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Three new polycatenated mixed-ligand MOFs containing fluorene and naphthalene scaffolds have been solvothermally synthesized. Their solid-state luminescence has been investigated showing a Förster resonance energy transfer involving the two linkers.

Protein pool turnover is a critically important cellular homeostatic component, yet it has been little explored in the context of heart failure (HF) pathophysiology. We employed in vivo 2H labeling/ proteome dynamics for non-biased discovery of turnover alterations involving functionally linked cardiac and plasma proteins in canine tachypacing-induced HF, an established preclinical model of dilated cardiomyopathy. Compared to control, dogs with congestive HF displayed bidirectional turnover changes of 28 cardiac proteins, i.e. reduced half-life of several key enzymes involved in glycolysis, homocysteine metabolism and glycogenesis, and increased half-life of proteins involved in proteolysis. Changes in plasma proteins were more modest: only 5 proteins, involved in various functions including proteolysis inhibition, hemoglobin, calcium and ferric-iron binding, displayed increased or decreased turnover rates. In other dogs undergoing cardiac tachypacing, we infused for 2 weeks the myokine Follistatin-like protein 1 (FSTL1), known for its ameliorative effects on HF-induced alterations. Proteome dynamics proved very sensitive in detecting the partial or complete prevention, by FSTL1, of cardiac and plasma protein turnover alterations. In conclusion, our study unveiled, for the first time in a large mammal, numerous HF-related alterations that may serve as the basis for future mechanistic research and/or as conceptually new molecular markers.

In this work, unprecedented {dz2-CuIIO4}⋯π-hole interactions are described in the case of a cocrystal of a Cu(ii) bis-β-diketonate complex and 1,4-diiodotetrafluoro-benzene.

The highest degree of interpenetration reported so far of 7- and 8-fold is realized in two luminescent sql 2D networks by self-assembly of a new nanometric-sized ligand with Ag(i) salts.

The different nature of the emissive states of AgI and CuI one- and three-dimensional coordination polymers is here explained by a higher covalent character of the Cu—N bond with respect to the Ag—N one., A QTAIM and IQA investigation on model compounds of two isostructural AgI and CuI coordination polymers (CPs) based on cyclic tri­imidazole (L), i.e. the [MIL] n 1D double-stranded stair chain and the [MClL] n 3D network (M = Cu, Ag), has allowed light to be shed on the different emissive behaviour associated with the two metal ions. According to a previously reported investigation [Malpicci et al. (2021). Inorg. Chem. Front. 8, 1312–1323 ▸], AgI CPs showed both fluorescence and multiple ligand-centred room-temperature phospho­rescences, whereas CuI CPs displayed non-thermally equilibrated halogen and metal-to-ligand charge transfer and two ligand-centred phospho­rescences, the latter observed only by their selective activation. Analysis of both local and integral QTAIM descriptors, including delocalization indices and source function, of the Ag—N and Cu—N bonds reveals a higher covalent and local character for the latter, explaining the greater metal–ligand electronic communication observed for the Cu compounds. Moreover, IQA investigation shows that the Cu—N bond is characterized by higher interaction energy, due to both higher electrostatic and exchange-correlation contributions. Analysis on the M—X (M = Ag, Cu; X = I, Cl) bonds, also present in these structures, highlights a much higher covalent and local character with respect to the M—N bonds.

To what extent cardiac renewal occurs in adulthood and can be stimulated by therapeutic interventions is still a matter of investigation. In particular, over the last few years, significant effort has been made into awakening the endogenous regenerative potential of the adult mammalian heart after injury using different strategies. However, these studies are significantly hindered by the lack of tools to properly assess cardiomyocyte renewal over time. We have developed a genetic strategy, which we named CycleTrack, allowing a cumulative and accurate estimate of cardiomyocyte divisions in vivo. This method is based on the expression, in cardiomyocytes, of the Cre recombinase under the control of a 312-bp fragment of the Cyclin B2 promoter, which is specifically sensitive to cell proliferation. Replication-activated Cre acts on floxed GFP that is either present in the genome of transgenic mice or is exogenously delivered using Adeno-Associated Viral (AAV) vectors. As a result, cardiomyocytes traversing G2/M become irreversibly labeled. Using CycleTrack, we could monitor cardiomyocyte turnover in several physiological and pathological conditions. These included the measurement of the rate of proliferation of cardiomyocytes after apical resection in neonatal mice, the pro-regenerative effect of AAV9-mediated delivery of miRNA-199a and miRNA-590 after myocardial infarction in adult mice and the effect of pregnancy on myocardial hyperplasia. We also delivered the CycleTrack vectors into pig hearts to visualize cardiomyocyte turnover after myocardial infarction. Considering the large availability of Cre reporter mouse lines and the efficacy of AAVs to transfer genes into cardiomyocytes, we propose CycleTrack as a robust and straightforward tool to trace mitotic events for cardiac regeneration studies in small and large animal models.

