Organometallic Compounds

The dinuclear gold(I) dithiophosphonate complex, [Au 2 (dtp) 2 ] (1), where dtp ) [S 2 P(R)(OR′)] -with R ) p-C 6 H 4 -OCH 3 ; R′) c-C 5 H 9 , has been synthesized and its reaction studied with the phosphine ligands PPh 3 and Ph 2 P(CH 2 ) n -PPh 2 (n ) 1-4). Compound 1 contains two gold atoms homobridged by the anionic dithiophosphonate ligand, forming an eight-membered ring complex in a chair form. After the reaction of 1 with diphosphine ligands, the dinuclear open-ring complexes Au 2 (dppm)(dtp) 2 (2), Au 2 (dppe)(dtp) 2 (3), Au 2 (dppp)(dtp) 2 (4), Au 2 (dppb)(dtp) 2 (5) were formed (dppm ) diphenylphosphinomethane; dppe ) diphenylphosphinoethane; dppp ) diphenylphosphinopropane; dppb ) diphenylphosphinobutane). The reaction with dppm is stoichiometry-dependent. Thus, when 1 reacts with 2 equiv of dppm, the ionic complex [Au 2 (dppm) 2 (dtp)]dtp forms. This dtp counterion was exchanged with tetrafluoroborate to yield [Au 2 (dppm) 2 (dtp)]BF 4 , the crystallization of which afforded two interconvertible isomers, 6-yellow and 7-white. Reaction of 1 with PPh 3 affords the tetracoordinate mononuclear complex [Au(dtp)(PPh 3 ) 2 ] (8). The molecular structures of 1-8 were confirmed by X-ray crystallography and show multiple coordination modes and geometries. The crystal structures of 1 and its reaction products with dppm (2, 6, 7) show short intramolecular Au‚‚‚Au aurophilic bonding interactions of 2.95-3.10 Å while no intermolecular interactions were discernible. However, reaction products of 1 with longer-chain Ph 2 P(CH 2 ) n PPh 2 ligands, n ) 2-4, exhibit structures that lack both intra-and intermolecular Au‚‚‚Au interactions.

Punicalagin (PU) is a known antioxidant. The present study examined PU to protect against lead-induced oxidative stress (OS) testicular damage in mice. Significant increase in lipid peroxidation (LPO) after intraperitoneal injection of lead acetate (LA) indicated enormous generation of reactive oxygen species (ROS). Lead-induced OS has a direct effect on the differentiation of spermatogonial cells, showing a significant decline in sperm count. Supplementation of PU significantly changes values of LPO and glutathione (GSH) with a concomitant increase in sperm count, a marked decrease in the abnormal sperms, and a decline in the morphologically abnormal sperm population. Moreover, the histopathological evaluation of testes and epididymides showed severe changes in mice treated with LA. PU significantly induced nuclear factor erythroid-2 related factor 2-like 2 (Nrf2) expression and phase II enzymes, and data suggest that PU may inhibit OS through Nrf2 activation. The fertility test proved that PU might play an important role in male infertility treatment, especially in the type of infertility induced by OS.

Somatostatin receptor PET tracers such as [ 68 Ga-DOTA, 1-Nal 3 ]-octreotide ( 68 Ga-DOTANOC) and [ 68 Ga-DOTA,Tyr 3 ]octreotate ( 68 Ga-DOTATATE) have shown promising results in patients with neuroendocrine tumors, with a higher lesion detection rate than is achieved with 18 F-fluorodihydroxyphenyl-Lalanine PET, somatostatin receptor SPECT, CT, or MR imaging. 68 Ga-DOTANOC has high affinity for somatostatin receptor subtypes 2, 3, and 5 (sst 2,3,5 ). It has a wider receptor binding profile than 68 Ga-DOTATATE, which is sst 2 -selective. The wider receptor binding profile might be advantageous for imaging because neuroendocrine tumors express different subtypes of somatostatin receptors. The goal of this study was to prospectively compare 68 Ga-DOTANOC and 68 Ga-DOTATATE PET/CT in the same patients with gastroenteropancreatic neuroendocrine tumors (GEP-NETs) and to evaluate the clinical impact of 68 Ga-DOTANOC PET/CT. Methods: Eighteen patients with biopsy-proven GEP-NETs were evaluated with 68 Ga-DOTANOC and 68 Ga-DOTATATE using a randomized crossover design. Labeling of DOTANOC and DOTATATE with 68 Ga was standardized using a fully automated synthesis device. PET/CT findings were compared with 3-phase CT scans and in some patients with MR imaging, 18 F-FDG PET/CT, and histology. Uptake in organs and tumor lesions was quantified and compared by calculation of maximum standardized uptake values (SUVmax) using volume computer-assisted reading. Results: Histology revealed low-grade GEP-NETs (G1) in 4 patients, intermediate grade (G2) in 7, and high grade (G3) in 7. 68 Ga-DOTANOC and 68 Ga-DOTATATE were false-negative in only 1 of 18 patients. In total, 248 lesions were confirmed by crosssectional and PET imaging. The lesion-based sensitivity of 68 Ga-DOTANOC PET was 93.5%, compared with 85.5% for 68 Ga-DOTATATE PET (P 5 0.005). The better performance of 68 Ga-DOTANOC PET is attributed mainly to the significantly higher detection rate of liver metastases rather than tumor differentiation grade. Multivariate analysis revealed significantly higher SUVmax in G1 tumors than in G3 tumors (P 5 0.009). This finding was less pronounced with 68 Ga-DOTANOC (P . 0.001). Altogether, 68 Ga-DOTANOC changed treatment in 3 of 18 patients (17%). Conclusion: The sst 2,3,5 -specific radiotracer 68 Ga-DOTANOC detected significantly more lesions than the sst 2 -specific radiotracer 68 Ga-DOTATATE in our patients with GEP-NETs. The clinical relevance of this finding has to be proven in larger studies.

