Group 4 metal complexes bearing the aminoborane motif: origin of tandem ring-opening metathesis/vinyl-insertion polymerization

The origin of tandem ring-opening metathesis/vinyl-insertion polymerization using tailored group 4 metal complexes is outlined.

Improvement of the facial evenness of leave-on skincare products by a modified application method in Chinese women

OBJECTIVE

To understand the habits of Chinese women applying leave-on skincare products (LOSCP) and to improve female facial evenness of anti-ageing cosmetics through modifying facial skincare smear ways.

METHODS

A questionnaire on the method of applying LOSCP was distributed to 60 women with habit of using LOSCP. Their facial images before and after applying LOSCP were taken, and their positioning and grey value were used to analyse the effects of different applying methods on the uniformity of facial LOSCP.

RESULTS

LOSCP including anti-ageing cosmetics have been widely used among Chinese women for a long time. However, some women do not concern how to properly apply LOSCP. In our survey, the main focal points of the face are forehead, malar region, cheek, mouth corners and chin when they looking into the mirror, and mouth corners and inner canthus are often overlooked when applying cosmetic products. The image analysis found that after applying the LOSCP, the greyscale of the forehead, glabella, malar region, upper lip region and jaw changed significantly whereas that of canthus, mouth corners and lateral cheek region was not significantly different. Applying an improved smear method (11-point method)could significantly increase the grey values of various facial areas.

CONCLUSION

The way of Chinese women applying LOSCP may result in facial unevenness of skin products. By improving facial skincare smear method, one can make the products even in all facial areas, thereby ensuring the efficacy of anti-ageing cosmetics. Thus, further improvement and education regarding skincare is required.

Byars two-stage procedure for hypospadias after urethral plate transection

OBJECTIVE

To report on the outcomes of primary hypospadias repaired with the Byars two-stage procedure.

MATERIALS AND METHODS

Primary hypospadias repairs with the Byars two-stage procedure, between 2009 and 2012, were retrospectively reviewed. Medical charts were reviewed and analyzed. Follow up was at two weeks, three months, six months and one year after surgery. Complications, which included fistula, glans dehiscence, meatal stenosis, urethral stricture, diverticulum, recurrent penile curvature and others, were documented and analyzed.

RESULTS

One hundred and twenty-eight cases were included in the present study. The median follow up was 30 months (range 13-44 months). All flaps took successfully after the first stage. Overall complication rates were 11.8%. Complications included: seven cases of fistula; five glans dehiscence; two urethral strictures, which developed after fistula repair; and one concealed penis. No recurrent penile curvature was recorded.

CONCLUSIONS

The Byars two-stage procedure is an option for primary hypospadias when the urethral plate is transected. It had an 11.8% complication rate in this present study.

Upgrade of the electron beam ion trap in Shanghai

Over the last few years the Shanghai electron beam ion trap (EBIT) has been successfully redesigned and rebuilt. The original machine, developed under collaboration with the Shanghai Institute of Applied Physics, first produced an electron beam in 2005. It could be tuned with electron energies between 1 and 130 keV and beam current up to 160 mA. After several years of operation, it was found that several modifications for improvements were necessary to reach the goals of better electron optics, higher photon detection, and ion injection efficiencies, and more economical running costs. The upgraded Shanghai-EBIT is made almost entirely from Ti instead of stainless steel and achieves a vacuum of less than 10(-10) Torr, which helps to minimize the loss of highly changed ions through charge exchange. Meanwhile, a more compact structure and efficient cryogenic system, and excellent optical alignment have been of satisfactory. The magnetic field in the central trap region can reach up till 4.8 T with a uniformity of 2.77 × 10(-4). So far the upgraded Shanghai-EBIT has been operated up to an electron energy of 151 keV and a beam current of up to 218 mA, although promotion to even higher energy is still in progress. Radiation from ions as highly charged as Xe(53+, 54+) has been produced and the characterization of current density is estimated from the measured electron beam width.

Evaluation of coarsely ground wheat as a replacement for ground corn in the diets of lactating dairy cows

Eight multiparous Holstein cows (569±47 kg of BW; 84±17 DIM) were used to evaluate the effects of different levels of coarsely ground wheat (CGW) as replacements for ground corn (GC) in diets on feed intake and digestion, ruminal fermentation, lactation performance, and plasma metabolites profiles in dairy cows. The cows were settled in a replicated 4×4 Latin square design with 3-wk treatment periods; four cows in one of the replicates were fitted with rumen cannulas. The four diets contained 0, 9.6, 19.2, and 28.8% CGW and 27.9, 19.2, 9.6, and 0% GC on dry matter (DM) basis, respectively. Increasing dietary levels of CGW, daily DM intake tended to increase quadratically (p = 0.07); however, apparent digestibility of neutral detergent fiber (NDF) and acid detergent fiber (ADF) were significantly decreased (p<0.01) in cows fed the 28.8% CGW diets. Ruminal pH remained in the normal physiological range for all dietary treatments at all times, except for the 28.8% CGW diets at 6 h after feeding; moreover, increasing dietary levels of CGW, the daily mean ruminal pH decreased linearly (p = 0.01). Increasing the dietary levels of CGW resulted in a linear increase in ruminal propionate (p<0.01) and ammonia nitrogen (NH3-N) (p = 0.06) concentration, while ruminal acetate: propionate decreased linearly (p = 0.03) in cows fed the 28.8% CGW diets. Milk production was not affected by diets; however, percentage and yield of milk fat decreased linearly (p = 0.02) when the level of CGW was increased. With increasing levels of dietary CGW, concentrations of plasma beta-hydroxybutyric acid (BHBA) (p = 0.07) and cholesterol (p<0.01) decreased linearly, whereas plasma glucose (p = 0.08), insulin (p = 0.02) and urea nitrogen (p = 0.02) increased linearly at 6 h after the morning feeding. Our results indicate that CGW is a suitable substitute for GC in the diets of dairy cows and that it may be included up to a level of 19.2% of DM without adverse effects on feed intake and digestion, ruminal fermentation, lactation performance, and plasma metabolites if the cows are fed fiber-sufficient diets.

