Mechanical Properties of Cu2O Thin Films by Nanoindentation.

In this study, the structural and nanomechanical properties of Cu2O thin films are investigated by X-ray diffraction (XRD), atomic force microscopy (AFM), scanning electron microscopy (SEM) and nanoindentation techniques. The Cu2O thin films are deposited on the glass substrates with the various growth temperatures of 150, 250 and 350 °C by using radio frequency magnetron sputtering. The XRD results show that Cu2O thin films are predominant (111)-oriented, indicating a well ordered microstructure. In addition, the hardness and Young's modulus of Cu2O thin films are measured by using a Berkovich nanoindenter operated with the continuous contact stiffness measurements (CSM) option. Results indicated that the hardness and Young's modulus of Cu2O thin films decreased as the growth temperature increased from 150 to 350 °C. Furthermore, the relationship between the hardness and films grain size appears to closely follow the Hall-Petch equation.

Functional profiling of the Tritrichomonas foetus transcriptome and proteome.

Tritrichomonas foetus is a potent veterinary pathogen, causing bovine and feline trichomoniasis. The principal clinical manifestation of infection in cattle is inflammation of the genital tract and infertility. In feline, the parasite causes large-bowel disease resulting in chronic diarrhea. In contrast to other well-studied protozoan, genetic data regarding the molecular characterization and expression in T. foetus is far less understood. In this study, the first large-scale T. foetus expressed sequence tag (TfEST) project was conducted on 5064 randomly selected EST clones from a non-normalized unidirectional Tf30924 cDNA library. Assembling of 5064 single-pass sequences from the 5' end resulted in 713 contigs and 1961 singlets. BLAST search revealed that 53.52% of the unigenes showed significant similarity to known sequences or protein motifs/domains. Functional classifications indicated that most of the unigenes are involved in translation, ribosomal structure and ribosome biogenesis. The average GC content of the T. foetus transcriptome is 40.93%. Intriguingly, only 31.29% of the unigenes contain the classical AAUAAA polyadenylation signal sequence at the 3'-UTR region. Furthermore, a panel of potential chemotherapeutic targets was also identified for the first time in T. foetus. The protein expression levels were verified by using two-dimensional electrophoresis and matrix-assisted laser desorption ionization time-of-flight mass spectrometry. A total of 68 highly abundant protein spots were successfully identified in the reference 2-DE map based on our T. foetus-specific protein database. The EST dataset and the reference 2-DE map established in the present study will provide a foundation for future whole genome sequencing project and comparative transcriptomic/proteomic analyses to provide potential drug targets against T. foetus infection.

Long-term use of fenofibrate is associated with increased prevalence of gallstone disease among patients undergoing maintenance hemodialysis.

BACKGROUND: In spite of insufficient evidence to guide the use of lipid-lowering drugs (LLDs) among the dialysis population, these drugs are frequently used to treat dyslipidemia. Several studies have found that long-term use of LLDs is associated with an increased risk of gallstone disease (GSD) in the general population. However, the lithogenic risk of LLDs in patients undergoing hemodialysis (HD) has not been studied. AIM: It is to assess the influence of long-term use of LLDs on the prevalence of GSD among patients undergoing HD. METHODS: This cross-sectional study included 108 eligible patients receiving maintenance HD: 35 receiving lovastatin; 34 fenofibrate; and 39 no LLD. GSD was defined as the presence of gallstones or the performance of cholecystectomy while taking LLD. Abdominal ultrasonography, demographic parameters, and laboratory data were obtained for all enrolled subjects. ANOVA with Bonferroni's test and chi-square test were used to compare differences among the three groups. RESULTS: The three groups had similar clinical characteristics with regard to age, gender, duration of HD, body mass index, and total cholesterol values. However, a significantly higher prevalence of GSD and higher triglyceride levels were found in patients receiving fenofibrate, compared with those in other groups (p < 0.05). Among dialysis patients on fenofibrate, increased age, female gender, larger daily dose, and longer duration of treatment were associated with increased risks for GSD. CONCLUSIONS: Our study shows that long-term use of fenofibrate is related to increased risk of GSD among HD patients. Further large-scale studies are needed to confirm our findings.

Nutritional status of vegetarians on maintenance haemodialysis.

AIM: Vegetarian diets have long been thought of as beneficial to health. However, vegetarian diets are often low in protein, which is contradictory to the high protein diet guideline for uraemia patients. The purpose of the study was to investigate the impact of a vegetarian diet on the nutritional status of haemodialysis (HD) patients. METHODS: Patients on chronic HD for over 6 months were included in the study. The normalized protein catabolic rate (nPCR) was used to reflect daily protein intake. Biochemical markers of nutrition, anthropometric parameters, subjective global assessment (SGA) and functional activity of daily living were assessed to evaluate the nutritional status of vegetarians on chronic HD. RESULTS: Nineteen out of 318 HD patients were vegetarians. The nPCR was lower in the vegetarian group (1.20 ± 0.24 vs 1.10 ± 0.29 g/kg per day, non-Veg vs Veg, P < 0.05). The serum albumin and prealbumin were similar in vegetarian and non-vegetarian HD patients. The body mass index (BMI) and mid-arm muscular circumference (MAMC) were lower in vegetarian patients (P < 0.05). The haematocrit of vegetarians can be maintained at a level similar to that of non-vegetarian patients but erythropoietin doses needed were higher in vegetarian patients (P < 0.05). The muscle strength evaluated by the hand-grip test, SGA and activities of daily living were similar in vegetarians and non-vegetarians. CONCLUSION: The present study revealed that HD patients on vegetarian diets might have a smaller BMI, but SGA and function of daily activities were similar to those of the non-vegetarians. The haematocrit of vegetarians can be maintained with a higher erythropoietin dose.

