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The substituents in 2,6‐bis(2‐R‐2H‐tetrazol‐5‐yl)pyridyl neutral ligands R2btp (R=Me, tBu) revealed a prominent effect when reacting with iron(II) salts, in combination with the nature of the anion. According to metal:ligand molar ratio, reaction of R2btp with FeCl2 led to isolate [FeII(R2btp‐κ3N,N',N")2](FeIIICl4)2, R=Me (1 a) and tBu (2 a), where the octahedral iron(II) centres bring two tridentate ligands in mer coordination mode, but also [FeII(tBu2btp‐κ3N,N',N")(tBu2btp‐κN)2(H2O‐κO)](FeIIICl4)2 (2 b), where one ligand is tridentate, while the other two coordinate the iron(II) through one tetrazolyl nitrogen atom, and the octahedral sphere is completed by one water molecule. In all cases, half of the iron ions are oxidised to iron(III) forming the paramagnetic tetrachloroferrato counterions. Reaction of tBu2btp with Fe(ClO4)2 ⋅ 6H2O led to the octahedral [FeII(tBu2btp‐κ3N,N',N")2](ClO4)2 ⋅ 4DCM (4 a ⋅ 4DCM), which shows solvent‐dependent spin crossover behaviour: while 4 a ⋅ 4DCM is blocked in the high spin state, its unsolvated form, 4 a, undergoes spin transition to low spin in two subsequent steps at 206 K, with opening of a 23‐K hysteresis (T1/2↓=194 K, T1/2↑=217 K), and at 136 K (T1/2↓=135 K, T1/2↑=137 K). The magnetic profile changes to an incomplete spin transition when the sample absorbs water molecules yielding 4 a ⋅ 1.5H2O. [ABSTRACT FROM AUTHOR]

Purpose: Anterior cruciate ligament repair techniques are of growing interest because they allow for minimally invasive surgery that avoids harvesting of the transplant, without risking growth deficiencies in young patients. The aim of this study is to summarize the published evidence about arthroscopic repair of anterior cruciate ligament proximal tears in skeletally immature patients. Methods: In total, four studies were included and processed for data extraction after screening for eligibility for this systematic review: one retrospective cohort study and three retrospective case series. Altogether, the four studies included in this review included 61 skeletally immature patients with a mean age of 12.1 years diagnosed with proximal anterior cruciate ligament tear who underwent arthroscopic repair with preservation of the native ligament. The mean follow-up period was 2.8 years. Results: The most relevant and objective outcome that we considered was re-rupture rate. One study reports a cumulative incidence of graft failure in the first 3 years after surgery of 48.8% while the others report a 0%, 0% and 21.5% re-rupture rate. No growth disturbances were reported in the included studies. Conclusion: Despite growing interest surrounding anterior cruciate ligament repair techniques, the presence of limited quality studies in the literature means repair cannot be strongly supported at present. Some encouraging data regarding the absence of growth disturbance and functional outcomes does exist, but studies with larger samples are required. Level of evidence: level IV. [ABSTRACT FROM AUTHOR]

Iron(II) can show a very rich coordination chemistry with concomitant modulation of its properties as promising functional materials. Metalation of the neutral tridentate nitrogen-donor mer-coordinating ligand 2,6-bis(2-(methyl)-2H-tetrazol-5-yl)pyridine (Me2btp) with Fe(ClO4)2·6H2O through accurate solvent polarity control enables the selective crystallization of [FeHS/LS(Me2btp)2](ClO4)2·MeCN·2.75H2O (2HS/LS·MeCN·2.75H2O) as red rods, where half of the iron(II) centres resides in the low spin (LS, S = 0) state and the other half is in the high spin (HS, S = 2) state. The red rods spontaneously convert into yellow crystals once removed from the mother liquor and exposed to air due to solvent rearrangement within the crystal packing; these new crystals can be assigned to [FeHS(Me2btp)2](ClO4)2·solvent (2HS·solvent) where all the iron(II) centres are now blocked in the HS state, as confirmed by magnetic measurements. The polarity of the crystallization solvent, together with the maintenance of the crystals within the mother liquor, are pivotal for the reactivity and interconversion of different species. Indeed, upon long standing in solution, 2HS/LS·MeCN·2.75H2O converts to another form of red crystals belonging to [FeLS(Me2btp)2][FeHS(Me2btp)(MeCN)2(H2O)](ClO4)4·MeCN (2LS·3HS·MeCN), as confirmed by single crystal X-ray diffraction data. In this co-crystal, the iron(II) in 2 resides in the LS state at all temperatures while the iron(II) in 3 is blocked in the HS state. Well-formed yellow crystals could be also isolated among the red crystals of 2HS/LS·MeCN·2.75H2O, and they could be identified as the unprecedented octacoordinated species [Fe(Me2btp)2(MeCN)(H2O)](ClO4)2·H2O (1·H2O) by single-crystal X-ray diffraction. These yellow crystals are stable in the air, but slowly convert into 2LS·3HS·MeCN if kept in the mother liquor for about one week. 1·H2O can be considered the trapped intermediate in the solid state during the conversion of [FeHS(Me2btp)2]2+ into [FeHS(Me2btp)(MeCN)2(H2O)]2+ in solution, where the two tridentate ligands in the starting species can unfold to accommodate coordinated MeCN and H2O molecules, as confirmed by theoretical calculations, and eventually one of the two Me2btp is completely replaced by the solvent. [ABSTRACT FROM AUTHOR]

