Age-related macular degeneration and protective effect of HMG Co-A reductase inhibitors (statins): results from the National Health and Nutrition Examination Survey 2005-2008

PURPOSE

To determine the association of hydroxymethylglutarylcoenzyme A (HMG Co-A) reductase inhibitor (statin) use with the prevalence of age-related macular degeneration (AMD).

METHODS

This cross-sectional study included 5604 participants in the National Health and Nutrition Examination Survey (NHANES) from 2005 to 2008, ≥ 40 years of age, who were ascertained with regard to the diagnosis of AMD, the use of statins, and comorbidities and health-related behaviors such as smoking.

RESULTS

The mean age of participants denying or confirming a history of AMD was 68 (SEM 0.90) and 55 (SEM 0.36) years, respectively. Individuals 68 years of age or older who were classified as long-term users of statins had statistically significant less self-reported AMD (odds ratio (OR) 0.64, 95% confidence interval (CI) 0.49-0.84; P=0.002), after adjusting for potential confounding variables. No significant association was found between the prevalence of AMD and statin consumption among subjects between 40 and 67 years of age (OR 1.61, 95% CI 0.85-3.03; P=0.137).

CONCLUSIONS

Our results suggest a possible beneficial effect of statin intake for the prevention of AMD in individuals 68 years of age or older.

Atomic structure evolution during solidification of liquid niobium from ab initio molecular dynamics simulations

Atomic structure transitions of liquid niobium during solidification, at different temperatures from 3200 to 1500 K, were studied by using ab initio molecular dynamics simulations. The local atomic structure variations with temperature are investigated by using the pair-correlation function, the structure factor, the bond-angle distribution function, the Honeycutt-Anderson index, Voronoi tessellation and the cluster alignment methods. Our results clearly show that, upon quenching, the icosahedral short-range order dominates in the stable liquid and supercooled liquid states before the system transforms to crystalline body-center cubic phase at a temperature of about 1830 K.

An overview on natural polysaccharides with antioxidant properties

Pharmacotherapy using natural substances can be currently regarded as a very promising future alternative to conventional therapy. With the rapid development of biotechnologies and analytical techniques, a great number of methods have been developed for the identification and quantification of the material, extracts, and products of natural ingredients. The advances available today. The need for safer drugs without side effects has led to the use of natural ingredients with proven safety. In recent years, some bioactive polysaccharides isolated from natural sources have attracted much attention in the field of biochemistry and pharmacology. As an example, polysaccharides or their glycoconjugates were shown to exhibit multiple biological activities including anticarcinogenic, anticoagulant, immunostimulating, antioxidant, etc. During the last several years, we have witnessed a steady expansion in the number of publications that focus in antioxidant polysaccharides. This review presents current findings on the latest advancements and trends in antioxidant polysaccharides isolated from the following: plants, fungi, bacteria, animal sources, and algae. Some interesting studies focus on investigation of the relationship between their structure and antioxidant activity, elucidation of their antioxidant mechanism at the molecular level, and improvement of their various biological activities by chemical modifications. Although the mechanism of their antioxidant action is still not completely clear, these polysaccharides are suggested to enhance cell-mediated immune responses in vivo and in vitro and act as biological response modifiers.

Control of trichloroethylene plume migration using a biobarrier system: a field-scale study

The objective of this field-scale study was to evaluate the effectiveness of controlling trichloroethylene (TCE) plume migration using the polycolloid substrate (PS) biobarrier. The developed PS (containing soybean oil, lactate and surfactants) could release substrate to enhance the TCE dechlorination. In this study, a biobarrier comprising PS injection wells was installed. Injection wells were installed at 5-m intervals, and approximately 15 L of PS was injected into each well. Results show that TCE concentrations in the injection wells dropped from an average of 87 μg/L to below 1 μg/L after 35 days of PS injection. The total organic carbon concentrations in the injection wells increased from an average of 2.1-543 mg/L after 30 days of PS injection. The dissolved oxygen (DO) concentrations and oxidation-reduction potential (ORP) values dropped from an average of 1.6 mg/L to below 0.1 mg/L and from 124 mv to -14 mv after 20 days of injection, respectively. The DO and ORP remained in anaerobic conditions during the remaining 100 days of the operational period. TCE degradation by-products were observed in groundwater samples during the operational period. This reveals that the addition of PS could effectively enhance the reductive dechlorinating of TCE.

Thermal response of a dental tissue induced by femtosecond laser pulses

This paper reports a theoretical and experimental study for thermal transport in a thin slice of human tooth induced by a 120 fs, 800 nm pulse laser at a repetition rate of 1 kHz. The surface reflectivity of enamel and the convection heat transfer coefficient were determined using an inverse heat transfer analysis. Instead of a fully three-dimensional modeling, two simplified two-dimensional (2D) planar and axisymmetric heat conduction models were proposed to simulate the temperature fields. The temperature responses obtained from the 2D planar and axisymmetric model agree well with the experimental measurements. On the other hand, the one-dimensional (1D) result significantly differs from the 2D axisymmetric one, suggesting that care should be taken when a 1D thermal model is considered for estimating temperature response.

Effects of strontium impurity on the structure and dynamics of Al88Si12 liquid

The effects of strontium modification on the structure and dynamics of Al88Si12 liquid are studied by means of ab initio molecular dynamics simulations. By replacing 0.5% and 4.0% of Al with Sr, we show that the addition of Sr lowers the self-diffusion of Al and Si of the liquid and reduces the nearest-neighbor correlation between Si atoms. The simulation provides an explanation for the change in morphology of the eutectic phases observed in rapidly solidified Al-Si alloys modified with Sr.

The effect of soy isoflavone on bone mineral density in postmenopausal Taiwanese women with bone loss: a 2-year randomized double-blind placebo-controlled study

The treatment of 300-mg/day isoflavones (aglycone equivalents) (172.5 mg genistein + 127.5 mg daidzein) for 2 years failed to prevent lumbar spine and total proximal femur bone mineral density (BMD) from declining as compared with the placebo group in a randomized, double-blind, two-arm designed study enrolling 431 postmenopausal women 45-65 years old.

