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Hydrotreating with dispersed catalyst at ppm level can provide an efficient, economical alternative to upgrading heavy oil. In this study, slurry phase hydro-conversion process is used for viscosity reduction. Several reaction conditions have been investigated using highly dispersed catalyst. Residue conversion of extra-heavy oil up to 30% can meet the viscosity requirement for shipping, and the conversion of bitumen from oil sands up to 50% can meet the viscosity requirement for pipeline systems. These hydrogenation reactions with temperature ranging from 390°C to 420°C had higher liquid yield (from 98.5 wt% to 93.2 wt%). In addition, hydro-upgrading product contains lower concentrations of impurities compared to raw feed. Based on our research, an efficient and environmental friendly alternative upgrading process with low process temperature was proposed. The process uses dispersed catalyst for extra-heavy oil and oil sands bitumen treatment. Product properties meet the requirements for transfer and further application.

Limited water resources restrict winter wheat grain yield and quality in the Huang-Huai-Hai Plain of North China, and establishing optimal planting patterns according to crop water requirements is the key factor for achieving rational water use. In this paper, 4 planting patterns were applied, namely, uniform row (30 cm; traditional pattern), wide (40 cm)-narrow (20 cm) row, furrow (double lines in the furrow with 20 cm spacing, and 40 cm between furrows), and seed bed (double lines on the bed with 20 cm spacing, and 40 cm between beds). Each planting pattern was irrigated twice during the jointing and heading stages, and total irrigation water was controlled at 120 mm. Grain yield was significantly ( LSD, P < 0.05) higher in the furrow planting pattern than in the uniform row, widenarrow row, and seed bed planting patterns, by 73.4, 64.3, and 53.4 g/m 2 , respectively, in 2004–2005 and by 54.3, 42.6, and 30.2 g/m 2 , respectively, in 2005–2006, mainly because of a significant ( LSD, P < 0.05) increase in the spike and kernel numbers. These results were caused by changes in the contribution of dry matter remobilization to grain yield (CDMRG); the CDMRG was higher in the furrow planting pattern than in the uniform row, wide-narrow row, and seed bed planting patterns by 5.1%, 4.3%, and 2.9%, respectively. Gliadin and glutenin contents in the furrow planting pattern were 4.67% and 5.85%, respectively, and were significantly ( LSD, P < 0.05) higher than those in the uniform row, wide-narrow row, and seed bed planting patterns; however, the furrow planting pattern had no significant ( LSD, P < 0.05) effect on albumin and globulin contents. Dough development time (DDT) and dough stable time (DST) in the furrow planting pattern were 5.6 min and 8.8 min, respectively; they were significantly ( LSD, P < 0.05) improved compared to those in the uniform row, wide-narrow row, and seed bed planting patterns; however, there were no significant ( LSD, P < 0.05) differences in dough breakdown time (DBT) between any of the planting patterns. These results suggest that the furrow planting pattern combined with deficit irrigation during the jointing and heading stages can be applied to winter wheat production in the Huang-Huai-Hai Plain of North China.

Sterol regulatory element binding factor 1 (SREBF1) and fatty acid synthase (FASN ) genes play an important role in the biosynthesis of fatty acids and cholesterol, and in lipid metabolism. This study used polymorphisms in the intron 5 of bovine SREBF1 and in the thioesterase (TE) domain of FASN genes to evaluate their associations with beef fatty acid composition. A previously identified 84-bp indel (L: insertion/long type and S: deletion/short type) of the SREBF1 gene in Korean cattle had significant associations with the concentration of stearic (C18:0), linoleic (C18:2) and polyunsaturated fatty acids (PUFA). The stearic acid concentration was 6.30% lower in the SS than the LL genotype (p A, g.18043C>T, g.18440G>A, g.18529G>A and g.18663C>T in the TE domain of the FASN gene were identified among the different cattle breeds studied. Among these, only g.17924 G>A and g.18663C>T SNPs were segregating in the Hanwoo population. The g.17924G>A SNP is a non-synonymous mutation (thr2264ala) and was significantly associated with the contents of palmitic (C16:0) and oleic acid (C18:1). The oleic acid concentration was 3.18% and 2.79% higher in Hanwoo with the GG genotype than the AA and AG genotypes, respectively (p A SNP of the FASN

The high mobility group AT-hook1 (HMGA1) proteins are known to be related to the regulation of gene transcription, replication and promotion of metastatic progression in cancer cells. The loss of expression by disrupting the HMGA1 gene affects insulin signaling and causes diabetes in the mouse. Previously identified single nucleotide polymorphism (SNP) of HMGA1 was significantly associated with fat deposition traits in the pig. In this study, we identified 3,935 bp nucleotide sequences from exon 5 to exon 8 of the bovine HMGA1 gene and its mRNA expression was observed by quantitative real-time PCR. Six single nucleotide polymorphisms in the bovine HMGA1 gene were detected and the allele frequencies of these SNPs were investigated using the PCR- RFLP method in nine cattle breeds including Limousin, Simmental, Brown Swiss, Hereford, Angus, Charolais, Hanwoo, Brahman and Red Chittagong cattle. The map location showed that the bovine HMGA1 gene was also closely located with a previously identified meat quality QTL region indicating this gene is the most likely positional candidate for meat quality traits in cattle. (Key Words: HMGA1, SNP, Meat Quality Traits, Cattle)

Porcine Endogenous Retroviruses (PERVs) are a major concern in relation to xenotransplantation. Previous research indicated that PERVs are present at about 50 copies in the pig genome and their chromosomal insertion sites are different among pig breeds. We examined nine Korean native pigs and seven Asian Wild Boars for the presence of a PERV-A at SSC 1q2.4 and a PERV-B at SSC 7p1.1-2 previously reported in a Large White pig. The PERV-B at locus 7p1.1-2 displayed insertional variability in Korean native pigs and Asian Wild Boars. Using the primers for the PERV-A at 1q2.4 from Large White pig, we only can amplify an unclassified 798 bp sequence, which showed insertional variability only in Korean native pigs. This study indicates that there are differences within and between Asian and European pigs in PERV insertions and suggests that selection could generate PERV-free lines of pigs more suitable for xenotransplantation.

