New Insight into Nanoscale Identification of the Polar Axis Direction in Organic Ferroelectric Films

Ferroelectric poly(vinylidene fluoride-co-trifluoroethylene) [P(VDF-co-TrFE)] thin films have been deposited by spin-coating onto the Bi0.5Na0.5TiO3(BNT)/LNO/SiO2/Si heterostructure. The copolymer microstructure investigated by using grazing-incidence wide-angle X-ray diffraction (GIWAXD) and deduced from the (200)/(110) reflections demonstrates that the b-axis in the P(VDF-co-TrFE) orthorhombic unit cell is either in the plane or out of the plane, depending on the face-on or on the two types of edge-on (called I and II) lamellar structures locally identified by atomic force microscopy (AFM). For edge-on I lamellae regions, the electroactivity (dzzeff ∼ -50.3 pm/V) is found to be twice as high as that measured for both edge-on II or face-on crystalline domains, as probed by piezoresponse force microscopy (PFM). This result is directly correlated to the direction of the ferroelectric polarization vector in the P(VDF-co-TrFE) orthorhombic cell: larger nanoscale piezoactivity is related to the b-axis which lies along the normal to the substrate plane in the case of the edge-on I domains. Here, the ability to thoroughly gain access to the as-grown polar axis direction within the edge-on crystal lamellae of the ferroelectric organic layers is evidenced by combining the nanometric resolution of the PFM technique with a statistical approach based on its spectroscopic tool. By the gathering of information at the nanoscale, two orientations for the polar b-axis are identified in edge-on lamellar structures. These findings contribute to a better understanding of the structure-property relationships in P(VDF-co-TrFE) films, which is a key issue for the design of future advanced organic electronic devices.

Sleep Medication in Older Adults: Identifying the Need for Support by a Community Pharmacist

Many older adults take benzodiazepines and sedative-hypnotics for the treatment of sleep disorders. With a view to considering the possible discontinuation of hypnotics, the objectives of the present study were to describe bedtime habits and sleep patterns in older adults and to identify the sleep medications taken. An expert group developed a structured interview guide for assessing the patients’ bedtime habits, sleep patterns, and medications. During an internship in a community pharmacy, 103 sixth-year pharmacy students conducted around 10 interviews each with older adults (aged 65 or over) complaining of sleep disorders and taking at least one of the following medications: benzodiazepines, benzodiazepine derivatives (“Z-drugs”), antihistamines, and melatonin. A prospective, observational study was carried out from 4 January to 30 June 2016. The pharmacy students performed 960 interviews (with 330 men and 630 women; mean ± standard deviation age: 75.1 ± 8.8). The most commonly taken hypnotics were the Z-drugs zolpidem (n = 465, 48%) and zopiclone (n = 259, 27%). The vast majority of patients (n = 768, 80%) had only ever taken a single hypnotic medication. The median [interquartile range] prescription duration was 120 (48–180) months. About 75% (n = 696) of the patients had at least 1 poor sleep habit, and over 41% (n = 374) had 2 or more poor sleep habits. A total of 742 of the patients (77%) reported getting up at night—mainly due to nycturia (n = 481, 51%). Further, 330 of the patients (35%) stated that they were keen to discontinue their medication, of which 96 (29%) authorized the pharmacist to contact their family physician and discuss discontinuation. In France, pharmacy students and supervising community pharmacists can identify problems related to sleep disorders by asking simple questions about the patient’s sleep patterns. Together with family physicians, community pharmacists can encourage patients to discuss their hypnotic medications.

Does hip or knee joint replacement decrease chances to complete an ultra-trail race? Study in participants at the Ultra-Trail du Mont Blanc®

INTRODUCTION

The number of patients with hip or knee joint replacements is increasing. Some of these patients want to practice sport, including in high-impact sports such as ultra-trails. Is the proportion of drop-out higher among runners after a hip or knee replacement? What are the symptoms of these patients?

HYPOTHESIS

Hip or knee joint replacements are associated with a higher drop-out rate during an ultra-trail.

MATERIAL AND METHODS

We conducted a monocentric retrospective epidemiological study. A questionnaire translated into French, English and Spanish were sent to all runners registered for one or more of the 5 races of the 2015 to 2017 Ultra-Trail du Mont-Blanc® (UTMB®) editions. There were no exclusion criteria. The drop-out rate of patients who responded to the questionnaire was calculated among patients with and without hip or knee joint replacement. Specific symptoms related to these joint replacements were identified before, during and after the race.