Cocrystallization of a bis[1-(4-pyridyl)butane-1,3-dionato]copper(II) (1) complex and 1,4-diiodoperfluorobenzene in the presence of pyridine yields a 1 : 1 cocrystal where both the σ and π-holes of 1,4-diiodoperfluorobenzene play a role. The crystal structure shows short arene CuO

Purely organic luminophores that exhibit room temperature phosphorescence (RTP) are receiving an ever-growing attention. The design of efficient RTP materials and the understanding of their emissive behaviour, however, remain a challenging task. Herein, to gain further insights into metal-free RTP, we report the synthesis, characterization, and photophysical study of chloro-derivatives of [1,2-a:1',2'-c:1'',2''-e][1,3,5]triazine or cyclic triimidazole (TT). Mono-(1Cl), di-(2Cl) and tri-chloro-TT (3Cl) derivatives are prepared by mild chlorination with N-chlorosuc-cinimide (NCS). The three compounds are characterized by aggregation-induced emission (AIE) comprising dual fluorescence and multiple phosphorescences, whose origin is disclosed by crystal structure analysis together with accurate DFT/TDDFT calculations. Comparison with previously reported bromine and iodine TT derivatives reveals the new chlorinated compounds as the best performing halogenated AIE members of the family.

The remarkable emissive properties of cyclic triimidazole (TT), showing crystallization-induced emissive behavior and, in particular, room temperature phosphorescence (RTP), are here combined with its versatility in assembling coordination compounds. A series of Ag(I) coordination polymers (CPs), comprising a 1D chain ([Ag(TT)I]n, 1-Ag) and 3D networks ([Ag(TT)Cl]n, 2-Ag, and [Ag3(TT)4]n(NO3)3n·6nH2O, 3-Ag), have been synthesized and their photophysical behavior thoroughly investigated. They show both fluorescence and multiple RTPs, all simultaneously activated but varied in intensity by changing the excitation energy. Based on DFT/TDDFT calculations and analysis of the X-ray crystal structures, the origin of the different phosphorescences has been ascribed to H-aggregation of the ligand (in 1-Ag and 2-Ag), intermolecular electronic coupling by an extrinsic heavy-atom effect (in 1-Ag) and ligand-centered emissive states (in all three compounds). Comparison with isostructural 1-Cu and 2-Cu CPs reveals that, different from the Ag(I) analogues, non-thermally equilibrated XMLCT and ligand-centered emissive states are active. The isostructural Ag(I) and Cu(I) compounds show comparable emission efficiency, while the phosphorescence lifetimes are longer for the former (ms regime) than the latter (micro-s regime). A Quantum Theory of Atoms In Molecules (QTAIM) topological analysis of electron density allows the interpretation of the different nature of the emissive states of Ag(I) and Cu(I) compounds on the basis of larger shell-shared character of the Cu-N bond with respect to the Ag-N one.

Mixed multidentate linkers with donor groups of different types can be fruitfully exploited in the self-assembly of coordination polymers (CPs) and Metal-Organic Frameworks (MOFs). In this work we develop new ligands containing a β-diketone chelating functionality, to better control the stereochemistry at the metal center, and tetrazolyl multidentate bridging groups, a combination not yet explored for networking with metal ions. The new ligands, 1,3-bis(4-(1H-tetrazol-5-yl)phenyl)-1,3-propanedione (H3L1) and 1-phenyl-3-(4-(1H-tetrazol-5-yl)phenyl)-1,3-propanedione (H2L2), are synthesized from the corresponding nitrile precursors by [2+3] dipolar cycloaddition of azide under metal-free catalytic conditions. Crystal structure analysis evidences the involvement of tetrazolyl fragments in multiple hydrogen bonding giving 2D and 1D supramolecular frameworks. Reactivity of the new ligands with different metal salts indicates good coordinating ability, and we report the preparation and structural characterization of the tris–chelate complex [Fe(HL1)3]3− (1) and the homometallic 2D CP [ZnL2(DMSO)] (2). In compound 1 only the diketonate donor is used, whereas the partially deprotonated tetrazolyl groups are involved in hydrogen bonding, giving rise to a 2D supramolecular framework of (6,3)IIa topological type. In compound 2 the ligand is completely deprotonated and uses both the diketonate donor (chelating) and the tetrazolate fragment (bridging) to coordinate the Zn(II) ions. The resulting neutral 2D network of sql topology shows luminescence in the solid state, which is red shifted with respect to the free ligand. Interestingly, it can be easily exfoliated in water to give a luminescent colloidal solution.

Organic materials with multiple emissions tunable by external stimuli represent a great challenge. TTPyr, crystallizing in different polymorphs, shows a very rich photophyisics comprising excitation-dependent fluorescence and phosphorescence at ambient conditions, and mechanochromic and thermochromic behavior. Transformation among the different species has been followed by thermal and X-ray diffraction analyses and the emissive features interpreted through structural results and DFT/TDDFT calculations. Particularly intriguing is the polymorph TTPyr(HT), serendipitously obtained at high temperature but stable also at room temperature, whose non-centrosymmetric structure guarantees an SHG efficiency 10 times higher than that of standard urea. Its crystal packing, where only the TT units are strongly rigidified by π-π stacking interactions while the Pyr moieties possess partial conformational freedom, is responsible for the observed dual fluorescence. The potentialities of TTPyr for bioimaging have been successfully established.

Colemanite is a natural borate that can be used as an aggregate in neutron-radiation shielding concretes. In this study, we report its thermal behavior, up to 500 °C, by describing: 1) its dehydration mechanisms and 2) its thermo-elastic parameters. The thermal expansion of colemanite is significantly anisotropic. The refined volume thermal expansion coefficient at ambient conditions is: αV0 = 4.50(10)·10−5 K−1. The loss of structural H2O occurs at least from ∼240 °C, and at T > 325 °C an irreversible amorphization occurs, followed by a complete dehydration. The potential implications on the use of colemanite as concrete-aggregate are discussed.

