Ultrazvučna dijagnostika jesetarskih vrsta i korišćenje reproduktivnih ženki na mrestilištu za jesetarske vrste u Azerbejdžanu

Formiranje matičnog stada jesetarskih vrsta za obnavljanje populacija započeto je još 2004. godine u Azerbejdžanu, gde je ostvaren uzgoj riba od stadijuma larvi do adultnih jedinki. Reproduktivne ženke perijske (Kura) jesetre (Acipenser persicus Borodin) koje su uzgajane “od ikre” u uzgojnim sistemima za ribe u Azerbejdžanu su 2013. godine po prvi put korišćene za veštački mrest u uslovima mrestilišta. Cilj ovih studija je bila komparativna evaulacija kvaliteta reproduktivnih ženki koje su uzgajane u uslovima mrestilišta za jesetarske vrste riba i dobijanje njihovog potomstva. Istraživanja su takođe trebala da razviju naučno potkrepljenu dokumentaciju za eksploataciju matičnog stada jesetarskih vrsta, koja bi se bazirala na mrestilišima za jesetarske vrste u Azerbejdžanu. Studija formiranja matičnog stada jesetarskih vrsta “od ikre” u uslovima Khylly ribnjaka za jesetarske vrste u Azerbejdžanu je bila eksperimentalne prirode. Rad na proizvodnji potomstva/mlađi od reproduktivno zrelih ženki je obavljen 2013. godine. Da bi se stimulisalo sazrevanje dve selektivno odabrane ženke persijske (Kura) jesetre iz generacije 2004. uzgajane u mrestilištu, data im je intramuskularno injekcija sa suspenzijom aceton-vodenog ekstrakta hipofize jesetri u odnosu 2.5 mg na 1 kg težine tela. Da bi se izbegao inbriding putem inseminacije ikre, uzeta su dva mužjaka persijske (Kura ) jesetre iz generacije 2005. uzgojene u mrestilištu. Ultrazvučna dijagnostika pola i stepena polne zrelosti, hormonalna stimulacija matičnih riba, fertilizacija i sprečavanje adhezija ikre (odlepljivanje), kao i inkubacija u “Osetr” inkubacionom sistemu je sprovedena u saglasnosti sa postojećim metodama (Dettlaff et al., 1981; Chebanov and Galich, 2010; Mamedov et al., 2009). Analiza uzgoja riba i bioloških indikatora juvenilnih riba koje su čuvane u mrestilištu je pokazala da je razvoj produkovane mlađi korišćenjem reproduktivno zrelih ženki iz matičnog stada bio u saglasnosti sa normama. Jedan deo proizvedene mlađi je zadržan u mrestilištu sa ciljem daljeg istraživanja njihovih morfoloških, bioloških i fizioloških karakteristika. Time su u praksi uzgoja riba u Azerbejdžanu po prvi put korišćene za veštački mrest ženke persijske (Kura) jesetre iz matičnog stada koje je uzgojeno “od ikre” u mrestilištu. Ovi podaci ukazuju na mogućnost dostizanja reproduktivnog stanja različitih jesetarskih vrsta u uslovima mrestilišta. Stvaranje reproduktivnog matičnog stada jesetarskih vrsta u mrestilištima će omogućiti očuvanje genetskog pula jesetarskih vrsta i proširiti mogućnosti za njihov veštački mrest u cilju poriblajvanja otvorenih prirodnih vodenih ekosistema

Iodine catalysis: A green alternative to transition metals in organic chemistry and technology

Iodine and compounds of iodine in higher oxidation states have emerged as versatile and environmentally benign reagents for organic chemistry. One of the most impressive recent achievements in this area has been the discovery of catalytic activity of iodine in numerous oxidative transformations leading to the formation of new Csingle bondO, Csingle bondN, and Csingle bondC bonds in organic compounds. These catalytic transformations in many cases are very similar to the transition metal-catalyzed reactions, but have the advantage of environmental sustainability and efficient utilization of natural resources. Iodine is an environmentally friendly and a relatively inexpensive element, which is currently underutilized in industrial applications. One of the main goals of this review is presenting to industrial researchers the benefits of using catalytic iodine in chemical technology as an environmentally sustainable alternative to transition metals. The present review summarizes catalytic applications of iodine and compounds of iodine in organic synthesis

ATXN2-CAG42 sequesters PABPC1 into insolubility and induces FBXW8 in cerebellum of old ataxic knock-in mice