Prophylactic use of omeprazole associated with a reduced risk of peptic ulcer disease among maintenance hemodialysis patients.

BACKGROUND: Patients undergoing maintenance hemodialysis (MHD) have a high prevalence of peptic ulcer disease (PUD). Omeprazole is a proton pump inhibitor with proven efficacy in the prevention and treatment of PUD. However, there is little data on the prophylactic use of omeprazole in reducing the risk of PUD among MHD patients. METHODS: This prospective study included 93 patients undergoing MHD at Zen-Ho Dialysis Center between July 2008 and December 2009. Fifty-three patients were assigned to receive 20 mg of omeprazole daily for 18 months and 40 patients served as control. The Kaplan-Meier method was applied to calculate the cumulative incidence of PUD. RESULTS: The per-protocol population comprised 85 patients (omeprazole group, 49; control group, 36). Both groups had similar baseline characteristics. The need for endoscopy was found to be significantly less (10.2 vs. 44.4%, p = 0.001) in the omeprazole group than in the control group. Dialysis patients in the omeprazole group required fewer blood transfusions and erythropoietin doses than did the control group patients. Kaplan-Meier analysis revealed a higher cumulative ulcer rate in the control group (log-rank test, p = 0.04). However, omeprazole did not reduce the risk of PUD in MHD patients on regular aspirin or warfarin. CONCLUSIONS: We conclude that prophylactic use of omeprazole might be effective to lower the incidence of PUD among MHD patients without regular aspirin or warfarin use. Further large-scale controlled trials should be carried out to confirm our findings.

A proteome reference map of Trichomonas vaginalis.

Trichomoniasis caused by Trichomonas vaginalis is the most common sexual transmitted infection in the world. The 170-MB genome of this protozoan contains 60,000 genes, the largest number of genes ever identified in protozoan. High-throughput expression sequenced tag analysis showed that at least 4,000 genes were expressed in the trophozoite stage. In the present study, we use two-dimensional electrophoresis combined with matrix-assisted laser desorption ionization time-of-flight mass spectrometry analysis to profile, identify, and characterize proteins expressed in the trophozoite stage of T. vaginalis. A total of 247 spots representing 164 different proteins were identified. The identified proteins with known sequence or motif/domain homologies were further classified into groups according to their biological functions. Among them, proteins related to carbohydrate metabolism represented the most abundant category in the T. vaginalis proteome. This study presented the most extensive proteomic analysis of T. vaginalis to date and provided a reference proteome database for future comparative proteomic studies.

8-iso-prostaglandin F2alpha as a useful clinical biomarker of oxidative stress in ESRD patients.

BACKGROUND/AIMS: Chronic renal failure is associated with elevated indices of oxidative stress. We tested the hypothesis that the in vivo formation of the F(2)-isoprostane (8-iso-prostaglandin PGF(2alpha)), a bioactive product of arachidonic acid peroxidation, is enhanced in end-stage renal disease (ESRD) patients receiving hemodialysis (HD) and continuous ambulatory peritoneal dialysis (CAPD). METHODS: Plasma samples were obtained from 35 HD patients, 30 CAPD patients and 30 age- and sex-matched healthy subjects for measurement of immunoreactive 8-iso-PGF(2alpha). RESULTS: Plasma 8-iso-PGF(2alpha) levels were significantly higher (p < 0.001) in HD and CAPD patients (346.3 +/- 132.4 pg/ml; range 49.8-870) than in age-matched control subjects (150.9 +/- 61.6 pg/ml; range 33.5-235). In addition, we also found that 8-iso-PGF(2alpha) concentration was significantly (p = 0.007) higher in HD patients (389.8 +/- 148.3 pg/ml) than in CAPD patients (254.3 +/- 76.6 pg/ml). Plasma 8-iso-PGF(2alpha) concentration was linearly correlated with serum haptoglobin, C-reactive protein (CRP) and plasma MDA (r = 0.58, p = 0.003; r = 0.29, p < 0.05 and r = 0.38, p < 0.05 respectively). On the other hand, plasma 8-iso-PGF(2alpha) levels were inversely associated with serum albumin and total cholesterol (r = -0.31 and r = -0.28, respectively; p < 0.05). CONCLUSIONS: We conclude that ESRD on both HD and CAPD is associated with increased formation of F(2)-isoprostanes, a correlate of enhanced lipid peroxidation. We also found that plasma 8-iso-PGF(2alpha) was casually related to some acute phase reactant proteins such as serum CRP, albumin and haptoglobin. This may provide an important biochemical link between lipid peroxidation, inflammation and accelerated atherosclerosis in the uremic milieu.