Urinary mRNA expression of ACE and ACE2 in human type 2 diabetic nephropathy

AIMS/HYPOTHESIS

The interplay of ACE and type 2 ACE (ACE2) has been recognised as playing an important role in the tissue renin-angiotensin system within the kidney. In the present study, we measured urinary mRNA expression of ACE and ACE2 in patients with type 2 diabetic nephropathy.

METHODS

We studied 50 patients with diabetic nephropathy: 26 were being treated by ACE inhibitor (ACEI) alone (ACEI group), the other 24 by ACEI and angiotensin-receptor blocker (ARB) (ACEI+ARB group). mRNA expression of ACE and ACE2 was measured by real-time quantitative RT-PCR at 0 and 12 weeks. All patients were then followed for 56 weeks.

RESULTS

Proteinuria correlated significantly with urinary ACE (r=0.454, p=0.001) and ACE2 expression (r=0.651, p<0.001). Urinary ACE2 expression correlated with estimated GFR (r= -0.289, p=0.042). In the ACEI group, there was a significant inverse correlation between the rate of GFR decline and urinary ACE2 expression at baseline (r= -0.423, p=0.031) as well as at 12 weeks (r= -0.395, p=0.046). In contrast, there was no significant correlation between the rate of GFR decline and urinary ACE2 expression at baseline or at 12 weeks in the ACEI+ARB group. The rate of GFR decline did not correlate with the baseline urinary ACE expression of either group.

CONCLUSION/INTERPRETATION

There was a relationship between urinary mRNA expression of ACE2 and the degree of proteinuria. The physiological implication and possibility of clinical application of quantifying urinary ACE2 expression require further study.

Overexpression of cyclooxygenase-2 is associated with chemoradiotherapy resistance and prognosis in esophageal squamous cell carcinoma patients

Our objective was to investigate whether cyclooxygenase-2 (COX-2) expression can predict the patient's response to chemoradiotherapy (CRT) and ensuing prognosis in esophageal squamous cell carcinoma (ESCC). The clinicopathological and follow-up data of 112 patients with ESCC who underwent CRT from January 2001 to June 2006 were analyzed retrospectively. The immunohistochemical expression level of COX-2 was examined for all biopsy specimens of primary tumors, and the correlation of COX-2 expression with the patient's response to CRT and prognosis was examined. COX-2 positive immunostaining was detected in 111 (99.1%) of the patients, including overexpression in 54 (48.2%) patients and low expression in 58 (51.8%) of the patients. The response of tumors with a low level expression of COX-2 (70.7%, 41/58) was significantly higher than that of tumors with COX-2 overexpression (42.6%, 23/54; P = 0.003). Patients with a low level of COX-2 expression had a higher downstaged rate than those with a high level of COX-2 expression (9/13 vs 2/8), but the difference was not statistically significant (P = 0.08). In the definitive CRT group (91 cases), COX-2 overexpression was significantly associated with poor 3-year overall survival (P = 0.028). Multivariate analysis showed that only metastatic stage (nonregional node metastasis) was an independent prognosis factor. The assessment of COX-2 status may provide additional information to identify ESCC patients with poor chances of response to CRT and potential candidates for more individualized treatment.

Increased amyloid beta-peptide (1-40) level in brain of streptozotocin-induced diabetic rats

The aims of the study were to investigate whether the level of amyloid beta-peptide (Abeta) (1-40) was increased in brain of diabetic rats and whether the increase was associated with dysfunction of P-glycoprotein at the blood-brain barrier. A diabetes-like condition was induced by single administration of 65 mg/kg streptozotocin via i.p. injection. Abeta (1-40) levels in brain of the diabetic rats were measured using an enzyme linked immunosorbent assay (ELISA) kit. The in vivo brain-to-blood efflux and blood-to-brain influx transport of [(125)I]-labeled human amyloid-beta-peptide (hAbeta) (1-40) were measured using the brain efflux index and brain permeability coefficient-surface area product, respectively. [(14)C]inulin served as a reference compound. The results showed that Abeta (1-40) levels significantly increased in temporal cortex and hippocampus of the diabetic rats. The brain remaining percentage of [(125)I]hAbeta (1-40) in diabetic rats significantly increased at 30 min after intracerebral microinjection, accompanied by decrease of the brain efflux index. Pretreatment of P-glycoprotein inhibitors verapamil or cyclosporin A significantly increased the brain remaining percentage of [(125)I]hAbeta (1-40). The brain permeability coefficient-surface area product of [(125)I]hAbeta (1-40) was increased in diabetic rats, accompanied by increased Abeta (1-40) levels in plasma. The present study demonstrated that a diabetic state could increase Abeta (1-40) levels in brain, which might be explained, at least in part, by the decline in brain-to-blood efflux of Abeta (1-40) due to deficient cerebral P-glycoprotein function in diabetic rats.

