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Derivatives of isoindolines are a group of nitrogen heterocyclic compounds that are less represented in scientific literature than other heterocyclic compounds containing the nitrogen atom. Natural derivatives of isoindolines were first isolated in the early 1960's and showed various interesting biological activity, e.g. staurosporine indicating antimicrobial, hypotensive, and cytotoxic activity, and acts as thrombocytes aggregation inhibitor and protein kinase inhibitor. Also, there are reports of their application in herbicide and dye industries. Due to these findings, isoindolines received much attention from synthetic organic chemists, and thus new synthetic methods were developed. Most of the methods include phthalaldehyde and corresponding aliphatic and aromatic amines as starting material. Products of these reactions are highly dependent on the reaction conditions, and differently substituted isoindolines are isolated. Synthetic methods starting from other compounds include phthalonitrile, phthalanhydride and phthalaldehyde acid as well as multicomponent reactions. They are also applied as ligands in coordination chemistry, which enables the modelling of three-dimensional structures with desirable areal properties. Derivati izoindolina pokazuju vrlo različita biološka djelovanja in vitro, a neki djeluju i u uvjetima in vivo. Stoga se može očekivati da će istraživanja u budućnosti dovesti i do učinkovitih lijekova za različite vrste bolesti. Pokazuju nesteroidnu protuupalnu aktivnost, antihipertenzivno djelovanje, anksiolitičko, antipsihotičko i antikonvulzivno djelovanje. Djeluju kao lokalni anestetici, vazodilatatori te se vežu na dopaminske i serotononske receptore. Ubrajaju se također u skupinu antidijabetika inhibirajući dipeptidil-peptidaze. Metalni kompleksi izoindolina i njegovih derivata djeluju poput enzima katalaze koji štiti stanice od štetnog djelovanja vodikova peroksida te djeluju i kao inhibitori protein-kinaza. Osim ostalih značajno je njihovo antitumorsko djelovanje na stanice leukemije, karcinoma debelog crijeva, epidermalnog karcinoma te karcinoma jajnika. Oni također inhibiraju enzime koji potiču rast tumorskih stanica kao što su histon deacetilaza te receptori tirozin-kinaze i krvožilnog endotelnog čimbenika rasta (VEGF-R2).

Nekrolog prof. Ivana Esiha, stručnjaka u području korozije i zaštite materijala.

Bone tissue engineering (BTE) is a fast growing field focused on the development of bioactive 3D porous scaffolds as temporary extracellular matrixes that support cell attachment, proliferation and differentiation, and stimulate bone tissue formation in vivo. Over more than ten years, our group has been devoted to developing new biomaterials and methods to prepare 3D porous scaffolds for BTE applications. The potential of natural porous structures such as marine skeletons, composite materials, and hydrogels based on biodegradable polymers and bioresorbable hydroxyapatite ceramics have been studied. In this paper, an overview of our research and main achievements, published in international scientific publications, is provided. This work is licensed under a Creative Commons Attribution 4.0 International License. Inženjerstvo koštanog tkiva brzorastuće je polje istraživanja usmjereno na razvoj bioaktivnih 3D poroznih nosača, kao privremenih izvanstaničnih matrica, koji podržavaju prianjanje, umnažanje i diferencijaciju stanica te potiču stvaranje koštanog tkiva in vivo. Više od deset godina istraživanja naše grupe posvećena su razvoju novih materijala i postupaka za pripravu 3D poroznih nosača za inženjerstvo koštanog tkiva. Kao mogući nosači istraživani su porozni skeleti morskih organizama te kompozitni materijali i hidrogelovi na temelju biorazgradljivih polimera i bioresorbirajuće hidroksiapatitne keramike. U ovom radu dan je prikaz naših istraživanja i glavnih postignuća, objavljenih u međunarodnim znanstvenim publikacijama. Ovo djelo je dano na korištenje pod licencom Creative Commons Imenovanje 4.0 međunarodna.

A new source-based nomenclature system is described which indicates that a particular polymer has been chemically modified. A connective within the name of a polymer, -mod-, is introduced for this purpose as in poly[(A)-mod-(B)]. The system is intended to be used in accordance with source-based naming of polymers but also provides for the use of structure-based names when it is unavoidable. It embraces: (1) modification of a constitutional unit into another, the unique structure of which is known; and (2) a more general modification of a constitutional unit resulting in any one of a number of possible structures. In addition, a new symbol, ∼>, is proposed for use in graphic representations of the structure of modified polymers. Opisan je novi sustav nomenklature (imenovanja) na osnovi podrijetla za polimere koji su kemijski modificirani. U tu je svrhu u ime polimera uvedena poveznica -mod-, npr. poli[(A)-mod-(B)]. Sustav se primjenjuje u skladu s nomenklaturom polimera na osnovi podrijetla, ali predviđa, kada je to neizbježno, i imenovanje polimera na osnovi strukture. Sustav uključuje: (1) modifikaciju konstitucijske jedinice u drugu jedinicu poznate strukture; (2) općenitiju modifikaciju konstitucijske jedinice kojom nastaje bilo koja od više mogućih struktura. Uveden je i novi simbol, ~>, za uporabu pri grafičkom prikazivanju strukture modificiranih polimera.

In this study, open cell 25 % antimony-lead alloy foams are fabricated for possible use to lighten thick plates of lead-acid batteries. A new inexpensive and simple variant of the salt replication process is developed and explored. Different morphology and shapes have been successfully obtained with “excess salt replication” method (abbreviated as ESR method). Best porosity of about 68 % is obtained with salt particles size of about 3 mm. SEM and EDXS investigation of the composite salt/antimony alloy before NaCl leaching revealed the presence of the lead oxides microfilm coating cell walls and becoming lead carbonates after salt removal. Uniaxial compressive behaviour of the resulting cellular materials is studied for foams with porosities between 45 % and 70 %, and salt grain size ranging between 2.5 and 5 mm. A higher plateau stress is reached compared to the results obtained in the literature working on the aluminium foams. The reproducibility of the process is proved along samples. This work is licensed under a Creative Commons Attribution 4.0 International License. U ovom istraživanju izrađene su otvorene ćelije od 25 % antimon-olovnih pjena za moguću primjenu u osvjetljavanju debelih ploča olovno-kiselih baterija. Razvijena je i istražena nova jeftina i jednostavna varijanta procesa repliciranja soli. Različite morfologije i oblici uspješno su dobiveni metodom “prekomjerne replikacije soli” (ESR metodom). Najbolja poroznost od oko 68 % dobivena je pri veličini čestica soli od oko 3 mm. SEM i EDXS ispitivanje kompozitne legure soli/antimona prije ispiranja s NaCl otkrilo je prisutnost mikrofilma olovnih oksida koji oblažu zidove ćelije i nakon uklanjanja soli postaju olovni karbonati. Jednoosno tlačno ponašanje dobivenih materijala ćelije proučava se za pjene s poroznošću između 45 % i 70 % i za veličine zrna soli između 2,5 i 5 mm. Postignuta je veća granica stlačivanja u usporedbi s rezultatima o aluminijskim pjenama dobivenim u literaturi. Ponovljivost postupka dokazana je na uzorcima. Ovo djelo je dano na korištenje pod licencom Creative Commons Imenovanje 4.0 međunarodna.