Alterations of FHIT and P53 genes in keratocystic odontogenic tumor, dentigerous and radicular cyst

BACKGROUND: The purpose of this study was to determine fragile histidine triad (FHIT) and p53 protein expression, and to analyze FHIT and p53 gene status in keratocystic odontogenic tumor (KOT), dentigerous cysts (DC) and radicular cysts (RC). ----- METHODS: The methods used were immunohistochemistry and molecular genetic methods including loss of heterozygosity (LOH) and gene sequencing. ----- RESULTS: FHIT protein expression was different among groups. Aberrant expression was the highest in KOT, then in RC and DC. p53 protein expression was different among groups. LOH in paraffin-embedded specimens was detected in 22.6% and 12.9% for FHIT and p53 respectively. Mutation of p53 gene at codon 237 was observed in only two specimens (one KOT and one DC). Of the six frozen specimens, three exhibited FHIT gene LOH (two RC and one KOT). KOT showed loss of exons 6-7 at FHIT locus and mutation at codon 237 at p53 locus, but this could be a chance result. ----- CONCLUSION: Aberrations of FHIT and p53 genes/proteins could be considered markers responsible for the development of odontogenic lesions

Insulinu slični čimbenici rasta/receptori kod raka pluća

Perturbation in a level of any peptide from insulin-like growth factor (IGF) family (ligands, receptors, binding proteins) seems to be implicated in lung cancer formation; IGF ligands and IGF-R1 through their mitogenic and antiapoptotic action, and the IGF-R2/M-6-P possibly as a tumor suppressor. In this respect we have found that human lung cancers overproduce IGF-1, IGF-2 and IGF-R1, which in turn stimulates their proliferation by autocrine mechanism, decrease apoptosis rate and increase telomerase activity. At the same time majority of tumors underproduce IGF-R2 possibly due to the mutations in both alleles of this gene. However, cancer cell proliferation can be abrogated or alleviated by blocking the mRNA activity of IGF-1, IGF-2 and/or IGF-R1 genes indicating that the use of monoclonal antibodies or an anti-sense approach may represent an effective and practical cancer gene therapy strategy.Velike promjene vrijednosti bilo kojeg peptida iz porodice insulinu sličnih čimbenika rasta /IGF/ (ligandi, receptori, vezujući proteini) čini se imaju utjecaja na nastanak raka pluća; IGF ligandi i IGF-R1 svojim mitogeničnim i anti-apopstotskim djelovanjem, a IGF-R2/M-6-P vjerojatno kao tumorski supresor. U tom pogledu otkrili smo da rak pluća u ljudi proizvodi previše IGF-1, IGF-2 i IGF-R1, čime se pak potiče njihovo širenje pomoću autokirnog mehanizma, smanjuje brzina apoptotskog procesa i povećava aktivnost telomeraze. Istodobno većina tumora proizvodi premalo IGF-R2, vjerojatno zbog mutacija prisutnih u oba alela toga gena. Me|utim, širenje stanica raka moguće je prekinuti ili usporiti blokadom aktivnosti mRNA gena IGF-1, IGF-2 i/ili IGF-R1, što upućuje na to da bi primjena monoklonskih protutijela ili tzv. antisense pristupa mogla biti učinkovita strategija upotrebljiva u genskoj terapiji raka

Contemporary approaches to teaching EFL grammar in Croatia

This study deals with the issues related to English grammar. The purpose of this study was to provide an insight into the current situation of teaching EFL grammar in Croatia and describe possible new trends reflected in the approach that is present in Croatian schools. More precisely, this study investigates the types of presentation and practice of grammatical structures that are available to Croatian teachers and learners in English textbooks. It is based on a qualitative study of grammar-based textbooks used in the majority of high schools in Croatia. The textbooks used for the study are New Headway Intermediate the second edition published in 1996 and New Headway Intermediate the fourth edition published in 2009. In order to collect the necessary data, we formed 6 research questions. The first two referred to the type of presentation in order to determine if there is a balance between inductive, deductive and focus-on-form presentation and if the presentation provides contextualized and authentic examples of grammatical structures. The rest of the questions referred to the types of practice in order to determine if the textbooks provide practice that fosters development of all four skills and balances accuracy and fluency so learners can acquire grammar structures and the ability to use that knowledge for communicative purposes. The analysis has shown that both editions foster contextualized presentation and practice and development of all four skills. However, the fourth edition published in 2009 shows higher percentage of balance of different types of introduction, especially focus on form. There is also a higher percentage of balance of individual, pair and group work and balance between accuracy and fluency. The results show that editions differ in the way they present grammar. The second edition deals with grammar in a way that is more isolated when compared to presentation and practice in the fourth edition. Furthermore, the fourth edition reflects the latest ideas suggested by researchers and CEFR by focusing on form within communicative contexts. This shows that the textbook used by the majority of Croatian high schools keeps up with the changes in the field of teaching foreign languages and fosters an eclectic approach that balances different modes of teaching EFL grammar. This means that a high percentage of both teachers and learners have the opportunity to teach and learn according to their personal styles and strategies

