136 research outputs found
(Benzoato-κ2 O,O′)(quinoline-2-carboxylato-κ2 N,O)(quinoline-2-carboxylic acid-κ2 N,O)manganese(II)
The crystal structure of the title compound, [Mn(C7H5O2)(C10H6NO2)(C10H7NO2)], contains manganese(II) ions six-coordinated in a distorted octahedral environment. The equatorial plane is occupied by four O atoms, two from the carboxylate group of the benzoate ion, the other two from carboxylate/carboxyl groups of the quinaldate/quinaldic acid molecules. The axial positions are occupied by the N atoms of the quinoline ring systems. The metal ion lies on a twofold rotation axis that bisects the benzoate ligand; the quinaldate and quinaldic acid ligands are therefore equivalent by symmetry, and the carboxylate/carboxyl groups are disordered. The complexes are joined together by hydrogen bonds between the carboxylate/carboxyl groups of adjacent quinaldate/quinaldic acid molecules, forming zigzag chains that run along the c axis
The Effect of Contrast Medium SonoVue® on the Electric Charge Density of Blood Cells
The effect of contrast medium SonoVue® on the electric charge density of blood cells (erythrocytes and thrombocytes) was measured using a microelectrophoretic method. We examined the effect of adsorbed H+ and OH− ions on the surface charge of erythrocytes or thrombocytes. Surface charge density values were determined from electrophoretic mobility measurements of blood cells performed at various pH levels. The interaction between solution ions and the erythrocyte’s or thrombocyte’s surface was described by a four-component equilibrium model. The agreement between the experimental and theoretical charge variation curves of the erythrocytes and thrombocytes was good at pH 2–9. The deviation observed at a higher pH may be caused by disregarding interactions between the functional groups of blood cells
(Benzoato-κ2 O,O′)(quinoline-2-carboxylato-κ2 N,O)(quinoline-2-carboxylic acid-κ2 N,O)copper(II)
The crystal structure of the title compound, [Cu(C10H6NO2)(C7H5O2)(C10H7NO2)], contains copper(II) ions five-coordinated in a distorted trigonal-bipyramidal environment. The equatorial plane is occupied by three O atoms, one from the carboxylate group of the benzoate ion considered as occupying a single coordination site, the other two from two carboxylate groups of the quinaldic acid and quinaldate ligands. The axial positions are occupied by the N atoms of the quinoline ring system. The metal ion lies on a twofold axis that bisects the benzoate ion. The quinaldate and quinaldic acid ligands are equivalent by symmetry, and the carboxylate/carboxyl groups are disordered. The disordered H atom is shared between the carboxylate groups of adjacent quinaldic acid molecules. Such hydrogen bonds delineate zigzag chains that run along the c axis. The structure is very similar to that of the MnII analog
Cr cluster characterization in Cu-Cr-Zr alloy after ECAP processing and aging using SANS and HAADF-STEM
International audienceThe precipitation of nano-sized Cr clusters was investigated in a commercial Cu-1Cr-0.1Zr (wt.%) alloy processed by Equal-Channel Angular Pressing (ECAP) and subsequent aging at 550 °C for 4 hours using small angle neutron scattering (SANS) measurements and high-angle annular dark-field-scanning transmission electron microscopy (HAADF-STEM). The size and volume fraction of nano-sized Cr clusters were estimated using both techniques. These parameters assessed from SANS (d~3.2 nm, Fv~1.1 %) agreed reasonably with those from HAADF-STEM (d ~2.5 nm, Fv~2.3%). Besides nano-sized Cr clusters, HAADF-STEM technique evidenced the presence of rare cuboid and spheroid sub-micronic Cr particles about 380-620 nm mean size. Both techniques did not evidence the presence of intermetallic CuxZry phases within the aging conditions
Bis[(2-quinolyl)methanediol-κ2 N,O](sulfato-κO)copper(II) dihydrate
In the title compound, [Cu(SO4)(C10H9NO2)2]·2H2O, the CuII ion is chelated by two (2-quinolyl)methanediol ligands and coordinated by a monodentate sulfate ligand in a distorted trigonal–bipyramidal environment, with O atoms occupying the equatorial sites and N atoms in the axial sites. The dihedral angle between the two essentially planar quinoline ring systems is 45.02 (9)°. In the crystal structure, an extensive O—H⋯O hydrogen-bonding network forms layers parallel to the ab plane