Resveratrol induces antioxidant and heat shock protein mRNA expression in response to heat stress in black-boned chickens

This study investigated the effects of dietary resveratrol at 0, 200, 400, or 600 mg/kg of diet on the performance, immune organ growth index, serum parameters, and expression levels of heat shock protein (Hsp) 27, Hsp70, and Hsp90 mRNA in the bursa of Fabricius, thymus, and spleen of 42-d-old female black-boned chickens exposed to heat stress at 37 ± 2°C for 15 d. The results showed that heat stress reduced daily feed intake and BW gain; decreased serum glutathione (GSH), growth hormone, and insulin-like growth factor-1 levels; and inhibited GSH peroxidase (GSH-Px), superoxide dismutase (SOD), and catalase (CAT) activities compared with birds subjected to thermo-neutral circumstances. Chickens that were fed diets supplemented with resveratrol exhibited a linear increase in feed intake and BW gain (P < 0.001); serum GSH, growth hormone, and insulin-like growth factor-1 levels (P ≤ 0.01); and GSH-Px, SOD, and CAT activities (P < 0.001) compared with chickens that were fed diets without resveratrol during heat stress. In contrast, serum malonaldehyde concentrations were decreased (P < 0.001) in the chickens fed a resveratrol-supplemented diet. Heat stress also reduced (P < 0.05) the growth index of the bursa of Fabricus and spleen; however, it had no effect on the growth index of the thymus. The growth index of the bursa of Fabricius and spleen increased (P < 0.05) upon heat stress and coincided with an increase in supplemental resveratrol levels. The expression of Hsp27, Hsp70, and Hsp90 mRNA in the bursa of Fabricius and spleen were increased (P < 0.01), but those of Hsp27 and Hsp90 mRNA in thymus were decreased (P < 0.01) under heat stress compared with no heat stress. Resveratrol attenuated the heat stress-induced overexpression of Hsp27, Hsp70, and Hsp90 mRNA in the bursa of Fabricius and spleen and increased the low expression of Hsp27 and Hsp90 mRNA in thymus upon heat stress. The results suggest that supplemental resveratrol improves growth performance and reduces oxidative stress in heat-stressed black-boned chickens by increasing serum growth hormone concentrations and modulating the expression of heat shock genes in organs of the immune system.

Fragmentation mechanisms for methane induced by 55 eV, 75 eV, and 100 eV electron impact

The fragmentation of CH4 (2+) dications following 55 eV, 75 eV, and 100 eV electron impact double ionization of methane was studied using a cold target recoil-ion momentum spectroscopy. From the measured momentum of each recoil ion, the momentum of the neutral particles has been deduced and the kinetic energy release distribution for the different fragmentation channels has been obtained. The doubly charged molecular ions break up into three or more fragments in one or two-step processes, resulting in different signatures in the data. We observed the fragmentation of CH4 (2+) dications through different mechanisms according to the momentum of the neutral particles. For example, our result shows that there are three reaction channels to form CH2 (+), H(+), and H, one synchronous concerted reaction channel and two two-step reaction channels. For even more complicated fragmentation processes of CH4 (2+) dications, the fragmentation mechanism can still be identified in the present measurements. The slopes of the peak in the ion-ion coincidence spectra were also estimated here, as they are also related to the fragmentation mechanism.

Neural correlates of the abolished self-referential memory effect in schizophrenia

BACKGROUND

The self-referential memory (SRM) effect refers to the phenomenon that stimuli processed with reference to the self are better remembered than those referenced to others. Studies have shown that schizophrenia patients do not have this memorial advantage for self-referenced information. The current study investigated the electrophysiological mechanism of the abolished SRM effect in schizophrenia.

METHOD

Twenty schizophrenia patients and 22 controls were recruited to complete an SRM task. We used a high-time resolution event-related potential (ERP) technique to analyze the electrophysiological differences between patients and controls during self- and other-reflection processing.

RESULTS

Behavior data indicated that healthy controls had a typical SRM bias that was absent in the schizophrenia patients. ERP comparison between groups showed that the schizophrenia patients presented smaller voltages in both self- and other-reflection conditions in the 160-260 ms (P2 component) and 800-1200 ms (positive slow wave) time windows over the pre/frontal cortex. Furthermore, the N2 amplitudes (270-380 ms) differed between self- and other-reflection conditions in patients but not in normal controls. More importantly, we found that the P3 amplitudes in the parietal cortex correlated significantly with the SRM bias score in the patients (r = -0.688).

