Publisher Correction: Fe-functionalized paramagnetic sporopollenin from pollen grains: one-pot synthesis using ionic liquids.

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

Fe-functionalized paramagnetic sporopollenin from pollen grains: one-pot synthesis using ionic liquids.

The preparation of Fe-decorated sporopollenins was achieved using pollen grains and an ionic liquid as solvent and functionalizing agent. The integrity of the organic capsules was ascertained through scanning electron microscopy studies. The presence of Fe in the capsule was investigated using FT-IR, X-ray photoemission spectroscopy and energy-dispersive X-ray spectroscopy. Electron paramagnetic resonance and magnetization measurements allowed us to demonstrate the paramagnetic behavior of our Fe-functionalized sporopollenin. A few potential applications of pollen-based systems functionalized with magnetic metal ions via ionic liquids are discussed.

Implant site preparation using ultrasonic technique vs. Conventional drilling: three-year follow-up of a split-mouth study.

The aim of this split-mouth study was to evaluate the effectiveness of ultrasonic technique for implant site preparation when compared with the conventional drilling technique. A total of 98 bilateral single implants were placed in 49 patients. For each patient, traditional drilling technique was used at one side (control) and ultrasonic technique was used at the other side (test). Prior to insertion all implants were carefully embedded in liquid plasma rich in growth factors. Clinical and radiographic results were assessed after three years of function. The same implant success rate (95.9%) was recorded for both groups in a three year follow up, with only two implants lost per group. At the last follow-up the mean peri-implant bone loss was 0.42 ± 0.14 mm and 0.33 ± 0.13 mm in the control and test group, respectively. The difference was significant (P<0.001). In conclusion, ultrasonic technique for implant site preparation showed similar clinical performance but better preservation of the peri-implant bone. Together with the known characteristics of safety and reduced bleeding at the surgical site the ultrasonic technique represents a valuable alternative to traditional drilling.

Preventive oral surgery before bisphosphonate administration to reduce osteonecrosis of the jaws.

OBJECTIVES: The intravenous injection of bisphosphonates, currently used for osteoporosis, myeloma, or bone metastases, can cause ONJ especially in consequence of trauma. To avoid trauma during bisphosphonate treatment, preventive oral surgery is recommended. The research aimed to evidence whether inflammatory and osteoclastogenic factors are not induced in oral mucosa after bisphosphonate treatment in patients receiving oral preventive surgery procedure and whether proliferation factors are not inhibited. PATIENTS AND METHODS: Specimens of oral mucosa were removed from healthy subjects and from patients undergoing preventive oral surgery before bisphosphonate treatment. The expression of cytokines and factors involved in osteoclast activity, cell proliferation, and angiogenesis were examined. RESULTS: Cytokines and RANK-L levels decreased significantly in mucosa from patients undergoing preventive oral surgery procedure before bisphosphonate treatment in comparison with their levels at the beginning of procedure and also in comparison with the level in patients treated only with bisphosphonates and not developing ONJ; conversely, osteoprotegerin and hydroxymethylglutaryl coenzyme A reductase significantly increased or not changed. CONCLUSIONS: The results suggest that preventive oral surgery could be able to prevent ONJ due to bisphosphonate treatment: The mucosa is not stimulated by bisphosphonates to cause ONJ, as bisphosphonates are probably not released from the bone.

Labeling interacting configurations through an analysis of excitation dynamics in a resonant photoemission experiment: the case of rutile TiO2.

A detailed study of resonant photoemission at Ti L(2,3) edges of insulating rutile TiO(2-x) thin film is presented. Pure TiO(2) resonating structures, defect-related resonances, resonant Raman-Auger and normal LVV Auger emissions are tracked, including an unpredicted two-hole correlated satellite below the non-bonding part of the valence band. The analysis of excitation dynamics unambiguously addresses the origin of these features and, in particular, the extent of charge transfer effects on the Ti-O bonding in the valence band of rutile, disclosing further applications to the more general case of, formally, d(0) oxides.

Tooth extraction in osteoporotic patients taking oral bisphosphonates.