Earlier studies have shown that modification of the octapeptide octreotide in positions 3 and 8 may result in compounds with increased somatostatin receptor affinity that, if radiolabelled, display improved uptake in somatostatin receptor-positive tumours. The aim of a recent research study in our laboratory was to employ the parallel peptide synthesis approach by further exchanging the amino acid in position 3 of octreotide and coupling the macrocyclic chelator DOTA(1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid) to these peptides for labelling with radiometals like gallium-67 or -68, indium-111, yttrium-90 and lutetium-177. The purpose was to find radiopeptides with an improved somatostatin receptor binding profile in order to extend the spectrum of targeted tumours. A first peptide, [ 111 In, 90 Y-DOTA]-1-Nal 3 -octreotide ( In, 90 Y-DOTA-NOC), was isolated which showed an improved profile. In III -DOTA-NOC exhibited the following IC 50 values (nM) when studied in competition with [ 125 I][Leu 8 , D-Trp 22 , Tyr 25 ]somatostatin-28 (values for Y III -DOTA-NOC are shown in parentheses): sstr2, 2.9±0.1 (3.3±0.2); sstr3, 8±2 (26±1.9); sstr5, 11.2±3.5 (10.4±1.6). Affinity towards sstr1 and 4 was very low or absent. In III -DOTA-NOC is superior to all somatostatinbased radiopeptides having this particular type of binding profile, including DOTA-lanreotide, and has three to four times higher binding affinity to sstr2 than In III ,Y III -DOTA-Tyr 3 -octreotide (In III ,Y III -DOTA-TOC). In addition, [ 111 In]DOTA-NOC showed a specific and high rate of internalization into AR4-2J rat pancreatic tumour cells which, after 4 h, was about two times higher than that of [ 111 In]DOTA-TOC and three times higher than that of [ 111 In]DOTA-octreotide ([ 111 In]DOTA-OC). The internalized radiopeptides were externalized intact upon 2 h of internalization followed by an acid wash. After 2-3 h of externalization a plateau is reached, indicating a steadystate situation explained by reactivation of the receptors followed by re-endocytosis. Biodistribution studies in CA 20948 tumour-bearing rats showed rapid clearance from all sstr-negative tissues except the kidneys. At 4 h the uptake of [ 111 In]DOTA-NOC in the tumour and sstr-positive tissues, such as adrenals, stomach and pancreas, was three to four times higher than that of [ 111 In]DOTA-TOC. Differential blocking studies indicate that this is at least partially due to the uptake mediated by sstr3 and sstr5. These very promising preclinical data justify the use of this new radiopeptide for imaging and potentially internal radiotherapy studies in patients.

• Neuroinflammatory markers and microglia were compared in young mice with and without early chronic Pb exposure. • Mice with Pb levels from 2.66 to 20.31 g/dL had dose-dependent reduction of cytokine IL6. • Mice with Pb levels from 2.66 to 20.31 g/dL had dose-dependent reduction of detectable microglia. • No evidence of increased neuroinflammation was found.

For treating Leishmania major infection in BALB/c mice, we used thalidomide in conjunction with glucantime. Groups of mice were challenged with 5 × 10 3 metacyclic promastigotes of L. major subcutaneously. A week after the challenge, drug treatment was started and continued for 12 days. Thalidomide was orally administrated 30 mg/kg/day and glucantime was administrated intraperitoneally (200 mg/kg/day). It was shown that the combined therapy is more effective than single therapies with each one of the drugs since the foot pad swelling in the group of mice received thalidomide and glucantime was significantly decreased (0.9 ± 0.2 mm) compared to mice treated with either glucantime, thalidomide, or carrier alone (1.2 ± 0.25, 1.4 ± 0.3, and 1.7 ± 0.27 mm, respectively). Cytokine study showed that the effect of thalidomide was not dependent on IL-12; however, it up-regulated IFN-γ and down-regulated IL-10 production. Conclusively, thalidomide seems promising as a conjunctive therapy with antimony in murine model of visceral leishmaniasis.

Searching for new prospective antitrypanosomal agents, three novel Ru(II)cyclopentadienyl compounds, [Ru( 5 -C 5 H 5 )(PPh 3 )L], with HL = bioactive 5-nitrofuryl containing thiosemicarbazones were synthesized and characterized in the solid state and in solution. The compounds were evaluated in vitro on the blood circulating trypomastigote form of Trypanosoma cruzi (Dm28c strain), the infective form of T. brucei brucei (strain 427) and on J774 murine macrophages and human-derived EA.hy926 endothelial cells. The compounds were active against both parasites with IC 50 values in the micromolar range. Interestingly, they are much more active on T. cruzi than previously developed Ru(II) classical and organometallic compounds with the same bioactive ligands. The new compounds showed moderate to very good selectivity towards the parasites in respect to mammalian cells. The global results point at [RuCp(PPh 3 )L2] (L2 = N-methyl derivative of 5-nitrofuryl containing thiosemicarbazone and Cp = cyclopentadienyl) as the most promising compound for further developments (IC 50 T. cruzi = 0.41 µM; IC 50 T. brucei brucei = 3.5 µM). Moreover, this compound shows excellent selectivity towards T. cruzi (SI >49) and good selectivity towards T. brucei brucei (SI >6). In order to get insight into the mechanism of antiparasitic action, the intracellular free radical production capacity of the new compounds was assessed by ESR. DMPO (5,5-dimethyl-1-pirroline-N-oxide) spin adducts related to the bioreduction of the complexes and to redox cycling processes were characterized. In addition, DNA competitive binding studies with ethidium bromide by fluorescence measurements showed that the compounds interact with this biomolecule.

Searching for prospective metal-based drugs for the treatment of Chagas disease, a new series of ten mixed-ligand oxidovanadium(IV) complexes, [V IV O(L-2H)(NN)], where L is a tridentate salicylaldehyde semicarbazone derivative (L1-L5) and NN is either 5-amine-1,10-phenanthroline (aminophen) or 5,6epoxy-5,6-dihydro-1,10-phenanthroline (epoxyphen), were synthesized. The compounds were characterized in the solid state and in solution. EPR spectroscopy suggests that the NN ligands act as bidentate through both nitrogen donor atoms in an axial-equatorial mode. The stability of the complexes in solution was investigated by EPR and 51 V-nuclear magnetic resonance spectroscopies. The complexes were evaluated in vitro for their activities against Trypanosoma cruzi (T. cruzi), the parasite responsible for the disease, and their selectivity was analyzed using J-774 murine macrophages, as a mammalian model. All the complexes are more active than both the reference drug Nifurtimox and the previously reported [V IV O(L-2H)(NN)] complexes. In general they are more active than the corresponding free NN ligands. Complexation led to highly increased selectivities towards the parasite. In addition, the lipophilicity of the compounds was determined and correlated with the observed activity in order to perform a QSAR (quantitative structure-activity relationship) study. A clear quadratic correlation is found. This study also confirms the influence of the structure of the co-ligand on the anti-T. cruzi effect. To get insight into the mechanism of action of the compounds, the changes in biochemical pathways promoted by two of the most active and most selective complexes are studied by analyzing a few of the parasite excreted metabolites by 1 H NMR spectroscopy. The combined information suggests that the mitochondrion could be a target for these complexes. Furthermore, DNA was preliminarily evaluated as a potential target by using atomic force microscopy (AFM), which showed that the complexes display an ability to interact with this biomolecule.

