Aqua­(4,4′-bipyridine-κN)bis­(1,4-dioxo-1,4-dihydronaphthalen-2-olato-κ2 O 1,O 2)zinc 4,4′-bipyridine mono­solvate dihydrate

The reaction of 2-hy­droxy-1,4-naphtho­quinone and 4,4′-bipyridine with zinc acetate produced the title compound, [Zn(C10H5O3)2(C10H8N2)(H2O)]·C10H8N2·2H2O. The bond lengths and angles around the metal atom indicate a deviation from octa­hedral geometry. The two naphtho­quinone ligands coordinate in a cis fashion, with the 4,4′-bipyridine ligand and the water mol­ecules completing the coordination sphere of the metal atom. The asymmetric unit contains also one free 4,4′-bipyridine mol­ecule and two uncoordinated water mol­ecules. These mol­ecules make contacts with the complex through O—H⋯N and O—H⋯O hydrogen bonds, creating a layer two-dimensional network parallel to (121)

Adenosine A1-A2A receptor-receptor interaction: contribution to guanosine-mediated effects

Guanosine, a guanine-based purine nucleoside, has been described as a neuromodulator that exerts neuroprotective effects in animal and cellular ischemia models. However, guanosine's exact mechanism of action and molecular targets have not yet been identified. Here, we aimed to elucidate a role of adenosine receptors (ARs) in mediating guanosine effects. We investigated the neuroprotective effects of guanosine in hippocampal slices from A2AR-deficient mice (A2AR-/-) subjected to oxygen/glucose deprivation (OGD). Next, we assessed guanosine binding at ARs taking advantage of a fluorescent-selective A2AR antagonist (MRS7396) which could engage in a bioluminescence resonance energy transfer (BRET) process with NanoLuc-tagged A2AR. Next, we evaluated functional AR activation by determining cAMP and calcium accumulation. Finally, we assessed the impact of A1R and A2AR co-expression in guanosine-mediated impedance responses in living cells. Guanosine prevented the reduction of cellular viability and increased reactive oxygen species generation induced by OGD in hippocampal slices from wild-type, but not from A2AR-/- mice. Notably, while guanosine was not able to modify MRS7396 binding to A2AR-expressing cells, a partial blockade was observed in cells co-expressing A1R and A2AR. The relevance of the A1R and A2AR interaction in guanosine effects was further substantiated by means of functional assays (i.e., cAMP and calcium determinations), since guanosine only blocked A2AR agonist-mediated effects in doubly expressing A1R and A2AR cells. Interestingly, while guanosine did not affect A1R/A2AR heteromer formation, it reduced A2AR agonist-mediated cell impedance responses. Our results indicate that guanosine-induced effects may require both A1R and A2AR co-expression, thus identifying a molecular substrate that may allow fine tuning of guanosine-mediated responses

DNA-interacting properties of two analogous square-planar cis-chlorido complexes: copper versus palladium

Two square-planar coordination compounds, namely [Cu(CPYA)Cl2] (1) and [Pd(CPYA)Cl2] (2), were prepared from the ligand 4-chloro-N-(pyridin-2-ylmethyl)aniline (CPYA) and two chloride salts, and were fully characterized, including by X-ray diffraction. Spectroscopic, electrophoretic and AFM studies revealed that the two isostructural compounds were interacting differently with DNA. In both cases, the initial interaction involves electrostatic contacts of the CPYA ligand in the minor groove (as suggested by molecular docking), but subsequent strong binding occurs with the palladium(II) complex 2, whereas the binding with the copper complex 1 is weaker and concentration dependent. The strong binding of 2 eventually leads to the cleavage of the double strand and the redox activity of 1 allows to oxidatively cleave the biomolecule

Synthesis, characterization and catalytic activity of two novel cis-dioxovanadium(v) complexes: [VO2(L)] and [VO2(Hlox)]

Two novel complexes, [VO2(L)] (1) and [VO2(HLox)] (2), were synthesized and characterized by IV, UV-Vis and NMR spectroscopy, cyclic voltammetry, elemental analysis and X-ray diffraction. The synthesis of a new ligand, H2Lox, is also described. Complexes 1 and 2 were obtained by the reaction of [VO(acac)2] with the ligands HL and H2Lox, respectively. Alternatively, 2 was also obtained by the reaction of HL with [VO(acac)2] in the presence of hydroxylamine, and by the reaction of 1 with hydroxylamine. Crystallographic data show that complexes 1 and 2 have similar molecular structures, in which the cis-dioxovanadium(V) center is coordinated to L- or HLox-, respectively, in a distorted octahedral environment. The catalytic activity of these compounds towards cyclohexane oxidation was evaluated using H2O2 and t-BuOOH as oxidants. Both complexes presented > 70% selectivity for cyclohexylhydroperoxide formation. B3LYP/6-31G(d) calculations were used to confirm the geometry and to help assign the electronic spectra

A New Heterobinuclear FeIIICuII Complex with a Single Terminal FeIII–O(phenolate) Bond. Relevance to Purple Acid Phosphatases and Nucleases

