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Aim: The treadmill walking test with post-exercise pressure measurement can be used as a diagnostic test and could classify peripheral arterial disease of the lower limbs. It can also exclude the diagnosis allowing to raise the possibility of differential diagnoses. In this study, we assessed the feasibility of performing treadmill test by advanced practice nurse to assess suspected lower extremity peripheral artery disease patients., Design and Method: This is a longitudinal monocentric study to assess the feasibility of a treadmill walking test performed by an advanced practice nurse. The primary endpoint was the number of tests performed during this period. The secondary objectives were to evaluate the reasons for requesting the test, the main results obtained in terms of the test's contribution and diagnoses, and patients' clinical characteristics., Results: From February to May 2023, amongst 31 patients who underwent the treadmill walking test, 4 tests were able to rule out peripheral arterial disease and to detect differential diagnoses. For the remaining 27 patients, 4 had stage IIa of the Leriche classification, 23 had stage IIb, 2 of which were associated with a narrow lumbar spine. In contrast to the usual report, the APN's report on the walking test included an identification of cardiovascular risk factors, as well as a possible medical reorientation linked to the correction of a detected cardiovascular risk factor., Conclusion: The treadmill walking test can be performed by an advanced practice nurse. He/She added a comprehensive/global patient management, with the detection of cardiovascular risk factors. This new profession led to an increase in the number of tests performed of more than 50% over the period and reduced the time to access the test., (Copyright © 2024 The Author(s). Published by Elsevier Masson SAS.. All rights reserved.)

The endovascular approach is widely used in the management of aortic isthmic rupture. Even if it remains less invasive than conventional surgery, a life-threatening complications are possible. We report the case of a young female patient presenting a stent-graft migration during the deployment with total obstruction of the supra-aortic vessels. We describe the therapeutic management with a cerebral rescue procedure followed by a delayed surgical repair., Competing Interests: Déclaration de liens d'intérêts Les auteurs déclarent ne pas avoir de liens d'intérêts., (Copyright © 2023 Elsevier Masson SAS. All rights reserved.)

Background: Surgical repair of aortic arch pathology is complex and associated with significant morbidity and mortality. Alternative approaches have been developed to reduce these risks, including the use of thoracic stent-grafts with fenestrations or in combination with bypass procedures to maintain supra-aortic trunk blood flow. Branched stent-grafts are a novel approach to treat aortic arch pathology., Methods: Consecutive patients with aortic arch disease presenting to a single university hospital vascular centre were considered for branched stent-graft repair (October 2010 to January 2017). Patients were assessed in a multidisciplinary setting including a cardiologist, cardiac surgeon and vascular surgeon. All patients were considered prohibitively high risk for standard open surgical repair. The study used reporting standards for endovascular aortic repair and PROCESS (Preferred Reporting of Case Series in Surgery) guidelines., Results: Some 30 patients (25 men) underwent attempted branch stent-graft repair. Mean age was 68 (range 37-84) years. Eighteen patients had chronic aortic dissection, 11 patients had an aneurysm and one had a penetrating ulcer. Fourteen patients had disease in aortic arch zone 0, six in zone 1 and ten in zone 2. Twenty-five patients had undergone previous aortic surgery and 24 required surgical revascularization of the left subclavian artery. Technical success was achieved in 27 of 30 patients. Four patients had an endoleak (type Ia, 1; type II, 3). The in-hospital mortality rate was three of 30. Mean length of follow-up was 12·0 (range 1·0-67·8) months, during which time 12 patients required an aortic-related reintervention., Conclusion: Repair of aortic arch pathology using branched stent-grafting appears feasible. Before widespread adoption of this technology, further studies are required to standardize the technique and identify which patients are most likely to benefit., (© 2018 BJS Society Ltd Published by John Wiley & Sons Ltd.)

