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To evaluate the serotype distribution and antibiotic resistance in pneumococcal infections in adults and to provide a perspective regarding serotype coverage of both current and future pneumococcal vaccines. This passive surveillance study was conducted with the Streptococcus pneumoniae strains isolated from the specimens of patients with pneumonia (materials isolated from bronchoalveolar lavage), bacteraemia, meningitis, pleuritis and peritonitis between 2015 and 2018. Serogrouping and serotyping were performed by latex particle agglutination and by conventional Quellung reaction using commercial type-specific antisera, respectively. The strains were analysed for penicillin, cefotaxime, erythromycin and moxifloxacin susceptibilities by E-test. In the whole study group (410 samples from adults aged ≥18 years), the most frequent serotypes were 3 (14.1%), 19 F (12%) and 1 (9.3%). The vaccine coverage for PCV13, PCV15, PCV20 and PPV23 was 63.9%, 66.6%, 74.1% and 75.9%, respectively, in all isolates. Penicillin non-susceptibility in invasive pneumococcal disease (IPD) was 70.8% and 57.1% in the patients aged <65 and ≥65 years, respectively. About 21.1% and 4.3% of the patients with and without IPD had cefotaxime resistance. Non-susceptibility to erythromycin and moxifloxacin was 38.2% and 1.2%, respectively. The results revealed that novel PCV vaccines may provide improved coverage as compared with the currently available vaccine, PCV13. The significant antibiotic resistance rates imply the need to extend the serotype coverage of the vaccines. Continuing the surveillance in pneumococcal diseases is critical to explore the serotype distribution and incidence changes of IPD cases in the population and to inform policy makers to make necessary improvements in the national immunization programmes. This multicentre study demonstrated the most recent serotype distribution and antibiotic resistance in adult population in Turkey. Shifting from PCV13 to novel conjugated vaccines will significantly increase the coverage. Continuing the surveillance in pneumococcal diseases is critical to explore the serotype distribution changes and the incidence of cases with invasive pneumococcal disease in the population. [ABSTRACT FROM AUTHOR]

Voluminous moderate- to high-magnesian [Mg# = molar Mg/(Mg + Fe2+) = 44–64] andesitic and dacitic rocks with high silica (mostly 61–66 wt%) adakitic affinity (Y = 13–22, Yb = 1.3–2.1, Sr/Y = 18–44, La/Yb = 10–25) and common mafic magmatic enclaves (MMEs) are first reported in the Keçiboyduran stratovolcano (KSV) from the Cappadocia volcanic province (CVP), Central Anatolia, Turkey. We present comprehensive whole-rock geochemistry and Sr–Nd–Pb isotope data, mineral chemical compositions and 40Ar–39Ar ages for KSV samples. Based on the volcanostratigraphy and 40Ar–39Ar dating results, two successive eruption ages of 2.2–1.6 Ma (stage I: amphibole-rich) and 1.6–1.2 Ma (stage II: pyroxene-rich) were established for the KSV, corresponding to the Gelasian and Calabrian stages of Early Pleistocene, respectively. Textural and geochemical evidence indicates that the KSV magnesian andesites–dacites are products of a hybrid magma formed by mixing between mantle-derived mafic and crust-derived felsic magmas with further fractionation and minor contamination during magma storage and ascent. Our new data, combined with previous geological and geophysical results suggest that parental magnesian mafic melts of the KSV rocks originated from a heterogenous mantle source generated through the metasomatism of mantle wedge material by subducted sediment-derived melts, and then partially melted through asthenospheric upwelling in response to slab break-off. The mafic magma underplated the overlying lower crust, resulting in its partial melting to generate crustal felsic magma. Both magmas mixed at lower crustal levels creating MME-rich hybrid magmas. Subsequently, the hybrid magmas were emplaced at different depths of the crust (c. 4–11 and 11–15 km for the stage I and II, respectively), where they crystallized at moderate temperatures (c. 1180–840 °C) and under relatively high oxygen fugacity (LogƒO2 = − 11.4 to − 9.2), water-rich (H2Omelt = 5.6–3.6 wt%) and polybaric (~ 1.2 to 5.1 kbars) conditions, and underwent fractionation of primarily amphibole ± pyroxene causing adakitic affinity. We propose a new petrogenetic model for the early Quaternary magnesian/adakitic andesites/dacites of the CVP in a post-subduction tectonic setting. Our results provide robust evidence for slab break-off of the eastern Cyprus oceanic lithosphere and put further constraints on the tectonic evolution of the eastern Mediterranean collision zone during the Early Quaternary. [ABSTRACT FROM AUTHOR]

Postcollisional magmatism in the eastern Sakarya zone was recorded by voluminous basic volcanism and repeated plutonism during the early Cenozoic. The temporal and geochemical evolution of these magmatic rocks is important for understanding the possible geodynamic history of the Sakarya zone. Here, we investigated three representative plutons lying between the towns of Çamlıhemşin (Rize) and İspir (Erzurum), Turkey. These are largely composed of medium-K gabbroic diorites (Marselavat Pluton), shoshonitic monzonites (Güllübağ Pluton), and high-K granites (Ayder Pluton). We present whole-rock geochemistry, 40Ar/39Ar geochronology, and Sr, Nd, and Pb isotope analyses from the plutons to constrain the timing of variations in magmatism and source characteristics, and we provide a new approach to the proposed geodynamic models, which are still heavily debated. The 40Ar/39Ar geochronology reveals a cooling sequence from ca. 45 Ma for the Marselavat Pluton through ca. 41 Ma for the Güllübağ Pluton to ca. 40 Ma for the Ayder Pluton. Whole-rock geochemistry and Sr, Nd, Pb isotopes suggest that crustal contamination was not an important factor affecting magma compositions. Although there was no arc-related tectonic setting in the region during the middle Eocene, the Marselavat Pluton shows some subduction affinities, such as moderately negative Nb and Ta anomalies, and slightly positive Pb anomalies. These signatures were possibly inherited from a depleted mantle source that was modified by hydrous fluids released from the oceanic slab during Late Cretaceous subduction. Geochemical traces of the earlier subduction become uncertain in the Güllübağ samples. They display ocean-island basalt-like multi-element profiles and Nb/Ta, Ce/Pb, and La/Ba ratios. All these point to a mantle source in which earlier subduction signatures were hybridized by the addition of asthenospheric melts. Melting of calc-alkaline crustal material, probably emplaced during the first phase of middle Eocene magmatism (Marselavat), led to the formation of granitic plutonism (Ayder Pluton). Our data in conjunction with early Eocene adakite-like rocks show that melt generation, as in the given sequence, was most probably triggered by breakoff of the northern Neotethyan oceanic slab, ~13 m.y. after the early Maastrichtian collision between the Sakarya zone and Anatolide-Tauride block, and continued until the end of the middle Eocene. A shallow-marine transgression occurred contemporaneously with the middle Eocene magmatism throughout the Sakarya zone. An extension in this magnitude seems unlikely to be the result of orogenic collapse processes only. The main cause of this extension was most probably related to the northward subduction of the southern Neotethys Ocean beneath the Anatolide-Tauride block. The result is a volumetrically larger amount of middle Eocene magmatism than that expected in response to slab breakoff. [ABSTRACT FROM AUTHOR]

