Supercritical carbon dioxide hops extracts with antimicrobial properties

Extracts obtained from hops (Humulus lupulus L., Cannabaceae) by supercritical fluid extraction (SFE), SFE followed by isomerization, as well as by conventional technique, were investigated for their chemical composition and antibacterial activity against selected foodborne pathogens and microorganisms capable to cause the food spoilage. The antibacterial activity of the extracts was compared with the antibacterial activity of xanthohumol, compound known for its broad pharmacological properties, isolated from the raw material remained after the SFE. Xanthohumol (XH, 96%) proved to posses the most prominent activity against all the tested strains, with the MIC values ranged between 2.5 and 20 mu g mL(-1). Supercritical hops extract and potassium isomerized supercritical hops extract showed strong antibacterial activity against the tested strains as well. Escherichia coli was not affected by the extracts, meaning that their oral admission would not cause the same problem as antibiotic application in intestinal flora. The chemical composition of the investigated hops extracts was analysed by GC-MS. Contents of a-acids, beta-acids, iso-alpha-acids and xanthohumol in the samples were determined by HPLC

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

Wettability and reactivity of ZrB2 substrates with liquid Al

Wetting characteristics of the Al/ZrB2 system were experimentally determined by the sessile drop method with application of separate heating of the ZrB2 and Al samples and combined with in situ cleaning of Al drop from native oxide film directly in vacuum chamber. The tests were performed in ultrahigh vacuum of 10−6 mbar at temperatures 710, 800, and 900 °C as well as in flowing inert gas (Ar) atmosphere at 1400 °C. The results evidenced that liquid Al does not wet ZrB2 substrate at 710 and 800 °C, forming high contact angles (θ) of 128° and 120°, respectively. At 900 °C, wetting phenomenon (θ < 90°) occurs in 29th minute and the contact angle decreases monotonically to the final value of 80°. At 1400 °C, wetting takes place immediately after drop deposition with a fast decrease in the contact angle to 76°. The solidified Al/ZrB2 couples were studied by scanning and transmission electron microscopy coupled with x-ray energy diffraction spectroscopy. Structural characterization revealed that only in the Al/ZrB2 couple produced at the highest temperature of 1400 °C new phases (Al3Zr, AlB2 and α-Al2O3) were formed

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

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

DNA damage to somatic cells of mice exposed to nonylphenol and to a combination of ionizing radiation and nonylphenol

Wprowadzenie. Nonylofenol (NF) występuje w produktach codziennego użytku zawierających polichlorek winylu (PCV). Narażenie ludzi na nonylofenol związane jest z jego obecnością w wodzie wodociągowej i żywności. Promieniowanie jonizujące pochodzi ze źródeł naturalnych oraz sztucznych, stosowanych szczególnie w medycynie oraz w nauce i przemyśle. Oba czynniki występują powszechnie w środowisku człowieka, dlatego ekspozycja na ich skojarzone działanie wydaje się wielce prawdopodobne. Cel badań. Celem badań było określenie wpływu subchronicznego podawania samcom myszy nonylofenolu oraz poddawania ich skojarzonemu działaniu promieniowania jonizującego i nonylofenolu na indukcję pęknięć nici DNA w komórkach somatycznych różnych narządów. Materiał i metoda. Materiał stanowiły myszy Pzh:SFIS, którym przez 8 tygodni, 5 razy w tygodniu podawano dootrzewnowo zawiesinę nonylofenolu w oleju słonecznikowym (25 mg/kg mc lub 50 mg/kg mc NF) lub poddawano je skojarzonemu działaniu promieniowania X i nonylofenolu (0,05 Gy + 25 mg/kg mc NF). Grupy zwierząt zabijano po 24 h oraz po 1, 4 i 8 tygodniach od zakończenia narażania. Z myszy izolowano szpik kostny, wątroby, nerki, płuca i śledziony. Oceny uszkodzeń DNA dokonano za pomocą testu kometowego. Wyniki. Na działanie nonylofenolu najbardziej wrażliwe okazały się limfocyty szpiku kostnego, mniej komórki śledziony i płuc. Nonylofenol nie indukował występowanie pęknięć nici DNA w komórkach wątroby i nerek. Ośmiotygodniowe skojarzone działanie promieniowania jonizującego i nonylofenolu w komórkach większości badanych narządów powodowało zwiększenie częstości występowania pęknięć nici DNA w porównaniu do skutków działania samego nonylofenolu. Spośród badanych komórek najbardziej wrażliwe na skojarzone działanie promieniowania jonizującego i nonylofenolu (0.05 Gy + 25 mg/kg mc NF dziennie) okazały się limfocyty szpiku kostnego i komórki śledziony, a najmniej komórki nerek i płuc. Wnioski. Nonylofenol indukuje uszkodzenia materiału genetycznego limfocytów szpiku kostnego oraz komórek śledziony i płuc. Skojarzone działanie promieniowania jonizującego i nonylofenolu powoduje występowanie pęknięć nici DNA limfocytów szpiku kostnego, komórek wątroby, płuc, śledziony i nerek, ze znacznie większą częstością niż sam nonylofenol. Uszkodzenia te mogą być więc stymulowane przez promieniowanie.Background. Nonylphenol (NP) has been found in daily used products reach in polyvinyl chloride (PVC). The main routes of human exposure are consumption of contaminated food and water. Radiation comes from natural and man-made sources, and is used in medicine, science and industry. Both agents are widely present in environment, therefore human exposure to their combined effect seems to be highly probable. Objective. The aim of the study was the estimation of the effects of subchronic exposure of male mice to nonylphenol alone and in a combination with ionizing radiation on the induction of DNA strand breaks of multiple somatic cells. Material and method. Pzh:SFIS male mice were exposed for 8 weeks, 5 days/week to nonylphenol alone (25 mg/kg bw or 50 mg/kg bw ) or in a combination with X-rays (0.05 Gy + 25 mg/kg bw NP). Animal were killed at 24 h, 1, 4 and 8 weeks after the end of exposure. The bone marrow, spleens, livers, kidneys and lungs were isolated from mice. The estimation of DNA damage was carried out by using Comet assay. Results. The most sensitive to nonylphenol occurred bone marrow lymphocytes, less sensitive were cells of spleen and lungs. NP did not induce the strand breaks in cells coming from liver and kidneys. Eight-weeks combined exposure to ionizing radiation and nonylphenol (0.05 Gy + 25 mg/kg bw NP) caused significantly enhanced level of DNA strand breaks in all tested cells. The most sensitive occurred bone marrow lymphocytes and spleen cells, whereas cells from kidneys and lungs were the least sensitive. Conclusion. Subchronic application of nonylphenol to mice induced damage to genetic material of bone marrow lymphocytes and cells of spleen and lungs. Combined exposure to ionizing radiation and nonylphenol caused, significantly higher than NP alone, level of DNA strand breaks of bone marrow lymphocytes, cells of liver, spleen, lungs and kidneys. Such damages might be stimulated by ionizing radiation