The Clinical Use of Fiber- Reinforced Composite

Uporaba vlaknima ojačanih kompozita dobila je na važnosti tek posljednjih nekoliko godina, premda se o njezinoj vrijednosti u stručnim stomatološkim radovima pisalo već u ranim šezdesetim godinama prošloga stoljeća. Vlaknima ojačani kompoziti mogu se razvrstati prema vrsti vlakana, njihovu smjeru, te prema obradi organskom smolom. Polietilenska, staklena, kevlar i ugljična vlakna mogu biti u obliku pojedinačnih ravnih valkana ili u pletenom obliku. Čimbenici o kojima ovisi čvrstoća vlaknima ojačanih kompozita jesu smjer vlakana, množina vlakana, obloženost vlakana organskom smolom, svezivanje vlakana s organskom smolom, te sama svojstva valkana i organske smole. U restaurativnoj stomatologiji upotrebljavaju se vlakna s jednostrukom, dvostrukom i višestrukom usmjerenošću. Vlakna imaju ulogu učvrsne osnove samo u onim slučajevima u kojima se sila opterećenja prenosi s kompozitne osnove na vlakna. U slučaju nastanka pukotina i stvaranja praznoga prostora između vlakana i kompozitne osnove, smanjuje se sposobnost primanja opterećenja. Nedostatna obloženost vlakana organskom smolom uzrokuje probleme povećanoga zadržavanja vode. To slabi mehanička svojstva i/ili stvara nakupine kisika što inhibira radikalnu polimerizaciju organske smole, a time i nastanak ostatnoga monomera od čega može nastati upalna reakcija na sluznici usne šupljine. Novi vlaknima ojačani kompoziti mogli bi biti sredstvo izbora za izradbu udlaga, bezmetalnih i nekeramičkih nadomjestaka s izvrsnom estetikom i dugotrajnošću nadomjestka.Fiber reinforcement has been discussed in the dental literature since the early 1960s, althogh the more recent availability of commercial products is only now leading to recognition and general clinical use. Fiber-reinforced composite can be described by fiber type and fiber orientation, in addition to the presence or abscence of preimpregantion with a resin. Polyethylene, glass, kevlar and carbon fibers have all been used in either unidirectional or woven fiber orientations. The factors affecting the strength of fiber-reinforced composite are orientation of fibers, quantity of fibers, impregnation of fibers with the matrix polymer, adhesion of fiber to the matrix polymer, properties of fibers vs. properties of matrix polymer.In dental reconstructions, undirectional and bi- or multidirectional fiber orientation is used. Fiber reinforcement is only successful is the loading force can be transferred from the matrix to the fiber. In the case of voids between the matrix and the fiber, the load-bearing capacity of fiberreinforced composite decreases. Poorly impregnated fibers cause another proble: increase in water absorbtion, which reduces the mechanical properties, and oxygen reserves, which inhibits radical polymerization of the polymer matrix and increases the residual monomer content which can lead to irritant reactions in the oral mucosa. A new fiber-reinforced composite provides the potential for fabrication of splints, metal-free, ceramic-free prosthesis with potential for long-term durability and excellent esthetics

Lower Miocene Alluvial Deposits of the Pozeska Mt. (Pannonian Basin, Northern Croatia): Cycles, Megacycles and Tectonic Implications

In the area of the present Pozeska Mt. braided alluvial fans were formed during the Early Miocene above the subsiding Cretaceous-Palaeogene basement. Due to autocyclic processes, i.e. lateral migration of flows due to vertical aggradation of longitudinal bars, or migration of the main trench, small-scale fining-upward cycles were formed. The complete succession of the alluvial deposits is composed of two fining-upward megacycles, which are the consequence of allocyclic influences, i.e. the pulsating character of synsedimentary tectonics. Megacycles were developed parallel to backstepping of the front of the fault scarp towards the mountain massif, caused by normal faulting along the active margin of an extensional basin. This kind of depositional style indicates that the Sava fault operated as a normal fault at the beginning of its life during the Early Miocene, probably the Ottnangian