Background Hypercholesterolemia (HC) impairs acetylcholine-induced relaxation but has little effect on that caused by the NO donor sodium nitroprusside (SNP), suggesting that acetylcholine releases less NO from the endothelium in HC. The relaxation to authentic NO gas, however, is also impaired in HC aortic smooth muscle, indicating an abnormal smooth muscle response. NO relaxes arteries by both cGMP-dependent and -independent mechanisms, and the response involves calcium (Ca 2+ ) store refilling via the sarco/endoplasmic reticulum calcium ATPase (SERCA). We studied the involvement of cGMP and SERCA in the smooth muscle response to NO and SNP in HC rabbit aorta. Methods and Results A selective guanylyl cyclase inhibitor, 1H-[1,2,4]-oxadiazole-[4,3-a]quinoxalin-1-one, eliminated SNP-induced relaxation but only partially blocked NO-induced relaxation in both normal and HC aorta. The residual relaxation to NO was still less in HC and, in both normal and HC aorta, was abolished by conco...

In the present work, we succeeded in alternatively depositing inorganic nanoparticles and functionalized DNA bases onto the water/oil interface from the water and oil bulk phases. The ligands used were functional thymines and adenines. Their thiol and phosphate groups were used to cap inorganic nanoparticles and their thymine and adenine groups to alter the surface functionality of the nanoparticles, thus enabling a layer-by-layer growth fashion of nanoparticles at the interface. The multiple particle ligation rendered the resulting nanoparticle films rather mechanically robust. As results, the freestanding asymmetric bilayer and trilayer films, composed of negatively-charged Au, positively-charged CdTe, and/or organic Ag nanoparticles were constructed; their areas were as large as over several centimetres, depending on the sizes of the containers used. Our work should bring up a novel methodology to generate asymmetric multilayer films of nanoparticles with a defined control of electron or charge across the films.

The increasingly rapid development of metal organic frameworks (MOFs) or porous coordination polymers (PCPs) over the past two decades has attracted considerable attention from both academic and industrial researchers because they offer unprecedented levels of permanent porosity and exceptional opportunities for design of materials from the molecule up. 1aÀn,2aÀ2k Furthermore, their chemical and structural diversity offers the possibility of combining porosity with other important properties, such as magnetism, luminescence, semiconductivity, and catalytic activity. 1fÀh,m,pÀu The fact that MOFs are amenabled prior to design distinguishes them from most other classes of materials and is a consequence of the geometry of their chemical building blocks which manifests itself in the topology of the resulting crystal structures. 3aÀg "Design" implies a blueprint or some other formal description developed prior to and in fact directing synthesis of the crystal in mind. 2c,d In this communication, we outline an algorithm for generating such designs, and we present output from two demonstration programs based on this algorithm. To discuss these designs, we employ a formalism variously called (in various communities) an "embedded net" or an "embedded graph" or a "geometric graph" or a "Euclidean graph", among other things; to eliminate ambiguity, we will refer to an embedded net as a geometric structure in 3D-space consisting of the following: 33 • a set of points, which we call nodes (although they are often 34 called vertices); 35 • a set of line segments, which we call edges (although they are 36 often called linkers), each with two nodes as end points. 37 If an embedded net is employed as a blueprint for a MOF, the 38 nodes would represent positions of atoms or molecular building 39 blocks (MBBs), positioned at specific points in 3D-space, while 40 the edges would represent bonds or molecular linkers between 41 atoms or MBBs, each linking the two end point nodes. 42 Such a geometric (as opposed to topological or combinatorial) 43 representation serves as a de facto blueprint for the design of 44 related MOFs because it tells us the shape of MBBs and the range 45 of their possible spatial arrangements; that is, just as a represen-46 tation is constructed from nodes linked by edges, a MOF can be 47 constructed from metals or MBBs linked by organic ligands. 48 We should distinguish the geometric notion of an embedded 49 net from two other extant notions: 50 • The combinatorial notion of a net (or a graph), consisting of 51 nodes and vertices and incidence relations between the two, 52 but with no spatial relations. Thus, two nets are combinato-53

We describe an experimental setup for reliable relative measurements of two-photon absorption spectra of organic molecules. The set-up utilizes tunable femtosecond laser system with optical parametric amplifier (OPA) and covers excitation wavelengths in the range 550-1600 nm. It utilizes two channels for simultaneous measurements of the unknown sample and the reference, such that all the pulse-to-pulse laser instabilities cancel out during measurements. Using the setup we measure absolute two-photon absorption (2PA) spectra of 4 commercial organic dyes (Rhodamine 640, Rhodamine 700, LDS-698 and LDS-798) with an estimated accuracy 15%. The data are corrected for the variations of the pulse duration and the beam profile with the excitation wavelength, and are applicable as secondary reference standards for 2PA measurements of the compounds with the emission wavelengths 600-800 nm.

Spectroscopic properties, two-photon absorption (TPA) and excited stated absorption (ESA), of two organic cyanine dyes and of a ruthenium based organometallic cyanine are compared in order to rationalize their similar ns-optical power limiting (OPL) efficiency in telecommunication wavelength range. The TPA contribution to the ns-OPL behavior is higher for both organic cyanines, while the main process is a TPA-induced ESA in the case of the organometallic system, in which the ruthenium induces a broadening of the NIR-ESA band and then a strong spectral overlap between TPA and ESA spectra.

Carbomagnesiation and carbozincation reactions are efficient and direct routes to prepare complex and stereodefined organomagnesium and organozinc reagents. However, carbon–carbon unsaturated bonds are generally unreactive toward organomagnesium and organozinc reagents. Thus, transition metals were employed to accomplish the carbometalation involving wide varieties of substrates and reagents. Recent advances of transition-metal-catalyzed carbomagnesiation and carbozincation reactions are reviewed in this article. The contents are separated into five sections: carbomagnesiation and carbozincation of (1) alkynes bearing an electron-withdrawing group; (2) alkynes bearing a directing group; (3) strained cyclopropenes; (4) unactivated alkynes or alkenes; and (5) substrates that have two carbon–carbon unsaturated bonds (allenes, dienes, enynes, or diynes).

