Temporal and Spatial Signatures of Scylla paramamosain Transcriptome Reveal Mechanistic Insights into Endogenous Ovarian Maturation under Risk of Starvation.

Variability in food availability leads to condition-dependent investments in reproduction. This study is aimed at understanding the metabolic response and regulatory mechanism of female Scylla paramamosain in response to starvation in a temporal- and tissue-specific manner. The mud crabs were starved for 7 (control), 14, 28, and 40 days for histological and biochemical analysis in the hepatopancreas, ovary, and serum, as well as for RNA sequencing on the hepatopancreas and ovary. We further highlighted candidate gene modules highly linked to physiological traits. Collectively, our observations suggested that starvation triggered endogenous ovarian maturation at the expense of hepatopancreas mass, with both metabolic adjustments to optimize energy and fatty acid supply from hepatopancreas to ovary in the early phase, followed by the activation of autophagy-related pathways in both organs over prolonged starvation. These specific adaptive responses might be considered efficient strategies to stimulate ovarian maturation of Scylla paramamosain under fasting stress, which improves the nutritional value of female mud crabs and other economically important crustaceans.

Electrically-driven chiroptical switches based on axially dissymmetric 1,1'-binaphthyl and electrochromic viologens: synthesis and optical properties.

A novel redox type of chiral molecular switch based on axially dissymmetric 1,1'-binaphthyl and electrochromic 4,4'-bipyridinium exhibits drastic changes in absorption and circular dichroism spectra upon electrochemical redox reaction and is fully characterized for the electrically driven chiroptical switching properties.

The changes of oxidative stress and human 8-hydroxyguanine glycosylase1 gene expression in depressive patients with acute leukemia.

The results of several recent studies indicated that free radicals are involved in the biochemical mechanisms that underlie neuropsychiatric disorders. In the present study, we evaluated changes in oxidative stress and human 8-hydroxyguanine glycosylase1 gene (hOGG1) expression in depressive patients with acute leukemia. Ninety two cases were assessed using the Zung self-rating depression scale (SDS) and multiple-item questionnaires. We measured total antioxidant capacity (T-AOC) and the concentrations of reactive oxygen species (ROS), superoxide dismutase (SOD), malondialdehyde (MDA) and nitric oxide (NO) during a pre-treatment period. The steady-state expression of hOGG1 mRNA transcripts was monitored. The incidence of depression was 47.83%. There was a significant decrease in serum T-AOC and SOD concentrations in depressive patients compared to the control subjects, whereas the opposite was the case for serum concentrations of ROS, NO and MDA. Real-time polymerase chain reaction (PCR) revealed that hOGG1 mRNA expression was greater in depressive patients than in the controls. Person correlation analysis revealed that depression was correlated positively with sex, the course of the disease and hOGG1 mRNA expression; depression was correlated negatively with T-AOC. Based on these results, we conclude that the antioxidant system is impaired in leukemic patients with affective disorders. Therefore, oxidative stress may play an important role in the pathophysiology of depression.

Self-assembly of well-defined polyacrylamide-polystyrene copolymer on fibrillar clays via ultrasonic-assisted surface-initiated atom transfer radical polymerization.

Well-defined polyacrylamide-polystyrene copolymers were grafted from the fibrillar clay, attapulgite, by a four-step self-assembly process: (i) the gamma-aminopropyltriethoxyl silane was self-assembled onto the surfaces of the attapulgite; (ii) the surface amino groups were amidated with bromoacetylbromide; (iii) the bromo-acetamide modified attapulgite was used as macro-initiator for the surface-initiated atom transfer radical polymerization of styrene with the catalyst of the complex of 1,10-phenanthroline and Cu(I)Br; (iv) the polystyrene grafted attapulgite was then used as macroinitiator for the polymerization of acrylamide. The two steps of the surface-initiated atom transfer radical polymerizations were all conducted under ultrasonic irradiation at room temperature. The product, polyacrylamide-polystyrene copolymers grafted attapulgite, had been characterized with elemental analysis, Fourier transform infrared spectroscopy, Thermogravimetric analysis (TGA), X-ray photoelectron spectroscopy, X-ray diffractometry, and transmission electron microscopy.

Preparation of poly(propyleneimine) dendrimer immobilized silica gel and its application as novel microcolumn packing for the on-line FI preconcentration and separation of platinum.