INTRODUCTION

This study evaluated the effects of soy isoflavones on bone metabolism in postmenopausal women.

METHODS

Four hundred and thirty-one women, aged 45-65 years, orally consumed 300-mg/day isoflavones (aglycone equivalents) or a placebo for 2 years in a parallel group, randomized, double-blind, two-arm study. Each participant also ingested 600 mg of calcium and 125 IU of vitamin D(3) per day. The BMD of the lumbar spine and total proximal femur were measured using dual-energy X-ray absorptiometry at baseline and every half-year thereafter. Serum bone-specific alkaline phosphatase, urinary N-telopeptide of type 1 collagen/creatinine, and other safety assessments were examined regularly.

RESULTS

Two hundred out of 217 subjects in the isoflavone group and 199 out of 214 cases in placebo group completed the treatment. Serum concentrations of isoflavone metabolites, genistein and daidzein, of the intervention group were remarkably elevated following intake of isoflavones (p < 0.001). However, differences in the mean percentage changes of BMD throughout the treatment period were not statistically significant (lumbar spine, p = 0.42; total femur, p = 0.39) between the isoflavone and placebo groups, according to the generalized estimating equation (GEE) method. A significant time trend of bone loss was observed at both sites as assessed by the GEE method following repeated measurement of BMD (p < 0.001). Differences in bone marker levels were not significant between the two treatment groups.

CONCLUSION

Treatment with 300-mg/day isoflavones (aglycone equivalents) failed to prevent a decline in BMD in the lumbar spine or total femur compared with the placebo group.

Salmonella rarely detected in Mississippi coastal waters and sediment

AIMS

Standards for the rapid detection of individual pathogens from environmental samples have not been developed, but in their absence, the use of molecular-based detection methods coupled with traditional microbiology techniques allows for rapid and accurate pathogen detection from environmental waters and sediment. The aim of this research was to combine the use of enrichment with PCR for detection of Salmonella in Mississippi coastal waters and sediment and observe if that presence correlated with levels of enterococci and climatological variables.

METHODS AND RESULTS

Salmonella were primarily found in samples that underwent nutrient enrichment and were present more frequently in freshwater than marine waters. Salmonella were detected infrequently in marine and freshwater sediments. There was a significant positive correlation between the presence of detectable Salmonella and the average enterococcal count. An inverse relationship, however, was observed between the frequency of detection and the levels of salinity, turbidity and sunlight exposure.

CONCLUSIONS

Results from this study indicated the presence of Salmonella in Mississippi coastal waters, and sediments are very low with significant differences between freshwater and marine environments.

SIGNIFICANCE AND IMPACT OF THE STUDY

Using pathogenic and novel nonpathogenic molecular markers, Salmonella do not appear to be a significant pathogenic genus along the Mississippi Coast.

Alpinia pricei Hayata rhizome extracts have suppressive and preventive potencies against hypercholesterolemia

The aim of this study was to investigate the effects of 70% ethanol extracts of Alpinia pricei (APE) on lipid profiles and lipid peroxidation. Syrian hamsters were fed a chow-based hypercholesterolemic diet (HCD) for 2 weeks to induce hypercholesterolemia (>250 mg/dl). To evaluate the potency of APE in suppressing hypercholesterolemia, hamsters were then fed HCD plus a high dose (500 mg/kg body weight) or a low dose (250 mg/kg body weight) of APE, or only HCD for another 4 weeks. We found that hypercholesterolemic hamsters fed a high dose of APE had lower serum total cholesterol (TC) and low-density lipoprotein-cholesterol (LDL-C) levels, lower thiobarbituric acid reactive substances (TBARS) and alanine aminotransferase (ALT) activities, lower atherogenic indices (LDL-C/HDL-C and TC/HDL-C ratios), and lower hepatic protein expression of peroxisome proliferators activated receptor gamma (PPARgamma) than hamsters fed a HCD diet. In addition, we also determined the preventive effects of APE on hamsters fed a HCD for 6 weeks. The hypocholesterolemic effects were also found in hamsters co-fed a high dose of APE and HCD for 6weeks. These results suggest that APE has both suppressive and preventive potencies against hypercholesterolemia and has the potency to protect against lipid peroxidation.

Nitrogen removal from reject water with primary sludge as denitrification carbon source

A novel system was used for nitrogen removal from reject water. This system includes one anoxic/oxic reactor for nitrification and a special reactor for denitrification in which primary sludge was added intermittently as electron donor. In denitrification reactor, sludge fermentation and denitrification reaction took place simultaneously and promoted each other. It was found that effluent recycle could improve nitrogen removal efficiency due to reclaiming of alkalinity. Under steady state conditions, the average solid retention time (SRT) in denitrification reactor was 12-15 d, a total nitrogen loading rate was 0.2 kg N/(m(3) day) and TN removal efficiency was more than 90% without extra carbon source addition. Primary sludge was degraded so that volatile suspended solid (VSS) decreased by 50%. Further investigation showed that ORP could be taken as a control parameter for sludge addition.

Clonal analysis of gastric carcinoma and precancerous lesions and its relation to Ki-67 protein expression

The pathogenesis of intestinal carcinoma is characterized as progressing through multiple steps, which begin with atrophic gastritis followed by intestinal metaplasia, dysplasia and carcinoma. However, the clonal status of gastric precancerous lesions and its association with proliferative kinetics have not been fully understood. In this study, gastric lesions and normal epithelial cells were isolated from formalin-fixed paraffin embedded tissues using a laser capture microdissection (LCM) system, the clonality was analyzed with human androgen receptor gene (HUMARA) polymerase chain reaction (PCR), and the PCR products were examined using Applied Biosystems 3730 DNA Analyzer. The relationship between the clonal status and Ki-67 protein expression was also investigated. Ki-67 was detected by two-step immunohistochemical staining. 5/32 intestinal metaplasia lesions, 10/45 low grade intraepithelial neoplasia, 25/36 high grade intraepithelial neoplasia and 20/20 intestinal gastric carcinoma were of monoclonal origin. Similar to monoclonal inactivation, the expression rate of Ki-67 also increased along the multi-step gastric carcinogenesis. Clonal status was associated with the expression rate of Ki-67 to a certain extent, which may be useful in assessing susceptibility to gastric carcinoma. Key words: gastric carcinoma; precancerous lesion; clonal analysis; Ki-67.