The eastern Blacksea magmatic arc (EBMA) in the eastern Sakarya Zone (ESZ) provides an excellent opportunity to investigate birth of an extensional intra-arc and back-arc settings in the Late Cretaceous over the Early Cretaceous northern passive margin of the Neotethys Ocean. Volcano-stratigraphy clearly shows that the Late Cretaceous volcanic activity of the EBMA occurred in two major phases. Bimodality, characterized by mafic/basaltic rocks at the base and felsic/silicic types on top of it, is a typical feature of the lower (LVS) and upper (UVS) volcanic successions in the Giresun region of the ESZ. U Pb and Ar Ar ages support the volcanic succession as two-stage (LVS: ca. 92–85 and UVS: ca. 83–67 Ma) bimodal volcanism. Both the volcanic successions are represented by similar rock types consisting of tholeiitic to calc-alkaline basalt-basaltic andesites and calc-alkaline to shoshonitic dacite-rhyolites. Basaltic (M1- and M2-series) and felsic/silicic (F1- and F2-series) samples of the LVS and UVS have an arc-like signature with enriched large ion lithophile elements (LILEs) and light rare earth elements (LREEs) and depleted high field strength elements (HFSEs). Also, the felsic/silicic samples of the F1- and F2-series show prominent negative Sr and Eu anomalies (Eu/Eu* = 0.4 to 0.9), suggesting that plagioclase fractionation played a key role on the evolution of both felsic series. Bimodal rock series in two phases have a wide range of 87Sr/86Sr (i) (0.7048–0.7075) and 143Nd/144Nd (i) (0.5123–0.5127) ratios with variable ɛNd (i) values of −3.8 to +3.0. 206Pb/204Pb (i) , 207Pb/204Pb (i) and 208Pb/204Pb (i) isotope ratios of the Giresun volcanic rocks vary in the range of 17.97–18.52, 15.55–15.65 and 37.53–38.56, respectively. Geochemical and isotopic data suggest that the parental magma of the M1-basaltic rocks were probably derived from a shallow (spinel-bearing) mantle metasomatized by slab/sediment-derived fluids. In contrast, the M2-basalts seem to have been originated from a deeper mantle source (spinel-garnet transition zone) enriched by slab/sediment-derived fluids and hydrous melts (bulk sediment) metasomatism with some contributions of lower/upper crustal materials. The least evolved basaltic samples in two phases are consistent with moderate (∼10–15%) to high degree (∼20–30%) partial melting of the metasomatized mantle. The silicic melts of the F1- and F2-rocks series, on the other hand, were likely derived from melting of lower crustal materials consisting of meta-basalts/andesites and lesser amount of meta-sediments. Subsequently, these melts experienced FC ± AFC and mixing processes during their ascent and emplacement to generate high-silica (rhyolitic) melts. Our data, combined with previous studies, suggest that two-stage bimodal volcanic rocks of the Late Cretaceous in the ESZ were formed in the transition from an extensional continental intra-arc to a back-arc setting during the northward subduction of the northern branch of Neotethys Ocean. [Display omitted] • Late Cretaceous two-stage (92–85 and 83–67 Ma) bimodal volcanism in the ESZ. • Bimodality is characterized by basaltic and dacitic-rhyolitic rocks in both stages. • Basaltic rocks were derived from mantle metasomatized by slab/sediment fluids±melts. • Dacite-rhyolites were originated from the melting of a heterogeneous crustal source. • Two-stage bimodal volcanism formed in an extensional arc/back-arc setting. [ABSTRACT FROM AUTHOR]

The Maçka subvolcanic intrusions (MSIs) in the eastern part of the Sakarya zone, northeastern Turkey, play a critical role in understanding the petrogenetic and geodynamic processes that took place during the growth of Late Cretaceous arc crust of this region. U–Pb zircon (79.97 ± 0.97 Ma) and two40Ar–39Ar amphibole ages (average 81.37 ± 0.5 Ma) indicate that the MSIs were emplaced in Late Cretaceous (Campanian) time into the coeval volcanic rocks. A slightly younger zircon fission track (FT) age (73 ± 9 Ma) points to a rapid exhumation and cooling after crystallization. The intrusions are observed in areas less than 1 km2in the field and contain abundant mafic microgranular enclaves (MMEs). The host rocks (HRs) are entirely composed of tonalite (SiO2 = 63–65 wt.%, Mg# = 43–52), and the MMEs are gabbro-diorite in composition (SiO2 = 53–57 wt.%, Mg# = 45–48). Both the HRs and the MMEs are I-type, high-K calc-alkaline in composition and display a metaluminous character. They are characterized by geochemical features typical for magmas of subduction-related environments. Chondrite-normalized REE patterns are moderately fractionated [(La/Yb)N = 6–11] and display slightly negative Eu anomalies (Eu/Eu* = 0.7–0.9), with weak concave-upward REE patterns, suggesting that amphibole fractionation played a role during their evolution. The MMEs have slightly differentISr(0.7081–0.7085) and εNd(−5.0 to −5.4) values compared with those of their HRs (ISr = 0.7084–0.7087 and εNd = −5.7 to −6.9), indicating that variable amounts of crustal and mantle components were involved in the generation of parental magma to these rocks. All of these data, combined with those of previous regional studies, suggest that the MSIs are hybrid in origin, produced by the mixing of enriched lithospheric mantle- and lower crust-derived melts in an extensional arc setting that was caused by slab rollback. [ABSTRACT FROM AUTHOR]

Early Eocene adakitic volcanic and granitoid rocks are widespread in the Eastern Pontides of NE Turkey, providing significant constraints for the early Cenozoic tectonomagmatic evolution of the region. These adakitic rock units exhibit relatively high Sr/Y and La/Yb ratios, but low Y and Yb values, similar to modern adakites generated by partial fusion of a subducted oceanic slab. They also have high K2O and low MgO contents, and show moderately enriched ISrand low ϵNd(t) isotopic signatures. Our trace element modelling suggests that these adakitic magmas were generated from partial melting at low pressures of a garnet-bearing amphibolitic source in the continental lower crust. This lower crustal melting resulted from slab break off-induced asthenospheric upwelling and related magmatic underplating beneath the Eastern Pontides. We interpret this melting event and the adakitic magmatic activity as a syn- to post-collisional process involving early Cenozoic collision of the Pontide and Anatolide–Tauride continental blocks. The geochemical and tectonic constraints presented here indicate that early Eocene adakitic magmatism in the Eastern Pontides did not result from partial fusion of a subducted oceanic slab, but instead represent continental-type adakite formation. [ABSTRACT FROM AUTHOR]

Protracted pre-eruptive zircon residence is frequently detected in continental rhyolites and can conflict with thermal models, indicating briefer magma cooling durations if scaled to erupted volumes. Here, we present combined U-Th and (U-Th)/He zircon ages from the Acigöl rhyolite field (Central Anatolia, Turkey), which is part of a Quaternary bimodal volcanic complex. Unlike other geochronometers, this approach dates crystallization and eruption on the same crystals, allowing for internal consistency testing. Despite the overall longevity of Acigöl rhyolite volcanism and systematic trends of progressive depletion in compatible trace elements and decreasing zircon saturation temperatures, we find that zircon crystallized in two brief pulses corresponding to eruptions in the eastern and western part of the field during Middle and Late Pleistocene times, respectively. For Late Pleistocene zircon, resolvable differences exist between interior (average: 30.7 ± 0.9 ka; 1 σ error) and rim (21.9 ± 1.3 ka) crystallization ages. These translate into radial crystal growth rates of ~10 to 10 cm/s, broadly consistent with those constrained by diffusion experiments. Rim crystallization and (U-Th)/He eruption ages (24.2 ± 0.4 ka) overlap within uncertainty. Evidence for brief zircon residence at Acigöl contrasts with many other rhyolite fields, suggesting that protracted zircon crystallization in, or recycling from, long-lived crystal mushes is not ubiquitous in continental silicic magma systems. Instead, the span of pre-eruptive zircon ages is consistent with autochthonous crystallization in individual small-volume magma batches that originated from basaltic precursors. [ABSTRACT FROM AUTHOR]

