Investigation of pilot scale manufacturing of polysulfone (PSf) membranes by wet phase inversion method

Membranes are used as a support layer for the fabrication of thin film composite membranes. Sup- port layer properties can affect many performance parameters of TFC membranes such as flux, rejection, morphology and stability against pressure. Although studies in lab scale fabrication exist, investigation the pilot scale polysulfone membrane fabrication has not been done. In this study, opti- mization of polysulfone support membranes fabrication was conducted in pilot scale. Coagulation bath temperature; casting speed and solution content were selected as main parameters for the opti- mization. Membrane surface properties were investigated in details with SEM and pore size dis- tribution. Membrane performance were determined with permeability experiments. Differences in pilot scale and lab scale membrane manufacturing were observed and compared with literature. On the contrary to literature it was found that, coagulation bath temperature has exact opposite effect in pilot scale membrane formation compared to lab scale studies. 10°C drop (from 25°C to 15°C) in coagulation bath temperature decreased mean pore size of membranes from 27 nm to 8 nm and per- meability from 464 l/m2h to 100 l/m2h while everything else was kept constant

"Türkiye ve Pakistan yerli koyun ırklarında prion protein geni polimorfizmleri taranması"

TÜBİTAK TOVAG01.01.2012Koyun ve keçilerin inkübasyon süresi uzun, ölümcül, merkezi sinir sistemini etkileyen (nörodejeneratif) bir hastalığı olan skrapi; birçok memeli türünü etkileyen bulaşıcı süngerimsi ensefalopatilerden (Transmissible Spongyform Encephalopathy -TSE) yani prion protein hastalıklarından biridir. Koyunda üç ekzon ve iki introndan oluşan prion protein geninde üçüncü ekzon bölgesinde halen 50’den fazla nokta mutasyonu polimorfizmi (TNP) gözlenmiştir. Ancak, skrapiye direnç / hassasiyeti belirleyen prion protein gen bölgesindeki mutasyonların 136, 141, 154 ve 171. kodonlarına dayalı genotiplerin olduğu bildirilmektedir. Avrupa-Asya yelpazesinde birikmiş verilerin çoğunlukla Avrupa’dan olduğu dikkat çekicidir. Halbuki arkeolojik ve genetik veriler Orta Doğu’nun koyun evcilleştirme merkezi olduğunu göstermektedir. Ancak, yapılan çalışmalar incelendiğinde bu bölgeden verilerin daha sınırlı olduğu görülmektedir. Bu çalışmada, skrapi vakasının rapor edilmediği Türkiye yerli koyun ırklarında prion protein gen polimorfizminin 15 farklı populasyonda incelemesi yapılmıştır. Çalışmada prion protein gen bölgesinin 3’üncü ekzon bölgesine ait 745 bç (baz çifti) uzunluğundaki bölgesi 655 bireyde sekanslanarak çalışılmıştır. Elde edilen veriler, Türkiye’de skrapiyi önlemeden sorumlu otoriteler, hayvan yetiştirme birlikleri ve üniversitelerin araştırma birimlerince kullanılması açısından yararlıdır. Ayrıca veriler, Dünya’daki PrP protein polimorfizm verilerinin coğrafi dağılımındaki büyük boşluğu önemli ölçüde doldurmuştur. Çalışmada elde edilen detaylı veriler fonksiyonu tam olarak bilinmeyen PrP protein bölgesinin hangi evrimsel güçler etkisinde olabileceği ile ilgili bilgilere katkılarda bulunmaktadır.Scrapie is an infectious fatal disease of sheep and it is a member of Transmissible Spongiform Encephalopathies (TSE) (or a prion disease) and affects the central nervous system. Susceptibility to scrapie is associated with polymorphisms in sheep prion protein (PrP) gene, based on their genotypes at codons 136, 141, 154 and 171. In Europe-Asia spectrum, accumulated data is mostly from Europe. Whereas, archeological and genetic evidences indicated that Middle East is the heart of sheep domestication and all of the sheep breeds must have went out from this region. Yet, data from this region is preliminary. The main purpose of the study is to collect an extensive data,covering 14 breeds 15 different populations represented by 655 individuals where each of which are sequenced for 745 base pairs of PrP 3rd exon region. It will be a data where individuals were from Turkey from which scrapie incidence was not reported. This data is important and useful for the authorities responsible from the risk management of scrapie in Turkey, for animal breeders association and for research units of universities. At the same time, it will, considerably, fill the big gap which is present in the data of geographic distribution of PrP polymorphisms in the world. The detailed data obtained by the study will contribute to the understanding of evolutionary mechanisms operating on the PrP gene of which the function is unknown

Intrabiliary rupture of liver hydatid cyst: a case report and review of the literature

Herein, we report a 66 year old woman who was diagnosed to have intrabiliary rupture of liver hydatid cyst with demonstrative computed tomography, magnetic resonance imaging, and magnetic resonance cholangiopancreatography findings, with a review of the literature