HAL is a multi-disciplinary open access archive for the deposit and dissemination of scientific research documents, whether they are published or not. The documents may come from teaching and research institutions in France or abroad, or from public or private research centers. L'archive ouverte pluridisciplinaire HAL, est destinée au dépôt et à la diffusion de documents scientifiques de niveau recherche, publiés ou non, émanant des établissements d'enseignement et de recherche français ou étrangers, des laboratoires publics ou privés.

DEDICATÓRIA "Médico Cirurgião. 57 anos dedicados à medicina. No interior de Minas Gerais, foi pioneiro. De atendimentos e partos em vilarejos, às toracotomias com ombredane. Doutor íntegro, de extrema competência e habilidade. Calmo, dedicado e HUMANO. Praticou a medicina com benignidade e honradez. Sorte, tinham seus pacientes em tê-lo ao lado deles. Salvou muitas vidas. E trouxe outras tantas por suas mãos. Inclusive, eu.

Two new hexanuclear complexes involving two of the lightest lanthanide ions have been synthesized and structurally described. Their chemical formula is [Ln 6 (l 6 -O)(l 3 -OH) 8 (NO 3 ) 6 (H 2 O) 14 ] Á 2NO 3 Á 2H 2 O with Ln = Pr or Nd. The structure has been solved for the Pr 3+containing compound. It crystallizes in the monoclinic system, space group P21/n (no. 14) with a = 12.4163(2) A ˚, b = 10.51210(10) A ˚, c = 16.0389(2) A ˚, b = 95.7810( )°and Z = 4. The chemical and thermal stabilities of both the compounds have been studied. These studies reveal that they can be used as molecular chemical precursors for further materials synthesis. To the best of our knowledge, this praseodymium-containing hexanuclear complex is the first ever reported.

Two isoreticular metal-organic frameworks with chemical formulae [Cu(L)(4,4'-bipy)(H2O)]n 1.5nCH3CN (1) and [Cu(L)(4,4'-bipy)(H2O)]n·4nH2O (2) (H2L = diphenylmethane-4,4'-dicarboxylic acid) were synthesized and structurally characterized. They show the CdSO4 (6(5) 8) net and have an obvious 1D channel that is spread along the crystallographic c axis. More importantly, 1 shows high selectivity for H2 over N2 and CO2 at low pressure, which could be confirmed via computational calculations using the Connolly algorithm to reveal the size and shape of accessible voids. The incorporation of the drug 5-fluorouracil (5-FU) into the desolvated 1 was around 27.5 wt% per gram of the dehydrated 1. 5-FU is released in a highly controlled and progressive fashion with 61% of the drug released after 95 hours. In addition, we have applied molecular docking calculations to investigate the preferred conformation of 5-FU molecules upon binding to MOF 1. These calculations provide a structur...

a Isolated yields. b Determined by crude 1 H NMR. c Determined by HPLC using a chiral column. Table S2. Optimization of Stepwise One-pot [3 + 2] Cycloaddition Reaction NO 2 anti-7a 10 mol% [M]/1 solvent 20 mol% additive -15  C, 18h N Ph 3a (1.2 equiv) 6 (1 equiv) Ot-Bu

In a randomized double-blind study, Swiss adults traveling to tropical countries for 12 to 28 days took a solid formulation of bismuth subsalicylate (1.05 or 2.1 g/day on a twice-daily regimen) or placebo. Efficacy was evaluated in 231 volunteers. Diarrheal incidence was reduced by 41% in persons taking the high dose (P = 0.007) and by 35% in those taking the low dose (P = 0.03) with excellent compliance. No serious adverse reactions occurred, but objectionable taste, constipation, and nausea were seen more frequently with active medication (P = 0.04). Twenty patients provided stool samples: no bacteria were detected in the 8 volunteers who were on active medication, but various bacteria were found in 5 of the 12 patients who had taken placebo (P = 0.04).

The Mixed ligand metal complexes of chloroquine with ibuprofen and chloroquine with paracetamol were synthesized using transition metal ions, including Cu(II), Fe(III), Ni(II), and Mn(II). The study aimed to examine their coordination behaviour, physicochemical properties, and antifungal activities. The synthesized complexes were characterized using Fourier Transform Infrared (FTIR) spectroscopy, UV-Visible (UV-Vis) spectroscopy, and molar conductivity measurements. FTIR analysis showed notable shifts in characteristic functional group bands, particularly C=N, N-H, and C=O stretching vibrations, confirming coordination through nitrogen and oxygen donor atoms. UV-Vis spectra revealed changes in electronic transitions, including ligand-to-metal charge transfer and d-d transitions, indicating successful complex formation. Conductivity studies further provided insight into the electrolytic and electronic nature of the complexes in solution. The antifungal activities of both free ligands and their corresponding metal complexes were evaluated against Aspergillus niger and Aspergillus flavus using standard microbiological methods. The results showed that the metal complexes exhibited significantly enhanced antifungal activity compared to the free ligands. This improved activity was attributed to increased lipophilicity upon complexation, which enhances penetration through microbial cell membranes and improves biological effectiveness. In conclusion, the synthesized Cu(II), Fe(III), Mn(II), and Ni(II) mixed ligand complexes demonstrated promising antifungal properties, suggesting their potential application in pharmaceutical and medicinal chemistry for further development as antimicrobial agents.

