BIOCHEMICAL AND HISTOLOGICAL EFFECTS OF DELTAMETHRIN EXPOSURE ON THE GILLS OF CARASSIUS AURATUS GIBELIO (Pisces Cyprinidae)

This study investigated the alterations in the activities of several antioxidant enzymesin the gills of the freshwater fish Carassius auratus gibelio exposed to deltamethrin.To get this goal, groups of 10 individuals were exposed for one, two, three, sevenand fourteen days to sublethal concentration of deltamethrin (2 g/L). Anothergroup was used as control. The activities of catalase, gluthatione peroxidase andgluthatione reductase were significantly decreased, while the glutathione-Stransferasewas up-regulated. All fish, exposed to 2glL deltamethrin revealed gillsmorphological alterations after 48h of exposure which were accentuated after 14days. In the gills hyperemia, fusion of secondary lamellae, epithelial layer ruptureand chloride cells proliferation were observed. These results suggest that animmediate adaptive response to the oxidative stress appeared, demonstratingalterations in the antoxidant defense mechanism in the gills of deltamethrinintoxicated fish

PROPEPTIDUL AMINO-TERMINAL AL PROCOLAGENULUI TIP I LA PACIENŢII CU DEFICIT DE HORMON DE CREŞTERE ÎN PERIOADA DE TRANZIŢIE

Introducere. Achiziţia de masă osoasă continuă şi după atingerea taliei finale în perioada de tranziţie. Deficitul de hormon de creştere (GHD) pare să aibă un efect semnificativ asupra turnover-ului colagenului în timpul copilăriei şi mai puţin în timpul maturităţii. Propeptidul amino terminal al colagenului tip I (P1NP) este un marker de formare osoasă cu variabilitate intraindividuală scăzută faţă de IGF1. Subiecţi şi metodă. 17 pacienţi de sex masculin diagnosticaţi în timpul copilăriei cu GHD, retestaţi în perioada de tranziţie, au fost evaluaţi la minimum 3 luni de la întreruperea tratamentului cu GH. Am evaluat corelaţia P1NP cu IGF1. Am determinat puterea predictivă a P1NP în identificarea pacienţilor cu deficit de GH persistent. Rezultate. Am găsit o corelaţie pozitivă puternică între P1NP şi IGF-1 în grupul de pacienţi care au menţinut deficitul de GH în perioada de adult tânăr (r = 0,72, CI [0,02 la 0,94], p = 0,046). O valoare prag pentru P1NP de - 0,66 SDS prezice persistenţa deficitului de GH cu o sensibilitate de 62,5% CI [24,5 la 91,5], specificitate de 75% CI [47,6 la 92,7] şi AUC = 0,719 CI [0,5 la 0,881], p<0,05. Nu am găsit o diferenţă semnificativă atunci când am comparat AUC pentru cei 2 parametri (p = 0.29). Concluzii. În perioada de tranziţie, atunci când viteza de creştere nu mai este disponibilă, dinamica P1NP în timpul terapiei substitutive cu GH ar putea fi utilă în cuantificarea eficienţei tratamentului

Bio-and hemo-compatible silk fibroin pegylated nanocarriers for 5-fluorouracil chemotherapy in colorectal cancer:In vitro studies

5-fluorouracil (5-FU) remains the gold standard of treatment for colorectal cancer, but its poor bioavailability and high systemic toxicity highlight the urgent need for the development of novel delivery strategies to increase the efficacy of 5-FU treatment. The present study is aimed to design and validate a PEGylated Silk Fibroin Nanocarrier (SF/PEG nanoparticles (NPs)) as an efficient 5-FU delivery system for potential intravenous administration. Using the human adenocarcinoma HT–29 cell line as an in vitro model for colorectal cancer, the cytotoxicity screening of the SF/PEG NPs showed that pristine nanocarriers were highly biocompatible, while the addition of 5-FU triggers a dramatic reduction in tumor cell viability, proliferation potential and mitochondrial integrity as well as a significant increase in nitric oxide production. Despite their high in vitro cytotoxicity, the 5-FU SF/PEG NPs were found hemocompatible as no impact on red blood cells hemolysis or the phagocytic activity of the granulocytes was observed. Exposure of HT–29 tumor cells and blood samples to 5-FU SF/PEG NPs augmented the tumor necrosis factor-α levels. Moreover, 5-FU SF/PEG NPs showed an impact on tumor cell migration and invasive potential as both of these processes were inhibited by the NP treatment

Efficient cellular and humoral immune response and production of virus-neutralizing antibodies by the Hepatitis B Virus S/preS1 16-42 antigen