Herein, four different coordination networks were isolated and structurally characterized by combining two aminocarboxylate ligands, 4,4′-[biphenyl-4,4′-diylbis(azanediyl)]dibenzoic acid and 5,5′-[biphenyl-4,4′-diylbis(azanediyl)]diisophthalic acid (H2L1 and H4L2, respectively), with different transition metals (Zn(II), Zr(IV) and Cd(II)) under solvothermal conditions. The reaction between H2L1 and Zn(NO3)2·6H2O led to two different coordination networks. In PUMflex1-Zn, which has the formula {[Zn4O(L1)3(DMF)2](DMF)5}n·(DMF)x, the ligand always displays a syn conformation (with respect to the central biphenylene scaffold), whereas in the polymorph PUMflex1.1-Zn, one of the three ligands composing the asymmetric unit adopts an anti conformation. Although the two supramolecular isomers have equivalent stoichiometry and dimensionality, they show different topologies and entanglement types: parallel polycatenation of the 63-hcb and 2-fold interpenetration of the 44-sql layers, respectively. In the case of PUMflex1-Zr, with the formula {[Zr6O4(OH)8(L1)4(H2O)2]n·(DMF)x, H2L1 exclusively adopts the syn conformation, forming 1D-chains of rugby-ball shaped aggregates (topological type 2,8C1) interconnected through H-bonds with water molecules. In contrast, H4L2 behaves as a dianionic ligand in PUMflex2-Cd, with the formula [Cd(κ2-COO)2(DMF)3(DMF)]n, forming 1D zig-zag chains connected through the N–H⋯OC(OH) H-bonds to provide planar layers of sql topology. In all cases, the ability of the amine functions to interact with the H-bond active guests is structurally highlighted by the recurrent N–H⋯ODMF interaction modelled in the X-ray structures.

Dramatic advances in nanostructured MOFs have been strongly promoted by the introduction and development of new synthetic methods that control the size, morphology, and nano/microstructure. High intensity ultrasound method suggests an environmentally friendly, facile and versatile synthetic method to these nanostructured materials that are complicated to synthesize by commonly used methods. Both Solvothermal and sonochemical methods were used to synthesize the new urea-based metal-organic framework [Cd(L1)(DMF)3] (1). Compound 1 was structurally characterized by using X-ray crystallography and spectroscopically by different techniques. The effect of concentration of the initial reagents, time of sonication and sonication power on size and morphology has been studied. The results indicate that decreasing concentration of initial reagents, along with increasing ultrasonic radiation time, cause a dramatic effect on the size and morphology of compound 1. Calcination of the nano-sized plate-like particles of compound 1 at 550 °C under air atmosphere yields CdO nanoparticles.

Objective. Bioelectronic medicine is an emerging field that aims at developing closed-loop neuromodulation protocols for the autonomic nervous system (ANS) to treat a wide range of disorders. When designing a closed-loop protocol for real time modulation of the ANS, the computational execution time and the memory and power demands of the decoding step are important factors to consider. In the context of cardiovascular and respiratory diseases, these requirements may partially explain why closed-loop clinical neuromodulation protocols that adapt stimulation parameters on patient’s clinical characteristics are currently missing. Approach. Here, we developed a lightweight learning-based decoder for the classification of cardiovascular and respiratory functional challenges from neural signals acquired through intraneural electrodes implanted in the cervical vagus nerve (VN) of five anaesthetized pigs. Our algorithm is based on signal temporal windowing, nine handcrafted features, and random forest (RF) model for classification. Temporal windowing ranging from 50 ms to 1 s, compatible in duration with cardio-respiratory dynamics, was applied to the data in order to mimic a pseudo real-time scenario. Main results. We were able to achieve high balanced accuracy (BA) values over the whole range of temporal windowing duration. We identified 500 ms as the optimal temporal windowing duration for both BA values and computational execution time processing, achieving more than 86% for BA and a computational execution time of only ∼6.8 ms. Our algorithm outperformed in terms of BA and computational execution time a state of the art decoding algorithm tested on the same dataset (Vallone et al 2021 J. Neural Eng. 18 0460a2). We found that RF outperformed other machine learning models such as support vector machines, K-nearest neighbors, and multi-layer perceptrons. Significance. Our approach could represent an important step towards the implementation of a closed-loop neuromodulation protocol relying on a single intraneural interface able to perform real-time decoding tasks and selective modulation of the VN.

Anion recognition by neutral hosts that function in aqueous solution is an emerging area of interest in supramolecular chemistry. The design of neutral architectures for anion recognition still remains a challenge. Among neutral anion receptor systems, urea and its derivatives are considered as "privileged groups" in supramolecular anion recognition, since they have two proximate polarized N-H bonds exploitable for anion recognition. Despite promising advancements in urea-based structures, the strong hydrogen bond drives detrimental self-association. Therefore, immobilizing urea fragments onto the rigid structures of a metal-organic framework (MOF) would prevent this self-association and promote hydrogen-bond-accepting substrate recognition. With this aim, we have synthesized two new urea-containing metal-organic frameworks, namely [Zn(bpdc)(L2)]n·nDMF (TMU-67) and [Zn2(bdc)2(L2)2]n·2nDMF (TMU-68) (bpdc = biphenyl-4,4'-dicarboxylate; bdc = terephthalate; L2 = 1,3-bis(pyridin-4-yl)urea), and we have assessed their recognition ability toward different anions in water. The two MOFs show good water stability and anion affinity, with a particular selectivity toward dihydrogen arsenate for TMU-67 and toward fluoride for TMU-68. Crystal structure characterizations reveal 3-fold and 2-fold interpenetrated 3D networks for TMU-67 and TMU-68, respectively, where all single interpenetrated networks are hydrogen bonded to each other in both cases. Despite the absence of self-quenching, the N-H urea bonds are tightly hydrogen bonded to the oxygen atoms of the dicarboxylate ligands and cannot be directly involved in the recognition process. The good performance in anion sensing and selectivity of the two MOFs can be ascribed to the network interpenetration that, shaping the void, creates monodimensional channels, decorated by exposed oxygen atom sites selective for arsenate sensing in TMU-67 and isolated cavities, covered by phenyl groups selective for fluoride recognition in TMU-68.

