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Botulism is caused by botulinum neurotoxin (BoNT), the most poisonous substance known. Potential use of BoNT as a biothreat agent has made development of sensitive assays for toxin detection and potent antitoxin for treatment of intoxication a high priority. To improve detection and treatment of botulism, molecular evolution and yeast display were used to increase the affinity of two neutralizing single chain Fv (scFv) antibodies binding BoNT serotype A (BoNT/A). Selection of yeast displayed scFv libraries was performed using methods to select for both increased association rate constant (k(on)) and decreased dissociation rate constants (k(off)). A single cycle of error prone mutagenesis increased the affinity of the 3D12 scFv 45-fold from a K(D) of 9.43x10(-10)M to a K(D) of 2.1x10(-11)M. Affinity of the HuC25 scFv was increased 37-fold from 8.44x10(-10)M to 2.26x10(-11)M using libraries constructed by both random and site directed mutagenesis. scFv variable region genes were used to construct IgG for use in detection assays and in vivo neutralization studies. While IgG had the same relative increases in affinity as scFv, (35-fold and 81-fold, respectively, for 3D12 and HuC25) higher solution equilibrium binding constants were observed for the IgG, with the 3D12 K(D) increasing from 6.07x10(-11)M to 1.71x10(-12)M and the HuC25 K(D) increasing from 4.51x10(-11)M to 5.54x10(-13)M. Affinity increased due to both an increase in k(on), as well as slowing of k(off). Higher affinity antibodies had increased sensitivity, allowing detection of BoNT/A at concentrations as low as 1x10(-13)M. The antibodies will also allow testing of the role of affinity in in vivo toxin neutralization and could lead to the generation of more potent antitoxin.

A nondestructive radiation detector unit is under construction at the TESLA Test Facility at DESY providing monitoring of the radiation (pulse energy, transverse intensity distribution, and statistical properties). The concept of the detector design is based on experience obtained during operation of TTF FEL, Phase 1. Key element of the detector is a wide dynamic range micro-channel plate (MCP) which detects scattered radiation from a thin gold wire crossing photon beam. Operating wavelength range of the detector is from 6 to 100 nm . An important feature of the MCP-based detector is that it is capable to cover all dynamic range of the radiation intensity, from the level of spontaneous emission up to the saturation level of SASE FEL.

Yeast display of antibody fragments has proven to be an efficient and productive means for directed evolution of single-chain Fv (scFv) antibodies for increased affinity and thermal stability and, more recently, for the display and screening of a non-immune scFv and immune Fab libraries. A major strength of yeast display as a novel antibody discovery platform is the ability to characterize the binding properties, i.e., the affinity and epitope binding characteristics, of a clone without the need for subcloning, expression and purification of the scFv. This review focuses on novel attributes of yeast display for antibody engineering endeavors.

A beamline designed to reduce the spectral bandwidth of the DESY XUV FEL is described. The beamline is intended to cover the wavelength range from 6.4 to 50 nm with three variable line spacing gratings. A plane mirror in front of the grating is used to maintain constant magnification in the dispersion direction. The electric field generated by the first undulator at three wavelengths, 6.4, 13, and 25 nm, is propagated through the beamline. The results show that the beamline has the resolution and imaging properties required for seeding the second undulator at these wavelengths.

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.

Background: Dislocation injuries of the glenohumeral joint are common in the general public and generally are corrected without complication. One serious complication with shoulder dislocations, or the subsequent reduction, is a lesion to the axillary artery. This specific complication is most frequently seen in the elderly population, where vascular structures have become less flexible. Also, these injuries are most common in association with anterior dislocations of the shoulder. Objectives: To bring awareness to the possibility of axillary artery injury with inferior dislocation of the shoulder, the treatment options, and a review. Case Report: We report a 15-year-old male athlete who inferiorly dislocated his shoulder during wrestling practice. The injury was reduced at the scene with manual traction and the patient was transferred to our clinic for evaluation. The patient was determined to have a pseudoaneurysm of the axillary artery, and the history and treatment of the illness are presented. Conclusion: Axillary artery injuries secondary to shoulder dislocations are rare, especially in the young athlete, and proper recognition and treatment offer patients a full recovery.