Crosstalk between the phosphatidylinositol 3-kinase (PI3K) and the transforming growth factor-β signalling pathways play an important role in regulating many cellular functions. However, the molecular mechanisms underpinning this crosstalk remain unclear. Here, we report that PI3K signalling antagonizes the Activin-induced definitive endoderm (DE) differentiation of human embryonic stem cells by attenuating the duration of Smad2/3 activation via the mechanistic target of rapamycin complex 2 (mTORC2). Activation of mTORC2 regulates the phosphorylation of the Smad2/3-T220/T179 linker residue independent of Akt, CDK and Erk activity. This phosphorylation primes receptor-activated Smad2/3 for recruitment of the E3 ubiquitin ligase Nedd4L, which in turn leads to their degradation. Inhibition of PI3K/mTORC2 reduces this phosphorylation and increases the duration of Smad2/3 activity, promoting a more robust mesendoderm and endoderm differentiation. These findings present a new and direct crosstalk mechanism between these two pathways in which mTORC2 functions as a novel and critical mediator., Although crosstalk between the phosphatidylinositol 3-kinase (PI3K) and transforming growth factor-β pathways is important, the mechanism is obscure. Here, Yu et al. show that activation of mTORC2 downstream of PI3K leads to the linker phosphorylation of Smad2/3 and their ubiquitin-dependent degradation.

Summary Habitat segregation has been recognized as an important means of resource partitioning in river fish assemblages. Association between river fishes and habitat features were identified through principal component analysis (PCA). Fish and habitat data were collected in the Kaoping, Tsengwen, Choshui, and Tatu rivers from July 1997 to June 1999 in western Taiwan. Electrofishing was used to collect fishes in grids, and environment variables in the sampled areas were measured immediately after sampling. The first four PCs of depth, velocity, cover, substrate and water temperature variables explained 92.3% of the total variance in habitat characteristics. Varicorhinus barbatulus, Acrossocheilus formosanus and Tilapia mossambica in the upper right quadrant, indicated preference for deep-water habitat. Species usually associated with shallow water habitat include several minnow species. Rhinogobius brunneus, Hemimyzon formosanum, Sinogastromyzon puliensis and Crossostoma lacustre distribution is centred in the upper and lower left, indicating preference for shallow water. Principal component (PC) scores on Zacco pachycephalus, Abbottina brevirostris and Hemiculter leucisculus appeared to have no special preference. Differences in habitat use exhibited by these species may be related to success in finding food and avoiding predators.

The present study was aimed to investigate proteome affected by Panax ginseng extracts in chicken muscles. The whole muscle proteins from chicken fed boiled extracts of 0% (control), 1%, 3%, and 5% Panax ginseng in water were separated by two-dimensional electrophoresis (2-DE) gels using immobilized non-linear gradient (pH 3-10) strips. More than 300 protein spots were detected on silver staining gels. Among them, four protein spots were distinctively up-regulated by Panax ginseng treatments and further investigated by matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS). The obtained MS data were searched against SwissProt database using the Mascot search engine. The up-regulated proteins were finally identified as α- tropomyosin (2 spots), triosephosphate isomerase, and one unknown protein. Based on the known functions of the identified proteins, they are highly related to muscle development and enhanced immunity in chickens. These proteins can give valuable information of biochemical roles for Panax ginseng in chicken meats. (Asian-Aust. J. Anim. Sci. 2005. Vol 18, No. 7 : 922-926)

Paracellular transport of solutes and water accompanies transcellular transport across epithelial barriers and together they serve to maintain internal body composition. However, whether paracellular transport is necessary and why it evolved is unknown. In this commentary I discuss our recent studies to address this question in the proximal tubule of the kidney. Paracellular reabsorption of sodium occurs in the proximal tubule and is mediated by claudin-2. However, deletion of claudin-2 in mice does not affect whole kidney sodium excretion because it can be completely compensated by downtream transcellular transport mechanisms. This occurs at the expense of increased oxygen consumption, tissue hypoxia and increased susceptibility to ischemic injury. It is concluded that paracellular transport acts as an energy saving mechanism to increase transport without consuming additional oxygen. It is speculated that this might be why paracellular transport evolved in leaky epithelia with high transport needs.

The relationship of inflammation and the expression of full-length receptor for advanced glycation end products (flRAGE) on monocytes, plasma levels of RAGE ligand high mobility group box protein 1 (HMGB1), soluble RAGE (sRAGE) and endogenous secretory RAGE (esRAGE) was assessed to elucidate the effect of HMGB1/DNA/RAGE-mediated innate inflammatory responses in patients with lupus nephritis. Cell surface expression of flRAGE was elevated on the monocytes of lupus patients, correlated with plasma HMGB1 levels. Plasma sRAGE level negatively correlated with systemic lupus erythematosus (SLE) disease activity index. Plasma esRAGE level was significantly lower in SLE patients with flare while esRAGE/sRAGE ratio negatively correlated with complement C3 level. HMGB1 alone could moderately induce ex vivo IL-6 production from monocytes, resulting in activation of intracellular p38 mitogen-activated protein kinase (MAPK), c-Jun N-terminal kinase and nuclear factor (NF)-κB. Moreover, toll-like receptor-9 ligand together with HMGB1 exhibited a synergistic effect on IL-6 and IL-12p70 secretions and the phosphorylation of p38 MAPK and NF-κB. Therefore, over-expression of flRAGE in lupus may lead to the amplification of RAGE ligands-mediated inflammatory responses through the activation of p38 MAPK and NF-κB. Plasma sRAGE may serve as a potential biomarker for disease activity and a future therapeutic target in SLE.

