11 research outputs found

    DETERMINATION OF THE POLYPHENOL OXIDASE ACTIVITY IN RELATIONSHIP TO TOTAL PHENOLIC AND ANTHOCYANIN CONTENT OF SOME ROMANIAN VINE VARIETIES (VITIS VINIFERA L.) FOR TABLE GRAPES

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    The undesirable change in the grape colour, flavour and texture is associated with the enzymes polyphenol oxidase. Therefore, it is important to control their effect, as well as to establish their characteristics associated to the fruits. Grapes (skin, pulp and seeds) of ten Romanian vine varieties for table grapes (Splendid, Cetăţuia, Milcov, Transilvania, Someşan, Napoca, Gelu, Coarnă neagră selecţionată, Purpuriu and Radames) which are grown in the Ampelographic colection of University of Agricultural Sciences and Veterinary Medicine Iaşi, Romania, were analyzed for determination of polyphenol oxidase activities, total phenolics (flavonoids and non-flavonoids) and total monomeric anthocyanin content. Total phenolic content was higher in seeds, ranging from 4.36 to 5.35 g gallic acid equivalent/100 g fresh weight, of which flavonoids were between 65 and 88%. The highest polyphenol oxidase activity was determined in the grape extract of Radames variety (7.11 U/g/min), while total anthocyanin content was the most important in Napoca variety grape skins (343.86 mg cyanidin-3-glucoside equivalent/100 g fresh weight). There were found strong negative correlations between polyphenol oxidase activity (PA) and anthocyanin content (R 2 =0.8854) as well as between PA and total phenolic content of grape skins (R 2 =0.8586) and pulp (R 2 =0.8831), emphasizing the destructive effect of the enzyme on these chemical classes of compounds

    Globalization – a Cause or a Solution for Corona Economic Crisis

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    Research background: Since the extension of the Corona virus there are people saying that all this is happening because of globalisation, phenomena that diminished the control of states at the borders, lack of strong internal security rules, loose of political responsibility and decisions, etc. In this paper we investigated the situation from different economical perspectives and we clearly show the existence of positive effects of globalization. We will never know certainly enough at which percentage the current crisis results from a mismatch between the intensity of economic and human exchanges and the inability of public authorities to be prepared and take fast and appropriate decisions. It is well accepted that in a globalized world, interdependence prevails over sovereignty. Purpose of the article: We will analyse if this reality is really one of the main problems which cause the current disaster. Nevertheless, it would be too easy to blame only the lacks of effective globalization, much complicated is to identify the problem and solve it. Searching if the globalization is the cause or the solution may be interesting since from the political side, we will see a wave of critics and sceptics, many politicians will try to reposition in order to gain visibility and votes. Methods: Using descriptive and comparative analysis we demonstrate that societies may obtain greater benefits from cooperation, collaboration and integration, even in pandemic times. Findings & Value added: In a global world, we can see that borders do not protect against a pandemic and that all the major challenges facing humanity can only be solved by multilateral systems and by multilateral negotiation. We clearly demonstrated that global society has greater benefits from cooperation, collaboration and integration

    Solid-Phase Synthesized Copolymers for the Assembly of pH-Sensitive Micelles Suitable for Drug Delivery Applications

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    Diblock copolymers of polyhistidine are known for their self-assembly into micelles and their pH-dependent disassembly due to the amphiphilic character of the copolymer and the unsaturated imidazole groups that undergo a hydrophobic-to-hydrophilic transition in an acidic pH. This property has been largely utilized for the design of drug delivery systems that target a tumor environment possessing a slightly lower extracellular pH (6.8–7.2). The main purpose of this study was to investigate the possibility of designed poly(ethylene glycol)-polyhistidine sequences synthesized using solid-phase peptide synthesis (SPPS), to self-assemble into micelles, to assess the ability of the corresponding micelles to be loaded with doxorubicin (DOX), and to investigate the drug release profile at pH values similar to a malignant extracellular environment. The designed and assembled free and DOX-loaded micelles were characterized from a physico-chemical point of view, their cytotoxicity was evaluated on a human breast cancer cell line (MDA-MB-231), while the cellular areas where micelles disassembled and released DOX were assessed using immunofluorescence. We concluded that the utilization of SPPS for the synthesis of the polyhistidine diblock copolymers yielded sequences that behaved similarly to the copolymeric sequences synthesized using ring-opening polymerization, while the advantages of SPPS may offer facile tuning of the histidine site or the attachment of a large variety of functional molecules

    Injectable Thixotropic β–Cyclodextrin–Functionalized Hydrogels Based on Guanosine Quartet Assembly

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    Facile method for the preparation of β–cyclodextrin–functionalized hydrogels based on guanosine quartet assembly was described. A series of seven hydrogels were prepared by linking β–cyclodextrin molecules with guanosine moieties in different ratios through benzene–1,4–diboronic acid linker in the presence of potassium hydroxide. The potassium ions acted as a reticulation agent by forming guanosine quartets, leading to the formation of self–sustained transparent hydrogels. The ratios of the β–cyclodextrin and guanosine components have a significant effect on the internal structuration of the components and, correspondingly, on the mechanical properties of the final gels, offering a tunablity of the system by varying the components ratio. The insights into the hydrogels’ structuration were achieved by circular dichroism, scanning electron microscopy, atomic force microscopy, and X–ray diffraction. Rheological measurements revealed self–healing and thixotropic properties of all the investigated samples, which, in combination with available cyclodextrin cavities for active components loading, make them remarkable candidates for specific applications in biomedical and pharmaceutical fields. Moreover, all the prepared samples displayed selective antimicrobial properties against S. aureus in planktonic and biofilm phase, the activity also depending on the guanosine and cyclodextrin ratio within the hydrogel structure

