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To investigate the intrinsic reactivity of atomic nitrogen, which had previously been accomplished only by examining its decay in the gas phase using special equipment, a nitrogen atom was inserted into a series of molecule-encapsulating C

This study evaluated long-term results following successful endovascular therapy (EVT) for chronic total occlusion (CTO) below the knee (BTK) using the retrograde approach after a failed antegrade approach.Nineteen patients (19 limbs) with critical limb ischemia (CLI) who underwent successful EVT for BTK-CTO using the retrograde approach after a failed antegrade approach during 2010-2014 were studied.Mean duration of the follow-up period was 25.5 ± 17.9 months, and mean age was 76.0 ± 8.6 years. Patients on hemodialysis accounted for 10 cases (52.6%). Patients with Rutherford class 4 constituted 3 cases (15.8%) , while 8 patients each (42.1%) were categorized as Rutherford class 5 and class 6, respectively. All lesions were de novo CTOs. The mean occlusion length was 203.7 ± 114.7 mm. Vascular access for the retrograde approach was obtained via distal puncture in 9 cases (47.4%), whereas the transcollateral approach was employed in 10 cases (52.6%). The amputation-free survival rates at 1, 2, 3, 4, and 5 years after the index procedure were 78.6%, 66.9%, 66.9%, 50.2%, and 50.2%, respectively.Successful EVT for BTK-CTO using various techniques via the retrograde approach provides promising long-term results in patients with CLI.

Additions of adamantylidene (Ad) to M

Background Traditional and non-traditional risk factors for atherosclerotic cardiovascular disease (ASCVD) are different between men and women. Gender-linked impact of epicardial adipose tissue volume (EATV) in patients undergoing coronary artery bypass grafting (CABG) remains unknown. Methods Gender-linked impact of EATV, abdominal fat distribution and other traditional ASCVD risk factors were compared in 172 patients (men: 115; women: 57) who underwent CABG or non-coronary valvular surgery (non-CABG). Results In men, EATV, EATV index (EATV/body surface area) and the markers of adiposity such as body mass index, waist circumference and visceral fat area were higher in the CABG group than in the non-CABG group. Traditional ASCVD risk factors were also prevalent in the CABG group. In women, EATV and EATV index were higher in the CABG group, but other adiposity markers were comparable between CABG and non-CABG groups. Multivariate logistic regression analysis showed that in men, CABG was determined by EATV Index and other ASCVD risk factors including hypertension, dyslipidemia, adiponectin, high sensitive C-reactive protein (hsCRP) and type 2 diabetes mellitus (Corrected R2 = 0.262, p < 0.0001), while in women, type 2 diabetes mellitus is a single strong predictor for CABG, excluding EATV Index (Corrected R2 = 0.266, p = 0.005). Conclusions Our study found that multiple risk factors, including epicardial adipose tissue volume and traditional ASCVD factors are determinants for CABG in men, but type 2 diabetes mellitus was the sole determinant in women. Gender-specific disparities in risk factors of CABG prompt us to evaluate new diagnostic and treatment strategies and to seek underlying mechanisms.

The thermal reaction of the endohedral metallofullerene La2 @D2 (10611)-C72 , which contains two pentalene units at opposite ends of the cage, with 5,6-diphenyl-3-(2-pyridyl)-1,2,4-triazine proceeded selectively to afford only two bisfulleroid isomers. The molecular structure of one isomer was determined using single-crystal X-ray crystallography. The results suggest that the [4+2] cycloaddition was initiated in a highly regioselective manner at the C-C bond connecting two pentagon rings of C72 . Subsequent intramolecular electrocyclization followed by cycloreversion resulted in the formation of an open-cage derivative having three seven-membered ring orifices on the cage and a significantly elongated cage geometry. The reduction potentials of the open-cage derivatives were similar to those of La2 @D2 -C72 whereas the oxidation potentials were shifted more negative than those of La2 @D2 -C72 . These results point out that further oxidation could occur easily in the derivatives.

Fullerenyl radicals can be generated by addition of a free radical to a fullerene surface, by nucleophilic addition followed by one-electron oxidation, or by thermal dissociation of singly bonded fullerene dimers. However, fullerenyl radicals are usually very reactive and generally cannot be isolated. On the contrary, we have found that the reactions of the dimetallic endofullerenes, La2@Ih-C80 and La2@D5h-C80, with 3-chloro-5,6-diphenyltriazine resulted in mono-addition of the triazinyl radical to the fullerene cages to yield isolable fullerenyl radicals. The unusual stability of these fullerenyl radicals arises from the confinement of the unpaired electron to an internal, metal-metal bonding orbital. Accordingly, the fullerene cage protects the radical center from other reactive species. Furthermore, we demonstrate that the fullerenyl radical adduct of La2@Ih-C80 reacts with toluene to afford additional benzylation. Interestingly, the benzylated derivative is diamagnetic in solution, while it forms a paramagnetic dimer when crystallized.

