Effect of C/N ratio on extracellular polymeric substances of activated sludge from an anoxic-aerobic sequencing batch reactor treating saline wastewater

The effect of C/N ratio on extracellular polymeric substances (EPS) of activated sludge was investigated in an anoxic-aerobic sequencing batch reactor (SBR) treating saline wastewater. The protein (PN) and protein/polysaccharide (PN/PS) ratio in the loosely bound EPS (LB-EPS) increased with the decrease of C/N ratio, whereas the PS in the LB-EPS decreased. The PS, PN and PN/PS ratio in the tightly bound EPS (TB-EPS) were independent of C/N ratio. Two fluorescence peaks in the LB-EPS and TB-EPS were identified at excitation/emission (Ex/Em) wavelengths of 275-280/335-340 nm and 220-225/330-340 nm by three-dimensional excitation-emission matrix (3D-EEM) fluorescence spectroscopy, respectively. These peaks in LB-EPS and TB-EPS were, respectively, associated with tryptophan protein-like substances and aromatic protein-like substances. The tryptophan protein-like fluorescence peaks in LB-EPS showed blue shift along the Ex axis and red shift along the Em axis with the decrease of C/N ratio. Fourier transform infrared spectra suggested that the variation of C/N ratio had more distinct effect on the functional groups of protein in the LB-EPS than those in the TB-EPS. The sludge volume index value decreased with the increase of LB-EPS, but there was no correlation between SVI and TB-EPS.

Hollow metallic waveguides integrated with terahertz quantum cascade lasers

We present the realization of a compact, monolithically integrated arrangement of terahertz quantum cascade lasers with hollow metallic cylindrical waveguides. By directly mounting a copper pipe to the end facet of a double metal waveguide, it was possible to significantly improve the far field emission from such a sub-wavelength plasmonic mode, while preserving the characteristic performance of the laser. Careful alignment of the quantum cascade laser and the hollow waveguide is required in order to prevent the excitation of higher order/mixed modes as predicted with a high degree of accuracy by a theoretical model. Finally, this approach proved to be a superior method of beam shaping when compared to other in situ arrangements, such as a silicon hyper-hemispherical lens glued to the facet, which are presented.

Perchlorate reduction by hydrogen autotrophic bacteria in a bioelectrochemical reactor

The autotrophic hydrogen reduction of perchlorate was investigated in batch modes in a proton-exchange membrane bioelectrochemical reactor. The phylogenic characterization of hydrogen-autotrophic perchlorate-reducing cultures in the cathode cell mainly included the genera Aureibacter tunicatorum, Fulvivirga kasyanovii, Thermotalea metallivorans (T), bacterium WHC2-6, and Thauera sp. Q20-C. The suitable H2SO4 supplement concentration was identified to be between 0.04 and 0.05 mol L(-1) in the anode cell. The perchlorate reduction was affected by the sludge concentration in the cathode cell, current intensity, and initial perchlorate concentration. The removal efficiency of perchlorate positively correlated with the current intensity, and the current intensity of 20, 40, 50, and 60 mA corresponded to removal efficiencies of 95.03, 96.29, 97.56 and 98.99%, respectively. When the current intensity was sufficient for hydrogen production, the kinetics of the perchlorate reduction conformed to a zero-order kinetics model, and the maximum specific substrate utilization rates for perchlorate (Vmax) ranged from 5.52 to 14.34 mg ClO4(-) g(-1) volatile suspended solid (VSS) h(-1).

A novel way to statistically analyze morphologic changes in Dmp1-null osteocytes

Recent studies have revealed multiple roles of osteocytes in bone metabolism. However, detailed analyses of the embedded osteocytes in bone structure are still limited because of the high mineral content around these cells. In this study, we developed an innovative technique, the "FITC-Imaris technique", which combines FITC ([2, 5]-Fluorescein isothiocyanate), confocal microscopy and Imaris software. With this method, we could not only visualize the 3-D morphology of embedded osteocytes, but more importantly, we were able to statistically quantitate the osteocyte structure in the cell surface area, total cell volume, and dendrite numbers. Furthermore, we made a side-by-side comparison of the new method with the acid-etched SEM imaging technique, a common imaging method for studies of osteocyte morphology with a much smaller cell depth (< 3 μm). Finally, we used the FITC-Imaris technique to show both the morphological and statistical differences in the osteocyte structure between the Dmp1-null mice (the osteomalacia model) and their age-matched control littermates. We expect that this newly developed technique will become a powerful tool to disclose more roles that osteocytes play in bone health and diseases.