Objective: The aim of this study was to evaluate a new 3D Workstation workflow (EVAR Assist, Advantage Windows, GE Healthcare, Chalfont, UK) (EA-AW) designed to simplify complex EVAR planning., Patients and Methods: All pre-operative computed tomography (CT) scans of patients who underwent repair at our institution of a complex aortic aneurysm using fenestrated endovascular repair (f-EVAR) between January and September 2014, were reviewed. For each patient, imaging analysis (12 measures: aortic diameters and length and "clock position" of visceral artery) was performed on two different workstations: Aquarius (TeraRecon, San Mateo, CA, USA) and EA-AW. According to a standardized protocol, three endovascular surgeons experienced in aortic endograft planning, performed image analyses and data collection independently. We analyzed an internal assessment between observers (on the Aquarius 3DWS) and an external assessment comparing these results with the planning center (PC) data used to custom the fenestrated endograft of the patients enrolled in this study. Finally, we compared both 3DWS data to determine the accuracy and the reproducibility. A p-value < .05 was considered as statistically significant. Complete agreement between operators was defined as 1.0., Results: Intra- and inter-observer variability (interclass correlation coefficients - ICC: 0.81-.091) was very low and confirmed the reliability of our planners. The ICC comparison between EA-AW and Aquarius was excellent (> 0.8 for both), thus confirming the reproducibility and reliability of the new EA-AW application. Aortic and iliac necks diameters and lengths were similarly reported with both workstations. In our study, the mean difference in distance and orientation evaluation of target vessels evaluated by the two workstations was marginal and has no impact on clinical practice in term of device manufacturing., Conclusions: We showed that complex EVAR planning can be performed with this new dedicated 3D workstation workflow with a good reproducibility.

Objective: To assess short- and long-term movement of renal arteries after fenestrated endovascular aortic repair (FEVAR)., Methods: Consecutive patients who underwent FEVAR at one institution with a custom-made device designed with fenestrations for the superior mesenteric (SMA) and renal arteries, a millimetric computed tomography angiography (CTA), and a minimum of 2 years' follow-up were included. Angulation between renal artery trunk and aorta, clock position of the origin of the renal arteries, distance between renal arteries and SMA, and target vessel occlusion were retrospectively collected and compared between the pre-operative, post-operative (<6 months), and last (>12 months) CTA., Results: From October 2004 to January 2014, 100 patients met the inclusion criteria and 86% of imaging was available for accurate analysis. Median follow-up was 27.3 months (22.7-50.1). There were no renal occlusions. A significant change was found in the value of renal trunk angulation of both renal arteries on post-operative compared with pre-operative CTA (17° difference upward [7.5-29], p < .001), but no significant change thereafter (p = .5). Regarding renal clock positions (7.5° of change equivalent to 15 min of renal ostial movement): significant anterior change was found between post-operative and pre-operative CTA (15 min [0-30], p = .03 on the left and 15 min [15-30], p < .001 on the right), without significant change thereafter (15 min [0-30], p = .18 on the left and 15 min [0-15] on the right, p = .28). No changes were noted on the distance between renal and SMA ostia (difference of 1.65 mm [1-2.5], p = .63)., Conclusion: The renal arteries demonstrate tolerance to permanent changes in angulation after FEVAR of approximately 17° upward trunk movement and of 15-30 min ostial movement without adverse consequences on patency after a median of more than 2 years' follow-up. The distance between the target vessels remained stable over time. These results may suggest accommodation to sizing errors and thus a compliance with off the shelf devices in favourable anatomies., (Copyright © 2016 European Society for Vascular Surgery. Published by Elsevier Ltd. All rights reserved.)