How the electronic properties and chemical reactivity of empty fullerenes can be changed upon endohedral metal-doping? How the dynamic behavior and position of encapsulated metal atoms can be contr...

Thermal reactions of empty fullerenes with disilirane (1) and digermirane (2) afforded the corresponding bis-silylated and bis-germylated derivatives. When a bicyclic fused silirane (3a) was heated in the presence of C70, two silylene adducts were obtained through thermal extrusion of silylenes. These results provide a complementary method to the photochemical addition of reactive silicon and germanium compounds, which have been long employed for derivatization of fullerenes. Electrochemical analyses revealed the redox properties of the silylated and germylated C70, indicating the electronic perturbation caused by silyl and germyl groups introduced on the fullerene cages. Theoretical calculations were also conducted for understanding of the electronic property of the fullerene derivatives.

We prepared nanorods for various endohedral fullerenes as a well-arrayed nanostructure using a liquid–liquid interfacial precipitation method and magnetically aligned them under a magnetic field (10–12 T). The nanorod orientation was observed using a microscope or scanning electron microscopy. Nanorod fullerenes examined in this study include pristine endohedral metallofullerenes [M@C82 (M = La, Ce)] and adamantylidene (Ad) carbene derivatives of mono-metallofullerenes [M@C82Ad (M = La, Ce, Y)], a di-metallofullerene [La2@C80Ad], and a carbon cluster fullerene [Sc3C2@C80Ad], in addition to C60 and its derivative [C60Ad]. Results show that all were aligned and oriented with the axis of nanorods either perpendicularly or in parallel to the fields and demonstrate that this simple technique using magnetic fields is applicable for the fabrication of nanoscale materials.

The endohedral fullerene once erroneously identified as Sc3@C82 was recently shown to be Sc3C2@Ih-C80, the first example of an open-shell cluster metallofullerene. We herein report that benzyl bromide (1) reacts with Sc3C2@ Ih-C80 via a regioselective radical addition that affords only one isomer of the adduct Sc3C2@Ih-C80(CH2C6H5) (2) in high yield. An X-ray crystallographic study of 2 demonstrated that the benzyl moiety is singly bonded to the fullerene cage, which eliminates the paramagnetism of the endohedral in agreement with the ESR results. Interestingly, X-ray results further reveal that the 3-fold disordered Sc3C2 cluster adopts two different configurations inside the cage. These configurations represent the so-called "planar" form and the computationally predicted, but not crystallographically characterized, "trifoliate" form. It is noteworthy that this is the first crystallographic observation of the "trifoliate" form for the Sc3C2 cluster. In contrast, crystallographic investigation of a Sc3C2@Ih-C80/Ni(OEP) cocrystal, in which the endohedral persists in an open-shell structure with paramagnetism, indicates that only the former form occurs in pristine Sc3C2@ Ih-C80. These results demonstrate that the cluster configuration in EMFs is highly sensitive to the electronic structure, which is tunable by exohedral modification. In addition, the electrochemical behavior of Sc3C2@Ih-C80 has been markedly changed by the radical addition, but the absorption spectra of the pristine and the derivative are both featureless. These results suggest that the unpaired electron of Sc3C2@Ih-C80 is buried in the Sc3C2 cluster and does not affect the electronic configuration of the cage.

The reaction mechanism and regioselectivity of the Diels-Alder re- actions of C68 and Sc3N@C68, which vio- late the isolated pentagon rule, were studied with density functional theory calculations. For C68, the (5,5) bond is the most favored thermodynamically, whereas the cycloaddition on the (5,6) bond has the lowest activation energy. Upon encapsulation of the metallic cluster, the exohedral reactivity of Sc3N@C68 is reduced remarkably owing to charge transfer from the cluster to the fullerene cage. The (5,5) bond be- comes the most reactive site thermody- namically and kinetically. The bonds around the pentagon adjacency show the highest chemical reactivity, which demonstrates the importance of penta- gon adjacency. Furthermore, the viabil- ity of Diels-Alder cycloadditions of several dienes and Sc3N@C68 was ex- amined theoretically. o-Quinodime- thane is predicted to react with Sc3N@C68 easily, which implies the pos- sibility of using Diels-Alder cycloaddi- tion to functionalize Sc3N@C68.