The aim of this study was to investigate whether superoxide dismutase (SOD) enzymes and ascorbate play a role in the protection of the nitrergic relaxation against superoxide anion inhibition in the mouse duodenum. Methods: The effects of exogenous SOD, N,N'-bis(salicylidene) ethylenediamine chloride (EUK-8; a synthetic cell-permeable mimetic of the manganese SOD [Mn SOD] and ascorbate on relaxant responses induced by nitrergic nerve stimulation), exogenous nitric oxide (NO), and nitroglycerin were investigated in isolated mouse duodenum tissues. Results: Diethyldithiocarbamate (DETCA) inhibited the relaxation to exogenous NO and nitroglycerin, but not relaxation to electrical field stimulation (EFS). SOD and ascorbate partially prevented the inhibitory effect of DETCA on relaxation to NO, abut not to nitroglycerin. The DETCAinduced inhibition on nitroglycerin was prevented by EUK-8. Hemoglobin, 2-(4-carboxyphenyl)-4,4,5,5-tetramethylimidazolinel-oxyl-3-oxide, and hydroxocobalamin inhibited the relaxation to NO, but not to EFS and nitroglycerin in the presence of DETCA. Pyrogallol and hydroquinone inhibited the relaxation to NO, but not to EFS and nitroglycerin. This inhibition was prevented by exogenous SOD and ascorbate, but was not prevented by EUK-8. Pyrogallol and hydroquinone did not inhibit the EFS-induced relaxation in the presence of DETCA. Duroquinone and 6-anilino-5.8-quinolinedione inhibited the relaxation to EFS, NO, and nitroglycerin, and this inhibition was prevented by EUK-8. Conclusion: These results suggest that the nitrergic neurotransmission in the mouse duodenum is protected by endogenous tissue antioxidants against superoxide anions, and Mn SOD, in addition to copper/zinc SOD, can protect NO from attack from superoxide anion generators intracellularly. Also, the possibility that the endogenous neurotransmitter may not be the free NO but a NO-containing or NOgenerating molecule in the mouse duodenum remains open.

PURPOSE: To analyze the triple antimicrobial therapy in positive Helicobacter spp. dogs and to investigate recurrence. METHODS: A total of 20 dogs underwent endoscopy followed by gastric biopsy using the rapid urease test and histopathology stained with Giemsa. Ten animals were treated with triple therapy recommended for humans and divided into control and experimental group. The control group was kept in isolation while the experimental group was placed in contact with positive animals during 60 days. RESULTS: The prevalence of infection in animals in this experiment was 100%, and more frequent in the fundus and the gastric body. Therapy for 7 days using clarithromycin, amoxicillin and lansoprazole was effective in 100% of the animals. Recurrence of the infection in 80% of dogs in the experimental group, while the control group remained eradicated after 60 days. CONCLUSION: Crowded environments associated with close contact with dogs infected with helicobacter are a determinant for...

The purpose of this study was to assess the accuracy of phase-contrast MR angiography with gadolinium in evaluating the patency and blood flow direction of the portal venous system; the presence, extent, and type of varices; and the patency of surgical decompressive shunts in patients before liver transplantation. This information is essential in management and care of patients with chronic liver disease and portal hypertension and those who are candidates for liver transplantation. SUBJECTS AND METHODS. Twenty-four patients with portal venous hypertension were evaluated with phase-contrast MR angiography. Two patients had surgical splenorenal shunts and one had a mesocaval shunt. Phase-contrast angiograms were acquired as a series of two-dimensional sequential coronal sections during breath-holding and after IV administration of gadopentetate dimeglumine. Correlative findings from color flow Doppler sonography, contrast-enhanced CT scanning, and conventional angiography were available in 23, 20, and 10 patients, respectively, and were used as standards. The images from each technique were analyzed independently for patency of and flow direction in the portal vein, splenic vein, superior mesenteric vein, and surgically created shunts, and for detection, distribution, and extent of five variceal groups. RESULTS. Findings from phase-contrast MR angiography completely agreed with those of sonography, CT scanning, and conventional angiography. The main portal vein was patent in 18 patients, stenosed in one, partially thrombosed in one, and occluded in four. Phase-contrast MR angiography correctly showed hepatofugal flow in three patients and hepatopetal flow in 17 patients. Both the splenic and superior mesenteric veins were patent in 20, partially thrombosed in one, and occluded in three cases. Phase-contrast MR angiograms showed 85% of the variceal groups, and MR rating of variceai size was not significantly different from that of CT rating. Phase-contrast MR angiography correctly showed the patency of all three surgical decompressive shunts.

Climacostol is a natural toxin isolated from the freshwater ciliated protozoan Climacostomum virens and belongs to the group of resorcinolic lipids. Climacostol exerts a potent antimicrobial activity against a panel of bacterial and fungal pathogens. In addition it inhibits the growth of tumor cell lines in a dose-dependent manner by inducing programmed cell death via intrinsic pathway. In this work, we investigated the possibility that climacostol exerts a prooxidant effect, inducing plasmid DNA strand breakage and eukaryotic DNA damage in presence of Cu(II) ions. Inhibition of DNA breakage using SOD, catalase and neocuproine confirmed the involvement of reactive oxygen species and Cu(I) ions in the DNA damage. UV-visible absorption changes and mass spectrometric analysis identified a product of reaction as a deprotonated form of climacostol. Study of the interaction with DNA, using fluorescence spectroscopic techniques, showed that climacostol binds with DNA. Given the structure-activity relationship of this compound and the mechanism of its prooxidant effect, we propose that the Cu(II)-mediated oxidative DNA damage by climacostol could explain its antimicrobial and antiproliferative activity.

Superoxide dismutase (SOD) constitutes the first line of defense against oxidative stress by catalyzing the dismutation of superoxide anion radicals (O ₂ •⁻) into molecular oxygen and hydrogen peroxide. Since its discovery in 1969, SOD has been extensively characterized across species ranging from bacteria to mammals, revealing a family of metalloenzymes with distinct metal cofactors, subcellular localizations, and regulatory mechanisms. This comprehensive review synthesizes over five decades of research on SOD, encompassing its discovery history, molecular structure and classification, physicochemical properties, extraction and purification methodologies, pharmacokinetics, and multifaceted pharmacological actions. The therapeutic potential of SOD has been investigated in numerous pathological conditions, including aging, skin photoaging, cardiovascular diseases, neurodegenerative disorders, cancer, radiation injury, diabetic complications, and organ protection. Clinical trials have demonstrated both promise and limitations, with bioavailability remaining a central challenge. Recent advances in SOD mimetics, nanozyme formulations, and targeted delivery systems have opened new avenues for therapeutic application. This review critically evaluates the current state of knowledge, identifies gaps in understanding, and proposes future research directions to harness the full therapeutic potential of SOD.