RESULTS

Out of the 24,855 participants having run at least one of the 3 editions, 2,469 responded. Some of them ran several races: these 2469 runners were on 3171 start lines and 2548 finish lines (drop-out rate of 19.6%). Among these 2469 runners, 18 had hip and/or knee replacement and were on 27 start lines and 17 finish lines (drop-out rate of 37%). The race was finished by 3 of the 6 runners with a total hip arthroplasty (THA), all of the 8 runners with a hip resurfacing arthroplasty (HRA) and 3 of the 4 runners with a total knee arthroplasty (TKA). Among runners with THA, pubalgia or groin pain was described by one of them before the race, 3 during the race and 2 after the race. Among runners with HRA, pygalgia or groin pain was described by 2 of them during the race. As for the TKA, there was no specific symptom. No answering runner had a unicompartmental knee prosthesis.

DISCUSSION

Running ultra-trail is possible after a hip or knee joint replacement. All of the 8 runners with HRA finished the race. We may remain cautious about the long-term survival of prostheses.

LEVEL OF PROOF

IV; monocentric retrospective epidemiological study.

Polypharmacy in older patients: identifying the need for support by a community pharmacist

BACKGROUND

The community pharmacist is a key player in medication reviews of older outpatients. However, it is not always clear which individuals require a medication review. The objective of the present study was to identify high-priority older patients for intervention by a community pharmacist.

METHODS

As part of their final-year placement in a community pharmacy, pharmacy students conducted 10 interviews each with older adults (aged 65 or over) taking at least five medications daily. The student interviewer also offered to examine the patient's home medicine cabinet. An interview guide was developed by an expert group to assess the difficulties in managing and taking medications encountered by older patients.

RESULTS

The 141 students interviewed a total of 1370 patients (mean age: 81.5; mean number of medications taken daily: 9.3). Of the 1370 interviews, 743 (54.2%) were performed in the patient's home, and thus also included an examination of the home medicine cabinet. Adverse events were reported by 566 (42.0%) patients. A total of 378 patients (27.6%) reported difficulties in preparing, administering and/or swallowing medications. The inspections of medicine cabinets identified a variety of shortcomings: poorly located cabinets (in 15.0% of inspections), medication storage problems (21.7%), expired medications (40.7%), potentially inappropriate medications (15.0%), several different generic versions of the same drug (19.9%), and redundant medications (20.4%).

CONCLUSIONS

In a community pharmacy setting, high-priority older patients for intervention by a community pharmacist can be identified by asking simple questions about difficulties in managing, administering, taking or storing medications.

Nanoscale Investigations of α- and γ-Crystal Phases in PVDF-Based Nanocomposites

The impact of carbon nanotube (CNT) incorporation into semicrystalline poly(vinylidene fluoride), PVDF, was investigated at both the macro and nanoscales. A special effort was devoted to probe the local morphology and the mechanical, ferroelectric, piezoelectric, and electrical conductivity response by means of atomic force microscopy. Incorporation of CNTs mainly induces the development of the polar γ-phase, and as a consequence, the coexistence of the γ-phase with the most stable nonpolar α-phase is observed. A maximum γ-phase content is reached at 0.7 wt % CNT loading. The spherulitic morphology of the PVDF α-phase is assessed, in conjunction with the lack of any ferroelectric response, while the presence of the polar γ-phase is confirmed, owing to clear piezoresponse signals. Local piezoelectric measurements on γ-phase domains yield a maximum effective coefficient | d₃₃| ≈ 13 pm/V, thus underlining the potential for applications of such functional PVDF-based nanocomposites in advanced piezoelectric devices. An increase in macroscopic conductivity with CNT content is observed, with a percolation threshold achieved for a composition close to 0.7 wt %. Nanoscale investigation of the electrical conductivity confirms the presence of some infinite CNT cluster homogeneously distributed over the surface. The macroscopic viscoelastic behavior of the composite reflects the reinforcing effect of CNTs, while the nanomechanical characterization yields a local contact modulus of the γ-phase domains larger than that of its α-phase counterpart, in agreement with the fact that the CNTs act as γ-phase promoters and subsequently reinforce the γ-domains.

