Quantitative phosphoproteomic analysis of early seed development in rice (Oryza sativa L.)

Rice (Oryza sativa L.) seed serves as a major food source for over half of the global population. Though it has been long recognized that phosphorylation plays an essential role in rice seed development, the phosphorylation events and dynamics in this process remain largely unknown so far. Here, we report the first large scale identification of rice seed phosphoproteins and phosphosites by using a quantitative phosphoproteomic approach. Thorough proteomic studies in pistils and seeds at 3, 7 days after pollination resulted in the successful identification of 3885, 4313 and 4135 phosphopeptides respectively. A total of 2487 proteins were differentially phosphorylated among the three stages, including Kip related protein 1, Rice basic leucine zipper factor 1, Rice prolamin box binding factor and numerous other master regulators of rice seed development. Moreover, differentially phosphorylated proteins may be extensively involved in the biosynthesis and signaling pathways of phytohormones such as auxin, gibberellin, abscisic acid and brassinosteroid. Our results strongly indicated that protein phosphorylation is a key mechanism regulating cell proliferation and enlargement, phytohormone biosynthesis and signaling, grain filling and grain quality during rice seed development. Overall, the current study enhanced our understanding of the rice phosphoproteome and shed novel insight into the regulatory mechanism of rice seed development.

The association between ankle-brachial index and asymptomatic cranial-carotid stenosis: a population-based, cross-sectional study of 5440 Han Chinese

BACKGROUND AND PURPOSE

Routine screening for asymptomatic cranial-carotid stenosis (ACCS) is controversial and recommendation in clinical practice is vague. The ankle-brachial index (ABI) is reported as a predictor for cardiovascular disease. However, there is a scarcity of data about the association between abnormal ABI and ACCS. A population-based cross-sectional study was conducted to explore the relationship between ABI and ACCS.

METHODS

A sample of 5440 Chinese adults aged 40-94 years old was recruited from 2010 to 2011. The ABI was measured using a portable Doppler device and ACCS was evaluated by bilateral carotid duplex ultrasound and portable examination devices. A logistic regression model was used to analyse the association between ABI and ACCS after adjusting for potential confounding factors.

RESULTS

A low ABI was associated with ACCS [odds ratio (OR) 1.95, 95% confidence interval (CI) 1.42-2.67] after adjusting for potential confounders. When the data were stratified by age and sex, the correlation remained statistically significant in the male (OR 2.32, 95% CI 1.60-3.37) and elderly (OR 3.07, 95% CI 1.97-4.78) subgroups compared to the female (OR 1.26, 95% CI 0.67-2.39) and middle-aged groups (OR 1.27, 95% CI 0.77-2.12), respectively.

CONCLUSION

This study demonstrated that low ABI is a significant risk factor for ACCS in male and elderly Chinese adults.

Analysis of Road Traffic Injuries by Road User Type in Chongqing, China

Objective

Road traffic injuries are caused by many different factors. This study aimed to analyse road user type information in Chongqing, China in order to develop prevention strategies as well as treatment protocols.

Methods

Data from road traffic crashes from Chongqing, China were collected prospectively over a seven-year period (2000 to 2006). The data included the road user type, description of the injury, mortality and Abbreviated Injury Scale. Prevalence and cross-tabulations were included in the analysis.

Results

Forty-nine percent of deaths were pedestrians and 27.84% of deaths were drivers. Head injuries (26.49%) of pedestrians were higher than those of drivers and passengers. Thoracic injuries (22.78%) and spinal injuries (4.44%) of injured passengers were higher than those of drivers and pedestrians. There were significant differences in road user types in both injury severity and injury regions.

Conclusions

The distribution of road traffic injuries in Chongqing, China is different from that in developed countries and other developing countries. In managing traffic injuries, it is necessary to examine other regions besides the head according to the road user type, such as facial injuries of drivers and passengers, and chest and spinal injuries of passengers.