Frequency of micronuclei in erythrocytes of mice subchronic exposed to ionising radiation and nonylphenol

Celem pracy było określenie indukcji mikrojąder w retikulocytach i erytrocytach polichromatycznych myszy pod wpływem subchronicznej ekspozycji na promieniowanie X, nonylofenol (NF) lub na skojarzone działanie obu czynników. Myszy Pzh: SFIS narażane były przez 8 tygodni, 5 razy w tygodniu. Dawki wynosiły 0.05 Gy lub 0,10 Gy promieniowania X, 25 mg/kg mc lub 50 mg/kg mc nonylofenolu, a w przypadku skojarzonego działania 0,05 Gy + 25 mg/kg mc NF lub 0,10 Gy + 50 mg/kg mc NF. Zarówno promieniowania X, jak i NF działając oddzielnie indukowały powstawanie mikrojąder w retikulocytach i erytrocytach polichromatycznych myszy. Skojarzone działanie obu czynników w retikulocytach krwi obwodowej oraz w erytrocytach polichromatycznych szpiku kostnego indukowało zwiększoną częstość występowania mikrojąder w porównaniu do efektów działania każdego z czynników oddzielnie. W retikulocytach szpiku kostnego skojarzone działanie obu czynników w małych dawkach (0,05 Gy + 50 mg/kg mc NF) powodowało zwiększenie efektu mutagennego. Natomiast, w przypadku skojarzenia obu czynników w większych dawkach (0,10 Gy + 50 mg/kg mc NF), nonylofenol może wywierać efekt ochronny w stosunku do DNA retikulocytów powodując zmniejszenie uszkodzeń indukowanych przez promieniowanie X.The aim of the research was to investigate the level of micronuclei induction in reticulocytes and polychromatic erythrocytes of mice following subchronic exposure to X-rays, nonylphenol (NP) or to a combination of both. Male mice Pzh:SFIS were exposed during 8 weeks, 5 day per week to doses 0.05 Gy and 0.10 Gy of X-rays, 25 mg/kg mc and 50 mg/kg bw of nonylphenol as well as to 0.05 Gy + 25 mg/kg bw NP and 0.10 Gy + 50 mg/kg bw NP for combined exposure. Both X-rays and NP, acting alone induced micronuclei in reticulocytes and in polychromatic erythrocytes of mice. Combined X-rays-NP exposure of peripheral blood reticulocytes and bone marrow polychromatic erythrocytes caused enhanced frequency of micronuclei compared to the effect of each agent alone. In bone marrow reticulocytes, combined exposure in lower doses (0.05 Gy + 25 mg/kg bw NP) induced enhanced mutagenic effect. Contrary, after combined exposure to both agents in higher doses (0.10 Gy + 50 mg/kg bw NP), nonylphenol may protected DNA of reticulocytes against damage induced by X-rays