    Comparison Adsorption of Cd (II) onto Lignin and Polysaccharide-Based Polymers

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    Given the predominantly negative impact of heavy metals on living organisms, the present study proposed to evaluate the adsorption performances under static conditions of Cd (II) from aqueous solutions on unmodified Sarkanda grass lignin compared to the adsorption performances of polysaccharide polymers chemically functionalized, obtained by synthesis and in their native state, but which, although effective, have a cost price that does not allow for large-scale expansion. To improve the retention of Cd (II) on this aromatic component of the biomass resulting from the processing of lignocellulosic materials, different experimental conditions (pH, concentration, dose and contact time) were followed. The Freundlich and Langmuir isotherms were used to describe the equilibrium conditions. Adsorption kinetics were assessed using the Lagergren I and Ho and McKay II kinetic models, furnishing informative insights into the process mechanism. Lignin adsorption capacity was also analyzed by performing biological tests on tomato seeds (Lypercosium esculentum), since heavy metals are known to be a stress factor for seeds by disturbing the osmotic equilibrium. Through the prism of the investigated parameters and under precisely established experimental conditions, unmodified Sarkanda grass lignin—an aromatic biopolymer—can be recommended as a promising adsorbent for the retention of Cd (II) from aqueous solutions, successfully replacing polysaccharide, especially cellulose-based polymers

    The Role of Presepsin and Procalcitonin in Early Diagnosis of Bacterial Infections in Cirrhotic Patients with Acute-on-Chronic Liver Failure

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    Background and Objectives: Bacterial infections represent one of the most frequent precipitating events of acute-on-chronic liver failure (ACLF) in a patient with liver cirrhosis (LC). Early diagnosis and treatment could influence the ACLF reversal rate and decrease the mortality rate in these patients. The study aimed to evaluate the role of presepsin, C-reactive protein (CRP), and procalcitonin (PCT) in the early diagnosis of bacterial infections in patients with LC and ACLF, defined according to the European Association for the Study of the Liver-Chronic Liver Failure Consortium (EASL-CLIF) criteria. Material and Methods: We performed a prospective observational study including all consecutive cirrhotic patients with ACLF admitted to our tertiary university center. The patients were follow-up until discharge. All patients were screened for infection at admission, and we included patients with community-acquired or healthcare-associated bacterial infections. Results: In this study, we included 153 patients with a median age of 60 years, of whom 65.4% were male. Infections were diagnosed in 71 patients (46.4%). The presepsin, CRP, and PCT levels were higher in patients with infections than in those without infections (p < 0.001, p = 0.023, and p < 0.001, respectively). The ROC analysis results demonstrated that the best cut-offs values for infections diagnosis were for presepsin 2300 pg/mL (sensitivity of 81.7%, specificity of 92.7%, AUROC 0.959, p < 0.001), CRP 5.3 mg/dL (sensitivity of 54.9%, specificity of 69.6%, AUROC 0.648, p = 0.023), and PCT 0.9 ng/mL (sensitivity of 80.3%, specificity of 86.6%, AUROC 0.909, p < 0.001). Presepsin (OR 3.65, 95%CI 1.394–9.588, p = 0.008), PCT (OR 9.79, 95%CI 6.168–25.736, p < 0.001), and MELD score (OR 7.37, 95%CI 1.416–18.430, p = 0.018) were associated with bacterial infections in patients with ACLF. Conclusion: Presepsin level ≥2300 pg/mL and PCT level ≥0.9 ng/mL may be adequate non-invasive tools for the early diagnosis of infections in cirrhotics with ACLF

    The Role of Presepsin in Diagnosing Infections in Patients with Liver Cirrhosis and Overt Hepatic Encephalopathy

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    Infections and sepsis represent severe liver cirrhosis (LC) complications and the precipitating factors of hepatic encephalopathy (HE). The early diagnosis and treatment of infections in patients with LC and HE can significantly increase their survival. Presepsin is a serum biomarker evaluated for the early diagnosis of infections and sepsis in the general and cirrhotic populations. This study aimed to evaluate the role of presepsin in the early diagnosis of infections in patients with LC and HE. This prospective observational study included all consecutive cirrhotic patients admitted to our tertiary university center with overt HE. The patients were follow-up until discharge. In this study, we included 365 patients with a median age of 59 years, of whom 61.9% were male. Infections were diagnosed in 134 patients (36.7%). The presepsin level was higher in patients with infections than those without infections (3167 vs. 500, p < 0.001). The ROC analysis results demonstrated that the best cut-off value for presepsin in infections detection was 980 pg/mL with a sensitivity of 80.17%, specificity of 82.5% (AUROC 0.869, CI 95%: 0.819–0.909, p < 0.001, Youden index J of 0.622), a positive predictive value of 40.63%, and a negative predictive value of 96.53%. In conclusion, in patients with LC and overt HE, presepsin levels >980 pg/mL could enhance the suspicion of bacterial infections. Presepsin may be an adequate non-invasive tool for the early diagnosis of infections in patients with LC and overt HE
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