OPA1 processing controls mitochondrial fusion and is regulated by mRNA splicing, membrane potential, and Yme1L

OPA1, a dynamin-related guanosine triphosphatase mutated in dominant optic atrophy, is required for the fusion of mitochondria. Proteolytic cleavage by the mitochondrial processing peptidase generates long isoforms from eight messenger RNA (mRNA) splice forms, whereas further cleavages at protease sites S1 and S2 generate short forms. Using OPA1-null cells, we developed a cellular system to study how individual OPA1 splice forms function in mitochondrial fusion. Only mRNA splice forms that generate a long isoform in addition to one or more short isoforms support substantial mitochondrial fusion activity. On their own, long and short OPA1 isoforms have little activity, but, when coexpressed, they functionally complement each other. Loss of mitochondrial membrane potential destabilizes the long isoforms and enhances the cleavage of OPA1 at S1 but not S2. Cleavage at S2 is regulated by the i-AAA protease Yme1L. Our results suggest that mammalian cells have multiple pathways to control mitochondrial fusion through regulation of the spectrum of OPA1 isoforms

Can multiple fish farms be integrated within a semi-enclosed bay without causing acute ecosystem degradation?

The current study explores the possibility that multiple fish farms (FFs) containing sea bass (Dicentrarchus labrax) and sea bream (Sparus aurata) can be successfuly integrated within a semi enclosed bay in the Croatian Adriatic. The research focuses on determining principal environmental factors (EFs) that control the integration and atempts to estimate their individual and synergic ability to influence deposition and removal of organic matter (OM) and trace elements (TE) from the system. The complexity of the designated tasks demanded a comprehensive number of various datasets and samples to be used in the analysis. The ADCP data revealed strong wind induced currents forming within the research domain resulting in high system flushing efficiency (3.5 – 6 days). The sediment samples from all stations contained relatively inert minerals which contributed to overall low OM and TE concentrations and very limited variability found across the entire bathymetric range. The thermal advection effect recorded at two stations was attributed to specific seabed topography and the hydrodynamic response formed during Maestral wind episodes. The results indicate that a successful integration of four FFs has taken place within the research site (semi enclosed bay), and that the key EFs responsible for its success are strong wind induced hydrodynamics, favorable seabed topography and sediment mineral composition. The synergy of the principal EFs that formed within the system was found to have an attenuating effect regarding FFs chemical influence (OM and TE) and an amplifying one regarding spatial footprint which extended to ≈ 2000 m distance

Comparative Investigation of the Fracture Strengths of Crowns of Three Different Non-metal Materials

Zahtjevi pacijenata za visokom estetikom tijekom rekonstruktivnih protetskih zahvata pospješili su razvoj novih materijala i tehnologija. Sile koje djeluju u postkaninom dijelu zubnoga niza iznose ≥ 500 N, pa i materijali koji se upotrebljavaju za izradbu nadomjestaka moraju izdržavati te sile. Svrha je istraživanja bila istražiti otpornost na lom triju nekovinskih materijala: 1. ceromer (Targis, Ivoclar-Vivadent), 2. ceromer ojačan vlaknasto ojačanim kompozitom (Targis/Vectris, Ivoclar-Vivadent), 3. nekovinski keramički sustav (IPS Empress 2, Ivoclar-Vivadent). Iz svake vrste materijala izrađeno je po 18 istovjetnih krunica na gipsanome modelu izbrušenog prirodnog drugoga donjeg pretkutnjaka, prema uputama proizvođača. Isti je brušeni zub upotrijebljen za izradbu kovinskoga modela na kojemu su umetane krunice u univerzalnu kidalicu ZWICK. Tlačna je ploča modificirana s trnom dijametra 7 mm koji je djelovao silom na okluzijsku plohu pod kutom od 180°. Sila je aplicirana do prvoga znaka loma, a iznos je zabilježen. Polovina je uzoraka prije ispitivanja termociklirana 1000 puta po 20 sekunda na temperaturi od 2°C i 55°C s razmakom od 40 sekunda između urona za temperiranje uzoraka. Izmjerena srednja vrijednost iznosa sile do loma za netermociklirane uzorke iznosile su za krunice iz ceromera 577,8 ± 113,4 N, za krunice iz ceromera i vlaknasto ojačanoga kompozita 923,3 ± 229 N, a za krunice iz nekovinske keramike 1208,9 ± 161,8 N. Mann-Whitney U testom utvrđena je znatna razlika između svih triju materijala (p<0,05) u iznosima opterećenja do loma uzorka. Termocikliranje nije znatno smanjilo iznos sile do loma uzorka. Istraživanjem je utvrđeno da su sva tri materijala pogodna za izradbu trajnih nadomjestaka u području žvačnoga središta, jer svi mogu izdržati silu veću od 500 N.The demands of patients for high aesthetics during reconstructive prosthetic procedures accelerated the development of new materials and technology. Forces acting in the post-canine part of the dental arch amount to ≥ 500 N, and thus the material used for fabrication of the restoration must withstand such forces. The aim of this investigation was to study the resistance to fracture of three non-metal materials: 1. ceromer (Targis, Ivoclar-Vivadent), 2. ceromer reinforced with fibre reinforced composite (Targis/Vectris, Ivoclar-Vivadent), and 3. non-metal ceramic system (IPS Empress 2, Ivoclar-Vivadent). Eighteen identical crowns were fabricated from each type of material on a plaster model of a polished natural second lower premolar, according to the manufacturer’s instructions. The same tooth was used for fabrication of a metal model on which crowns were placed in the universal testing device ZWICK. The compressive plate was modified with a pin 7mm in diameter, which acted with force on the occlusal surface at an angle of 180˚. Force was applied up to the first sign of fracture, and the amount recorded. Half of the samples prior to the examination were thermocycled 1000x for 20 seconds at temperatures of 2˚C and 55˚C with 40 second intervals between immersion of the tempered sample. The mean value measured of the amount of force up to fracture for non-thermocycled samples amounted to 577.8 +/- 113.4 N for crowns of ceromer, 923.3+/- 229 N for crowns of ceromer and fibre reinforced composite, and 1208.9 +/- 161.8 N. for crowns of non-metal ceramic. Significant difference was determined by Mann-Whitney U test between all three materials (p < 0.05) for the amounts of loading up to fracture of the samples. Thermocycling did not significantly reduce the amount of force up to fracture of the sample. The investigation determined that all three materials are satisfactory for fabrication of permanent restorations in the area of the masticatory centre, as all withstand force greater than 500 N