New organic FET-like photoactive device, experiments and DFT modeling

We present the possible construction of an organic FET-like photoactive device in which source-drain current through a phthalocyanine ( H(2)Pc film is affected by a photo-induced dipolar field in a photoactive "gate" electrode. The influence of the dipolar electric field on charge transfer between H(2)Pc molecules is modeled by DFT quantum-chemical calculations on H(2)Pc dimers and tetramers.

TMLNN: triple-valued or multiple-valued logic neural network

We discuss the problem of representing and processing triple-valued or multiple-valued logic knowledge using neural network in this paper. A novel neuron model, triple-valued or multiple-valued logic neuron (TMLN), is presented. Each triple-valued or multiple-valued logic neuron can represent a triple-valued or multiple-valued logic rule by itself. We will show that there are two triple-valued or multiple-valued logic neurons: TMLN-AND (triple-valued or multiple-valued "logic and" neuron) and TMLN-OR (triple-valued or multiple-valued "logic or" neuron). TMLN-AND can realize triple-valued or multiple-valued "logic and" while TMLN-OR can realize triple-valued or multiple-valued "logic or." Two simplified triple-valued or multiple-valued logic neuron models are also presented. We can show that a multiple-layer neural network (TMLNN) made up of triple-valued or multiple-valued logic neurons can implement a triple-valued or multiple-valued logic inference system. The training algorithm for TMLNN is presented and can be shown to converge. In our model, triple-valued or multiple-valued logic rules can be extracted from TMLNN with ease. TMLNN can thus form a base for representing logic knowledge using neural network.

Gene-gene interaction between FGF20 and MAOB in Parkinson disease

The fibroblast growth factor 20 (FGF20) and monoamine oxidase B (MAOB) genes are associated with Parkinson Disease (PD) risk and both are in the dopamine bio-pathway. Therefore, we investigated the joint effect between polymorphisms in the FGF20 and MAOB genes for evidence of interaction contributing to PD risk. Fourteen polymorphisms (eight for FGF20, six for MAOB) were genotyped in 736 families and analyzed using conditional logistic regression (CLR). Significant two-locus interactions were found in females between the polymorphisms rs1721100 of FGF20 and rs1799836 of MAOB, and between the polymorphisms rs1721082 of FGF20 and rs1799836 of MAOB. The risk alleles for each SNP identified from CLR, rs1721100 C, rs1721082 T and rs1799836 A, are consistent with previous reports. Using indicator variables for the SNP genotypes, rs1721100 GC with rs1799836 AA showed significant interaction (P = 0.021), compared with the reference group rs1721100 GG with rs1799836 GG. Using an allele-dose model for the risk alleles, rs1721100 and rs1799836 showed significant interaction (P = 0.019). We found similar interaction results between rs1721082 and rs1799836. In conclusion, variants in FGF20 and MAOB show evidence of statistical interactions, which emphasizes the importance of considering them jointly in genetic analysis of PD and illustrates potential patterns of biological interaction contributing to PD risk.

Soil nitrogen dynamics in irrigated maize systems as impacted on by nitrogen and stubble management

The soil nitrogen (N) dynamics of an irrigated maize system in which stubble retention and stubble burned treatments were superimposed over treatments of varying N fertiliser rate were studied. The field site was near Whitton, New South Wales, Australia, and the work described here is part a life cycle analysis of greenhouse gas emissions from maize project. The objective of this part of the work was to quantify the fate of fertiliser N applied at the site. Field measurements of denitrification, mineral N content and recovery of 15N-labelled urea from microplots with and without ammonium thiosulfate were complimented with laboratory studies of denitrification and nitrous oxide (N2O) flux. Significantly (P < 0.05) more fertiliser N was recovered in the grain from the stubble incorporated treatment than the stubble burned treatment and there was greater recovery of fertiliser N in the soil at the end of the experiment in the stubble burned treatment. This may indicate that fertiliser N applied to the stubble burned system may be more exposed to soil-N transformations. The reason for the difference in uptake and soil residual is not clear but may be related to soil structure differences leading to less plant accessibility of N in the burned treatment. This difference may lead to more nitrous oxide emission from soil in the stubble burned treatments. Short-term (1 h) static chamber measurements in the field found a strong N-rate dependence of N2O emission rate for fertiliser rates between 0 and 300 kg N/ha. Inclusion of ammonium thiosulfate in the fertiliser formulation did not appear to have a significant impact on fertiliser N recovery.