Campylobacter jejuni is now recognized as a leading foodborne pathogen, for which poultry products constitute the main transmission route. Two alternative immunomagnetic beads (IMB) were tested for direct detection of C. jejuni ATCC 35918 in artificially inoculated ground poultry meats and culture suspension. Polyclonal anti-Campylobacter antibodies were used to coat tosylactivated Dynabeads. The same antibodies conjugated with biotin were used to label streptavidin-coated beads. After these beads were incubated with inoculated poultry slurry or culture suspension, Campylobacter-bead complexes were separated from other components with a magnet. The capture efficiency was tested by plating bead-captured cells and unbound cells in the supernatant onto Karmali agar. The effects of different coating procedures, incubation time (60, 90, 120 min), numbers of immunomagnetic beads (10(6) to 10(7)/ml) and innoculum levels (10(3) to 10(7) CFU/g or ml) were determined. Without pre-enrichment, this approach could detect 10(4) CFU/g of ground poultry meats. These methods represent a new approach to extracting, concentrating and isolating Campylobacter spp. directly from foods.

A time-resolved fluorescence technique was developed to detect Escherichia coli O157:H7 in ground beef burger. After a 4.5 h enrichment period, streptavidin coated magnetic beads conjugated with biotin-labeled anti E. coli O157:H7 were used to capture the bacteria. The bacteria were, at the same time, also labeled by a nonfluorescent, europium (Eu)-tagged anti-E. coli O157:H7 antibody. The sandwiched bacterial complexes were then concentrated using a magnetic particle concentrator and washed to remove other solution components. Upon addition of an enhancement buffer, the Eu-labels were then released from the antibodies and chelated to nitrilo-triacetic acid (NTA) and trioctylphosphine oxide (TOPO) to form highly fluorescent Eu-(2-NTA)3(TOPO)2–3 micellar complexes. Delayed fluorescence associated with these complexes was measured and its intensity was used to estimate the original bacterial concentration spiked in hamburger. This approach was applied to detect E. coli O157:H7 spiked in hamburgers. The results indicated this method is able to detect 1 CFU/g of the bacteria after a brief enrichment for four and half hours at 37C. Specificity studies indicated that the approach exhibited no or limited cross reactivity to Salmonella typhimurium, E. coli K-12 or Shigella dysenteriae spiked in hamburgers. Thus, the developed approach may be used as a rapid screening procedure for E. coli O157 bacteria in foods.

A modified procedure for magnetic capture of antibody-conjugated bacteria for light addressable potentiometric sensor (LAPS) detection using the Threshold System was developed. Streptavidin coated magnetic beads, partially labeled with biotinylated anti Escherichia coli O157 antibodies, were used to capture Escherichia coli O157:H7. Captured bacteria were further labeled with fluorescein-conjugated anti -E. coli O157:H7 antibodies and urease-labeled. anti-fluorescein antibody. Magnetically concentrated bacteria-containing complexes were then immobilized through streptavidin-biotin interactions on 0.45 μ biotinylated nitro-cellulose membranes assembled as sample sticks for the Threshold instrument. The rate of pH change associated with the production of NH3 by the urease in urea-containing solution was measured by a LAPS incorporated in the Threshold instrument. This approach allowed us to detect 103 to 104 CPU of cultured E. coli O157:H7 in PBS solutions. Furthermore, detectable LAPS signals of the sample sticks remained relatively constant for at least 24 h at 4C. The developed approach was applied to detect the E. coli in beef hamburger spiked with the bacteria. After a 5 to 6-h enrichment at 37C, as low as 1 CFU/g of E. coli O157:H7 in beef hamburger could be detected.

A total of 42 storm-water overland-flow samples were collected from four sampling sites (a highway off-ramp, a gas station, and a low- and high-traffic-volume parking lot). For each sample, the suspended-sediment and water phases were separated and analyzed for 16 polycyclic aromatic hydrocarbons (PAHs). The gas station site produced the highest total PAH loading (2.24 g/yr/m2), followed by the high-traffic-volume parking lot (5.56 X 10-2 g/yr/m2), the highway off-ramp (5.20 × 10-2 g/yr/m2), and the low-traffic-volume parking lot (3.23 × 10-2 g/yr/m2). In several samples, one or more PAHs were detected in the aqueous phase at concentrations above its aqueous solubility. This result suggests the presence of colloidal-size particles capable of sorbing PAHs to an appreciable extent, or the presence of an oil-and-grease microemulsion. Based on rainfall and PAH data from seven discrete storm events, PAH concentrations were usually highest during the “first flush” of storm-water runoff and tapered off rapidly as time progressed. It is apparent from these analyses that storm-water runoff from parking lots, highways, and gas stations is a significant source of PAHs to the environment. Because some of the PAHs are carcinogens or suspected carcinogens, best management practices such as oil/grit separators should be implemented at “hot spots” in urban areas to mitigate potential PAH pollution.

An approach to rapidly detect the presence of viable Escherichia coli O157:H7 is described. Specific immunomagnetic beads were applied to capture the bacteria in different solutions. The captured bacteria were then lysed by commercially available reagents to release cellular ATP which was detected by firefly luciferin-luciferase induced chemiluminescence. The bioenergetic status of the bacteria was adjusted by the addition of glucose, a carbon nutrient source, and carbonyl cyanide meta-chlorophenyl hydrazone (CCCP), a membrane protonophore. The addition of glucose restored oxygen consumption and medium acidification activities and increased the ATP content of harvested bacteria after storage. On the other hand, CCCP enhanced the oxygen consumption and medium acidification but significantly decreased the ATP content. None of the glucose and CCCP effects could be detected with heat-killed and γ-ray irradiated E. coli O157:H7. Thus, immunomagnetic capture of the E. coli followed by testing the bioenergetic responses of captured bacteria would qualitatively determine the presence of viable E. coli O157:H7. When applied, the developed procedure could easily detect the presence of less than one CFU of the E. coli per gram of beef hamburg after a 6-h enrichment at 37C.

A methodology for simulating 2D sheet flow is examined. Although used in the past, a mathematical derivation of the methodology was not presented, and methodology performance without uncertainties introduced by infiltration estimates was not examined. The methodology solves a 1D kinematic wave equation for variable width, curvilinear flow paths. This equation is derived from the 2D kinematic wave equation expressed in orthogonal-curvinlinear coordinates by aligning the coordinate system with runoff surface topography. The 1D equation is solved by a four-point, implicit finite-difference scheme. A sheet flow model using multiple flow paths is described and tested on an impervious surface. Although simulated discharges agree well with observed values, additional testing is needed to further validate model accuracy. Practical considerations for model use are discussed.