With the clear need for better cancer treatment, naturally occurring molecules represent a powerful inspiration. Recently, curcumin has attracted attention for its pleiotropic anticancer activity in vitro, especially against colorectal and prostate cancer cells. Unfortunately, these encouraging results were disappointing in vivo due to curcumin's low stability and poor bioavailability. To overcome these issues, herein, the synthesis of eight new pyrimidine–curcumin derivatives is reported. The compounds were fully characterized (1H/13C NMR (Nuclear Magnetic Resonance), LC-MS (Liquid Chromatography-Mass Spectrometri), UV-Vis spectroscopy), particularly their acid/base behavior; overall protonation constants were estimated, and species distribution, as a function of pH, was predicted, suggesting that all the compounds are in their neutral form at pH 7.4. All the compounds were extremely stable in simulated physiological media (phosphate-buffered saline and simulated plasma). The compounds were tested in vitro (48 h incubation treatment) to assess their effect on cell viability in prostate cancer (LNCaP and PC3) and colorectal cancer (HT29 and HCT116) cell lines. Two compounds showed the same anti-proliferative activity as curcumin against HCT116 cells and improved cytotoxicity against PC3 cells. [ABSTRACT FROM AUTHOR]

This review thoroughly covers aspects of synthetic chemistry, reactivity, and the properties of dinuclear and oligonuclear actinoid complexes based on Schiff base ligands within the last 20 years in an extensive way and with clear presentation. 10.3390/molecules181012264 6 Liu X., Hamon J.-R. Recent Developments in Penta-, Hexa- and Heptadentate Schiff Base Ligands and Their Metal Complexes. As stated by two of the seven papers [[1]] published in the Special Issue entitled "Oligonuclear Metal Complexes with Schiff Base Ligands" that I guest edited, the chemistry of Schiff bases began in 1864 due to the discovery made by Hugo Schiff [[3]], but even more than one and a half centuries after their first synthesis, Schiff bases continue to surprise inorganic chemists. C=N is usually incorporated into more articulated architectures in addition to other donor atoms, the so-called polydentate ligands [[6]], since metal complexes with macrocyclic and acyclic polydentate Schiff bases [[7]] show enhanced thermodynamic stability due to the chelating effect [[9]]. [Extracted from the article]

Knee osteoarthritis (OA) is a chronic degenerative inflammatory-based condition caused by a cascade of different intra-articular molecules including several cytokines. Among the cytokines, prokineticins (PKs) have recently been identified as important mediators of inflammation and pain. This observational study examined the potential involvement of PK2 in degenerative or traumatic knee disease. Fifteen patients presenting knee osteoarthritis (OA group) and 15 patients presenting a traumatic meniscal tear (TM group) were studied. Synovial fluid samples from affected knees were assessed for PK2, IL-10, and TNF-α using the ELISA method. At a long-term follow-up (minimum 5 years, mean = 6.1 years), patients in the TM group underwent clinical re-evaluation with PROMs (Tegner Activity Scale, IKDC, Lysholm, SKV); in addition, X-ray visualization was used to assess the presence of secondary OA. PK2 was detected in synovial fluids of both TM and OA patients and the levels were comparable between the two groups, while IL-10 levels were significantly greater in the OA group than those in TM patients. PK2 levels correlated with those of IL-10. PK2 levels were greater in blood effusions compared to clear samples, did not differ significantly between sexes, nor were they related to differences in weight, height, or injury (meniscal laterality, time since dosing). No correlation was found between PROMs and radiological classifications in patients in the TM group at final follow-up. These data are the first observations of PK2 in synovial fluid following traumatic meniscus injury. These findings suggest possible further prognostic indices and therapeutic targets to limit the development of secondary OA. [ABSTRACT FROM AUTHOR]

Iron(II) bis-pyrazolilpyridyl (bpp-R) complexes [Fe(bpp-R)2](X)2·solvent, R = substituent and X− = anion, can undergo a spin transition from high (S = 2, HS) to low spin (S = 0, LS), being spin crossover (SCO) in the solid state. The distortion of the octahedral coordination environment around the metal centre is governed by crystal packing, i.e. the intermolecular interactions among the substituent R of the bpp-R ligands, the anion X−, and the co-crystallized solvent, and this modulates the SCO behaviour. In this work, an innovative multivariate approach, through the combination of the chemometric tools Principal Component Analysis and Partial Least Squares regression, was applied on the coordination bond distances and angles and selected torsional angles of the available HS structures. The obtained results can efficiently model and rationalize the structural data distinguishing between SCO-active and HS-blocked complexes bearing different R groups, X− anions, and co-crystallized solvents and help predict the spin transition temperature T1/2. [ABSTRACT FROM AUTHOR]