Magnetic field enhanced upconversion luminescence and magnetic–optical hysteresis behaviors in NaYF4: Yb, Ho nanoparticles

A magnetic field induces the enhancement of upconversion luminescence and magnetic–optical hysteresis behaviors in NaYF₄: 20% Yb, 1% Ho nanoparticles.

Decreased Npas4 and Arc mRNA Levels in the Hippocampus of Aged Memory-Impaired Wild-Type But Not Memory Preserved 11β-HSD1 Deficient Mice

Mice deficient in the glucocorticoid-regenerating enzyme 11β-HSD1 resist age-related spatial memory impairment. To investigate the mechanisms and pathways involved, we used microarrays to identify differentially expressed hippocampal genes that associate with cognitive ageing and 11β-HSD1. Aged wild-type mice were separated into memory-impaired and unimpaired relative to young controls according to their performance in the Y-maze. All individual aged 11β-HSD1-deficient mice showed intact spatial memory. The majority of differentially expressed hippocampal genes were increased with ageing (e.g. immune/inflammatory response genes) with no genotype differences. However, the neuronal-specific transcription factor, Npas4, and immediate early gene, Arc, were reduced (relative to young) in the hippocampus of memory-impaired but not unimpaired aged wild-type or aged 11β-HSD1-deficient mice. A quantitative reverse transcriptase-polymerase chain reaction and in situ hybridisation confirmed reduced Npas4 and Arc mRNA expression in memory-impaired aged wild-type mice. These findings suggest that 11β-HSD1 may contribute to the decline in Npas4 and Arc mRNA levels associated with memory impairment during ageing, and that decreased activity of synaptic plasticity pathways involving Npas4 and Arc may, in part, underlie the memory deficits seen in cognitively-impaired aged wild-type mice.

Data set from a comprehensive phosphoproteomic analysis of rice variety IRBB5 in response to bacterial blight

Bacterial blight (BB) caused by Xanthomonas oryzae pv. oryzae (Xoo) has become one of the most devastating diseases for rice, a major food source for over half of the world populations. To investigate the roles of protein phosphorylation in rice bacterial blight resistance, a quantitative phosphoproteomic study was conducted in rice variety IRBB5 at 0 h and 24 h after Xoo infection. 2367 and 2223 phosphosites on 1334 and 1297 representative proteins were identified in 0 h and 24 h after Xoo infection, respectively, out of which 762 proteins were found to be differentially phosphorylated. In associated with the published article “A comprehensive quantitative phosphoproteome analysis of rice in response to bacterial blight” in BMC Plant Biology (Hou et al., 2015) [1], this dataset article provided the detailed information of experimental designing, methods, features as well as the raw data of mass spectrometry (MS) identification. The MS proteomics data could be fully accessed from the ProteomeXchange Consortium with the dataset identifier PXD002222.

Individual differences in rumination in healthy and depressive samples: association with brain structure, functional connectivity and depression

BACKGROUND

Rumination is an important cognitive risk factor for onset and relapse of depression. However, no studies have employed a dimensional approach in investigating the neural correlates of rumination and the relationship with depression.

METHOD

Non-clinical healthy subjects (n = 306), who completed the classical rumination and depression scales, were studied using voxel-based morphometry and regional homogeneity (ReHo). Subsequently, mediation analysis was conducted to examine the influence of rumination on the relationship between brain structure and depression. Moreover, depressive patients (n = 60) and a control group (n = 63) of comparable age and education were studied with regions of interest that were identified in the healthy individuals.

RESULTS

For healthy individuals, regional grey-matter volume (rGMV) of dorsolateral prefrontal cortex (DLPFC) and parahippocampal gyrus (PHG) were positively correlated with rumination. In addition, rumination had a mediating effect on the relationship between the DLPFC and PHG and depression. Moreover, ReHo analysis showed that rumination had a significantly negative correlation with functional homogeneity of DLPFC. However, compared to the control group, depressed patients showed significant decrease of rGMV in the DLPFC and PHG and there was a significant negative correlation between DLPFC volume and depressive rumination.