A novel heterobinuclear mixed valence complex [Fe^IIICu^II(BPBPMP)(OAc)_2]ClO_4, 1, with the unsymmetrical N_5O_2 donor ligand 2-bis[{(2-pyridylmethyl)aminomethyl}-6-{(2-hydroxybenzyl)(2-pyridylmethyl)} aminomethyl]-4-methylphenol (H_2BPBPMP) has been synthesized and characterized. A combination of data from mass spectrometry, potentiometric titrations, X-ray absorption and electron paramagnetic resonance spectroscopy, as well as kinetics measurements indicates that in ethanol/water solutions an [Fe^III-(nu)OH-Cu^IIOH_2]+ species is generated which is the likely catalyst for 2,4-bis(dinitrophenyl)phosphate and DNA hydrolysis. Insofar as the data are consistent with the presence of an Fe_III-bound hydroxide acting as a nucleophile during catalysis, 1 presents a suitable mimic for the hydrolytic enzyme purple acid phosphatase. Notably, 1 is significantly more reactive than its isostructural homologues with different metal composition (Fe^IIIM^II, where M^II is Zn^II, Mn^II, Ni^II,or Fe^II). Of particular interest is the observation that cleavage of double-stranded plasmid DNA occurs even at very low concentrations of 1 (2.5 nuM), under physiological conditions (optimum pH of 7.0), with a rate enhancement of 2.7 x 10^7 over the uncatalyzed reaction. Thus, 1 is one of the most effective model complexes to date, mimicking the function of nucleases

COVID-19 in cancer patients: clinical characteristics and outcome—an analysis of the LEOSS registry

Introduction Since the early SARS-CoV-2 pandemic, cancer patients have been assumed to be at higher risk for severe COVID-19. Here, we present an analysis of cancer patients from the LEOSS (Lean European Open Survey on SARS-CoV-2 Infected Patients) registry to determine whether cancer patients are at higher risk. Patients and methods We retrospectively analyzed a cohort of 435 cancer patients and 2636 non-cancer patients with confirmed SARS-CoV-2 infection, enrolled between March 16 and August 31, 2020. Data on socio-demographics, comorbidities, cancer-related features and infection course were collected. Age-, sex- and comorbidity-adjusted analysis was performed. Primary endpoint was COVID-19-related mortality. Results In total, 435 cancer patients were included in our analysis. Commonest age category was 76–85 years (36.5%), and 40.5% were female. Solid tumors were seen in 59% and lymphoma and leukemia in 17.5% and 11% of patients. Of these, 54% had an active malignancy, and 22% had recently received anti-cancer treatments. At detection of SARS-CoV-2, the majority (62.5%) presented with mild symptoms. Progression to severe COVID-19 was seen in 55% and ICU admission in 27.5%. COVID-19-related mortality rate was 22.5%. Male sex, advanced age, and active malignancy were associated with higher death rates. Comparing cancer and non-cancer patients, age distribution and comorbidity differed significantly, as did mortality (14% vs 22.5%, p value < 0.001). After adjustments for other risk factors, mortality was comparable. Conclusion Comparing cancer and non-cancer patients, outcome of COVID-19 was comparable after adjusting for age, sex, and comorbidity. However, our results emphasize that cancer patients as a group are at higher risk due to advanced age and pre-existing conditions

Covid-19 triage in the emergency department 2.0: how analytics and AI transform a human-made algorithm for the prediction of clinical pathways

The Covid-19 pandemic has pushed many hospitals to their capacity limits. Therefore, a triage of patients has been discussed controversially primarily through an ethical perspective. The term triage contains many aspects such as urgency of treatment, severity of the disease and pre-existing conditions, access to critical care, or the classification of patients regarding subsequent clinical pathways starting from the emergency department. The determination of the pathways is important not only for patient care, but also for capacity planning in hospitals. We examine the performance of a human-made triage algorithm for clinical pathways which is considered a guideline for emergency departments in Germany based on a large multicenter dataset with over 4,000 European Covid-19 patients from the LEOSS registry. We find an accuracy of 28 percent and approximately 15 percent sensitivity for the ward class. The results serve as a benchmark for our extensions including an additional category of palliative care as a new label, analytics, AI, XAI, and interactive techniques. We find significant potential of analytics and AI in Covid-19 triage regarding accuracy, sensitivity, and other performance metrics whilst our interactive human-AI algorithm shows superior performance with approximately 73 percent accuracy and up to 76 percent sensitivity. The results are independent of the data preparation process regarding the imputation of missing values or grouping of comorbidities. In addition, we find that the consideration of an additional label palliative care does not improve the results

Soja integral processada de diferentes formas para uso em dietas para suínos em crescimento e terminação.

Projeto n. 03.04.11.200

An Unprecedented Fe-III(mu-OH)Zn-II Complex that Mimics the Structural and Functional Properties of Purple Acid Phosphatases

This communication reports the synthesis and X-ray structure of the first mixed-valence (FeZnII)-Zn-III complex containing the Fe-III(mu-OH)Zn-II structural unit. Based on the structure, physicochemical solution studies, and the catalytic properties toward the hydrolysis of the diester 2,4-bis(dinitrophenyl)phosphate (BDNPP), it is proposed that complex 1 employs a hydrolytic mechanism similar to that proposed for red kidney bean purple acid phosphatase, including a nucleophilic attack by the terminal, Fe-III-bound hydroxide and the concomitant release of 2,4-dinitrophenolate. Furthermore, it is demonstrated that the mu-hydroxo group in the {Fe-III(mu-OH)(mu-ROPO3)Zn-II} intermediate is unable to hydrolyze the monoester 2,4-dinitrophenylphosphate (DNPP), which suggests that the mu-hydroxo group is a significantly poorer nucleophile than the terminally Fe-III-bound OH- group