A G4.0 poly(propyleneimine) dendrimer immobilized silica gel (PPID-SG) was prepared with a divergent approach from gamma-aminopropyl silica gel (APSG) by repeating the reactions: 1) cyanoethylation of -NH2 and 2) reduction of -CN. Then it was successfully applied as the microcolumn packing for the on-line flow-injection (FI) preconcentration and separation and flame atomic absorption spectrometry (FAAS) determination of Pt. A limit of detection (LOD) of 0.014 microg/mL was obtained when 0.5 microg/mL Pt in chloride acid of PH = 3 was preconcentrated with a sample flow rate of 4.6 mL/min for 60s and the relative standard deviation (RSD) was 2.65%. Coexisting metal ions with concentration of 5.0 mg/mL and anion ions of 20.0 mg/ml have no interference in the determination of Pt. The proposed method was successfully applied to the determination of Pt in nickel alloy and anode slime samples.

Surface-initiated ATRP of HEA from nanocrystal alpha-Fe2O3 under ultrasonic irradiation.

Core/shell poly(beta-hydroethyl acrylate) (PHEA) encapsulated nanocrystal alpha-Fe2O3 nanospheres (Fe2O3@PHEA) were successfully prepared by the surface-initiated atom transfer radical polymerization (SI-ATRP) of beta-hydroethyl acrylate (HEA), a functional monomer, from the surfaces of the nanocrystal Fe2O3 modified with bromo-acetamide groups with the catalysts of 1,10-phenanthroline and Cu(I)Br under ultrasonic irradiation at room temperature in water. The products, Fe2O3@PHEA, were characterized by elemental analysis (EA), FT-IR, XRD, XPS and TEM. The percentage of grafting (PG%) of 38.95% and the conversion of HEA (C%) of 14.29% at room temperature for 6 h with ultrasonic irradiation were higher than the 22.41% and 8.22%, respectively, found for samples prepared by electromagnetic stirring. This demonstrated that the ultrasonic irradiation improves the SI-ATRP of HEA.

Preparation and characterization of core/shell SiO(x)/PAM nanospheres with 'graft from' method.

The core/shell SiO(2) encapsulated with polyacrylamide (SiO(x)/PAM) nanospheres were successfully prepared by the radical copolymerization of acrylamide (AM) and a macromonomer, methacryloxypropyl SiO(x) (MP-SiO(x)) nanoparticles, initiated with AIBN via a facile precipitation polymerization method in ethanol. The percentage of encapsulating (PE%) and the conversion of the AM (C%) of 327.5% and 93%, respectively, were achieved after a polymerizing time of 3 h. The formation mechanism of the core/shell SiO(x)/PAM nanospheres was explained. The nanospheres were characterized by elemental analysis (EA), Fourier transform infrared (FTIR), X-ray photoelectron spectrometer (XPS) and transmission electron microscope (TEM).

Interference-free determination of trace levels of gold and palladium in geological and metallurgical samples by flame atomic absorption spectrometry coupled with a flow injection on-line microcolumn preconcentration and separation system.

A simple and highly selective method was developed for the routine determination of trace or ultratrace amounts of gold and palladium in geological and metallurgical samples. The method uses flow injection on-line preconcentration and separation with determination by flame atomic absorption spectrometry. Au and Pd in the sample are adsorbed on a 2-mercaptopyrimidine chemically modified silica gel (MPMSG) packed microcolumn in a 0.50M HCl medium and then eluted with 0.5 or 1.0% thiourea solution. The eluates are introduced into the flame atomic absorption spectrometer directly. With the use of a 0.85 mL microcolumn (about 0.14 g MPMSG packed), the present system tolerated concentrations of common base metal ions up to 25.0 mg/mL and concentrations of anions up to 100.0 mg/mL when Au(III) at 0.100 microg/mL and Pd(II) at 0.200 microg/mL were preconcentrated for 60 s with a sample flow rate of 5.0 mL/min. The limits of detection were 3.1 ng/mL for Au(III) and 6.1 ng/mL for Pd(II) with relative standard deviations of < or = 2.5%. The analytical results obtained by the proposed method for geological and metallurgical samples were in good agreement with the certified values.

On-line separation and preconcentration of silver ion on amidino-thiourea immobilized glass beads packing in flow injection analysis with atomic absorption spectrometric detection.

Amidino-thiourea immobilized glass beads (AGB I) were prepared and used as the microcolumn packing for the flow injection (FI) on-line separation and preconcentration of Ag(I) coupled with atomic absorption spectrometry (AAS) determination. Base metal ions and anions with a concentration of 2.0 mg mL(-1) had no interference with the determination of Ag(I). The limit of detection (LOD) of Ag(I) for a preconcentration time of 60 s with a sampling flow rate of 5.0 mL min(-1) for 40.0 ng mL(-1) of Ag(I) were 0.50 ng mL(-1) with the peak-height absorbance mode and 1.26 ng mL(-1) with the peak-area absorbance mode, respectively. The relative standard deviations (RSD) of 7 replicate determinations were 0.9% and 0.7% for the peak-height absorbance (H) and the peak-area absorbance (A), respectively. The method was successfully applied to the determination of Ag(I) in ore samples.