Site Selectivity for the Spin States and Spin Crossover in Undecanuclear Heterometallic Cyanido-Bridged Clusters.

Polynuclear molecular clusters offer an opportunity to design new hierarchical switchable materials with collective properties, based on variation of the chemical composition, size, shapes, and overall building blocks organization. In this study, we rationally designed and constructed an unprecedented series of cyanido-bridged nanoclusters realizing new undecanuclear topology: FeII[FeII(bzbpen)]6[WV(CN)8]2[WIV(CN)8]2·18MeOH (1), NaI[CoII(bzbpen)]6[WV(CN)8]3[WIV(CN)8]·28MeOH (2), NaI[NiII(bzbpen)]6[WV(CN)8]3[WIV(CN)8]·27MeOH (3), and CoII[CoII(R/S-pabh)2]6[WV(CN)8]2[WIV(CN)8]2·26MeOH [4R and 4S; bzbpen = N1,N2-dibenzyl-N1,N2-bis(pyridin-2-ylmethyl)ethane-1,2-diamine; R/S-pabh = (R/S)-N-(1-naphthyl)-1-(pyridin-2-yl)methanimine], of size up to 11 nm3, ca. 2.0 × 2.2 × 2.5 nm (1-3) and ca. 1.4 × 2.5 × 2.5 nm (4). 1, 2, and 4 exhibit site selectivity for the spin states and spin transition related to the structural speciation based on subtle exogenous and endogenous effects imposed on similar but distinguishable 3d metal-ion-coordination moieties. 1 exhibits a mid-temperature-range spin-crossover (SCO) behavior that is more advanced than the previously reported SCO clusters based on octacyanidometallates and an onset of SCO behavior close to room temperature. The latter feature is also present in 2 and 4, which suggests the emergence of CoII-centered SCO not observed in previous bimetallic cyanido-bridged CoII-WV/IV systems. In addition, reversible switching of the SCO behavior in 1 via a single-crystal-to-single-crystal transformation during desolvation was also documented.

The Double Capsule Phenomenon in a Case Series and its Relationship with the Macro-Textured Breast Implant.

BACKGROUND: Silicone breast augmentation remains one of the most common aesthetic surgery procedures, and 2022 marks the 60th anniversary of the first case. Recent studies suggest a link between double capsule (DC) formation and macro-textured devices. METHODS: Between 2010 and 2015, 268 aesthetic patients underwent bilateral mammary prosthesis exchange for indications including PIP exchange, adverse capsular contracture and ultrasonographic evidence of rupture. All surgery, in the form of implant exchange and capsulectomy, was undertaken by the senior author using standard techniques. A retrospective review was undertaken, and data analysed with descriptive statistics and Fisher's exact and Mann-Whitney U tests. RESULTS: Of 268 patients identified, 40 (14.9%) showed some degree of capsular duplication and bilateral involvement was marginally more common (52.5%). Two macroscopic patterns of duplication were observed: complete and subtotal. Complete DCs correlated with a clinical triad of extreme firmness, mobility and minimal-to-no pain. Whilst a wide range of manufacturers was represented, macro-textured devices were associated with the highest DC prevalence (58.3% vs. 5.6%) (Fisher's exact test p < 0.00001). Patients with DC had been implanted for less than half the time, median 52 versus. 120 months (p = 0.0003) of those without. DISCUSSION: An elevated prevalence of duplicate capsules in macro-textured prostheses is reconfirmed in addition to a novel symptom constellation that may assist with clinical diagnosis. Our study reinforces the aetiopathogenic influence of the elastomer in DC formation and reports DC for the first time in non-macrotextured implants. Single-surgeon cohort of 268 consecutive patients with 532 implants Statistically significant association of macro-textured devices with DC Statistically significant reduced duration of implantation of macro-textured devices First report of DC in non-macro-textured devices LEVEL OF EVIDENCE IV: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

Tuning of the phase transition between site selective SCO and intermetallic ET in trimetallic magnetic cyanido-bridged clusters.

