bluuebunny/crossref_metadata_2025 huggingface dataset:
Bare Metal Stents for Treatment of Extracranial Internal Carotid Artery Aneurysms
Authors: Welleweerd Janna C. , de Borst Gert Jan , de Groot Daphne , van Herwaarden Joost A. , Lo Rob T. H. , Moll Frans L.
Published: March 2015

Purpose: To examine the long-term outcomes of bare metal stent placement for exclusion of extracranial internal carotid artery (ICA) aneurysms. Methods: From 2006 to 2011, 7 consecutive symptomatic patients (4 men; mean age 52 years) with surgically inaccessible extracranial ICA aneurysms were treated with a bare stent at a single center. Patients received clopidogrel for 3 months after the procedure and aspirin for life. Clinical follow-up with duplex ultrasound and/or computed tomographic angiography was performed at 3, 6, and 12 months and yearly thereafter. Results: All procedures were technically successful; no neurological complications occurred. After 6 months, there was complete thrombosis of the aneurysm in all except one case. In this asymptomatic patient, the residual active flow was successfully obliterated by additional coil embolization. Over a mean follow-up of 57±22 months, all patients were alive and free of local or central neurological symptoms. All stents were patent, and thrombosis of the aneurysms was complete. Conclusion: In this small series, treatment of extracranial ICA aneurysms with a bare stent seems technically feasible and safe. All treated extracranial ICA aneurysms were excluded by primary intervention or secondary coil embolization.
Endoluminal Grafting of Abdominal Aortic Aneurysms: Causes of Failure and Their Prevention
Authors: May James , White Geoffrey H. , Yu Weiyun , Waugh Richard C. , McGahan Timothy , Stephen Michael S. , Harris John P.
Published: March 2015

Purpose:

The aim of this study was to analyze the causes of failure of endoluminal grafting for abdominal aortic aneurysms (AAA) and to put forward proposals for preventing these failures.

Methods:

Since May 1992, endoluminal repair of aneurysms was undertaken in 47 patients. Forty-three of these patients had AAAs and are the basis of this study. All procedures were nonurgent and were performed in the operating room with the patient draped for an open repair in the event of failed endoluminal repair. Radiographic guidance was used to pass the endografts into the aorta via a delivery sheath introduced through the femoral or iliac arteries. The configuration of the endografts was tubular (n = 28), tapered aortoiliac/aorto-femoral (n = 11), and bifurcated (n = 4).

Results:

Successful endoluminal repair was achieved in 34 of 43 (79%) patients. The remaining nine were terminated in favor of an open repair. The causes of failure were problems with access (2), balloon malfunction (1), stent dislodgment (3), graft thrombosis (1), and inability to deploy the contralateral limb of a bifurcated graft (2). All failed endoluminal repairs proceeded to successful open repair. There was no perioperative mortality in patients undergoing endoluminal repair or in those whose endoluminal repair was converted to open operation.

Conclusions:

The failures of endoluminal grafting have been analyzed. Methods of avoiding access problems, balloon malfunction, and stent dislodgment have been defined and recommendations made.
PTA and Thrombolysis in Leg Salvage
Authors: Motarjeme Amir
Published: March 2015

Purpose:

The goals of any treatment for ischemic vascular disease are to relieve pain, allow wound healing, and regain/maintain ambulatory abilities. To determine if endovascular therapy could accomplish these goals in patients with limbs at risk, we undertook a retrospective analysis of the results of percutaneous transluminal angioplasty (PTA) and thrombolysis in leg salvage.

Methods:

Over an 8-year period ending in 1993, 327 patients (209 males, 118 females) with limb-threatening ischemia (defined as one or more of the following: ischemic rest pain, ischemic ulceration, or gangrene) in 361 limbs were seen. These patients had an ante-brachial index ≤ 0.40 in nondiabetic patients and/or toe-brachial index ≤ 0.30 in diabetic patients. The patients were treated with thrombolysis and/or PTA according to standard techniques; intravascular stenting was used occasionally as required to treat PTA deficiencies or inadequate recanalization.

Results:

Among the 327 patients, 805 arteries and 25 thrombosed arterial grafts were treated. The arteries treated were: 6 aorta (0.75%), 75 iliac (9.3%), 34 common femoral (4.2%), 3 deep femoral (0.4%), 235 superficial femoral (29.2%), 219 popliteal (27.2%), 193 infrapopliteal (24.0%), and 40 pedal (5.0%). The patients were treated primarily with PTA (n = 307); urokinase thrombolysis (n = 99) and stents (n = 12) were used less frequently. Procedural success was 92.5. Patients were followed from 6 months to 8 years (mean 3 years). Eighty-three patients were retreated during this time. Of the 249 patients available for this follow-up, total salvage was achieved in 181 (72.7%). Nineteen patients (7.6%) underwent minor amputations (e.g., toes); 4 patients (1.6%) had transmetatarsal amputation. Fifteen patients (3.6%) had above-knee amputation despite successful recanalization. In all, 32 patients (8.8%) had the amputation level extended from above to below knee, bringing the total leg salvage rate to 82% (defined as patients able to ambulate without any prosthesis). Using life-table analysis, the 5-year survival rate was 71.

