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In this study, microbial community dynamics were assessed in two lab-scale anaerobic sequencing batch reactors (ASBRs). One of the reactors was fed by synthetic pharmaceutical industry wastewater with sulfamethoxazole (SMX) as the test reactor and the other without sulfamethoxazole as the control reactor. DNA based DGGE results indicated that Clostiridum sp. became dominant in the SMX reactor while the inoculum was dominated with Firmicutes (61%) and Methanomicrobiales (28%). However their abundances in active community decreased through the last phase. Also the abundance of hydrogenotrophs was high in each phase, while acetoclastic methanogens disappeared in the last phase. Q-PCR analysis revealed that there is a significant reduction in the bacterial community approximately 84%, while methanogens increased to 97% through the operation. Additionally an increase in the expression level of bacterial and methanogenic 16S rRNA (60% and 20%, respectively) was detected. Significant correlation between microbial community and the reactor operation data was found. The study demonstrated that the microbial community maintains the system stability under high antibiotic concentration and long-term operation by homoacetogenesis coupled with hydrogenotrophic methanogenesis . [ABSTRACT FROM AUTHOR]

The study explored the acute inhibitory impact of erythromycin on the methanogenic activity of acclimated biomass fed with a volatile fatty acid mixture and acetate alone. Parallel batch reactors were operated for six days, with increasing erythromycin dosing in the range of 1–1000 mg L −1 . Substrate removal was monitored by means of soluble COD and volatile fatty acid (VFA) measurements together with parallel observations on biogas and methane generation. The inhibitory impact was variable with the initial erythromycin dose: At lower doses, the VFA mixture was completely removed but partially utilized, leading to reduced biogas and methane generation, suggesting the analogy of uncompetitive inhibition. At higher doses, propionate utilization was totally impaired and butyrate removal was reduced, but acetate was still fully removed. Remaining VFAs were partly converted to new VFA compound through isomerization and polymerization reactions. High erythromycin doses induced total inactivation of microbial metabolism with negligible methane generation. [ABSTRACT FROM AUTHOR]

This study evaluates the joint effects of erythromycin-sulfamethoxazole (ES) combinations on anaerobic treatment efficiency and the potential for antibiotic degradation during anaerobic sequencing batch reactor operation. The experiments involved two identical anaerobic sequencing batch reactors. One reactor, as control unit, was fed with synthetic wastewater while the other reactor (ES) was fed with a synthetic substrate mixture including ES antibiotic combinations. The influence of ES antibiotic mixtures on chemical oxygen demand (COD) removal, volatile fatty acid production, antibiotic degradation, biogas production, and composition were investigated. The influent antibiotic concentration was gradually increased over 10 stages, until the metabolic collapse of the reactors, which occurred at 360 days for the ES reactor. The results suggest that substrate/ COD utilization and biogas/methane generation affect performance of the anaerobic reactors at higher concentration. In addition, an average of 40% erythromycin and 37% sulfamethoxazole reduction was achieved in the ES reactor. These results indicated that these antibiotics were partly biodegradable in the anaerobic reactor system. [ABSTRACT FROM AUTHOR]

Abstract: Undecomposed human bodies and organs always attracted interest in terms of understanding biological tissue stability and immortality. Amongst these, cases of natural mummification found in glaciers, bog sediments and deserts caused even more attention. In 2010, an archeological excavation of a Bronze Age layer in a tumulus near the Western Anatolia city Kütahya revealed fire affected regions with burnt human skeletons and charred wooden objects. Inside of the cracked skulls, undecomposed brains were discernible. To analyze the burial taphonomy of the rare phenomenon of brain preservation, we analyzed brains, bone, teeth and surrounding soils elements using Inductively Coupled Plasma-Mass Spectrometer (ICP-MS). Adipocere formation or saponification of postmortem tissue fat requires high levels of alkalinity and especially potassium. Indeed, ICP-MS analysis of the brain, teeth and bone and also of the surrounding soil revealed high levels of potassium, magnesium, aluminum and boron, which are compatible with the famous role of Kütahya in tile production with its soil containing high level of alkalines and tile-glazing boron. Fatty acid chromatography revealed simultaneous saturation of fats and protection of fragile unsaturated fatty acids consistent with soil-presence of both pro-oxidant and anti-oxidant trace metals. Computerized tomography revealed protection of diencephalic, metencephalic and occipital tissue in one of the best-preserved specimens. Boron was previously found as an intentional preservative of Tutankhamen and Deir el Bahari mummies. Here, in natural soil with its insect-repellant, anti-bacterial and fire-resistance qualities it may be a factor to preserve heat-affected brains as almost bioporcellain specimens. [Copyright &y& Elsevier]