Meniscal lesions in skeletally immature patients can lead to joint degradation and knee instability. Meniscal allograft transplant (MAT) surgery is a solution to maintain knee stability. There is a lack of consensus on MAT surgery outcomes in pediatric patients. A systematic review was conducted according to the PRISMA guidelines. PubMed, Scopus and EMBASE databases were searched from 1965 to June 2022. Studies were evaluated using the Newcastle–Ottawa Scale (NOS). Three studies were selected, and 58 patients were included (mean age 15.9 years) in total. The lateral meniscus was involved in 82.8% of all MAT surgeries. Post-meniscectomy syndrome and discoid meniscus were the main indications for MAT surgery. All studies reported improved subjective clinical scores and levels of sport after the surgery. The complication rate was 27.5%. Partial meniscectomy, meniscus knot removal, chondral defect treatment and lysis of adhesions were the most frequent procedures performed during reoperation. MAT surgery can improve clinical outcomes in pediatric patients with strictly selected indications. MAT surgery is safe when there are no limb asymmetries or malalignments, but it remains a challenging procedure with a high complication rate. Long-term follow-up is needed for definitive statements on the use of MAT in skeletally immature patients. [ABSTRACT FROM AUTHOR]

The tetranuclear iron(III) compounds [Fe4(μ3-O)2(μ-LZ)4] (1–3) were obtained by reaction of FeCl3 with the shortened salen-type N2O2 tetradentate Schiff bases N,N'-bis(salicylidene)-o-Z-phenylmethanediamine H2LZ (Z = NO2, Cl and OMe, respectively), where the one-carbon bridge between the two iminic nitrogen donor atoms guide preferentially to the formation of oligonuclear species, and the ortho position of the substituent Z on the central phenyl ring selectively drives towards Fe4 bis-oxido clusters. All compounds show a flat almost-symmetric butterfly-like conformation of the {Fe4(μ3-O)2} core, surrounded by the four Schiff base ligands, as depicted by both the X-ray molecular structures of 1 and 2 and the optimized geometries of all derivatives as obtained by UM06/6-311G(d) DFT calculations. The strength of the antiferromagnetic exchange coupling constants between the iron(III) ions varies among the three derivatives, despite their magnetic cores remain structurally almost unvaried, as well as the coordination of the metal ions, with a distorted octahedral environment for the two-body iron ions, Feb, and a pentacoordination with trigonal bipyramidal geometry for the two-wing iron ions, Few. The different magnetic behavior within the series of examined compounds may be ascribed to the influence of the electronic features of Z on the electron density distribution (EDD) of the central {Fe4(μ3-O)2} core, substantiated by a Quantum Theory of Atoms In Molecules (QTAIM) topological analysis of the EDD, as obtained by UM06 calculations 1–3. [ABSTRACT FROM AUTHOR]

The incidence of anterior cruciate ligament injuries in skeletally immature patients has increased in recent years. The gold standard treatment of this type of trauma in children is not yet established. Conservative management may underestimate the risk of new meniscal and chondral tears; on the other hand, a more interventional approach may expose the patient to iatrogenic damage to the growth plate. A correct approach to the skeletally immature patient with knee trauma is therefore essential to guide the decision-making process. This review article aims to present an update on the epidemiology and diagnostic process of pediatric patients with anterior cruciate ligament tears and possible associated injuries. Level of Evidence: V. [ABSTRACT FROM AUTHOR]

Osteochondritis dissecans of the knee is a disease that typically affects skeletally immature patients. Clinically manifested with knee pain, limping, and joint disfunction, this condition has remained misunderstood and undervalued for a long period. Although being a rare condition, its awareness is of utmost clinical interest because of the possible severe consequences it can bring when misrecognized or inadequately treated. Its etiology remains unclear and is still debated. Many theories have been proposed, including inflammation, local ischemia, subchondral ossification abnormalities, genetic factors, and repetitive mechanical microtrauma, with a likely interplay of the same. This review article aims to deliver and discuss current and up-to-date concepts on epidemiology, etiology, and natural history of this pediatric condition. Level of evidence : level V. [ABSTRACT FROM AUTHOR]