Conclusion:

This study shows that endovascular therapy for leg salvage is as effective as reconstructive vascular surgery in achieving wound healing and maintaining ambulation and has a more favorable 5-year survival rate.
Angiographic and Duplex Grading of Internal Carotid Stenosis: Can We Overcome the Confusion?
Authors: Nicolaides Andrew N. , Shifrin Edward G. , Bradbury Andrew , Dhanjil Surinder , Griffin Maura , Belcaro Gianni , Williams Michael
Published: March 2015

The stroke risk reduction benefit of surgical intervention in carotid occlusive disease has been validated in multicenter trials for various angiographically defined lesion severity categories. The two divergent angiographic grading methods used for internal carotid artery stenosis in these trials have caused confusion in the clinical application of their recommendations. Moreover, while today's highly accurate carotid duplex scanning can obviate the need for preoperative angiography in many cases, the duplex criteria must be tailored to achieve sufficiently reliable results on which therapeutic decisions can be made. This review offers a clarification of the discrepancies between the angiographic grading techniques and how their measurements of percent stenosis correlate to the duplex criteria needed to support the treatment decision-making process for carotid obliterative disease.
Endovascular Stent-Anchored Aortic Grafts: A Comparison between Self-Expanding and Balloon-Expandable Stents in Minipigs
Authors: Lindh Mats , Malina Martin , Ivancev Krasnodar , Brunkwall Jan , Lindblad Bengt
Published: March 2015

Purpose:

To study endovascular graft attachment with self-expanding Gianturco Z-stents and balloon-expanded Palmaz stents and the effect of these devices on the renal ostia.

Methods:

Ten stent-grafts were constructed, 5 with Gianturco Z-stents and 5 with Palmaz stents. The endografts were implanted under fluoroscopic guidance into the abdominal aorta of 10 pigs so that the uncovered portion of the proximal stent extended over the renal artery orifices. Distal aortic blood pressure and flow were measured before and after graft placement and 1 hour postprocedure. The aorta was then exposed surgically, and the central portion of the stent-graft was inspected through an aortotomy to assess perigraft leakage.

Results:

Stent-graft implantation was accurate and hemostatic in all cases, despite longitudinal folding of the graft due to oversizing. However, transverse folds produced pressure gradients (> 15 mmHg) between the ends of the graft in two cases. In another case, a pressure gradient resulted from partial thrombosis of the graft. In two cases, renal artery occlusion and thrombosis occurred due to coverage by the graft material. In two other animals, one of the renal arteries was entirely uncovered by a stent. The remaining 16 renal arteries were covered by the proximal stent but not the graft, as intended. One (6.25%) of these arteries thrombosed, but the remainder were grossly patent when the animals were sacrificed at 1 hour.

Conclusions:

Both Palmaz and Gianturco Z-stents produced hemostatic endovascular graft attachment, even in the presence of moderate graft oversizing. The risk of acute renal artery occlusion from juxtarenal stenting does not appear to be prohibitive, but longer term observations are needed.
Gasless Videoendoscopic Implantation of an Aortobifemoral Vascular Prosthesis via a Transperitoneal versus Extraperitoneal Approach: An Experimental Study
Authors: Bruns Christiane , Wolfgarten Bernd , Walter Michael , Pichlmaier Heinz , Koebke Jürgen
Published: March 2015

Purpose:

To report progress in the development of a new minimally invasive surgical technique for aortobifemoral grafting utilizing gasless videoendoscopy.

Methods:

In an experimental study, aortobifemoral Dacron vascular prostheses were implanted in 20 human cadavers using videoendoscopic techniques in both transperitoneal and extraperitoneal approaches. Rather than inducing pneumoperitoneum, the abdominal wall was elevated with an electrically powered lifting system.

Results:

Each approach was utilized in 10 cadavers for implantation of 20 aortobifemoral grafts under endoscopic guidance in a gasless field. Average operative time for the transperitoneal approach was 3.8 hours (range 3.0 to 5.5), slightly less than the average 4.1 hours (range 3.0 to 6.0) for the extraperitoneal access. Both access routes provided adequate visualization of the operative field.

Conclusions:

Advantages of gasless endoscopy include the use of conventional instruments and the potential benefits associated with a minimally invasive approach. Optical magnification facilitates suturing of the femoral anastomosis, improves examination of the vascular walls, and allows a more accurate suturing technique.
Endovascular Covered Stent Repair of an Intercostal Artery Patch Dehiscence from a Descending Thoracic Aortic Aneurysm Graft
Authors: Dorros Gerald , Avula Surendra , Fox Paul , Rhomberg Bernard , Werner Paul
Published: March 2015

Purpose:

To describe the use of endovascular techniques to repair a descending thoracic aortic pseudoaneurysm at a site of patch dehiscence.

Methods and Results:

A 63-year-old hypertensive, diabetic female with a 4-cm aneurysm in the descending thoracic aorta underwent surgical repair with a 35-mm Dacron graft. Dehiscence of the intercostal arterial patch produced a large, 6-cm-diameter pseudoaneurysm that extended into the left thoracic cavity. An endovascular repair was planned using a Dacron stent-graft. Despite induced hypotension and an exteriorized, stiff exchange wire to enhance control of the delivery balloon catheter, the initial attempt failed to close the suture line defect. A customized polytetrafluoroethylene-covered, balloon-expandable stent was successfully deployed using the original stent-graft as a landmark. At 6 months, the contrast-enhanced spiral computed tomographic scan showed patency of the stent-graft and resorption of the pseudoaneurysm.

Conclusions:

This communication describes the management of a surgical complication using balloon-expandable covered stents in contrast to either conventional surgery or self-expanding stent-grafts. Transesophageal ultrasound monitoring delineated the suture line leak, identified the position of the stent-grafts, and accurately demonstrated closure of the defect.
Sigmoid Sinus Thrombosis Associated with Internal Jugular Venous Occlusion: Direct Thrombolytic Treatment
Authors: Gurley Melissa B. , King Teresa S. , Tsai Fong Y.
Published: March 2015

Purpose:

To report our experience with transfemoral direct venous thrombolysis and angioplasty to treat central venous and dural sinus occlusion. The cases presented are rare examples of internal jugular occlusion associated with sigmoid sinus thrombosis.