Despite the availability of improved antiviral therapies, infection with Hepatitis B virus (HBV) remains a3 significant health issue, as a curable treatment is yet to be discovered. Current HBV vaccines relaying on the efficient expression of the small (S) envelope protein in yeast and the implementation of mass vaccination programs have clearly contributed to containment of the disease. However, the lack of an efficient immune response in up to 10% of vaccinated adults, the controversies regarding the seroprotection persistence in vaccine responders and the emergence of vaccine escape virus mutations urge for the development of better HBV immunogens. Due to the critical role played by the preS1 domain of the large (L) envelope protein in HBV infection and its ability to trigger virus neutralizing antibodies, including this protein in novel vaccine formulations has been considered a promising strategy to overcome the limitations of S only-based vaccines. In this work we aimed to combine relevant L and S epitopes in chimeric antigens, by inserting preS1 sequences within the external antigenic loop of S, followed by production in mammalian cells and detailed analysis of their antigenic and immunogenic properties. Of the newly designed antigens, the S/preS116–42 protein assembled in subviral particles (SVP) showed the highest expression and secretion levels, therefore, it was selected for further studies in vivo. Analysis of the immune response induced in mice vaccinated with S/preS116–42- and S-SVPs, respectively, demonstrated enhanced immunogenicity of the former and its ability to activate both humoral and cellular immune responses. This combined activation resulted in production of neutralizing antibodies against both wild-type and vaccine-escape HBV variants. Our results validate the design of chimeric HBV antigens and promote the novel S/preS1 protein as a potential vaccine candidate for administration in poor-responders to current HBV vaccines.publishedVersio

Influence of Irradiance, Flow Rate, Reactor Geometry, and Photopromoter Concentration in Mineralization Kinetics of Methane in Air and in Aqueous Solutions by Photocatalytic Membranes Immobilizing Titanium Dioxide

Photomineralization of methane in air (10.0–1000 ppm (mass/volume) of C) at100%relative humidity (dioxygen as oxygen donor) was systematically studied at318±3 K in an annular laboratory-scale reactor by photocatalytic membranes immobilizing titanium dioxide as a function of substrate concentration, absorbed power per unit length of membrane, reactor geometry, and concentration of a proprietary vanadium alkoxide as photopromoter. Kinetics of both substrate disappearance, to yield intermediates, and total organic carbon (TOC) disappearance, to yield carbon dioxide, were followed. At a fixed value of irradiance (0.30 W⋅cm-1), the mineralization experiments in gaseous phase were repeated as a function of flow rate (4–400 m3⋅h−1). Moreover, at a standard flow rate of 300 m3⋅h−1, the ratio between the overall reaction volume and the length of the membrane was varied, substantially by varying the volume of reservoir, from and to which circulation of gaseous stream took place. Photomineralization of methane in aqueous solutions was also studied, in the same annular reactor and in the same conditions, but in a concentration range of 0.8–2.0 ppm of C, and by using stoichiometric hydrogen peroxide as an oxygen donor. A kinetic model was employed, from which, by a set of differential equations, four final optimised parameters,k1andK1,k2andK2, were calculated, which is able to fit the whole kinetic profile adequately. The influence of irradiance onk1andk2, as well as of flow rate onK1andK2, is rationalized. The influence of reactor geometry onkvalues is discussed in view of standardization procedures of photocatalytic experiments. Modeling of quantum yields, as a function of substrate concentration and irradiance, as well as of concentration of photopromoter, was carried out very satisfactorily. Kinetics of hydroxyl radicals reacting between themselves, leading to hydrogen peroxide, other than with substrate or intermediates leading to mineralization, were considered, and it is paralleled by a second competition kinetics involving superoxide radical anion

Nonlinear Modelling of Kinetic Data Obtained from Photocatalytic Mineralisation of 2,4-Dichlorophenol on a Titanium Dioxide Membrane

Photomineralisation of 2,4-dichlorophenol (DCP) in aqueous solutions (10.0–100.0 mg/L of C) was systematically studied at 318±3 K, in an annular laboratory-scale reactor, by photocatalytic membranes immobilizing titanium dioxide, as a function of substrate concentration, and absorbed power per unit length of membrane. Kinetics of both substrate disappearance, to yield intermediates, and total organic carbon (TOC) disappearance, to yield carbon dioxide, were followed (first series of experiments). At a fixed value of irradiance (1.50 W⋅cm−1), other series of mineralization experiments were repeated (second series of experiments) by carrying out only analyses of chemical oxygen demand (COD), in order to compare modelling results of the two sets of experiments. In both sets of experiments, stoichiometric hydrogen peroxide was used as oxygen donor. For the first series of experiments, a kinetic model was employed, already validated in previous work, from which, by a set of differential equations, four final optimised parameters, k1 and K1, k2 and K2, were calculated. By these parameters, the whole kinetic profile could be fitted adequately. The influence of irradiance on k1 and k2 could be rationalised very well by this four-parameter kinetic model. Modelling of quantum yields, as a function of irradiance, could also be carried out satisfactorily. As has been found previously for other kinds of substrates, modelling of quantum yields for DCP mineralization is consistent with kinetics of hydroxyl radicals reacting between themselves, leading to hydrogen peroxide, other than with substrate or intermediates leading finally to carbon dioxide, paralleled by a second competition kinetics involving superoxide radical anion. For the second series of experiments, on the contrary, the Langmuir-Hinshelwood model was employed. Uncertainties of COD analyses, coupled with discrepancies of this model and with its inability to reproduce kinetics up to complete mineralization, are underlined