Background Previous literature has postulated a relationship between greater hamstring stiffness and a higher risk of sustaining injury. Shear wave elastography (SWE) presents a relatively new means for non-invasive evaluation of soft tissue elasticity pre- and post- injury or intervention. Purpose (1) To establish baseline hamstring stiffness measures for young competitive athletes and (2) determine effect of targeted neuromuscular training (TNMT) on shear wave stiffness of the hamstring. Study Design Un-blinded, prospective, non-randomized, cohort study. Methods Six-hundred forty-two lower extremities from 321 high school and collegiate basketball athletes (177 F: 139 M) were examined for hamstring stiffness prior to the start of their competitive basketball season. Teams were cluster assigned to either the control or intervention (TNMT) group. Subjects in the control group underwent regular season activities as directed, with no influence from the research team. For the TNMT group, the research team introduced a hamstring targeted dynamic warm-up program as an intervention focused on activating the hamstring musculature. Results Collegiate status was significant to hamstring stiffness for both sexes (p ≤ 0.02), but hamstring stiffness did not correlate to age or sex (r² ≤ 0.08). Intervention was a significant factor to hamstring stiffness when the hip was positioned in extension (p ≤ 0.01), but not in deeper flexion (p = 0.12). This effect was sex-specific as TNMT influenced hamstring stiffness in females (p = 0.03), but not in males (p ≥ 0.13). Control athletes suffered three HAM injuries; TNMT athletes suffered 0 hamstring injuries. Conclusion Higher SWE measurements correlated with increased risk of injury, male sex, and collegiate athletics. TNMT intervention can lessen muscle stiffness which may reduce relate to injury incidence. Intervention effectiveness may be sex specific. [ABSTRACT FROM AUTHOR]

With regards to oil-based diesel fuel, the adoption of bio-derived diesel fuel was estimated to reduce CO2 emissions by approximately 75%, considering the whole life cycle. In this paper, we present a novel continuous-flow process able to transfer an equimolar amount of CO2 (through urea) to glycerol, producing glycerol carbonate. This represents a convenient tool, able to both improve the efficiency of the biodiesel production through the conversion of waste streams into added-value chemicals and to beneficially contribute to the whole carbon cycle. By means of a Design of Experiments approach, the influence of key operating variables on the product yield was studied and statistically modeled. [ABSTRACT FROM AUTHOR]

Copper(II) complexes of salen analogues in which the two salicylaldehyde moieties carry different substituents in position 5, producing a push-pull charge asymmetry are presented. The results obtained from the first principles calculations have provided a reliable description of both structural and excited-state properties of the complexes, as well as of their nonlinear optical (NLO) properties.

There is a lack of molecular probes for imaging bacteria, in comparison to the array of such tools available for the imaging of mammalian cells. Here, organometallic molecular probes have been developed and assessed for bacterial imaging, designed to have the potential to support multiple imaging modalities. The chemical structure of the probes is designed around a metal-naphthalimide structure. The 4-amino-1,8-naphthalimide moiety, covalently appended through a pyridine ancillary ligand, acts as a luminescent probe for super-resolution microscopy. On the other hand, the metal centre, rhenium(I) or platinum(II) in the current study, enables techniques such as nanoSIMS. While the rhenium(I) complex was not sufficiently stable to be used as a probe, the platinum(II) analogue showed good chemical and biological stability. Structured illumination microscopy (SIM) imaging on live Bacillus cereus confirmed the suitability of the probe for super-resolution microscopy. NanoSIMS analysis was used to monitor the uptake of the platinum(II) complex within the bacteria and demonstrate the potential of this chemical architecture to enable multimodal imaging. The successful combination of these two moieties introduces a platform that could lead to a versatile range of multi-functional probes for bacteria. [ABSTRACT FROM AUTHOR]

The copper(II) complexes of general formula [Cu(GL)(Cl)] (1–3, G = OMe, H and NO2, respectively), bearing tridentate Schiff base ligands (GL−) and a chloride as a fourth labile one, are here reported. The Schiff bases derive from the monocondensation of ethylenediamine and substituted salicylaldehyde, where the electronic properties are modulated by the releasing or withdrawing power of the G group. The compounds were structurally characterized through single crystal Synchrotron X-ray diffraction experiments in the solid state, revealing that 1 (OMe) and 2 (H) adopt a dimeric assembly [Cu(μ-Cl)(GL)]2 through apical interaction of the chloride ions of two monomeric units, while 3 embraces a 1D polymeric chain structure [Cu(μ-Cl)(NO2L)]n with a similar bridging fashion, all supported by extended intramolecular or intrachain hydrogen bonds. The redox properties of the complexes were also studied by cyclic voltammetry with no marked effect of the substituent on the potential of the CuII/CuI redox system. UV/Vis spectroscopic studies in mimicked physiological conditions highlighted the intactness and stability of the coordinated NNO tridentate ligand in 1–3 and the lability of the coordinated chloride ion with the formation of the aquo-complexes [Cu(GL)(H2O)]+ in aqueous solution, as confirmed by conductance measurements with a 1 : 1 electrolyte molar conductivity. In vitro tests on cell viability were conducted on malignant cell lines typical for their poor prognosis and curability, revealing time-dependent and differential cytotoxicity given by the substituent G. All compounds were capable of formation of intracellular reactive oxygen species and DNA intercalation, acting as nuclease and producing double-strand DNA breaks. This is especially effective for 3 (NO2), which revealed the highest anticancer activity against malignant triple-negative breast cancer MDA-MB-231 cells, with a two-to-four-fold cytotoxicity enhancement with respect to 1 (OMe) and 2 (H), and, most important, substantial differentiation of cytotoxicity with respect to healthy endothelial HUVEC cell line. [ABSTRACT FROM AUTHOR]