New roughness parameter for the characterization of regularly textured or ordered patterned superhydrophobic surfaces

Surface geometry affects strongly superhydrophobic behavior. To characterize the effect, roughness as a comprehensive geometrical parameter is used, but this parameter in its general mathematic expression cannot reflect exactly such a geometrical effect, in particular, for the regularly textured or ordered patterned superhydrophobic surfaces. In this study, we propose a new parameter to mathematically describe roughness for such superhydrophobic surfaces. On the basis of this parameter, an ideal surface texture with the maximum roughness for achieving the superhydrophobicity is suggested, which is consistent with the previous experimental observations and theoretical considerations.

Identification of yeasts and evaluation of their distribution in Taiwanese Kefir and Viili starters

The objective of the present study was to investigate yeast communities in kefir grains and viili starters in Taiwan through conventional microbiological cultivation and polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE). The DNA sequencing was used as a validity technique to ensure that all isolates within each group belonged to just one species, and to confirm the identified results of PCR-DGGE. Results indicated that a combination of conventional microbiological cultivation with PCR-DGGE and sequencing could successfully identify 4 yeast species from both types of cultures in Taiwan. Kluyveromyces marxianus, Saccharomyces turicensis, and Pichia fermentans were found in Taiwanese kefir grains with a distribution of 76, 22, and 2%, respectively, whereas Klu. marxianus, Saccharomyces unisporus and P. fermentans were identified in viili starters corresponding to 58, 11, and 31% of the total cell counts, respectively. Furthermore, the culture-independent method was applied to identify the yeast species using DGGE. Only 2 yeast species, Klu. marxianus and S. turicensis, were found in kefir grains and 2, Klu. marxianus and P. fermentans, in viili starters. These results suggest that in samples containing multiple species, PCR-DGGE may fail to detect some species. Sequences of yeast isolates reported in this study have been deposited in the GenBank database under accession nos. DQ139802, AF398485, DQ377652, and AY007920.

Advanced nitrogen removal via nitrite from municipal wastewater in a pilot-plant sequencing batch reactor

To obtain economically sustainable wastewater treatment, advanced nitrogen removal from municipal wastewater and the feasibility of achieving and stabilizing short-cut nitrification and denitrification were investigated in a pilot-plant sequencing batch reactor (SBR) with a working volume of 54 m(3). Advanced nitrogen removal, from summer to winter, with effluent TN lower than 3 mg/L and nitrogen removal efficiency above 98% was successfully achieved in pulsed-feed SBR. Through long-term application of process control in pulsed-feed SBR, nitrite accumulation reached above 95% at normal temperature of 25 degrees C. Even in winter, at the lowest temperature of 13 degrees C, nitrite was still the end production of nitrification and nitrite accumulation was higher than 90%. On the basis of achieving advanced nitrogen removal, short-cut nitrification and denitrification was also successfully achieved. Compare to the pulse-feed SBR with fixed time control, the dosage of carbon source and energy consumption in pulsed-feed SBR with process control were saved about 30% and 15% respectively. In pulsed-feed SBR with process control, nitrogen removal efficiency was greatly improved. Moreover, consumption of power and carbon source was further saved.

Injury-related fatalities in China: an under-recognised public-health problem

The May 2008 earthquake in Wenchuan drew attention to the important but largely unrecognised public-health problem of injury-related mortality and morbidity in China. Injuries account for more than 10% of all deaths and more than 30% of all potentially productive years of life lost due to premature mortality in China. Traffic-related injuries (mainly among cyclists and pedestrians), suicide, drowning, and falls account for 79% of all injury deaths. Rural injury death rates are double those of urban rates and male rates are double those of female rates. Despite an 81% increase in the traffic-related mortality from 1987 to 2006-associated with rapid motorisation-the overall injury mortality decreased by 17%, largely due to a surprising (and unexplained) 57% reduction in the suicide rate. Low-cost prevention measures that are most likely to produce large reductions in injury deaths include enforcement of laws for drinking and driving and for seat belt and helmet use, restriction of access to the most potent pesticides, and teaching children to swim. China needs to improve monitoring of fatal and non-fatal injuries, promote intersectoral collaboration, build institutional capacities, and, most importantly, mobilise community support and political will for investment in prevention.

Essential oil from leaves of Cinnamomum osmophloeum acts as a xanthine oxidase inhibitor and reduces the serum uric acid levels in oxonate-induced mice

The xanthine oxidase (XOD) inhibitory activity and anti-hyperuricemia effect in mice of Cinnamomum osmophloeum, which is an endemic tree in Taiwan, were evaluated in this study. The results demonstrated that the essential oil of C. osmophloeum leaves presented the strongest XOD inhibition activity (IC(50)=16.3 μg/ml); however, no significant XOD inhibition activities were found in ethanolic and hot water extracts. Furthermore, among the main compounds of essential oil, the cinnamaldehyde exhibited the potent XOD inhibition activity with an IC(50)=8.4 μg/ml. Besides, the reducing serum uric acid levels in oxonate-induced mice by cinnamaldehyde were further investigated. The hyperuricemic mice were oral administrated cinnamaldehyde at a dosage of 150 mg/kg, the uric acid value in serum was reduced from 5.25±0.63 to 2.10±0.04 mg/dl, the levels of serum uric acid in mice was lowered down by 84.48% as compared to the hyperuricemic control group. Based on the results obtained in this study, cinnamaldehyde may be a potential lead compound for developing the pharmaceutic for anti-hyperuricemia agent.