HIGHLIGHTS • Serine proteases depend on a properly aligned Ser-His hydrogen-bond network; modeled Oγ-Hγ•••Nε2 geometries commonly fall in a ~115-140° productive range. • 2 0 7 A DNA/RNA polymerases depend on two Mg² ions spaced ~3.9 Å enabling near-linear phosphoryl transfer (160-180°). • 2 0 7 A Carbonic anhydrase II holds Zn² in a tetrahedral coordination (~109.5°) to activate a nucleophilic hydroxide for CO₂ hydration. • 2 0 7 A Adenylate kinase uses Mg² to reorient substrates by ~30°, directly adjusting reaction geometry for phosphoryl transfer. • Claims of ±0.5° angular precision (glycine cleavage T protein) remain unverified in primary structural literature and require independent high-resolution validation.

Tetrapod-shaped maghemite nanocrystals are synthesized by manipulating the decomposition of iron pentacarbonyl in a ternary surfactant mixture under mild thermal conditions. Adjustment of the reaction parameters allows for the systematic tuning of both the width and the length of the tetrapod arms, which grow preferentially along the 〈111〉 easy axis direction. Such degree of control leads to modulation of the magnetic behavior of the nanocrystals, which evolves systematically as their surface magnetization phase and shape anisotropy are progressively increased.

Global and regional longitudinal strain (GLS -RLS) assessed by two-dimensional speckle tracking echocardiography (2D-STE) are considered reliable indexes of left-ventricular (LV) function and myocardial viability in chronic ischaemic patients when compared with delayed-enhanced cardiac magnetic resonance (DE-CMR). In the present study, we tested whether GLS and RLS could also identify early myocardial dysfunction and transmural extent of myocardial scar in patients with acute ST elevation myocardial infarction (STEMI) and relatively preserved LV function. Twenty STEMI patients with LVEF ≥40%, treated with PPCI within 6 h from symptoms onset, underwent DE-CMR and 2D-echocardiography for 2D-STE analysis 6 + 2 days after STEMI. Wall motion score index (WMSI) and LV ejection fraction (LVEF) were calculated by both methods. Infarct size and transmural extent of necrosis were assessed by CMR. GLS and RLS were obtained by 2D-STE. Mean GLS of the study population was 214 + 3.3, showing a significant correlation with both LVEF and WMSI, by CMR (r ¼ 20.86, P ¼ 0.001, and r ¼ 0.80, P ¼ 0.001, respectively) and time-to-PCI (r ¼ 0.66, P ¼ 0.038). A weaker correlation was found between GLS and LVEF and WMSI assessed by 2D-echo (r ¼ 20.65, P ¼ 0.001, and r ¼ 0.53, P ¼ 0.013, respectively). RLS was significantly lower in DE-segments when compared with normal myocardium (P , 0.0001). A cutoff value of RLS of 212.3% by receiver-operating characteristic (ROC) curves identified DE-segments (sensitivity 82%, specificity 78%), whereas a cut-off value of 211.5% identified transmural extent of DE (sensitivity 75%, specificity 78%). Our findings indicate that RLS and GLS evaluation provides an accurate assessment of global myocardial function and of the presence of segments with transmural extent of necrosis, with several potential clinical implications.

The Escherichia coli genome encodes genes for seven different subunit species while only having single genes for the ␣, ␤, and ␤ subunits that make up the RNA polymerase core enzyme. The various factors compete for binding to the core enzyme, upon which they confer promoter DNA-specific transcription initiation to the polymerase. We have mapped a major interaction site between one of the species, 70 , and ␤. Using far-Western blotting analysis of chemically cleaved and genetically engineered protein fragments, we have identified a N-terminal fragment of ␤ (residues 60 -309) that could bind 70 . We were able to more precisely map the interaction domain to amino acid residues 260 -309 of ␤ using nickel nitrilotriacetic acid co-immobilization assays.

The oxidative electrochemistry of a variety of homo-and bimetallic group VI metal carbonyl compounds containing 1,1′-bis(diphenylphosphino)ferrocene (dppf) with the general formulas M(CO) 5 (dppf) (1a-c), M(CO) 4 (dppf) (2a-c), and (CO) 5 M(dppf)M′(CO) 5 (3a-f) (M, M′ ) Cr, Mo, W) was investigated. The effect of the group VI metal and the coordination mode of the dppf ligand on the potential at which the oxidation of the group VI metals and the ferrocene backbone of dppf occurred was examined.

Purpose: To evaluate the relative enhancement of liver, pancreas, focal nodular hyperplasia (FNH), pancreas-toliver index, and FNH-to-liver index in the hepatic arterial dominant phase (HADP) after injection of hepatocyte-specific MRI contrast agents, gadoxetic acid and gadobenate dimeglumine, on 3 and 1.5 Tesla (T) MRI in the same patient. The MRI database was retrospectively searched to identify consecutive patients who underwent abdominal MRI at 3T and 1.5T systems, using both 0.025 mmol/kg gadoxetic acid-enhanced and 0.05 mmol/kg gadobenate dimeglumine-enhanced MRI at the same magnetic strength field system. 22 patients were identified, 10 were scanned at 3T system and 12 at 1.5T system. The enhancement of liver, pancreas, and FNH was evaluated quantitatively on MR images. The relative enhancement of liver in HADP in the gadobenate dimeglumine-enhanced group in all subjects was significantly higher than that in gadoxetic acidenhanced group (P ¼ 0.023). The gadobenate dimeglumine-enhanced group in HADP had better relative enhancement of pancreas and FNH, pancreas-to-liver index, and FNH-to-liver index than gadoxetic acidenhanced group, but the difference was not statistically significant. The 0.05 mmol/kg gadobenate dimeglumine-enhanced abdominal MRI studies at 3T and 1.5T MR systems are superior in relative enhancement of the liver in HADP to 0.025 mmol/kg gadoxetic acid-enhanced MRI. This type of assessment may provide comparative effectiveness data.