The wetland mitigation and storm water management provisions in the 1987 Clean Water Act significantly affect transportation agencies. A common requirement of these federal storm water management provisions and state storm water regulations is the use of best-management practices (BMPs). The Virginia Department of Transportation has constructed more than 200 wetlands and many storm water BMPs, such as detention basins. A potentially cost-effective approach to satisfying wetland mitigation requirements and storm water regulations is to use mitigated wetlands as storm water BMPs. A multifunctional evaluation of two mitigated wetlands receiving highway runoff is presented to examine the feasibility of using mitigated wetlands as storm water BMPs. Influent and effluent water quality and quantity were monitored at the sites during storm events. Vegetation density and diversity and wetland wildlife were examined as functional indicators because they were believed to be the most likely to be impaired by highway runoff. Data collected were stored in a geographic information system, which was developed to serve as a database for current and future monitoring of mitigated wetland sites. Both sites had peak reductions in excess of 40 percent, with attenuation of greater than 90 percent for a system combining a detention basin and a mitigated wetland in series. Removal rates were as high as 90 percent for total suspended solids, 65 percent for chemical oxygen demand, 70 percent for total phosphorus and orthophosphate, and 50 percent for zinc. Despite having highway runoff as a primary water source, both sites support apparently healthy and diverse vegetative communities and provide habitat for a variety of wildlife.

Telomere repeat binding factor 2 (TRF2) is a component of the shelterin complex that is known to bind and protect telomeric DNA, yet the detection of TRF2 in extra-telomeric regions of chromosomes suggests other roles for TRF2 besides telomere protection. Here, we demonstrate that TRF2 plays a critical role in antagonizing the repressive function of neuron-restrictive silencer factor, also known as repressor element-1 silencing transcription factor (REST), during the neural differentiation of human embryonic stem cells (hESCs) by enhancing the expression of a truncated REST splice isoform we term human REST4 (hREST4) due to its similarity to rodent REST4. We show that TRF2 is specifically upregulated during hESC neural differentiation concordantly with an increase in the expression of hREST4 and that both proteins are highly expressed in NPCs. Overexpression of TRF2 in hESCs increases hREST4 levels and induces their neural differentiation, whereas TRF2 knockdown in hESCs and NPCs reduces hREST4 expression, hindering their ability to differentiate to the neural lineage. Concurrently, we show that TRF2 directly interacts with the C-terminal of hREST4 through its TRF2 core binding motif [F/Y]xL, protecting hREST4 from ubiquitin-mediated proteasomal degradation and consequently furthering neural induction. Thus, the TRF2-mediated counterbalance between hREST4 and REST is vital for both the generation and maintenance of NPCs, suggesting an important role for TRF2 in both neurogenesis and function of the central nervous system. Stem Cells 2014;32:2111–2122

Claudins are the main determinants of barrier properties of the tight junction. Many claudins have been shown to act by tightening the paracellular pathway, but several function as paracellular channels. While some depend on the endogenous claudin background of the analyzed cell line, for other claudins, a distinct charge-selectivity has been shown. This paper portrays cation-selective (claudin-2, claudin-10b, claudin-15) and anion-selective (claudin-10a, claudin-17) claudins and claudins with debatable channel properties (claudin-4, claudin-7, claudin-16). It also describes molecular properties determining the observed charge-selectivity and pore properties in general. In leaky tissues, they widely determine overall transport characteristics by providing paracellular ion-selective pathways. In small intestine, claudin-2 and claudin-15 replace each other in the developing gut. In kidney proximal tubules, claudin-2, claudin-10, and claudin-17 allow for paracellular reabsorption of sodium, chloride, and water.

One of the challenges in studying early differentiation of human embryonic stem cells (hESCs) is being able to discriminate the initial differentiated cells from the original pluripotent stem cells and their committed progenies. It remains unclear how a pluripotent stem cell becomes a lineage-specific cell type during early development, and how, or if, pluripotent genes, such as Oct4 and Sox2, play a role in this transition. Here, by studying the dynamic changes in the expression of embryonic surface antigens, we identified the sequential loss of Tra-1-81 and SSEA4 during hESC neural differentiation and isolated a transient Tra-1-81(-)/SSEA4(+) (TR-/S4+) cell population in the early stage of neural differentiation. These cells are distinct from both undifferentiated hESCs and their committed neural progenitor cells (NPCs) in their gene expression profiles and response to extracellular signalling; they co-express both the pluripotent gene Oct4 and the neural marker Pax6. Furthermore, these TR-/S4+ cells are able to produce cells of both neural and non-neural lineages, depending on their environmental cues. Our results demonstrate that expression of the pluripotent factor Oct4 is progressively downregulated and is accompanied by the gradual upregulation of neural genes, whereas the pluripotent factor Sox2 is consistently expressed at high levels, indicating that these pluripotent factors may play different roles in the regulation of neural differentiation. The identification of TR-S4+ cells provides a cell model for further elucidation of the molecular mechanisms underlying hESC neural differentiation.

Adoptive immunotherapies composed of T cells engineered to express a chimeric antigen receptor (CAR) offer an attractive strategy for treatment of human cancer. However, CARs have a fixed antigen specificity such that only one tumor-associated antigen (TAA) can be targeted, limiting the efficacy that can be achieved because of heterogeneous TAA expression. For this reason, a more generalized and effective application of CAR therapy would benefit from the capability to produce large panels of CARs against many known TAAs. In this study, we show a novel strategy to extend the recognition specificity potential of a bioengineered lymphocyte population, allowing flexible approaches to redirect T cells against various TAAs. Our strategy employs a biotin-binding immune receptor (BBIR) composed of an extracellular-modified avidin linked to an intracellular T-cell signaling domain. BBIR T cells recognized and bound exclusively to cancer cells pretargeted with specific biotinylated molecules. The versatility afforded by BBIRs permitted sequential or simultaneous targeting of a combination of distinct antigens. Together, our findings show that a platform of universal T-cell specificity can significantly extend conventional CAR approaches, permitting the tailored generation of T cells of unlimited antigen specificity for improving the effectiveness of adoptive T-cell immunotherapies for cancer. Cancer Res; 72(7); 1844–52. ©2012 AACR.