Spinocerebellar Ataxia Type 2 (SCA2) is caused by expansion of a polyglutamine encoding triplet repeat in the human ATXN2 gene beyond (CAG)31. This is thought to mediate toxic gain-of-function by protein aggregation and to affect RNA processing, resulting in degenerative processes affecting preferentially cerebellar neurons. As a faithful animal model, we generated a knock-in mouse replacing the single CAG of murine Atxn2 with CAG42, a frequent patient genotype. This expansion size was inherited stably. The mice showed phenotypes with reduced weight and later motor incoordination. Although brain Atxn2 mRNA became elevated, soluble ATXN2 protein levels diminished over time, which might explain partial loss-of-function effects. Deficits in soluble ATXN2 protein correlated with the appearance of insoluble ATXN2, a progressive feature in cerebellum possibly reflecting toxic gains-of-function. Since in vitro ATXN2 overexpression was known to reduce levels of its protein interactor PABPC1, we studied expansion effects on PABPC1. In cortex, PABPC1 transcript and soluble and insoluble protein levels were increased. In the more vulnerable cerebellum, the progressive insolubility of PABPC1 was accompanied by decreased soluble protein levels, with PABPC1 mRNA showing no compensatory increase. The sequestration of PABPC1 into insolubility by ATXN2 function gains was validated in human cell culture. To understand consequences on mRNA processing, transcriptome profiles at medium and old age in three different tissues were studied and demonstrated a selective induction of Fbxw8 in the old cerebellum. Fbxw8 is encoded next to the Atxn2 locus and was shown in vitro to decrease the level of expanded insoluble ATXN2 protein. In conclusion, our data support the concept that expanded ATXN2 undergoes progressive insolubility and affects PABPC1 by a toxic gain-of-function mechanism with tissuespecific effects, which may be partially alleviated by the induction of FBXW8

Evaluacija bioloških indikatora mlađi persijske jesetre (acipenser persicus) gajene u ribnjacima sa različitom veštačkom hranom

Cilj ovih istraživanja je bio da se pomoću bioloških i hematoloških parametara, kao i hemijskog sastava tela proceni rast mlađi persijske jesetre gajene u ribnjacima sa različitom veštačkom hranom. Istraživanja su obavljena u toku 2102. godine na mretsilištu za jesetre Khylly, Azerbejdžan. Istraživane su larve i mlađ persijske (Kura) jesetre (Acipenser persicus), gajene u ribnjacima. U 4 bazena ishrana mlađi je obavljena sa veštačkim starterima za jesetre marke TB strane proizvodnje (opcija I), dok je u 4 preostala bazena mlađ hranjena veštačkom hranom proizvedenom na ribnjaku (opcija II). Persijksa jesetra je gajena u ribnjaku u toku 45 dana. Količina proteina, masti, pepela i ugljenih hidrata u telu mlađi jesetre koja je hranjena sa različitom hranom (7 individua) je određivana standardnim metodama. Kao indikatori za određivanje fiziološkog statusa mlađi ribe su korišćeni sadržaj hemoglobina i ukupnih proteina u krvi, kao i sedimentacija eritrocita, broj eritrocita i broj leukocita u 1mm3 krvi. Ranija istraživanja uzgoja u ribnjačkim bazenima su pokazala da je omogućavanje ishrane organizmima imalo pozitivan efekat na celokupno preživljvanje larvi u toku i posle prelaska na egzogenu ishranu. U toku prelaska na egzogenu ishranu broj uginulih larvi u svim varijantama eksperimenta nije prevazilazio 4-6%. I 5-6 dana posle prelaska na egzogenu ishranu broj uginulih larvi je bio mali. Praćenje rasta i preživljavanja larvi persijske jesetre u bazenima su pokazala da je korišćenje naupliusa A. salina kao polazne ishrane žive hrane u prvim fazama ishrane veoma povoljno za rast jesetri u bazenima. Mlađ riba koje su hranjene sa veštačkom hranom stranog proizvođača (opcija I) je pokazivala relativno bolji rast, kao i bolje biološke i hematološke parametre, što je, po našem mišljenju rezultat povoljnijeg hemijskog sastava i sadržaja ove hrane. Analize hemijskog sastava tela persijskih jesetri u čijoj su ishrani korišćene različite hrane takođe pokazuju da kvalitet gajene mlađi riba zavisi od kvalteta korišćene hrane. Uslovi skladištenja, ishrana i koeficijent ishrane takođe imaju veliki uticaj na kvalitet, kao i na vrednosti parametara krvi i hemoglobina kod mlađi riba. Pozitivna strana uzgoja u ribnjačkim bazenima leži u tome da mlađ ribe raste u potpuno kontrolisanim uslovima i željeni rast eksperimentalnih riba u gustim nasadima i kratkom vremenskom roku može da se ostvari tačnim pridržavanjem pravila za optimalni biotehnološki rast jesetri korišćenjem efektivnih i visoko dostupnih po veličini organizama za ishranu (Mamedov et al., 2009). U tom slučaju, kvalitet mlađi ribe u uzgoju i njen fiziološki status zavise od uslova skladištenja i kvaliteta korišćene hrane