A series of crystalline phases composed of trimetallic 3d-5d-5d' {Fe9[Re(CN)8]6-x[W(CN)8]x(MeOH)24}·yMeOH (x = 1 (1), 2 (2), 3 (3), 4 (4) and 5 (5); y = 10-15) clusters were obtained by altering the octacyanidometalate composition. The temperature dependent studies involving SC XRD, SQUID magnetic measurements, IR spectroscopy and 57Fe Mössbauer spectroscopy revealed reversible phase transition with the retention of single crystal character in each congener. The transition was assisted by reversible spin-crossover (SCO) HSFeII↔LSFeII transition at the central Fe1(ii) site for Fe9Re5W1 (1), Fe9Re4W2 (2), Fe9Re3W3 (3) and Fe9Re2W4 (4). In contrast, the tungsten-rich congener Fe9Re1W5 (5) exhibited nontrivial behavior with the SCO transition being stopped halfway through the cooling process, to be completed with single electron transfer (ET) from the external Fe2(ii) center towards one of the neighboring W(v) sites. The critical temperature Tc of SCO has been systematically increased from 193 K (1) to 247 K (4). All experimental data indicate the domination of the Fe(ii)-W(v) valence states in all crystals 1-5, however, with increasing quantity of [W(CN)8]3- (and decreasing quantity of [Re(CN)8]3-), the valence equilibrium Fe(ii)-W(v) ↔ Fe(iii)-W(iv) was systematically shifted to the right, starting from congener 3. The overall electronic configuration at low temperatures and variable amounts and location of spin carriers along the whole series suggest the remarkable competition between magnetic super-exchange Fe(ii)-CN-W(v) interactions and intermolecular interactions. The observed behavior is in line with the information collected previously for the bimetallic congeners Fe9Re6 and Fe9W6, to shed light on the role of the mixed tri-metallic composition in changing the properties observed for the relevant bimetallic cyanido-bridged skeletons.

Modulation of the FeII spin crossover effect in the pentadecanuclear {Fe9[M(CN)8]6} (M = Re, W) clusters by facial coordination of tridentate polyamine ligands.

Spin crossover (SCO) materials, revealing the externally tunable transition between two different spin states, arouse great scientific interest due to their perspective application in information storage, display devices and sensing. Of special importance are the molecular systems offering the possibility of multimodal switching within many spin centers. This is achievable in polynuclear clusters consisting of several SCO-active complexes, however, such molecules are very rare. Herein, we report a unique pair of nanometric pentadecanuclear {Fe9[M(CN)8]6(Me3tacn)8}·14MeOH (Me3tacn = 1,4,7-trimethyl-1,4,7-triazacyclononane, M = Re, 1; M = W, 2) clusters exhibiting a thermally induced spin crossover effect on Fe(ii) complexes, that is on both central and external Fe sites embedded in the cyanido-bridged cluster core. The spin transition occurs gradually in the 120-300 K range, and it is not fully completed even at room temperature. We show that facial coordination of an N,N,N-tridentate Me3tacn ligand dramatically modifies the character of the spin transition phenomenon when confronted with the previously reported {Fe9[M(CN)8]6(MeOH)24}·nMeOH (M = Re, W) clusters by (i) engaging, for the first time, not only central but also external Fe intracluster units in the SCO effect, (ii) cancelling the Fe-W charge transfer pathway, and (iii) decreasing the cooperativity within the supramolecular network.

Tuning of Charge Transfer Assisted Phase Transition and Slow Magnetic Relaxation Functionalities in {Fe(9-x)Co(x)[W(CN)8]6} (x = 0-9) Molecular Solid Solution.