Polyvinylidene fluoride (PVDF) flat ultrafiltration membranes modified by nano-sized alumina (Al₂O₃) particles were prepared by phase inversion process and their properties and anti-fouling performances were examined. The influence of three types of natural organic matters on the modified membrane fouling was also studied. Raw water was taken from two different locations, i.e., Harbin and Zhaoyuan, of Songhua River. Dissolved organic compounds in the raw water were fractionated using XAD resins into three fractions, i.e., hydrophobic fraction, transphilic fraction, and hydrophilic fraction (HPI). The three adsorbed compounds were further eluted and dissolved into distilled water respectively to prepare the feed for the fouling tests. All solutions were adjusted to a concentration of 10.6 mg C/L, which equals to the total organic carbon (TOC) of the raw water. Results show that the addition of nano-Al₂O₃ particulars did not affect the inherent traits of the PVDF membranes, however, its surface hydrophilic properties were improved significantly with the addition of nanoparticles and anti-fouling performance was enhanced as well. The HPIs in the Songhua River were the main foulant, causing more fouling to membrane than hydrophobic and transphilic matters.

Claudins are tight junction membrane proteins that act as paracellular pores and barriers and regulate epithelial permeability to small ions. A key step in understanding the function of any claudin isoform is the in vitro measurement of its ion permeability and selectivity. Herein, we describe methods to generate clonal lines with stable inducible overexpression of claudins in Madin-Darby canine kidney epithelial cells, measure conductance and diffusion potentials in Ussing chambers, correct for liquid junction potentials, and derive quantitatively accurate values for individual ion permeabilities.

We aimed to identify the variables associated with ovarian hyperstimulation in Asian patients and compare them with western standards.This is a retrospective case record analysis of 79 patients with ovarian hyperstimulation at a tertiary restructured hospital.Gonadotropin doses resulting in hyperstimulation did not vary between long and antagonist cycles in women less than 35 years with polycystic ovaries (PCO). Mean oestradiol levels at hyperstimulation were not different between PCO and non-PCO patients in a long cycle. Hyperstimulation was mostly due to higher starting doses. Total follicle counts of more than 20 on Day 5-7 after stimulation may be predictive of subsequent hyperstimulation. Hyperstimulation tended to be more severe in lean PCO patients, and prophylactic albumin helped to reduce its severity.Gonadotropin doses at stimulation should start at 150 iu or less in women below 35 years of age, with a step up of 37.5 iu, as necessary. Transfer should be abandoned in the presence of high oestradiol levels (more than 5,000 pg/ml), when the total number of intermediate and large follicle count exceeds 30 on the day of oocyte retrieval, or when more than 19 eggs are retrieved. Variables in the Asian population appear to be similar to those in the western population.

This paper presents an integrated methodology that allows determining the probability of noncompliance for a given wastewater treatment plant. The methodology applies fault-tree analysis, which uses failure probabilities of individual components, to predict the overall system failure probability. The methodology can be divided into two parts : risk identification and risk quantification. In risk identification, the key components in the system are determined by analyzing the contribution of individual component failures toward system failure (i.e., noncompliance). In risk quantification, a fault-tree model is constructed for the particular system, component failure probabilities are estimated, and the fault-tree model is evaluated to determine the probability of occurrence of the top event (i.e., noncompliance). A list can be developed that ranks critical events on the basis of their contributions to the probability of noncompliance. Such a ranking should assist managers to determine which components require most attention for a better performance of the entire system. A wastewater treatment plant for treating metal-bearing rinse water from an electroplating industry is used as an example to demonstrate the application of this methodology.

The ability of the motility enrichment Fung-Yu tube procedure with Oxyrase™ enzyme to detect the presence of Listeria monocytogenes inoculated into ground beef samples was compared to the USDA-FSIS method. Three strains of L. monocytogenes (LM 101M, LM 103M, and Scott A) were inoculated separately into sterilized ground beef or culture broth. The inoculum levels used were as low as 1 to 1000 Listeria cells per g of meat or per ml of broth. The Fung-Yu tube procedure produced results as sensitive as the USDA procedures and provided a shorter detection time of 26-48 h. A total of 215 retail-level meat and poultry products were analyzed comparatively by the Fung-Yu tube and the GENETRAK® DNA hybridization methods for Listeria detection. Six Listeria spp. ( L. denitrificans , L. grayi , L. innocua , L. ivanovii , L. monocytogenes , and L. murrayi ) were identified among the isolates. All 48 presumptively positive samples determined by the Fung-Yu tube method were further confirmed to harbor Listeria by biochemical tests. Eleven samples were missed by the GENETRAK® procedure, probably because of the enrichment procedure. L. monocytogenes was isolated from ground beef, pork sausage, smokie links, and cheese hot dogs. Among cooked samples examined, only cheese hot dogs and macaroni and cheese loaf showed substantial incidence of Listeria contamination.

Cucumber mosaic virus (CMV) isolates are currently divided into two main groups, I and II according to their genomic sequences. The group I is further divided into two Subgroups IA and IB. We performed a phylogenetic analysis of the genomic regions containing 1a, 2a, 2b, coal protein (CP), and movement protein (MP) genes of 5 CMV isolates from China and other 28 CMV isolates available in the GenBank. The results indicated that CMV isolates could be genetically divided into three groups I, II, and III according to the genes encoding MP, CP, 1a, and 2a proteins and to the 2 groups according to the gene 2b. Group I Could be further divided into two Subgroups (IA and IB) according to the genes encoding CP, MP, 2a, and 2b proteins and to the three subgroups (IA, IB, and IC) according to the gene encoding Ia protein. Four of 5 examined Chinese CMV isolates belonged to the subgroup IB, while the remaining isolate was it natural inter-subgroup reassortant. We found that the 2b gene of CMV was under positive selection, while the other genes Were under negative selection. No evidence of the selection associated with a host adaptation Or geographic distribution Was found.