Ring Opening Metathesis Polymerization

In recent years, the olefins metathesis has established itself as a powerful tool for carbon-carbon bonds forming and has found numerous applications in polymer chemistry. One of the important directions of metathesis is the polymerization with cycle opening. A study of new ruthenium catalysts, resistant to the many functional groups effects, has showed the possibility of synthesizing functionalized polymers with unique properties. In this chapter, reactivity and activation parameters of eight different norbornene dicarboxylic acid alkyl esters in the presence of a Hoveyda-Grubbs II catalyst for the ring opening metathesis polymerization were determined by 1H NMR analysis in-situ. The molecules of esters differ in the aliphatic radical structure and the location of the substituent groups. Kinetic studies have shown that effective polymerization constants and activation parameters strongly depend on the monomer structure. It is shown that the elongation of the aliphatic radical does not significantly affect the reactivity, but significantly changes the activation parameters. The branching of the aliphatic radical significantly affects both the reactivity of the corresponding ester and the activation parameters of the polymerization. The position of the substituents in the norbornene ring of the ester also has a significant effect on the activation parameters of metathesis polymerization

Facile one-pot synthesis of diaryliodonium salts from arenes and aryl iodides with oxone

A straightforward synthesis of diaryliodonium salts is achieved by using Oxone as the stoichiometric oxidant. Slow addition is the key to obtaining good yields and purities of the reaction products, which are highly useful reagents in many different areas of organic synthesis

Iodine monoacetate for efficient oxyiodinations of alkenes and alkynes

A novel and inexpensive, environmentally friendly method for the preparation of iodine monoacetate is presented using iodine and Oxone in acetic acid/acetic anhydride. The reagent is used in a highly efficient approach for the regio- and diastereoselective iodo­acetoxylation of alkenes and alkynes in a simple one-pot process

Synthesis of polydicyclopentadiene using the Cp2TiCl2/Et2AlCl catalytic system and thin-layer oxidation of the polymer in air

The polymerization process of dicyclopentadiene using a multicomponent catalytic system based on bis(cyclopentadienyl)titanium dichloride and diethylaluminum chloride was studied. It was demonstrated that the application of an excess of the aluminum component leads to the formation of stable charged complexes of blue discoloration, which initiate cationic polymerization of dicyclopentadiene. Unstabilized thin layers of obtained polydicyclopentadiene undergo oxidation and structuring under atmospheric oxygen. Oxidation of polydicyclopentadiene films in air occurs slowly during several weeks and can be determined by the increase of carbonyl and hydroxyl adsorption bands in infrared spectra. Along with oxidation, cross-linking processes occur in polymers, which lead to a change in physical parameters of the layers, and more precisely to a decrease in the permeability of atmospheric oxygen through the layers. Consequently, this leads to the transition of the oxidation from a kinetic mode into a diffusive mode. Such structural changes do not occur in a polymer that was stabilized by adding an antioxidant

Facile One-Pot Synthesis of Diaryliodonium Salts from Arenes and Aryl Iodides with Oxone

A straightforward synthesis of diaryliodonium salts is achieved by using Oxone as the stoichiometric oxidant. Slow addition is the key to obtaining good yields and purities of the reaction products, which are highly useful reagents in many different areas of organic synthesis

Preparation and X-ray structure of 2-iodoxybenzenesulfonic acid (IBS) - a powerful hypervalent iodine(V) oxidant

The selective preparation of 2-iodoxybenzenesulfonic acid (IBS, as potassium or sodium salts) by oxidation of sodium 2-iodobenzenesulfonate with Oxone or sodium periodate in water is reported. The single crystal X-ray diffraction analysis reveals a complex polymeric structure consisting of three units of IBS as potassium salt and one unit of 2-iodoxybenzenesulfonic acid linked together by relatively strong I=O···I intermolecular interactions. Furthermore, a new method for the preparation of the reduced form of IBS, 2-iodosylbenzenesulfonic acid, by using periodic acid as an oxidant, has been developed. It has been demonstrated that the oxidation of free 2-iodobenzenesulfonic acid under acidic conditions affords an iodine(III) heterocycle (2-iodosylbenzenesulfonic acid), while the oxidation of sodium 2-iodobenzenesulfonate in neutral aqueous solution gives the iodine(V) products