We present elemental and Sr–Nd–Pb isotopic data for the magmatic suite (~79 Ma) of the Harşit pluton, from the Eastern Pontides (NE Turkey), with the aim of determining its magma source and geodynamic evolution. The pluton comprises granite, granodiorite, tonalite and minor diorite (SiO = 59.43–76.95 wt%), with only minor gabbroic diorite mafic microgranular enclaves in composition (SiO = 54.95–56.32 wt%), and exhibits low Mg# (<46). All samples show a high-K calc-alkaline differentiation trend and I-type features. The chondrite-normalized REE patterns are fractionated [(La/Yb) = 2.40–12.44] and display weak Eu anomalies (Eu/Eu* = 0.30–0.76). The rocks are characterized by enrichment of LILE and depletion of HFSE. The Harşit host rocks have weak concave-upward REE patterns, suggesting that amphibole and garnet played a significant role in their generation during magma segregation. The host rocks and their enclaves are isotopically indistinguishable. Sr–Nd isotopic data for all of the samples display I = 0.70676–0.70708, ε(79 Ma) = −4.4 to −3.3, with T = 1.09–1.36 Ga. The lead isotopic ratios are (Pb/Pb) = 18.79–18.87, (Pb/Pb) = 15.59–15.61 and (Pb/Pb) = 38.71–38.83. These geochemical data rule out pure crustal-derived magma genesis in a post-collision extensional stage and suggest mixed-origin magma generation in a subduction setting. The melting that generated these high-K granitoidic rocks may have resulted from the upper Cretaceous subduction of the Izmir–Ankara–Erzincan oceanic slab beneath the Eurasian block in the region. The back-arc extensional events would have caused melting of the enriched subcontinental lithospheric mantle and formed mafic magma. The underplating of the lower crust by mafic magmas would have played a significant role in the generation of high-K magma. Thus, a thermal anomaly induced by underplated basic magma into a hot crust would have caused partial melting in the lower part of the crust. In this scenario, the lithospheric mantle-derived basaltic melt first mixed with granitic magma of crustal origin at depth. Then, the melts, which subsequently underwent a fractional crystallization and crustal assimilation processes, could ascend to shallower crustal levels to generate a variety of rock types ranging from diorite to granite. Sr–Nd isotope modeling shows that the generation of these magmas involved ~65–75% of the lower crustal-derived melt and ~25–35% of subcontinental lithospheric mantle. Further, geochemical data and the Ar–Ar plateau age on hornblende, combined with regional studies, imply that the Harşit pluton formed in a subduction setting and that the back-arc extensional period started by least ~79 Ma in the Eastern Pontides. [ABSTRACT FROM AUTHOR]

Clinopyroxene phenocrysts and microphenocrysts in different series of the Neogene alkaline volcanic rocks from the eastern Pontides (NE Turkey) record various stages in the crystallization conditions and evolution history of the alkaline melt as well as its origin. Crystal chemical studies reveal that the clinopyroxenes in each rock series show strong textural and compositional similarities, which all reflect a common petrogenetic affinity. They have relatively high Mg-numbers (0.68-0.95). variable Al2O3 (1.3 - 9.6 wt%), low TiO2 (<2.7 wt%) and Na2O (<0.9 wt%) contents and low Al[6]/Al[4] ratios (mostly <0.25), suggesting relatively low-pressure crystallization conditions of the magma in the storage region. The pressures calculated for the clinopyroxenes in each series are nearly similar and vary in the range of 2.4-4.6 ± 0.9 kbars, which approximately corresponds to a crystallization depth of 7- 14 ± 3 km. The analyses of the compositional trends of the clinopyroxenes indicate the following types of zoning: (i) oscillatory and sectorial zoning related to melt crystallization (i.e. rapid cooling and crystallization), (ii) oscillatory, reverse zoning related to the different crystallization paths under a variable fluid regime, (iii) normal zoning related to the differentiation and fractional crystallization of the magma. Based on the primitive mantle- and chondrite-normalized trace and rare earth element patterns, all clinopyroxenes have high abundances of incompatible elements (i.e. La, Ce) with negative high field strength element anomalies (i.e. Zr, Ti) and low Nb/Y (0.1-0.2). Th/Y (<0.1) and Rb/Y (<0.03) ratios, suggesting derivation from a similar source. Obtained textural and mineral chemical data, as well as whole-rock compositions, thus suggest that the clinopyroxenes may have started to crystallize from alkaline basaltic magma derived from a homogeneous lithospheric mantle enriched by an earlier subduction event. After this process, the alkaline magma, from which early clinopyroxenes crystallized, underwent a relatively low-pressure fractional crystallization process. This was in closed magma chambers at different levels of the crust (or within a volcanic conduit system devoid of interaction processes), shown by variations in the different crystallization paths and in the fluid regime of the melt during differentiation and ascent of the magma, in a post-collisional extensional tectonic regime which affected the eastern Pontides during the Neogene. [ABSTRACT FROM AUTHOR]

Magnetite-ulvtispinel and ilmenite-hematite solid solution intergrowths from the high-K calc-alkaline DOlek and Sarıçiçek plutons, Eastern Turkey, were investigated using microprobe analyses. Compositions of twenty-eight samples from the host rocks and their enclaves in the plutons were used to estimate the oxygen fugacity and temperature. The ilmenite and ulvospinel component exsolves out along certain preferred crystallographic planes in the titanomagnetite of the host rocks, while they are always absent in those of the mafic microgranular enclaves. The titanomagnetite and ilmenite show variations as Mt98-70Usp02-30 and llm99-65Hm01-35 in composition, respectively. Estimations of oxygen fugacity and temperature using the titanomagnetite-ilmenite thermometry/oxygen barometry range from logfO2 of -15.30 to -20.48 in host rocks, l0gfO2 of-15.39 to -20.80 in the mafic microgranular enclaves and 617±6 to 758±23 °C in host rocks, 622±6 to 735±24 °C in the mafic microgranular enclaves, possibly indicating crystallisation temperature. Applying magnetite-ilmenite thermometry/oxygen barometry to the granitoid rocks also involves microprobe analyses of ilmenite lamellae in titanomagnetite and this method yielded mean temperatures of 679±18 T. The specific forms and chemical properties of Fe-Ti oxides, and similarities in crystallization temperature and oxygen fugacity of the host rocks and the mafic microgranular enclaves (MME) obtained from the Fe-Ti oxide pairs imply that thermal equilibrium probably occurred between two contrasted magmas. which mixed in various proportions so that possibly a felsic and a more mafic magma interaction occurred in a convectively dynamic magma chamber during crystallization of the plutons. Probably, underplating may be responsible for genesis of the hybrid plutons. Thus, for mixing of coeval magmas derived from a lithospheric upper mantle (mafic end-member) and lower crust (felsic end- member), a thermal anomaly should be supplied. Upwelling of hot asthenospheric material results in thermal perturbation and melting of lithospheric mantle. Intrusion of hot lithospheric mantle-derived mafic magma then induced lower crustal melting, producing felsic melt. Mixing of the lower crust-derived melt and lithospheric mantle-derived magma formed the hybrid plutons. This process requires a post-collisional extensional tectonic setting during the Eocene in the Eastern Pontides. [ABSTRACT FROM AUTHOR]

The aim of the present report was to evaluate the prevalent species of airborne fungi in the outdoor environment in the city of Trabzon, Turkey. The area is surrounded by high mountains running parallel to the Black Sea, and has a mostly rainy and temperate climate together with a most varied and widespread flora. Air samples were collected in four seasons by means of the gravitational settling method using petri dishes with SDA culture media. Those fungi colonies that formed after an incubation period of 7–10 days at 25 °C were determined on the basis of micro and macromorphological features. With respect to seasons, it was found that in Summer Penicillium, Alternaria and Fusarium, in Autumn and Winter Penicillium and in Spring and Summer Alternaria were the most prevalent fungal genera. [ABSTRACT FROM AUTHOR]