The -675 4G/5G polymorphism in the PAI-1 gene may not contribute to the risk of PCOS

OBJECTIVE

The association between the -675 4G/5G polymorphism in PAI-1 gene and PCOS has been studied with inconclusive results. We sought to investigate this inconsistency by performing a comprehensive meta-analysis on the polymorphism.

MATERIALS AND METHODS

Searches were performed in the PubMed, Embase, CNKI and Wanfang databases, covering all papers. Statistical analysis was performed using Revman5.2 and STATA11.0 software. A total of 11 case-control studies were extracted on the polymorphism involving 1861 PCOS cases and 1187 controls.

RESULTS

The results showed that, no significant increased/decreased risk were found for the polymorphism for PCOS: OR = 1.03, 95% CI = 0.77-1.66, p = 0.52 for 4G4G + 4G5G vs. 5G5G; OR = 0.99, 95% CI = 0.66-1.49, p = 0.96 for 4G4G vs. 5G5G + 4G5G; OR = 1.08, 95% CI = 0.66-1.79, p = 0.76 for 4G4G vs. 5G5G; OR = 1.11, 95% CI = 0.78-1.58, p = 0.56 for 4G5G vs. 5G5G; OR = 1.00, 95% CI = 0.71-1.41, p = 0.99 for 4G vs. 5G. In the further subgroup analysis by ethnicity, we did not find a significant association between the polymorphism for PCOS risk in either Asians or Europeans.

CONCLUSIONS

Our findings demonstrated that -675 4G/5G polymorphism in the PAI-1 gene might not be a risk factor for the development of PCOS.

Remote monitoring of nuclear power plants in Baden-Wuerttemberg

As part of its responsibilities as nuclear supervisory authority, the Ministry of the Environment, Climate Protection and the Energy Sector Baden-Wuerttemberg (UM) operates a computer-based system for remote monitoring of nuclear power plants (NPPs) (KFUe, Kernreaktor-Fernüberwachung). In addition to the Baden-Wuerttemberg NPPs located at Philippsburg, Neckarwestheim and the disused Obrigheim, those in foreign locations close to the border area, i.e. Fessenheim in France, and Leibstadt and Beznau in Switzerland, are monitored. The KFUe system provides several methods to evaluate and present the measured data as well as to ensure compliance of threshold limits and safety objectives. For the UM, it serves as an instrument of the nuclear supervision. In case of a radioactive release, the authorities responsible for civil protection can use dispersion calculations in order to identify potentially affected areas and to initiate protective measures for the population. Beyond the data collected at the plant sites, various international radiation and meteorological measuring networks are integrated in the KFUe. The State Institute for Environment, Measurements and Nature Protection (LUBW), the technical operator of the KFUe, runs its own special monitoring network for ambient gamma dose rate and nuclide specific activity concentration measurements in the vicinity of each NPP. This article gives an overview of the solution to combine data of different sources on a single screen: dose rate networks, dose rate traces measured by car, airborne gamma spectra of helicopters, mobile dose rate probes, grid data of weather forecasts, dispersion calculations, etc.