UNLABELLED: This prospective study compares two different surgical protocols with different degrees of invasiveness for tooth extraction in patients treated with oral bisphosphonates (BPs). No intraoperative complications were observed in either of the two groups, and there was no evidence of postoperative bisphosphonate-associated osteonecrosis of the jaw in any of the extractions in the study group at follow-up (1,480 extractions). According to our data, dental extraction seems to be safe in osteoporotic patients treated with oral bisphosphonates. INTRODUCTION: Oral bisphosphonates are drugs commonly prescribed for the treatment of osteoporosis and other resorptive bone diseases. Since 2003, there have been numerous publications relating bisphosphonate-related osteonecrosis of the jaw (BRONJ) in patients using oral bisphosphonates, such as alendronate and risedronate. Most of the BRONJ cases reported in literature show a strong correlation with dental pathologies, dental extractions, and/or oral surgical procedures. METHODS: This study was conducted on 700 consecutive patients treated with oral bisphosphonates who underwent dental extractions. A total of 1,480 extractions were involved: 864 in the mandible and 616 in the maxilla. The patients were assigned randomly to one of two groups: 334 were treated with delicate surgery and closure by primary intention (Protocol A), and the other 366 were treated with nontraumatic avulsion and closure by secondary intention (Protocol B). All patients were administered with antibiotics coverage. RESULTS: Seven hundred patients with required removal of compromised teeth were included in the study. No intraoperative complications were observed in either of the two groups, and there was no evidence of postoperative bisphosphonate-associated osteonecrosis of the jaw in any of the extractions in the study group at follow-up (1,480 extractions). CONCLUSIONS: The findings of this prospective study indicate that both suggested protocols for tooth extraction in patients treated with oral BPs can provide a predictable treatment outcome (100 % success). Therefore, because atraumatic surgery is more comfortable for patients, we suggest the adoption of Protocol B, which limits trauma to both the soft and hard tissues.

Hydroxyapatite paste Ostim, without elevation of full-thickness flaps, improves alveolar healing stimulating BMP- and VEGF-mediated signal pathways: an experimental study in humans.

OBJECTIVE: Tooth extraction is considered as the starting point of jaw atrophy via osteoclast activity stimulation. The maintenance of dental alveolar bone depends on surgery procedure and use of materials to maintain prior space favoring bone regeneration. Among substitutes used in dentistry to fill bone defects, Ostim-Pastes (Ostim) is a nanocrystalline paste tested for treatment of severe clinical conditions. This research first investigated the effect of Ostim on alveolar healing, comparing in the same healthy subjects, an Ostim-filled socket with a not-filled one. Moreover, it also proposed a new surgical protocol for the post-extractive socket treatment using the graft materials without elevation of full-thickness flaps. MATERIAL AND METHODS: Fourteen patients were enrolled to bilateral maxillary or mandibular extraction that was performed without elevation of full-thickness flaps. In each patient, one socket was filled using Ostim, and the other one was allowed to undergo natural healing. No suture was carried out. Clinical and biologic parameters were screened at 1, 7, and 14 days. RESULTS: Obtained results evidenced that nanocrystalline hydroxyapatite supports bone regeneration, increasing the synthesis of pro-osteogenic factors as bone morphogenetics protein (BMP)-4, BMP-7, alkaline phosphatase, and osteocalcin. Moreover, filling post-extractive socket with nanocrystalline hydroxyapatite paste leads to a complete epithelialization already at 7 days after extraction, despite the fact that the teeth were extracted without elevation of full-thickness flaps . The improved epithelialization is mediated by increased vascular endothelial growth factor (VEGF) expression. No significant change was observed in inflammatory parameters, with exception of an early and transient IL-1ß induction, that could trigger and improve alveolar healing. CONCLUSIONS: Clinical and biomolecular observations of this explorative study evidenced that nanocrystalline hydroxyapatite improves alveolar socket healing, increasing angiogenesis, epithelialization, and osteogenesis, also in absence of elevation of full-thickness flaps.

Exposing human epithelial cells to zoledronic acid can mediate osteonecrosis of jaw: an in vitro model.

BACKGROUND: Osteonecrosis of the jaw (ONJ) is a chronic complication of bisphosphonate therapy, mainly when intravenous, in cancer patients with bone metastases and myeloma. Its pathophysiology is not yet fully elucidated; in particular, the molecular/cellular events triggering ONJ remain unclear. This complication could result from the effect of bisphosphonates released from bone into the soft-tissues, or from osteolysis induced by soft-tissues directly exposed to bisphosphonates. This research investigated the possibility that ONJ may be evocated by changes induced in osteoblast activity by factors released by soft-tissue cells exposed to zoledronic acid. METHODS: An 'in vitro' model was used, in which human osteoblast-like MG-63 cells were grown in medium conditioned by human keratinocytes NCTC 2544, exposed or not to zoledronic acid (5 or 50 µM); 5 µM zoledronic acid was also directly administered to MG-63 cells. RESULTS: In NCTC 2544 cells, zoledronic acid decreased proliferation via decreased hydroxy-3-methyl-glutaryl-CoA reductase, suggesting that a decrease in healing capability can occur in case of injury. An increased pro-inflammatory potential was also observed. Osteoblasts grown in medium conditioned in the presence of zoledronic acid showed decreased proliferation and osteogenic properties, and increased ability to induce osteoclast differentiation and inflammatory process. Zoledronic acid directly administered to MG-63 modulated only some parameters and in a lesser extent. CONCLUSIONS: The research evidenced, for the first time, the direct involvement of epithelial cells in zoledronic acid-triggered molecular mechanisms leading to osteonecrosis of the jaw, by modulating both osteoblast and osteoclast properties.