Abstract: The study evaluates the chronic impact of the antibiotic tetracycline on the biodegradation of organic substrate under anaerobic conditions. The experiments involved an anaerobic sequencing batch reactor fed with a synthetic substrate mixture including glucose, starch and volatile fatty acids, and operated in a sequence of different phases with gradually increasing tetracycline doses of 1.65–8.5 mg/L, for more than five months. Tetracycline exerted a terminal/lethal effect at 8.5 mg/L on the microbial community under anaerobic conditions, which caused the inhibition of substrate/COD utilization and biogas generation and leading to a total collapse of the reactor. The microbial activity could not be recovered and re-started within a period of more than 10 days, even after stopping tetracycline dosing. At lower doses, substrate utilization was not affected but a reduction of 10–20% was observed in the biogas/methane generation, suggesting that substrate utilization of tetracycline to the biomass was limiting their bioavailability. During the experiments, tetracycline was partially removed either through biodegradation or conversion into its by-products. The adverse long-term impact was quite variable for fermenting heterotrophic and methanogenic fractions of the microbial community based on changes inflicted on the composition of remaining/residual organic substrate. [Copyright &y& Elsevier]

Objectives – Strokes represent the most common etiology of epilepsy in patients over the age of 60 years, with an incidence of 2–4% occurring in different studies. Materials and Methods – In this observational study, 1,428 patients were included who had stroke and were admitted to our Stroke Unit between the years 1996 and 2005. Results – Overall, 51 patients had post-stroke epilepsy (3.6%). Post-ischemic epilepsy occurred in 70.6% of the patients, post-hemorrhagic epilepsy occurred in 21.6% of the patients and epilepsy following venous infarctions occurred in 7.8% of all post-stroke epilepsy patients. Of 1,327 patients having ischemic stroke, 36 patients (2.7%), 11 out of 86 patients with hemorrhagic stroke (12.8%) and 4 of 15 patients with venous infarctions (26.6%) developed epilepsy. Compared with stroke patients without epilepsy, hemorrhagic ( P < 0.001) and venous infarctions were more common in patients with post-stroke epilepsy ( P < 0.001). The right hemisphere and the middle cerebral artery (MCA) territory were most commonly observed in ischemic and hemorrhagic stroke patients. Conclusions – Our results indicate that post-stroke epilepsy is more common among patients who have experienced venous infarctions. Hemorrhagic and venous infarctions are more commonly encountered in post-stroke epilepsy patients. Atherosclerotic and cardioembolic strokes were similar to those that occurred in post-stroke epilepsy patients. Localizations in post-stroke epileptic patients showed that the majority occurred in the right hemisphere, in the territory of the MCA. However, prospective, multicentered studies are needed for a better understanding of the epidemiology and social impact of post-stroke epilepsy. [ABSTRACT FROM AUTHOR]

Introduction: Electrocardiographic (ECG) changes are observed in patients with acute stroke and are related with the prognosis. Aims: To determine the frequency and significance of ECG changes in patients with acute ischemic stroke. Material and Methods: In a prospective hospital-based study 87 patients with cerebral infarction were observed for ECG changes during their stay in the hospital. All the patients had ischemic stroke for the first time. The ECG changes observed were compared with those of the control group consisting of 87 patients. Results: Of the 87 patients of the study group, 47.1% were females and 52.9% males. The mean age was 65.5 ± 11.9. (range 31-91 yrs). The control group consisted of 50.6% females and 49.4% males. The mean age was 64.5 ± 9.1 (range 31-87 yrs). The frequency of the ECG changes observed in patients with cerebral infarct was 62.1% while it was 29.9% in the control group (P<0.0001). ECG changes observed were mostly related to myocardial ischemia. The six-month mortality rate in the patients with ECG changes was 38.9% whereas it was 15.2% in those with normal ECG (P<0.05). Conclusions: The observations of this study suggest that cardiac evaluation in patients with acute ischemic stroke is of prognostic importance. [ABSTRACT FROM AUTHOR]