Enhancing glass-forming ability via frustration of nano-clustering in alloys with a high solvent content

The glass-forming ability (GFA) of alloys with a high-solvent content such as soft magnetic Fe-based and Al-based alloys is usually limited due to strong formation of the solvent-based solid solution phase. Herein, we report that the GFA of soft magnetic Fe-based alloys (with >70 at.% Fe to ensure large saturation magnetization) could be dramatically improved by doping with only 0.3 at.% Cu which has a positive enthalpy of mixing with Fe. It was found that an appropriate Cu addition could enhance the liquid phase stability and crystallization resistance by destabilizing the α-Fe nano-clusters due to the necessity to redistribute the Cu atoms. However, excessive Cu doping would stimulate nucleation of the α-Fe nano-clusters due to the repulsive nature between the Fe and Cu atoms, thus deteriorating the GFA. Our findings provide new insights into understanding of glass formation in general.

Elevated plasma sphingomyelin (d18:1/22:0) is closely related to hepatic steatosis in patients with chronic hepatitis C virus infection

Hepatic steatosis affects disease progression in patients with chronic hepatitis C virus (HCV) infection. We investigated the plasma sphingolipid profile in patients with chronic hepatitis C (CHC) and whether there was an association between HCV-related steatosis and plasma sphingolipids. We used high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) to analyze plasma sphingolipids in 120 interferon-naïve, non-diabetic, and non-obese CHC patients. Hepatic steatosis was defined as ≥5 % hepatocytes with fat based on histopathological analysis. Blood biochemical indicators and HCV load and genotype were also determined. Thirty-six (30.0 %) of 120 patients presented with hepatic steatosis Grades 1-3. Forty-four plasma sphingolipids were detected. Plasma sphingomyelin (SM) (d18:1/22:0) and ceramide (Cer) (d18:1/24:0)-1-P correlated with steatosis grade (r = 0.22, p = 0.015; r = -0.23, p = 0.012, respectively). SM (d18:1/22:0) [odds ratio (OR) = 1.12] and Cer (d18:1/24:0)-1-P (OR = 0.88) were independent factors for the presence of hepatic steatosis in CHC patients. The area under the curve (AUC) of SM (d18:1/22:0) and Cer (d18:1/24:0)-1-P was 0.637 and 0.638, respectively, to identify the presence of steatosis. Further analysis for genotype 2 CHC showed that only SM (d18:1/22:0) was independently linked to steatosis (OR = 1.21). The AUC of SM (d18:1/22:0) to identify hepatic steatosis in genotype 2 CHC was 0.726. Its sensitivity and negative predictive value reached 0.813 and 0.886, respectively. This study suggested that altered plasma SM (d18:1/22:0) was closely related to hepatic steatosis in chronic HCV infection, especially with genotype 2. Experimental studies are needed to determine further the underlying mechanisms responsible for these associations.

Third-party tolerogenic dendritic cells reduce allo-reactivity in vitro and ameliorate the severity of acute graft-versus-host disease in allo-bone marrow transplantation

Tolerogenic dendritic cells (tDCs) potently induce and maintain tolerance based on their distinct characteristics compared with conventional DCs. Recent reports show that donor or host tDCs promote allograft survival in mice. In this study, the efficacy of third-party tDCs in the prevention of acute graft-versus-host disease (aGVHD) was evaluated. In vitro, tDCs derived from the bone marrow (BM) of D1 mice were induced by GM-CSF, IL-10 and TGF-β1. The phenotypes, expression of cytokines and suppression of tDCs were analysed. In vivo, the effects of adoptive transfer of third-party-tDCs were evaluated in an MHC-mismatched aGVHD mouse model. Survival, body weight, GVHD scoring, histopathological specimens and serum cytokines were analysed in tDC-treated mice and untreated controls. Tolerogenic DCs had low expression of MHC and co-stimulatory molecules, expressed high levels of 'immunosuppressive' cytokines and suppressed allo-CD4(+) T cell proliferation. In the B6→D2 mouse model, all aGVHD mice died within 18 days. Fortunately, third-party tDCs transferred at low doses (10(4)) effectively prolonged survival after allo-BMT. Furthermore, in the mice treated with 10(4) tDCs, serum levels of IL-10/TGF-β were significantly higher and the percentage of Foxp3(+) cells continually increased compared with the mice treated with other doses of tDCs. Third-party tDCs play a crucial role in reducing the severity of aGVHD by modulating the secretion of various cytokines and expanding Foxp3(+) regulatory T cells, which suggests the possibility of using third-party tDCs for therapeutic applications. Furthermore, special attention should be paid to the optimal range of tDCs for preventing allograft rejection.

