Encapsulated pyridazine Cr(III) complexes prepared from biosorbents supported in zeolites

The encapsulation of a pyridazine Cr(III) complex was prepared from a robust biosorption system consisting of a bacterial biofilm supported on NaY or NaX zeolites. The maximum removal efficiency was 20% for Cr in both systems based in NaY or NaX. The bacterial biofilm, Arthrobacter viscosus, supported on the zeolite reduce Cr(VI) to Cr(III). The Cr(III) is retained in the zeolite by ion exchange. These occluded complexes were characterized by chemical analysis, spectroscopic methods (FTIR and UV/Vis) and surface analysis (DRX). The various techniques of characterization used show that the Cr(III) complex was effectively encapsulated in the zeolite and this process does not modified the morphology and structure of the NaY/NaX zeolites. These materials have potential applications in heterogeneous catalysis in mild conditions.Departamento de Ciências da Terra of Universidade do Minho; Fundação para a Ciência e a Tecnologia (FCT

Hematološki profil farmski uzgajanog Sorubim lima: referentne vrijednosti, stanična morfologija i citokemija.

Hematology implies rapid and practical analysis to assist the diagnosis of fish homeostatic imbalance. This study determined the blood reference intervals in an important native South American catfish farmed in the Brazilian Pantanal wetland, Sorubim lima (Siluriformes, Pimelodidae), and describes the morphological and cytochemical characteristics of the cells. A total of 92 fish reared in a fish farm were examined for reference intervals 25 - 75% of total plasmatic protein, hemoglobin, red blood cell count (RBC), hematocrit, mean corpuscular volume (MCV), mean corpuscular hemoglobin concentration (MCHC) and total thrombocyte and leukocyte count (WBC). Periodic acid Schiff (PAS) with salivary amylase, bromophenol blue, Sudan black B and toluidine blue (metacromasy) were the cytochemical stains employed to signal glycogen, proteins, lipids and nuclei in thrombocytes and leucocytes. In the blood smears, monocytes, lymphocytes, neutrophils, basophils, eosinophils, PAS - positive granular lymphocytes (LG-PAS) and thrombocytes were observed. Siluriforme similar results were observed in neutrophils and eosinophils morphology. Compared to other pimelodidae RBC, hematocrit and MCV showed the lowest index variation. In contrast to other siluriformes fish, S. lima showed the concomitant presence of circulating eosinophils and basophils.Hematologija podrazumijeva brze i praktične analize koje pomažu dijagnostici poremećene homeostatske ravnoteže u riba. Ovim istraživanjem utvrđeni su referentne vrijednosti morfoloških i citokemijskih obilježja krvnih stanica južnoameričkog soma Sorubim lima (Siluriformes, Pimelodidae), uzgajanog u močvarnim područjima Brazila. Kod ukupno 92 farmski uzgojene ribe istraženi su referentne vrijednosti za ukupne bjelačevine plazme, hemoglobin, broj eritrocita, hematokrit, srednji volumen eritrocita, prosječnu koncentraciju hemoglobina te ukupni broj trombocita i leukocita. Za citokemijsko određivanje glikogena, bjelančevina, masti te jezgri u trombocitima i leukocitima upotrijebljen je Schiffov perjodni reagens (PAS) s amilazom sline, bromfenolnim plavilom, sudanskim crnilom B i toluidinskim plavilom (metakromatska zrnca). U krvnim razmascima utvrđeni su monociti, limfociti, neutrofili, bazofili, eozinofili, PAS pozitivni granulirani limfociti i trombociti. Ustanovljeno je da je morfologija neutrofila slična onoj u riba somovki (Siluriformes). U usporedbi s ostalim dugobrkim ribama (Pimelodidae), broj eritrocita, hematokrit i srednji volumen eritrocita pokazali su najniži indeks varijacija. Za razliku od ostalih somovki, S. lima je pokazala istodobnu prisutnost cirkulirajućih eozinofila i bazofila

Pyridazine chromium complexes in NaY zeolite

The immobilization of transition metal complexes with redox catalytic activity in solid supports has attracted much interest due to their potential use as hete rogeneous catalysts in mild conditions. One of the most common strategies for the preparation of zeolites with metal transition complexes is the flexible ligand method. The incorporation of the cation requires the exchange with the charge-balancing cation from zeolite framework. Two different procedures for ion exchange are: the traditional ion exchange from aqueous solutions containing the metal and metal biosorption by microorganisms supported on the zeolite. In previous work, we reported the development of a biosorption system for Cr(IV) removal from industrial wastewater, by using bacterial biofilm supported on zeolites. The system has shown ability to remove chromium from aqueous solutions with concentrations ranging 10 – 250 mg/L. The biological activity of the employed bacteria, Arthrobacter viscosus, induces reduction of the Cr (VI) to Cr (III) species. The aim of this work is to evaluate the traditional ion exchange and the biosorption paths for the immobilization of chromium complexes in NaY zeolite. The bio-monomer under investigation, the 3-methoxy-6-chloropyridazine, is a bi-dentate ligand and can offer only nitrogen atoms as donors (Scheme 1). Complexes of chromium with pyridazine have the potential to act as catalysts for oxidation of phenols in mild conditions. The pyridazine derivative ligand and the new materials were characterized by chemical analysis, spectroscopic methods (NMR, FTIR and UV/Vis), XRD and thermal analysis (TGA). The data obtained from various techniques of characterization are compatible with the fact that the chromium complexes were effectively immobilized in NaY zeolite by two different procedures. The data indicate that all complexes achieved by both procedures are Cr(III) pyridazine derivative complexes inside the NaY structure