Precisely controlled stoichiometric mixtures of Co(2+) and Fe(2+) metal ions were combined with the [W(V)(CN)8](3-) metalloligand in a methanolic solution to produce a series of trimetallic cyanido-bridged {Fe(9-x)Co(x)[W(CN)8]6(MeOH)24}·12MeOH (x = 0, 1, ..., 8, 9; compounds 0, 1, ..., 8, 9) clusters. All the compounds, 0-9, are isostructural, and consist of pentadecanuclear clusters of a six-capped body-centered cube topology, capped by methanol molecules which are coordinated to 3d metal centers. Thus, they can be considered as a unique type of a cluster-based molecular solid solution in which different Co/Fe metal ratios can be introduced while preserving the coordination skeleton and the overall molecular architecture. Depending on the Co/Fe ratio, 0-9 exhibit an unprecedented tuning of magnetic functionalities which relate to charge transfer assisted phase transition effects and slow magnetic relaxation effects. The iron rich 0-5 phases exhibit thermally induced reversible structural phase transitions in the 180-220 K range with the critical temperatures being linearly dependent on the value of x. The phase transition in 0 is accompanied by (HS)Fe(II) W(V) ↔ (HS)Fe(III) W(IV) charge transfer (CT) and the additional minor contribution of a Fe-based spin crossover (SCO) effect. The Co-containing 1-5 phases reveal two simultaneous electron transfer processes which explore (HS)Fe(II) W(V) ↔ (HS)Fe(III) W(IV) CT and the more complex (HS)Co(II) W(V) ↔ (LS)Co(III) W(IV) charge transfer induced spin transition (CTIST). Detailed structural, spectroscopic, and magnetic studies help explain the specific role of both types of CN(-)-bridged moieties: the Fe-NC-W linkages activate the molecular network toward a phase transition, while the subsequent Co-W CTIST enhances structural changes and enlarges thermal hysteresis of the magnetic susceptibility. On the second side of the 0-9 series, the vanishing phase transition in the cobalt rich 6-9 phases results in the high-spin ground state, and in the occurrence of a slow magnetic relaxation process at low temperatures. The energy barrier of the magnetic relaxation gradually increases with the increasing value of x, reaching up to ΔE/kB = 22.3(3) K for compound 9.

Fibrin tissue adhesive for face- and necklift.

INTRODUCTION: Although available for decades, fibrin-based tissue adhesives (FTAs) have enjoyed only variable popularity in aesthetic surgery since their introduction in the 1980s. Whilst benefits in facelift surgery have been reported for a range of measures, including expanding haematoma, oedema and ecchymosis, irrefutable evidence has not yet been forthcoming. We instigated a prospective study to test the hypothesis that an underappreciated property of FTA, namely its ability to distribute tension, would reduce complications and revision due to early relapse. PATIENTS AND METHODS: The study group comprised 100 consecutive facelifts with FTA. The comparative group comprised the immediate preceding 100 patients who underwent similar interventions, but with drains instead of FTA. All surgery was undertaken by the senior author using standard techniques and statistical analysis employing Fisher's exact test. RESULTS: The groups were comparable in age, gender distribution, co-morbidity and declared cigarette smoking. Complications were recorded in 24 patients with significantly more in the comparative group (p = 0.048), particularly hypertrophic scarring (p = 0.029). Although there appeared a greater prevalence of revision and cutaneous necrosis in the comparative group, these did not reach statistical significance. DISCUSSION: To the many published benefits, we can add that FTA can reduce complications, particularly hypertrophic scarring, and it now forms an important part of our facelift practice.

PIP implant biodurability: a post-publicity update.