CONCLUSIONS

These results provide comprehensive and direct electrophysiological evidence for self- and other-reflective dysfunction in schizophrenia patients and contribute to our understanding of the underlying neural substrates of the abolished SRM effect in schizophrenia.

Design of an ultrahigh-energy-resolution and wide-energy-range soft X-ray beamline

A new ultrahigh-energy-resolution and wide-energy-range soft X-ray beamline has been designed and is under construction at the Shanghai Synchrotron Radiation Facility. The beamline has two branches: one dedicated to angle-resolved photoemission spectroscopy (ARPES) and the other to photoelectron emission microscopy (PEEM). The two branches share the same plane-grating monochromator, which is equipped with four variable-line-spacing gratings and covers the 20-2000 eV energy range. Two elliptically polarized undulators are employed to provide photons with variable polarization, linear in every inclination and circular. The expected energy resolution is approximately 10 meV at 1000 eV with a flux of more than 3 × 10(10) photons s(-1) at the ARPES sample positions. The refocusing of both branches is based on Kirkpatrick-Baez pairs. The expected spot sizes when using a 10 µm exit slit are 15 µm × 5 µm (horizontal × vertical FWHM) at the ARPES station and 10 µm × 5 µm (horizontal × vertical FWHM) at the PEEM station. The use of plane optical elements upstream of the exit slit, a variable-line-spacing grating and a pre-mirror in the monochromator that allows the influence of the thermal deformation to be eliminated are essential for achieving the ultrahigh-energy resolution.

Ambrisentan improves the outcome of rats with liver transplantation partially through reducing nephrotoxicity

OBJECTIVE

Tacrolimus is a potent immunosuppressive agent mainly used for allogeneic solid organ transplantation. Although usage of tacrolimus led to a significant increase in short-term allograft survival, the long-term morbidity remains high. Endothelin-1 (ET-1) is reported to be associated with increased vascular resistance, CNI-induced nephrotoxicity and chronic rejection.

MATERIALS AND METHODS

In the present study, we first detected the serum and renal ET-1 level of rats treated by tacrolimus and found strong positive correlations were existed between the ET-1 level and the tacrolimus dosage and treated time. Furthermore, we studied the protective effect of ambrisentan in liver transplantation rats when co-administrated with tacrolimus. Healthy inbred male Wistar and Sprague-Dawley (SD) rats were used in this study. The post-operative general condition, transplantation survival time, hepatic aminotransferase, serum IFN-γ and level kidney injury biochemical index were recorded and compared to evaluate the immune response and outcomes in the recipient rats after liver transplantation.

RESULTS

Our results indicate that ambrisentan prevents the changes of ET-1 content in rats of non-operative treatment group and reduced the nephrotoxicity in the rats with liver transplantation. Rats from ambrisentan co-administration group exhibited good postoperative condition and prolonged survival.

CONCLUSIONS

Ambrisentan reverted some effects induced by tacrolimus in the kidney and indicated a positive potential for therapeutic benefit.

Associations of clinical features and prognosis with age at disease onset in patients with systemic lupus erythematosus

The objective of this study is to evaluate the association of clinical features and prognosis with age at disease onset in patients with systemic lupus erythematosus (SLE) in a large, multicenter Chinese cohort. Medical records of 1898 SLE inpatients from 15 hospitals were reviewed and classified into three groups according to their ages at disease presentation. Categorical data were analyzed by chi-square test and potentially associated factors were tested by multinomial logistic regression. Among the patients studied, 259 (13.6%) were juvenile onset (≤18 years), 1444 (76.1%) were early onset (>18 and ≤45 years) and 195 (10.3%) were late onset (>45 years). Whenever manifestations occurred, most patients (>80%) were diagnosed within two years. Juvenile-onset patients were more likely to be untreated before admission ( p < 0.001) and have mucocutaneous manifestations ( p < 0.001), but musculoskeletal symptoms ( p < 0.05) and leukopenia ( p < 0.05) were less frequent, while comorbidities were much higher in patients with late-onset SLE ( p < 0.001). Neuropsychiatric, cardiopulmonary, renal and gastrointestinal involvement, disease activity index and damage scores were similar among three groups. Anti-Sm antibodies were less prevalent in late-onset patients ( p < 0.05) and antimalarial drugs were more often applied to juvenile-onset patients ( p < 0.001). As expected, mortality was elevated in the late-onset SLE group ( p < 0.05), in which nearly half died of infections, which was much higher than those in the other two groups ( p < 0.001). Logistic regression confirmed that patients with juvenile- and early-onset disease were associated with high incidence of being untreated prior to admission, and with low incidence of comorbidities as well as deaths caused by infection compared to patients with late-onset lupus. Interestingly, our data showed that more patients with late-onset disease had a SLEDAI score change of >7 at discharge. In conclusion, age at onset has an impact on SLE disease status, and infection is the main cause of death in those with late-onset lupus. Considering that the late-onset patients had simultaneously easily controllable diseases and high incidence of comorbidities, a different treatment strategy from younger patients should be considered.