Objectives: Outcomes are reported in management of post-dissection aneurysms involving the aortic arch and/or thoraco-abdominal segment (TAAA) treated with fenestrated and branched (complex) endografts., Methods: This report includes all patients with chronic post-dissection aneurysms >55 mm in diameter, deemed unfit for open surgery, treated using complex endografts between October 2011 and March 2015. When appropriate, staged management strategies including left subclavian artery revascularization, thoracic endografting, dissection flap fenestration or tear enlargement, and other endovascular procedures were performed at least 3 weeks prior to definitive complex endovascular repair. The following outcome data were collected prospectively at discharge, 12 months and annually thereafter: technical success, endoleaks, target vessel patency, false lumen patency, aneurysm diameter, major and minor complications, re-interventions, and mortality., Results: The cohort comprised 23 patients with a median age of 65 years. Staged procedures were performed in 14 patients (61%). Seven patients with dissections involving the arch were treated with inner branched endografts, and 16 TAAA patients were treated with fenestrated or branched endografts. The technical success rate was 71% following arch repair and 100% following TAAA repair. During early follow up, one of the arch group patients died and one in the TAAA group suffered spinal cord ischemia. The median follow up was 12 months (range 3-48), during which time one patient died of causes unrelated to aneurysm or treatment. Two early re-interventions were performed in the arch group to correct access vessel complications and there were a further two late re-interventions in the TAAA group to treat endoleaks. All target vessels (n = 72) remained patent., Conclusions: This experience indicates that complex endovascular repair of post-dissection aneurysms is a viable alternative to open repair in patients deemed unfit for open surgery. There are insufficient data to allow comparison with the outcome of open surgery in anatomically similar, but fit, patients., (Copyright © 2015 European Society for Vascular Surgery. Published by Elsevier Ltd. All rights reserved.)

Objectives: The aim was to evaluate the current results of aortic arch aneurysm repair using inner branched endografts performed in three high volume aortic endovascular centers and to compare them to the pioneering global experience with this technology., Methods: Included patients underwent repair of aortic arch aneurysms >55 mm in diameter using inner branched endograft technology between April 2013 and November 2014. All patients were deemed unfit for open surgery. Inner branches were designed to perfuse the brachiocephalic trunk and the left common carotid artery in all cases. A left subclavian artery (LSA) revascularization was performed prior to the arch endovascular repair. Data were collected retrospectively in an electronic database. Parameters included length of procedure, fluoroscopy time, contrast volume, technical success, presence of endoleaks, early and late complications, and mortality., Results: Twenty-seven patients were included in the study. Technical success was achieved in all cases. No patients died during the 30 day post-operative period. Early neurologic events included two major strokes (7.4%) and one minor stroke (3.7%). Transient spinal cord ischemia with full recovery was observed in two patients (7.4%). Four patients (14.8%) underwent early (<30 day) re-interventions; these were for an access complication, an ischemic limb and exploration of the left ventricle through a sternotomy in two patients. During follow up (median 12 months), one patient (3.7%) died from a remote thoraco-abdominal aneurysm rupture. There were three Type 2 endoleaks (11.1%). Two re-interventions (7.4%) were performed, one to treat a Type 2 endoleak and one to treat a septic false aneurysm. A significant decrease in overall mortality was observed when comparing patients from the early experience with patients from the current report., Conclusions: The early outcomes associated with this technology are favorable. Branched endografting of aortic arch aneurysms should be considered in patients unfit for open surgery., (Copyright © 2015 European Society for Vascular Surgery. Published by Elsevier Ltd. All rights reserved.)

Objective: The purpose of this study was to analyze immediate and long-term renal outcomes (renal function and renal events) after fenestrated (FEVAR) and branched endovascular aortic aneurysm repair (BEVAR)., Methods: All FEVAR and BEVAR performed between October 2004 and October 2012 were included in this study. Post-operative acute renal failure (ARF) was defined according to the RIFLE criteria. Renal volume (calculated with a 3D workstation) and estimated glomerular filtration rate (GFR) (estimated with the Modification of Diet in Renal Disease [MDRD] formula) were evaluated before the procedure, before discharge, 12 months after, and yearly thereafter. Renal stent occlusion, dissection, fracture, stenosis, kink, renal stent related endoleak, and renal stent secondary intervention were all considered "renal composite events" and analyzed. A time to event analysis was performed for renal events and secondary renal interventions., Results: 225 patients were treated with FEVAR and BEVAR. Renal target vessels (n = 427) were perfused by fenestrations (n = 374), or branches (n = 53). Median follow up was 3.1 years (2.9-3.3 years). Technical success was achieved in 95.5% of patients. Post-operative ARF was seen in 64 patients (29%). Mean total renal volume and eGFR at 1 year, 2 year, and 3 year follow up were significantly lower when compared with pre-operative levels (after BEVAR and FEVAR); the decrease at 3 years was 14.8% (6.7%; 22.2%) (p = .0006) for total renal volume and 14.3% (3.1%; 24.3%) (p = .02) for eGFR. The 30 day and 5 year freedom from renal composite event was 98.6% (95.8-99.6%) and 84.5% (76.5-89.9%) after FEVAR and BEVAR (NS). The 30 day and 5 year freedom from renal occlusion was 99.5% (96.7-99.9%) and 94.4% (89.3-97.1%) after FEVAR and BEVAR (NS)., Conclusion: FEVAR and BEVAR are durable options for the treatment of complex aortic aneurysms and are associated with low renal morbidity, without differences between devices types. The clinical impact of decreasing renal volume over time in these patients is yet to be fully understood., (Copyright © 2015 European Society for Vascular Surgery. Published by Elsevier Ltd. All rights reserved.)