Plagioclase crystals characterized by compositional zoning are typical of the Zigana Granitoid (ZG), NE Turkey. The zoned crystals, which show textural equilibrium with the assemblage quartz + plagioclase + K-feldspar + hornblende + biotite + pyroxene + magnetite + ilmenite, exhibit oscillatory zoning. The zoned plagioclase crystals, ranging in size from 3 to 6 mm, are oval and larger than normal lath-shaped crystals. The zoned crystals are divided petrographically into two main types: (i) crystals zones only at their rims, with spongy cores; and (ii) completely zoned ones. Composition of the zoned crystals ranges from An23 (oligoclase) to An70 (labradorite). Plagioclase crystals with oscillatory zoning are governed by strong substitution mechanisms of Ca2+ ⇔ Na+, Al3+ ⇔ Si4+ and weak substitution of Fe3+ for Si++. The Fe2O3(t) (wt %) contents of the subject plagioclases increase with increasing An content. The petrographic and compositional changes from rim to rim (oscillatory zoning), and positive correlation between Fe2O3(t) (wt %) and An (mol %) contents of the zoned plagioclases, suggest recurrent mafic magma injection into a felsic magma chamber, and thus magma interaction as a dominant magmatic process during the evolution of the Zigana Granitoid (ZG). [ABSTRACT FROM AUTHOR]

• Late Cretaceous volcanism of the ESZ erupted in two successive stages. • The successive stages are characterized by mafic and felsic volcanic rocks. • Mafic rocks of both stages were derived from underplated basaltic melts. • Composition of the felsic rocks was controlled by MASH and crustal processes. • Volcanism took place during northward subduction of the northern Neotethys Ocean. The Late Cretaceous Artvin volcanic rocks (LCAVs) from the eastern Sakarya zone (ESZ) of NE Turkey are composed of mafic/basaltic (S1-Çatak and S2-Çağlayan) and felsic/acidic (S1-Kızılkaya and S2-Tirebolu) rock types that occurred in two successive stages: (i) first stage (S1: Turonian–Early Santonian) and (ii) second stage (S2: Late Santonian–Campanian). Clinopyroxene thermobarometric results point that the S2-Çağlayan basaltic rocks have crystallised at higher temperatures and under deeper crustal conditions than those of the S1-Çatak basaltic rocks. The LCAVs show a wide compositional spectrum, ranging from tholeiite to calc-alkaline/shoshonite and are typically represented by a geochemical composition resembling subduction-related arc rocks although the 87Sr/86Sr (i) (0.7044–0.7071) and ɛNd (i) values (−0.63 to + 3.47) as well as 206Pb/204Pb (i) (18.07–18.56), 207Pb/204Pb (i) (15.57–15.62) and 208Pb/204Pb (i) (37.12–38.55) ratios show very limited variation. The parent magmas of the S1-Çatak and S2-Çağlayan mafic volcanic rocks were derived from underplated basaltic melts that originated by partial melting of metasomatised spinel lherzolite and spinel-garnet lherzolite, respectively. It is proposed that the compositions of the S1-Kızılkaya (mainly dacitic) and S2-Tirebolu (rhyolitic to trachytic) felsic rocks were particularly controlled by metasomatised mantle–crust interaction and MASH zone + shallow crustal fractionation processes. Our data, together with data from previous studies, suggest that the S1- and S2-mafic and felsic rocks of the LCAVs (~95–75 Ma) are the products of two-stage volcanic event that took place during the northward subduction of the northern Neotethys Ocean (NNO). [ABSTRACT FROM AUTHOR]

Turkey's Early Paleozoic tectonic evolution has received much attention in recent years. Early Paleozoic intrusive rocks are mainly distributed across Europe, Turkey (İstanbul-Zonguldak Zone, Strandja Zone, and Tauride Block), and Iran. However, the Early Paleozoic rocks have not yet been identified in north Turkey's Sakarya Zone, and thus the Early Paleozoic paleogeography of the Sakarya Zone remains enigmatic. Here, we provide new field observations, petrography, geochemistry, and geochronology of the western Sakarya Zone to identify the nature, origin, and tectonic setting of the Ordovician magmatic rocks cropping out in the Söğüt area (Bilecik, northwest Turkey). Our Laser Ablation Inductively Coupled Plasma Mass Spectrometry (LA-ICP-MS) U Pb analyses on zircons suggest that the Söğüt metagranites were emplaced at ∼484–461 Ma (except two zircons with ages of 490 and 494 Ma). There are abundant inherited zircon cores in the Söğüt metagranites, with ages of >500 Ma to ∼2.2 Ga. The inherited Cadomian cores give concordant ages of 588 and 572 Ma. The Söğüt metagranites are felsic and have high SiO 2 (72–76 wt%) and K 2 O (4.1–5.3 wt%) contents, with high K 2 O/Na 2 O ratios (1.2–1.9), and low Mg# (17–35) values. The samples are Ca-poor (CaO = 0.52–0.68 wt%) and show peraluminous [A/CNK = molar Al 2 O 3 /(K 2 O + CaO + Na 2 O) = 1.15–1.28] and high-K calc-alkaline geochemical characters, with high modal content of muscovite (∼10%), consistent with S-type compositions. The samples have low REE concentrations, with negative Eu anomalies. Ordovician zircon rims show εΗf (t) values of +3.6 to −35.4, whereas inherited zircon cores have εΗf (t) values of +33.9 to −26.1. Our data, in conjunction with previous studies, suggest that the Söğüt metagranites were generated by fluid-absent muscovite-dehydration melting of metasediments accumulated in a back-arc setting. This back-arc basin was characterized by a denuded continental crust with abundant pelite-dominated sediments and minor input of juvenile mafic melts. Our results, combined with previously published data and paleogeographic reconstructions, allow us to conclude that the Ordovician S-type granites were formed by progressive back-arc extension and crustal thinning prompted by the rollback of the southward subducting oceanic-lithosphere slab. This led to the opening of the Rheic Ocean on the northern side of Gondwana in response to the final closure and termination of the Tornquist Ocean as a branch of the Iapetus Ocean. We argue that the Ordovician S-type granites from the northern side of Gondwana could signal significant crustal reworking away from any clear continental collision zone. [Display omitted] • Ordovician S-type granites have been reported for the first time in Sakarya Zone. • The S-type granites were formed by the melting of a metapelitic source. • Our data confirm that the S-type granites originated in a subduction setting. • We propose that the crustal reworking may occur away from continental collision. [ABSTRACT FROM AUTHOR]