Impact of dental care in the prevention of bisphosphonate-associated osteonecrosis of the jaw: a single-center clinical experience.

BACKGROUND: Osteonecrosis of the jaw (ONJ) is associated with bisphosphonate (BP) therapy and invasive dental care. An Interdisciplinary Care Group (ICG) was created to evaluate dental risk factors and the efficacy of a preventive restorative dental care in the reduction of ONJ risk. PATIENTS AND METHODS: This prospective single-center study included patients with bone metastases from solid tumors. Patients who received at least one BP infusion between October 2005 and 31 August 2009 underwent one or more ICG evaluation and regular dental examinations. We also retrospectively evaluated patients with bone metastases from solid tumors who did not undergo dental preventive measures. RESULTS: Of 269 patients, 211 had received at least one infusion of BP therapy: 62% were BP naive and 38% had previous BP exposure. Of these 211 patients followed for 47 months, 6 patients developed ONJ (2.8%). Of 200 patients included in the retrospective analysis, 11 patients developed ONJ (5.5%). CONCLUSIONS: In comparison with published ONJ rates and those extrapolated from the retrospective analysis, the observed ONJ rate in the prospective group was lower, suggesting that implementation of a preventive dental program may reduce the risk of ONJ in metastatic patients treated with i.v. BP therapy.

Pressure effects in the isoelectronic REFe0.85Ir0.15AsO system.

The effect of chemical and hydrostatic pressure has been studied systematically in a selected system belonging to the 1111 family of iron pnictide high-temperature superconductors. The results show a surprising similarity between the trend of critical temperature vs hydrostatic pressure for isoelectronic samples with different rare earths (RE) on the RE site and samples of the SmFeAsO(1-x)F(x) series with different doping levels. These results open new questions about the underlying mechanism for superconductivity in iron pnictides.

Vascular endothelial growth factor genetic polymorphisms and haplotypes in female patients with bisphosphonate-related osteonecrosis of the jaws.

OBJECTIVE: To investigate the polymorphisms of the vascular endothelial growth factor (VEGF) gene in relation to female patients who developed bisphosphonate-related osteonecrosis of the jaws (BRONJ). METHODS: Test subjects were 30 Italian female patients with BRONJ (Group A). Control subjects were 30 female patients with a history of intravenous bisphosphonate use without any evidence of osteonecrosis (Group B) and 125 unrelated healthy volunteers (Group C). Three single-nucleotide polymorphisms were investigated: -634 G>C, occurring in 5' untranslated region (UTR); +936 C>T, occurring in 3' UTR; and -2578 C>A of the promoter region. RESULTS: The frequency of the VEGF CAC (+936/-2578/-634) haplotype was increased in patients with BRONJ, compared with female disease-negative controls [odds ratio (OR) = 2.76, 95% CI = 1.09-4.94, P = 0.039; corrected P value: P(c) = 0.117], and was also increased compared with female healthy controls (OR = 2.11, 95% CI = 1.14-3.89, P = 0.024; corrected P value: P(c) = 0.072). The CC homozygotes of -634G>C of VEGF gene and AA homozygotes of -2578C>A have also been significantly correlated in female patients who developed BRONJ compared with healthy controls (OR = 2.04, 95% CI = 1.12-3.70, P = 0.008; corrected P value: P(c) = 0.024). CONCLUSIONS: These results suggest a possible haplotype effect of VEGF polymorphisms expression in BRONJ Italian female patients. Studies with different and larger populations possibly using TagSNP to represent all haplotypes within the VEGF gene are needed to further delineate the genetic contribution of this gene to BRONJ.

Phase diagram of NdFeAsO(1-x)F(x): essential role of chemical composition.

In this Article, we provided the complete phase diagram of NdFeAsO(1-x)F(x) solid solution as a function of electron doping thanks to the careful determination of F- and O-content and phase content. We gave direct evidence of the source of F-depletion in the superconducting main phase, that is, the formation of oxyfluoride spurious phase. The approach reported in this work clearly showed that to give reliable results on these complex new superconducting materials, a rigorous control of the chemical composition of the considered phases has to be carried out.

Control of F-doping in pnictide high-temperature superconductors.

In this paper we show the relevant role of F-content control in pnictide oxide superconductors by providing a direct evidence of F-loss in samples prepared by means of routine synthetic methods.

Strong electronic correlations in LixZnPc organic metals.