Isolation and characterization of two VpYABBY genes from wild Chinese Vitis pseudoreticulata

The establishment of abaxial-adaxial polarity is an important feature of the development of lateral organs in plants. Members of the YABBY gene family may be specific to seed-plant-specific transcriptional regulators that play critical roles in promoting abaxial cell fate in the model eudicot, Arabidopsis thaliana. However, recent study has shown that the roles of YABBY genes are not conserved in the development of angiosperms. The establishment of abaxial-adaxial polarity has not been studied in perennial fruit crops. Grapes are an important fruit crop in many regions of the world. Investigating YABBY genes in grapevines should help us to discover more about the key genetic and molecular pathways in grapevine development. To understand the characterization of YABBY genes in grapevines, two YABBY genes, VpYABBY1 (GenBank accession No. KC139089) and VpYABBY2 (GenBank accession No. KC139090), were isolated from the wild Chinese species Vitis pseudoreticulata. Both of these encode YABBY proteins. Sequence characterization and phylogenetic analyses show that VpYABBY1 is group classified into the FIL subfamily while VpYABBY2 is a member of the YAB2 subfamily of Arabidopsis thaliana. Subcellular localization analysis indicates that VpYABBY1 and VpYABBY2 proteins are localized in the nucleus. Tissue specific expressional analysis reveals that VpYABBY1 is expressed strongly in young leaves of grape but only weakly in the mature leaves. Meanwhile, VpYABBY2 is expressed in grape stems, flowers, tendrils, and leaves. Transgenic Arabidopsis plants ectopically expressing VpYABBY1 caused the partial abaxialization of the adaxial epidermises of leaves, behaving similarly to those over-expressing FIL or YAB3 with abaxialized lateral organs. By contrast, ectopic expression of VpYABBY2 in Arabidopsis did not cause any alteration in the adaxial-abaxial polarity. Sequence characterization and phylogenetic analysis revealed that VpYABBY1 and VpYABBY2 are group-classified into two different subfamilies. They have diverged functionally in the control of lateral organ development. VpYABBY1 may have a function in leaf development, while VpYABBY2 may play a specific role in carpel development and grape berry morphogenesis. It is further possible that during the evolution of different species, YABBY family members have preserved different expression regulatory systems and functions.

Association of serum arginase I with L-arginine, 3-nitrotyrosine, and exhaled nitric oxide in healthy Japanese workers

The associations of serum arginase I with serum L-arginine, serum 3-nitrotyrosine, and fractional exhaled nitric oxide (FENO) were evaluated cross-sectionally in healthy Japanese workers. The serum median (minimum-maximum) levels of arginase I, 3-nitrotyrosine, and FENO in healthy people (n = 130) were 14.6 (0.94-108.1) ng/mL, 81.0 (0.27-298.6) pmol/mg protein, and 14.0 (5.0-110.0) parts per billion, respectively. Significant correlations of arginase I with FENO, L-arginine, 3-nitrotyrosine, and percent predicted forced expiratory volume in 1 s (FEV1 (% predicted)) were observed, and correlations of FENO with immunoglobulin E (IgE), NOx, arginase I, and sex and allergy were also observed. By multiple regression analysis, arginase I showed positive associations with FENO and 3-nitrotyrosine, and a negative association with L-arginine; and FENO showed positive associations with IgE and NO2(-) + NO3(-) (NOx), and a negative association with L-arginine, as well as an association with sex. Moreover, logistic regression analysis showed linear inverse associations of arginase I and 3-nitrotyrosine with L-arginine, and showed linear positive associations of FENO with IgE and NOx. It was concluded that serum arginase I might regulate serum L-arginine and 3-nitrotyrosine via L-arginine, and that IgE or NOx might regulate FENO in a healthy Japanese population.

Angiotensinogen gene variations and LV outflow obstruction in hypertrophic cardiomyopathy

BACKGROUND

Variations of angiotensinogen (AGT) gene have been associated with cardiac hypertrophy. We hypothesized that AGT gene polymorphism may play a modifier role in the diversity of left ventricular outflow obstruction.

METHODS

The polymorphisms of the AGT gene were genotyped in 225 patients with hypertrophic cardiomyopathy (HCM) and 243 age-and sex-matched healthy controls. The effect of the A and G alleles on the expression of the reporter gene were evaluated in vitro using dual-luciferase reporter assays.

RESULTS

Our results showed that the frequency of the A allele was higher in patients than in controls (50.2 % vs. 35.8 %, p < 0.05). Patients carrying the AA and AG genotypes had a higher proportion of left ventricular outflow obstruction (30.1 % vs. 17.0 %, p < 0.05) and heart failure (NYHA functional class III ~ IV, 35.4 % vs. 18.8 %, p < 0.05) than those carrying the GG genotype had. After adjusted for age, sex, the thickness of the interventricular septum, family history of HCM, and sudden death, the A allele conferred a 2.4-fold risk for left ventricular outflow obstruction than the GG genotype did (adjusted OR = 2.4, 95 %CI 1.2-4.8). The G allele suppressed the expression of the reporter gene significantly compared with the A allele (p < 0.05).

CONCLUSION

AGT gene variations may be genetic modifiers for the development of HCM.