Methods and Results:

Two middle-aged, symptomatic female patients were diagnosed with sigmoid sinus and internal jugular vein thrombosis. Venography was performed from a contralateral transfemoral approach, followed immediately by urokinase infusion directly to the occlusion using an intermittent “burst-bolus” technique. Successful thrombolysis of the sigmoid sinus and internal jugular vein was documented in both patients. In one case, a venous stenosis was treated with balloon angioplasty. Clinical signs and symptoms resolved in both patients.

Conclusions:

Occluded dural sinuses and central veins can be treated with direct administration of thrombolytic agents. When an underlying stenosis is identified, balloon dilation should be used to reduce the likelihood of recurrence.
Techniques for Endovascular Recanalization of Supra-Aortic Trunks
Authors: Criado Frank J. , Twena Mordechai
Published: March 2015

The supra-aortic arteries are no stranger to endovascular interventions. Since the 1980s, interventionists have been evaluating and refining the use of transluminal techniques for recanalizing stenotic and occlusive lesions in these large-bore, high-flow vessels. The authors present their methodologies for evaluating, selecting, and treating supra-aortic lesions with balloon angioplasty and stenting. Helpful suggestions are offered for optimizing the outcome of these endovascular approaches to atherosclerotic occlusive disease in the supra-aortic trunks.
Changing Aneurysmal Morphology after Endovascular Grafting: Relation to Leakage or Persistent Perfusion
Authors: Malina Martin , Ivancev Krasnodar , Chuter Timothy A.M. , Lindh Mats , Länne Toste , Lindblad Bengt , Brunkwall Jan , Risberg Bo
Published: March 2015

Purpose:

To relate changing abdominal aortic aneurysm (AAA) morphology after endovascular grafting to the presence of leakage, collateral perfusion, and other factors.

Methods:

Thirty-five patients who underwent successful AAA endovascular grafting were evaluated. Self-expanding Z-stents and Dacron grafts were applied in bifurcated and aortomonoiliac systems. Postoperative diameter changes were calculated from repeated spiral computed tomographic scans, angiograms, and ultrasonic phase-locked echo-tracking scans during a median 6-month follow-up (interquartile range [IQR] 3 to 12).

Results:

At 12 months, the diameters of completely excluded aneurysms had decreased 6 mm (IQR 2 to 11; p = 0.006). The proximal graft-anchoring stents had dilated 2 mm (IQR 0.5 to 3.3; p = 0.01). The aortic diameters immediately below the renal arteries but above the stents had not changed. Endoleakage and collateral perfusion (n = 13) were each associated with preserved aneurysm size and a 12 times higher risk of aneurysm dilation. After the leakage or the collateral perfusion had been treated, the aneurysm size decreased. Aneurysms with extensive intraluminal thrombi presented a reduced risk of leakage or perfusion.

Conclusions:

The diameters of endovascularly excluded AAAs decrease, except in cases of leakage or perfusion. Careful follow-up of patients with aortic endografts is necessary.
Intravascular Ultrasound: The Ultimate Tool for Abdominal Aortic Aneurysm Assessment and Endovascular Graft Delivery
Authors: White Rodney A. , Donayre Carlos , Kopchok George , Walot Irwin , Wilson Eric , deVirgilio Christian
Published: March 2015

Intravascular ultrasound (IVUS) imaging is a relatively new, rapidly evolving technology that enables precise catheter-based assessment of the dimensions and morphology of vascular structures and lesions. In extensive preclinical laboratory developmental studies and in clinical cases of endograft deployment for treatment of abdominal aortic aneurysms, we have found IVUS invaluable for determining key parameters of aortic morphology before and during interventions and for assessing the accuracy of deployment after device placement. By combining the IVUS data with information obtained from angiography, magnetic resonance imaging, and computed tomography (axial and three-dimensional reconstructions), we have been able to size devices and choose optimal fixation sites to prevent endoleaks and maintain luminal patency acutely and in the long term.
Successful Endoluminal Repair of Arterial Aneurysms by Wallstent Prosthesis and PTFE Graft: Preliminary Results with a New Technique
Authors: Krajcer Zvonimir , Diethrich Edward B.
Published: March 2015

Purpose:

To describe a new method of endovascular aneurysm exclusion using a Wallstent-PTFE vascular prosthesis in patients at high risk for surgery.

Methods and Results:

Two patients with significant comorbidities refused surgery in favor of endoluminal grafting for treatment of aneurysms in the abdominal aorta and popliteal artery, respectively. Both endovascular procedures were performed percutaneously with local anesthesia using a low-profile customized endograft constructed of thin-walled, predicted polytetrafluoroethylene (PTFE) graft mounted on a Wallstent. In both cases, the aneurysm was excluded from the arterial circulation; there were no postprocedural complications. Follow-up evaluation with appropriate imaging at 8 months (popliteal aneurysm) and 2 months (abdominal aneurysm) revealed no endoleaks.

Conclusions:

Our preliminary results indicate that the Wallstent-PTFE graft, with its smaller diameter and flexible design, offers significant advantages over currently available devices for repair of arterial aneurysms. This method obviates the need for general anesthesia or surgical exposure for arterial repair, which would increase the risk of the procedure in these patients.
Time-Related Alterations in Shape, Position, and Structure of Self-Expanding, Modular Aortic Stent-Grafts: A 4-year Single-Center Follow-up
Authors: Umscheid Thomas , Stelter Wolf J.
Published: March 2015

Purpose:

To report the nature and ramifications of structural and positional changes over time in tube and modular bifurcated aortic stent-grafts.