The syntheses of dipolar alkynylruthenium complexes with oligo(phenyleneethynylene) bridges, together with those of precursor alkynes, complexes with the donor-[pi]-bridge-acceptor formulation that has afforded efficient quadratic and cubic NLO compounds are reported. The quadratic nonlinearity [[beta].sub.1064] and two-photon absorption cross-section has reached maximal values at this same [pi]-bridge length, a similar saturation behavior that has reflected a common importance of ruthenium-to-alkynyl ligand charge transfer in electronic and optical behavior in these molecules.

New push–pull (A–D) nickel(ii) compounds of general formula [Ni(5-A-5′-D-saltn)] (3a–3l) with unsymmetrically-substituted N2O2 tetradentate Schiff base ligands are reported here. The ligands 5-A-5′-D-saltn2− (H2saltn = N,N′-bis(salicylidene)diaminopropane) possess differently-substituted salicylaldehyde (A/Dsal) moieties condensed to 1,3-diaminopropane (tn), and carry either an electron acceptor (A = H, Br, or NO2) or donor (D = H, Me, or OMe) group in the para position with respect to the coordinated phenoxido oxygen atoms. These compounds could be obtained by template synthesis involving derivatives [Ni(Gsal)2(H2O)2], 1a–e (G = NO2, Br, H, Me and OMe, respectively) and [Ni(GL)2], 2a–d (GL− = (E)-2-((3-aminopropylimino)methyl)-4-G-phenolate, G = NO2, Br, H and Me, respectively). Scrambling of the ligands and condensation to compounds 3 was suitably achieved by refluxing compounds 1 and 2 that carry the G groups suitable for the desired final A–D combination. Dinuclear intermediates [Ni2(μ-GL)2(G′sal)2] (4a,b,e,f,g) were also detected and isolated. The single-crystal X-ray diffraction structures of [Ni(5′-OMe-saltn)]·CHCl3 (3c·CHCl3), [Ni(5-Br-5′-OMe-saltn)]·EtOH (3g·EtOH) and [Ni(5-NO2-saltn)] (3j) show different degrees of distortion around the central core, leading to saddle-like (3c), planar (3g) and step-like (3j) molecular conformations. DFT geometrical optimization of the compounds showed that, for isolated molecules, the saddle-like conformation is slightly more stable with respect to the other conformations. UV-visible absorption spectra showed structured absorption profiles at about 320–440 nm, whose intensity was amplified by the presence of the nitro group, and this was assigned to a convolution of one metal-to-ligand charge transfer and two intra-ligand charge transfer transitions by TDDFT computations. Surprisingly, UV-visible spectra of the derivatives with Br were comparable to the derivatives with Me, suggesting that in this case the behaviour of the halogen was as a weak electron donor group. The experimental investigation (through electric-field-induced second-harmonic and solvatochromic measurements) of the second-order NLO responses of compounds 3, in conjunction with the theoretical calculations, revealed that the observed NLO efficiency is determined by the combined effect of two almost orthogonal charge transfer directions within the molecules, one along the axis approximately bisecting the donor and the accepting moieties and the other along the A–D axis. [ABSTRACT FROM AUTHOR]

In continuation of our work on supramolecular architectures of single-molecule magnets (SMMs) as a promising strategy in developing their magnetic performance, in this paper we report the synthesis and single crystal X-ray structure of the centered triangular tetrairon(III) SMM, [Fe4(PhpPy)2(dpm)6], Fe4 (Hdpm = dipivaloylmethane, H3PhpPy = 2-(hydroxymethyl)- 2-(4-(pyridine-4-yl)phenyl)propane-1,3-diol), and its assembly in the coordination polymer {[Fe4(PhpPy)2(dpm)6Ag](ClO4)}n, Fe4Ag, upon reaction with silver(I) perchlorate. Thanks to the presence of the pyridyl rings on the two tripodal ligands, Fe4 behaves as divergent ditopic linker, and due to the Fe4:AgClO4 1:1 ratio, Fe4Ag probably possesses a linear arrangement in which silver(I) ions are linearly coordinated by two nitrogen atoms, forming 1D chains whose positive charge is balanced by the perchlorate anions. The stabilization of such a polymeric structure can be ascribed to the long distance between the two donor nitrogen atoms (23.4 Å) and their donor power. Fe4Ag shows slow relaxation of the magnetization which follows a thermally activated process with Ueff/kB = 11.17(18) K, τ0 = 2.24(17) 10-7 s in zero field, and Ueff/kB = 14.49(5) K, t0 = 3.88(8) 10-7 s in 1-kOe applied field, in line with what reported for tetrairon(III) SMMs acting as building blocks in polymeric structures. [ABSTRACT FROM AUTHOR]