DNA damage in circulating leukocytes measured with the comet assay may predict the risk of death
The comet assay or single cell gel electrophoresis, is the most common method used to measure strand breaks and a variety of other DNA lesions in human populations. To estimate the risk of overall mortality, mortality by cause, and cancer incidence associated to DNA damage, a cohort of 2,403 healthy individuals (25,978 person-years) screened in 16 laboratories using the comet assay between 1996 and 2016 was followed-up. Kaplan-Meier analysis indicated a worse overall survival in the medium and high tertile of DNA damage (p < 0.001). The effect of DNA damage on survival was modelled according to Cox proportional hazard regression model. The adjusted hazard ratio (HR) was 1.42 (1.06-1.90) for overall mortality, and 1.94 (1.04-3.59) for diseases of the circulatory system in subjects with the highest tertile of DNA damage. The findings of this study provide epidemiological evidence encouraging the implementation of the comet assay in preventive strategies for non-communicable diseases
Changes in Phospholipid Composition Studied by HPLC and Electric Properties of Liver Cell Membrane of Ethanol-Poisoned Rats
Ethanol introduced into the organism undergoes rapid metabolism to acetaldehyde and then to acetic acid. The process is accompanied by formation of reactive oxygen species (ROS), which damage mainly lipids of membrane cells. The effects of ROS can be neutralized by administering preparations with antioxidant properties. The natural preparations of this kind are teas
Prognostic model to predict postoperative acute kidney injury in patients undergoing major gastrointestinal surgery based on a national prospective observational cohort study.
Background: Acute illness, existing co-morbidities and surgical stress response can all contribute to postoperative acute kidney injury (AKI) in patients undergoing major gastrointestinal surgery. The aim of this study was prospectively to develop a pragmatic prognostic model to stratify patients according to risk of developing AKI after major gastrointestinal surgery. Methods: This prospective multicentre cohort study included consecutive adults undergoing elective or emergency gastrointestinal resection, liver resection or stoma reversal in 2-week blocks over a continuous 3-month period. The primary outcome was the rate of AKI within 7 days of surgery. Bootstrap stability was used to select clinically plausible risk factors into the model. Internal model validation was carried out by bootstrap validation. Results: A total of 4544 patients were included across 173 centres in the UK and Ireland. The overall rate of AKI was 14·2 per cent (646 of 4544) and the 30-day mortality rate was 1·8 per cent (84 of 4544). Stage 1 AKI was significantly associated with 30-day mortality (unadjusted odds ratio 7·61, 95 per cent c.i. 4·49 to 12·90; P < 0·001), with increasing odds of death with each AKI stage. Six variables were selected for inclusion in the prognostic model: age, sex, ASA grade, preoperative estimated glomerular filtration rate, planned open surgery and preoperative use of either an angiotensin-converting enzyme inhibitor or an angiotensin receptor blocker. Internal validation demonstrated good model discrimination (c-statistic 0·65). Discussion: Following major gastrointestinal surgery, AKI occurred in one in seven patients. This preoperative prognostic model identified patients at high risk of postoperative AKI. Validation in an independent data set is required to ensure generalizability
Improved clinical investigation and evaluation of high-risk medical devices: the rationale and objectives of CORE-MD (Coordinating Research and Evidence for Medical Devices)