This paper presents rapid fabrication process and characterization of porous nylon with electro-active dopants for the applications of flexible tactile sensor array, moisture sensor, and actuator. Porous nylon was used as the matrix integrated on a flexible copper-PI film, which provided flexible mechanical properties. Inside the matrix, polypyrrole was electrochemically deposited on the pre-defined interdigitated copper electrodes and acted as conductive dopant. The electro-mechanical characteristics of the fabricated sensors for different applications were measured. The deformation of the electro-active actuator was simulated.

The use of an oxygen-reducing membrane fraction to stimulate growth of some anaerobic bacteria has been reported. In this study, stimulated recovery of Escherichia coli 0157:H7, Salmonella typhimurium, Streptococcus faecalis, and heat-injured Listeria monocytogenes was achieved by using broth media supplemented with OxyraseTM (membrane-bound enzyme system derived from E. coli). The OxyraseTMenzyme allowed rapid growth of these facultatively anaerobic organisms in a nonselective broth. The activity of OxyraseTMin four different selective enrichment broths to support growth of L. monocytogenes also was evaluated. Among tested broths, FDA-approved Listeria Enrichment Broth containing OxyraseTMwas found to be substantially superior for facilitating the growth of L. monocytogenes. OxyraseTMpromoted a significantly greater number of L. monocytogenes than commonly used but nonspecific reducing agents, such as L-cysteine HCl and sodium thioglycolate. These findings indicated that all organisms tested can be grown well in liquid media using the oxygen-consuming membrane fragments to achieve and maintain oxygen-limited conditions. The OxyraseTMenzyme system has potential applications in some selective media and other diagnostic tests specified for rapid detection of these facultatively anaerobic pathogens.

A rapid and simple method using a U-shaped glass apparatus (Fung-Yu tube) for early determination of the presence of Listeria monocytogenes and Listeria species in mixed cultures and inoculated meat samples has been developed. This system utilizes unique biochemical and physical properties of Listeria for selective enrichment. Fraser broth was used as a selective enrichment broth especially for observation of esculin hydrolysis (blackening of broth), and semisolid Modified Oxford agar was used for selective detection of motility of Listeria. When Fung-Yu tubes containing 0.1 unit/mL of OxyraseTM (membrane fractions of Escherichia coli) were inoculated with L. monocytogenes, an enhanced early growth of L. monocytogenes occurred. A presumptive positive result for low numbers of L. monocytogenes (1–100 CFU/g) in the presence of large numbers of competitive microflora in pre-enriched (24 h) ground beef samples using the Fung-Yu tube method with the aid of OxyraseTMwas obtainable within 10 h. Using this system, isolation of Listeria in the presence of mixed bacterial flora (44 species), such as Bacillus, Escherichia, Klebsiella, Proteus, Salmonella, Shigella, Staphylococcus, and Streptococcus, and in inoculated ground beef was successful in 24–48 h. The Fung-Yu tube procedure is a highly sensitive, selective, and easy-to-use method to separate and isolate L. monocytogenes and other Listeria spp. from other contaminating microorganisms in meats.

This study aims to evaluate the differences in oocyte stimulation, endometrial thickness, fertilisation rate and embryo quality at in-vitro fertilisation (IVF) in patients with documented growth hormone (GH) deficiency, after GH supplementation.This was a retrospective analysis of 20 cases of patients who were pregnant and had GH supplementation during IVF at the Singapore General Hospital between 1993 and 2003. All these patients had previously failed IVF due to poor stimulation, poor egg quality, poor fertilisation at intracytoplasmic sperm injection (ICSI) or failed implantation, and they had documented GH deficiency. These initial cycles were compared with their subsequent IVF cycles with GH supplementation. A non-parametric test was used for statistical analysis.Embryo quality, determined by scoring the embryos on Day two using morphology, improved significantly after supplementation of GH (p-value is less than 0.001, median embryo score increased from 10.7 to 16). There was also a statistically significant increase in the fertilisation rate for those patients who had ICSI. There was no statistical difference in the number of oocytes retrieved or in the mean endometrial thickness with GH.This study implies that GH supplementation may improve embryo quality in selected patients with GH deficiency. Its role in improving fertilisation rate at ICSI merits further research and evaluation.

Pregnancy is a normal physiological state that is characterised by significant adaptive changes, many of which take place in the cardiovascular system. These adaptations are believed to be the cause for the increased incidence in cardiac arrhythmias in pregnancy and particularly, in labour. We report an unusual case of a healthy 32-year-old primigravida who developed profound intrapartum bradycardia which persisted throughout labour. Spontaneous recovery to pre-labour baseline heart rate occurred following spontaneous vaginal delivery. Maternal and foetal statuses remained satisfactory during labour. This case report underscores the importance of recognising that arrhythmias in various forms are common in labour. In the absence of detectable underlying cardiac disease or maternal and foetal compromise, continuation of the labour with a view to vaginal delivery should be the goal.

Lactoferrin, which exhibits antibacterial activity to protect infants from infectious disease, is a major component of colostrum and milk. Lactoferrin was purified from the colostrum of Korean Native goat, and the cDNA from the mammary gland mRNA of the animal was cloned and sequenced. The nucleotide sequence of the lactoferrin gene of Korean Native goat was found to differ in 15 sites from that of the goat lactoferrin gene reported earlier. This difference in nucleotide sequence resulted in six amino acid substitutions: five in the N-lobe and one in the C-lobe. The antibacterial activity of Korean Native goat lactoferrin was found to be greater than that of Sannen goat lactoferrin.