This report describes the photochemical behavior of single-walled carbon nanotubes (SWNTs) in the presence of propylamine. The SWNTs are characterized by absorption and Raman spectroscopy. The spectral changes due to photoirradiation indicate that reactions occur predominantly with the metallic SWNTs and small-diameter SWNTs. The detection of amine radicalcation species by ESR spectroscopy reveals photoinduced electron transfer from the amine to the excited SWNTs. After exposure of the photoirradiated SWNTs to air, the characteristic spectra were recovered, except for that of the small-diameter SWNTs. The results suggest that, after photoreduction of the SWNTs, subsequent selective sidewall functionalization of the small-diameter SWNTs occurs.

The [4 + 2] cycloaddition of o-quinodimethanes, generated in situ from the sultine 4,5-benzo-3,6-dihydro-1,2-oxathiin 2-oxide and its derivative, to La metal-encapsulated fullerenes, La2@C80 or La@C82, afforded the novel derivatives of endohedral metallofullerenes (3a,b, 4a,b and 5b). Molecular structures of the resulting compounds were elucidated using spectroscopic methods such as MALDI–TOF mass, optical absorption, and NMR spectroscopy. The [4 + 2] adducts of La2@C80 (3a,b, and 4a,b) and La@C82 (5b), respectively, retain diamagnetic and paramagnetic properties, as confirmed by EPR spectroscopy. Dynamic NMR measurements of 4a at various temperatures demonstrated the boat-to-boat inversions of the addend. In addition, 5b revealed remarkable thermal stability in comparison with the reported [4 + 2] cycloadduct of pentamethylcyclopentadiene and La@C82 (6). These findings demonstrate the utility of sultines to afford thermodynamically stable endohedral metallofullerene derivatives for the use in material science.

Relative concentrations of the nine IPR-based (isolated-pentagon-rule) isomers of Yb@C82 are computed from the Gibbs energy derived from partition functions supplied with parameters from density functional theory calculations. A good agreement with experiment is found at elevated temperatures where the Yb-endohedrals based on the C 2v ;9 and Cs (c);6 C82 cages exhibit comparable concentrations while the third observed species based on the C 2(c);5 cage has about one half of their populations though still a significant presence. The result is somewhat sensitive to the partition-function description.

Reactions of Sc3N@Ih-C80 with aziridine derivatives were conducted to afford the corresponding mono-adducts. A pair of diastereomers of the mono-adduct [5,6]-pyrrolidino-Sc3N@Ih-C80 was isolated and characterized by means of mass spectrometry, vis-NIR absorption spectroscopy, and electrochemical measurements. Structural analysis of the mono-adducts was conducted by NMR and single-crystal X-ray structure determinations.

Endohedral metallofullerenes (EMFs) encapsulating divalent metal ions have rarely been studied because of their low production yields. We report here for the first time the chemical understanding of two typical divalent EMFs, i.e. Yb@D3h-C74 and Yb@C2(13)-C84 with a disilirane reagent (1), which has shown great success in probing the chemical reactivity of EMFs encapsulating a variety of metallic cores. It was surprising to find that Yb@D3h(1)-C74 reacted with 1 neither thermally nor photochemically under normal conditions, showing an unusually low reactivity. However, monoadduct formation was achieved by laser-irradiation of their mixtures during the mass spectroscopic measurement. Accordingly, the thermal and photochemical reactions of Yb@C2(13)-C84 with 1 were conducted under harsher conditions and monoadduct formation was confirmed by both chromatographic and mass spectroscopic studies. The relatively low reactivity of these divalent EMFs compared with that of the corresponding trivalent analogues is ...

Recently, a new member of the lanthanum-containing metallofullerene family has been isolated and its structure determined from X-ray crystallographic analysis, namely La @C ( ,17490), even with two pairs of connected pentagons, hence violating the isolated-pentagon rule (IPR). In order to explain the interesting observation, a computational treatment is suggested for evaluations of the relative populations of nonisomeric metallofullerenes. As a comparative reference structure, the most stable La@C isomer is selected — the IPR-C ( )-cage based endohedral La@C ( ). In the relevant temperature region, the La @C ( ,17490) species should be considerably more populated compared to La@C ( ). The new computational stability treatment is applicable to a wider spectrum of nonisomeric metallofullerenes.

Recently, an extraction of la metallofullerenes from soot using 1,2,4-trichlorobenzene has been reported for La@C80 and La@C82. In both cases, the cages were derivatized by the solvent (forming La@C80-C6H3Cl2 and La@C82-C6H3Cl2) and the following X-ray analysis disclosed rather unexpected cages: C80(C 2v ;3) and C82(C 3v ;7). In order to explain the challenging observations, a two-step computational treatment is presented. The first step deals with the high-temperature gas-phase formation of the underivatized endohedrals while the second step models the reaction with the solvent. The Gibbs free energies were evaluated for representative temperatures and the computational scheme was able to confirm high relative populations for the observed derivatized cages.