Methods:

Two hundred ninety-one patients received endovascular aortic grafts (primarily Stentor/Vanguard) between August 1994 and August 1998. Follow-up surveillance (clinical and laboratory examination, biplanar noncontrast radiography, and contrast-enhanced computed tomography) has been maintained on all patients for 4 years. Changes in the configuration and position of endografts have been noted and their sequelae charted.

Results:

Three types of endograft shape changes have been documented: mild — slight distortions visible on plain radiographs (n = 90, 31.0%), significant — angulations reaching 60° to 90° (n = 65, 22.3%), and severe — angulations ≥ 90° (n = 10, 3.4%). Changes in position never gave rise to late migration at the proximal attachment site, whereas at the distal ends, the endograft easily retracted from the iliac arteries (n = 8). Structural alterations (rupture of the stent frame, sutures, or fabric, and total graft disintegration) were more common in the original Stentor model. Shape, position, and structural alterations were mutually dependent and led to secondary endoleaks (n = 26) and graft limb thrombosis (n = 37). Late surgical conversion was necessary in 3 (1.0%) patients.

Conclusions:

Tortuosity of the native vessels is a source of complication in long-term follow-up just as it is during implantation. Given the late appearance of complications in this patient cohort, it would seem that the durability of an endograft cannot be evaluated with < 3 years of follow-up.
Influence of Age upon Complications of Carotid Artery Stenting
Authors: Chastain Hollace D. , Gomez Camilo R. , Iyer Sriram , Roubin Gary S. , Vitek Jiri J. , Terry John B. , Levine Ronald L. ,   UAB Neurovascular Angioplasty Team
Published: March 2015

Purpose:

To examine the impact of age upon the development of neurological and major systemic complications during or after carotid artery stenting.

Methods:

We reviewed the complications that occurred in patients undergoing elective carotid stent implantation between September 1994 and August 1996. The study population was then divided into 3 groups according to age: ≥ 80 (group A), 75 to 79 (group B), and ≤ 74 (group C) years. The rates of death, major and minor stroke, and myocardial infarction were compared among the groups, as well as with the rates reported by the major carotid endarterectomy (CEA) trials.

Results:

During the study period, 182 patients (216 vessels) were treated with carotid stenting. There were 19 (10.4%) complications: 1 (0.5%) death, 2 (1.1%) major strokes, 15 (8.2%) minor strokes, and 1 (0.5%) myocardial infarction. Neurological complications were clearly related to increased age with rates of 25.0% in group A versus 8.6% in group C (p = 0.042). The overall per patient rate of death or major stroke was 1.6% (1.4% per vessel).

Conclusions:

Increasing age has a negative impact on the rate of complications in carotid stent patients. However, the majority of those complications are minor. The relative roles of medical therapy, stenting, and CEA in patients > 80 years of age must await the results of randomized trials.
Long-term Follow-up of Endoluminal Grafting for Aneurysmal and Occlusive Disease in the Superficial Femoral Artery
Authors: Rodriguez-Lopez Julio A. , Soler Liliana , Werner Alan , Martinez Edgar , Papazoglou Konstantine , Diethrich Edward B.
Published: March 2015

Purpose:

To examine the long-term outcome of patients treated with endoluminal grafts (ELGs) for aneurysmal and occlusive disease in the femoropopliteal (FP) segment.

Methods:

ELGs of radially expandable polytetrafluoroethylene with terminal Palmaz stents were used to form intimal conduits to revascularize lengthy occlusive disease and exclude aneurysms in the FP segment. Patient records were reviewed retrospectively for outcome.

Results:

Fifty-five (98%) of 56 ELGs were placed successfully in 51 patients treated from August 1993 to February 1996. Over a mean 36-month follow-up, 28 (50%) ELGs occluded. Half of these failures reflected early technical difficulties. There were 11 (20%) stent stenoses, 6 in the proximal stent and 5 in the distal device. The majority of the graft failures were treated with endovascular techniques; however, FP bypass was required in 7 (25%) patients, while 2 (7%) were not treated. Life-table analysis demonstrated 46% primary and 68% secondary patency rates at 24 months. Among demographic and procedural variables, only previous dilation or stent procedures in the target artery was associated with failure (p < 0.0001).

Conclusions:

The prototype ELG used in this series demonstrated durability similar to conventional surgical therapy utilizing synthetic material. Endoluminal grafting of FP lesions may be a more durable alternative to classical bypass once devices and techniques are refined.
Acute Rupture of an Aortic False Aneurysm Treated with a Stent-Graft
Authors: Schönholz Claudio , Donnini Fabian , Naselli Gandolfo , Pocovi Antonio , Parodi Juan C.
Published: March 2015

Purpose:

To report the use of an aortic endograft to treat a ruptured false aneurysm at the anastomosis of an aortofemoral bypass graft.

Methods and Results:

A 68-year-old man with a 30-year-old aorto-right femoral bypass and multiple comorbidities was admitted to the hospital complaining of acute abdominal pain. Imaging identified a 60-mm ruptured aortic false aneurysm with associated retroperitoneal hematoma, a 9-cm right femoral false aneurysm, and a calcified 23-mm left common iliac aneurysm. Two slightly overlapping Vanguard straight stent-grafts were implanted in the aorta and left common iliac artery in an emergency procedure owing to the patient's high surgical risk. The anastomotic false aneurysm and the bypass were excluded. A left-to-right femorofemoral bypass was performed to re-establish flow to the right femoral artery with ligation of the external iliac artery. The patient recovered uneventfully. He remained well with a successful repair until his death of a myocardial infarction 6 months after the procedure.