CONCLUSIONS

Increased DLPFC volume (decreased ReHo) in healthy individuals while decreased in depression indicated the trend of DLPFC from inefficient inhibition ('overload state') to impaired regulatory mechanism ('paralysis state'). This finding might elucidate when and why healthy individuals would develop sustained negative mood and depression eventually.

Risk factors for BK virus infection and BK virus-associated nephropathy under the impact of intensive monitoring and pre-emptive immunosuppression reduction

BACKGROUND

BK virus (BKV) nephropathy (BKVN) is an increasingly recognized cause of kidney allograft loss and is thought to be related to the newer, more potent immunosuppressive agents. However, the risk factors for different types of BKV infection under the impact of intensive monitoring and reduction of maintenance immunosuppression are not well understood.

METHODS

Quantitative BKV DNA surveillance in plasma/urine and cytological testing in urine were performed regularly within the first year post-transplantation in 229 kidney recipients. Patients with BK viremia and BKVAN treated with immunosuppression reduction were monitored for BKV every 3-6 months. All the patients were followed up for a minimum of 5 years to exclude later development of BKVAN. Potential variables were compared and analyzed using logistic regression model multivariate analysis to assess and rank the BKV infection-related factors.

RESULTS

Seventy-eight (34.1%) patients had decoy cells, 99 (43.2%) BK viruria, 38 (16.6%) BK viremia, and 7 (3.1%) BKVAN. Risk for decoy cells, BK viruria, and viremia, and BKVAN in univariate analyses were higher with tacrolimus (Tac) and deceased kidney donation. Multivariate analysis showed that Tac ([HR, 2.7; P = .008], [HR, 2.3; P = .016], [HR, 2.9; P = .032]) and deceased kidney donation ([HR, 2.5; P = .004], [HR, 2.6; P = .002], [HR, 2.1; P = .071]) were risk factors for BK decoy cells, BK viruria, and viremia, respectively. BKVAN was inclined to the patients with the combination of Tac and mycophenolate mofetil and longer BKV clearance time.

CONCLUSIONS

Tac and deceased kidney donation are independent risk factors for BKV infection under the impact of therapeutic drug monitoring.

Effects of oleic acid on SP-B expression and release in A549 cells

OBJECTIVE

Pulmonary surfactant-associated protein B (SP-B), which is synthesized and secreted by alveolar epithelial type II cells, is crucial for normal functioning of pulmonary surfactant. Degeneration of pulmonary surfactant is the essential cause of acute lung injury (ALI). ALI is often studied in animal models using oleic acid, and the effects of oleic acid on pulmonary surfactant and SP-B are not clear. In this study, we examined the effects of oleic acid on the A549 cell line which resembles the alveolar epithelial type II cells.

MATERIALS AND METHODS

A549 cells were exposed for 24 hours to 300, 400, 500 or 600 µM of oleic acid. Cell morphological changes were observed using an inverted microscope, and cell proliferation was quantified with the Cell Counting Kit-8. Extracellular SP-B levels were assessed by ELISA, whereas intracellular SP-B expression by Western blot.

RESULTS

Oleic acid caused dose-dependent changes in cell morphology of A549 cells and decreased their proliferation. This was accompanied by release of SP-B into extracellular supernatants and corresponding decrease of intracellular levels of this protein.

CONCLUSIONS

Oleic acid causes a dose-dependent injury to A549 cells, release of SP-B into extracellular compartment, and decrease of intracellular SP-B expression. Our findings provide mechanistic insights into animal modeling of ALI with oleic acid.