In atherosclerosis, carotid artery stenosis (CAS), renal artery stenosis (RAS), lower extremity peripheral arterial disease (PAD), and coronary artery disease (CAD) are common pathologic lesions; their interrelationship is, however, unclear. We studied concomitant multiple atherosclerotic lesions in patients with CAD to understand their prevalence and relations. A cross-sectional analysis was performed on data from consecutive patients who underwent nonemergent coronary angiography. Simultaneous carotid and renal artery Doppler studies and ankle-brachial systolic pressure measurements were reviewed to diagnose concomitant lesions and their severity. The study included 1,734 patients (aged 71 ± 9 years; 70% men), with prevalences of CAS, RAS, lower extremity PAD, and CAD of 6%, 7%, 13%, and 72%, respectively. In patients with CAD (n = 1,253), the prevalences of CAS, RAS, and lower extremity PAD were 7%, 9%, and 16%, respectively; 24% CAD patients had ≥1 additional atherosclerotic lesion. Significant interactions among the prevalences of these lesions were found. In addition, the extent of CAD and the prevalences of CAS, RAS, and lower extremity PAD were significantly correlated. Multivariate analysis supported these relationships. In conclusion, the prevalences of CAS, RAS, lower extremity PAD, and CAD were strongly interrelated in the study population; CAD severity was related to that of other atherosclerotic lesions. Additional systematic screening of other concomitant atherosclerotic lesions is recommended, especially in CAD patients having multivessel disease, left main disease, and/or already diagnosed with other concomitant atherosclerotic lesions.

Although all the pure-carbon fullerene isomers above C60 reported to date comply with the isolated pentagon rule (IPR), non-IPR structures, which are expected to have different properties from those of IPR species, are obtainable either by exohedral modification or by endohedral atom doping. This report describes the isolation and characterization of a new endohedral metallofullerene (EMF), La2@C76, which has a non-IPR fullerene cage. The X-ray crystallographic result for the La2@C76/[Ni(II)(OEP)] (OEP=octaethylporphyrin) cocrystal unambiguously elucidated the C(s)(17,490)-C76 cage structure, which contains two adjacent pentagon pairs. Surprisingly, multiple metal sites were distinguished from the X-ray data, which implies dynamic behavior for the two La(3+) cations inside the cage. This dynamic behavior was also corroborated by variable-temperature (139)La NMR spectroscopy. This phenomenon conflicts with the widely accepted idea that the metal cations in non-IPR EMFs invariably coordinate strongly with the negatively charged fused-pentagon carbons, thereby providing new insights into modern coordination chemistry. Furthermore, our electrochemical and computational studies reveal that La2@C(s)(17,490)-C76 has a larger HOMO-LUMO gap than other dilanthanum-EMFs with IPR cage structures, such as La2@D(3h)(5)-C78 and La2@I(h)(7)-C80, which implies that IPR is no longer a strict rule for EMFs.

Endohedral metallofullerenes (EMFs) are a novel class of metal–carbon hybrid molecules consisting of a fullerene shell and a metal core. Because of the presence of the internal metallic species and charge transfer from metal to cage, EMFs have unique structures and many fascinating properties, which are distinctly different from those of empty fullerenes. The research on EMFs has surprisingly blossomed during recent years, and many practical materials based on EMFs with potential applications in biomedicine, materials science and photovoltaics have been proposed. In this review, we give a systematic and comprehensive summary of the main aspects of EMFs, with emphasis given to experimental results relative to computational work. Finally, perspectives for the future development of EMFs are proposed.

The dream target of artificial photosynthesis is the realization of long-lived radical ion pair states that power catalytic centers and, consequently, the production of solar fuels. Notably, magnetic field effects, especially internal magnetic field effects, are rarely employed in this context. Here, we report on a linear Lu3N@Ih-C80-PDI electron donor-acceptor conjugate, in which the presence of the Lu3N cluster exerts an appreciable electron nuclear hyperfine coupling on the charge transfer dynamics. As such, a fairly efficient radical ion pair intersystem crossing converts the initially formed singlet radical ion pair state, (1)[(Lu3N@Ih-C80)(•+)-PDI(•-)], to the corresponding triplet radical ion pair state, (3)[(Lu3N@Ih-C80)(•+)-PDI(•-)]. Most notably, the radical ion pair state lifetime of the latter is nearly 1000 times longer than that of the former.