• The Early Eocene porphyries are I-type metaluminous in composition. • These porphyries were derived from an enriched mantle domain. • Infiltration of asthenosphere due to slab break-off event triggered partial melting. • The porphyries represent an early stage of extensional tectonic in the Sakarya Zone. The initiation of the break-off of the northern branch of the Neotethyan oceanic lithosphere is an important but poorly understood event in the geology of the Sakarya Zone (SZ) in northeastern Turkey. Although it is well-known that Latest Cretaceous intrusives (~70 Ma) and early Eocene adakitic magmatic rocks are present in the eastern SZ, the outcrops of the early Eocene non-adakitic rocks are very limited, and their tectono-magmatic evolution has not been studied. We describe a small outcrop of non-adakitic quartz diorite porphyry in the Kov area of the Gümüşhane region in northeastern Turkey. The genesis of these porphyries is significant in evaluating the syn- to post-collision-related magmatism. The LA-ICP-MS zircon U-Pb dating revealed that the Kov quartz diorite porphyries (KQDP) formed at ca. 50 Ma, coeval with adakitic rocks, and ~20 Myr later than the slab roll-back-related intrusive rocks. The KQDPs are calc-alkaline in composition and enriched in large ion lithophile elements (LILEs) and light rare earth elements (LREEs) and depleted in high field strength elements (HFSEs; e.g., Nb, Ta, Ti), with significant negative anomalies of Nb, Ta, and Ti but positive anomalies of Th, U, and Pb. Isotopic compositions of the samples show limited range of variation and slight enrichment of 87Sr/86Sr(t) (0.70489 to 0.70555), ε Nd (t) (−1.4 to −1.2) with T DM of 1.11 to 1.61 Ga. Pb isotopic ratios of the samples point to an enriched mantle source. They were likely crystallized from the melt that originated from an EM2-type spinel-facies subcontinental lithospheric mantle (SCLM), followed by the fractionation with insignificant crustal assimilation. The SCLM was metasomatically enriched, and the metasomatic agent was likely H 2 O-rich fluids rather than sediments released from subducting oceanic crust during the Late Cretaceous closure of the Neotethyan oceanic lithosphere. In conjunction with the geological background and previous data, we propose that the generation of the KQDPs resulted from a slab break-off event that caused ascending or infiltration of hot asthenosphere, triggering mantle melting. Such sporadic occurrences of the KQDPs, with coeval adakitic rocks in the SZ, are likely associated with the onset of extensional tectonics due to the earlier stage of slab break-off along the region during the early Eocene period. [ABSTRACT FROM AUTHOR]

The timing of major tectonic events and the driving mechanisms for magma generation during Late Cenozoic convergence and collision between Arabia and Eurasia still remain unknown. The Sakarya Zone (SZ) in northern Turkey is a critical member of this collisional assemblage. In the easternmost part of the SZ, we have recognized a Late Miocene volcanic suite termed the Çağirankaya volcanics which displays characteristic post-collisional geochemical features. Here, we report a new data set of zircon U Pb ages, whole-rock major and trace element, as well as Sr Nd isotope analyses for dacite and andesite samples from the Çağirankaya volcanics. Zircon U Pb ages for a selected dacitic lava sample average 5.16 ± 0.11 Ma (mean square of weighted deviates, MSWD = 0.45, n = 35), confirming a late Miocene age of this volcanic episode. The high-K calc-alkaline andesites and dacites exhibit an adakite-like geochemical signature, and are characterized by high Sr (424 to 552 ppm), Sr/Y ratios (31–43), and low Mg# (42 to 46) values, along with low Y (12–14 ppm) and heavy rare earth element (HREE) concentrations, that resemble those in adakites formed by partial melting of hot oceanic slab during subduction. Isotopic compositions are near bulk Earth (87Sr/86Sr(t) = 0.70482 to 0.70489, ε Nd (t) = +1.08 to +1.33), which rules out a solely asthenospheric origin. Elevated Nb/Ta (14 to 17) and K 2 O/Na 2 O (0.6–1.0) imply a juvenile mafic lower crustal source composed of ~20% garnet-bearing amphibolite. Geochemical modeling suggests that adakite-like parental melts were generated in the absence of subduction and without large-scale delamination of lower continental crust. Instead, our findings suggest that Late Miocene adakite-like volcanic rocks in the SZ formed in a post-collisional intra-continental setting, which experienced far-field extension after the subducted slab of the southern Neotethyan branch became detached in the collision zone. Asthenospheric upwelling and underplating of basaltic magma provided the heat for partial melting of lower crustal amphibolite, forming minor amounts of adakite-like melts in the SZ. • The Çağirankaya volcanics erupted in Late Miocene in the Sakarya Zone. • They exhibit adakite-like geochemical signature. • All characteristics suggest that they were derived from a juvenile lower crust. • Upwelling of hot asthenosphere due to far-field forces caused partial melting. • Adakitic melt do not require contemporaneous subduction of a hot oceanic slab. [ABSTRACT FROM AUTHOR]

Cadomian realms have recently received much attention in the Alpine–Mediterranean orogenic belts, with discontinuous outcrops extending from the Alps to the İstanbul Zone, Menderes Massif, Taurides in Turkey and Iran as well. However, they have not been identified in the Sakarya Zone, northern Turkey to date. Here, we present, for the first time, zircon U Pb geochronology, zircon Hf-isotopes and trace elements as well as whole-rock geochemistry and Nd-isotopes from the Karameşe metagranitoid in the Yusufeli (Artvin) area, NE Turkey. The zircon U Pb age data demonstrate that the Karameşe metagranitoid intruded into the Precambrian basement units in the Early Cambrian (ca. 534–530 Ma). Zircon overgrowths in the Karameşe metagranitoid interpreted as a result of metamorphic overprint yielded ages of 328 Ma. This age indicates that the Sakarya Zone experienced the Variscan metamorphic events at 328 Ma. The Early Cambrian metagranitoid shows that some rocks in the basement of the Sakarya Zone date back to Precambrian in age. The Karameşe metagranitoid is an S-type granite, with high modal content of muscovite (~10%). The samples show highly peraluminous [A/CNK = molar Al 2 O 3 /(CaO + K 2 O + Na 2 O) = 1.34–1.58] and medium-K calc-alkaline geochemical affinities. The Karameşe metagranitoid displays low REE concentrations and a slight positive Eu anomaly and show slightly light REEs and LILEs enrichments, and HFSEs depletions. The samples have negative ε Nd (t) of −4.76 to −2.90 and ε Hf (t) of −4.75 to −1.08 values. These geochemical-isotopic characteristics reveal that the Karamaşe metagranitoid originated through fluid-absent muscovite dehydration melting of heterogeneous metasedimentary source rocks (mostly greywacke), with a minor input of juvenile mafic melt. We argue that the Early Paleozoic metagranitoids along the eastern Sakarya Zone is an expression of crustal thinning in the Cadomian orogenic belt in northern Gondwana, with the tectonic turnover from convergent margin to crustal extension possibly induced by break-off of Tornquist oceanic lithosphere which is a branch of Iapetus Ocean during Early Cambrian. [Display omitted] • Cambrian S-type granites have been reported for the first time in Sakarya Zone. • The S-type granites originated from the melting of a metasedimentary source. • Variscan metamorphism overprinted the Early Cambrian magmatism. • Our data reveal that the S-type granites were formed in a post-collision setting. [ABSTRACT FROM AUTHOR]

Abstract: The Eastern Pontides in NE Turkey is one of the major orogenic belts in Anatolia. In this paper, we report our new 40Ar/39Ar dating, mineral chemistry, major and trace elements and Sr–Nd–Pb isotopic analyses of the lamprophyre intrusions in this region. The lamprophyres are widely scattered and intrude Late Carboniferous granitoid rocks. The lamprophyres exhibit fine-grained textures and are mineralogically uniform. Hornblende 40Ar/39Ar dating yielded a plateau age of 216.01±10.64Ma. Based on their geochemistry, mineral compositions and paragenesis, the lamprophyres are classified as calc-alkaline lamprophyres in general and spessartites in particular, which are rich in large ion lithophile elements (e.g., Rb, Ba, K) but depleted in Nb and Ti. Our samples exhibit moderate fractionation in LREE patterns approximately 100 times that of chondrite but HREE abundances less than 10 times that of chondrite. These calc-alkaline lamprophyres display a range of ISr (216Ma) values from 0.70619 to 0.71291 and εNd (216Ma) values from −1.4 to 4.1, with T DM =1.11 to 2.20Ga. Their Pb isotopic ratios indicate an enriched mantle source. The enrichment process is related to metasomatism of a subcontinental lithospheric mantle source, which is caused by a large quantity of H2O-rich fluids, rather than sediments released from oceanic crust at depth during the closure of the Paleotethys Ocean in Triassic times. All of the geochemical data and the trace element modeling suggest that the primary magma of the calc-alkaline to high-K calc-alkaline spessartites was generated at depth by a low degree of partial melting (~1–10%) of a previously enriched lithospheric mantle wedge consisting of phlogopite-bearing spinel peridotite. The ascendance of a hot asthenosphere triggered by extensional events caused partial melting of mantle material. The rising melts were accompanied by fractional crystallization and crustal contamination en route to the surface. All of the geochemical features combined with regional data suggest that the Eastern Pontides calc-alkaline lamprophyres originated in an extensional environment along an active continental margin throughout the Late Triassic. Such an extensional event, causing upwelling of hot asthenosphere, led to the opening of the northern branch of the Neotethys as a back-arc basin farther south of the Eastern Pontides. [Copyright &y& Elsevier]