The local structure of the CuO2 planes in Nd2−xCexCuO4−δ (x=0, 0.15; δ∼0.01) has been examined by temperature-dependent Cu K-edge extended X-ray absorption fine structure (EXAFS) spectroscopy. Three different Cu–O distances can be extracted up to at least 100 K, indicating that the atomic structure of the CuO2 planes deviates from the T′ structure much more than it was expected. Positions of the displaced O1 atoms for x=0.15 were obtained from comparative analysis of the experimental and calculated polarized Cu K-edge X-ray absorption near-edge structure, taking into account many-body excitations in the CuO2 planes.

The creation of a core hole in a molecule leads to vibrationally and electronically excited states of the resulting ion as the system adjusts to the new molecular potential. These can be observed in the corresponding photoelectron spectrum as vibrational fine structure on the main line and as satellite excitations, respectively. In the region near the photoelectron threshold, however, other phenomena occur, such as shape resonances, multi-electron excitations and conjugate satellite processes, which affect the partial cross-sections of the various channels. As an example, we present C 1s photoelectron spectra of ethene (C 2 H 4 ) measured with high energy resolution in the near-threshold region. The vibrational fine structure on the C 1s −1 line can be fitted with two progressions with energies of 185(±5) meV and 424(±10) meV, which can be assigned to totally symmetric modes. It is expected that vibronic coupling occurs, as in the case of the corresponding photoabsorption spectrum, and that an antisymmetric stretching mode contributes to the higher energy progression. This cannot be determined from the fit, however. There is no definitive evidence for a shape resonance in the C 1s single-hole cross-section. In addition, the C 1s shake-up satellite spectrum was also measured with high resolution in the near-threshold region. Apart from the well-resolved π–π* satellites, S 0 and S 1 , the measurements revealed several other peaks. Their partial cross-sections and asymmetry parameters indicate the existence of conjugate processes.

The C 1 s −π ∗ band in the high-resolution photoabsorption spectra of the ethyne isotopomers C2H2, C2D2 and C2HD is found to be dominated by vibronic coupling effects. There is quantitative agreement between experiment and a recent theoretical model which treats vibronic coupling in both the core and valence orbital spaces. The theoretical analysis shows that a strong excitation of the bending modes dominates the observed spectra.

Background. The aim of this study was to investigate surgical indications and the long-term outcomes of aortoliofemoral reconstructions in adults younger than 45 years. Methods. Between 1973 and 1990, 1256 patients underwent infrarenal abdominal aortic reconstruction for aortoiliofemoral occlusive disease. Sixty-eight (5.4%) patients (group 1) were less than 45 years old and form the basis of the analysis. They were retrospectively compared with two additional groups of patients 45 years and older selected from the entire series. Patients in group 2 (n = 100) were randomly chosen to determine differences in risk factors, associated diseases, operative indications, preoperative findings, and outcomes. Patients in group 3 (n = 70) were matched with those in group 1 for gender, risk factors, associated diseases, preoperative findings, and operative indications to assess the importance of age in determining the short- and long-term outcomes of aortoiliofemoral reconstructions. Results. Postoperative mortality rates (1.5%, 4%, and 4.3% for groups 1, 2, and 3, respectively) and major complication rates (4.4%, 7%, and 7.1% for groups 1, 2, and 3, respectively) were comparable among the three groups. Ten-year secondary patency rates were 84.6%, 70.6%, and 80.3%, for groups 1, 2, and 3, respectively (p = not significant). Ten-year limb salvage rates were 86.9%, 78.2%, and 80.6%, for groups 1, 2, and 3, respectively (p = not significant). During follow-up a significantly higher percentage of myocardial infarction was recorded in group 1 as compared with group 2 (p < 0.03) and group 3 (p < 0.04). The 10-year survival rate for group 1 was significantly lower than that of group 2 (29.0% versus 46.9%; p < 0.005). Conclusions. Aortoliofemoral reconstruction in patients younger than 45 years is a safe procedure with low operative risks and good long-term results in patency and limb salvage rates. However, life expectancy is poor because of the high incidence of deaths related to coronary artery disease.