The treatment of anterior cruciate ligament (ACL) injuries in children and adolescents is challenging. Preclinical and clinical studies investigated ACL repairing techniques in skeletally immature subjects. However, intra-articular bioenvironment following ACL tear has not yet been defined in skeletally immature patients. The aim of this study was to measure cytokine concentrations in the synovial fluid in adolescent population. Synovial levels of IL-1β, IL-1ra, IL-6, IL-8, IL-10, and TNF-α were measured in 17 adolescent patients (15 boys) with ACL tears who underwent ACL reconstruction including acute (5), subacute (7), and chronic (5) phases. Femoral growth plates were classified as “open” in three patients, “closing” in eight, and “closed” in six. Eleven patients presented an ACL tear associated with a meniscal tear. The mean Tegner and Lysholm scores (mean±SD) of all patients were 8 ± 1 and 50.76 ± 26, respectively. IL-8, TNF-α, and IL-1β levels were significantly greater in patients with “open” physes. IL-1ra and IL-1β levels were significantly higher in patients with ACL tear associated with a meniscal tear. Poor Lysholm scores were associated with elevated IL-6 and IL-10 levels. IL-10 levels positively correlated with IL-6 and IL-8 levels, whereas TNF-α concentration negatively correlated with IL-6 levels. Skeletally immature patients with meniscal tears and open growth plates have a characteristic cytokine profile with particularly elevated levels of proinflammatory cytokines including IL-8, TNF-α, and IL-1β. This picture suggests that the ACL tear could promote an intra-articular catabolic response in adolescent patients greater than that generally reported for adult subjects. The study lacks the comparison with synovial samples from healthy skeletally immature knees due to ethical reasons. Overall, these data contribute to a better knowledge of adolescent intra-articular bioenvironment following ACL injuries. [ABSTRACT FROM AUTHOR]

Abstract: The homoleptic mononuclear compound [Co(bpp‐COOMe)2](ClO4)2 (1) (bpp‐COOMe=methyl 2,6‐di(pyrazol‐1‐yl)pyridine‐4‐carboxylate) crystallizes in the monoclinic C2/c space group, and the cobalt(II) ion possesses a pseudo‐octahedral environment given by the two mer‐coordinated tridentate ligands. Direct‐current magnetic data, single‐crystal torque magnetometry, and EPR measurements disclosed the easy‐axis nature of this cobalt(II) complex, which shows single‐molecule magnet behavior when a static field is applied in alternating‐current susceptibility measurements. Diamagnetic dilution in the zinc(II) analogue [Zn(bpp‐COOMe)2](ClO4)2 (2) afforded the derivative [Zn0.95Co0.05(bpp‐COOMe)2](ClO4)2 (3), which exhibits slow relaxation of magnetization even in zero field thanks to the reduction of dipolar interactions. Theoretical calculations confirmed the overall electronic structure and the magnetic scenario of the compound as drawn by experimental data, thus confirming the spin‐phonon Raman relaxation mechanism, and a direct quantum tunneling in the ground state as the most plausible relaxation pathway in zero field. [ABSTRACT FROM AUTHOR]

The metal complexing ability in solution of four substituted curcumin (CUR)-derived ligands K3T, originated by the insertion of the –CH2CH2COOtBu branch on the central atom of the diketonic moiety of CUR and related derivatives with variable meta and para substituents (OH, OMe, H, OCOCH3) on the peripheral aromatic rings, is examined. These molecules can act as new chelators with biological properties comparable to those of CUR but with improved stability. In fact, curcuminoids represent new perspectives for the development of novel therapeutic agents for several diseases including Alzheimer's disease. CUR showed neuroprotective properties, and a probable mechanism of its action is related to the complexation ability towards endogenous metal ions Fe3+ and Cu2+. K3T derivatives retain the solvent-dependent diketo–ketoenol tautomerism, with the prevalence of the diketonic form in aqueous solution. They show enhanced stability in simulated physiological conditions (phosphate buffered solution at pH = 7.4) compared to CUR, together with similar or even higher anti-proliferative activity against human colon carcinoma cells HCT116. The addition of the metal ion causes dissociation of the enolic proton creating chelate complexes and shift of the tautomeric equilibrium toward the keto–enol species. The formation of metal complexes was followed and confirmed by both NMR (using Ga3+ as a diamagnetic probe for Fe3+) and UV-visible spectroscopy. All the ligands showed high affinity for Fe3+ and Ga3+, forming M : L 1 : 2 species. In view of therapeutic applications, notable is the good affinity of K3T31, i.e. the ligand bearing only OH groups in para positions of the aromatic rings, for Cu2+, and the ability of the Cu : K3T31 1 : 1 complex to bind to DNA. [ABSTRACT FROM AUTHOR]

