and the role of electronic relaxation in these processes. A broad shape resonance is observed in each of the core‐hole cross sections at 10‐20 eV kinetic energy and there is some evidence of a second shape resonance near the thresholds, an energy region which is not accessible experimentally. The cross sections also exhibit site‐specific behavior with maxima at widely separated photoelectron kinetic energies. These differences probably arise from the fact that photoelectron matrix elements for different core orbitals probe different regions of the shape resonant orbital which extends over the entire molecule. Although the higher energy shape resonances appear quite similar, Hartree–Fock studies show that the central nitrogen resonance is more sensitive to effects of electronic relaxation than the terminal nitrogen or oxygen resonances. Large differences are also seen between the photoelectron asymmetry parameters for the central and terminal atoms.

In vast regions of the universe highly charged ions (HCI [1, 2]) are the predominant form of visible matter. Their importance extends to high-temperature terrestrial plasmas, such as those used in fusion research. Yet, accurate prediction of their electronic structure remains a challenge for theory due to the strong electromagnetic field in which the remaining bound electrons dwell. Experimental accuracy has now reached the performance limits of conventional photon spectroscopy in the soft and hard x-ray regions. In this work [3], we report on the resonant laser excitation of the 22S1/2—22P1/2 transition of the Li-like Fe22P1/223+ ion at 48.6 eV, an energy range hitherto unattainable with powerful lasers. The HCI stored in an electron beam ion trap (EBIT [4]) were resonantly excited by ultra-brilliant radiation generated at the Free electron LASer in Hamburg (FLASH [5]). While yielding a relative statistical error of only 2.2·10−5, and extending laser spectroscopy on HCI from the near ultraviolet [6] to the soft X-ray region, this novel experiment demonstrates immediate potential to push the current limits of precision by orders of magnitude. Such experiments allow to verify predictions of quantum electrodynamics (QED) in a strong field environment where perturbation theory [7, 8] fails. Future EBIT experiments at upcoming x-ray free electron lasers (X-FEL) like the Stanford Linear Coherent Light Source (LCLS) or the European X-FEL will pave the way for laser spectroscopy into the hard x-ray region.

To determine factors influencing results of operation for proximal brachiocephalic arterial disease, a 16-year review of 74 consecutive patients was undertaken. A total of 62 subclavian, 14 common carotid, 6 innominate, and 2 vertebral arteries were revascularized during 79 procedures. The approach was transthoracic in 12 operations and extrathoracic in 67. Mean follow-up was 57 +/- 45 months. Two patients (2.5%) died of stroke after extrathoracic revascularization of the common carotid artery. Cumulative 5-year and 10-year freedom from neurological events was 81% and 75%, respectively. The best results were obtained with transthoracic procedures, with revascularization of the subclavian artery rather than the common carotid artery, and in operations performed in patients without associated distal carotid disease. In view of the recent progress in operative techniques and postoperative surgical care, the choice between the transthoracic approach and the extrathoracic approach should not be biased; rather, they should remain equal and viable alternatives based on anatomical and clinical features of the individual patients.

During the last fifteen years, we performed a total of 855 aortofemoral re constructions. Fifteen (1.75%) grafts were surgically removed (completely or partially) owing to a severe infection (Szilagyi: Grade 3) at a mean of 66.3 months (SD ± 37.9) after their implantation. Diagnosis was always clinically evident. In 10 patients, the graft was partially removed (one or two limbs). In 3 of the 10, graft infection progressed requiring complete graft removal after a mean of 18.6 days. In the other 5 patients, the graft was removed "in toto" at the time of the first operation. In 9 cases, revascularization was accomplished by means of a "remote" takeoff reconstruction (thoracic aorta or axillary ar tery), whereas in 8 cases (3 recurred) reconstruction was performed with a "local" takeoff reconstruction (stump or aortoiliofemoral arteries). One patient was not revascularized, because the limb was already amputated. Recurrence of infection was higher in the patients treated by partial removal of the graft (p < 0.05), even though the stump sterility was always evaluated by means of intraoperative culture. The mortality of patients with recurrence of infection was 66.6%. Multiple operations of the femoral site were considered a factor in causing aortofemoral graft infection (p < 0.01). Diabetes was not considered a factor in causing infection (p n.s.). Grafts with remote takeoff reconstruction have better long-term results in terms of limb salvage and survival when compared with local takeoff recon struction (p < 0.05).