Nuclear magnetic resonance, electron paramagnetic resonance and magnetization measurements show that bulk LixZnPc are strongly correlated one-dimensional metals. The temperature dependence of the nuclear spin-lattice relaxation rate 1/T_{1} and of the static uniform susceptibility chi_{S} on approaching room temperature are characteristic of a Fermi liquid. Moreover, while for x approximately 2 the electrons are delocalized down to low temperature, for x-->4 a tendency towards localization is noticed upon cooling, yielding an increase both in 1/T_{1} and chi_{s}. The x dependence of the effective density of states at the Fermi level D(E_{F}) displays a sharp enhancement for x approximately 2, at the half filling of the ZnPc lowest unoccupied molecular orbitals. This suggests that LixZnPc is on the edge of a metal-insulator transition where enhanced superconducting fluctuations could develop.

Synthesis and characterization of pure and doped (Na, Ca, Sr) nanograined LaMnO3 magnetoresistive ceramics.

Pure and Na, Ca, and Sr doped lanthanum manganites (LaMnO3, La0.85Na0.15MnO3, La0.7Ca0.3 MnO3, La0.7Sr0.3MnO3) were prepared in form of bulk nano-structured materials through a two-step process. Nanometric powders were synthesized by the Pechini method and subsequently densified by Spark Plasma Sintering at 1273 K for 5 minutes under a pressure of 140 MPa. The method allowed the preparation of single phase manganites with a theoretical density above 98% together with a very limited growth of the grain size. Grain sizes below 70 nm were obtained for all materials except La0.85Na0.15MnO3 which showed a much larger grain size. Curie temperatures (Tc) and magnetoresistivity properties of the samples were measured by a Superconducting Quantum Interference Device (SQUID). The decrease in the resistivity below Tc occurred in a much wider range of temperature compared to ceramics having micron-size grains.

Effect of superpulsed laser irradiation on bone formation in a human osteoblast-like cell line.

AIM: The effect superpulsed of low-level laser therapy (SLLLT) on bone regeneration has been the focus of recent research. This preliminary study investigated the effect of superpulsed laser irradiation on proliferation and bone formation in human osteoblast-like cells MG-63. METHODS: Human osteoblast-like cells MG-63 were exposed every 24 h to superpulsed low-level laser produced by the device Lumix 2 HFPL Dental (Fisioline s.n.c., Verduno, Cuneo, Italy); the experimental protocol comprised 4 days of treatment. At each experimental time, cell proliferation and some markers of osteoblast activity were evaluated. RESULTS: Numbers of laser-treated cells increased starting from day 2 of treatment. The ability of SLLLT irradiation to stimulate bone production was evaluated by determining the expression of osteocalcin and alkaline phosphatase, proteins involved in calcium nodule formation. These proteins increased markedly after 3 days of laser treatment. CONCLUSIONS: These preliminary results show that repeated SLLLT irradiation stimulates cell proliferation in human osteoblast-like cells and, importantly, increases the expression of proteins essential for bone formation.

Structural and spectroscopic properties of pure and doped Ba6Ti2Nb8O30 tungsten bronze.

Pure and doped Ba(6)Ti(2)Nb(8)O(30) (BTN), obtained by substituting M = Cr, Mn, or Fe on the Ti site (Ba(6)Ti(2-x) M(x)Nb(8)O(30), x = 0.06 and 0.18) and Y and Fe on the Ba and Ti sites, respectively (Ba(6-x)Y(x)Ti(2-x)Fe(x)Nb(8)O(30), x= 0.18), are synthesized. The influence of cation doping on the local structure, the cation oxidation state, and the possible defect formation able to maintain the charge neutrality are investigated by spectroscopic (electron paramagnetic resonance (EPR) and micro-Raman), structural (X-ray powder diffraction) and transport (impedance spectroscopy, thermoelectric power) measurements, in the temperature range of 300-1200 K in air and N(2) flow. Starting from the valence state of the doping ions (Fe(3+), Cr(3+), and Mn(2+)), determined by EPR, and from thermoelectric power measurements, evidencing a negative charge transport, different charge-compensating defect equilibria, based on the creation of positive electron holes or oxygen vacancies and electrons, are discussed to interpret the conductivity results.

Ferromagnetism on a paramagnetic host background: the case of rutile TM:TiO(2) single crystals (TM = Cr, Mn, Fe, Co, Ni, Cu).

Single crystals of TiO(2) rutile doped with Cr, Mn, Fe, Co, Ni, and Cu were grown with the flux method in a Na(2)B(4)O(7) melt. The samples, checked in their structural and phase homogeneity by x-ray diffraction and micro-Raman spectroscopy, were single-phase needle-shaped crystals several millimetres long. Paramagnetic and ferromagnetic behaviours at room temperature were observed and they are discussed also in connection with the magnetic properties of undoped TiO(2) crystals.