Renal net acid excretion requires tubular reabsorption of filtered bicarbonate, followed by secretion of protons and ammonium in the collecting duct, generating steep transtubular gradients for these ions. To prevent passive backleak of these ions, the tight junctions in the collecting duct must be highly impermeable to these ions. We previously generated a Madin-Darby canine kidney (MDCK II) cell line with inducible expression of claudin-8, a tight junction protein expressed in the collecting duct. In these cells, claudin-8 was shown to function as a paracellular barrier to alkali metal and divalent cations. We have now used this model to test the hypothesis that claudin-8 also functions as a paracellular barrier to acidic or basic ions involved in renal acid excretion. We developed a series of precise and unbiased methods, based on a combination of diffusion potential, short-circuit current, and pH stat measurements, to estimate paracellular permeability to protons, ammonium and bicarbonate in MDCK II cells. We found that under control conditions (i.e. in the absence of claudin-8), these cells are highly permeable to the acidic and basic ions tested. Interestingly, proton permeation exhibited an unusually low activation energy similar to that in bulk solution. This suggests that paracellular proton transfer may occur by a Grotthuss mechanism, implying that the paracellular pores are sufficiently wide to accommodate water molecules in a freely mobile state. Induction of claudin-8 expression reduces permeability not only to protons, but also to ammonium and bicarbonate. We conclude that claudin-8 probably functions to limit the passive leak of these three ions via paracellular routes, thereby playing a permissive role in urinary net acid excretion.

Transcatheter uterine artery embolisation (UAE) for the treatment of symptomatic uterine enlargement due to fibroids has been performed in several overseas centres with promising results. We report our experience with UAE in Singapore General Hospital.Twenty women with symptomatic uterine fibroids who declined surgery were treated by transcatheter UAE. The uterine arteries were selectively catheterised and embolised with polyvinyl alcohol particles. Post-procedure analgesia was administered via a patient-controlled analgesia pump. The patients were followed up at regular intervals clinically and with transabdominal ultrasonography.Transcatheter UAE was performed on all patients with no major complications. Nineteen patients had both uterine arteries embolised while 1 patient had only the right uterine artery embolised on account of hypoplasia of the left uterine artery. The mean hospital stay was 3.5 days (range, 2 to 9). At a mean follow-up of 56 weeks (range, 6 to 168), all patients reported improvements in their presenting symptoms. Objective improvement in terms of reduction of uterine and fibroid sizes was determined on ultrasonography. The median size of the uterine volume decreased from 308 to 187 mL while the median diameter of the largest fibroid reduced from 6.2 to 4.6 cm. The median haemoglobin level increased to 12.7 g/dL from the pre-procedural median of 9.9 g/dL. One patient, who initially responded with a decrease in uterine and dominant fibroid size, became symptomatic (menorrhagia) at 6 months post-embolisation. She underwent a repeat procedure with complete resolution of symptoms. A second patient had recurrence of symptoms at 12 months, but was subsequently lost to follow-up.Mid-term results of UAE for the treatment of symptomatic fibroids in our hospital indicate this to be a safe and effective therapeutic option.

Fasting during the month of Ramadan is compulsory in the Muslim faith. Although pregnant women may be exempted, many still choose to fast while others are more careful in practising it. This survey examines the practice of fasting among pregnant Muslim women in Singapore based on the prevalence in relation to factors such as parity, social and economic circumstances. It also analyses the factors that influence the decision to fast and the successful completion of the fast, and examines their knowledge, belief and attitudes on fasting during the holy month of Ramadan.This is a retrospective study of all Muslim women who were pregnant and received antenatal care in our hospital during the month of Ramadan from 17 November 2001 to 16 December 2001. A four-page questionnaire was mailed to all eligible subjects in March 2002.Of 202 eligible subjects, 125 responded via mail and 57 via the phone, yielding a response rate of 90 percent. Most women chose to fast during pregnancy, and they do so with adequate support from their spouses and family members. Most of them do not experience any adversities during fasting and even if they do, most were able to overcome them. Most women adopt a positive attitude towards fasting. However, there is a lack of basic religious knowledge among many pregnant women pertaining to the Muslim law of fasting during pregnancy.Doctors and health workers need to understand the religious obligations of a Muslim towards fasting during Ramadan. Only through this can a doctor adequately counsel Muslim patients and allow informed decision with regards to fasting. With respect to pregnant women, provisions are allowed for them not to observe fasting.

The mature spermatozoa of two Taiwan protandrous hermaphrodite Sparidae Acanthopagrus berda and Acanthopagrus australis are investigated and compared with those of other two Sparidae (Lagodon rhomboids and Archosargus probatocephus) from the Western hemisphere. Ultrastructurally the spermatozoon of these four species has a spherical, homogeneously electron-dense nucleus with an axial nuclear fossa. The midpiece contains one to four spherical mitochondria and encircles the basal body of the flagellum. The mature spermatozoa of the four species are of the primitive or ect-aquasperm form and conform to the teleostean type I spermatozoon with the flagellar axis inserts perpendicular and medial to the nuclear fossa. Variation in the depths of the nuclear fossa and mitochondria number is substantial in these four Sparidae species. This study provide useful systematic characters to the existing knowledge of comparative spermatology of Sparidae.

This study was to develop computer aided design system of anterior prosthesis, which can improve information communication among doctors, technicians, patients and raise anterior prosthesis cosmetic effect.Digital camera was used for image capture; Space field method, neighboring field average method, midst value filter method, and image average method were used for image pre-process; sample teeth were constructed; anterior prosthesis were automatically designed through tooth feature extraction.86 patients were prosthetically designed through this CAD system with excellent results.This system implemented anterior prosthesis CAD rapidly, guided clinical application and promoted information process in the field of prosthetics.

Investigations play a pivotal role in the workup for infertility. The results must be interpreted carefully as these assess dynamic function. Evidence-based guidelines are useful in the selection of appropriate tests.A review of current evidence-based guidelines for the investigation and management of the infertile couple is undertaken.The main areas that correlate with fecundability are ovulatory function, tubal patency and semen analysis.The appropriate selection of investigations based on problem areas identified by history and physical examination would guide the physician in the management of the infertile couple.