A combined experimental and theoretical study on the molecular structure of linear trinuclear nickel compounds of general formula [Ni 3 (μ- Z saltn) 2 (μ-AcO) 2 (S) 2 ] (Z = H, 1S , and Br, 2S , where S identifies coordinated solvent molecules) is here presented. In these complexes the three metal ions are linked together by bridging acetato ions and tetradentate Schiff base ligands, these last derived from the condensation of 1,3-diaminopropane with two equivalents of 5-Z-salicylaldehyde. Two solvent molecules S can also interact with the terminal nickel ions to complete an octahedral coordination environment. We report the synthesis of [Ni 3 (μ- Br saltn) 2 (μ-AcO) 2 ] ( 2 ), and its crystal structure with two coordinated dimethylformamide molecules, [Ni 3 (μ- Br saltn) 2 (μ-AcO) 2 (DMF) 2 ] ( 2DMF ). Its comparison with the crystal structure of 2 without solvent, together with the series of compounds 1 , 1DMF , 1MeOH , 1DMSO , 1Py and 1H 2 O (MeOH = methanol, DMSO = dimethylsulfoxide, Py = pyridine) available in the literature, allows recognising modification in Ni O and Ni N coordination bond lengths and peculiar intermolecular contacts between neighbour molecules. In order to discern among the contribution of solvent molecules, crystal packing and substituent Z (H or Br) on bond distances (and angles), we performed a systematic theoretical study on four representative derivatives, namely 1 , 1DFM , 2 and 2DMF , with the M06 functional and a careful choice of the best basis set. The results indicate that, while the major modulating factor is the presence or absence of the sixth solvent molecule to the peripheral nickel(II) ion, even if less strongly coordinated with Ni O/N bond distances > 2.15 Å, π-π stacking interactions and C H⋯π and/or C Br⋯π non-bonded interactions affect the coordination geometry in a significant way. [ABSTRACT FROM AUTHOR]

Beneficial effects in bone cell growth and antibacterial action are currently attributed to Ga3+ ions. Thus, they can be used to upgrade mesoporous bioactive glasses (MBGs), investigated for tissue engineering, whenever they released therapeutic amounts of gallium ions to the surrounding medium. Three gallium-enriched MBGs with composition (in mol %) xSiO2-yCaO-zP2O5-5Ga2O3, being x = 70, y = 15, z = 10 for Ga_1; x = 80, y = 12, z = 3 for Ga_2; and x = 80, y = 15, z = 0 for Ga_3, were investigated and compared with the gallium-free 80SiO2-15CaO-5P2O5 MBG (B). 29Si and 31P MAS NMR analyses indicated that Ga3+ acts as network modifier in the glass regions with higher polymerization degree and as network former in the zones with high concentration of classical modifiers (Ca2+ ions). Ga_1 and Ga_2 exhibited a quick in vitro bioactive response because they were coated by an apatite-like layer after 1 and 3 days in simulated body fluid. Although we have not conducted biological tests in this paper (cells or bacteria), Ga_1 released high but non-cytotoxic amounts of Ga3+ ions in Todd Hewitt Broth culture medium that were 140 times higher than the IC90 of Pseudomonas aeruginosa bacteria, demonstrating its potential for tissue engineering applications. [ABSTRACT FROM AUTHOR]

The molecular structures and magnetic properties of homoleptic iron(ii) compounds [Fe(bpp-COOMe)2](ClO4)2 (1) and [Fe(bpp-triolH3)2](ClO4)2 (2) have been investigated to ascertain their spin crossover (SCO) behaviour. In these hexacoordinated complexes, the bpp (2,6-bis(pyrazol-1-yl)pyridine) ligands adopt a mer–mer coordination mode and carry COOMe or C(O)NHC(CH2OH)3para substituents, respectively, on the central pyridyl ring. In spite of the almost equal donor power of the ligands to the iron(ii) centre, the two compounds feature different spin state configurations at room temperature. Compound 1 displays a highly-distorted octahedral environment around the iron(ii) centre, which adopts a high spin (HS) state at all temperatures, even under an external applied pressure up to 1.0 GPa. By contrast, 2 is characterized by a more regular octahedral coordination around the metal ion and exhibits a low spin (LS) configuration at or below room temperature. However, it shows a thermally-induced SCO behaviour at T ＞ 400 K, along with Light-Induced Excited Spin State Trapping (LIESST) at low temperature, with TLIESST = 38 K. Since DFT (U)M06/6-311+G(d) geometry optimizations in vacuo indicate that both complexes should adopt a HS state and a highly-distorted coordination geometry, the stabilization of a LS configuration in 2 is ultimately ascribed to the effect of intermolecular hydrogen bonds, which align the [Fe(bpp-triolH3)2]2+ cations in 1D chains and impart profound differences in the geometric arrangement of the ligands. [ABSTRACT FROM AUTHOR]