Abstract: The tectonic setting of the Eastern Pontides during the late Mesozoic to early Cenozoic remains a subject of debate. Petrogenesis of adakite-like granitoid porphyries plays a critical role in determining the nature of the lower continental crust and mantle dynamics during orogenic processes in the region. Here we describe, for the first time, the late Paleocene to early Eocene adakite-like granitoid porphyries from the northern part of the Eastern Pontides although their counterparts in the southern part have recently been found. The adakitic porphyries, which emplaced into the subduction-related Turonian–Santonian volcanics from northern part of the region, consist of I-type calc-alkaline quartz monzonite–tonalite (SiO2 =62.89–65.07wt.%) and high-K calc-alkaline granodiorite–granite associations (SiO2 =69.06–70.43wt.%). The former displays peraluminous to metaluminous signatures, whereas the latter shows peraluminous geochemical character. The granite–granodiorite porphyries have high K2O (3.32–3.84wt.%), and low Na2O (3.48–4.61wt.%) and MgO (0.91–1.04wt.%) relative to the quartz monzonite–tonalite association (K2O=1.50–1.92 wt.%; Na2O=4.08–6.45 wt.%; MgO=1.44–2.07 wt.%). Ar–Ar geochronology studies on the amphibole separates reveal that the adakite-like porphyries have a crystallization ages of 51.34±0.27 to 53.55±0.34Ma. Here, we contend that these rocks were formed by partial fusion of a mafic lower continental crust in a collisional phase but not in a subduction setting. All the samples exhibit the typical geochemical characteristics of adakite, that is, high Sr (250–1141ppm), high Sr/Y ratios (16–147), low Y (6.8–14.8ppm) and low HREE concentrations; they are similar to adakites formed by slab melting associated with the subduction zone. However, the rocks exhibit heterogeneity in isotopic composition, with ISr ranging from 0.70554 to 0.70986, εNd (51Ma) from –8.5 to –0.9 and Nd model ages from 0.72 to 1.26 Ga. The samples are characterized by relatively high Th, Th/U and no significant Eu anomalies, implying that garnet was stable in their source during partial melting. The compositional diversity between rock groups is probably related to partial melting of heterogeneous lower crustal source. All of the features are inconsistent with a slab-melting origin and slab-related petrogenetic model, but instead, they favor an origin by melting of heterogeneous lower continental crust due to a thermal anomaly that was induced by the upwelling of the asthenosphere through a slab break-off in a collisional setting. These interpretations argue against the evidence for the presence of an early Cenozoic arc setting in the Eastern Pontides. Instead, the early Cenozoic time in the region may be attributed to a geodynamic response to a post-collisional uplift phase that occurred along the continent-continent collision between the Pontide and the Anatolide-Tauride blocks. [Copyright &y& Elsevier]

Abstract: Early Cenozoic (48–50 Ma) adakitic volcanic rocks from the Eastern Pontides, NE Turkey, consist of calc-alkaline and high-K calc-alkaline andesite and dacite, with SiO2 contents ranging from 56.01 to 65.44 wt.%. This is the first time that Early Eocene volcanism and adakites have been reported from the region. The rocks are composed of plagioclase, amphibole, quartz, and Mg-rich biotite. They have high and low-Mg# values ranging from 55 to 62 and 13 to 42, respectively. High-Mg# rocks have higher Ni and Co contents than low-Mg# samples. The rocks exhibit enrichments in large ion lithophile elements including the light rare earth elements, depletions in Nb, Ta and Ti and have high La/Yb and Sr/Y ratios. Their relative high I Sr (0.70474–0.70640) and low ε Nd (50 Ma) values (−2.3 to 0.8) are inconsistent with an origin as partial melts of a subducted oceanic slab. Combined major- and trace element and Sr–Nd isotope data suggest that the adakitic magmas are related to the unique tectonic setting of this region, where a transition from a collision to an extension stage has created thickening and delamination of the Pontide mafic lower crust at 50 Ma. The high-Mg adakitic magmas resulted from partial melting of the delaminated eclogitic mafic lower crust that sank into the relatively hot subcrustal mantle, and its subsequent interaction with the mantle peridotite during upward transport, leaving garnet as the residual phase, elevates the MgO content and Mg# of the magmas, whereas low-Mg# magmas formed by the melting of newly exposed lower crustal rocks caused by asthenospheric upwelling, which supplies heat flux to the lower crust. The data also suggest that the mafic lower continental crust beneath the region was thickened between the Late Cretaceous and the Late Paleocene and delaminated during Late Paleocene to Early Eocene time, which coincides with the initial stage of crustal thinning caused by crustal extensional events in the Eastern Pontides and rules out the possibility of an extensional regime before ~50 Ma in the region during the Late Mesozoic to Early Cenozoic. [Copyright &y& Elsevier]

Late Mesozoic evolution of the Neotethys Ocean is critical and still remains unclear along the entire Sakarya Zone (SZ), Turkey, because previous interpretations of the Middle to Late Jurassic rifting of the SZ have not been consensually accepted. We identified, for the first time, the Early Cretaceous dykes intruded into the Late Jurassic and Late Carboniferous bodies in the Çamlıkaya (Erzurum) area in the SZ. Here, we present a data set of new field observations, 40Ar/39Ar geochronology, whole-rock geochemical and Sr–Nd isotopes to find out the tectonic setting of previously undated basic to intermediate igneous rocks. 40Ar/39Ar technique on the groundmass separations yielded the plateau ages of 128.78 ± 1.02 to 122.89 ± 0.82 Ma. The investigated dykes are compositionally divided into two sub-groups: calc-alkaline lamprophyres (CAL) and high-Nb alkaline basalts (HNB). They show enrichment in large ion lithophile elements (LILE: e.g., Rb, Ba, K) and depletion in high field strength elements (HFSE: Nb and Ti) as well as moderate fractionation of light rare earth elements relative to heavy rare earth elements. The HNB have high Mg# (47–66), and relatively unradiogenic Sr 87Sr/86Sr(t) = 0.70385 to 0.70510] and Nd [ε Nd (t) = +0.5 to +5.3] isotopic composition, whereas the CAL possess moderate to high Mg# (32–72), and relatively high Sr 87Sr/86Sr(t) = 0.70586 to 0.71379] and Nd [ε Nd (t) = +1.5 to −9.9] isotopic composition. Early Cretaceous high-angle subduction triggered upwelling of the asthenosphere at 126 Ma, which likely generated a heat anomaly. This anomaly has probably induced melting of the oceanic slab and the metasomatized mantle to form the CAL and HNB. The HNB were generated by low degrees of melting of mantle domain that was previously reacted by oceanic slab-related adakitic melts at the depths of the garnet stability field (≥70 km). However, the CAL were probably formed at shallower mantle levels within the garnet-amphibole field by a relatively higher degree of melting of the mantle, also modified by subducted slab sediments. A new field, age, and petrochemical data from the Early Cretaceous dykes, combined with the presence of Aptian deep-water sediments to the north and the Late Jurassic-Early Cretaceous platform carbonates deposited in the passive margin setting along the entire SZ, imply the initiation of active-margin magmatism in the SZ. We suggest that the coexistence of the Early Cretaceous CAL and HNB points to the formation of an Andean-type active margin above a north-dipping Neotethyan oceanic slab. Their emplacement ages are associated with the inception of the magmatic arc structure and refer to a significant geodynamic turnover from passive-margin to active-margin tectonics along the SZ. • Ar–Ar dating suggest presence of an Early Cretaceous volcanism in the Sakarya Zone. • The CALs and HNBs were originated from an enriched mantle wedge. • All geochemical features indicate that they formed in a subduction setting. • All data refer a geodynamic shift from passive- to active-margin tectonics. [ABSTRACT FROM AUTHOR]