Intravaginal HPV DNA vaccination with electroporation induces local CD8+ T-cell immune responses and antitumor effects against cervicovaginal tumors

Therapeutic human papillomavirus (HPV) vaccines have the potential to inhibit the progression of an established HPV infection to precancer and cancer lesions by targeting HPV oncoproteins. We have previously developed a therapeutic DNA vaccine encoding calreticulin (CRT) linked to E7, CRT/E7 DNA vaccine, for use in the treatment of HPV-associated lesions. Since the transfection efficiency of DNA vaccines administered in vivo is typically low, we examined the use of electroporation as well as different routes of administration to enhance antigen-specific tumor control. We tested the effects of the CRT/E7 DNA vaccine administered intramuscularly or intravaginally, with or without electroporation, on the generation of CD8+ T-cell immunity and therapeutic antitumor effects in HPV16 E7-expressing cervicovaginal tumor-bearing mice. We found that intravaginal vaccination of CRT/E7 DNA followed by electroporation-induced potent E7-specific CD8(+) T-cell responses in the cervicovaginal tract, compared with intramuscular injection followed by electroporation. Furthermore, tumor-bearing mice vaccinated intravaginally followed by electroporation had an enhanced survival, antitumor effects and local production of IFN-γ+CD8+ T cells compared with those vaccinated intramuscularly with electroporation. Thus, we show that intravaginal CRT/E7 DNA vaccination followed by electroporation generates the most potent therapeutic antitumor effects against an orthotopic E7-expressing tumor model. The current study will have significant clinical implications once a clinically applicable electroporation device for intravaginal use becomes available.

Plasma pharmacokinetics of ceftiofur metabolite desfuroylceftiofur cysteine disulfide in holstein steers: application of nonlinear mixed-effects modeling

Eight clinically normal and drug-naïve Holstein steers were dosed with ceftiofur sodium at 2.2 mg/kg body weight intramuscularly. Doses were given at 24-h intervals for 5 days. Prior to the first dose and after all injections, blood samples were collected serially for determination of plasma concentrations of one of ceftiofur's main metabolites, desfuroylceftiofur cysteine disulfide (DCCD). A nonlinear mixed-effect model was used to analyze the plasma concentration data. A stochastic approximation expectation maximization (SAEM) algorithm in MONOLIX version 4.2.2 was used to approximate the likelihood of the nonlinear mixed-effect model and to estimate the population parameters. In addition, simulation studies were conducted to justify the model and demonstrate how to interpret the model parameters given different scenarios.

A comprehensive quantitative phosphoproteome analysis of rice in response to bacterial blight

BACKGROUND

Rice is a major crop worldwide. Bacterial blight (BB) caused by Xanthomonas oryzae pv. oryzae (Xoo) has become one of the most devastating diseases for rice. It has been clear that phosphorylation plays essential roles in plant disease resistance. However, the role of phosphorylation is poorly understood in rice-Xoo system. Here, we report the first study on large scale enrichment of phosphopeptides and identification of phosphosites in rice before and 24 h after Xoo infection.

RESULTS

We have successfully identified 2367 and 2223 phosphosites on 1334 and 1297 representative proteins in 0 h and 24 h after Xoo infection, respectively. A total of 762 differentially phosphorylated proteins, including transcription factors, kinases, epi-genetic controlling factors and many well-known disease resistant proteins, are identified after Xoo infection suggesting that they may be functionally relevant to Xoo resistance. In particular, we found that phosphorylation/dephosphorylation might be a key switch turning on/off many epi-genetic controlling factors, including HDT701, in response to Xoo infection, suggesting that phosphorylation switch overriding the epi-genetic regulation may be a very universal model in the plant disease resistance pathway.

CONCLUSIONS

The phosphosites identified in this study would be a big complementation to our current knowledge in the phosphorylation status and sites of rice proteins. This research represents a substantial advance in understanding the rice phosphoproteome as well as the mechanism of rice bacterial blight resistance.

Post-stereotactic radiosurgery brain metastases: a review

Stereotactic radiosurgery (SR) is a standard therapy for brain metastases. Radiation necrosis (RN) of the brain is a syndrome of brain coagulative and fibrinoid necrosis and cortical irritation that occurs following radiotherapy. RN following SR peaks in a delayed fashion at 9-12 months postprocedure. Vasogenic cerebral edema secondary to necrosis occurs and can affect surrounding brain function. No definitive non-invasive diagnostic study exists to differentiate post-SR RN from recurrent metastatic tumor. Magnetic resonance (MR) imaging, MR spectroscopy, positron emission tomography, and perfusion-weighted MR imaging have been used to evaluate RN and are discussed. Treatment options for post-SR brain metastases include observation, corticosteroids, pentoxifylline and vitamin E, bevacizumab, radiotherapy, laser-interstitial thermal therapy, and surgical resection.