Influence of wastewater composition on biological nutrient removal in UniFed SBR process

The effects of influent C/N ratio and C/P ratio on biological nutrient removal performance were investigated in a lab-scale UniFed SBR apparatus treating real domestic wastewater. The results showed that TN removal efficiency increased as C/N ratio increased from 43.6% at 2.8 to 80.8% at 5.7. But when C/N ratio increased further, TN removal efficiency increased very slowly. This was because when C/N ratio was higher than 5.7, complete denitrification in the sludge blanket during feed/decant period had been achieved, TN removal efficiency during this period always kept the maximum value and only TN removal efficiency during aeration period rose as C/N ratio increased. PO(4) (3-) removal efficiency increased as C/N ratio increased from 27.3% at 2.8 to 88.1% at 5.7. When C/N ratio was 6.5 and above, PO(4) (3-) concentration couldn't be detected in the effluent. When influent C/N ratio and volumetric exchange ratio were fixed at 6 and 33% respectively, as C/P ratio was higher than 33, PO(4) (3-) concentration of effluent always remained below the detection level and phosphorus removal efficiency kept stable at 100%, but as the C/P ratio was lower than 33, phosphorus removal efficiency increased as C/P ratio increased linearly. C/P ratio hardly affected TN removal efficiency, which always kept at 82.2%-85.8% in this study.

Intranasal delivery of T-bet modulates the profile of helper T cell immune responses in experimental asthma

BACKGROUND

Allergic asthma is caused by aberrant helper T (T(H)) type 2 immune responses in susceptible individuals, characterized by airway hyperresponsiveness, chronic airway inflammation, and mucus hypersecretion. Its prevalence continues to increase, but optimal treatment remains a challenge. The transcription factor T-bet is a master regulator of T(H)1 lineage commitment and strongly promotes interferon gamma expression during T(H)1 cell differentiation.

OBJECTIVE

The aim of this study was to explore the role of intranasal delivery of T-bet on the differentiation of T(H) cell subsets and airway inflammation in the ovalbumin (OVA)-induced mouse model of allergic airway inflammation.

METHODS

BALB/c mice were sensitized by intraperitoneal injection of OVA and challenged with nebulized OVA. Four days before the inhalation challenge, the sensitized mice were subjected to intranasal delivery of a recombinant adeno-associated virus vector carrying murine T-bet gene (AAV-T-bet). Expression of the transcription factors T-bet, GATA3, and Foxp3 was then assayed in the lungs, and airway histology was analyzed along with other inflammatory parameters, such as eosinophils and cytokines in bronchoalveolar lavage (BAL) fluid, and total and OVA-specific immunoglobulin (Ig) E in serum.

RESULTS

Intranasal administration of AAV-T-bet efficiently balanced the T(H)1/T(H)2 transcription factor and cytokine profile and significantly decreased the number of eosinophils in BAL fluid. It also resulted in a reduction of peribronchial inflammation scores and serum IgE levels in OVA-sensitized and challenged mice during the effector phase.

CONCLUSIONS

Our data show that intranasal delivery of T-bet can promote a T(H)1 immune response, restore a balanced Th immune response, and inhibit airway inflammation during the challenge phase in a mouse model of allergic airway inflammation.

Electric field enhancement between two Si microdisks

The field enhancement in the gap between two Si microdisks is theoretically investigated using the finite difference time domain method. We show that the electric field within this gap increases as the distance between the two disks decreases, and it can be enhanced by as much as two orders of magnitude. By perturbing the Si microdisks to force the field leakage into an ever smaller volume, the field enhancement can reach a value as high as 238 with a deep sub-wavelength mode volume. This behavior is comparable to what can be observed in gap plasmons between metal nanoparticles, but is produced here in purely dielectric structures.

The effect of Al/Si ratio on the transport properties of the layered intermetallic compound CaAl(2)Si(2)

We report the results of the electrical resistivity and Seebeck coefficient as well as thermal conductivity measurements on the stoichiometric CaAl(2)Si(2) and non-stoichiometric CaAl(1.75)Si(2.25), CaAl(1.9)Si(2.1), CaAl(2.1)Si(1.9), and CaAl(2.25)Si(1.75) compounds in the temperature range 10-300 K. It has been found that the magnitude of electrical resistivity decreases for the non-stoichiometric samples, attributed to the shift of Fermi energy from the dip of the density of states as a consequence of the changed Si/Al content. In addition, a systematic change in the magnitude of Seebeck coefficient as a function of Al/Si concentration has been observed. The results have been associated with the effect of hole/electron doping on the Fermi level density of states. A detailed analysis of the electrical resistivity and Seebeck coefficient suggests the presence of two types of charge carrier and the temperature dependent changes in their mobility. From the thermal conductivity results, we correlated the extent of disorder and Al/Si ratio with various thermal scattering mechanisms in the investigated temperature range.

Fidelity of bacterial source tracking: Escherichia coli vs Enterococcus spp and minimizing assignment of isolates from nonlibrary sources

AIMS

The goal of the study was to improve the fidelity of library-dependent bacterial source tracking efforts in determining sources of faecal pollution. The first objective was to compare the fidelity of source assignments using Escherichia coli vs Enterococcus spp. The second objective was to determine the efficacy of using thresholds during source assignments to reduce the rate of misassignments when nonlibrary isolates (i.e. isolates from animals not used in building the identification library) are present.

METHODS AND RESULTS

E. coli and Enterococcus isolates from 784 human, cow, deer, dog, chicken, and gull faecal samples were fingerprinted using BOX-PCR. Jack-knife analysis of the fingerprints showed that the overall rate of correct assignment (ORCA) of 867 E. coli isolates was 67% compared with 82% for 1020 Enterococcus isolates. In a separate blind test using similarity value and quality factor thresholds, the ORCA of 130 E. coli and 131 Enterococcus isolates were 70% and 98%, respectively. The use of these thresholds reduced misassignment of 262 nonlibrary enterococcal isolates from horses, goats, pigs, bats, squirrels, ducks, geese, and migratory song birds. Misassignment was reduced from 100% when thresholds were not used, to 47% using similarity threshold alone, and to 12% when both thresholds were used.