This report describes a helicity-selective photoreaction of single-walled carbon nanotubes (SWNTs) with disulfide in the presence of oxygen. The SWNTs were characterized using absorption, photoluminescence (PL), Raman, and X-ray photoelectron spectroscopy, scanning electron microscopy, and current–voltage (I–V) measurements. Results showed remarkable helicity-selective (metallic SWNTs/semiconducting SWNTs and diameter) functionalization of SWNTs. The reaction rate decreases in the order of metallic SWNTs > semiconducting SWNTs and small-diameter SWNTs > large-diameter SWNTs. Control experiments conducted under various experimental conditions and ESR and femtosecond laser flash photolysis measurements revealed that the helicity-selective reaction proceeds via a photoinduced electron transfer reaction. The PL and I–V measurements showed that the photoreaction is effective not only to control SWNT conductivity but also for the band gap modulation of semiconducting SWNTs.

Introducing organosulfur moieties into EMFs is a successful approach for the elucidation of electron transfer behavior of EMFs because the introduced sulfur atoms promote active redox properties in the fullerene molecules. Complexation of La@C82 and unsaturated thiacrown ether, for instance, shows remarkable host–guest interaction and electron transfer to the fullerene. In contrast to these intermolecular electron-accepting properties of EMFs, intramolecular properties were revealed through studies of covalently bonded La2@C80 or La@C82 and π-extended tetrathiafulvalene (exTTF) dyads. These first milestones on the electron transfer behavior have inspired us to ascertain and then expand our knowledge of the unique characteristics of EMFs. These findings suggest potential applications of EMFs based on their unique molecular structure and electronic and magnetic properties as novel carbon nanomaterials.

The cage-like structure of fullerenes enables a new strategy for derivatization, that is, endohedral doping with metallic species. Distinctly different from exohedral metal-fullerene complexes, endohedral metallofullerenes (EMFs) show several new features in metal–carbon interactions which result from the electron transfer from the internal metallic species to the outer carbon cage. Taking advantage of recent achievements in the X-ray crystallographic characterization of EMFs, it was revealed that the single metal cation in mono-EMFs are always apart from the cage center, coordinating with the cage from inside, dominantly via electrostatic interactions, whereas the metal–cage interactions are much weaker in di-EMFs, featuring a moving dimetallic cluster in most cases. Moreover, formation of various metallic cluster species inside the fullerene cage suggest that the strong coordination ability of rare earth metals which always requests a maximal coordinated stereo environments, is a critical factor controlling the formation of stable EMF compounds. Finally, the structural features of the fullerene cage, such as the symmetry, the shape and the size, are also found to exert fundamental influences on the metal location or motion.

We compared the chemical reactivity of D

A 74-year-old man included in the ABSORB EXTEND Clinical Investigation ([NCT01023789][1]) underwent percutaneous coronary intervention with an everolimus-eluting bioresorbable vascular scaffold (BVS) (Absorb BVS1.1, Abbot Vascular, Santa Clara, California) 3.0 × 18 mm in proximal right coronary

The precipitate formed by ultracentrifuging a defatted soybean extract at 200,000×g for 50 min at pH 7.5 was composed of particles of 100-200 nm in diameter and enriched with 34-kDa, 24-kDa and 18-kDa proteins. An SDS-PAGE analysis showed these proteins to migrate to a position identical to that of oil-body-associated proteins (OBAPs; Herman, Planta, 172, 336-345, 1987).(1)) They were recovered in the precipitate of soy protein with 30-40% saturated ammonium sulfate in the presence of 10 mM 2-ME. The lipid composition of the precipitate by a TLC analysis showed that most of the polar lipids in the soybean extract had been condensed in the fraction, suggesting the association between OBAP and the polar lipids. Removal of OBAP and the polar lipids from the soybean extract by conventional centrifugation (10,000×g for 10 min) in the presence of 30 mM Na2SO4 and 30 mM CaCl2 at pH 2.8 was achieved with concomitant improvement of the volatile off-flavor. A soy protein isolate (SPI) prepared from such a soybean extract contained far fewer volatile off-flavor compounds than normal SPI did.

A newly designed electron donor-acceptor conjugate, namely Ce2@Ih-C80-H2P consisting of an endohedral dimetallofullerene Ce2@Ih-C80 and a free-base prophyrin (H2P), has been synthesized and systematically investigated. Basic characterization by means of NMR spectroscopy, steady-state absorption spectroscopy, and electrochemistry points to a folded configuration with sizeable interactions between Ce2@Ih-C80 and H2P. Complementary DFT optimization also results in the same conclusions. Time-resolved absorption spectroscopic investigations corroborate the formation of the (Ce2)˙(-)@Ih-C80-(H2P)˙(+) radical ion pair state in non-polar as well as polar media. Overall, the modus operandi is an ultrafast through-space electron transfer enabled by the folded configuration in the ground and excited state.