A 3D metal-organic framework (MOF) having single-molecule magnet (SMM) linkers was prepared in crystalline form by using a tetrairon(III) complex functionalised with two divergent pyridyl groups, namely [Fe4(pPy)2(dpm)6] ( 1; H3pPy=2-(hydroxymethyl)-2-(pyridin-4-yl)propane-1,3-diol, Hdpm=dipivaloylmethane). Reaction of 1 with silver(I) perchlorate afforded {[Fe4(pPy)2(dpm)6]2Ag}ClO4 ( 2), which crystallises in a cubic face-centred lattice and exhibits two interlocked diamondoid networks. In 2, the SMMs act as linear ditopic synthons, and silver(I) ions as tetrahedral nodes coordinated by four pyridyl nitrogen atoms. The magnetic properties of 1 ( S=5 and D≈−0.4 cm−1 in the ground spin state) are largely preserved in 2, which shows slow magnetic relaxation with an anisotropy barrier of Ueff/ kB=11.46(10) K in zero field and 14.25(8) K in an applied field of 1 kOe. However, crystal symmetry triggers highly noncollinear magnetic anisotropy contributions oriented at 109.47° from each other along the threefold axes of AgN4 tetrahedra, a unique scenario fully confirmed by a single-crystal cantilever torque magnetometry investigation. Magnetisation curves down to 0.03 K demonstrated the occurrence of a wide hysteresis loop when the magnetic field was swept along one of the four Ag−N bonds. By symmetry, the crystalline compound can then be persistently magnetised parallel or antiparallel to the four main diagonals of the unit cell, although the crystals have no overall second-order anisotropy. [ABSTRACT FROM AUTHOR]

Compounds [Fe3Ln(tea)2(dpm)6] ( Fe3Ln; Ln= Tb-Yb, H3tea=triethanolamine, Hdpm=dipivaloylmethane) were synthesized as lanthanide(III)-centered variants of tetrairon(III) single-molecule magnets (Fe4) and isolated in crystalline form. Compounds with Ln=Tb-Tm are isomorphous and show crystallographic threefold symmetry. The coordination environment of the rare earth, given by two tea3− ligands, can be described as a bicapped distorted trigonal prism with D3 symmetry. Magnetic measurements showed the presence of weak ferromagnetic Fe ⋅⋅⋅Ln interactions for derivatives with Tb, Dy, Ho, and Er, and of weak antiferromagnetic or negligible coupling in complexes with Tm and Yb. Alternating current susceptibility measurements showed simple paramagnetic behavior down to 1.8 K and for frequencies reaching 10000 Hz, despite the easy-axis magnetic anisotropy found in Fe3Dy, Fe3Er, and Fe3Tm by single-crystal angle-resolved magnetometry. Relativistic quantum chemistry calculations were performed on Fe3Ln (Ln=Tb-Tm): the ground J multiplet of Ln3+ ion is split by the crystal field to give a ground singlet state for Tb and Tm, and a doublet for Dy, Ho, and Er with a large admixture of mJ states. Gyromagnetic factors result in no predominance of gz component along the threefold axis, with comparable gx and gy values in all compounds. It follows that the environment provided by the tea3− ligands, though uniaxial, is unsuitable to promote slow magnetic relaxation in Fe3Ln species. [ABSTRACT FROM AUTHOR]

Tetrairon(III) single-molecule magnets [Fe4(pPy)2(dpm)6] ( 1) (H3pPy=2-(hydroxymethyl)-2-(pyridin-4-yl)propane-1,3-diol, Hdpm=dipivaloylmethane) have been deliberately organized into supramolecular chains by reaction with RuIIRuII or RuIIRuIII paddlewheel complexes. The products [Fe4(pPy)2(dpm)6][Ru2(OAc)4](BF4)x with x=0 ( 2 a) or x=1 ( 2 b) differ in the electron count on the paramagnetic diruthenium bridges and display hysteresis loops of substantially different shape. Owing to their large easy-plane anisotropy, the s=1 diruthenium(II,II) units in 2 a act as effective seff=0 spins and lead to negligible intrachain communication. By contrast, the mixed-valent bridges ( s=3/2, seff=1/2) in 2 b introduce a significant exchange bias, with concomitant enhancement of the remnant magnetization. Our results suggest the possibility to use electron transfer to tune intermolecular communication in redox-responsive arrays of SMMs. [ABSTRACT FROM AUTHOR]