Conclusions:

Endovascular grafting can be used successfully for the urgent treatment of aortic false aneurysm rupture.
Cognitive Screening in Persons With Chronic Diseases in Primary Care
Authors: Athilingam Ponrathi , Visovsky Constance , Elliott Amanda F. , Rogal Philip J.
Published: March 2015

An integrative literature review was performed to identify the challenges in current cognitive screening. The aim of the review was to serve as an evaluative resource to guide clinicians in the selection of the best available cognitive screening measures for early assessment of mild cognitive impairment (MCI) in people with chronic diseases. The review classified the available cognitive screening measures according to purpose, time to administer, and cognitive domains assessed as: 1) simple/ brief cognitive screening measures, 2) disease specific screening measures, 3) domain specific screening measures, 4) self-administered screening measures, and 5) technology-based screening measures. There is no single optimal cognitive measure for all patient populations and settings. Although disease specific cognitive screening measures are optimal, there is a lack of validated screening measures for many chronic diseases. Technology-based screening measure is a promising avenue for increasing the accessibility of cognitive screening. Future work should focus on translating available screening measures to mobile technology format to enhance the utility in busy primary care settings. Early cognitive screening in persons with chronic disease should enhance appropriate referrals for detailed neurocognitive examination and cognitive interventions to preserve and or minimize cognitive decline.
Effectiveness of Platelet-Rich Plasma to Enhance Healing of Diabetic Foot Ulcers in Patients With Concomitant Peripheral Arterial Disease and Critical Limb Ischemia
Authors: Kontopodis Nikolaos , Tavlas Emmanouhl , Papadopoulos George , Pantidis Dimitrios , Kafetzakis Alexandros , Chalkiadakis George , Ioannou Christos
Published: March 2015

We sought to investigate the effect of autologous platelet-rich plasma (PRP) on the healing rate of diabetic foot ulcers in patients with diabetes and concomitant peripheral arterial disease (PAD). Diabetic patients with foot ulceration presenting with PAD who were treated with local growth factors in a single center, during a 24-month period from May 2009 to April 2011, were retrospectively reviewed. Based on the severity of PAD, subjects were divided into groups A (Fontaine classification stages I, IIa, and IIb) and B (Fontaine classification stages III and IV), with those included in the latter being considered to suffer from critical limb ischemia (CLI). End points of the analysis were clinical improvement, limb salvage, and amputation rate. Outcome was compared between groups A and B. Overall, 72 patients were evaluated, 30 with CLI. Ulcer area reduction >50% was observed in 58/72 patients while reduction >90% was achieved in 52/72 patients. There were 14 (19%) major and minor amputations, whereas the limb salvage rate was 89%. This variable was significantly different between groups A and B (100% vs 73%, P < .001), as is rate of reduction in ulcer area >90% (83% vs 56%, P = .02). Reduction of ulcer area >50% was observed in the majority of patients in both groups (group A 86% vs group B 73%, P = .23). In conclusion, PRP could serve as a useful adjunct during management of diabetic foot ulcers even in diabetic patients with unreconstructable arterial disease.
Ingress
Authors: Majorek Marta , du Vall Marta
Published: March 2015

The thematic area covered by computer games is currently a widely discussed zone, analyzed from various research perspectives, yet then again, it still provides an interesting field for analysis. This domain remains quite dynamic, and this dynamic does not resemble slow transformations, which researchers in social studies have been previously used to, but it seems to be assuming the form of a multistage revolution. It is possible to outline several elementary issues representing the material of the analysis proposed within this text. In the first instance, the authors focus on the matter of change that occurs in thinking about what a computer truly is and then undertake an attempt to indicate the preliminary elements, which would determine the new character of games aimed at mobile computers. The Ingress game will constitute an example to depict the specification underlying this type of entertainment, as this will make it possible to delineate likely development scenarios for this particular area, especially based on the augmented reality concept and its influence on a modern approach toward entertainment that makes use of new mobile technologies.
Needs of caregivers in heart failure management: A qualitative study
Authors: Wingham Jennifer , Frost Julia , Britten Nicky , Jolly Kate , Greaves Colin , Abraham Charles , Dalal Hayes
Published: March 2015

Objectives

To identify the needs of caregivers supporting a person with heart failure and to inform the development of a caregiver resource to be used as part of a home-based self-management programme.

Methods

A qualitative study informed by thematic analysis involving 26 caregivers in individual interviews or a focus group.

Results

Three distinct aspects of caregiver support in heart failure management were identified. Firstly, caregivers identified needs about supporting management of heart failure including: coping with the variability of heart failure symptoms, what to do in an emergency, understanding and managing medicines, providing emotional support, promoting exercise and physical activity, providing personal care, living with a cardiac device and supporting depression management. Secondly, as they make the transition to becoming a caregiver, they need to develop skills to undertake difficult discussions about the role; communicate with health professionals; manage their own mental health, well-being and sleep; and manage home and work. Thirdly, caregivers require skills to engage social support, and voluntary and formal services while recognising that the long-term future is uncertain.