Energy balance and cost-benefit analysis of biogas production from perennial energy crops pretreated by wet oxidation

Perennial crops need far less energy to plant, require less fertilizer and pesticides, and show a lower negative environmental impact compared with annual crops like for example corn. This makes the cultivation of perennial crops as energy crops more sustainable than the use of annual crops. The conversion into biogas in anaerobic digestion plants shows however much lower specific methane yields for the raw perennial crops like miscanthus and willow due to their lignocellulosic structure. Without pretreatment the net energy gain is therefore lower for the perennials than for corn. When applying wet oxidation to the perennial crops, however, the specific methane yield increases significantly and the ratio of energy output to input and of costs to benefit for the whole chain of biomass supply and conversion into biogas becomes higher than for corn. This will make the use of perennial crops as energy crops competitive to the use of corn and this combination will make the production of biogas from energy crops more sustainable.

Monoclonal antibodies against the nucleocapsid proteins of henipaviruses: production, epitope mapping and application in immunohistochemistry

Four monoclonal antibodies (mAbs) were generated by immunizing BALB/C mice with recombinant nucleocapsid protein (N) of Nipah virus (NiV) and Hendra virus (HeV) expressed in E. coli. Two mAbs each were obtained for the HeV N and NiV N, respectively. All four mAbs displayed specific reactivity with the recombinant N proteins of both viruses by western blot, which was further confirmed by immunofluorescent antibody assay using fixed insect cells infected with recombinant baculoviruses expressing either the HeV or NiV N protein. Epitope mapping using a 12-mer random peptide phage display library revealed two linear antigenic sites of the henipavirus N proteins, KLxR (aa 17-20) and FKREM (aa 446-450), which have not been reported previously. Two of the mAbs were able to specifically recognize HeV antigens by immunohistochemical staining of lung tissue sections of a horse experimentally infected with HeV. These reagents will be a useful addition to the collection of tools essential for further research and improvement in diagnosis of henipaviruses.

Modeling photon propagation in biological tissues using a generalized Delta-Eddington phase function

Photon propagation in biological tissue is commonly described by the radiative transfer equation, while the phase function in the equation represents the scattering characteristics of the medium and has significant influence on the precision of solution and the efficiency of computation. In this work, we present a generalized Delta-Eddington phase function to simplify the radiative transfer equation to an integral equation with respect to photon fluence rate. Comparing to the popular diffusion approximation model, the solution of the integral equation is highly accurate to model photon propagation in the biological tissue over a broad range of optical parameters. This methodology is validated by Monte Carlo simulation.

Measurement of transverse single-spin asymmetries for Dijet production in proton-proton collisions at sqrt[s]=200 GeV

We report the first measurement of the opening angle distribution between pairs of jets produced in high-energy collisions of transversely polarized protons. The measurement probes (Sivers) correlations between the transverse spin orientation of a proton and the transverse momentum directions of its partons. With both beams polarized, the wide pseudorapidity (-1< or = eta < or = +2) coverage for jets permits separation of Sivers functions for the valence and sea regions. The resulting asymmetries are all consistent with zero and considerably smaller than Sivers effects observed in semi-inclusive deep inelastic scattering. We discuss theoretical attempts to reconcile the new results with the sizable transverse spin effects seen in semi-inclusive deep inelastic scattering and forward hadron production in pp collisions.

Flux vector formulation for photon propagation in the biological tissue

We present a generalized delta-Eddington phase function to simplify the radiative transfer equation to an integral equation with respect to the photon flux vector. The solution of the integral equation is highly accurate to model the photon propagation in the biological tissue over a broad range of optical parameters, especially in the visible light spectrum where the diffusion approximation breaks down. The methodology is validated in the Monte Carlo simulation and can be applied in various optical imaging applications.

Repeated epicutaneous exposures to ovalbumin progressively induce atopic dermatitis-like skin lesions in mice

BACKGROUND

Atopic dermatitis (AD) is a chronic skin disease in which environmental factors play a great role. A widely used murine model for AD has provided a useful tool to study the disease.