Objectives: This study evaluated a new strategy to assess technical success after standard and complex endovascular aortic repair (EVAR), combining completion contrast enhanced cone beam computed tomography (ceCBCT) and post-operative contrast enhanced ultrasound (CEUS)., Methods: Patients treated with bifurcated or fenestrated and branched endografts in the hybrid room during the study period were included. From December 2012 to July 2013, a completion angiogram (CA) was performed at the end of the procedure, and computed tomography angiography (CTA) before discharge (group 1). From October 2013 to April 2014, a completion ceCBCT was performed, followed by CEUS during the 30 day post-operative period (group 2). The rate of peri-operative events (type I or III endoleaks, kinks, occlusion of target vessels), need for additional procedures or early secondary procedures, total radiation exposure (mSv), and total volume of contrast medium injected were compared., Results: Seventy-nine patients were included in group 1 and 54 in group 2. Peri-operative event rates were respectively 8.9% (n = 7) and 33.3% (n = 18) (p = .001). Additional procedures were performed in seven patients (8.9%) in group 1 versus 17 (31.5%) in group 2 (p = .001). Two early secondary procedures were performed in group 2 (3.7%), and three (3.8%) in group 1 (p = .978). Median radiation exposure due to CBCT was 7 Gy cm(2) (5.25-8) (36%, 27%, and 9% of the total procedure exposure, respectively for bifurcated, fenestrated, and branched endografts). CEUS did not diagnose endoleaks or any adverse events not diagnosed by ceCBCT. Overall radiation and volume of contrast injected during the patient hospital stay in groups 1 and 2 were 34 (25.8-47.3) and 11 (5-20.5) mSv, and 184 (150-240) and 91 (70-132.8) mL respectively (reduction of 68% and 50%, p < .001)., Conclusions: Completion ceCBCT is achievable in routine practice to assess technical success after EVAR. Strategies to evaluate technical success combining ceCBCT and CEUS can reduce total in hospital radiation exposure and contrast medium volume injection., (Copyright © 2015 European Society for Vascular Surgery. Published by Elsevier Ltd. All rights reserved.)

The repair of aneurysms involving the aortic arch is technically and physiologically demanding. Historically, these aneurysms have been treated using open surgical techniques that require cardiopulmonary bypass and deep hypothermic circulatory arrest. Many patients have been deemed "untreatable" and among those selected for surgery there are reported risks of death in 2% to 16.5% and stroke rates ranging from 2% to 18%. "Hybrid arch repair" combines one of a number of open surgical procedures (to secure a proximal landing zone for an endograft) with subsequent or immediate placement of an endograft in the arch and descending aorta. Although this concept is described as "minimally invasive" because it avoids aortic cross-clamping and hypothermic circulatory arrest, the morbidity and mortality rates remain considerable (mortality 0% to 15%, stroke 0% to 11%). Ongoing development of endograft technology has enabled total endovascular repair of complex aortic aneurysms involving the visceral segment, using fenestrated and branched endografts. Encouraging early results in this anatomy have inspired extension of the concept to include the aortic arch and great vessels. These strategies can be considered in patients generally at high-risk for the conventional procedures. However, the endeavour is at an early stage of its development and the arch poses unique challenges including the potential for stroke, angulation of the arch and the great vessel ostia to the arch, extremely high volume flow, three-dimensional pulsation and rotation with the cardiac cycle and the proximity of the aortic valve and coronary arteries.