Embryonic morphogen nodal is associated with progression and poor prognosis of hepatocellular carcinoma

Background

Nodal, a TGF-β-related embryonic morphogen, is involved in multiple biologic processes. However, the expression of Nodal in hepatocellular carcinoma (HCC) and its correlation with tumor angiogenesis, epithelial-mesenchymal transition, and prognosis is unclear.

Methods

We used real-time PCR and Western blotting to investigate Nodal expression in 6 HCC cell lines and 1 normal liver cell line, 16 pairs of tumor and corresponding paracarcinomatous tissues from HCC patients. Immunohistochemistry was performed to examine Nodal expression in HCC and corresponding paracarcinomatous tissues from 96 patients. CD34 and Vimentin were only examined in HCC tissues of patients mentioned above. Nodal gene was silenced by shRNA in MHCC97H and HCCLM3 cell lines, and cell migration and invasion were detected. Statistical analyses were applied to evaluate the prognostic value and associations of Nodal expression with clinical parameters.

Results

Nodal expression was detected in HCC cell lines with high metastatic potential alone. Nodal expression is up-regulated in HCC tissues compared with paracarcinomatous and normal liver tissues. Nodal protein was expressed in 70 of the 96 (72.9%) HCC tumors, and was associated with vascular invasion (P = 0.000), status of metastasis (P = 0.004), AFP (P = 0.049), ICGR₁₅ (indocyanine green retention rate at 15 min) (P = 0.010) and tumor size (P = 0.000). High Nodal expression was positively correlated with high MVD (microvessal density) (P = 0.006), but not with Vimentin expression (P = 0.053). Significantly fewer migrated and invaded cells were seen in shRNA group compared with blank group and negative control group (P<0.05). High Nodal expression was found to be an independent factor for predicting overall survival of HCC.

Conclusions

Our study demonstrated that Nodal expression is associated with aggressive characteristics of HCC. Its aberrant expression may be a predictive factor of unfavorable prognosis for HCC after surgery.

The association between the C677T polymorphism in MTHFR gene and the risk of thyroid cancer: a meta-analysis

OBJECTIVES

Methylenetetrahydrofolate reductase (MTHFR) enzyme plays an important role in folate metabolism and MTHFR C677T polymorphism has been suggested as a risk factor to various cancers. It is a common genetic alteration and may affect the host susceptibility to thyroid cancer. The aim of this study was to investigate the association between MTHFR C677T polymorphism and thyroid cancer risk by performing a meta-analysis.

MATERIALS AND METHODS

PubMed, EMbase, CNKI and Wanfang databases were searched for case-control studies investigating the association between MTHFR C677T polymorphism and thyroid cancer risk. OR with 95%CI was used to assess this possible association. Four individual case-control studies with a total of 360 cases and 900 controls were included into this meta-analysis.

RESULTS

Meta-analyses showed there was significant association between MTHFR C677T polymorphism and thyroid cancer risk: TT vs. CC: OR = 2.06, 95% CI = 1.04-4.10, p = 0.04; T vs. C: OR = 2.06, 95% CI = 1.97-3.77, p = 0.04.

CONCLUSIONS

This meta-analysis supports an association between MTHFR C677T polymorphism and thyroid cancer risk. Further studies with large sample size and careful design are needed to identify this association more comprehensively.

Coding completeness and quality of relative survival-related variables in the National Program of Cancer Registries Cancer Surveillance System, 1995-2008

BACKGROUND

Calculating accurate estimates of cancer survival is important for various analyses of cancer patient care and prognosis. Current US survival rates are estimated based on data from the National Cancer Institute's (NCI's) Surveillance, Epidemiology, and End RESULTS (SEER) program, covering approximately 28 percent of the US population. The National Program of Cancer Registries (NPCR) covers about 96 percent of the US population. Using a population-based database with greater US population coverage to calculate survival rates at the national, state, and regional levels can further enhance the effective monitoring of cancer patient care and prognosis in the United States. The first step is to establish the coding completeness and coding quality of the NPCR data needed for calculating survival rates and conducting related validation analyses.

