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This study presents detailed foraminiferal, ostracod, and calcareous nannofossil analyses of five Middle Miocene sections located in the Central Paratethyan realm, namely in Poland, Romania and the Republic of Moldova. Based on foraminiferal distribution, five biostratigraphically important assemblages (labelled A-E) are distinguished. Foraminifera data combined with ostracoda and nannofossil evidence allowed correlation between the studied sections, and a comparison with the deposits of similar age from the Transylvanian, Vienna and Pannonian basins, as well as with the Transcarpathian regions. The micropaleontological record across the Badenian-Sarmatian boundary interval is also presented.

Three enzymes were immobilized onto polyionic hydrogel, ChitoXan, obtained by complexation between chitosan and xanthan. The biocatalysts used were two proteases (protease type XIX from Fungal d'Aspergillus sojae and the trypsin type II.S from Porcine Pancreas) and a lipase (lipase Type VII from Candida rugosa). The immobilization efficiencies and the relative activities were investigated for these enzymes. The immobilization efficiencies changed with each enzyme and varied between 53 and 80%. Good relative activities were found for the lipase Type VII from Candida rugosa and the protease type XIX from Fungal d'Aspergillus sojae. For the latter, the influenced of serveral factors were studied: molarity of the storage buffer, storage temperature and time of hydrogel, and the enzyme concentration. For the immobilized lipase, hydrolysis of olive oil in aqueous and organic media has been compared. This study confirmed that the lipase modified the external and internal structure of the hydrogel from fibrillar to the formation of globular structures in the presence of lipases. [ABSTRACT FROM AUTHOR]

Poly(methylmethacrylate-b-styrene) and poly(methylmetha-crylate-b-acrylonitrile) block copolymers are synthesized by means of the 4,4′-azo-bis-(4-cynovaleryl)-benzoyldiperoxide. In the first stage a polymethylme-thacrylate prepolymer is synthesized using the above mentioned initiator.The prepolymer containing peroxide end groups is employed in the second stage for the block copolymerization of styrene or acrylonitrile.The block copolymer structure was elucidated by means of IR and NMR spectral measurements. [ABSTRACT FROM AUTHOR]

A method for the preparation of hydrogels from the complexation of chitosan and xanthan is reported. Stable hydrogels capable of retaining be tween 65 and 95% weight water were prepared. The water retention and prop erties of the hydrogels were studied as a function of the degree of acetylation of chitosan and the ratio chitosan/xanthan used in the preparation of the gel. Spectroscopic FTIR was used to confirm complexation between the amine (chi tosan) and carboxylic (xanthan) groups. Electron micrographs (SEM and TEM) show the formation of a fibrillar structure with characteristic pore sizes be tween 100 and 1000 nm and fibril diameters between 50 and 100 nm. The diffu sion coefficient of 4-O-methyl-d-glucurono-D-xylan Remazol Brilliant Blue R (RBB-xylan) in the complex chitosan-xanthan was 2.02 × 10-12 m 2s-1 at 30°C. The chitosan-xanthan complex was used to immobilize two enzymes (endo-1,4- β-xylanase and protease) either as single enzymes or as a binary system. Immo bilization varied between 85 and 98%. The immobilized xylanase activity was significantly greater with respect to the free enzyme while the binary enzyme system promoted protease activity. [ABSTRACT FROM PUBLISHER]

Descoperirea genei methyl-CpG binding protein 2 (MECP2) situate pe cromozomul Xq28 ca fiind implicata in producerea Sindromului Rett (RTT) a fost urmata de asocierea unui spectru de fenotipuri cu mutatiile acestei gene. Distributia mutatiilor MECP2 a fost studiata in diverse populatii, doar recent acest studiu fiind ini- tiat in Romania. Am initiat primul studiu localizat pentru identificarea mutatiilor genei MECP2 utilizand PCR si secventiere Sanger. Am investigat 9 paciente, din zona de vest a tarii, 7 prezentand forma clasica de RTT si 2 prezentand forme atipice, provenite. Screeningul mutatiilor a relevat 3 mutatii diferite, prezente la 4 paciente si 5 variatii genetice nonpatogenice. Una dintre mutatiile detectate, deletia unei nucleotide in pozitia 225 (c.225delG) nu a mai fost descrisa anterior. Rata de detectie a mutatiilor in studiul nostru a fost de 44%. In aceast studiu ne-am centrat pe o abordare practica necesara geneticianului molecular in cadrul procesului de screening al mutatiilor genei MECP2 la pacientii cu RTT. Dezideratul nostru este de a extinde protocolul de screening al mutatiilor MECP2 la cazurile de tulburari asociate genei MECP2, de a oferi diagnostic prenatal, si de a-l completa cu alte tehnici care pot detecta rearanjamente ale genei MECP2.