CONCLUSIONS

The use of enterococci provides higher rates of correct source assignment compared with E. coli. The use of similarity thresholds to decide whether to accept source assignments made by computer programmes reduces the rate of misassignment of nonlibrary isolates.

SIGNIFICANCE AND IMPACT OF THE STUDY

Although both E. coli and Enterococcus spp. are still used in microbial source tracking, the use of enterococci should be preferred over the use of E. coli in DNA fingerprint-based efforts. In addition, because environmental isolates are not limited to those from animals used to build source tracking libraries, similarity thresholds should be used during source assignments to reduce the rate of misassignments.

Detection of the nifH gene of Methanobrevibacter smithii: a potential tool to identify sewage pollution in recreational waters

AIMS

The goal of this study was to develop and test the efficacy of a PCR assay for the environmental detection of the nifH gene of Methanobrevibacter smithii, a methanogen found in human faeces and sewage.

METHODS AND RESULTS

PCR primers for the nifH gene of M. smithii were designed, tested and used to detect the presence or absence of this organism in faecal and environmental samples. Specificity analysis showed that the Mnif primers amplified products only in M. smithii pure culture strains (100%), human faeces (29%), human sewage samples (93%) and sewage-contaminated water samples (100%). No amplification was observed when primers were tested against 43 bacterial stock cultures, 204 animal faecal samples, 548 environmental bacterial isolates and water samples from a bovine waste lagoon and adjacent polluted creek. Sequencing of PCR products from sewers demonstrated that a 222-bp product was the nifH gene of M. smithii. The minimal amount of total DNA required for the detection of M. smithii was 10 ng for human faeces, 10 ng for faecally contaminated water and 5 ng for sewage. Recreational water seeded with M. smithii established a lower detection limit of 13 cells ml(-1).

CONCLUSIONS

The Mnif assay developed during this investigation showed successful detection of M. smithii in individual human faecal samples, sewage and sewage-contaminated water but not in uncontaminated marine water or bovine-contaminated waters. The Mnif assay appears to be a potentially useful method to detect sewage-polluted coastal waters.

SIGNIFICANCE AND IMPACT OF THE STUDY

This study was the first to utilize methanogens as an indicator of sewage pollution. Mnif PCR detection of M. smithii was shown to be a rapid, inexpensive and reliable test for determining the presence or absence of sewage pollution in coastal recreational waters.

Immunocapture UPPCR combined with DGGE for rapid detection of Shigella species

AIMS

To develop an immunocapture universal primer PCR (iUPPCR) combined with denaturing gradient gel electrophoresis (DGGE) and evaluate it as a method permitting rapid detection of Shigella species and their serotypes.

METHODS AND RESULTS

This method amplifying the conserved regions of bacterial 16S rRNA genes of different species or serotypes of Shigella dysentery bacilli captured and enriched by polyvalent antibodies can detect and distinguish causative pathogens rapidly. Four serotypes from three Shigella species including Shigella dysenteriae serotype 1, Shigella boydii serotype 1, Shigella flexneri serotypes 1a and 3a were examined.

CONCLUSION

Our approach could be adopted for not only axenic bacterial population but also mixed communities and achieve rapid detection of various bacteria from the same genus or species in one sample.

SIGNIFICANCE AND IMPACT OF THE STUDY

The iUPPCR-DGGE method was shown to be more convenient than serotype-specific-antibody-based method of iUPPCR for Shigella species detection and it could be also applied to the quick detection for other kinds of pathogens with many serotypes.

Molecular cloning and structural analysis of the gene encoding Bacillus cereus exochitinase Chi36

The chi36 gene encoding exochitinase Chi36 was cloned from a Bacillus cereus 6E1 subgenomic library. The chi36 open reading frame is 1080 bp long encoding a Chi36 precursor protein of 360 amino acids, consisting of a 27 amino acid N-terminal signal peptide and a 333 amino acid sequence found in the mature Chi36 protein of 36.346 kDa. Chi36 shows significant amino acid sequence similarity to many bacterial chitinases, but has highest similarity to B. circulans WL-12 chitinase D. Chi36 belongs to subfamily B of bacterial chitinases in family 18 of glycosyl hydrolases. Chi36 shows a simple and compact structural organization composed of an N-terminal signal peptide and a C-terminal (beta/alpha)8-barrel catalytic domain (CaD). The Chi36 signal peptide is recognized by Escherichia coli, allowing Chi36 secretion. Chi36 is the first one-domain (CaD) bacterial chitinase cloned from B. cereus.

Improved pattern transfer in nanoimprint lithography at 30 nm half-pitch by substrate-surface functionalization

Resist detachment from the substrate during mold-substrate separation is one of the key challenges for nanoimprint lithography as the pitch of features decreases. We analyzed the problem by considering the surface and interfacial free energies of the initial state and the possible final states of the mold-polymer-substrate system and designed the chemistry of the system to provide the desired final state. We dramatically improved the resist adhesion to the substrate by assembling a monolayer of surface linker molecules on the substrate surface. A 37 nanowire pattern at 30 nm half-pitch was imprinted onto the surface-modified substrate.

Pilot-scale studies on biological treatment of hypersaline wastewater at low temperature

In order to investigate the feasibility of biological treatment of hypersaline wastewater produced from toilet flushing with seawater at low temperature, pilot-scale studies were established with plug-flow activated sludge process at low temperature (5-9 degrees C) based on bench-scale experiments. The critical salinity concentration of 30 g/L, which resulted from the cooperation results of the non-halophilic bacteria and the halophilic bacteria, was drawn in bench-scale experiments. Pilot-scale studies showed that high COD removal efficiency, higher than 80%, was obtained at low temperature when 30 percent seawater was introduced. The salinity improved the settleability of activated sludge, and average sludge value dropped down from 38% to 22.5% after adding seawater. Seawater salinity had a strong negative effect on notronomonas and nitrobacter growth, but much more on the nitrobacter. The nitrification action was mainly accomplished by nitrosomonas. Bench-scale experiments using two SBRs were carried out for further investigation under different conditions of salinities, ammonia loadings and temperatures. Biological nitrogen removal via nitrite pathway from wastewater containing 30 percent seawater was achieved, but the ammonia removal efficiency was strongly related not only to the influent ammonia loading at different salinities but also to temperature. When the ratio of seawater to wastewater was 30 percent, and the ammonia loading was below the critical value of 0.15 kgNH4+-N/(kgMLSS.d), the ammonia removal efficiency via nitrite pathway was above 90%. The critical level of ammonia loading was 0.15, 0.08 and 0.03 kgNH4+-N/(kgMLSS.d) respectively at the different temperature 30 degrees C, 25 degrees C and 20 degrees C when the influent ammonia concentration was 60-80 mg/L and pH was 7.5-8.0.