Discussion

The identification of the needs of caregiver has been used to inform the development of a home-based heart failure intervention facilitated by a trained health care practitioner.
The crystal structure of kiddcreekite solved using micro X-ray diffraction and the EPCryst program
Authors: Wenyuan Liu , Cheng Dong , Xiangping Gu , Yu Liu , Xiaoping Qiu , Yuchuan Chen
Published: March 2015

Abundant kiddcreekite grains were identified in the Zijinshan Cu-Au epithermal deposit in Fujian Province, China. The mineral occurs as polycrystalline grains, 5–300 μm in size, associated with colusite, enargite, stannoidite, mawsonite, vinciennite, hemusite, tennantite and wolframite in a predominantly covellite ore. Based on electron microprobe analysis, the empirical formula of the kiddcreekite is Cu6.2Sn0.97W0.95S7.83, without significant Se or Te contents. The crystal structure of kiddcreekite was solved using the direct-space method (EPCryst) from laboratory micro X-ray diffraction (μXRD) data and refined by the Rietveld method. The R values of the final Rietveld refinement were Rp = 9.06%, Rwp = 8.31%, RB = 3.16 and RF = 2.17%. Kiddcreekite has a cubic structure, space group F3m and lattice parameter a = 10.8178(3) Å (Z = 4, V = 1265.95(6) Å3). In the unit cell, W, Sn and Cu atoms occupy the 4a, 4c and 24f Wyckoff positions, respectively, and S atoms occupy two sets of 16e Wyckoff positions. The structure of kiddcreekite consists of stacked double MeS4 layers (giving a W–Sn–Cu tier and a Cu–vacancy tier) as in the sphalerite substructure. This study also demonstrates the possibility of using laboratory µXRD data coupled with the direct-space method to solve inorganic structures in cases where samples are too small for conventional powder and single-crystal diffraction.
The crystal structure of camerolaite and structural variation in the cyanotrichite family of merotypes
Authors: Mills S. J. , Christy A. G. , Schnyder C. , Favreau G. , Price J. R.
Published: March 2015

We present Raman data for camerolaite, cyanotrichite and carbonatecyanotrichite, and using synchrotron single-crystal X-ray diffraction have solved the structure of camerolaite from the Tistoulet Mine, Padern, Aude Department, France. Camerolaite crystallizes in space groupP1 with the unit-cell parameters:a= 6.3310(13) Å,b= 2.9130(6) Å,c= 10.727(2) Å, α = 93.77(3)°, β = 96.34(3)°, γ =79.03(3)º,V= 192.82(7) Å3andZ= ⅓, with respect to the ideal formula from the refinement, Cu6Al3(OH)18(H2O)2[Sb(OH)6](SO4). The crystal structure was solved toR1= 0.0890 for all 1875 observed reflections [Fo> 4σFo] and 0.0946 for all 2019 unique reflections. ThePcell has been transformed into aC-centred cell that aids comparison with that of the structurally related khaidarkanite byaC= 2aP–bP, giving parametersa= 12.441(3),b= 2.9130(6),c= 10.727(2) Å, α = 93.77(3), β = 95.57(3), γ = 92.32(3)º andZ= ⅔ in C1. Edge-sharing octahedral ribbons Cu2Al(O,OH,H2O)8form hydrogen-bonded layers || (001), as in khaidarkanite. The partially occupied interlayer Sb and S sites of the average structure are in octahedral and tetrahedral coordination by oxygen, respectively. They cannot be occupied simultaneously, which leads to regular alternation of [Sb(OH)6]–and SO42–groups in rods ||y, resulting in local tripling of the periodicity alongyfor the Sb(OH)6–SO4rods. Thus, camerolaite has a ‘host–guest’ structure in which an invariant host module (layers of Cu–Al ribbons) has embedded rod-like guest modules with a longer periodicity. Coupling between the phases of these rods is only short-range, resulting in diffuse X-ray scattering rather than sharp superstructure reflections. Similar disorder is known for parnauite, and is deduced for other members of the cyanotrichite group (cyanotrichite, carbonatecyanotrichite and khaidarkanite). Group members all share the Cu–Al ribbon module but have interlayer rods of different compositions and topologies; thus, they form a merotypic family. The low symmetry of the camerolaite average structure suggests other possibilities for structure variation in the group, which are discussed.
The Piteiras emerald mine, Minas Gerais, Brazil: fluid-inclusion and gemmological perspectives
Authors: Lynch E. P. , Costanzo A. , Feely M. , Blamey N. J. F. , Pironon J. , Lavin P.
Published: March 2015

New fluid inclusion analyses using a range of analytical techniques including quadropole mass spectrometric analyses coupled with gemmological investigations were conducted on rough and gemquality faceted emeralds from the Piteiras Mine, Minas Gerais, Brazil. These data complement those of Rondeau et al. (2003) who also presented analyses of the Piteiras emeralds. Emeralds are found typically as euhedral-to-anhedral crystals disseminated in biotite-phlogopite schist and range from 0.5 to 50 mm long. Emerald mineralization is associated closely with alkaline metasomatized pegmatite bodies, quartz boudin and veins, and talc-chlorite bands. Four types of fluid inclusions are recognized in the emeralds. These include aqueous brine and aqueous carbonic varieties containing one or two liquid phases, along with gas bubbles and/or solid crystals (e.g. carbonates). Primary fluid inclusions in emeralds record salinities of ~4–24 eq. wt.% NaCl and minimum trapping temperatures from ~350 to 480ºC. Combined microthermometry, Raman spectroscopy and crush-leach gas analyses indicate that the mineralizing fluid was an aqueous carbonic brine enriched in reduced volatile species such as CH4, N2, H2S and alkanes. With respect to their optical properties (RI ε = 1.573–1.580; RI ω = 1.580–1.588; birefringence = 0.006–0.008) and specific gravity (2.65–2.78), the Piteiras emeralds fall within the expected range for metasomatic, schist-hosted emeralds.
Synthetic norsethite, BaMg(CO3)2: revised crystal structure, thermal behaviour and displacive phase transition
Authors: Effenberger H. , Pippinger T. , Libowitzky E. , Lengauer C. L. , Miletich R.
Published: March 2015