Objective/background: Spinal cord ischemia (SCI) is a devastating complication following endovascular thoracoabdominal aortic aneurysm (TAAA) repair. In an attempt to reduce its incidence two peri-procedural changes were implemented by the authors in January 2010: (i) all large sheaths are withdrawn from the iliac arteries immediately after deploying the central device and before cannulation and branch extension to the visceral vessels; (ii) the peri-operative protocol has been modified in an attempt to optimize oxygen delivery to the sensitive cells of the cord (aggressive blood and platelet transfusion, median arterial pressure monitoring >85 mmHg, and systematic cerebrospinal fluid drainage)., Methods: Between October 2004 and December 2013, 204 endovascular TAAA repairs were performed using custom made devices manufactured with branches and fenestrations to maintain visceral vessel perfusion. Data from all of these procedures were prospectively collected in an electronic database. Early post-operative results in patients treated before (group 1, n = 43) and after (group 2, n = 161 patients) implementation of the modified implantation and peri-operative protocols were compared., Results: Patients in groups 1 and 2 had similar comorbidities (median age at repair 70.9 years [range 65.2-77.0 years]), aneurysm characteristics (median diameter 58.5 mm [range 53-65 mm]), and length of procedure (median 190 minutes [range 150-240 minutes]). The 30 day mortality rate was 11.6% in group 1 versus 5.6% in group 2 (p = .09). The SCI rate was 14.0% versus 1.2% (p < .01). If type IV TAAAs were excluded from this analysis, the SCI rate was 25.0% (6/24 patients) in group 1 versus 2.1% (2/95 patients) in group 2 (p < .01)., Conclusion: The early restoration of arterial flow to the pelvis and lower limbs, and aggressive peri-operative management significantly reduces SCI following type I-III TAAA endovascular repair. With the use of these modified protocols, extensive TAAA endovascular repairs are associated with low rates of SCI., (Copyright © 2014 European Society for Vascular Surgery. Published by Elsevier Ltd. All rights reserved.)

The treatment of chronic aortic dissection is a major challenge for the vascular surgeon. Close imaging follow-up after the acute episode frequently identifies dilation of untreated aortic segments. Aortic dissection often extends to both the supra-aortic trunks and to the visceral aorta. The poor medical condition that often characterizes these patients may preclude extensive open surgical repair. Recent advances in endovascular techniques provide a valid alternative to open surgery. These complex lesions can now be managed using thoracic branched and fenestrated endografts. However, clinical data are scarce and only 3 small series from 3 high-volume aortic centers are currently available. Careful anatomical study on 3D workstations is mandatory to select patients that are candidates for complex endovascular exclusion; a specific focus on the available working space within the true lumen, extension to the arch and/or the visceral/renal arteries, and false lumen perfusion of visceral vessels is required. An excellent understanding of those anatomic details demands high-quality preoperative CTA. Intraoperative advanced imaging applications are a major adjunct in the achievement of technical success.

Introduction: Endovascular repair of aortic arch aneurysms using an inner-branched device is a new treatment option for patients unfit for open surgery. There are many anatomical restrictions, such as the presence of a mechanical aortic valve that can contraindicate this complete endovascular approach., Report: A new delivery system to overcome this issue has been developed. This new system was used to treat an aortic arch aneurysm 77 mm in diameter in a 37-year-old patient with Marfan's syndrome. The patient was considered to be at major risk for open surgery because of severe respiratory insufficiency following a second sternotomy., Discussion: Total endovascular arch aneurysm repair is no longer contraindicated in patients with a mechanical aortic valve., (Copyright © 2014 European Society for Vascular Surgery. Published by Elsevier Ltd. All rights reserved.)