Osteopontin (OPN), a novel hepatic damage marker, as well as several non-coding RNA seem to be associated with liver aging, a little studied and not yet defined process. The aim of the study was to evaluate the expression variations of OPN and miRNA-181a, the transcriptional profiling of long non coding (lnc) RNA GAS-5/miRNA-222 axis and lncRNA NEAT-1 in liver tissue of rats. In addition, to monitor the senescence process, the telomere shortening and TERT/TERC gene expression were also measured. Three groups of male Wistar rats were studied: A (n = 6, young); B (n = 13, adult); C (n = 10, old). Total RNA, including miRNAs, was extracted from liver and analysed by Real-Time PCR. Ultrasound and biochemical evaluation were performed in all rats as well as the histological analysis. OPN mRNA resulted lower in C with respect to A and B while miRNA-181a expression was significantly increased as a function of age. An increasing of both NEAT-1 and miRNA-222 expression as a function of age in parallel with a decreasing of GAS-5 expression in young and old rats, but not in the adults, was observed. A positive correlation was detected between miRNA-181a and miRNA-222. The hepatic ultrasound analysis revealed areas of hyperechogenicity distributed as a function of age. A significant telomere shortening was measured as a function of age while the two subunits TERT and TERC expressions showed an opposite trend. This work could provide a valid starting point to better understand the physiopathological changes during aging, pinpointing in the OPN/miRNA-181a axis significant predictors of successful aging.

[Re3(μ-H)3(μ3-CH3)(CO)9]- (1) reacts with CO at 273 K to quantitatively give the [Re3(μ-H)3(μ-CH3)(CO)10]- derivative (2) through the conversion of the methyl group from triply to doubly-bridging coordination. An NMR isotopic perturbation experiment demonstrates the unsymmetrical bridging of the methyl group on the Re-Re bond, and a fast exchange, in solution, between one agostic and two terminal C H bonds. This is in agreement with X-Ray diffraction analysis performed on single crystals of 2. In solution at room temperature 2 decomposes with CH4 elimination, which is also observed when 2 is treated with CO affording the [Re3(μ-H)2(CO)12]- anion. The opening of the triple bridging methyl coordination in 1 occurs also with other different L ligands, yielding to the syn and anti isomers of unsymmetrically bridged methyl complexes of general formula [Re3(μ-H)3(μ-CH3)(CO)9(L)]- (L = MeCN, PMePh2, THF). The kinetic and thermodynamic stabilities of these isomers vary with the nucleophilicity of the ligand and the polarity of the solvent. In particular, the strong nucleophile PMePh2 affords the quantitative conversion of anion 1 into the thermodynamic syn isomer, which is stable in THF at room temperature for several days. On the contrary, weak nucleophiles, such as MeCN or THF, give equilibrium mixtures containing residual amounts of anion 1. The adducts with MeCN are stable in solution at room temperature for several hours, while decompose fastly in neat MeCN affording mainly the cluster anion [Re3(μ-H)4(CO)9(MeCN)]-. This suggests that cluster stabilization after methane evolution follows a different path with respect to that observed in the reaction of 1 with CO.

Three cationic nonporous copper(I) coordination polymers containing bis-pyrazolyl flexible ligands have been prepared and characterized, namely, {[Cu(μ-bdb)1.5](PF6)}n (1), {[Cu(μ-bpb)2](PF6)}n (2)...

A bis-pyridyl-bis-amide ligand containing a biphenylene scaffold was combined with four different dicarboxylic acids in the presence of Zn(NO3)2·6H2O under solvothermal conditions, using DMF as solvent. The corresponding coordination frameworks were structurally characterized by single crystal diffraction analysis, the topological and thermal analysis were also conducted. The removing of the included DMF was investigated through solvent assisted activation protocol, the final outcomes being determined by 1HNMR analysis. The dimensionality of the solid networks depends on the type of dicarboxylic acid employed. The use of isophthalic acid and 5-amino-isophthalic acid led to the isolation of 2D-frameworks (PUM20 and PUM32, topological type 3,5L2), while a 1-D polymer was obtained using 2-methoxy-isophthalic acid (PUM30, of topological type SP 1-periodic, ladder-like). Finally, the use of terephthalic acid led to a pillared 2-fold interpenetrated 3D-structure (PUM198, of topological type fet).