Influence of fatty chain length and starch composition on structure and properties of fully substituted fatty acid starch esters

A series of almost fully substituted Fatty Acid Starch Esters (FASEs) has been obtained in a homogeneous LiCl/DMAc medium by grafting octanoyl (C8), lauroyl (C12) and palmitoyl (C16) chlorides onto 3 starch species: Amylo-Maize, Potato and Waxy Maize. Structure-property relationships of FASEs are investigated as a function of both fatty acid chain length and amylose/amylopectin ratio of the starch. The structural study has revealed a layered type organization in which starch chain planes are separated by fatty chains. The latter are interpenetrated and/or tilted for FASE-C16 whatever the origin of the starch is, and fatty chains partially crystallizes into a structure with hexagonal symmetry. FASEs with C8 and C12 side chains are totally amorphous. The mechanical behavior of FASEs is shown to depend on both side chain length and amylose/amylopectin ratio, and an increase in material ductility is observed at increasing amylose content for C8 and C12 side chains.

Highly efficient ring-opening reaction of azlactone-based copolymer platforms for the design of functionalized materials

Azlactone-based homopolymers and copolymers were successfully synthesized using the reversible addition-fragmentation chain transfer (RAFT) process. The functional monomer 2-styryl-4,4-dimethylazlactone (SDA) was first homopolymerized in bulk then copolymerized with styrene, leading to (co)polymers with low polydispersity indices (PDI = 1.10-1.20). The reactive azlactone rings, located along the backbone of the copolymers were subjected to highly efficient ring-opening reactions with functionalized primary amine derivatives incorporating a fluorescent (naphthalene) or an electrochemical (ferrocene) probes, a biological fragment (glutathione), a sugar unit (β-cyclodextrin), or an oligomeric fluorinated moiety, leading to materials with various interesting properties.

A new vascular sealant (Sealgel) to achieve rapid hemostasis after percutaneous angioplasty in anticoagulated patients: clinical feasibility and preliminary results

The aim of this study was to assess the feasibility of a new vascular sealant (Sealgel) to provide rapid hemostasis in anticoagulated patients after percutaneous transluminal angioplasty (PTA). Sealgel was designed with ancrod (10 mg) and tranexamic acid (80 mg) dissolved in a hyaluronic acid gel (3 ml). Fifty anticoagulated patients (heparin, aspirin, ticlopidin) who underwent PTA of coronary artery were enrolled in the study. Sealgel (3 ml) was delivered under manual compression through a 9-F cannula at the arterial puncture site after the introducer sheath removal at the end of PTA procedure. Hemostasis time as well as complications were recorded. Sealgel was successfully delivered in 98 % of patients. Hemostasis occurred within 15 mn of manual compression in 82 % of patients, within 25 mn in 98 %, and failed in 1 patient (2 %). Hematoma (6-cm diameter) was observed in 1 patient and late bleeding in another one. There were no clinical signs of embolism, inflammatory swelling, local infection, vascular fistula, or pseudoaneurysm. No surgery or blood transfusion was required. Sealgel application after PTA in anticoagulated patient is feasible and secure. Preliminary results suggest that the Sealgel brought about rapid hemostasis; however further studies are needed to determine its clinical efficacy.

Treatment of an ilio-caval thrombosis by mechanical thrombolysis

In proximal deep vein thrombosis, thrombolytic treatment is more effective than heparin from a recanalization point of view but with a failure rate of 20%. We describe an interventional therapeutic procedure that may be effective in these cases. Mechanical thrombolysis with the thrombolizer (Angiocor, Lille Hellemmes, France) has been tried in 2 cases of deep vein thrombosis, when systemic thrombolysis alone had failed.

Inoue balloon usefulness in case of failure to stabilize bifoil catheter balloons during percutaneous mitral valvotomy

A new bifoil balloon catheter has been used in the last 120 percutaneous mitral valvotomies carried out in our institution. The shaft segment between the two balloons of the bifoil catheter has been adjusted to the guide-wire diameter, allowing its introduction through a 14F sheath. This thinner shaft does not always offer enough back up to the balloons during inflation. An Inoue balloon replaced an unstable bifoil balloon in 5 cases of mitral dilatation failure due to balloon instability, regularly providing firm stability until full balloon inflation.