Background: To assess the accuracy of the aortic outer curvature length for thoracic endograft planning., Methods: Seventy-four patients (58 men, 66.4 ± 14 years) who underwent thoracic endovascular aortic repair between 2009 and 2011 treated with a Cook Medical endograft were enrolled in this retrospective study. Immediate postoperative CT scans were analysed using EndoSize software. Three vessel lengths were computed between two fixed landmarks placed at each end of the endograft: the straightline (axial) length, the centerline length and the outer curvature length. A tortuosity index was defined as the ratio of the centerline length/straightline length. A Student t test and a Pearson correlation coefficient were used to examine the results., Results: We found a significant difference between the centerline length (135.4 ± 24 mm) and that of the endograft (160 ± 29 mm) (p < .0001). This difference correlates with the tortuosity index (r = .818, p < .0001), the endograft length (r = .587, p < .0001), and the diameter of the endograft (r = .53, p < .0001). However, the outer curvature length (161.3 ± 29 mm) and the endograft length (160 ± 29 mm) were similar (p = .792)., Conclusion: The outer curvature length more accurately reflects that of the deployed endograft and may prove more accurate than centerlines in planning thoracic endografts., (Copyright © 2013 European Society for Vascular Surgery. Published by Elsevier Ltd. All rights reserved.)

Introduction: The revascularisation of large (>3 mm) renal arteries emerging from the proximal sealing zone or off the aneurismal wall can be challenging during endovascular aortic aneurysm repair. In this article, we describe various endovascular techniques using custom-made endografts to treat these complex variant anatomies., Cases: Nine patients deemed unfit for open repair with unusual renal vascularisation associated with aortic aneurysms were treated by endovascular means. After three-dimensional (3D) reconstructions on a dedicated workstation, custom-made devices were designed and manufactured. The revascularisation of multiple renal arteries and aberrant origins of renal arteries, associated or not with pelvic kidney or horseshoe kidney, was managed using fenestrated and branched endografts., Results: All target vessels were patent on computed tomography (CT) scan and contrast-enhanced ultrasound evaluation before discharge as well as on the 6-month follow-up. One patient presented a decrease of postoperative glomerular filtration rate over 30% but did not require dialysis. No sac enlargement was depicted, and no reintervention was performed during follow-up. Three type 2 endoleaks were diagnosed., Conclusion: Endovascular treatment with fenestrated and branched endografts should be considered in challenging renal artery anatomies in patients unfit for open repair., (Copyright © 2012 European Society for Vascular Surgery. Published by Elsevier Ltd. All rights reserved.)

A mutant form of the jellyfish cDNA encoding green fluorescent protein (GFP) was fused to the promoter of the Aureobasidium pullulans xylanase gene xynA and the expression vector pxynEGFP was introduced into A. pullulans. In a manner consistent with regulation of the native xynA gene, gfp activity was induced by xylose and repressed by glucose. The marker may be useful for monitoring populations of A. pullulans in situ and for identifying transcriptional control elements of xynA.

Purpose: This study of traumatic liver injuries (LI) in children reviews the authors' management and identifies the indications for surgical intervention., Methods: A total of 11,761 admissions over 13 years to a regional pediatric trauma center were surveyed., Results: LI were identified in 328 children. Mechanisms included 39% pedestrians struck by a vehicle, 34% motor vehicle occupants, 13% falls or discrete blows to the abdomen, 5% bicycle injuries, 5% child abuse, and 4% penetrating injuries. Eighty-seven of patients with LI were treated nonoperatively with a mortality rate of 17%. Six percent of deaths were attributed to the LI and massive hemorrhage, all of which presented with cardiopulmonary resuscitation (CPR) in progress, with the remainder of deaths attributed to massive head, neck, or chest injuries (HNCI, 90%) and sepsis (4%). Surgery was performed in 13% of all LI and included major hepatic vascular injury (MHVI) repairs (34%), hepatorrhaphies (34%), lobectomies (27%), and biliary repairs (4%). Excluding the nonoperative group deaths, the need for blood transfusion of more than 25 mL/kg in the first 2 hours as an indicator of surgical necessity or a MHVI had, respectively, a sensitivity of 34% and 67%, specificity of 98% and 97%, positive predictive value of 79% and 53%, negative predictive value of 89% and 98%, and prediction accuracy of 88% and 95%. In the surgical management group, the mortality rate was 23% with 40% of deaths attributed to MHVI, 30% a combination of MHVI and HNCI, 20% massive HNCI, and 10% sepsis., Conclusions: The majority of pediatric LI are not associated with hemodynamic instability and can be successfully managed nonoperatively (72%). Hemodynamic instability, as defined by the need for blood transfusion in excess of 25 mL/kg within the first 2 hours, was a strong indicator of a MHVI, which was often a lethal injury (70%).