Two new fluorinated metal–organic frameworks [Zn2(hfipbb)2(4-bpdh)]·0.5DMF (TMU-55) and [Zn2(hfipbb)2(4-bpdb)]·2DMF (HTMU-55) have been solvothermally synthesized by the reaction of two linear N-containing ligands as pillars (4-bpdb = 1,4-bis(4-pyridyl)-2,3-diaza-1,3-butadiene and 4-bpdh = 2,5-bis(4-pyridyl)-3,4-diaza-2,4-hexadiene), and a flexible V-shaped fluorinated linker, H2hfipbb = 4,4′-(hexafluoroisopropylidene) bis(benzoic acid). The two compounds were characterized by different techniques such as X-ray crystallography, powder X-ray diffraction (PXRD), infrared spectroscopy (IR), contact angle (CA), thermogravimetry (TGA), field emission scanning electron microscopy (FE-SEM), inductively coupled plasma (ICP), and Brunauer–Emmett–Teller (BET) surface area analysis. Both compounds are structurally similar and exhibit three dimensional (3D) coordination frameworks with hydrophobic properties. The catalytic activity of these isoreticular F-MOFs as efficient base heterogeneous catalysts toward the Knoevenagel condensation reaction was tested and compared to each other. TMU-55 and HTMU-55 exhibited good catalytic activity (with a minimum amount of catalyst, 2.5 mg (0.5 mol%), and the shortest time, 5 min) in water as a green solvent with excellent conversions. Also, the results were considerably higher in comparison with most of the values given in the literature for this reaction at ambient temperature. The remarkable catalytic performance of TMU-55 and HTMU-55 in water can be attributed to the presence of hydrophobic fluoro groups near the basic reaction center in the F-MOFs. These catalysts maintain their crystalline frameworks after the reaction and are easily recovered and reused at least for three cycles without significant loss in their catalytic activity. Furthermore, the conversion of benzaldehyde can be kept over 95% while the selectivity of the Knoevenagel reaction is kept at 100%.

The performance of solid luminogens depends on both their inherent electronic properties and their packing status. Intermolecular interactions have been exploited to achieve persistent room-temperature phosphorescence (RTP) from organic molecules. However, the design of organic materials with bright RTP and the rationalization of the role of interchromophoric electronic coupling remain challenging tasks. Cyclic triimidazole has been shown to be a promising scaffold for such purposes owing to its crystallization-induced room-temperature ultralong phosphorescence (RTUP), which has been associated with H-aggregation. Herein, we report three triimidazole derivatives as significant examples of multifaceted emission. In particular, dual fluorescence, RTUP, and phosphorescence from the molecular and supramolecular units were observed. H-aggregation is responsible for the red RTUP, and Br substituents favor yellow molecular phosphorescence while halogen-bonded Br???Br tetrameric units are involved in the blue-green phosphorescence.

Three new cationic silver(I) coordination polymers, {[Ag(μ-bpmb)](SO3CF3)}n (1), {[Ag(μ-bdb)1.5](SO3CF3)}n (2) and {[Ag(μ-bpb)2](NO3)}n (3), with flexible 1,4-bis[(pyrazolyl)methyl]benzene (bpmb), 1,4-bis[(3,5-dimethylpyrazolyl)methyl]benzene (bdb), and 1,4-bis(pyrazolyl)butane (bpb) have been prepared at room temperature by the solvent layering method. The three compounds were characterized by FT-IR spectroscopy, PXRD, elemental analyses and single-crystal X-ray diffraction. Compound 1 is a highly undulated polymeric 1D chain in which the silver ions adopt a linear geometry, coordinating two bpmb linkers. Compounds 2 and 3 are both 2D coordination polymers with their silver atoms being three and four coordinated, and resulting in 63-hcb and 44-sql underlying net topologies, respectively. The flexible bispyrazolyl ligands display various conformations in the solid state, causing the formation of different Ag…Ag separations in the polymeric structures.

Urea groups are known to form strong hydrogen bonds with molecules containing atom(s) that can act as hydrogen bond acceptor(s). Thus, urea is a particularly interesting building block for designing receptors for neutral or charged guests. In the quest for new sensors with enhanced performance for the detection of nitro-substituted compounds, two pillared metal-organic frameworks containing urea functional groups were synthesized and structurally characterized. The sensing properties of these frameworks toward nitro-analytes were investigated and compared to each other. The study clearly reveals the importance of urea groups orientation inside the pore cavity of MOFs, as well as the supramolecular interactions between the interpenetrated networks. This work is interesting as it represents the first example of urea-functionalized MOFs for nitro-analytes recognition.

A novel Ni-based 2,2′-bisdipyrrinato complex bearing peripheral benzoic acid groups (Ni-bisdpmCOOH) has been synthesized and characterized. Electrochemical investigations revealed a high energy LUMO level that, combined with its absorption properties extending up to the NIR region, is compatible with its use as a sensitizer in thermodynamically uphill photocatalytic reactions, such as proton and carbon dioxide photoreduction. A sensitized photo-anode was prepared by adsorbing Ni-bisdpmCOOH onto a TiO2 film, which showed an incident photon to current efficiency, measured at 0.62 V vs. RHE, extending up to the visible light region. This demonstrates that electronically excited Ni-bisdpmCOOH is effectively able to inject electrons into the conduction band of TiO2, thus opening the way for effective TiO2 sensitization or MOF implementation of the molecule itself for energetic applications.