Factors associated with acceptability of circumcision among male drug users in western China: a cross-sectional study

This study is aimed to investigate whether male circumcision (MC) is feasible among IDUs in China. 1304 drug users who attended methadone maintenance therapy clinics in Guangxi, Chongqing and Xinjiang were selected for participation by using convenience sampling, and completed a self-administered questionnaire. The factors associated with the acceptability of MC were examined via multiple logistic regression models. 45.2% (589/1304) of the participants reported an acceptance of MC. Many of the participants who were initially not willing to accept MC (715/1304) had changed their mind when they were informed that MC would reduce the risk of HIV and STDs (43.4%; 310/715), that MC is associated with few surgery-related complications (23.1%; 165/715), that the surgical procedure could be arranged free of charge (20.1%, 144/715). In the multivariate analysis, higher acceptability of MC was associated with knowledge of the hazards of phimosis (OR=2.22), the presence of phimosis (OR=14.87), and knowledge that MC can prevent AIDS and STDs (OR=1.49); while lower acceptability was associated with residing in Chongqing province (OR=0.41) and an educational level of junior (OR=0.64) and senior high (OR=0.63) school. The MC policy targeting IDUs in China should take into account these factors associated with MC acceptability.

The differential contributions of herkogamy and dichogamy as mechanisms of avoiding self-interference in four self-incompatible Epimedium species

Self-interference is one of the most important selective forces in shaping floral evolution. Herkogamy and dichogamy both can achieve reductions in the extent of self-interference, but they may have different roles in minimizing self-interference in a single species. We used four self-incompatible Epimedium species to explore the roles of herkogamy and dichogamy in avoiding self-interference and to test the hypothesis that herkogamy and dichogamy may be separated and become selected preferentially in the taxa. Two species (E. franchetii and E. mikinorii) expressed strong herkogamy and weak protogyny (adichogamy), whereas another two species (E. sutchuenense and E. leptorrhizum) expressed slight herkogamy and partial protandry. Field investigations indicated that there was no physical self-interference between male function and female function regarding pollen removal and pollen deposition in all species. Self-pollination (autonomous or facilitated) was greater in species with slight herkogamy than in those with strong herkogamy. Artificial pollination treatments revealed that self-pollination could reduce outcrossed female fertility in all species, and we found evidence that self-interference reduced seed set in E. sutchuenense and E. leptorrhizum in the field, but not in E. franchetii and E. mikinorii. These results indicate that well-developed herkogamy is more effective compared with dichogamy in avoiding self-interference in the four species. In genus Epimedium, herkogamy instead of dichogamy should be selected preferentially and evolved as an effective mechanism for avoiding self-interference and might not need to evolve linked with dichogamy.

The human MTHFR rs4846049 polymorphism increases coronary heart disease risk through modifying miRNA binding

BACKGROUND AND AIMS

Abnormal functioning of 5,10-methylenetetrahydrofolate reductase (MTHFR) enhances the risk for coronary heart disease (CHD). Here, we tested whether a single-nucleotide polymorphism (SNP) located in the 3' untranslated region (UTR) of MTHFR was associated with CHD susceptibility by affecting microRNAs binding.

METHODS AND RESULTS

We first analyzed in silico the SNPs localized in the 3' UTR of MTHFR for their ability to modify miRNA binding. We observed that rs4846049 (G > T) was a potential candidate SNP to modulate miRNAs:MTHFR mRNA complex, with the greatest changed binding free energy for has-miR-149. Based on luciferase analysis, hsa-miR-149 inhibited the activity of the reporter vector carrying -T allele, but not -G allele. We further conducted a case-control study (654 vs 455) in a Chinese Han population. rs4846049 was significantly associated with increased risk for CHD. In addition, the T allele was associated with decreased levels of HDL-cholesterol and apoA. Finally, we observed a reduced MTHFR protein level in peripheral blood mononuclear cells of CHD patients with TT carriers compared to GG carriers of rs4846049.

CONCLUSION

Our results suggest that rs4846049 (G > T) of MTHFR is associated with increased risk for CHD. We also identified a potentially pathogenetic mechanism of SNP-modified posttranscriptional gene regulation by miRNAs to MTHFR.

Epidemiological link between exposure to poultry and all influenza A(H7N9) confirmed cases in Huzhou city, China, March to May 2013

We analysed the association between influenza A(H7N9) confirmed cases and exposure to poultry in Huzhou city, China. All cases (n=12) had a history of direct exposure to poultry or live poultry markets. We detected A(H7N9)-positive poultry samples from each site that was epidemiologically associated with cases. None of the cases’ close contacts tested positive. After closure of the markets, no new cases were identified, suggesting an epidemiological link between poultry exposure and A(H7N9) virus infection.