Peripheral laser angioplasty with sapphire tip

To improve the result of peripheral laser recanalization (less perforation with wider tunnels of vaporization), we used the technique of sapphire laser angioplasty. A Nd:YAG laser with continuous emission was connected to a catheter with a 600 mum fiber and a sapphire probe to its extremity (1.8-3 mm in diameter). Treatment was performed on 127 patients with severe stenosis or occlusion of peripheral arteries (iliac, femoral, or popliteal arteries). Recanalization was obtained in 102 cases (80%) and was further embellished by balloon dilatation. The rate of success decreased proportionally with the length of occlusions (93% for 3 cm, 33% for 15 cm and more). Most failures were due to wall perforation or wall entry of the probe; passage of the sapphire tip was rarely blocked by the occlusion. At follow-up, 26.4% of arteries were reoccluded after 2 months.

IN CONCLUSION

laser angioplasty with a sapphire tip can totally recanalize occluded arteries with low rate of failure and complications.

Percutaneous transvenous caval interruption with the "LGM" filter: early results of a multicenter trial

From September 1985 to December 1986, 100 patients undergoing percutaneous placement of a transvenous "LGM" caval filter were included in a multicenter prospective trial. Peripheral venograms completed by pulmonary arteriography or scintigraphy were obtained for all patients. Eighty-five patients had experienced pulmonary embolism, 59 had iliocaval thrombosis, while 40 had venous thrombosis confined to the lower limbs. In two instances, insertion or passage of the catheter was impossible. Ninety-eight "LGM" filters were placed percutaneously through the internal jugular vein, 82 of which were correctly positioned in the infrarenal inferior vena cava. Eight filters were positioned with a tilt of more than 15 degrees with respect to the vertical axis, five failed to open correctly, and three were incompletely open and tilted. No postoperative deaths were observed; there were two recurrent embolisms, and seven caval thromboses occurred during the year that followed insertion of the filter. The "user-friendliness" and efficacy of this percutaneous filter makes it a treatment of choice in the partial interruption of the inferior vena cava.

[Treatment of femoro-popliteal thrombosis by peripheral angioplasty. Value of the laser]

In a series of 197 dilatations of the peripheral arteries performed over a 5-year period (1980-1985), 38 concerned complete thrombosis (less than 12 cm long) of the femoral and popliteal arteries. While in patients with femoral stenosis (n = 49) the primary success rate was 95 p. 100 with an annual recurrence rate of 8 p. 100, in patients with complete thrombosis the primary success rate was only 52 p. 100, and the recurrence rate was 30 p. 100 at 6 months. Such results would justify the use of new therapeutic methods. Percutaneous laser thermal angioplasty is now being evaluated, and it appears that the primary success rate is considerably increased by combined laser and balloon angioplasty. Recurrences raise a much more complex problem and require a multifactorial management with improved dilatation techniques, anti-platelet or anticoagulant treatment, abstention from smoking and close surveillance.

[Early detection of myocardial alterations in mitral insufficiency with the angiotensin test]

Left ventricular function was assessed at rest and after increasing systemic arterial resistance by angiotensin in 40 patients with isolated mitral insufficiency. Angiotensin was administered intravenously at a dose of 0,4 micrograms/mn until the systolic blood pressure rose by at least 30 mm Hg. Left ventricular and aortic pressures, cardiac index and left ventriculography in the 30 degree right anterior oblique projection (50 frames per second) were recorded before and during angiotensin infusion. The mean rise in systolic left ventricular pressure was 40 +/- 2,8 mm Hg; the heart rate increased slightly but significantly; left ventricular and diastolic pressure rose from 12,0 +/- 1,0 to 24,0 +/- 1,2 mmHg. The systolic index (Fick's method) was significantly decreased (37 +/- 1,6 ml/m2 to 26 +/- 1,6 ml/m2) though the angiographic systolic index remained unchanged. This is explained by an increase in the regurgitant fraction (51 +/- 2,5% ao 65 +/- 3%). The end diastolic volume index was unchanged; the ejection fraction was significantly decreased. The resting hemodynamic status was only slightly disturbed in 29 patients (mean capillary pressure less than 15 mm Hg, 8,8 +/- 0,52 mmHg). The left ventricular function curves with angiotensin distinguished two groups of patients: Group A (20 patients) with left ventricular dysfunction induced by angiotensin, Group B (9 patients) who maintained the systolic index despite the increase in left ventricular end diastolic pressure. These results suggest that the angiotensin test may be useful for detecting early left ventricular dysfunction in patients with isolated mitral insufficiency and virtually normal resting hemodynamic parameters.