Four new non-porous CuI-coordination polymers [Cu2(μ3-I)2(μ-bpb)]n (1a), [Cu(μ2-I)(μ-bpb)]n (1b), [Cu4(μ2-I)4(μ-bpmb)4]n (2), and [CuI(μ-bdb)]n (3) (bpb = 1,4-bis(pyrazolyl)butane; bpmb = 1,4-bis[(pyrazolyl)methyl]benzene; bdb = 1,4-bis[(3,5-dimethylpyrazolyl)methyl]benzene) have been successfully prepared and their structures fully characterized by single-crystal X-ray diffraction, FT-IR spectroscopy, PXRD and elemental analysis. Crystallographic investigation revealed that 1a, 1b, and 2 exhibit two-dimensional (2D) structures; in 1a parallel [Cu2I2]n staircase motifs are cross-linked into two-dimensional sheets by bpb linkers with a fully extended conformation, while in the structures of 1b and 2 Cu2I2 rhomboid dimers are linked by bpb and pbmb ligands, respectively, into two-dimensional sheets with a 44-sql net. Differently, compound 3 shows a one-dimensional (1D) zigzag chain structure with monomeric CuI units. All the four non-porous coordination polymers show the ability to capture volatile iodine in the gas phase. The solid-state photoluminescence properties of 1a, 1b, and 2 have also been investigated. The iodine-adsorbed samples 1a-I2, 1b-I2, and 2-I2 show no fluorescence behavior.

Stepwise self-assembly processes using new lanthanide metalloligands (Ln-MLs) and silver salts have been successfully applied to isolate 4f-4d heterometallic coordination networks of four different structural types. In particular, the new lanthanide tetrakis-chelate complexes NEt4[Ln(L1)4] [HL1 = 1,3-bis(4'-cyanophenyl)-1,3-propanedione; Ln = Eu (1a), La (1b), Nd (1c), Tb (1d)] and NEt4[Ln(L2)4] (HL2 = 1,3-bis(4'-pyridyl)-1,3-propanedione; Ln = Eu (1e), Nd (1f)] have been synthesized, characterized, and reacted with different silver salts. The use of NEt4[Ln-(L1)4] allowed then to isolate and characterize i) neutral onedimensional ladder-like species of formula [Ln(L1)4Ag] [Ln = Eu (2a), La(2b), Nd(2c), Tb(2d)] and ii) their supramolecular isomers [Ln(L1)4Ag] [Ln = Eu (3a), La (3b), Nd (3c), Tb (3d)] showing a very unstable 2D network structure, iii) the cationic 2D species [Ln(L1)4Ag2]X [Ln = Eu, X = PF6-, CF3SO3-, ClO4- (4a-4c); Ln = Tb, Nd, La X = PF6 - (4d-4f)], and, only for lanthanum, iv) a fourth 2D species of formula [La(L1)4(H2O)Ag] (5) and SQL topology. Of the eight nitrile groups on the MLs potentially coordinating, only a partial number is used for networking with Ag(I), that is, only two in families 2 and 3 and four in family 4 and in network 5. Finally, the four structural types are rationalized in terms of a new "pincer-like" secondary building unit (SBU) consisting of a silver cation coordinating two central carbon atoms (γ carbon) of two different diketonate ligands on the same ML. Therefore, it is shown that compounds 5, 4, and 2-3 contain, respectively, none, one, or two of such pincer-like SBUs. The luminescence properties of the Ln-MLs and some of their polymeric species have been also investigated in solution and in the solid state.

Dilated cardiomyopathy (DCM) is a myocardial disease of dogs and humans characterized by progressive ventricular dilation and depressed contractility and it is a frequent cause of heart failure. Conventional pharmacological therapy cannot reverse the progression of the disease and, in humans, cardiac transplantation remains the only option during the final stages of heart failure. Cytoprotective gene therapy with vascular endothelial growth factor-B167 (VEGF-B167) has proved an effective alternative therapy, halting the progression of the disease in experimental studies on dogs. The aim of this work was to test the tolerability and feasibility of intracoronary administration, under fluoroscopic guidance, of VEGF-B167 carried by adeno-associated viral vectors in canine DCM patients. Ten patients underwent the gene delivery procedure. The intraoperative phase was well tolerated by all dogs. Clinical and echocardiographic assessments at 7- and 30-days post-procedure showed stable conditions compared to the pre-procedure phase. The results of this work indicate that intracoronary VEGF-B167 gene delivery is feasible and tolerated in dogs with DCM. Further monitoring/investigations are ongoing to evaluate the effects of this therapy on disease progression.

Prompt coronary catheterization and revascularization have dramatically improved the outcome of myocardial infarction, but also have resulted in a growing number of survived patients with permanent structural damage of the heart, which frequently leads to heart failure. Finding new treatments for this condition is a largely unmet clinical need 1, especially because of the incapacity of cardiomyocytes to replicate after birth and thus achieve regeneration of the lost contractile tissue 2. Here we show that expression of human microRNA-199a in infarcted pig hearts is capable of stimulating cardiac repair. One month after myocardial infarction and delivery of this microRNA through an adeno-associated viral vector, the treated animals showed marked improvements in both global and regional contractility, increased muscle mass and reduced scar size. These functional and morphological findings correlated with cardiomyocyte de-differentiation and proliferation. At longer follow-up, however, persistent and uncontrolled expression of the microRNA resulted in sudden arrhythmic death of most of the treated pigs. Such events were concurrent with myocardial infiltration of proliferating cells displaying a poorly differentiated myoblastic phenotype. These results show that achieving cardiac repair through the stimulation of endogenous cardiomyocyte proliferation is attainable in large mammals, however this therapy needs to be tightly dosed.