Researchers have applied open path optical sensing techniques to a variety of workplace and environmental monitoring problems. Usually these data are reported in terms of a path-average (or path-integrated) concentration. When assessing potential human exposures along a beam path, this path-average value is not always informative, since concentrations along the path can vary substantially from the beam average. The focus of this research is to arrive at a method for estimating the upper-bound in contaminant concentrations over a fixed open beam path. The approach taken here uses a statistical model to estimate an upper-bound concentration based on a combination of the path-average and a measure of the spatial variability computed from point samples along the beam path. Results of computer simulations and experimental testing in a controlled ventilation chamber indicate that the model produced conservative estimates for the maximum concentration along the beam path. This approach may have many applications for open path monitoring in workplaces or wherever maximum concentrations are a concern.

Aureobasidium pullulans, a cosmopolitan yeast-like fungus, colonizes leaf surfaces and has potential as a biocontrol agent of pathogens. To assess the feasibility of rRNA as a target for A. pullulans-specific oligonucleotide probes, we compared the nucleotide sequences of the small-subunit rRNA (18S) genes of 12 geographically diverse A. pullulans strains. Extreme sequence conservation was observed. The consensus A. pullulans sequence was compared with other fungal sequences to identify potential probes. A 21-mer probe which hybridized to the 12 A. pullulans strains but not to 98 other fungi, including 82 isolates from the phylloplane, was identified. A 17-mer highly specific for Cladosporium herbarum was also identified. These probes have potential in monitoring and quantifying fungi in leaf surface and other microbial communities.

High-resolution in vitro ultrasonography (US) of 20 surgical appendiceal specimens was performed to compare appearances of appendiceal tissue at US with corresponding histologic features. With an articulated-arm system and micropositioner, precise spatial correlation was achieved. As elsewhere in the gastrointestinal tract, five distinct echo layers were observed. Normal and inflamed specimens demonstrated these layers, but the architecture became disorganized and indistinct in cases of appendicitis. Three measurements were made for each specimen: (a) overall cross-sectional diameter, including the lumen, (b) thickness of the submucosal echo layer, and (c) the combined thickness of both walls, excluding the lumen. For the inflamed specimens, a substantial increase in the thickness of the summed wall measurements was found. Wall US appearance alone may be misleading in differentiation of normal and abnormal appendices.

A transportable, remote sensing instrument has been built that is capable of performing real-time quantitative analysis of gas and vapor contaminants of workplace air. The emphasis in this system is on simplicity and sensitivity for use over pathlengths of up to 40 m. A method was developed to overcome the effect of nonanalyte species present in the background spectrum on the quantitation of analytes in the sample spectrum. In addition, results demonstrated that instrument response was proportional to the beam pathlength under homogeneous concentration conditions. The application of software capable of qualitative analysis was also demonstrated.

Conceptual problems with OSHA's use of an absolute standard have led to alternative methods of assessing exposures to toxic materials in the workplace. One of these methods employs a one-sided tolerance limit. This statistical approach is explored from three points of view--identifiability, sampling strategies and statistical power. In general, assessing risk in the work environment with tolerance limits is found to give inadequate answers in several important respects.

This study was carried out to evaluate the possible usefulness of the VCG obtained during right ventricular pacing in the diagnosis of right ventricular necrosis. Myocardial necrosis was produced by injecting 40% formalin into the ventricular walls of 18 open-chest mongrel dogs. The injections were made in the inferior wall of the left ventricle in nine dogs (Group A) and in the inferior wall of the right ventricle in the remaining nine dogs (Group B). Analysis of vectorcardiographic QRS loops obtained during artificial pacing of the right ventricular apex was made before and 60 minutes after the injections. In Group B, but not in Group A, the injections resulted in superior displacement of initial QRS forces as indicated by measurements of time, distance, amplitude and angle. The pacing VCG, performed in serial fashion, is a specific and sensitive means of detecting right ventricular inferior wall necrosis in the experimental animal. Application of these findings to the diagnosis of myocardial infarction in humans requires further investigation.