Epidemiological link between exposure to poultry and all influenza A(H7N9) confirmed cases in Huzhou city, China, March to May 2013

Binary file ES_Abstracts_Final_ECDC.txt matches

16(th) IHIW: report of the MICA project

The MICA Project of the 16th International HLA and Immunogenetics Workshop was planned to improve the detection of specific antibodies against MICA antigens that develop in organ transplant recipients. It was organized as a serum exchange with 18 laboratories located in seven countries as participants. Each laboratory used the MICA screening reagents available to them. It was found that there were four different kits of Luminex beads conjugated with MICA antigens that could be used in these experiments. They were, kit BL, produced by Rainer Blasczyk in Hannover, Germany, containing 12 MICA antigens, the kit from Gen-Probe (GP), which included 28 MICA antigens, the beads from One Lambda (OL), consisting of ten antigens, and the beads produced in the laboratory of the organizers (ZS) consisting of 11 MICA antigens. The sera were all from transplant recipients and represented a spectrum of MICA-specific antibodies that are commonly found. All laboratories accurately could recognize which sera contained MICA antibodies. None failed to recognize the negative serum that was included in one of the shipments. While there were important differences in the specificities of MICA antigens recognized by the different kits, the results in laboratories using the same beads were remarkably similar. Feedback was given to the participants, and especially to the producers of the antibody detection kits, after each set of four sera was sent, and results were collected. Certain beads were replaced and results improved as can be seen in the results of the third shipment of sera. It is important for laboratories to be able to accurately determine the specificity of antibodies against MICA to know whether the antibodies are donor specific. Although complete consensus was not attained, some important errors were corrected, and a better understanding of how to accurately determine MICA allele-specific antibodies was developed.

Effect of mild hypothermia on breast cancer cells adhesion and migration

To explore the effect of mild hypothermia (35ºC) on breast cancer cells adhesion to vascular endothelial cells, a parallel plant flow chamber was used to observe the adhesion of human breast cancer cells MDA-MB-231 to endothelial cells Eahy926 under physiological flow at 35ºC and 37ºC, as well as the role of intercellular adhesion molecule 1 (ICAM-1) in this process. Further, the effect of mild hypothermia (35ºC) on migration of MDA-MB-231 was also studied. Our results show that mild hypothermia can inhibit the adhesion of tumor cells to endothelial cells and ICAM-1 plays an important role in this process. However, mild hypothermia inhibits breast cancer cell adhesion in a way independent on the change of ICAM-1 expression under our experimental conditions. Mild hypothermia can weaken the chemotaxis of breast cancer cells while it has no obvious effect on unidirectonal migration capacity. These results suggest that mild hypothermia could be used as a potentially adjunct treatment combined with surgery to decrease tumor cell adhesion and migration.

Protective effect of puerarin against beta-amyloid-induced oxidative stress in neuronal cultures from rat hippocampus: involvement of the GSK-3β/Nrf2 signaling pathway

Current evidence suggests that amyloid beta (Aβ) peptides may play a major role in the pathogenesis of Alzheimer's disease in part by eliciting oxidative stress. Puerarin, a major isoflavone glycoside from Kudzu root (Pueraria lobata), has been reported to exert estrogen-like and antioxidant activities. The central hypothesis guiding this study is that puerarin will prevent or at least markedly attenuate Aβ(25-35)-induced excess production of reactive oxygen species (ROS) by interrupting glycogen synthase kinase-3β (GSK-3β) signaling. In this study, we demonstrate that pretreatment of primary hippocampal neurons with puerarin significantly reduced Aβ(25-35)-induced oxidative stress characterized by scavenging of ROS and inhibiting lipid peroxidation. Puerarin induced expression of nuclear Nrf2 protein, but not in the Nrf2 mRNA level, and increased heme oxygenase-1 (HO-1) levels at levels of transcription and translation. Puerarin-induced Serine 9 phosphorylation of GSK-3β was blocked by lithium chloride treatment in primary hippocampal neurons, indicating the participation of the GSK-3β inactivation. This protective effect was partially reversed when GSK-3β were blocked by the chemical inhibitors such as lithium chloride. These results suggest puerarin as a phytoestrogen with potential of a possible therapeutic agent in neurodegenerative diseases involving oxidative stress.

Cellular and molecular responses of Salmonella Typhimurium to antimicrobial-induced stresses during the planktonic-to-biofilm transition

AIM

To characterize the cellular and molecular properties of Salmonella Typhimurium exposed to antimicrobials in association with physicochemical property, biofilm formation ability and gene expression patterns.

METHODS AND RESULTS

The antimicrobial susceptibilities against Salmonella Typhimurium were evaluated to determine the MICs of allyl isothiocyanate (AITC), thymol, eugenol and polyphenol. Cell surface hydrophobicity, aggregation and biofilm formation assays were conducted to assess the physicochemical properties of Salm. Typhimurium treated with sublethal concentrations (SLC(2D) ) of antimicrobials. The expression patterns of adhesion-related genes (adrA, csgD, fimA and lpfE), virulence-related genes (hilA and stn) and efflux-related genes (acrA, acrB, ompD and tolC) were evaluated by real-time RT-PCR. Thymol exhibited the highest antimicrobial activity against Salm. Typhimurium planktonic, biofilm and dispersed cells, showing 0·18, 0·96 and 0·42 mg ml(-1) of SLC(2D) values, respectively. The antimicrobial-treated Salm. Typhimurium showed low hydrophobicity. The highest auto-aggregation ability (67%) of polyphenol-treated Salm. Typhimurium was positively associated with the enhanced ability to form biofilms. The csgD, fimA, hilA and lpfE genes were up-regulated in the polyphenol-treated Salm. Typhimurium planktonic and biofilm cells.

CONCLUSION

The results suggest that the antimicrobial resistance and virulence potential varied depending on the physiological states of Salm. Typhimurium during the transition from planktonic to biofilm cell growth.