Abstract: Aims: To investigate the effects of different bioaugmentation strategies for enhancing the biogas production from cow manure and evaluate microbial community patterns. Methods and Results: Co‐inoculation with cow rumen fluid and cow rumen‐derived enriched microbial consortia was evaluated in anaerobic batch tests at 36°C and 41°C. Singular addition of both rumen fluid and enriched bioaugmentation culture had a promising enhancement on methane yields; however, the highest methane yield (311 ml CH4 per gram VS at 41°C) was achieved when the anaerobic seed sludge was co‐inoculated together with rumen fluid and enriched bioaugmentation culture. Bacterial community profiles were investigated by Ion PGM Platform, and specific lignocellulolytic bacteria dynamics in batch tests were assessed by qPCR. The temperature had minor effects on the abundance of bacterial community; in which Bacteroidetes and Firmicutes were the most abundant phyla in all digesters. Furthermore, Rikenellaceae, Clostridiaceae, Porphyromonadaceae, Bacteroidaceae and Ruminococcaceae played a crucial role during the anaerobic degradation of cow manure. There was an important impact of Firmicutes flavefaciens and Ruminococcus albus at 41°C, which in turn positively affected the methane production. Conclusion: The degree of enhancement in biogas production can be upgraded by the co‐inoculation of rumen‐derived bioaugmentation culture with anaerobic seed sludge with high methanogenic activity. Significance and Impact of the Study: A close look at the biotic interactions and their associations with abiotic factors might be valuable for evaluating rumen‐related bioaugmentation applications. [ABSTRACT FROM AUTHOR]

Attachment, strength and performance of a porous media in an upflow anaerobic filter (UFAF) treating dairy wastewater were investigated. Microscopic examination showed that the number of autofluorescent methanogens varied 15-28% of the number of total bacteria along the UFAFwhile the number of viable methanogens was 10-70 times less that of autofluorescent methanogens. The most dominant species was found to be Methanococcus followed by short rods, medium rods, long rods, filaments and Methanosarcina. The quantity of attached biomass was the highest at the bottom, 103 mg VSS/media ring and lowest at the top, 23 mg VSS/media ring and an average of 55 mg VSS/media ring in the mid-height inside the UFAF. An average of 50% reduction in compressive strength of the sintered glass media after 8 months of operation was measured. The UFAF was operated up to an organic loading rate of 21 kg COD/m3.d with a hydraulic retention time of 0.5 day and an average of 80% COD removal efficiency for most of the operating periodwas achieved. [ABSTRACT FROM AUTHOR]

A full-scale upflow anaerobic sludge blanket (UASB) reactor was investigated in terms of archaeal composition, acetoclastic methanogenic capacity and performance over a 2-year period. Performance of the reactor in terms of COD removal efficiency varied between 60% and 80% at organic loading rates (OLRs) in the range of 2.5-12 kg COD m-3d-1. The reactor had been operated under a F/M (food to microorganisms) ratio of 0.02-0.03 gCOD gTVS-1 d-1, which is much lower than the typical values reported for similar reactors. According to specific methanogenic activity (SMA) tests the anaerobic sludge was operating at only 12-34% of its potential acetoclastic methanogenic capacity. These results demonstrated that the UASB reactor was under loaded compared to its maximum loading capacity. All other operational parameters had been maintained within their desired ranges. The SMA test and Fluorescence in situ hybridization (FISH) results revealed that a decrease in the acetoclastic methanogenic activity of the UASB sludge from 344 mL CH4 gTVS-1 d-1 to 109 mL CH4 gTVS-1 d-1coincided with a decrease in the relative abundance of acetoclastic Methanosaeta from 90% ± 1.2 to 79% ± 1.4 of the archaeal population, and an increase in the relative abundance of hydrogenotrophic Methanobacteriales from non-detectable levels to 24% ± 0.7% of the archaeal population during the 2-year operation of the reactor. The relative abundance of archaeal cells within the UASB sludge was in the range of 15-17%. [ABSTRACT FROM AUTHOR]

In this study, two laboratory-scale anaerobic batch reactors started up with different inoculum sludges and fed with the same synthetic wastewater were monitored in terms of performance and microbial community shift by denaturant gradient gel electrophoresis fingerprinting and subsequent cloning, sequencing analysis in order to reveal importance of initial quality of inoculum sludge for operation of anaerobic reactors. For this purpose, two different seed sludge were evaluated. In Reactor1 seeded with a sludge having less diverse microbial community (19 operational taxonomic unit (OTU's) for Bacterial and 8 OTU's for Archaeal community, respectively) and a methanogenic activity of 150 ml CH g TVS day, a chemical oxygen demand (COD) removal efficiency of 78.8 ± 4.17% was obtained at a substrate to microorganism (S/X) ratio of 0.38. On the other hand, Reactor2, seeded with a sludge having a much more diverse microbial community (24 OTU's for Bacterial and 9 OTU's for Archaeal communities, respectively) and a methanogenic activity, 450 ml CH g TVS day, operated in the same conditions showed a better start-up performance; a COD removal efficiency of over 98% at a S/X ratio of 0.53. Sequence analysis of Seed2 revealed the presence of diverse fermentative and syntrophic bacteria, whereas excised bands of Seed1 related to fermentative and sulfate/metal-reducing bacteria. This study revealed that a higher degree of bacterial diversity, especially the presence of syntrophic bacteria besides the abundance of key species such as methanogenic Archaea may play an important role in the performance of anaerobic reactors during the start-up period. [ABSTRACT FROM AUTHOR]

