Studies on optimum harvest time for hybrid rice seed.

BACKGROUND: Timely harvest is critical for hybrid rice to achieve maximum seed viability, vigor and yield. However, how to predict the optimum harvest time has been rarely reported so far. RESULTS: The seed vigor of Zhuliangyou 06 (ZLY06) increased and reached the highest level at 20 days after pollination (DAP), when seed moisture content had a lower value, which was maintained until final seed maturation. For Chunyou 84 (CY84), seed vigor, fresh and dry weight had relatively high values at 25 DAP, when seed moisture content reached the lowest value and changed slightly from 25 to 55 DAP. In both hybrid rice varieties, seed glume chlorophyll content declined rapidly from 10 to 30 DAP and remained at a very low level after 35 DAP. Starch content exhibited an increasing trend during seed maturation, while both soluble sugar content and amylase activity decreased significantly at the early stages of seed development. Moreover, correlation analyses showed that seed dry weight, starch content and superoxide dismutase activity were significantly positively correlated with seed vigor. In contrast, chlorophyll content, moisture content, soluble sugar, soluble protein, abscisic acid, gibberellin content, electrical conductivity, catalase and ascorbate peroxidase activities were significantly negatively correlated with seed vigor. Physiological and biochemical parameters were obviously more closely related with seed vigor than with seed germinability during seed development. CONCLUSION: Seed vigor could be better used as a comprehensive factor to predict the optimum seed harvest time. It is suggested that for ZLY06 seeds could be harvested as early as 20 DAP, whereas for CY84 the earliest optimum harvest time was 25 DAP. © 2016 Society of Chemical Industry.

Determination of arsenic species in Solanum Lyratum Thunb using capillary electrophoresis with inductively coupled plasma mass spectrometry.

A simple and highly efficient interface to couple capillary electrophoresis with inductively coupled plasma mass spectrometry by a microflow polyfluoroalkoxy nebulizer and a quadruple ion deflector was developed in this study. By using this interface, six arsenic species, including arsenite, arsenate, monomethylarsonic acid, dimethylarsinic acid, arsenobetaine, and arsenocholine, were baseline-separated and determined in a single run within 11 min under the optimized separation conditions. The instrumental detection limit was in the range of 0.02-0.06 ng/mL for the six arsenic compounds. Repeatability expressed as the relative standard deviation (n = 5) of both migration time and peak area were better than 2.5 and 4.3% for six arsenic compounds. The proposed method, combined with a closed-vessel microwave-assisted extraction procedure, was successfully applied for the determination of arsenic species in the Solanum Lyratum Thunb samples from Anhui province in China with the relative standard deviations (n = 5) ≤4%, method detection limits of 0.2-0.6 ng As/g and a recovery of 98-104%. The experimental results showed that arsenobetaine was the main speciation of arsenic in the Solanum Lyratum Thunb samples from different provinces in China, with a concentration of 0.42-1.30 µg/g.

Divergent Urinary Metabolic Phenotypes between Major Depressive Disorder and Bipolar Disorder Identified by a Combined GC-MS and NMR Spectroscopic Metabonomic Approach.

Bipolar disorder (BD) is a complex debilitating mental disorder that is often misdiagnosed as major depressive disorder (MDD). Therefore, a large percentage of BD subjects are incorrectly treated with antidepressants in clinical practice. To address this challenge, objective laboratory-based tests are needed to discriminate BD from MDD patients. Here, a combined gas chromatography-mass spectrometry (GC-MS)-based and nuclear magnetic resonance (NMR) spectroscopic-based metabonomic approach was performed to profile urine samples from 76 MDD and 43 BD subjects (training set) to identify the differential metabolites. Samples from 126 healthy controls were included as metabolic controls. A candidate biomarker panel was identified by further analyzing these differential metabolites. A testing set of, 50 MDD and 28 BD subjects was then used to independently validate the diagnostic efficacy of the identified panel using an area under the receiver operating characteristic curve (AUC). A total of 20 differential metabolites responsible for the discrimination between MDD and BD subjects were identified. A panel consisting of six candidate urinary metabolite biomarkers (propionate, formate, (R*,S*)2,3-dihydroxybutanoic acid, 2,4-dihydroxypyrimidine, phenylalanine, and ß-alanine) was identified. This panel could distinguish BD from MDD subjects with an AUC of 0.913 and 0.896 in the training and testing sets, respectively. These results reveal divergent urinary metabolic phenotypes between MDD and BD. The identified urinary biomarkers can aid in the future development of an objective laboratory-based diagnostic test for distinguishing BD from MDD patients.

Post-treatment of dextromethorphan on methamphetamine-induced drug-seeking and behavioral sensitization in rats.