: In the European Union (EU) the delivery of health services is a national responsibility but there are concerted actions between member states to protect public health. Approval of pharmaceutical products is the responsibility of the European Medicines Agency, whereas authorizing the placing on the market of medical devices is decentralized to independent 'conformity assessment' organizations called notified bodies. The first legal basis for an EU system of evaluating medical devices and approving their market access was the medical device directives, from the 1990s. Uncertainties about clinical evidence requirements, among other reasons, led to the EU Medical Device Regulation (2017/745) that has applied since May 2021. It provides general principles for clinical investigations but few methodological details-which challenges responsible authorities to set appropriate balances between regulation and innovation, pre- and post-market studies, and clinical trials and real-world evidence. Scientific experts should advise on methods and standards for assessing and approving new high-risk devices, and safety, efficacy, and transparency of evidence should be paramount. The European Commission recently awarded a Horizon 2020 grant to a consortium led by the European Society of Cardiology and the European Federation of National Associations of Orthopaedics and Traumatology, that will review methodologies of clinical investigations, advise on study designs, and develop recommendations for aggregating clinical data from registries and other real-world sources. The CORE-MD project (Coordinating Research and Evidence for Medical Devices) will run until March 2024; here we describe how it may contribute to the development of regulatory science in Europe
Lycopene - antioxidant with radioprotective and anticancer properties. A review
Ionizing radiation may cause damage to living tissue by producing free radicals like reactive oxygen species (ROS). ROS can
randomly react with lipids, proteins and nucleic acids of cell causing oxidative stress and damage in these macromolecules,
leading to pathogenesis of chronic diseases and age related and also cancer. The first line of defense from the damaging
effects of ROS is antioxidants, which convert the oxidants to less reactive species. Lycopene (LYC) is an acyclic isomer
of beta-carotene. It synthesized by plants or autotrophic bacteria but not by animals. Red fruits and vegetables, including
tomatoes, watermelons, pink grapefruits, apricots, pink guavas and papaya contain LYC. This carotenoid has very strong
antioxidant properties. The many studies confirm that dietary supplementation with LYC reduces risk of cancers of many
organs, but also retard the growth of the tumors. LYC has also chemopreventive effects against other diseases such as
cardiovascular disease, osteoporosis, male infertility and inhibits the toxic action of other agents. Numerous in vitro and
animal studies showed that LYC may provide protection against damages induced by ionizing radiation. It suggests that
supplementation of LYC might be useful in diminishing of negative effect of cancer radiotherapy or in mitigating the effects
of possible radiation accidents on human health.Promieniowanie jonizujące może powodować uszkodzenia żywej tkanki poprzez wytwarzanie wolnych rodników takich jak
reaktywne formy tlenu (RFT). RFT mogą przypadkowo wchodzić w reakcję z lipidami, białkami lub kwasami nukleinowymi
komórki, powodując stres oksydacyjny i uszkodzenia w tych makrocząsteczkach, co prowadzi do patogenezy chorób przewlekłych
i związanych z wiekiem, a także do zachorowania na raka. Pierwsza linia obrony przed szkodliwym działaniem
RFT to przeciwutleniacze, które przekształcają utleniacze do form mniej reaktywnych. Likopen (LYC) jest acyklicznym
izomerem beta-karotenu. Jest on syntetyzowany przez rośliny i bakterie autotroficzne, ale nie przez zwierzęta. Czerwone
owoce i warzywa, w tym pomidory, arbuzy, różowe grejpfruty, morele, papaja i różowe guawy zawierają LYC. Ten karotenoid
ma bardzo silne właściwości antyoksydacyjne. Liczne badania potwierdzają, że suplementacja LYC zmniejsza ryzyko raka
wielu narządów, a także opóźnia wzrost guza. LYC ma działanie zapobiegawcze również przeciwko innym chorobom, takim
jak choroby układu krążenia, osteoporoza, niepłodność, oraz hamuje toksyczne działanie innych czynników. Badania in vitro
i nad zwierzętami wykazały, że LYC może zapewnić ochronę przed uszkodzeniami indukowanymi przez promieniowanie
jonizujące. Sugeruje to, że suplementacja LYC może być przydatna w zmniejszaniu negatywnego wpływu radioterapii na
zdrowie człowieka lub w łagodzeniu skutków ewentualnych wypadków radiacyjnych
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