Vesico-uterine fistula is a very rare complication of lower caesarean section. There has only been two cases seen at the Department of Urology in the past 2 decades. Patients usually present in the early post operative period with the problem of continuous urinary incontinence. On the rare occasion, recurrent urinary tract infection, recurrent gross painless haematuria, or secondary infertility associated with secondary amenorrhoea would be the presenting complaint.

Two microbiological sampling techniques, excision and sponge swabbing, were compared by determining counts of aerobic bacteria, coliforms and injured coliforms from 20 de-haired swine carcasses before and after chilling. Excised jowl skin produced significantly greater counts of the three types of bacteria than sponge swabs. Aerobic bacteria, coliforms and injured coliforms recovered by sponge swabbing carcasses before chilling were 11.6%, 0.9% and 11.0% of excised samples, respectively; the corresponding percentages recovered after chilling were 23.9%, 11.1% and 5.0%. Numbers of all bacteria present on the post-chill carcasses were substantially lower than on the pre-chill carcasses. Excision usually produced more countable plates for coliforms and injured coliforms on chilled carcasses than sponge swabbing and therefore, is more suitable in estimating low numbers of faecal bacteria on chilled carcasses. To explore the possible structural bases for these findings, skin samples were inoculated with 10(2)-10(7) cfu cm(-2) faecal bacteria and examined by scanning electron microscopy. Chilled samples showed bacteria and biofilm embedded in superficial crevices, which underlies a possible reason for the lower recovery of bacterial cells by the sponge swabbing. The study indicates that the differences between sampling techniques may be a result of the chilling process of swine carcasses.

An improved process using magnetic capture of antibody-conjugated bacteria for light addressable potentiometric sensor detection by the Threshold instrument was developed. Cells of Escherichia coli 0157:H7 were captured by the biotinylated anti-E. coli 0157 antibodies conjugated to streptavidin coated magnetic beads. Magnetically concentrated bacteria were further labeled with by fluorescein-conjugated anti-E. coli 0157 antibodies that were bound to urease-conjugated anti-fluorescein antibody. The whole bacteria-containing complex was then immobilized on 0.45 μ biotinylated nitro-cellulose membranes via streptavidin-biotin interactions. The rates of pH change associated with the production of NH 3 by conjugated urease were measured by a LAPS technique incorporated in the Threshold instrument. This approach allowed us to detect -10 4 CFU of cultured E. coli 0157:H7 in tris-buffered saline (TBS). The same approach was applied to detect the E. coli in beef hamburger spiked with the bacteria. After a 5 to 6-hour enrichment, as low as 1 CFU/g of E. coli 0157:H7 in the hamburger could be detected. In addition, the immobilized bacterial complexes on the nitro-cellulose membranes exhibited a stability longer than 48 h at 4 and 22 °C in TBS allowing the possibility of conveniently shipping collected samples rather than raw beef to testing laboratories.

Surgical retrieval of spermatozoa for in-vitro fertilisation (IVF) programs for severely oligospermic men has been in use for several years now. In the recent 2 to 3 years, clinicians have begun to move towards non-surgical methods of retrieving sperm in certain selected groups of men. Percutaneous epididymal sperm aspiration (PESA) has had good results in terms of number of sperm obtained, as well as the fertilisation and pregnancy rates. The first reported use of such a technique in Singapore is described.

Background The ‘2 week wait’ directive (Health Service Circular (HSC) 1998/242) guaranteeing that ‘everyone with suspected breast cancer will be able to see a specialist within two weeks of their general practitioner (GP) deciding they need to be seen urgently’ is a unique audited approach to access for the British National Health Service, the effects of which have been assessed in a non-academic symptomatic breast clinic. Methods New GP referrals (n = 607) were reviewed prospectively in two comparable 3-month intervals, beginning 1 April 1998 and 1 April 1999, to determine the probability of a breast cancer diagnosis from the referral letter and the effects of the directive on waiting times for appointments and utilization of clinics. Results The urgency of referral was not specified in 53 per cent of GP referrals. For the ‘urgent’ cases (25 per cent of all new referrals) the probability of a final diagnosis of breast cancer was 0·19. The breast specialists prospectively achieved a rate of 0·26 from 99 per cent of the same referral letters. ‘Urgent’ referrals did not wait significantly longer in 1999 (median 9 versus 10 days) but waiting times for new appointments overall increased (13 versus 16 days; P < 0·01), and this was greatest for ‘routine’ referrals (14 versus 21 days; P < 0·001). These changes were caused by an increase in the number of clinic appointments, due to significant increases in median number of visits to diagnosis or discharge and clinic non-attendance in 1999, resulting in overbooking. Telephonic communications were associated with faster median access times (fax 8 days; telephone 2 days), relative to mailed referrals (19 days) (P < 0·01). Conclusion Breast specialists were better overall at assessing the probability of a breast cancer diagnosis. The waiting time for ‘urgent’ appointments was unchanged following HSC 1998/242, but there was an increased wait for other patients, especially those assessed as having a lower probability of cancer.

Using starch ampicillin agar, qualitative and quantitative determinations of Aeromonas spp. were made at several sites during swine carcass dressing and cutting. Aeromonas spp. were observed at all sites surveyed. Levels increased during shackling and passage through the first and middle polisher/washers, and significantly decreased during the singeing steps. Passage through the final polisher/washer caused a small increase in levels in Aeromonas spp. and these levels then remained constant during the rest of the carcass dressing operation. Aeromonas spp. were also isolated from the room where the carcasses were cut into wholesale cuts and cuts for further processing. Presumptive Aeromonas spp. cultures isolated from the different sites were confirmed as belonging to the genus Aeromonas and then speciated using the biochemical scheme of Joseph and Carnahan; 81% of the cultures were identified at A. hydrophila. Since most isolates were A. hydrophila, determination of the origin of isolates from different sites in the processing plant must await utilizing molecular biotyping techniques on the cultures. These results indicate the Aeromonas spp. occurs extensively in the swine dressing environment and thus represents a possible public health hazard and potential spoilage concern. Changes in cleaning and sanitizing of equipment may be necessary during swine carcass dressing and cutting to guard against this pathogen.