Location recognition at the molecular scale provides valuable information about the nature of functional molecular materials. This study presents a novel location sensing approach based on an endohedral metallofullerene, Ce@C82, using its anisotropic magnetic properties, which lead to temperature-dependent paramagnetic shifts in (1)H NMR spectra. Five site-isomers of Ce@C82CH2-3,5-C6H3Me2 were synthesized to demonstrate the spatial sensing ability of Ce@C82. Single-crystal structures, absorption spectra, and density functional theory calculations were used to select the plausible addition positions in the radical coupling reaction, which preferentially happens on the carbon atoms with high electron density of the singly occupied molecular orbital (SOMO) and positive charge. Temperature-dependent NMR measurements demonstrated unique paramagnetic shifts of the (1)H peaks, which were derived from the anisotropic magnetism of the f-electron in the Ce atom of the isomers. It was found that the magnetic anisotropy axes can be easily predicted by theoretical calculations using the Gaussian 09 package. Further analysis revealed that the temperature-dependent trend in the shifts is clearly predictable from the distance and relative position of the proton from the Ce atom. Hence, the Ce-encapsulated metallofullerene Ce@C82 can provide spatial location information about nearby atoms through the temperature-dependent paramagnetic shifts of its NMR signals. It can act as a molecular probe for location sensing by utilizing the anisotropic magnetism of the encapsulated Ce atom. The potentially low toxicity and stability of the endohedral fullerene would make Ce@C82 suitable for applications in biology and material science.

We report that Ce@C

Background Initial and long-term outcomes of the retrograde endovascular approach using a microcatheter for the treatment of chronic total occlusion (CTO) in the iliac or femoropopliteal (FP) arteries have not been fully elucidated. Methods From 2012 to 2014, 20 consecutive patients (21 limbs) underwent endovascular therapy (EVT) for CTO in the iliac or FP arteries using the microcatheter-based retrograde approach. An analysis of the initial and long-term outcomes was conducted. Results All procedures were successful. The mean follow-up duration was 27.4 ± 11.3 months. The mean patient age was 75.8 ± 9.1 years. Eighteen (85.7%) target lesions were located in the superficial femoral artery, 1 (4.8%) in the popliteal artery, and 2 (9.5%) in the iliac artery. All lesions were de novo. The mean occlusion length was 183.3 ± 95.4 mm. A stent was used in 19 (94.5%) lesions and balloon angioplasty was performed for 2 (5.5%) lesions. Retrograde puncture site complication (hematoma in popliteal artery) was reported in 1 (4.8%) patient. Postprocedure primary patency rates at 1, 2, and 3 years were 89.5%, 72.0%, and 41.2%, respectively, and the secondary patency rates at the corresponding time points were 100%, 77.2%, and 48.6%, respectively. Conclusions Initial and long-term outcomes of EVT for CTO in iliac and FP arteries using the microcatheter-based retrograde approach are promising.

Highly regioselective 1,3-dipolar cycloaddition of 3,5-dichloro-2,4,6-trimethoxybenzonitrile oxide (1) to Sc3N@Ih-C80 or C60 affords the corresponding isoxazoline-ring-fused derivatives Sc3N@Ih-C80(C10H9O4NCl2) (2a) and C60(C10H9O4NCl2) (2b). 2a represents the first example of an endohedral metallofullerene derivative with an isoxazoline ring. Crystallographic and NMR spectroscopic studies reveal a [5,6]-bond addition pattern in 2a but a [6,6]-bond addition manner in 2b.

Background Although patients receiving hemodialysis (HD+) have significantly different backgrounds, including a history of progressive atherosclerotic disease, compared with those not receiving hemodialysis (HD−), there are no studies evaluating the risks for loss of primary patency (PP) and need for target lesion revascularization (TLR) in HD+ patients following bare self-expandable nitinol stent (BSNS) implantation to femoropopliteal (FP) artery occlusive lesions, after adjusting for differences using propensity score (PS) analysis in observed characteristics between groups. Methods We studied 531 limbs of 432 Japanese patients (HD+, n =107; HD−, n =325) who received BSNS implantation to FP lesions between 2004 and 2014. Patients were followed-up for an average of 44.3±33.6months. We compared the long-term results between HD+ and HD− patients using the Cox-proportional hazard model with adjustment for inverse probability treatment weight (IPTW) of PS, which was calculated for covariates with HD as a dependent variable. Results PP rate in HD+ vs. HD− patients at 9years after the procedure was 19.1% vs. 47.9%, with a freedom from TLR rate of 47.6% vs. 62.9%, respectively. Adjusted HRs in HD+ patients with 95% confidence intervals (CIs) were as follows: loss of PP: HR 1.64, 95% CI 1.052–2.557, P =0.03; TLR: HR 1.862, 95% CI 1.104–3.139, P =0.02. Conclusions The present study suggests that HD+ patients have an increased risk for loss of PP and need for TLR after BSNS implantation to FP lesions.