The crystal structure of synthetic BaMg(CO3)2whose mineral name is norsethite was re-investigated by single-crystal X-ray diffraction. Complementaryin situhigh- and low-temperature studies by means of vibrational spectroscopy (Raman, IR), powder X-ray diffraction techniques and thermal analyses were performed. Diffraction images (298 K) revealed weak superstructure reflections caused by the displacement of the O atoms in the earlier consideredRmstructure model (a = 5.0212(9), cnew= 2 cold= 33.581(6) Å ,Rc, Z = 6, R1 = 0.011, sinθ/λ < 0.99 Å–1). Thermal analyses reveal decarbonatization in two decomposition steps above 750 K, and the heat-flow curves (difference scanning calorimetry) give clear evidence of a weak and reversible endothermal change at 343±1 K. This agrees with a discontinuity in the IR and single-crystal Raman spectra. The changing trend of thec/aratio supports this discontinuity indicating a temperature-induced structural transition in the range between 343 and 373 K. As the change of the unit-cell volume is almost linear, the character of the transition is apparently second order and matches the mechanism of a subtle displacement of the oxygen atom position. The apparent instability of theRcstructure is also evidenced by the remarkably larger anisotropic displacement of the oxygen atom.
High-pressure synthesis and application of a 13C diamond pressure sensor for experiments in a hydrothermal diamond anvil cell
Authors: Chertkova Nadezda , Yamashita Shigeru , Ito Eiji , Shimojuku Akira
Published: March 2015

Polycrystalline, cubic 13C diamond was synthesized from amorphous carbon in the Kawai-type multianvil apparatus at 21 GPa and at a temperature greater than 2350ºC. The polycrystalline diamond was homogeneous with a small grain size (10–20 μm) and a sharp Raman peak, and thereby was suitable as a pressure sensor for the experiments in a hydrothermal diamond anvil cell. Pressure- and temperature-dependence of the Raman shift of the synthesized 13C diamond was investigated in situ at simultaneous high pressures and high temperatures in the hydrothermal diamond anvil cell, using the ruby fluorescence line, quartz Raman shift and H2O phase transitions as pressure references. It was observed that the frequency shift with pressure is independent of temperature and vice versa up to 500ºC and 4.2 GPa. The present study indicates that the 13C diamond Raman shift can be used for pressure determination with an accuracy better than ±0.3 GPa under the conditions examined.
Unique thallium mineralization in the fumaroles of Tolbachik volcano, Kamchatka Peninsula, Russia. III. Evdokimovite, Tl4(VO)3(SO4)5(H2O)5
Authors: Siidra Oleg I. , Vergasova Lidiya P. , Kretser Yuri L. , Polekhovsky Yuri S. , Filatov Stanislav K. , Krivovichev Sergey V.
Published: March 2015

Evdokimovite, ideally Tl4(VO)3(SO4)5(H2O)5, was found in a fumarole of the 1st cinder cone of the North Breach of the Great Fissure Tolbachik volcano eruption of 1975–1976, Kamchatka Peninsula, Russia. Evdokimovite occurs as thin, colourless needles up to 0.09 mm long associated with shcherbinaite, pauflerite, bobjonesite, markhininite, karpovite and microcrystalline Mg, Al, Fe and Na sulfates. Evdokimovite is monoclinic, P21/n, a = 6.2958(14), b = 10.110(2), c = 39.426(11) Å , β = 90.347(6)º, V = 2509.4(10) Å3 and Z = 4 (from single-crystal diffraction data). The eight strongest lines of the powder X-ray diffraction pattern are (I/d/hkl): 57/9.793/011, 100/8.014/013, 26/6.580/006, 19/ 4.011/026, 29/3.621/118, 44/3.522/125, 19/3.010/036, 21/2.974/212. Chemical composition determined by the electron microprobe analysis is (wt.%): Tl2O 55.40, VO2 14.92, SO3 25.83, H2O 5.75, total 101.90. The empirical formula for evdokimovite calculated on the basis of (Tl + V + S) = 12 a.p.f.u. is Tl4.10V2.83S5.07H10.00O27.94. The simplified formula is Tl4(VO)3(SO4)5(H2O)5. The crystal structure was solved by direct methods and refined to R1 = 0.11 on the basis of 3660 independent observed reflections. V4+O6 octahedra and SO4 tetrahedra share common corners to form two types of vanadyl-sulfate chains, [(VO)(H2O)2(SO4)2]2– and [(VO)2(H2O)3(SO4)3]2–. Thallium atoms are located in between the chains. The structure can be described as a stacking of layers of two types, A and B. The A layer contains [(VO)2(H2O)3(SO4)3]2– chains and the Tl2 and Tl3 atoms, whereas the B layer contains [(VO)(H2O)2(SO4)2]2– chains and the Tl1 atoms. Stacking of the layers can be described as ...A’*BAA’B*A*..., where A and A’ denote A layers with opposite orientations of the [(VO)2(H2O)3(SO4)3]2– chains, and the A* and B* layers are rotated by 180º relative to the A and B layers, respectively. [(VO)2(H2O)3(SO4)3]2– chains are modulated and are arranged to form elliptical tunnels hosting disordered Tl(4), Tl(4A) and Tl(4B) sites. The new mineral is named in honour of Professor Mikhail Dmitrievich Evdokimov (1940–2010), formerly of the Department of Mineralogy, St Petersburg State University, for his contributions to mineralogy and petrology, and especially for teaching mineralogy to several generations of students at the University. Evdokimovite is the most complex V4+ sulfate known to date with structural information amounting to 1130 bits per unit cell, which places evdokimovite among minerals with the complexity of the vesuvianite group.
Crystal structure and revised chemical formula for burckhardtite, Pb2(Fe3+Te6+)[AlSi3O8]O6: a double-sheet silicate with intercalated phyllotellurate layers
Authors: Christy Andrew G. , Kampf Anthony R. , Mills Stuart J. , Housley Robert M. , Thorne Brent
Published: March 2015