INTRODUCTION: in the year since Poly Implant Prothèse (PIP) found itself the epicentre of intense, global media attention initial studies have started to evaluate the abnormally high premature device failure rate suspected for their mammary prostheses. A cohort free from most of the usual confounding variables affords opportunities to improve upon previous estimates of rupture prevalence, assess the media effect and evaluate contemporary ultrasound scan (USS) accuracy. PATIENTS & METHODS: 460 patients who underwent cosmetic breast augmentation (BA) with PIP silicone prostheses (January 2000-August 2005) have now been followed since their withdrawal in 2010. Initial recall study generated a crude rupture rate of 15.9-33.8% over 6-11 years. Global publicity that followed the lymphoma-related death of a French patient in December 2011 led to 127 patients (27.4%) of our original cohort making de novo or further contact as a direct result. To date, 283 (61.5%) have been reviewed of whom 167 (59%) have undergone breast USS. In toto, 163 (35.4%) have had their implants replaced or removed. RESULTS: Kaplan-Meier analysis places 10-year PIP mammary implant survival between 60 (95% confidence interval (CI): 54-67) and 81% (95% CI: 78-85). Post-publicity evaluees were found to have occult device failure in 31.6%. Of 85 patients who had definitive confirmation of USS findings by surgical exploration, 79 (92.9%) were completely accurate. USS in our series had a sensitivity of 97.3% and specificity of 93.1%. DISCUSSION: this study not only reaffirms PIP's rupture prevalence to be higher than comparative breast prostheses, but also records the media's beneficial effect in improving recall. Importantly, there is a relatively high proportion of patients with ruptured devices of which they are otherwise unaware. Ultrasonography, at least in PIP-augmented women, seems to be a more accurate tool than previously measured, especially in the presence of rupture. Finally, 35.2% resisted all attempts at review despite repeated efforts and widespread media coverage.

Botulinum neurotoxin A: a review.

Despite its ubiquity in cosmetic circles and broad general awareness, a literature search of botulinum neurotoxin in JPRAS and BJPS yielded a mere 4 articles germane to cosmesis. A pair each detailing its application in masseteric hypertrophy(1,2) and the use of cryoanalgesia.(3,4) Given that botulinum neurotoxin A is the most commonly used cosmetic treatment, with American figures being most accurate,(5) a review of the background, development and scientific evidence would be perhaps useful, if not overdue, as Plastic Surgeons increasingly incorporate non-surgical interventions into their practices as part of a comprehensive facial rejuvenation strategy.

The PIP mammary prosthesis: a product recall study.

INTRODUCTION: Concerns about the durability of silicone breast implants manufactured by Poly Implant Prothèse (PIP) have been expressed for several years prior to their formal withdrawal from the market in March 2010. Although precise details of what elements were at fault remain unclear, concerns have been raised about both the elastomer and the filler gel. Media speculation has focussed on device safety, longevity and, recently, a possible association with lymphoma, specifically anaplastic large cell lymphoma (ALCL). There is however, no actual data concerning these implants with which to guide and inform when concerned patients seek advice. PATIENTS AND METHODS: PIP mammary prostheses were used by the senior author for both primary and revision breast augmentation (BA) during the period January 2000-August 2005. A database of patients was constructed and attempts made to contact each patient offering a free consultation and referral for ultrasound scan (USS). Chief outcome measures included secondary surgery, the implant rupture rate and time to rupture. RESULTS: 453 consecutive patients with PIP devices were identified. Of this number 30 had already undergone implant exchange for a variety of reasons. 180 (39.7%) could not be contacted and 19 had undergone explantation elsewhere, including the NHS. Of those who could be contacted, 47 declined consultation as they had no concerns. 97 had neither clinical signs nor radiographic evidence of implant rupture and elected to remain under regular review. At the time of writing, 38 have undergone implant exchange after ultrasonographic indication of rupture and the overall patient rupture rate for the PIP implant is 15.9-33.8%. This cohort correlates reduced implant longevity with each successive year from 2000 and no cases of ALCL have been diagnosed. DISCUSSION: Long-term studies such as this are difficult to undertake for a number of reasons as they place a significant additional burden of resources on a practice. They are, however, essential from an industry perspective both for the provision of information and supporting audit and professional standing. Being only a single-handed practice, this initial study is the tip of an iceberg that may affect 40,000 women in the UK with PIP implants, but it does provide some hard data with which to guide our patients. It is also believed to be the first independent product recall study in aesthetic breast surgery.