In this study, specific methanogenic activity (SMA) test and fluorescence In situ hybridisation (FISH) were respectively used to determine acetoclastic methanogenic capacity, and composition and number of methanogenic and sulphate reducing bacterial (SRB) populations within a full scale anaerobic contact reactor treating a pulp and paper industry effluent. The sludge samples were collected from three different heights along the anaerobic reactor having a difficulty of completely stirring. Performance of the anaerobic reactor in terms of COD removal efficiency varied between 47 and 55% at organic loading rates in a range of 1.6 - 1.8 kg COD m-3d-1 and methane yield varied between 0.18 and 0.20m³CH4kg CODrem-1. The anaerobic reactor was not operated for 2 weeks during the monitoring period. According to SMA test results, potential methane production rate was 276 mL CH4 gVSS-1d-1 before the off period of the reactor, however it decreased to 159 mL CH4 gVSS-1d-1 after this period. SMA test and FISH results along the reactor height showed that the acetoclastic methanogenic activity of the sludge samples, the relative abundance of acetoclastic methanogens, hydrogenotrophic methanogens and acetate oxidising SRB decreased as the reactor height increased, however the relative abundance of non-acetate oxidising SRB increased. [ABSTRACT FROM AUTHOR]

Abstract: We report a study of the impact of cold crystallization on the structure of nanocomposites comprising poly(vinylidene fluoride) (PVDF) and Lucentite STN™ organically modified silicate (OMS). Nanocomposites were prepared from solution over a very wide composition range, from 0.01 to 20% OMS by weight. Thermal preparation involved cold crystallization at 145°C of quenched, compression-molded plaques. Static and real-time wide and small angle X-ray scattering (WAXS, SAXS), Fourier transform infrared spectroscopy (FTIR), and differential scanning calorimetry (DSC) were used to investigate the crystalline phase of PVDF. For OMS content greater than 0.50wt%, WAXS studies show that that the silicate gallery spacing increases modestly in the nanocomposites compared to neat OMS film, indicating a level of polymer intercalation. Using Gaussian peak fitting of WAXS profiles, we determine that the composition range can be divided into three parts. First, for OMS greater than 0.5wt%, alpha phase fraction, ϕ alpha, is insignificant (ϕ alpha∼0–0.01). Second, at the intermediate range, for OMS between 0.5wt% down to 0.025wt%, beta phase dominates and the beta fraction, ϕ beta, is related to alpha by ϕ beta>ϕ alpha. Third, below 0.025wt% OMS, alpha dominates and ϕ alpha>ϕ beta. The ability of small amounts of OMS (≥0.025wt%) to cause beta crystal domination is remarkable. Overall, crystallinity index (from the ratio of WAXS crystal peak area to total area) ranges from about 0.36 to 0.51 after cold crystallization. Real-time WAXS studies during heating of initially cold crystallized nanocomposites show that there is no inter-conversion between the alpha and beta phase PVDF crystals, where these crystals coexist at room temperature. While all samples showed a strong SAXS Bragg peak, indicating existence of two-phase lamellar stacks, the sample containing predominantly beta phase had poorly correlated lamellar stacks, compared to samples containing predominantly alpha phase. [Copyright &y& Elsevier]

Introduction: Although history of childhood trauma is present in nearly 50% of bipolar patients, the effects of childhood trauma on the course of bipolar disorder are rarely investigated. Thus, we aimed to investigate the effects of childhood trauma on psychotic symptoms seen in patients with bipolar disorder. Methods: One-hundred DSM-IV-TR diagnosed bipolar patients who were either manic or depressive were recruited from inpatient units of Bakirkoy Research and Training Hospital for Psychiatry, Neurology and Neurosurgery. Patients were initially evaluated by Young Mania Rating Scale (YMRS), Montgomery-Asperg Depression Rating Scale (MADRS), Scales for Assessment of Positive Symptoms. Patients were also evaluated by Childhood Trauma Questionnaire (CTQ) and Dissociative Experiences Scale in euthymia which was defined by scores of <7 in YMRS, <4 in MADRAS Results: There were no differences between the patients with and without a history of psychotic episode in terms of age at onset, duration of illness and episode characteristics. Patients with a history of psychotic episode were hospitalized more. CTQ physical abuse scores were higher in male comparing to female. CTQ sexual abuse scores were higher in female comparing to male. CTQ emotional abuse, physical neglect, physical abuse and total scores were higher in patients who had at least one psychotic episode in lifetime than in patients without a history of psychotic episode. Conclusion: The history of childhood trauma should be investigated and therapeutic interventions for childhood trauma should be added to the standard treatment plan of bipolar patients. [ABSTRACT FROM AUTHOR]