The Rheic Ocean is the most significant Paleozoic ocean that detached peri-Gondwana terranes from the northern Gondwana margin throughout the closure of the Iapetus Ocean. The suture of the Rheic Ocean spreads from Mexico to the Middle East, and the timing of its final closure is well-documented by the rocks formed in the Variscan-Alleghanian-Ouachita orogeny which led to the formation of the supercontinent Pangaea. However, as robust paleomagnetic and quantitative data are mostly lacking, the onset and evolution of the subduction of the Rheic Ocean are highly speculative, and they require further confirmation. Recently, the well-preserved metagranitoids along the western Sakarya Zone (SZ) in Anatolia have been identified, and they provide new data that improve our knowledge on the evolution of the Early Paleozoic Rheic Ocean along the northern Gondwana. Here, we present new geochronological, in situ zircon Hf isotope, and whole-rock geochemical analyses of these metagranitoids from the western SZ to enhance our understanding of the subduction processes of the Rheic Ocean. LA-ICP-MS zircon U-Pb dating demonstrated that the Bozüyük and Borçak metagranitoids from the western SZ were emplaced during the Silurian to Early Devonian (431 ± 2.7 to 403 ± 3.5 Ma). The both granitoids have medium- to high-K, calc-alkaline magmatic character, and exhibit peraluminous to slightly metaluminous geochemical signature. They show a typical arc pattern in terms of trace elements and have a uniform, moderate negative ε Hf (t) of −3.2 to −9.7, with Mesoproterozoic Hf depleted mantle model ages (T DM1 = 1.2 to 1.4 Ga). The geochemical and isotopic characteristics are not consistent with those of depleted mantle melts and melts derived from the crustal rocks in an intracontinental environment. Instead, the parental magma is likely generated from the partial melting of a homogeneous and enriched mantle wedge source. We propose that the Silurian to Early Devonian arc-related magmatism is associated with a northward subduction episode of the Rheic Oceanic lithosphere beneath the peri-Gondwana terranes. Hence, we consider that the opening of Paleotethys Ocean formed in a back-arc basin of subduction in Andean style to the north rather than a continental rift to the south in response to south-directed and short-lived supra-subduction zone (SSZ)-type subduction during the Silurian to Early Devonian. Unlabelled Image • Silurian to Early Devonian magmatism were recognized in the Sakarya Zone. • The metagranitoids originated from an enriched mantle domain. • Asthenospheric upwelling due to slab roll-back caused partial melting of mantle. • All the geochemical features indicate that they formed in a subduction setting. • The closure of Rheic Ocean triggered opening of Paleotethys in back-arc to north. [ABSTRACT FROM AUTHOR]

Background: HCV virus infections are one of the major health problems in the world that can cause cirrhosis and liver cancer at a higher rate than other hepatitis data. The aim of this study was to determine the prevalence of mixed infections with different HCV genotypes in Turkey and also to evaluate the current HCV genotype and sub-type distributions by a multicentered assessment., Methods: The HCV genotype data of 17,578 hepatitis C patients collected from 23 centers from different geographic regions covering all Turkey were collected. The data included information about the HCV genotypes in the last 10 years (between 2007 and 2016), demographic properties of the patients and the methods/systems used to determine the genotypes., Results: Two hundred twenty-eight of the patients (1.3%) had mixed genotype. The most common mixed genotype combination was 1b + 4 (0.83%) followed by 1a + 1b (0.26%). Genotype distribution varies according to geographical regions. However, genotype 1 (82.92%) was the most common genotype in all regions and all years. This was followed by genotype 3 (7.07%) and genotype 4 (5.43%). A variety of methods were used by the centers including sequencing, pyrosequencing, real-time PCR, in-house RFLP, reverse hybridization (LIPA), and hybridization., Conclusions: Infection with mixed HCV genotypes in Turkey is uncommon. Genotype distribution varies according to geographic regions; the most common genotype 1 is encountered all over the country, while genotypes 3 and 4 are only in some of the centers. Since there is limited information about mixed HCV infection, further investigations are needed to determine the clinical importance of mixed HCV infection.

Although Salmonella enterica serotype Paratyphi B is the less frequently isolated serotype worldwide and in Turkey, it is the most common serotype in our hospital, with a marked increase in 2007. The purpose of this study was to investigate the antibiotic susceptibility and the extended spectrum beta-lactamase (ESBL) profile, and molecular epidemiology of S. Paratyphi B isolates detected in our hospital microbiology laboratory. Seventy isolates identified as S. Paratyphi B from 109 Salmonella isolates obtained from clinical specimens from different patients between October 2005 and December 2012, were included in the study. In addition to conventional methods, isolates were identified using the Phoenix automated microbiology system (Becton Dickinson, USA). Serotyping of the isolates was performed on the basis of slide agglutination and the Kauffmann-White scheme. The antibiotic susceptibility of the isolates was determined using the BD Phoenix' automated system and disk diffusion test. ESBL enzymes were investigated using the combined disk test, isoelectric focusing, polymerase chain reaction (PCR) and sequence analysis. The molecular epidemiology of the 51 isolates obtained between October 2005 and August 2008 was examined with pulsed-field gel electrophoresis (PFGE) using the XbaI enzyme. S. Paratyphi B isolates were obtained from 70 specimens (46 blood, 16 fecal, 4 bone marrow, 2 urine and 2 wound) each from different patients. Resistance to nalidixic acid was determined in 18.6%, resistance to ampicillin, cefotaxime and cefepime in 2.9% and to ceftazidime and co-trimoxazole in 1.4% of the isolates. ESBL production was detected only in two isolates; in one TEM-1 was accompanied by CTX-M-15 and in the other isolate CTX-M-3 was found. Forty-six of the 51 isolates (90%) were found to be genetically related by PFGE and were placed in cluster A. The distribution of the isolates in cluster A revealed six subtypes as A1 (n= 7), A2 (n= 11), A3 (n= 7), A4 (n= 18), A5 (n= 2) and A6 (n= 1). Three different patterns not related to the cluster A were determined in the remaining five isolates (two were B, one of each was C, D and E). In conclusion, although the rate of antibiotic resistance was low in the S. Paratyphi B isolates in our hospital, rare types of ESBLs such as CTX-M-3 and CTX-M-15 were detected in Salmonellae. As far as the current literature is considered, this is the first report in Turkey of blaCTX-M-15 in Salmonella spp. and blaCTX-M-3 genes in S. Paratyphi B. The results may indicate a possible future threat to the treatment of Salmonella infections. Since most of the isolates were genetically related, this might suggest an epidemic in our region.

Objective: To determine the hepatitis B virus (HBV) genotypes and subgenotypes in patients with HBV infection in the Eastern Black Sea region of Turkey., Methods: One hundred and thirty-seven patients' samples collected over 5 years (January 2005 to January 2010) at Farabi Hospital in Karadeniz Technical University, Trabzon, Turkey were included in the study. All patients were positive for hepatitis B surface antigen (HBsAg) and HBV DNA. The HBV genotypes were determined by the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method using an amplified segment of the pre-S region of HBV., Results: One hundred and twenty-five of the 137 HBV samples (91.3%) were identified as genotype D using the PCR-RFLP method. Twelve isolates had undefined patterns, 122 of the 125 samples (97.6%) were determined as subgenotype D2, 2 (1.6%) were subgenotype D1, and one (0.8%) was subgenotype D-del., Conclusion: Similar findings in the other parts of the Turkey, the predominant patterns of HBV prevailing among patients in the Eastern Black Sea region of Turkey were of genotype D and subgenotype D2.