SIGNIFICANCE AND IMPACT OF THE STUDY

This study can expand our understanding of cellular and molecular mechanisms of biofilm formation and also provide useful information for reducing biofilm-associated virulence potential.

A subpopulation of CD24⁺ cells in colon cancer cell lines possess stem cell characteristics

Cancer stem cells (CSCs) have been shown to contribute to the resistance and relapse in a range of cancer types such as breast cancer and glioma. However, colon cancer stem cells remain poorly characterized. Here we reported that CD24+ subpopulation in colon cancer cell lines HCT116 and SW480 exhibited cancer stem cell-like characteristics. Using flow cytometry candidate CSCs markers were selected after initial screening of known CSCs markers from other types of cancer on colon cancer cell lines HCT116, SW480 and HT29. CD24 was expressed in the minority of bulk cell population of HCT116 and SW480 cell lines. Moreover, functional tests demonstrated that CD24+ cells exhibited enhanced chemotherapy-resistance, self-renewal and tumorigenic capacity both in vitro and in vivo, compared to CD24- subpopulations. These results suggest that CD24+ subpopulation in colon cancer cell lines HCT116 and SW480 exhibits CSCs like characteristics, and represents a nice model to study and develop effective strategies to overcome chemo-resistance and relapse of colon cancer.

DNA-PK, ATM and ATR collaboratively regulate p53-RPA interaction to facilitate homologous recombination DNA repair

Homologous recombination (HR) and nonhomologous end-joining (NHEJ) are two distinct DNA double-strand break (DSB) repair pathways. Here we report that DNA-dependent protein kinase (DNA-PK), the core component of NHEJ, partnering with DNA-damage checkpoint kinases ataxia telangiectasia mutated (ATM) and ATM- and Rad3-related (ATR), regulates HR repair of DSBs. The regulation was accomplished through modulation of the p53 and replication protein A (RPA) interaction. We show that upon DNA damage, p53 and RPA were freed from a p53-RPA complex by simultaneous phosphorylations of RPA at the N-terminus of RPA32 subunit by DNA-PK and of p53 at Ser37 and Ser46 in a Chk1/Chk2-independent manner by ATR and ATM, respectively. Neither the phosphorylation of RPA nor of p53 alone could dissociate p53 and RPA. Furthermore, disruption of the release significantly compromised HR repair of DSBs. Our results reveal a mechanism for the crosstalk between HR repair and NHEJ through the co-regulation of p53-RPA interaction by DNA-PK, ATM and ATR.

First Report of a Leaf Spot on Pepper Caused by Cladosporium oxysporum in China

Pepper (Capsicum annuum L.) is an important vegetable crop grown in Liaoning Province of China. In June 2009, leaf spotting was observed on hot pepper cv. 37-74 in Wafangdian County of Liaoning Province. By August 2011, the disease had spread to Pulandian and Donggang Counties. Symptoms initially appeared on both sides of leaves as pinpoint chlorotic spots that enlarged and developed into irregular, brown lesions, 1 to 8 mm in diameter. To identify the pathogen, leaf pieces (3 to 5 mm) taken at the edge of lesions with both infected and healthy portions were surface disinfected by placing them in 75% ethanol for 5 s, then transferred to a 0.1% aqueous mercuric chloride solution for 30 s and rinsed with sterilized water three times. The sections were placed on potato dextrose agar (PDA) at 25°C in the dark. Ten pure fungal cultures were obtained from single spores. For growth rate determination and morphological description of colonies, single conidial isolates were inoculated on PDA, malt extract agar (MEA), and oatmeal agar (OA), and incubated at 25°C for 14 days in darkness. For studies of microscopic morphology, isolates were grown on synthetic nutrient agar (SNA) in slide cultures. Colonies grew up to 77 to 80 mm in diameter on PDA, 62 to 66 mm on MEA, and 58 to 60 mm on OA after 14 days. Conidiophores were straight to slightly flexuous. Conidia ranged in shape from subglobose or ovoid to subcylindrical. Macronematous conidiophores measured 40 to 670 × 3 to 5.5 μm with swellings, micronematous conidiophores 15 to 137 × 1.5 to 3.5 μm, terminal conidia 2 to 4 × 2 to 3 μm, and intercalary conidia 4 to 10 × 2.5 to 4 μm. Ramoconidia were rarely observed. Secondary ramoconidia were zero- to one-septate and measured 5.2 to 14.8 × 2.4 to 4 μm. On the basis of these characteristics, the isolates were identified as Cladosporium oxysporum (1). The internal transcribed spacer (ITS) region from isolate W10-02 was amplified using primers ITS1 and ITS4 and sequenced (GenBank Accession No. JQ775499). The 525-bp amplicons had 99% identity to C. oxysporum (GenBank Accession No. EF029816). On the basis of morphological characteristics and nucleotide homology, the isolate was identified as C. oxysporum. Koch's postulates were fulfilled in the laboratory on pepper leaves inoculated with C. oxysporum conidial suspensions (10⁷ conidia ml^-1). Eight inoculated 4-week-old seedlings were incubated under moist conditions for 8 to 10 days at 25°C. All leaf spots that developed on inoculated leaves were similar in appearance to those observed on diseased pepper in the field. C. oxysporum was reisolated from lesions and its identity was confirmed by morphological characteristics. C. oxysporum was first reported as a pathogen of pepper in the Sultanate of Oman (2). To our knowledge, this is the first report of C. oxysporum causing leaf spot on pepper in China. The outbreak and spread of this disease may decrease the yield of pepper in the northern regions of China. More studies are needed on the management strategy including the resistance of pepper cultivars against C. oxysporum. References: (1) K. Bensch et al. 2010. Stud. Mycol. 67:1, 2010. (2) A. M. Hammouda. Plant Dis. 76:536, 1992.