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.

We have measured the C 1s near-edge photoabsorption spectrum of the ethene isotopomers C 2 H 4 , C 2 D 4 , (1, 1)C 2 H 2 D 2 and cis-C 2 H 2 D 2 at high resolution using order-sorted, monochromatised undulator radiation. An analysis of the vibrational fine structure on the 1s-π ∗ band indicates strong excitation of non-totally symmetric modes and provides direct evidence for symmetry breaking and core hole localisation.

Early results of laser-assisted balloon angioplasty (LABA) and peripheral directional atherectomy (PDA) are encouraging. The true value of these procedures has remained in doubt, however, because of the absence of data on long-term objective patency rates.From August 1988 through October 1993, LABA and PDA were performed on 151 limbs of 124 patients. Presenting symptoms were mild-to-severe claudication in 128 limbs (63 LABA, 65 PDA) and rest pain or necrosis in 23 (7 LABA, 16 PDA). Seventy-seven percent of the atherosclerotic lesions were localized in the iliofemoral tract (77% LABA, 76% PDA). Seventy limbs were treated with LABA and 81 with PDA.Initial hemodynamic and arteriographic success was achieved in 46 LABA limbs (66%) and 75 PDA limbs (93%) (P0.002). Mean follow-up was 16 +/- 2 months after LABA and 18 +/- 1 months after PDA. During this time, 32 failures were recorded in limbs treated with LABA, and 29 in limbs treated with PDA. The patency rate at 40 months was 23% in the LABA group and 45% in the PDA group (P0.005). Patency rates were not affected by the length or site of the arterial lesion or the runoff score.PDA had a better long-term patency rate than LABA, but long-term results were dismal with both techniques. PDA appears to have a limited role and LABA no role in the treatment of lower extremity occlusive disease.

Lifetime vibrational interference effects modulate the line shapes observed in high-resolution studies of the decay of ultra-short-lived core—hole excited states in molecules. We have analyzed the decay of the 1σ−1u 1π3g core excited state in O2, where for the first time subsets of vibronic eigenfunctions could be selected. We demonstrate that this type of spectroscopy can be used to verify the predictions of quantum mechanical interference theory describing the time evolution of coherently excited vibrational states on the femtosecond time scale.

In an angle-resolved photoelectron study using synchrotron radiation we have re-investigated the C 1s photoionization of CO and CO 2 in the energy region near threshold where the photoabsorption cross sections are characterized by strong shape resonances and transitions to doubly excited states. The much lower scatter in these new data and the extension of the energy range down to 2–3 eV above threshold have made it possible to identify the strong influence of multi-electron excitations on the single-hole partial cross section and the corresponding asymmetry parameter β. Thus, even the single-hole cross section cannot necessarily be used to recover the “one-electron” profile of the shape resonance.

The X1 undulator on the X-ray ring of the NSLS at Brookhaven is an extremely bright source of soft X-ray photons. On the recently completed spectroscopy beamline X1B we have attempted to utilise the intrinsically narrow beam size and divergence to maximise the intensity throughput in a spherical grating monochromator (SGM). The high power density of the undulator radiation requires the use of water cooled mirrors, entrance slit and grating. Calculations predict that simple side cooled copper pads attached to optical elements will be sufficiently effective that resolution degradation due to thermal deformation of figure error will be negligible in the SGM design. This is confirmed by attainment of resolution superior to other SGMs and the BESSY SX700-II monochromator over the energy range 300–540 eV (C1s−1, N1s−1 and Ols−1). At a resolution comparable to the best so far obtained for the nitrogen N 1s π∗ excitation (401 eV) on other monochromators we have demonstrated an intensity increase, at the sample, of more than three orders of magnitude. The design consideration upon which beamline X1B is based are highly relevant to the construction of soft X-ray monochromators at future synchrotron radiation sources such as the ALS (Berkeley). Elettra (Trieste) and BESSYII (Berlin).