Ileal herniation into a sigmoid colon epiploic fat foramen extrasigmoid hernia

Internal abdominal hernia (IAH) is defined as protrusion of viscus through a peritoneal or mesenteric aperture, leading to its encapsulation within another compartment in the abdominal cavity. Herein we report a rare case of small bowel obstruction due to herniation with incarceration of a loop of ileum into a foramen formed by the epiploic fat of the sigmoid colon due to a non-specific inflammatory process; this may be defined as extrasigmoid hernia. To our knowledge, there has been no previous report of this type of IAH in the English literature. In summary, an acute intestinal obstruction with strangulation in the absence of an external hernia without previous operation suggests the possibility of internal hernia, especially if the patient has a history of intermittent abdominal distress.

EDAG regulates the proliferation and differentiation of hematopoietic cells and resists cell apoptosis through the activation of nuclear factor-κB

Erythroid differentiation-associated gene (EDAG) is considered to be a human hematopoiesis-specific gene. Here, we reported that downregulation of EDAG protein in K562 cells resulted in inhibition of growth and colony formation, and enhancement of sensitivity to erythroid differentiation induced by hemin. Overexpression of EDAG in HL-60 cells significantly blocked the expression of the monocyte/macrophage differentiation marker CD11b after pentahydroxytiglia myristate acetate induction. Moreover, overexpression of EDAG in pro-B Ba/F3 cells prolonged survival and increased the expression of c-Myc, Bcl-2 and Bcl-xL in the absence of interleukin-3 (IL-3). Furthermore, we showed that EDAG enhanced the transcriptional activity of nuclear factor-kappa B (NF-kappa B), and high DNA-binding activity of NF-kappa B was sustained in Ba/F3 EDAG cells after IL-3 was withdrawn. Inhibition of NF-kappa B activity resulted in promoting Ba/F3 EDAG cells death. These results suggest that EDAG regulates the proliferation and differentiation of hematopoietic cells and resists cell apoptosis through the activation of NF-kappa B.

Nitrite accumulation by aeration controlled in sequencing batch reactors treating domestic wastewater

The feasibility of obtaining and keeping stable nitrite accumulation in Sequencing Batch Reactors (SBRs) treating domestic wastewater is studied. The final product of ammonium oxidation is either reproducible nitrate or nitrite depending on the aeration strategy. With the aerobic-anoxic sequence, two SBRs fed with domestic wastewater are operated in parallel. One SBR (SBR1) is controlled by the aeration control strategy, and the other SBR (SBR2) by alternate aeration control strategy. Based on the on-line indirect measurements of DO and pH, the relationship between pH (or DO) and nitrogen concentration (NH4+-N, NO(3-)-N and NO(2-)-N) is investigated. The result indicates that pH and DO can be used as control parameters for the real-time aeration control strategy to obtain nitritation in SBR treating domestic wastewater. The result of SBR1 indicates that long-term stable nitritation is possible at 32+/-1 degrees C. The result of SBR2 indicates that the aeration control strategy is necessary for nitritation during the acclimation period, because the nitrite accumulation disappears when the aeration is extended.

Phosphorus removal under anoxic conditions in a continuous-flow A2N two-sludge process

The Anaerobic-Anoxic/Nitrification (A2N) system is a continuous-flow, two-sludge process in which Poly-P bacteria are capable of taking up phosphate under anoxic conditions using nitrate as an electron acceptor. The process is very efficient because it maximizes the utilization of organic substrate for phosphorus and nitrogen removal. An experimental lab-scale A2N system fed with domestic sewage was tested over a period of 260 days. The purpose of the experiment was to examine phosphorus removal capacity of a modified A2N two-sludge system. Factors affecting phosphorus and nitrogen removal by the A2N system were investigated. These factors were the influent COD/TN ratio, Sludge Retention Time (SRT), Bypass Sludge Flow rate (BSF) and Return Sludge Flow rate (RSF). Results indicated that optimum conditions for phosphorus and nitrogen removal were the influent COD/TN ratio around 6.49, the SRT of 14 days, and the BSF and RSF were fixed at about 26-33% of influent flow rate.

Nitrification-denitrification via nitrite for nitrogen removal from high nitrogen soybean wastewater with on-line fuzzy control

This study is to demonstrate the performance of a new technology for complete nitrogen removal from soybean wastewater with high nitrogen concentrations. Nitrification-denitrification via nitrite was performed in three kinds of operating condition, i.e. nitrification-denitrification via nitrite under traditional SBR process, nitrification-denitrification via nitrite by alternating oxic/anoxic under fixed-time control and nitrification-denitrification via nitrite by alternating oxic/anoxic under on-line fuzzy control. The best one is nitrification-denitrification via nitrite by alternating oxic/anoxic under on-line fuzzy control. It not only improves both nitrification and denitrification rates and decreases total reaction time, but also saves the amount of added carbon source and alkalinity. In addition, reaction time can be shortened and operation cost can be saved by using real-time fuzzy control aeration and mixing time. So this method enhances the efficiency and the stability of nitrogen removal, and reduces operating costs and construction investment in the process of wastewater treatment.