This study presents data on species distribution and antifungal susceptibility profiles of Candida bloodstream isolates obtained from a Turkish Tertiary Care Hospital during a 4-year period. All hospitalized patients who had ≥ 1 blood culture positive for yeast during their hospital stay from January 2005 through 2009 were included in this study. All isolates were identified to species level using CHROMagar and ID 32 C. Fluconazole and voriconazole antifungal susceptibility testing was performed using the disk diffusion method according to CLSI M44-A. In vitro activity of amphotericin B was determined by the Etest. Of all 166 yeast isolates, C. albicans was the dominant species (34.3%), followed by Candida parapsilosis (28.9%) and C. tropicalis (8.4%). All of the 48 C. parapsilosis strains were identified as C. parapsilosis sensu stricto. Resistance to fluconazole was more common among C. krusei isolates. Voriconazole resistance was absent. One C. lusitaniae strain showed a high amphotericin MIC (4 μg/ml). Our survey indicated an increase of some non-C. albicans Candida species in our hospital while antifungal resistance was uncommon.

The aim of this study was to estimate the prevalence and predictors of Chlamydia trachomatis infection among young adult low-risk women attending either of two inner-city family planning clinics in Trabzon, the most densely populated city in Turkey's Black Sea region. The study group comprised 150 sexually active women attending either of two family planning clinics. Two endocervical swabs were collected from each woman and tested for the presence of C. trachomatis by tissue culture and a commercially available enzyme immunoassay (ELISA). Multivariable logistic regression analysis was used to identify the associations of clinical factors for predicting C. trachomatis infection. C. trachomatis was detected in 19 of the samples (12.7%) by cell culture and in 15 (9.9%) by ELISA. None of the demographic characteristics could be associated with the state of infection, but the women preferring the withdrawal method for contraception accounted for a significantly higher percentage of the C. trachomatis-positive cases than women who used other contraceptive methods. The most frequent signs of cervical infection were vaginal discharge (RR = 4.86, 95% CI 1.60 and 14.79, P = 0.005) and cervical erosion (RR = 3.26, 95% CI 0.97 and 10.90, P = 0.056).

The Eastern Black Sea Region has an extensive flora because of ample rainfall lasting all year. In this study, antimicrobial effects of 74 crude extracts of 22 endemic plants were investigated. Among the 30 active crude extracts, water-insoluble crude extracts from Betula medwediewii, Heracleum platytaenium, Primula longipes, Anthemis cretica ssp. argaea and Centaurea helenioides were the prominent ones with their MIC values.

Objective: The rapid, simple and non-invasive diagnosis of Helicobacter pylori (H. pylori) infection is important in implementing chemotherapy in appropriate manner, and in assessing persistent H. pylori infection after eradication therapy. The ImmunoCard STAT! HpSA kit (Meridian Bioscience, Europe) is a lateral flow chromatography test which utilizes a monoclonal anti-H. pylori antibody. In this study, we investigated the usefulness of the ImmunoCard STAT! HpSA test before and after eradication therapy on patients referred to undergo upper gastrointestinal endoscopy., Methods: Sixty-five consecutive patients who were referred to undergo upper gastrointestinal endoscopy at the Department of Gastroenterology, Karadeniz Technical University Medical School, Turkey between February and August 2005 were included in this study. The ImmunoCard STAT! HpSA was compared with 4 invasive tests (histology, gram staining, rapid urease test, and culture). The reference method was defined as positive when 2 of the 4 invasive tests were positive. A negative H. pylori status was considered when all 4 tests present concordant negative results., Results: Overall, the ImmunoCard STAT! HpSA test had 77.8% sensitivity, 79.3% specificity, 82.4% positive predictive value (PPV) and 74.2% negative predictive value (NPV) in all patients. With regard to pre-treatment values, the sensitivity was 70.6%, specificity 70.6%, PPV 100% and NPV 100% while on post-treatment group the sensitivity was 84.2%, specificity 64.7%, PPV 72.7% and NPV 78.6%., Conclusion: Our results indicate that the ImmunoCard STAT! HpSA test is a rapid, simple, and helpful procedure not only to determine H. pylori infection but also to assess the success of eradication therapy.

Twenty-three rifampicin-resistant methicillin-resistant Staphylococcus aureus (MRSA) isolated in three wards at a university hospital in Turkey between June, 2000, and February, 2001, were studied for their genetic relatedness using a combination of antibiogram, coagulase serotyping, coagulase gene polymorphism (coa-RFLP), and pulsed-field gel electrophoresis (PFGE). They all expressed high-level rifampicin resistance (MIC, >256 mg/L) and were resistant to gentamicin, kanamycin, amikacin, ciprofloxacin, tetracycline, and cadmium acetate and were susceptible to fusidic acid, vancomycin, trimethoprim, and mupirocin. They belonged to the same coagulase serotype (serotype IV) and had identical coa-RFLP patterns. In contrast, PFGE generated nine banding patterns designated type A, types A1-A5, B, C, and D. The most common PFGE pattern (type A) and its subtypes (types A1-A5) were seen in 20 (87%) of the 23 isolates in the three wards. The results demonstrated the acquisition of rifampicin resistance by different MRSA clones and the spread of one clone among patients in the three wards.

The aim of this investigation was to evaluate the epidemiology of Stenotrophomonas maltophilia in a university hospital of Turkey. From June 2000 to December 2001, S. maltophilia strains were collected, clinical presentations were noted, and MIC determinations were performed by means of E-test. Enterobacterial repetitive intergenic consensus sequences-PCR (ERIC-PCR) was used for molecular typing of the strains. Forty-four strains of S. maltophilia were isolated from 41 hospitalized patients in a teaching hospital. The majority of specimens were from the blood and respiratory tract. Antimicrobial sensitivities of these strains were as follows: 97.7 % trimethoprim-sulfamethoxazole, 15.9% ticarcillin, and 95.4% ticarcillin- clavulanate. The strains were evaluated using the ERIC-PCR method. It was of interest to note that epidemiological typing revealed three small outbreaks that were caused by a total of 12 strains. The remaining isolates generated singular DNA patterns. DNA amplification was possible in 38 isolates and yielded 26 different patterns in a period of 20 months, leading to the suggestion that commensal bacteria becomes selected in the presence of a suitable host.

Transfusion of blood and blood products is a widely used method for therapy in medicine, however it may result with the transmission of infectious agents from donor to recipient. In order to achieve safe blood transfusions and to minimize post-transfusion infections, several screening tests for infectious agents are routinely done all around the world as well as in our country. In this study, HBsAg, anti-HCV, anti-HIV and syphilis reagin antibody tests results have been retrospectively evaluated for 33.766 blood donors during January 1, 1997 to December 31, 2000 in Blood Center of Farabi Hospital, Black Sea Technical University. Testing for HBsAg, anti-HIV and anti-HCV has been done by using commercially available micro and/or macro enzyme immunoassays, and syphilis reagin antibody test by latex agglutination (RPR) method. The indeterminate results were confirmed by retesting of sera with microparticle enzyme immunoassay and Western blot methods. As a result, in 1331 (3.94%) subjects HBsAg, in 250 (0.74%) subjects anti-HCV, and in 161 (0.47%) subjects RPR were found positive. Twenty samples which have had the results in gray-zone for anti-HIV, have been found negative with the confirmation tests.