The crystal structure of burckhardite from the type locality, Moctezuma, Sonora, Mexico, has been refined to R1 = 0.0362 and wR2 = 0.0370 for 215 reflections with I > 2σ(I). Burckhardtite is trigonal, space group P1m, with the unit-cell parameters a = 5.2566(5) Å , c = 13.0221(10) Å , V = 311.62(5) Å3 and Z = 1 for the ideal formula unit Pb2(Fe3+Te6+)[AlSi3O8]O6. There is no long-range order of (Fe3+, Te6+) or (Al3+, Si4+). New microprobe data were used to estimate site scattering factors, and Raman spectroscopic data showed no evidence of O–H stretching bands. Burckhardtite is not closely related to the micas, as supposed previously, but is a double-sheet silicate in which the aluminosilicate anion resembles that of minerals such as cymrite and kampfite. The [(Fe3+Te6+)O6]3– part of the structure is not bonded directly to the aluminosilicate layer, but forms a discrete anionic phyllotellurate layer that alternates with the [AlSi3O8]– double sheets. Similar phyllotellurate layers are known from several synthetic phases. In burckhardtite, Pb2+ cations intercalate between phyllosilicate and phyllotellurate layers, forming a Pb2[FeTeO6] module that is topologically similar to a slab of the structure of rosiaite, Pb[Sb2O6]. The crystal symmetry, structure, classification as a double-sheet silicate and chemical formula, including the determination of the 6+ valence of Te and absence of essential H2O, are all new findings for the mineral.
Thymic expression of a T-cell receptor targeting a tumor-associated antigen coexpressed in the thymus induces T-ALL
Authors: Cui Yongzhi , Onozawa Masahiro , Garber Haven R. , Samsel Leigh , Wang Ziyao , McCoy J. Philip , Burkett Sandra , Wu Xiaolin , Aplan Peter D. , Mackall Crystal L.
Published: March 2015

Key Points

Thymocyte signaling via a transgenic survivin-reactive TCR induced T-ALL with 100% penetrance. Thymic expression of signaling receptors targeting TAAs coexpressed in the thymus poses a risk for leukemogenesis.
Arsenic trioxide and all-trans retinoic acid target NPM1 mutant oncoprotein levels and induce apoptosis in NPM1-mutated AML cells
Authors: Martelli Maria Paola , Gionfriddo Ilaria , Mezzasoma Federica , Milano Francesca , Pierangeli Sara , Mulas Floriana , Pacini Roberta , Tabarrini Alessia , Pettirossi Valentina , Rossi Roberta , Vetro Calogero , Brunetti Lorenzo , Sportoletti Paolo , Tiacci Enrico , Di Raimondo Francesco , Falini Brunangelo
Published: March 2015

Key Points

ATRA and ATO affect NPM1 protein levels in AML cells and induce cell growth inhibition and apoptosis. AML cells with mutated NPM1 respond to ATRA/ATO, and this might be exploited therapeutically.
Energy balance and fitness in adult survivors of childhood acute lymphoblastic leukemia
Authors: Ness Kirsten K. , DeLany James P. , Kaste Sue C. , Mulrooney Daniel A. , Pui Ching-Hon , Chemaitilly Wassim , Karlage Robyn E. , Lanctot Jennifer Q. , Howell Carrie R. , Lu Lu , Srivastava Deo Kumar , Robison Leslie L. , Hudson Melissa M.
Published: March 2015

Key Points

Elimination of cranial radiation from therapy for childhood acute lymphoblastic leukemia has improved body-composition outcomes. Survivors of childhood acute lymphoblastic leukemia treated without cranial radiation remain at risk for impaired fitness.
Unexpected death within 72 hours of emergency department visit: were those deaths preventable?
Authors: Goulet Hélène , Guerand Victor , Bloom Benjamin , Martel Patricia , Aegerter Philippe , Casalino Enrique , Riou Bruno , Freund Yonathan
Published: March 2015

Introduction

We aimed to determine the rate of preventable death in patients who died early and unexpectedly following hospital admission from the emergency department (ED).

Methods

We conducted a retrospective multicenter study in four centers from the Paris metropolitan area. Inclusion criteria were medical patients who died in hospital within 72 hours of ED attendance and were not admitted to the intensive care unit (unexpected death). Exclusion criteria were limitations of care determined by treating physicians. The existence of a limitation of care decision was adjudicated by two independent chart abstractors. Preventable death was defined as death occurring as a result of medical error. For each selected patient with unexpected death, charts were examined for medical errors and rated on a 1 to 5 preventability scale (from very unlikely to very likely) for the preventability of the death. The primary endpoint was the likely preventable death, rated as 4 or 5 on the preventability scale.

Results

We retrieved 555 charts; 47 unexpected deaths were analysed; 24 (51%) were considered as preventable. There was a median number of medical errors of two. The most common process breakdowns were incorrect choice of treatment (47% of patients) and failure to order appropriate diagnostic tests (38% of patients). The most common medical error was a severe delay or absence of recommended treatment for severe sepsis, which occurred in 10 (42%) patients.

Conclusions

In our sample, more than half of unexpected deaths are related to a medical error, and could have been prevented.