Nitrogen removal from pharmaceutical manufacturing wastewater with high concentration of ammonia and free ammonia via partial nitrification and denitrification

In this study, laboratory-scale experiments were conducted applying a Sequencing Batch Reactor (SBR) activated sludge process to a wastewater stream from a pharmaceutical factory. Nitrogen removal can be achieved via partial nitrification and denitrification and the efficiency was above 99% at 23 degrees C+/-1. The experimental results indicated that the nitrite oxidizers were more sensitive than ammonia oxidizers to the free ammonia in the wastewater. The average accumulation rate of nitrite was much higher than that of nitrate. During nitrogen removal via the nitrite pathway, the end of nitrification and denitrification can be exactly decided by monitoring the variation of pH. Consequently, on-line control for nitrogen removal from the pharmaceutical manufacturing wastewater can be achieved and the cost of operation can be reduced.

Influence of ORP variation, carbon source and nitrate concentration on denitrifying phosphorus removal by DPB sludge from dephanox process

The effect of added carbon source and nitrate concentration on the denitrifying phosphorus removal by denitrifying phosphorus removal bacteria sludge was systematically studied using batch experiments, at the same time the variation of ORP was investigated. Results showed that the denitrifying and phosphorus uptake rate in the anoxic phase increased with the high initial anaerobic carbon source addition. However, once the initial COD concentration reached a certain level, which was in excess of the PHB saturation of Poly-p bacteria, residual COD carried over to the anoxic phase inhibited the subsequent denitrifying phosphorus uptake. This was equal to supplementing the external carbon source to the anoxic phase, furthermore the higher the external carbon source concentration the more powerful the inhibition caused. High nitrate concentration in the anoxic phase increased the initial denitrifying phosphorus rate. Oncethe nitrate was exhausted, phosphate uptake changed to phosphate release. Moreover, the time of this turning point occurred later with the higher nitrate addition. On the other hand, through on-line monitoring the variation of the ORP with different initial COD concentration, it was found that ORP could be used as a control parameter for phosphorus release, but it is impossible to utilize ORP for controlling the dinitrification and anoxic phosphorus uptake operations.

Analysis of complement-bound hepatitis B virus complexes by an immuno-capture polymerase chain reaction method

Hepatitis B Virus (HBV) can be present in the circulating blood either as a free virus or as a virion-immunoglobulin (Ig) complex with or without complement. However, information regarding the complement-bound HBV circulating immune complexes (CIC) in HBV-infected patients is currently not available. In the present study, we have combined immuno-capture and polymerase chain reaction (PCR) and developed a quick method of high specificity for the detection of complement-bound HBV CIC. We found that the frequency of HBV-factor B was associated with clinical types of hepatitis B (HB) but not with that of HBV-C1q. Moreover, increased frequency at P < 0.05 were found for HBV/C1q-CIC in the group with normal total bilirubin (TBIL) and for HBV/factor B-CIC in the group with positive hepatitis B e antigen (HBeAg). These findings suggest that the immuno-capture PCR (iPCR) for the detection of HBV-bound CIC is a valuable method for analysis of the composition of the immune complexes and for the understanding of host immune response and immune pathogenesis in HBV-infected individuals. In summary, iPCR is a valuable method for analysis of the composition of the immune complexes, which may provide new and valuable insights into HBV pathogenesis.

Methanethiosulfonate-modification alters local anesthetic block in rNav1.4 cysteine-substituted mutants S1276C and L1280C

We previously showed that lysine substitutions at two residues in segment 6 of domain 3 in voltage-gated Na(+) channel rNav1.4 (S1276K, L1280K) reduced steady-state inactivated local anesthetic block. Here we studied cysteine substitutions at the same residues (S1276C, L1280C). We used whole-cell recordings to determine local anesthetic block (100 microM bupivacaine) before and after cysteine modification with 1.5 mM 2-aminoethyl methanethiosulfonate (MTSEA). Compared with rNav1.4, steady-state resting bupivacaine block at -180 mV was increased in S1276C, while inactivated block at -50 mV was not different in the mutants. After application of MTSEA at -160 mV, rNav1.4 showed enhanced bupivacaine block and a negative shift in V(1/2) of the bupivacaine affinity curve, while L1280C and S1276C showed a decrease in inactivated bupivacaine block after MTSEA. Application of MTSEA at 0 mV produced similar results in rNav1.4 and L1280C, but an opposite effect in S1276C, i.e., enhancement of bupivacaine block, with a large negative shift in V(1/2) of the bupivacaine affinity curve similar to that found in rNav1.4. We conclude that 1) MTSEA modification of 1276C or 1280C decreases inactivated bupivacaine block similar to that found in L1280K and S1276K, 2) residue 1276C is only accessible to MTS-modification in the resting state, and 3) MTSEA may modify a native cysteine in rNav1.4 that produces an allosteric, indirect effect on bupivacaine affinity.

Analysis of hepatitis B virus-immunoglobulin isotype complexes by a novel immuno-capture polymerase chain reaction method

Hepatitis B virus (HBV) can be present in the circulating blood either as free virus or as a virion-immunoglobulin (Ig) complex. Presently, it remains unclear what specific role each Ig plays in the clearance of HBV. In this study, a novel method that combined immuno-capture and polymerase chain reaction (PCR) amplification was used for detecting and distinguishing different HBV-Ig complexes. Three isotypes of Ig (IgM, IgG and IgA) bound to HBV were detected in the four clinically defined stages of HBV infection in 108 patients. The results showed that all the three isotypes of Ig could bind to HBV, and the patterns of HBV-Ig complexes varied according to disease categories. Interestingly, the frequency of HBV DNA-Ig complexes in hepatitis B e antigen (HBeAg)-positive patients was significantly lower than that in HBeAg-negative patients. All the data suggest that the three isotypes of HBV DNA-Ig circulating immune complex (CIC) may have different biological meanings. In summary, HBV bound to an antibody is a common feature of hepatitis B, and immuno-capture PCR is a valuable method for the analysis of the composition of the immune complexes. The detection of HBV-Ig complexes may provide new and valuable insights into HBV pathogenesis.