Multifunctional 3D printing of heterogeneous hydrogel structures

Multimaterial additive manufacturing or three-dimensional (3D) printing of hydrogel structures provides the opportunity to engineer geometrically dependent functionalities. However, current fabrication methods are mostly limited to one type of material or only provide one type of functionality. In this paper, we report a novel method of multimaterial deposition of hydrogel structures based on an aspiration-on-demand protocol, in which the constitutive multimaterial segments of extruded filaments were first assembled in liquid state by sequential aspiration of inks into a glass capillary, followed by in situ gel formation. We printed different patterned objects with varying chemical, electrical, mechanical, and biological properties by tuning process and material related parameters, to demonstrate the abilities of this method in producing heterogeneous and multi-functional hydrogel structures. Our results show the potential of proposed method in producing heterogeneous objects with spatially controlled functionalities while preserving structural integrity at the switching interface between different segments. We anticipate that this method would introduce new opportunities in multimaterial additive manufacturing of hydrogels for diverse applications such as biosensors, flexible electronics, tissue engineering and organ printing

Association of uric acid levels before start of conditioning with mortality after allogeneic hematopoietic stem cell transplantation - a prospective, non-interventional study of the EBMT Transplant Complication Working Party

Uric acid is a danger signal contributing to inflammation. Its relevance to allogeneic stem cell transplantation (alloSCT) derives from preclinical models where the depletion of uric acid led to improved survival and reduced graft-versus-host disease (GvHD). In a clinical pilot trial, peri-transplant uric acid depletion reduced acute GvHD incidence. This prospective international multicenter study aimed to investigate the association of uric acid serum levels before start of conditioning with alloSCT outcome. We included patients with acute leukemia, lymphoma or myelodysplastic syndrome receiving a first matched sibling alloSCT from peripheral blood, regardless of conditioning. We compared outcomes between patients with high and low uric acid levels with univariate- and multivariate analysis using a cause-specific Cox model. Twenty centers from 10 countries reported data on 366 alloSCT recipients. There were no significant differences in terms of baseline co-morbidity and disease stage between the high- and low uric acid group. Patients with uric acid levels above median measured before start of conditioning did not significantly differ from the remaining in terms of acute GvHD grades II-IV incidence (Hazard ratio [HR] 1.5, 95% Confidence interval [CI]: 1.0-2.4, P=0.08). However, they had significantly shorter overall survival (HR 2.8, 95% CI: 1.7-4.7, PPeer reviewe

Comparative analysis of different laser systems to study cellular responses to DNA damage in mammalian cells

Proper recognition and repair of DNA damage is critical for the cell to protect its genomic integrity. Laser microirradiation ranging in wavelength from ultraviolet A (UVA) to near-infrared (NIR) can be used to induce damage in a defined region in the cell nucleus, representing an innovative technology to effectively analyze the in vivo DNA double-strand break (DSB) damage recognition process in mammalian cells. However, the damage-inducing characteristics of the different laser systems have not been fully investigated. Here we compare the nanosecond nitrogen 337 nm UVA laser with and without bromodeoxyuridine (BrdU), the nanosecond and picosecond 532 nm green second-harmonic Nd:YAG, and the femtosecond NIR 800 nm Ti:sapphire laser with regard to the type(s) of damage and corresponding cellular responses. Crosslinking damage (without significant nucleotide excision repair factor recruitment) and single-strand breaks (with corresponding repair factor recruitment) were common among all three wavelengths. Interestingly, UVA without BrdU uniquely produced base damage and aberrant DSB responses. Furthermore, the total energy required for the threshold H2AX phosphorylation induction was found to vary between the individual laser systems. The results indicate the involvement of different damage mechanisms dictated by wavelength and pulse duration. The advantages and disadvantages of each system are discussed

New Functions of Ctf18-RFC in Preserving Genome Stability outside Its Role in Sister Chromatid Cohesion

Expansion of DNA trinucleotide repeats causes at least 15 hereditary neurological diseases, and these repeats also undergo contraction and fragility. Current models to explain this genetic instability invoke erroneous DNA repair or aberrant replication. Here we show that CAG/CTG tracts are stabilized in Saccharomyces cerevisiae by the alternative clamp loader/unloader Ctf18-Dcc1-Ctf8-RFC complex (Ctf18-RFC). Mutants in Ctf18-RFC increased all three forms of triplet repeat instability—expansions, contractions, and fragility—with effect over a wide range of allele lengths from 20–155 repeats. Ctf18-RFC predominated among the three alternative clamp loaders, with mutants in Elg1-RFC or Rad24-RFC having less effect on trinucleotide repeats. Surprisingly, chl1, scc1-73, or scc2-4 mutants defective in sister chromatid cohesion (SCC) did not increase instability, suggesting that Ctf18-RFC protects triplet repeats independently of SCC. Instead, three results suggest novel roles for Ctf18-RFC in facilitating genomic stability. First, genetic instability in mutants of Ctf18-RFC was exacerbated by simultaneous deletion of the fork stabilizer Mrc1, but suppressed by deletion of the repair protein Rad52. Second, single-cell analysis showed that mutants in Ctf18-RFC had a slowed S phase and a striking G2/M accumulation, often with an abnormal multi-budded morphology. Third, ctf18 cells exhibit increased Rad52 foci in S phase, often persisting into G2, indicative of high levels of DNA damage. The presence of a repeat tract greatly magnified the ctf18 phenotypes. Together these results indicate that Ctf18-RFC has additional important functions in preserving genome stability, besides its role in SCC, which we propose include lesion bypass by replication forks and post-replication repair