Coronary arteriography in acute transmural myocardial infarction

Coronary arteriography was performed 16 +/- 3 days (range 7 to 21 days) in 106 patients with acute transmural myocardial infarction (61 posterior infarct, 45 anterior infarct). Coronary arteriography was performed without serious complications. Only 44% of patients with anterior infarct had total occlusion of the left anterior descending artery while a significant stenosis of the vessel was observed in the others -27% had a single vessel disease, 49% had two lesions and 22% had three lesions; one patient had angiographically normal coronary arteries. Among the patients with posterior infarction, 21% had one vessel disease and double or triple lesions accounted for 39% of each. Sixty per cent of patients with anterior infarction and 45% with posterior infarction had no collateral vessels. In the others patients collateral circulation had a protective effect only in anterior infarction. Age has no effect on the distribution and number of lesions nor on the development of a collateral circulation. The location and severity of the lesions were not different in patients who presented with arrythmias and those who did not.

Left ventricular compliance in acute transmural myocardial infarction in man

130 patients with recent transmural myocardial infarction were studied in order to evaluate changes in left ventricular compliance. Left heart catheterization and cineangiographic left ventriculography were performed. The modulus of chamber stiffness (K) was determined from the slope of the linear relation between volume stiffness (dP/dv) and pressure; the modulus of muscle stiffness was evaluated by the Laird index (asymptotic slope of logP vs log V). Patients were divided in 3 groups: Group A included 5 patients studied before and after myocardial infarction who experienced an increase in the modulus of chamber and muscle stiffness after infarction. Group B included 10 patients who were studied at the onset of infarct and 15 days later: this group demonstrated changes in LV compliance with, most often a rightwardshift of P-V curve in anterior infarct and inversely a leftward shift in posterior infarction. The 115 patients of Group B are roughly equally distributed in the areas of normal, increased or decreased compliance. Any correlation was found between the extent of asynergy and changes in modulus of chamber stiffness. However, ejection fraction or VCF were higher in patients with a reduction of compliance than in patients with an increase of compliance.

[Coronary artery spasms]

In a series of 2000 coronary arteriographies, spasm of the coronary artery was found in 52 cases, which were divided into three groups: 41 cases of "iatrogenic" spasm caused by stimulating the ostium of the coronary artery (usually the right) with the tip of the catheter; 8 cases of spasm on top of an organic fixed lesion; 4 cases of coronary spasm on a coronary artery which was reported as "radiologically normal". The study includes a review of the circumstances which favour or impede discovery of coronary spasm, as well as a provocation test using methyl ergometrine. This test seems to be specific in that it only produced coronary spasm in patients with Prinzmetal's syndrome, and excluded the cases of angina with normal coronary arteriography. The patients with spasm on top of a fixed organic lesion underwent a successful aorto-coronary bypass graft together with resection of the pre- and sub-aortic nerve plexus. Patients with a spasm in an artery which was "arteriographically normal" were treated medically by nitrate compounds and vaso-dilators. Three of these patients had an excellent result with medical treatment. Treatment failed in the fourth patient, who then obtained benefit from straight-forward resection of the pre- and sub-aortic nerve plexus with an excellent result which has been maintained for over six months.

[Relationships between pheochromocytoma and obstructive myocardiopathy. Apropos of a case]

The authors report the case of a 45 year old man who presented with a combination of a phaechromocytoma and obstructive cardiomyopathy. They discuss the possible inter-relationships between hypertension, catecholamines, phaeochromocytoma, and outflow stenosis.

[Aneurysms of the membranous septum. Apropos of 4 cases]

Three cases of aneurysm of the membranous septum were diagnosed in vivo. The fourth case was discovered at post-mortem examination in a patient who had a conductive disorder. These four cases give us reason to review the anatomical, clinical, radiological and haemodynamic features of this condition.