Cyclic triimidazole (C9H6N6, L), with C3h molecular symmetry and three nitrogen atoms available for coordination, is here successfully employed for the first time in the synthesis of coordination compounds. In particular, by varying the reaction conditions (e.g., solvent, temperature, template), seven Cu(I)-halide coordinat on polymers of different dimensionality are obtained: two 1D polymers, [CuIL]n (1) and {[CuIL]·(I2)0.5}n (2), three 2D nets, [CuXL]n (X = I, Br) (3-5), and two 3D networks, [CuClL]n (6) and {[Cu3L4]I3}n (7). Single crystal X-ray diffraction analysis reveals that the structural versatility of both the ligand and the CuX moiety allows isolating 1D double-stranded stairs in which L is monodentate, 2D layers containing either Cu2(?-X)2 or Cu2(?-X) moieties and bidentate L ligands, 3D frameworks built up by tridentate L linkers and either monodentate or noncoordinating halogen atoms. The 3D frameworks show nets of srs and bor topologies. The SHG efficiency of powders of 7 (the only noncentrosymmetric derivative of the series) is 10 times higher than that of sucrose. Phosphorescent emission of XLCT character is observed for 1 and 6.

Dilated cardiomyopathy (DCM) is a myocardial disease of dogs and humans characterized by progressive ventricular dilation and depressed contractility and it is a frequent cause of heart failure. Conventional pharmacological therapy cannot reverse the progression of the disease and, in humans, cardiac transplantation remains the only option during the final stages of heart failure. Cytoprotective gene therapy with vascular endothelial growth factor-B167 (VEGF-B167) has proved an effective alternative therapy, halting the progression of the disease in experimental studies on dogs. The aim of this work was to test the tolerability and feasibility of intracoronary administration, under fluoroscopic guidance, of VEGF-B167 carried by adeno-associated viral vectors in canine DCM patients. Ten patients underwent the gene delivery procedure. The intraoperative phase was well tolerated by all dogs. Clinical and echocardiographic assessments at 7- and 30-days post-procedure showed stable conditions compared to the pre-procedure phase. The results of this work indicate that intracoronary VEGF-B167 gene delivery is feasible and tolerated in dogs with DCM. Further monitoring/investigations are ongoing to evaluate the effects of this therapy on disease progression.

A new two-dimensional zinc(II) coordination polymer of 5-aminoisophtalic acid (H2AIP), namely [Zn(AIP)(DMSO)]n (Zn-CP), has been successfully prepared via conventional heating at 100 ​°C in a (2:1) dimethyl sulfoxide/ethanol solvent mixture. The compound has been characterized by FT-IR spectroscopy, elemental and thermogravimetric analyses, powder and single-crystal X-ray diffraction techniques. Crystal structure of Zn-CP shows the presence of neutral layers of composition Zn(AIP) and 63-hcb topology, which are decorated only on one side with dangling DMSO molecules. Moreover, the composite Zn-CP@Foam has also been fabricated growing Zn-CP crystals on the 3D porous structure of a melamine-formaldehyde foam (MF) by immersion of pieces of MF in the precursor solution of the coordination polymer. Both Zn-CP and Zn-CP@Foam materials have been studied for the adsorption in water of cationic dyes, such as Crystal Violet (CV), Victoria Blue (VB) and Malachite Green (MG), and anionic dyes, such as Sunset Yellow (SY), Congo Red (CR) and Aniline Blue (AB). Results show selective sorption of cationic dyes only, with faster and larger adsorption capacity observed for the porous composite material which has an adsorption capacity for Victoria Blue (VB) (102 ​mg ​g−1) more than twice larger than that found for pristine Zn-CP powder (48 ​mg ​g−1). This selectivity towards cationic dyes is attributed to electrostatic interactions between the cationic dye molecules and the negatively charged surface of the zinc coordination polymer, which shows a zeta potential of −13.7 ​mV. Moreover, dye adsorbed Zn-CP and Zn-CP@Foam can be regenerated by immersion in a water/acetic acid solution (1:1) and reused with almost the same efficiency.

A new neutral cadmium-organic framework with a pillared layer structure, [Cd3(BTC)2(4-bpdb)2] (H3BTC = benzene-1,3,5-tricarboxylic acid; 4-bpdb = 1,4-bis(4-pyridyl)-2,3-diaza-1,3-butadiene), has been synthesized via solvothermal reaction of cadmium nitrate with the tricarboxylic acid H3BTC and the linear bispyridyl linker 4-bpdb. The complex has been characterized by single crystal X-ray diffraction, showing to possess a 3D porous network of jcr7 topology. The capability of the prepared MOF in adsorbing the organic dyes Congo Red (CR) and Neutral Red (NR), together with kinetics and thermodynamics of their adsorption, have been investigated in detail. The adsorption process was well described by pseudo-first order and pseudo-second order kinetics for CR and NR, respectively. In addition, conversion of the MOF 3D architecture into nano-sized cadmium oxide particles has also been studied.