METHODS

Using data from the NPCR-Cancer Surveillance System (CSS) from 1995 through 2008, we assessed coding completeness and quality on 26 data elements that are needed to calculate cancer relative survival estimates and conduct related analyses. Data elements evaluated consisted of demographic, follow-up, prognostic, and cancer identification variables. Analyses were performed showing trends of these variables by diagnostic year, state of residence at diagnosis, and cancer site.

RESULTS

Mean overall percent coding completeness by each NPCR central cancer registry averaged across all data elements and diagnosis years ranged from 92.3 percent to 100 percent. RESULTS showing the mean percent coding completeness for the relative survival-related variables in NPCR data are presented. All data elements but 1 have a mean coding completeness greater than 90 percent as was the mean completeness by data item group type. Statistically significant differences in coding completeness were found in the ICD revision number, cause of death, vital status, and date of last contact variables when comparing diagnosis years. The majority of data items had a coding quality greater than 90 percent, with exceptions found in cause of death, follow-up source, and the SEER Summary Stage 1977, and SEER Summary Stage 2000.

CONCLUSION

Percent coding completeness and quality are very high for variables in the NPCR-CSS that are covariates to calculating relative survival. NPCR provides the opportunity to calculate relative survival that may be more generalizable to the US population.

Association between body fat distribution and androgen deficiency in middle-aged and elderly men in China

The objective of the present study was to examine the association between body fat distribution and total testosterone (TT) and free testosterone (FT) levels among middle-aged and elderly men. A total of 922 male residents aged 40-70 years from a community in Shanghai, China, participated in the study. Their waist circumference (WC), waist-height ratio (WHtR), body mass index (BMI), and TT and FT concentrations were measured. Logistic regression models were used to estimate testosterone deficiency risk on the basis of anthropometric indices. BMI, WC and WHtR were all associated with TT deficiency. The participants in the highest quartiles of above-mentioned anthropometric indices had the highest risk of TT deficiency (BMI: odds ratio (OR)=4.40, 95% confidence interval (CI)=2.69-7.19; WC: OR=3.47, 95% CI=2.14-5.60; WHtR: OR=2.89, 95% CI=1.76-4.76). WC and WHtR were associated with FT deficiency. The participants in the highest quartiles had the highest risk of FT deficiency (WC: OR=1.87, 95% CI=1.18-2.97; WHtR: OR=1.67, 95% CI=1.04-2.66). The association between BMI and FT deficiency was not statistically significant (OR=1.21 for the highest quartile, 95% CI=0.78-1.87). Our study demonstrated that both general and abdominal obesity were associated with TT deficiency, whereas only abdominal obesity was found to be associated with FT deficiency.

[Comparison of gonadotropin releasing hormone agonist long protocol and gonadotropin releasing hormone antagonist protocol in infertile women]

OBJECTIVE

To compare the clinical outcomes of GnRH agonist (GnRH-a) long protocol and GnRH antagonist (GnRH-ant)protocol in vitro fertilization (IVF)-embryo transfer (ET) cycles, and to explore the optimized protocol for infertile women.

METHODS

From June 2010 to June 2012, 2 444 infertile women underwent their IVF cycles in Peking University Third Hospital, which were divided into 1 706 GnRH agonist long protocol and 738 GnRH antagnist protocol groups. The data of the general demographic, treatment and clinical outcome were compared between the two groups.