OBJECTIVE

The purpose of this study is to investigate kinetically the induction of this AD model and the processes involved in the development of AD due to extrinsic allergen exposures.

METHODS

BALB/c mice were epicutaneously exposed to ovalbumin (OVA) for 3 weeks; each week was separated by a 2-week resting period. Mice were killed after each exposure week. Skin biopsies and blood were obtained for histological study, RNA isolation and antibody analysis.

RESULTS

There was a progressive and significant thickening of the epidermis and dermis in OVA-exposed mice. Significantly increased dermal cell infiltration of eosinophils, mast cells and total inflammatory cells, including CD3 and CD4 cells, was found after each OVA exposure week. Total IgE, IgG2a and OVA-specific IgE were significantly increased after the second and third exposure week, while OVA-specific IgG2a was significantly induced after the third exposure week. Gradual and/or significant increases in mRNA expression of IL-1beta, TNF-alpha, IL-4, IL-10, IL-13, IFN-gamma and IL-12p35 were found after each exposure week. Chemokines and their receptors involved in both T-helper type 1 (Th1)- and Th2-type cell recruitment (CCL1, CCL8, CCL11, CCL24, CXCL9, CXCL10, CCR1, CCR3, CCR5, CCR8 and CXCR3) were up-regulated significantly at different time-points.

CONCLUSION

This study provides an insight into the dynamic nature and time-dependent transition of skin inflammation and systemic immune responses in a murine AD model induced by repeated epicutaneous exposures to OVA.

Knowledge and willingness toward living organ donation: a survey of three universities in Changsha, Hunan Province, China

BACKGROUND

This study was conducted to clarify the knowledge and attitudes of Chinese university students regarding living organ donation and analyze the determinants impacting their decisions.

METHODS

A questionnaire was delivered to college students chosen by random assignment. The data was analyzed by Statistics Package for Social Science (SPSS) software.

RESULTS

Of 434 participants, 49.8% indicated they would be willing to be living organ donors, 58.4% believed living organ donation could ease the organ shortage, 48.2% thought that the recovery rate of recipients of living organ donors transplants was equal to or even better than deceased donation, 62.4% designated relatives as their most probable recipients, 48.0% argued that partial compensation was an effective method to increase live organ donation, and 53.7% wished to donate through transplantation centers. According to univariate analysis, attitudes regarding the value of life, relationship between body integrity and health as well as body integrity and conventional culture were factors that impacted on an individual's decision. Students' knowledge of the value of living organ transplantation and their economic background were considered to be determinants of individual willingness. Furthermore, the operation's impact on quality of life and postoperative complications were additional concerns. Multivariate analysis indicated that other factors influencing students' willingness to donate included attitudes toward the relationship between body integrity and health, beliefs regarding body integrity and conventional culture, value of living donor organ transplantation, economic background of students, and anxiety about the impact on postoperative complications.

CONCLUSIONS

Numerous students were willing to participate in living organ donation. At the same time, social education and advertisements for living organ donation were far from adequate, having little or no influence on the decision-making process.

Partonic Flow and phi-Meson production in Au+Au collisions at sqrt radical sNN = 200 GeV

We present first measurements of the phi-meson elliptic flow (v2(pT)) and high-statistics pT distributions for different centralities from radical sNN=200 GeV Au+Au collisions at RHIC. In minimum bias collisions the v2 of the phi meson is consistent with the trend observed for mesons. The ratio of the yields of the Omega to those of the phi as a function of transverse momentum is consistent with a model based on the recombination of thermal s quarks up to pT approximately 4 GeV/c, but disagrees at higher momenta. The nuclear modification factor (R CP) of phi follows the trend observed in the K S 0 mesons rather than in Lambda baryons, supporting baryon-meson scaling. These data are consistent with phi mesons in central Au+Au collisions being created via coalescence of thermalized s quarks and the formation of a hot and dense matter with partonic collectivity at RHIC.

Nanoscale periodic morphologies on the fracture surface of brittle metallic glasses

Out-of-plane, nanoscale periodic corrugations are observed in the dynamic fracture surface of brittle bulk metallic glasses with fracture toughness approaching that of silica glasses. A model based on the meniscus instability and plastic zone theory is used to explain such dynamic crack instability. The results indicate that the local softening mechanism in the fracture is an essential ingredient for controlling the formation of the unique corrugations, and might provide a new insight into the origin of fracture surface roughening in brittle materials.