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.

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.)

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.

The records of 125 patients 75 years of age or older with a diagnosis of unruptured abdominal aortic aneurysm were reviewed. Operative mortality was 4.3 percent in 69 patients considered at low risk and 39.8 percent in 13 patients at high risk who underwent aneurysmectomy shortly after diagnosis. Forty-three patients with an asymptomatic abdominal aortic aneurysm initially measuring 3.5 to 6 cm did not undergo aneurysmal resection and were followed for 6 to 72 months (mean 24 months) with serial echography. The mean enlargement rate was 0.48 cm/year. In the 43 patients, resection of the abdominal aortic aneurysm was performed for aneurysmal expansion to greater than 6 cm, development of symptoms, or a sudden change in aneurysmal diameter. Two patients were lost to follow-up, 21 underwent elective resection, aneurysms ruptured in 2, 9 died from other causes, and 9 were alive and asymptomatic at last follow-up. An aggressive surgical approach seems appropriate, even in the asymptomatic elderly patient with a small aneurysm of 4.5 to 6 cm. Serial echographic measurement appears useful in determining which patients with a very small aneurysm of less than 4.5 cm or who are considered to be high risk surgical candidates require elective aneurysmectomy.

A 7-year experience with 90 polytetrafluoroethylene (PTFE) femoropopliteal bypass grafts in the above-knee (AK) position is presented. The 5- and 7-year actuarial patency rate was 58.3%. No statistical difference was found between the patency rate of this series and that of a group of 17 AK and 77 below-knee (BK) femoropopliteal bypass grafts performed during the same period with the autologous saphenous vein (ASV). During the follow-up period (range 6 to 84 months, mean 42 months) a new bypass in a more distal location was required in 20 limbs. The ASV was available in seven of the eight PTFE graft failures and in only one of the 12 ASV failures. The 3-year patency rate of these new groups was 58.3% and 16.7%, respectively (p

The performance and application of an ultrahigh vacuum compatible constant-deviation double-crystal monochromator (JUMBO) in operation at SSRL is demonstrated. The monochromator can be operated with any of four pairs of crystals interchangeable in situ. An electronic maximum search feedback loop optimizes the intensity of the spatially fixed outgoing beam as the photon energy is scanned. The monochromatic beam is focused (∼1.5 mm × 5 mm) onto the sample by a toroidal mirror. Monochromator crystals of beryl(10 1 0), InSb(111) and Ge(111) have been tested in the energy regions 800−1540 eV, 1690–4000 eV and 1930–4500 eV, respectively. The performance of these crystals with regard to the resolution, the intensity, the level of scattered light, and the contribution of higher orders have been determined. Various effects arising from a radiation-induced temperature gradient in the monochromator crystals are discussed. Novel studies of bulk and surface properties of materials by angle-resolved photoemission, X-ray induced Auger spectroscopy, photon-stimulated ion desorption, bulk and surface extended X-ray absorption fine structure (EXAFS and SEXAFS) measurements in this previously inaccessible energy region of the electromagnetic spectrum are also discussed.

Among 486 patients undergoing repair for abdominal aortic aneurysm (AAA) during a 12-year period, 30 (6.2%) had evidence of "inflammatory" AAA. One patient (3%) had acute rupture, and six patients (20%) had chronic contained rupture. Ureteral obstruction was evident in 20% of the patients. In the early period of the study there were two postoperative deaths and operative time and blood loss were significantly increased. In the last period of the study, no attempt was made to separate the duodenum and the ureters from the aneurysm; there was no operative mortality, and operative time and blood loss were similar to that of patients with atherosclerotic aneurysms. In 23 of 100 specimens of atherosclerotic AAA, microscopic findings resembling inflammatory AAA were found. On the basis of our study we conclude the following: (1) Inflammatory AAAs are simply atherosclerotic aneurysms that show an unusual accentuation of the chronic inflammation observed in relation to atherosclerotic aneurysms. (2) Operative technique should be modified to avoid excessive dissection and lysis of ureters and duodenum. (3) Excellent early and late results can be expected with proper surgical technique. (4) The causes of AAA are multiple, and chronic contained rupture of the aneurysm and reactive lymphatic hyperplasia might play a role of greater significance than previously thought. (J Vasc Surg 1989;9:643–50.)