Use of pH as fuzzy control parameter for nitrification under different alkalinity in SBR process

In order to achieve fuzzy control of nitrification in a Sequencing Batch Reactor (SBR) brewery wastewater was used as the substrate. The effect of alkalinity on pH variation during nitrification was systematically studied, at the same time the variations of DO and ORP were investigated. Alkalinity and pH of the wastewater were adjusted by adding sodium bicarbonate at five levels and sodium hydroxide at two levels. Unadjusted wastewater was also studied. According to the results, variation of pH could be divided into rising type and descending type. When bicarbonate alkalinity was deficient or sufficient, the descending type happened. If alkalinity was deficient, the pH decreasing rate got slower when nitrification nearly stopped; if alkalinity was sufficient, at the end of nitrification pH turned from decrease to increase. This was the most common situation and pH could be used to control the end of nitrification. When alkalinity was excessive, the rising type happened, pH was increasing at nearly a constant rate during and after nitrification and could not be used to control the nitrification time, but if the aeration rate was moderate DO could be used to control the nitrification time. This situation seldom happened. Therefore the variation of pH could not only be used to control the nitrification time but also to judge whether the alkalinity was enough or not. On the basis of this, the fuzzy controller of nitrification in SBR was constructed. When discussing the influence of pH on nitrification rate the composition and concentration of alkalinity must be considered or else the results may be incomprehensive. And to some extent the influence of alkalinity on nitrification rate was more important than pH.

Analysis of complement-bound HCV complexes using a novel immuno-capture RT-PCR method

Recently, more and more evidence has supported the hypothesis that liver cell injury was immune-mediated in patients with hepatitis C virus (HCV) infection, and that circulating immune complexes (CICs) might play a role in the pathogenesis of chronic hepatitis C (HC). In the present study, we have combined immuno-capture and reverse transcriptase-polymerase chain reaction (RT-PCR), and developed a quick method of high specificity for the detection of complement-bound HCV-CIC. We found that there were higher frequencies of HCV-C1q CIC than that of HCV-factor B, and there was a deviation of complement from immunoglobulin (Ig) in HCV-CIC. These findings suggest that immuno-capture RT-PCR (iRT-PCR) for the detection of HCV-bound CIC is a valuable method for the analysis of the composition of the immune complexes, and for the understanding of host immune response and immune pathogenesis in HCV-infected individuals.

Modifications of human cardiac sodium channel gating by UVA light

Voltage-gated Na(+) channels are membrane proteins responsible for the generation of action potentials. In this report we demonstrate that UVA light elicits gating changes of human cardiac Na+ channels. First, UVA irradiation hampers the fast inactivation of cardiac Nav1.5 Na(+) channels expressed in HEK293t cells. A maintained current becomes conspicuous during depolarization and reaches its maximal quasi steady-state level within 5-7 min. Second, the activation time course is slowed by UVA light; modification of the activation gating by UVA irradiation continues for 20 min without reaching steady state. Third, along with the slowed activation time course, the peak current is reduced progressively. Most Na(+) currents are eliminated during 20 min of UVA irradiation. Fourth, UVA light increases the holding current nonlinearly; this phenomenon is slow at first but abruptly fast after 20 min. Other skeletal muscle Nav1.4 isoforms and native neuronal Na(+) channels in rat GH(3) cells are likewise sensitive to UVA irradiation. Interestingly, a reactive oxygen metabolite (hydrogen peroxide at 1.5%) and an oxidant (chloramine-T at 0.5 mM) affect Na(+) channel gating similarly, but not identically, to UVA. These results together suggest that UVA modification of Na(+) channel gating is likely mediated via multiple reactive oxygen metabolites. The potential link between oxidative stress and the impaired Na(+) channel gating may provide valuable clues for ischemia/reperfusion injury in heart and in CNS.

Analysis of HCV-immunoglobulin isotype complexes provide new insights into antibody response to HCV

Hepatitis C virus (HCV) is known for its ability to establish persistent infection and cause chronic hepatitis in most infected individuals. The antibody response to HCV in HCV-circulating immune complexes (CIC) is unknown. In the present study, we have characterized distinct changes in patterns of HCV-immunoglobulin (Ig) constituents with disease category, viral mutation and clinical markers. The number of samples positive for single HCV-Ig, HCV-IgG and HCV-IgA, HCV-IgM and HCV-IgA, HCV-IgM and HCV-IgG, HCV-IgM, HCV-IgG and HCV-IgA in 47 samples tested were 8 (17%), 1 (2.1%), 9 (19.1%), 4 (8.5%) and 17 (36.2%), respectively. The occurrence of HCV-IgM and HCV-IgA in combination of two isotypes of HCV-Ig became predominant. These results show that defective IgG in HCV-CIC may contribute to long-term viremia. Further analysis indicated that the frequency of HCV RNA/IgA-CIC in the abnormal aspartic aminotransferase (AST) group was significantly higher than that of the normal AST group, and HCV RNA/IgA-CIC frequency in the abnormal alanine aminotransferase (ALT) group was slightly higher than that in the normal ALT group. IgA complexes may reflect the damage degree of liver function during the course of HCV infection. We also found that there were more mutations in supernatant than in other constituents from single-strand conformation polymorphism (SSCP) analysis. Our results suggest that Ig-complexed virions and free virions may have different biological consequences, with the latter being elusive to immunological elimination. The findings in this study may provide some new insights into antibody response to HCV.

Isolation and Characterization of EDAG-1, A Novel Gene Related to Regulation in Hematopoietic System

A novel gene, named embryonic develop associated gene 1 ( EDAG -1) and abundantly expressed in human fetal liver tissues, was isolated by screening a human fetal liver cDNA library and the 5' RACE. The full length of EDAG-1 mRNA is 2 166 bp, with an open reading frame of 1 452 bp neucleotides, encoding a 484 amino acid protein. No domain or motif was found similar with other genes by Blast program. Two copies of AUUUA motif in 3' non-translated region show instability of its mRNA. The molecular weight of the protein is 55.3 kD identified by the translation in vitro. EDAG-1 is specifically expressed in hematopoietic tissues, and is quickly down-regulated during the differentiation of K562 cells induced by hemin and EPO. These results show that EDAG-1 is related to the regulation in hematopoietic system and the development of leukemia.