Daily 8-hr time-weighted average (TWA) measurements may not be independent since production rates, maintenance schedules, work practices, and ventilation can result in trends where consecutive values are correlated (autocorrelation). A sampling program which involves collection of measurements on consecutive days, therefore, can result in biased estimates of the mean and variance of the exposure distribution if a high degree of autocorrelation exists. Three simulated data sets were examined to assess the effects of autocorrelation on the estimation of exposure distributions. Results indicated that about 30% of estimated mean values from a highly-autocorrelated series were outside the 95% confidence interval observed for an uncorrelated series. Three data sets obtained from actual workplaces were found to have relatively little autocorrelation. This suggests that for workplaces such as those analyzed here, a random sampling program may not be necessary, and sequential sampling may produce accurate estimates of the parameters of the exposure distribution.

Adenosine triphosphate (ATP), glycogen, and inorganic phosphorus (Pi) were assayed in myocardial tissues obtained from beating dog hearts subjected to the following procedures: Group 1. Ligation of anterior descending coronary artery(AD) for 60 min. Group 2. Perfusion of the AD with 20 mM glucose in Ringer's solution containing 1 mU regular insluin/ml, for 60 min. Group 3. Ligation of the AD for 60 min, followed by release of the ligature with re-establishment of blood flow for 30 min. Group 4. Perfusion of the AD with 20 mM glucose in Ringer's solution containing 1 mU/ml regular insulin for 60 min, followed by re-establishment of blood flow for 30 min. Samples from normal myocardium (N zone) and from the area supplied by the AD (I zone) were simultaneously obtained and the level of metabolites compared. In all four groups, ATP was significantly lower in I than N zone. However, ATP values were lower in N zone in group 1 as compared with the other groups (p less than 0.05) and higher in I zone in group 3 versus groups 1 and 2 (p less than 0.05). Glycogen was lower in I than N zones to a similar degree in all the groups. However, it was higher in the I zone in group 3 than in group 1 (p less than 0.05). Pi was significantly higher in I zone versus N zone only in group 1 (p less than 0.05). These data suggest that, the the beating dog heart, ATP and glycogen preservation in a myocardial segment rendered ischemic for 1 hour is best achieved by re-establishing circulation. Glucose infusion into the ischemic segment did not contribute significantly to the ATP stores in that segment but may have exerted a protective effect on the nonischemic zones, possibly by providing a high glucose level in the circulating blood. This protection was equally well achieved by release of the ligature with or without prior glucose infusion. The increase in Pi in the ischemic zone in the dogs with coronary ligation only is probably related to accumulation of the ion under ischemic and hypoxic conditions.

This study was carried out to evaluate the possible usefulness of the VCG in the diagnosis of right ventricular necrosis. Myocardial necrosis was produced by injecting 40% formalin into the ventricular walls of 21 open-chest mongrel dogs. The injections were made in the inferior wall of the left ventricle in eight dogs (Group A) and in the inferior wall of the right ventricle in 13 dogs (Group B). Analysis of vectorcardiographic QRS loops obtained before and two hours after the injections revealed that both left and right ventricular necrosis resulted in a decrease in: maximum inferior amplitude, inferior amplitude at 10 and 20 msec. and maximum frontal plane angle. In Group A, six dogs had counterclockwise initial forces in the frontal plane before the injections and these became clockwise following the injections. In Group B, nine dogs had counterclockwise initial forces in the frontal plane before the injections and these remained counterclockwise following the injections. The only consistent QRS change in scalar ECGs that occurred after the injections was the development of small Q waves in the six dogs in Group A that manifested clockwise initial forces in the frontal plane. The VCG performed in serial fashion may be more sensitive than the 12 lead ECG for detecting right ventricular inferior wall necrosis in the experimental animal. Application of these findings to the diagnosis of myocardial infarction in humans requires further investigation.