From May 1974 to October 1983, 82 patients with severe bilateral carotid disease had unilateral carotid endarterectomy (CE) on the symptomatic side (group I). The carotid artery contralateral to the endarterectomy was severely stenosed (lumen diameter reduction 51% up to 99%) and it was not repaired for different reasons. Group I patients were compared with 78 patients who had bilateral CE (group II), matched with group I for associated diseases, operative indication, and angiographic findings. In this analysis, only neurologic deficits referable to the contralateral hemisphere were considered. There was a higher incidence of later neurologic deficits in the group I patients; however, this difference was not statistically significant. In group I, the occurrence of late neurologic deficits was statistically correlated to (1) severity of stenosis, (2) presence of large compound ulceration, and (3) history of previous stroke. Stepwise logistic regression analysis identified two groups of patients at higher risk for late neurologic deficits (1) patients with stenosis 75% or greater and large ulceration and (2) patients with stenosis 75% or greater and previous stroke. CE on the asymptomatic contralateral side should be considered in selected patients at high risk for late neurologic events at a surgical center with an established low incidence of perioperative complications. A nonoperative policy with careful follow-up is warranted in the remaining cases. (J VASC SURG 1988;8:453-9.)

The success of aortofemoral reconstruction in patients with superficial femoral artery occlusion depends on the restoration of a satisfactory pulsatile flow to the deep femoral artery. In 18 patients with multilevel disease, widespread involvement of the deep femoral artery, and poor distal outflow, we performed an eversion endarterectomy of the proximal segment of the superficial femoral artery and constructed an end-to-side anastomosis between this segment and the distal deep femoral artery. In 10 patients, the reconstruction was performed after thrombectomy of the occluded aortofemoral graft, and in 8 the two reconstructions were simultaneous. The actuarial patency rate was 93.5 percent at 1 year and 75.2 percent at 5 years. Four late femorodistal bypasses were performed that gave an actuarial limb salvage rate of 68.8 percent at 1 year and 61.6 percent at 5 years. In selected cases, this technique is a valid alternative to an extended profundoplasty or to a femorodistal bypass.

In the past 14 years, 22 patients (25 operated sides), with occlusion of the internal carotid artery (ICA), underwent ipsilateral external carotid artery (ECA) endarterectomy at our institution. Operative indications were amaurosis fugax in 13 sides and nonlateralizing transient ischemic attacks in the remaining 12. There were no operative deaths. One patient suffered a minor stroke after operation. Follow-up ranged from 6 to 110 months (median 36 months). In 16 cases, simple endarterectomy with or without vein patch closure was performed (type I). In two cases the ostium of the ICA was occluded with interrupted sutures after endarterectomy (type II). In the remaining seven cases the ICA was transposed as a patch over the endarterectomized ECA after endarterectomy (type III). All but six patients (six sides) underwent duplex scanning or angiography during follow-up. Four of nine patients with previous nonlateralizing symptoms had persistent symptoms after operation, whereas none of those with previous amaurosis fugax did. Recurrent occlusive disease was more common in type I reconstructions (p less than 0.05). Proper ECA reconstruction results in long-term patency. In the patient with ipsilateral ICA occlusion, transposition of the ICA as a patch over the endarterectomized ECA offers a valid hemodynamic solution. Objective parameters are needed to identify patients with nonlateralizing symptoms who will benefit from operation.

An increase of the ferromagnetic Curie temperatures with increasing conduction electron concentration known for Gd 3− x S 4 is observed also in Ce 3− x S 4 . We determined the magnetic influence on the conduction electron scattering by comparing the resistivity of these compounds with the results for the nonmagnetic La 3− x S 4 . The magnetic contributions to the resistivity vary strongly with conduction electron concentration.