To evaluate the long-term outcomes of self-expandable nitinol stent implantation with intraluminal angioplasty for chronic total occlusion (CTO) in the superficial femoral artery (SFA) of patients with TransAtlantic Inter-Society Consensus (TASC) D lesions.From 2004 to 2011, self-expandable nitinol stent implantation in SFA was performed successfully in 72 consecutive limbs of 68 patients with TASC D lesions. These patients were assessed for an average of 38.8 ± 25.6 months. The procedure was performed using a 0.014" or 0.018" guidewire and intraluminal angioplasty.Patients with hemodialysis constituted 20.6% of cases. The mean occlusion length was 244.6 ± 34.1 mm. A bidirectional approach was performed in 69.4% of cases. Primary patency rates were 77.9%, 71.9%, 67.2%, and 51.5% at 1 year, 2 years, 3 years, and 5 years, respectively. Secondary patency rates were 88.6%, 78.7%, 71.1%, and 56.0% at 1 year, 2 years, 3 years, and 5 years, respectively. Cox regression multivariate analysis for hemodialysis pertaining to loss of primary and secondary patency resulted in hazard ratio = 2.555 (95% confidence interval, 1.108-5.891; P=.03) for loss of primary patency and hazard ratio = 3.615 (95% confidence interval, 1.380-9.471; P=.01) for loss of secondary patency.Long-term patency of self-expandable nitinol intraluminal stent implantation with intraluminal angioplasty to treat CTO (TASC D) in SFA is promising. Hemodialysis was the only independent predictor for loss of primary and secondary patency.

Water monomer and dimer encapsulations into D2 (22)-C84 fullerene are evaluated. The encapsulation energy is computed at the M06-2X/6-31++G** level, and it is found that the monomer and dimer storage in C84 yields an energy gain of 10.7 and 17.4 kcal mol(-1) , respectively. Encapsulation equilibrium constants are computed by using partition functions based on the M06-2X/6-31G** and M06-2X/6-31++G** molecular data. Under high-temperature/high-pressure conditions, similar to that for the encapsulation of rare gases in fullerenes, the computed (H2 O)2 @C84 -to-H2 O@C84 ratio is close to 1:2.

Single crystals of three soluble Yb@C(82) isomers, namely, Yb@C(2)(5)-C(82), Yb@C(s)(6)-C(82), and Yb@C(2v)(9)-C(82), cocrystallized with Ni(II)(octaethylporphyrin), allowed accurate crystallographic elucidation of their molecular structures in terms of both cage symmetry and metal location. Multiple metal positions were found in all these isomers, but the major metal sites were found in some specific regions within these cages. Specifically, the Yb(2+) ion prefers to reside close to a hexagonal ring in Yb@C(2)(5)-C(82) and Yb@C(2v)(9)-C(82) but a [5,6,6]-junction carbon atom in Yb@C(s)(6)-C(82). Theoretical calculations at the B3LYP level revealed that these metal positions all correspond to energy minima from the electrostatic potential maps and give rise to the most stable configurations of these Yb@C(82) isomers. Furthermore, it is noteworthy that this is the first report on X-ray crystallographic studies of such metallofullerenes with the popular C(2v)(9)-C(82) encapsulating a divalent metal ion, described as M(2+)@[C(2v)(9)-C(82)](2-).

Functionalization of endohedral metallofullerenes has been shown to differ depending on photochemical or thermal pathways. We report that Lu(3)N@I(h)-C(80) reacts with thermally generated bis(2,6-diethylphenyl)silylene with high selectivity and forms monosilylated derivative 1b. Unexpectedly, 1b undergoes photochemical conversion to afford isomer 1a under ambient light. These adducts were characterized using NMR, visible-near-IR spectroscopy, and matrix-assisted laser desorption ionization time-of-flight mass spectrometry. Single-crystal X-ray structure determination of 1a reveals a rare example of an open 1,2-adduct at the [5,6]-ring junction of the I(h)-C(80) cage. The electrochemical study reveals that the redox potentials of 1a and 1b are shifted cathodically compared to those of pristine Lu(3)N@I(h)-C(80) and that monosilylation is effective to fine-tune the electronic properties of endohedral metallofullerenes as well as empty fullerenes. Density functional theory calculations were also performed, which provide a theoretical basis for the structures and the behavior of the encapsulated Lu(3)N cluster.