Endoplasmic reticulum stress is involved in response of human laryngeal carcinoma cells to carboplatin but is absent in carboplatin resistant cells

The major obstacle of successful tumor treatment with carboplatin (CBP) is the development of drug resistance. In the present study, we found that following treatment with CBP the amount of platinum which enters the human laryngeal carcinoma (HEp2)-derived CBP-resistant (7T) cells is reduced relative to the parental HEp2. As a consequence, the formation of reactive oxidative species (ROS) is reduced, the induction of endoplasmic reticulum (ER) stress is diminished, the amount of inter- and intrastrand cross-links is lower, and the induction of apoptosis is depressed. In HEp2 cells, ROS scavenger tempol, inhibitor of ER stress salubrinal, as well as gene silencing of ER stress marker CCAAT/enhancer-binding protein (CHOP) increases their survival and renders them as resistant to CBP as 7T cell subline but did not influence the survival of 7T cells. Our results suggest that in HEp2 cells CBP-induced ROS is a stimulus for ER stress. To the contrary, despite the ability of CBP to induce formation of ROS and activate ER stress in 7T cells, the cell death mechanism in 7T cells is independent of ROS induction and activation of ER stress. The novel signaling pathway of CBP-driven toxicity that was found in the HEp2 cell line, i.e. increased ROS formation and induction of ER stress, may be predictive for therapeutic response of epithelial cancer cells to CBP-based therapy

Pollination patterns of flora and vegetation in northern Croatia with reference to Apis mellifera

Pollination patterns i.e. the proportions of entomophilous, anemophilous, autogamous and hydrophilous plant species and those useful for the European honey bee (Apis mellifera L.) in the flora and vegetation of northern Croatia have been determined. The survey included 507 plant taxa, belonging to 95 plant families. The results show that most plant species depend on insect pollination (73.6%), followed by self-pollination (30%), wind (25%) and water pollination (0.6%). For some plant species there are one, two or more modes of pollination; the largest group consists of pure insect pollination (43%), followed by both insect and self-pollination (27%), pure wind pollination (22%), insect and wind pollination (2.6%), and so on. Overall, 54% of plant species useful to European honey bees were found, of which 51% provide pollen and 47% nectar. These results suggest that A. mellifera could be a potential pollinator for about half of the flora. Analysis shows significant differences in pollination patterns among habitat types and that most entomophilous plant taxa are found in grassland, forest and ruderal sites, indicating that these habitats are most important for pollinators. Other characteristics of plant species, such as flowering time, plant family, life form and origin, were also analysed to determine a possible relationship with pollination

The Zrmanja River Estuary (Adriatic Coast, Croatia) – the Need for Interdisciplinary Approach to Protection of Coastal Areas

The Zrmanja River estuary is a semi-enclosed bay immersed in a karstic landscape of the eastern Adriatic coast. It represents a highly indented system which includes part of the Zrmanja River, downstream from the Jankovića Buk, the Novigrad and the Karin Seas, and the strait connecting the Novigrad Sea with the Velebit Channel. The very fact that the estuary of the Zrmanja River is located in the karst area makes this system highly vulnerable and susceptible to possible anthropogenic pressures. Preservation of such and similar water systems relies on the knowledge of the main factors that govern its physical, chemical, biological and geochemical features. Due to the lack of geochemical data for the Zrmanja River estuary, a comprehensive study was carried out to explain sedimentation processes and the origin of the material within this estuary and provide additional knowledge necessary for its sustainable use and preservation. This paper, therefore, attempts to summarize the obtained data, focusing on the main natural and anthropogenic factors that define the geochemistry of the Zrmanja River estuary