Polyglycidol-based metal adhesion promoters

Hydrophilic adhesion promoters that facilitate intimate binding between metals and polymers are an important class of materials with a wide variety of applications in biomedical coatings. Currently, non-poly(meth-)acrylate based hydrophilic polymeric adhesives are unavailable. Here, we report the preparation of such adhesion-promoters based on linear polyglycidol for biomedical applications. The adhesion promoting polymer is prepared from partly phosphonoethylated polyglycidol in three steps. First, the remaining hydroxyl groups of the polyglycidol backbone are reacted with acryloyl chloride; secondly, the phosphonate groups are chemoselectively dealkylated using bromotrimethylsilane. Finally, the bis(trimethylsilyl)phosphonate intermediate is converted to the phosphonic acid through ethanolysis. The reaction conditions of each synthetic step are optimized individually and the products are characterized by ¹H, ³¹P NMR and SEC analysis. The optimized reaction conditions are applied to establish a straightforward one-pot reaction, resulting in an ethanolic formulation of the adhesion promoter, which can be used immediately for the coating application. Special attention is paid to the stability of the intermediates, the chemoselectivity of the reactions and the shelf-life of the product. ¹H NMR spectroscopy reveals hydrolytic instability of the product under ambient conditions; however, the polymers are sufficiently stable in dry ethanol for at least 14 days. The combination of this hydrophilic polymer with acrylate and phosphonic acid groups constitutes a versatile platform technology for the preparation of thin primer coatings on metal substrates for biomedical applications. The phosphonic acid residues assure strong binding to stainless steel wires and the acrylates can be addressed by UV light to enable crosslinking, thus improving mechanical stability and adhesion between the substrate and a biomedical hydrogel coating. The quality of the adhesion promotion to stainless steel wires is verified by using a lubricious, hydrogel top coat and by evaluating friction and wear resistance of this total coating system. Constant values for friction and wear are obtained, proving the applicability of phosphonic acid-functionalized polyglycidols as metal adhesion promoters for biomedical applications.

Folic acid supplementation and dietary folate intake, and risk of preeclampsia

BACKGROUND/OBJECTIVES

Folic acid supplementation has been suggested to reduce the risk of preeclampsia. However, results from few epidemiologic studies have been inconclusive. We investigated the hypothesis that folic acid supplementation and dietary folate intake before conception and during pregnancy reduce the risk of preeclampsia.

SUBJECTS/METHODS

A birth cohort study was conducted in 2010-2012 at the Gansu Provincial Maternity & Child Care Hospital in Lanzhou, China. A total of 10,041 pregnant women without chronic hypertension or gestational hypertension were enrolled.

RESULTS

Compared with nonusers, folic acid supplement users had a reduced risk of preeclampsia (OR=0.61, 95% CI: 0.43-0.87). A significant dose-response of duration of use was observed among women who used folic acid supplemention during pregnancy only (P-trend=0.007). The reduced risk associated with folic acid supplement was similar for mild or severe preeclampsia and for early- or late-onset preeclampsia, although the statistical significant associations were only observed for mild (OR=0.50, 95% CI: 0.30-0.81) and late-onset (OR=0.60, 95% CI: 0.42-0.86) preeclampsia. The reduced risk associated with dietary folate intake during pregnancy was only seen for severe preeclampsia (OR=0.52, 95% CI: 0.31-0.87, for the highest quartile of dietary folate intake compared with the lowest).

CONCLUSIONS

Our study results suggest that folic acid supplementation and higher dietary folate intake during pregnancy reduce the risk of preeclampsia. Future studies are needed to confirm the associations.