It has been an interesting finding that reactions of M@C(2v)(9)-C(82) (M = Y, La, Ce, Gd) with diazirine adamantylidene (AdN(2), 1) gave rise to only two monoadduct isomers, indicating that the cage reactivity of monometallofullerenes is not dependent on the type of the internal metal. However, we found here that Sc@C(2v)(9)-C(82) shows an exceptional chemical reactivity toward the electrophile 1, affording four monoadduct isomers (2a-d). Single-crystal X-ray diffraction crystallographic results of the most abundant isomer (2a) confirm that the addition takes place at a [6,6]-bond junction which is very close to the internal metal ion. Theoretical calculations reveal that 2 out of the 24 nonequivalent cage carbons of Sc@C(2v)(9)-C(82) are highly reactive toward 1, but only one cage carbon of the other M@C(2v)-C(82) (M = Y, La, Ce, Gd) is sufficiently reactive. The exceptional chemical property of Sc@C(2v)(9)-C(82) is associated with the small ionic radius of Sc(3+), which allows stronger metal-cage interactions and makes back-donation of charge from the cage to the metal more pronounced. Our results have provided new insights into the art of altering the chemical properties of fullerene molecules at the atomic level, which would be useful in the future in utilizing EMFs in quantum computing systems.

Narrowly diameter-distributed single-walled carbon nanotubes (SWCNTs) were purely achieved by a facile technique combining microwave irradiation with mixed acid-assisted dispersion. Using this process, besides removal of conventional impurities, both small SWCNTs with highly chemical reactivity and the outer layers of large double-walled carbon nanotubes with more topological defects were preferentially eliminated, retaining only pure SWCNTs of which the diameter distribution was significantly narrowed. The chemical structure of resulting materials was carried by Raman spectroscopy, and electron microscopies. Results revealed that the technique employed is of great efficacy not only for purifying carbon nanotubes, but also especially for narrowing carbon nanotubes. The dual effects of purifying and diameter distribution narrowing make this method promising for achieving high purity single-walled CNTs of specific types. The purification mechanism of the present technique was discussed in detail.

Cardiac hypertrophy is initiated as an adaptive response to sustained overload but progresses pathologically as heart failure ensues. Here we report that genetic loss of APJ, a G-protein-coupled receptor, confers resistance to chronic pressure overload by markedly reducing myocardial hypertrophy and heart failure. In contrast, mice lacking apelin (the endogenous APJ ligand) remain sensitive, suggesting an apelin-independent function of APJ. Freshly isolated APJ-null cardiomyocytes exhibit an attenuated response to stretch, indicating that APJ is a mechanosensor. Activation of APJ by stretch increases cardiomyocyte cell size and induces molecular markers of hypertrophy. Whereas apelin stimulates APJ to activate Gαi and elicits a protective response, stretch signals in an APJ-dependent, G-protein-independent fashion to induce hypertrophy. Stretch-mediated hypertrophy is prevented by knockdown of β-arrestins or by pharmacological doses of apelin acting through Gαi. Taken together, our data indicate that APJ is a bifunctional receptor for both mechanical stretch and the endogenous peptide apelin. By sensing the balance between these stimuli, APJ occupies a pivotal point linking sustained overload to cardiomyocyte hypertrophy.

Metal positions in endohedral metallofullerenes (EMFs) are of special importance because their molecular symmetry and intrinsic properties are strongly influenced by the location and motion of the encapsulated metals. X-ray analyses of the cocrystals of Gd@C(2v)(9)-C(82) with nickel(II) octaethylporphyrin [Ni(II)(OEP)] reveal that the Gd(3+) cation is off-center, being located under a hexagonal ring along the 2-fold axis of the C(2v)(9)-C(82) cage. This result is in sharp contrast to that of a previous study, showing that Gd@C(2v)(9)-C(82) has an anomalous endohedral structure, with the metal being positioned over a [6,6] bond, which is opposite to the hexagonal ring along the C(2) axis (Phys. Rev. B 2004, 69, 113412). In agreement with theoretical calculations and related studies, it is conclusive that the single rare-earth metal in M@C(2v)(9)-C(82) always tends to coordinate with the hexagonal ring along the 2-fold axis, instead of interacting with the [6,6] bond on the other end, regardless of the type of metal atom.