In our previous study, we first demonstrated a significant effect of dextromethorphan (DM) on morphine-seeking behavior in morphine-dependent rats, when DM was given during morphine withdrawal. Using the same conditioned place preference (CPP) paradigm modified for measuring drug-seeking-related behavior, we further investigated the possible effect of DM on methamphetamine (MA)-seeking in MA-dependent rats. Our data showed that DM could also effectively suppress the drug-seeking behavior for MA, when administered during MA withdrawal. This suggests that DM may possess a pharmacological property to prevent drug-seeking behavior for addictive drugs in general. To examine the action sites of DM in the brain, DM was microinjected into the VTA or the NAc, and tested for its effect on MA-seeking during withdrawal. Both intra-VTA and intra-NAc injections of DM were able to block the MA-seeking, suggesting that DM has a dual action sites. In our neurochemical results, intra-NAc injection of DM showed a clear reduction of DA turnover rate at the NAc and the mPFC in response to MA challenge during withdrawal, which matched with the behavioral results. However, intra-VTA injection of DM reduced the DA turnover rate at the mPFC but did not have effect on the DA turnover rate at the NAc. Although further investigations may be needed to verify the connection between our neurochemical and behavioral results, the present study highlights the therapeutic potential of DM in antidrug-seeking behavior of MA and that the mechanism could be related to its effect on the mesolimbic and mesocortical dopaminergic pathways.

Lipophilic ferulic acid derivatives protect PC12 cells against oxidative damage via modulating ß-amyloid aggregation and activating Nrf2 enzymes.

Ferulic acid (FA) has been shown to have a neuroprotective effect on Alzheimer's disease induced by amyloid-beta (Aß) neurotoxicity. This work aims to ascertain the structure-activity relationship of FA and its alkyl esters (FAEs) for evaluating the antioxidant activities in PC12 cells and Aß1-42 aggregation inhibitory activities in vitro, as well as the signaling mechanisms against oxidative stress elicited by Aß1-42 in PC12 cells. Our data showed that alterations in the subcellular localization and cytotoxicity of FAEs caused by the lipophilicity of FA were crucial when evaluating their antioxidant capacities. Pre-treating cells with butyl ferulate (FAC4) significantly attenuated Aß1-42-evoked intracellular ROS formation. Besides, FAC4 exhibited the highest Aß1-42 aggregation inhibitory effectiveness. The molecular docking results showed that FAC4 binds to amide NH in Gln15 and Lys16 via a hydrogen bond. Notably, FAC4 could upregulate antioxidant defense systems by modulating the Keap1-Nrf2-ARE signaling pathway. Identification of the functions of FAEs could be useful in developing food supplements or drugs for treating AD.

Synergistic antibacterial effect of ultrasound microbubbles combined with chitosan-modified polymyxin B-loaded liposomes on biofilm-producing Acinetobacter baumannii.

PURPOSE: Resistant strains of Acinetobacter baumannii (AB) that can form biofilms are resistant to polymyxin. Therefore, effective and safe polymyxin preparations against biofilm-producing AB are urgently needed. This study aims to prepare chitosan-modified polymyxin B-loaded liposomes (CLPs) and ultrasound microbubbles (USMBs) and then explore the synergistic antibacterial effects of USMBs combined with CLPs in vitro. METHODS: CLPs were prepared using a modified injection method, and microbubbles were prepared using a simple mechanical vibration method. Minimal biofilm inhibitory concentration (MBIC) of CLPs against resistant biofilm-producing AB was determined. Antibacterial activities of CLPs with or without USMBs were analyzed by crystal violet staining and resazurin assays to evaluate biofilm mass and viable counts, respectively. Then, the anti-biofilm effects of CLPs with or without USMBs on biofilm-producing AB were confirmed via scanning electron microscopy (SEM) analysis. RESULTS: We prepared CLPs that were 225.17±17.85 nm in size and carried positive charges of 12.64±1.44 mV. These CLPs, with higher encapsulation efficiency and drug loading, could exhibit a sustained release effect. We prepared microbubbles that were 2.391±0.052 µm in size and carried negative charges of -4.32±0.43 mV. The MBICs of the CLPs on the biofilm-producing AB was 8±2 µg/mL, while that of polymyxin B was 32±2 µg/mL. USMBs in combination with 2 µg/mL of polymyxin B could completely eliminate the biofilm-producing AB and achieve the maximum antimicrobial effects (P>0.05 vs sterile blank control). SEM imaging revealed some scattered bacteria without a biofilm structure in the USMB combined with the CLP group, confirming that this combination has the greatest anti-biofilm effects. CONCLUSION: In this research, we successfully prepared USMBs and CLPs that have a more significant antibacterial effect on biofilm-forming AB than polymyxin B alone. Experiments in vitro indicate that the synergistic antibacterial effect of combining USMBs with CLPs containing as little as 2 µg/mL of polymyxin B is sufficient to almost eliminate drug-resistant biofilm-producing AB.