Oxidation of cyclohexanol and cyclohexene with triazenido complexes of chromium immobilized in biosorption FAU supports

This work presents the recovery of biosorption supports as an alternative source of benign production of heterogeneous catalysts for oxidation reactions in mild conditions. Cr-containing FAU zeolite, in sodium form (NaY) and in proton form (HY), was recovered from biosorption studies and reused as support for the preparation of heterogeneous catalysts by the flexible ligand method, using 1,3-diphenyltriazene derivatives. Results showed that the ligand play an important role in the coordination of Cr inside the zeolite. The catalysts showed good activity for the oxidation of cyclohexanol, reaching a maximum of 63.5% conversion. Cr leaching was evaluated and it was found that the Cr-FAU supports lost some of the Cr into the reaction medium, whereas immobilization of Cr-complexes reduced the referred leaching. For the cyclohexene oxidation, a maximum 72.9% conversion was achieved with a HY zeolite-based catalyst.H. Figueiredo and B. Silva are thankful to the "FCT - Fundacao para a Ciencia e Tecnologia" for their respective research grants. IKB thanks FO' for the contract under the program Ciencia 2007. This work was partially funded by the Centre of Biological Engineering and the Centre of Chemistry (University of Minho, Portugal) through FCT strategic projects PEst-OE/EQB/LA0023/ 2013 and PEst-C/QUI/UI0686/2011 (nF-COMP-01-0124-FEDER022716), the Project "BioEnv - Biotechnology and Bioengineering for a sustainable world", REF. NORTE-07-0124-FEDER-000048, co-funded by the Programa Operacional Regional do Norte (ON.2 - 0 Novo Norte), QREN and FEDER, and by the Spanish Ministry of Science and Innovation (CTQ2008-04261/PPQ)

Immobilization of chromium complexes in zeolite Y obtained from biosorbents : synthesis, characterization and catalytic behaviour

The goal of this study is the preparation of new heterogeneous catalytic materials to be used in oxidation reactions under mild conditions through the valuation of heavy metals in wastewater. The samples used in the immobilization of chromium complexes were prepared from a dichromate solution of 100 mgCr L−1. The zeolite CrNaY was prepared from a robust biosorption system consisting of a bacterial biofilm, Arthrobacter viscosus, supported on zeolite NaY. The biofilm performs the reduction of Cr(VI) to Cr(III) and this cation is retained in the zeolite by ion exchange. The immobilization of chromium complexes with heterocyclic ligands in the supercages of Y zeolite was performed by the in situ synthesis with three different ligands, 3-methoxy-6-chloropyridazine (A), 3-piperidino-6-chloropyridazine (B) and 1-(2-pyridylazo)-2-naphthol (C). A sample loaded with Cr from a liquid solution with the same initial concentration was prepared as a reference through the traditional direct ion-exchange method and coordinated with ligand (A). The resulting catalysts were fully characterized by different techniques (FTIR, XRD, TGA, SEM, Raman, cyclic voltammetric studies and chemical analysis) and the results confirmed that the Cr complexes were immobilized in supercages of NaY. Catalytic studies were performed in liquid phase for the cyclohexene oxidation, at 40 °C, using tert-butyl hydroperoxide (TBHP) as the oxidizing agent. All the prepared catalysts exhibited catalytic activity for the oxidation reaction.União Europeia. Fundo Europeu de Desenvolvimento Regional (FEDER)Fundação para a Ciência e a Tecnologia (FCT) - ref. POCTI/44449/CTA/2002, POCTI-SFA-3-68

The Portuguese Society of Rheumatology position paper on the use of biosimilars

Biotechnological drugs have become a fundamental resource for the treatment of rheumatic patients. Patent expiry of some of these drugs created the opportunity for biopharmaceutical manufacturers to develop biosimilar drugs intended to be as efficacious as the originator product but with a lower cost to healthcare systems. Due to the complex manufacturing process and highly intricate structure of biologicals, a biosimilar can never be an exact copy of its reference product. Consequently, regulatory authorities issued strict preclinical and clinical guidelines to ensure safety and efficacy equivalence and, in September 2013, the biosimilar of infliximab was the first biosimilar monoclonal antibody to be authorized for use in the European Union. The current document is a position statement of the "Sociedade Portuguesa de Reumatologia" (Portuguese Society of Rheumatology) on the use of biosimilar drugs in rheumatic diseases. Two systematic literature reviews were performed, one concerning clinical trials and the other one concerning international position papers on biosimilars. The results were presented and discussed in a national meeting and a final position document was discussed, written and approved by Portuguese rheumatologists. Briefly, this position statement is contrary to automatic substitution of the originator by the biosimilar, defends either a different INN or the prescription by brand name, supports that switching between biosimilars and the originator molecule should be done after at least 6 months of treatment and based on the attending physician decision and after adequate patient information, recommends the registration of all biosimilar treated patients in Reuma.pt for efficacy, safety and immunogenicity surveillance, following the strategy already ongoing for originators, and opposes to extrapolation of indications approved to the originator to completely different diseases and/or age groups without adequate pre-clinical, safety or efficacy data.info:eu-repo/semantics/publishedVersio

Erratum to: The study of cardiovascular risk in adolescents – ERICA: rationale, design and sample characteristics of a national survey examining cardiovascular risk factor profile in Brazilian adolescents

1585