Mn(BH 4 ) 2 was synthesized by am etathesis reaction (1), reacting MnCl 2 (99.999 %, Sigma Aldrich) and LiBH 4 (95 %, Sigma Aldrich) in the ratio 1:2s uspended in anhydrous diethyl ether,E t 2 O, for 12 h. Et 2 Ow as removed under vacuum at room temperature (RT)f or 1h.S ubsequently,d imethyl sulfide, S(CH 3 ) 2 ,( dehydrated, Sigma Aldrich) was added dissolving Mn(BH 4 ) 2 ,f ollowed by removal of solid LiCl by filtration. Finally,e xcess and coordinated S(CH 3 ) 2 was removed by using ar otary evaporator and subsequently heating the sample to 90 8Cu nder vacuum for 3-5 h. Thereby,d ry solvent-and halide-free Mn(BH 4 ) 2 was obtained. In order to avoid LiBH 4 in the reaction product, excess of MnCl 2 can be used. The dense polymorph of magnesium borohydride, a-Mg(BH 4 ) 2 ,a nd the porous g-Mg(BH 4 ) 2 ,w ere synthesized from dimethylsulfide borane (CH 3 ) 2 S•BH 3 and dibutylmagnesium, Mg(nBu) 2 ,t hrough the complex Mg(BH 4 ) 2 • 1 = 2 S(CH 3 ) 2 as described previously in the literature. Anhydrous NH 3 (g) was passed over the dry g-Mg(BH 4 ) 2 or Mn(BH 4 ) 2 for 2-3 ha tR Ty ielding M(BH 4 ) 2 •6NH 3 (M = Mg, Mn), which are denoted s1 and s2, respectively (Table ). Remaining LiBH 4 in the sample leads to formation of Li 2 Mn(BH 4 ) 2 •6NH 3 .A lternatively,a nhydrous NH 3 (g) was passed through the solution of Mn(BH 4 ) 2 in S(CH 3 ) 2 (denoted s3). Ammonia reacted immediately with the solution and aw hite precipitate formed. S(CH 3 ) 2 evaporated after 1h, and the white precipitate was dried under vacuum at RT for another 1-2 h. Mixtures of Mn(BH 4 ) 2 •6NH 3 -Mn(BH 4 ) 2 in the molar ratios (5:1), (4:2), (3:3), (2:4) and (1:5) were mechanochemically treated using aF ritz Pulverisette 6b all mill. These samples are denoted s4, s5, s6, s7 and s8, respectively.T he powders and tungsten carbide (WC) balls (mass ratio 1:30) were loaded in at ungsten carbide vial (80 mL) under inert conditions. The powders were ball-milled at 250 rpm for 2min intervened by a2min break and this sequence was repeated 60 times. Similarly,amixture of Mn(BH 4 ) 2 •6NH 3 -LiBH 4 (1:2) was ball-milled at 250 rpm for 2min followed by a2min pause repeated 60 times (s9). Am ixture of a-Mg(BH 4 ) 2 and Mn(BH 4 ) 2 in the ratio 1:1w as ball-milled (s10), and, subsequently,t he mixture was reacted with NH 3 (g) at RT for 2-3 h(s11).

A series of halide-free ammine manganese borohydrides, Mn(BH4 )2 ⋅nNH3 , n=1, 2, 3, and 6, a new bimetallic compound Li2 Mn(BH4 )4 ⋅6NH3 , and the first ammine metal borohydride solid solution Mg1-x Mnx (BH4 )2 ⋅6NH3 are presented. Four new crystal structures have been determined by synchrotron radiation powder X-ray diffraction and the thermal decomposition is systematically investigated for all the new compounds. The solid-gas reaction between Mn(BH4 )2 and NH3 provides Mn(BH4 )2 ⋅6NH3 . The number of NH3 per Mn has been varied by mechanochemical treatment of Mn(BH4 )2 ⋅6NH3 -Mn(BH4 )2 mixtures giving rise to increased hydrogen purity for n/m≤1 for M(BH4 )m ⋅nNH3 . The structures of Mg(BH4 )2 ⋅3NH3 and Li2 Mg(BH4 )4 ⋅6NH3 have been revisited and new structural models are presented. Finally, we demonstrate that ammonia destabilizes metal borohydrides with low electronegativity of the metal (χp <∼1.6), while metal borohydrides with high electronegativity (χp >∼1.6) are general...

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Case presentation: a 75-year-old man with a 10-year history of nodular goitre was referred for clinical evaluation. The ultrasound scan revealed enlarged thyroid right lobe almost fully filled with a heterogeneous nodule with numerous calcifications. Fine-needle aspiration biopsy suggested medullary thyroid carcinoma (MTC). Before the surgery the patient was referred to the nuclear medicine department and somatostatin receptor imaging (SRS; 68 Ga-DOTATATE) with PET/CT was performed. The scan demonstrated an increased uptake within the right thyroid mass. Subsequent PET/CT with 68 Ga-gastrin analogue (MG48) revealed the same indications as the SRS: an increased alveolar uptake in the right thyroid mass without the signs of lymph node metastases. The patient underwent total thyroidectomy and central lymph nodes dissection. Histopathology examination confirmed the presence of MTC with vascular invasion, but without lymph node metastases (pT3NoMx according to the 7 th edition of the AJCC Cancer Staging Manual). Immunohistochemical staining revealed positive reaction to calcitonin and CD56, whereas the reaction to thyroglobulin remained negative. The Ki-67 was 1%. Staining for SSTR2 and CCK2 showed high cytoplasmic expression in both cases. Knowledge of the presence of CCK2 receptor in MTC patients may be an important indication for the choice of diagnostic and therapeutic procedures. The presence of both the receptor types, cholecystokinin-2/gastrin and somatostatin, is possibly an interesting combination as far as the therapeutic target is concerned.

The kidneys play an essential role in PRRT. The infusion of amino acids could reduce uptake in the kidney of radiolabelled peptides. The purpose of this study was to determine the extent of kidney damage post PRRT. 53 patients, with disseminated neuroendocrine tumours (NET), received 3-5 cycles of up to a maximum 7.4 GBq/m2 calculated dose of 90Y-DOTATATE (n = 25) and 90Y/177Lu-DOTATATE (n = 28). Creatinine levels were measured and glomerular filtration rates (GFR) were calculated. A mixed amino acid infusion was used for nephroprotection. Patients treated with 90Y-DOTATATE had a mean creatinine level of 0.77 ± 0.19 mg/dL and a mean GFR (mL/min/1.73 m2) of 103.6 ± 30.8. Patients treated with 90Y/177Lu-DOTATATE had a mean creatinine level of 0.92 ± 0.33 mg/dL and a mean GFR of 84.7 ± 26.3. In the follow up, among patients treated with 90Y-DOTATATE and 90Y/177Lu-DOTATATE, the mean GFR level at 12 months was 101.2 ± 31.3 v. 83.9 ± 25.2, at 24 months 80.2 ± 32.7 v. 77.2 ± 31.1, at 36 mo...