Effectiveness of an exercise support program in reducing the severity of postnatal depression in Taiwanese women.

BACKGROUND: Depression during the perinatal period should be identified as early as possible to avoid negative effects on the new family. The purpose of this study was to examine the effectiveness of an exercise support program on reducing psychological morbidity after childbirth. METHODS: A controlled trial was conducted in a regional hospital in Taipei, Taiwan. Eighty primiparas with an Edinburgh Postnatal Depression Scale (EPDS) score above 10 at 4 weeks postpartum agreed to participate. They were allocated alternately to an intervention (to receive exercise support) and control group (to receive standard care) at 6 weeks postpartum. The exercise support consisted of 1 hour per week at the hospital and two sessions at home for 3 months. Sixty-three primiparas finished the exercise support program. The main outcome measure was the EPDS score at 5 months postpartum. RESULTS: Women who received the exercise support program were less likely to have high depression scores after childbirth when compared with the control group. CONCLUSIONS: The exercise support program given to postpartum women appeared to benefit their psychological well-being. This promising finding should be tested in a well-designed randomized controlled trial.

Targeted photothermal ablation of pathogenic bacterium, Staphylococcus aureus, with nanoscale reduced graphene oxide.

Nowadays, bacterial infection is very common in the world. As a result of overusing antibiotics, several human pathogenic bacteria have become resistant to most of the clinically approved antibiotics. This has created an urgent need for the development of new methods to kill pathogenic bacteria. Here, we describe a novel method for the selective killing of pathogenic bacteria using antibody functionalized nanoscale reduced graphene oxide (NRGO). The antibody-NRGO complex exhibited little toxicity without near-infrared (NIR) irradiation. However, when irradiated with a NIR laser at a low power density (400 mW cm-2), the antibody-NRGO complex exhibited excellent photothermal properties and killed captured pathogenic bacteria specifically.

Dye-enhanced graphene oxide for photothermal therapy and photoacoustic imaging.

Graphene oxide (GO) has many exciting advantages such as easy preparation, low toxicity, good solubility and stability in aqueous solution. However, GO itself has a low near-infrared (NIR) absorption, and thus is not suitable for photothermal therapy and photoacoustic imaging. To overcome this limitation, a novel dye-enhanced GO is prepared utilizing the π-π stacking interactions between GO and indocyanine green (ICG). The ICG-GO complex has a high optical absorbance in the NIR region and exhibits excellent photothermal properties under NIR irradiation. In order to improve the cancer-targeting activity, GO was modified with folic acid (FA). In vitro experiments showed that the ICG-GO-FA nanocomposite could be used for targeted photothermal cancer cell destruction. Moreover, the application of the ICG-GO-FA nanocomposite for photoacoustic imaging was also demonstrated.

Effectiveness of a discharge education program in reducing the severity of postpartum depression: a randomized controlled evaluation study.

OBJECTIVE: The effectiveness of a hospital discharge education program including information on postnatal depression was evaluated to reduce psychological morbidity after childbirth. METHODS: A randomized controlled trial (RCT) was conducted in a regional hospital in Taipei. Two hundred first-time mothers agreed to take part and were randomly allocated to an intervention group (n=100) or control group (n=100). The intervention group received discharge education on postnatal depression provided by postpartum ward nurses. The control group received general postpartum education. The main outcome measure was the Edinburgh Postnatal Depression Scale (EPDS) administered by postal questionnaire at six weeks and three months after delivery. RESULTS: Women who received discharge education intervention on postnatal depression were less likely to have high depression scores when compared to the control group at three months postpartum. CONCLUSION: A discharge educational intervention including postnatal depression information given to women during the postpartum stay benefits psychological well-being. PRACTICE IMPLICATIONS: A postpartum discharge education program including information on postnatal depression should be integrated into postpartum discharge care in general practice.

Effectiveness of informational support in reducing the severity of postnatal depression in Taiwan.

AIM: The aim of the study was to investigate the effectiveness of informational support in reducing the Edinburgh Postnatal Depression Scale (EPDS) scores in Taiwan. METHODS: Five hundred Taiwanese women were screened during the fourth week after giving birth and those with a score of over 10 on the EPDS were considered to be at risk of postnatal depression. Seventy postpartum women were randomly allocated to the experimental or control group. Only those in the experimental group received informational support about postnatal depression during the sixth week postpartum. Two groups were assessed by the EPDS at 3 months postpartum to explore their depressive status. RESULTS: Taiwanese women who received informational support about postnatal depression 6 weeks after giving birth experienced lower EPDS scores at 3 months postpartum than those who did not receive this information. CONCLUSIONS: The findings suggest that informational support about postnatal depression given to women in the postnatal period may contribute to psychological well-being.