RESULTS

The age, body mass index(BMI), infertile duration, antral follicle count (AFC) did not reach statistical difference, the level of estradiol on the day of HCG: injection was higher in GnRH agonist group [(10 595±7 368)pmol/L vs. (9 087±7 035) pmol/L], and the mean length of stimulation was longer in GnRH agonist group[(12.5±1.8) d vs.(9.4±1.7) d], The dose of Gn [(3 107±1 377) IU vs. (2 084±903)IU]was higher in GnRH agonist group. The number of ovum was 13.4±6.6 in GnRH agonist group and 11.8±6.4 in GnRH antagonist group. Those clinical parameters all reached statistical difference (P<0.05). The number of the transfer embryos, fertilization rate, and cleavage rate did not reach statistical difference, but the number of the embryos was 5.6±4.5 in GnRH agonist group and 5.1±4.3 in GnRH antagonist group,reached statistical difference (P<0.05). The abortion rate, embryonic death rate, ectopic pregnancy rate, preterm labor rate, postterm pregnancy rate, fatal malformations rate showed no statistical difference, but the GnRH agonist long protocol had higher pregnancy rate (44.0% vs. 38.3%), and higher term pregnancy rate (64.2% vs. 56.9%) compared with GnRH antagonist protocol, thus those parameter reached significant difference (P<0.05).

CONCLUSION

Compared with GnRH-antagnist protocol, GnRH agonist long protocol had higher pregnancy rate and better pregnancy outcome.

Attenuation of γ-aminobutyric acid (GABA) transaminase activity contributes to GABA increase in the cerebral cortex of mice exposed to β-cypermethrin

The current study investigated the γ-aminobutyric acid (GABA) levels and GABA metabolic enzymes (GABA transaminase (GABAT) and glutamate decarboxylase (GAD)) activities at 2 and 4 h after treatment, using a high-performance liquid chromatography with ultraviolet detectors and colorimetric assay, in the cerebral cortex of mice treated with 20, 40 or 80 mg/kg β-cypermethrin by a single oral gavage, with corn oil as vehicle control. In addition, GABA protein (4 h after treatment), GABAT protein (2 h after treatment) and GABA receptors messenger RNA (mRNA) expression were detected by immunohistochemistry, Western blot and real-time quantitative reverse transcriptase polymerase chain reaction, respectively. β-Cypermethrin (80 mg/kg) significantly increased GABA levels in the cerebral cortex of mice, at both 2 and 4 h after treatment, compared with the control. Also, GABA immunohistochemistry results suggested that the number of positive granules was increased in the cerebral cortex of mice 4 h after exposure to 80 mg/kg β-cypermethrin when compared with the control. Furthermore, the results also showed that GABAT activity detected was significantly decreased in the cerebral cortex of mice 2 h after β-cypermethrin administration (40 or 80 mg/kg). No significant changes were found in GAD activity, or the expression of GABAT protein and GABAB receptors mRNA, in the cerebral cortex of mice, except that 80 mg/kg β-cypermethrin caused a significant decrease, compared with the vehicle control, in GABAA receptors mRNA expression 4 h after administration. These results suggested that attenuated GABAT activity induced by β-cypermethrin contributed to increased GABA levels in the mouse brain. The downregulated GABAA receptors mRNA expression is most likely a downstream event.

Computational peptidology: a new and promising approach to therapeutic peptide design

The recent focus on protein-protein interaction networks has increasingly been shifted towards the disruption of protein complexes, which either are mediated by the binding of a globular domain in one protein to a short peptide stretch in another, or involve flat, large, and hydrophobic interfaces that classical small-molecule agents are not always ideally suited. Rational design of therapeutic peptides with high affinity targeting such interactions has emerged as a new and promising tool in discovery of potential drug candidates against associated diseases. The design is commonly based on bioinformatics methods or molecular modeling techniques, indirectly exploiting structure-activity relationship at the level of peptide sequence or directly deriving lead entities from protein complex architecture. Here, a newly rising subfield called computational peptidology that focuses on the use of computational and theoretical approaches to treat peptide-related problems is comprehensively reviewed on the design and discovery of peptide agents targeting protein-protein interactions. We address a systematic discussion on several representative cases in which the computational peptidology is successfully employed to develop peptide therapeutics. Besides, some problems and pitfalls accompanied with the current use of computational methods in peptide modeling and design are also present.