The aim of this study was to assess the efficacy and toxicity of peptide receptor radionuclide therapy (PRRT) with the use of the high affinity somatostatin receptor subtype 2 analogue, (90)Y labelled Tyr3-octreotate, ((90)Y-DOTATATE) in neuroendocrine tumours (NETs). 46 patients with disseminated or non-operable NET were enrolled in this study. The (90)Y-DOTATATE therapeutic activity was calculated per total body surface area up to a total of 7.4 GBq/m(2) administered in three to five cycles, repeated every four to nine weeks. Before and after the therapy, blood tests for haematology, kidney and liver function, and chromogranin A were performed. Out of 46 (90)Y-DOTATATE treated patients, one died before completing the therapy and 16 died after completing the therapy, among them one due to myocardial infarction. After 12 month follow-up, stabilisation of disease was observed in 47%, partial remission in 31%, and progression in 9% of the 45 patients who completed the therapy. Five pa...

Purpose Peptide receptor radionuclide therapy (PRRT) using radiolabelled somatostatin analogues is a treatment option for patients with disseminated neuroendocrine tumours (NET). A combination treatment using the highenergy 90 Y beta emitter for larger lesions and the lower energy 177 Lu for smaller lesions has been postulated in the literature.The aim of the study was to evaluate combined 90 Y/ 177 Lu-DOTATATE therapy in comparison to 90 Y-DOTATATE alone. Methods Fifty patients with disseminated NET were included in the study prospectively and divided into two groups: group A (n=25) was treated with 90 Y-DOTATATE, whereas group B (n=25) received the 1:1 90 Y/ 177 Lu-DOTATATE. The administered activity was based on 3.7 GBq/m 2 body surface area in three to five cycles, with amino acid infusion for nephroprotection. The median overall survival time in group A was 26.2 months while in group B median survival was not reached. Overall survival was significantly higher in group B (p=0.027). Median event-free survival time in group A was 21.4 months and in group B 29.4 months (p>0.1). At the 12-month follow-up, comparison of group A vs group B showed stable disease (SD) in 13 vs 16 patients, disease regression (RD) in 5 vs 3 patients and disease progression (PD) in 3 vs 4 patients; 4 and 2 patients died, respectively. The 24-month follow-up results were SD in nine vs ten patients, RD in one patient vs none and PD in four patients in both groups; three and four patients died, respectively. Side effects were rare and mild. The results indicate that therapy with tandem radioisotopes ( 90 Y/ 177 Lu-DOTATATE) provides longer overall survival than with a single radioisotope ( 90 Y-DOTATATE) and the safety of both methods is comparable.

This work is devoted to deposition of alumina-silica films using an innovative pulsed injection metal organic chemical vapour deposition technique and aluminium tri(iso-propoxide) (Al(i-OPr) 3 ) and tetraethoxysilane (TEOS) as precursors. The deposited aluminium silicate films have been characterised by scanning electron microscopy, infrared spectroscopy, X-ray diffractometry and capacitance-voltage (C-V) measurements. The investigation of the deposition at different Si/Al ratios and substrate temperatures has shown that the growth rate increases with the increase of Al(i-OPr) 3 proportion in solution and decreases as the proportion of TEOS increases. We have also shown that aluminium content in the film increases at lower deposition temperatures while silicon content increases at higher temperatures. The permittivity of the films determined from C-V measurements decreases with increasing substrate temperature. It was found that films deposited at substrate temperatures of 600 or 700 °C and with the highest Si/Al ratio have the lowest dielectric permittivity. This research should be useful for further development of MOCVD technology for the deposition of aluminosilicate-based dielectric materials with controlled dielectric permittivity.

Alkoxy-and thiolato-bridged Re I molecular rectangles [{(CO) 3 Re(µ-ER) 2 Re(CO) 3 } 2 (µ-bpy) 2 ] (ER ) SC 4 H 9 , 1a; SC 8 H 17 , 1b; OC 4 H 9 , 2a; OC 12 H 25 , 2b; bpy ) 4,4′-bipyridine) exhibit strong interactions with several planar aromatic molecules. The nature of their binding was studied by spectral techniques and verified by X-ray diffraction analysis. Standard absorption and fluorescence titrations showed that a relatively strong 1:1 interaction occurs between aromatic guests such as pyrene and these rectangles. The results of a single-crystal X-ray diffraction analysis show that the recognition of 1 with a pyrene molecule is mainly due to CH‚‚‚π interactions and the face of the guest pyrene is located over the edges of the bpy linkers of 1. This is a fairly novel example of an interaction that is rarely designed into a host-guest pair. Furthermore, the interaction of 1 with Ag + results in the self-organization of supramolecular arrays, as revealed by solid-state data.

Purpose of Study: Methylene diphosphonate (MDP) radiolabeled with Technetium-99m (99mTc-MDP) is among the most widely used radiopharmaceuticals in oncology, primarily for the detection of skeletal metastases in patients with breast, prostate, and lung cancers. However, high costs, wastage of multidose kits, and dependency on cold-chain infrastructure hinder accessibility in low-resource oncology centers. This study assessed the stability and radiochemical purity (RCP) of fractionated MDP aliquots stored under ambient conditions, with the goal of establishing cost-effective strategies for sustainable nuclear oncology services. Materials and Methods: A prospective experimental laboratory-based study design was applied at the University Teaching Adult Hospital Nuclear Medicine Hot Laboratory, Zambia. Forty MDP aliquots prepared from kit fractionation were stored at ambient (15-32 °C), refrigerated (2-8 °C), and frozen (-23 °C) conditions. Aliquots were labeled with 99mTc and tested for RCP using instant thin-layer chromatography. Data were analyzed with Stata 14. Results: Ambient-stored MDP aliquots retained RCP values of 98-99% over 18 days, exceeding the WHO acceptance threshold of 90%. Refrigerated and frozen aliquots-maintained RCP values of 99-100% for 28 days. Statistical analysis using Pearson chi-square tests demonstrated significant differences in radiochemical purity with a p value of < 0.05. Conclusion: In oncology practice, where bone scintigraphy is indispensable for staging and therapy monitoring, ambient storage of fractionated MDP offers substantial cost saving mechanisms and practical solution in low-resource settings. This method reduces radiopharmaceutical wastage, mitigates reliance on cold-chain logistics, and enhances access to essential cancer diagnostics.