Chronological age is considered one of the major risk factors for cardiovascular disease and mortality. The study aimed to evaluate the transcriptional levels of the natriuretic peptides (NP), endothelin (ET)-1, adrenomedullin (ADM), their receptors and long non-coding (Lnc) RNA MIAT, MALAT-1, CARMEN and XIST in rat cardiac tissue as cardiovascular biomarkers of aging. Three groups of male Wistar rats were studied: A (n = 6; young), B (n = 13; adult), C (n = 10; old). Total RNA was extracted from left ventricle and analyzed by Real-Time PCR. Echocardiographic and histological analyses were performed. A significant increase of Atrial NP (ANP) and Brain NP (BNP) mRNA was observed in C while C-type NP (CNP) remained in a steady-state in B and C; ET-1 mRNA increased significantly as a function of age. Any difference was observed for NP receptors. ET A expression was statistically lower in B than A while ET B were similar in all the three groups. The ADM showed an opposite trend to that of the other peptides decreasing significantly as a function of age and presenting a counter-regulation of calcitonin receptor-like receptor (CLR) and receptor activity modifying protein (RAMP)-2. LncRNA transcripts decreased significantly as a function of age except for XIST. ADM and LncRNA trend suggest that the animals are subjected to “successful aging” as also confirmed by histological analysis. Applying a multivariate logistic regression analysis, only LnANP (p = 0.003) and LnADM (p = 0.023) resulted significantly associated with aging identifying them, for the first time, as independent markers of aging. The study underlining the importance of a multi-label biomolecular approach in the evaluation of aging.

The understanding of the mechanisms involved in crystal packing effects on the photophysical properties of a molecular entity is fundamental to engineer solid materials for specific applications. In fact, besides rigidification and protection from oxygen quenching, crystal packing influences the emissive properties through specific interactions. In the present work, by a critical comparison among the mono- (1Br), di- (2Br) and tri-bromo (3Br) derivatives of triimidazo[1,2-a:1',2'-c:1",2''-e][1,3,5]triazine, the role of their structural features on the multifaceted emission, spanning from dual fluorescence to ultralong phosphorescence, is elucidated. In particular, conformational distortions are found to be responsible for dual fluorescence, halogen-bonding interactions are at the origin of the long-lived phosphorescence and pi-pi interactions resulting in the formation of columnar or dimeric H-aggregates induce room- temperature ultralong phosphorescence.

Two new diorganotin(IV) complexes, Me2SnL and Ph2SnL, have been synthesized from the reaction of Me2SnCl2 and Ph2SnCl2 with the hydrazone H2L [H2L = (Furan-2-yl) (5-hydroxy-3-methyl-5-phenyl-4,5-dihydro-1H-pyrazol-1-yl)-methanone] derived from furan-2-carbohydrazide and benzoylacetone. The new compounds have been characterized by elemental and spectroscopic analyses. The crystal structures of the monohydrate form of the ligand and of the Me2SnL derivative have been also determined by X-ray crystallography. Experimental evidences confirm the existence of the hydrazone ligand exclusively in cyclic form in both solution and solid state. On coordination to tin the hydrazone undergoes a ring opening reaction and a doubly deprotonation to act as a tridentate ligand via imine nitrogen and enolic oxygens. The tin atom in the complexes is five coordinate with geometry between square-pyramidal and trigonal-bipyramidal. The in vitro antibacterial activity of ligand and its complexes has been evaluated against Gram-positive (Bacillus subtilis and Staphylococcus aureus) and Gram-negative (Escherichia coli and Pseudomonas aeruginosa) bacteria. The interaction between compounds with bacterial DNA was also studied by molecular docking. Our findings indicate that diphenyltin(IV) complex, by binding to DNA via minor groove to TATA sequence in genes upstream, has good activities along with the standard antibacterial drugs. Our agarose-gel electrophoresis experiments show that the ligand exert DNA cleavage, while Me2SnL and Ph2SnL did not.

A theoretical investigation of bond lengths and bond energies for several kinds of halogen bonding interactions is carried out using the PIXEL method. The effect of different kinds of activating agents, fluoro-, nitro-, ethynyl substitution and combinations thereof, is assessed quantitatively, and is found to be fully consistent with the results of literature screenings of the corresponding strengths, as judged by the ease of formation of cocrystals. In the best combination of activators the halogen bond is comparable or superior to a strong O–H⋯O hydrogen bond in what concerns stabilization energies and stretching force constants. At least with iodine acceptors, in our picture the halogen-bonding effect is a localized interaction arising from the detail of the electron distribution at the halogen atom, mainly of a Coulombic-polarization nature but with dispersion energies contributing significantly. Binding energies correlate with the electrostatic potential at the tip of the halogen and even with Mulliken population analysis atomic charges, providing easily accessible guidelines for crystal engineers. For one typical cocrystal structure the analysis of separate molecule–molecule energies reveals the nature of the packing forces and rank halogen bonding as the main influence, closely followed by coplanar stacking of coformers.

Solid-state luminescent materials with long lifetimes are the subject of ever-growing interest from both a scientific and a technological point of view. However, when dealing with organic compounds, the achievement of highly efficient materials is limited by aggregation-caused quenching (ACQ) phenomena on one side and by ultrafast deactivation of the excited states on the other. Here, we report on a simple organic molecule, namely, cyclic triimidazole (C9H6N6), 1, showing crystallization-induced emissive (CIE) behavior and, in particular, ultralong phosphorescence due to strong coupling in H-aggregated molecules. Our experimental data reveal that luminescence lifetimes up to 1 s, which are several orders of magnitude longer than those of conventional organic fluorophores, can be realized under ambient conditions, thus expanding the class of organic materials for phosphorescence applications.