Discovering Europe? Identity of the Migrants in the EU

This paper focuses on migration in Europe and European identity. Above all, it aims to explore the capacity of European identity to offer an inclusive form of collective affiliation both for intra- and extra-European migrants. We argue that the probability for both, extra- and intra-EU migrants, to develop European identity is higher than the probability to develop country-of-residence identity since the later one is based on ascriptive criteria and therefore exclusive in its nature. Social scientists from different traditions started only recently to deal with those questions focusing, above all, on the effects of mobility within EU borders on identity and attitudes towards Europe (Favel, 2009; Recchi and Favel, 2009). Our research aims to contribute to this theoretical and empirical debate by analysing also extra-European migrants. The high magnitude of extra-EU immigration (more than 30 million, out of the total 47 million of migrants that reside in EU countries were born outside the EU according to Eurostat 2011) clearly shows the importance of the relationship between migrants and European identity. In our empirical analyses we will rely on 2009 Eurobarometer (EB) and 2009 European Election Survey (EES) dat

Geochemical characteristics of sediments of the Novigrad sea area

Novigradsko more uvučeni je zaljev Jadranskog mora u čijem se sjeveroistočnom dijelu ulijeva rijeka Zrmanja tvoreći visokostratificirani estuarij. Istraživanje geokemijskih, sedimentoloških i mineraloških značajki sedimenata šireg područja Novigradskog mora provedeno je u svrhu određivanje podrijetla materijala, uvjeta taloženja te prirodnih i antropogenih faktora utjecaja na sedimentaciju u Novigradskom moru. Rezultati istraživanja pokazali su da je sastav recentnih sedimenata Novigradskog akvatorija određen prvenstveno prirodnim čimbenicima, iako sporadično nalazimo i utjecaj antropogenog djelovanja. Sastav istraživanih recentnih sedimenata, osim geološkom podlogom, hidrodinamskim uvjetima i biogenom produkcijom, uvjetovan je i fizikalnokemijskim procesima koji reguliraju donos otopljene i partikulatne faze rijekama Zrmanjom i Karišnicom te koagulacijom donešenog koloidnog materijala duž gradijenta saliniteta. Materijal donešen rijekom Zrmanjom dijelom se taloži na ušća rijeke u Novigradsko more dok se neistaloženi materijal u suspenziji odnosi dalje i taloži u dubljim dijelovima bazena. Reoksidacija metalnih oksida na granici voda-sediment čini sedimente Novigradskog mora mjestom odlaganja metala. Zatvorenost bazena i ograničena izmjena vode s Novigradskim morem uvjetuje u Karinskom moru pojavu suboksičnih uvjeta. Većina materijala donešena rijekama Zrmanjom i Karišnicom zadržava se na području Novigradskog i Karinskog mora. Sastav sedimenata rijeke Zrmanje upućuje na utjecaj tvornice Jadral i prijenos materijala iz njezine neposredne blizine u vodeni sustav rijeke Zrmanje vjetrom. Sastav površinskih i pridnenih voda istraživanog područja odražava geološku i hidrogeološku podlogu, dok je raspodjela u vodenom stupcu uvjetovana salinitetom i remobilizacijom elemenata iz sedimenta u vodeni stupac.Novigrad Sea is a small bay of the Adriatic Sea in which northeastern part Zrmanja River discharges and forms highly stratified estuary. Investigation of geochemical, sedimentological and mineralogical characteristics of sediments of wider area of the Novigrad Sea was conducted in order to determine the origin of the material, the deposition conditions as well as natural and anthropogenic factors of influences on sedimentation in the Novigrad Sea. The results showed that the composition of the Novigrad Sea sediments is primarily determined by natural factors, although sporadically we find the impact of anthropogenic activities. Composition of the investigated sediments is influenced by geological background, hydrodynamic conditions, biogenic production as well as the physico-chemical processes that govern the yield of dissolved and particulate phases of the Zrmanja River and Karišnica River and coagulation of colloidal materials along the salinity gradient. Material brought by Zrmanja River partly deposits on the mouth of the river in the Novigrad Sea while the material in suspension deposits in the deeper parts of the basin. Reoxidation of metal oxides at the water-surface interface makes Novigrad Sea sediments place of trace element disposal. Most of the material brought by River Zrmanja and River Karišnica deposits within the Novigrad Sea and the Karin Sea area. The composition of the Zrmanja River sediments indicates the impact of the ex-alumina factory Jadral and transfer by wind of the material from its immediate proximity to the water system of the Zrmanja River. The composition of surface and bottom water of the Novigrad Sea area reflects the geological and hydrogeological background, while the distribution of trace elements in the water column is determined by salinity and remobilization of elements from the sediment into the water column