Co-expression of VpROMT gene from Chinese wild Vitis pseudoreticulata with VpSTS in tobacco plants and its effects on the accumulation of pterostilbene

Plant secondary metabolites, such as stilbenes, have fungicidal potential and have been found in several plant species. Stilbenes in grapevine, such as resveratrol and pterostilbene, have recently attracted much attention, they are not only helping the plant to fight against pathogen attack, but they are also being widely used as ingredients of fungicide, anti-inflammatory drugs, antioxidant, and anti-infective agents. However, resveratrol O-methyltransferase gene, related with the synthesis of pterostilbene from resveratrol, has not been characterized effectively from Chinese wild Vitis pseudoreticulata. In this study, a candidate of resveratrol O-methyltransferase gene designated as VpROMT was isolated from a powdery mildew-resistant Chinese wild V. pseudoreticulata 'Baihe-35-1', and characterization studies were performed. Expression studies showed that VpROMT was predominantly expressed in developing roots yet not found in the leaves, stems, nor tendrils when the plants are not challenged. Results of qRT-PCR showed that VpROMT was rapidly induced by Erysiphe necator in V. pseudoreticulata and by methyl-jasmonate, UV-irradiation in suspension culture cells of Vitis romanetii. The expression level varies in different tissues of grapevine, which MeJA and UV-C treatment significantly upregulated the expression of VpROMT gene while UV-B treatment failed to. Co-expression of VpROMT and grapevine stilbene synthase (VpSTS) gene leads to the accumulation of pterostilbene in leaves of tobacco (Nicotiana tabacum) indicating that VpROMT was able to catalyze the biosynthesis of pterostilbene from resveratrol in over-expression transgenic tobacco plants.

Low dose IR-induced IGF-1-sCLU expression: a p53-repressed expression cascade that interferes with TGFβ1 signaling to confer a pro-survival bystander effect

Inadvertent mammalian tissue exposures to low doses of ionizing radiation (IR) after radiation accidents, remediation of radioactive-contaminated areas, space travel or a dirty bomb represent an interesting trauma to an organism. Possible low-dose IR-induced bystander effects could impact our evaluation of human health effects, as cells within tissue are not equally damaged after doses of IR ≤10 cGy. To understand tissue responses after low IR doses, we generated a reporter system using the human clusterin promoter fused to firefly luciferase (hCLUp-Luc). Secretory clusterin (sCLU), an extracellular molecular chaperone, induced by low doses of cytotoxic agents, clears cell debris. Low-dose IR (≥2 cGy) exposure induced hCLUp-Luc activity with peak levels at 96 h, consistent with endogenous sCLU levels. As doses increased (≥1 Gy), sCLU induction amplitudes increased and time-to-peak response decreased. sCLU expression was stimulated by insulin-like growth factor-1, but suppressed by p53. Responses in transgenic hCLUp-Luc reporter mice after low IR doses showed that specific tissues (that is, colon, spleen, mammary, thymus and bone marrow) of female mice induced hCLUp-Luc activity more than male mice after whole body (≥10 cGy) irradiation. Tissue-specific, non-linear dose- and time-responses of hCLUp-Luc and endogenous sCLU levels were noted. Colon maintained homeostatic balance after 10 cGy. Bone marrow responded with delayed, but prolonged and elevated expression. Intraperitoneal administration of α-transforming growth factor (TGF)β1 (1D11), but not control (13C4) antibodies, immediately following IR exposure abrogated CLU induction responses. Induction in vivo also correlated with Smad signaling by activated TGFβ1 after IR. Mechanistically, media with elevated sCLU levels suppressed signaling, blocked apoptosis and increased survival of TGFβ1-exposed tumor or normal cells. Thus, sCLU is a pro-survival bystander factor that abrogates TGFβ1 signaling and most likely promotes wound healing.

A very low energy compact electron beam ion trap for spectroscopic research in Shanghai

In this paper, a new compact low energy electron beam ion trap, SH-PermEBIT, is reported. This electron beam ion trap (EBIT) can operate in the electron energy range of 60-5000 eV, with a current density of up to 100 A/cm(2). The low energy limit of this machine sets the record among the reported works so far. The magnetic field in the central drift tube region of this EBIT is around 0.5 T, produced by permanent magnets and soft iron. The design of this EBIT allows adjustment of the electron gun's axial position in the fringe field of the central magnetic field. This turned out to be very important for optimizing the magnetic field in the region of the electron gun and particularly important for low electron beam energy operation, since the magnetic field strength is not tunable with permanent magnets. In this work, transmission of the electron beam as well as the upper limit of the electron beam width under several conditions are measured. Spectral results from test operation of this EBIT at the electron energies of 60, 315, 2800, and 4100 eV are also reported.