Search

Effects of different nitrogen (N) compounds and concentrations on the growth of the three different phytoplankton taxa, Skeletonema costatum (Bacillariophyceae), Prorocentrum micans (Dinophyceae), and Chattonella marina (Raphidophyceae), were investigated. The Monod equation was applied to examine effects of N concentrations on the growth of algal cells. Results showed that nitrate (NO3-N) and urea served as good N sources for the three phytoplankton taxa. S. costatum grew well on all of the seven N sources. C. marina can effectively use the two amino acids, glycine (Gly) and serine (Ser), however cannot utilize alanine (Ala), threonine (Thr), and asparaginic acid (Asp). P. micans cannot grow in five amino acid substrates. All of the three phytoplankton taxa grew well under different proportions of urea-N, and C. marina grew significantly better in medium with both NO3- and urea-N. The values of maximum growth rate (µmax) and half-saturation nutrient concentration (KS) for NO3-N were 0.71 divisions d−1 and 53.55 µmol L−1 for S. costatum, 0.67 divisions d−1 and 23.31 µmol L−1 for P. micans, and 0.23 divisions d−1 and 17.57 µmol L−1 for C. marina, respectively. The results suggested that S. costatum had a high N demand for growth, and was capable of using wide ranges of N compounds. The strategy of N utilization for S. costatum may make this species an advantage in N-enriched sea areas especially the dissolved organic nitrogen (DON) rich coastal waters, which might be the reason why S. costatum widely distributes in the cosmopolitan coastal and estuarine sea areas.

In this work, ruthenium(II)-catalyzed C-C/C-N annulation of 2-arylquinazolinones with vinylene carbonate is reported to synthesize fused quinazolinones. This catalytic system tolerates a wide range of substrates with excellent functional-group compatibility. In this transformation, the vinylene carbonate acts as an ethynol surrogate without any external oxidant involved. Furthermore, preliminary mechanistic studies were conducted, and a plausible catalytic cycle was also proposed.

Three fractions of alkaline phosphatase activity (APA), including phytoplankton APA (phyto-APA), bacterial APA (bact-APA), and free-APA, were examined in the sea surface microlayer (SML) and the subsurface water (SSW) from Daya Bay, Guishan Island, and Guanghai Bay of southern China. Relationships between APA and environmental parameters were analyzed. The growth of phytoplankton was significantly limited by dissolved inorganic phosphorus (DIP) in the three sea areas, especially in Daya Bay. Total-APA ranged between 1.41 and 35.26 nmol/L/hr, and the highest value was found in Daya Bay. The increased APA in Daya Bay was the result of the increase of phytoplankton biomass and the response of phytoplankton to P limitation. Phyto-APA was the main contributor in Daya Bay, while phyto- and free-APA co-dominated in Guishan Island and Guanghai Bay. Bact-, phyto-, and total-APA showed a significant inverse power function relationship with DIP, and 0.2 μmol/L was the threshold for DIP on particulates and total-APA. Pearson correlation analysis suggested that DIP limitation together with high N levels enhanced APA. High water temperature and freshwater input accelerated APA as well. Principal component analysis clearly separated samples from the three sea areas, as well as from the SML and the SSW, which indicated the differences in environmental parameters and APA levels. Our results highlight the influence of phosphorus limitation and environmental parameters on APA.

Purpose. To assess the preventive effects of acupuncture at back-shu and front-mu acupoints on rats with restraint water-immersion stress (RWIS)-induced gastric ulcer. Methods. Thirty-six rats were randomly divided into four groups for 10 days of treatment as follows: the normal group received no treatment; the model group received RWIS-induced gastric ulcer; the omeprazole group was administered omeprazole orally every 2 days; and the electroacupuncture group received electroacupuncture at the RN12 and BL21 acupoints every 2 days. After 10 days of treatment, except for the normal group, all rats were induced with gastric ulcer by RWIS for 3 h. The ulcer index (UI), ulcer inhibition rate, and histopathological score were calculated. We determined the levels of tumor necrosis factor (TNF)-α and interleukin (IL)-6 in serum, and the activities of myeloperoxidase (MPO), malondialdehyde (MDA), superoxide dismutase (SOD), nitric oxide (NO), and glutathione peroxidase (GSH-Px) in serum and gastric tissues. Protein expression of MyD88, nuclear factor (NF)-κB (p65), and toll-like receptor (TLR) 4 was quantified in gastric tissues. Results. The electroacupuncture and omeprazole groups were equivalent in terms of UI, ulcer inhibition rate, and histopathological score. The serum levels of TNF-α and IL-6 were significantly lower in the electroacupuncture group compared with the omeprazole group ( P

Background: Hepatic fibrosis is an inflammatory liver disease, and there is no effective therapy at present. Astilbin is a bioactive ingredient found in many medicinal and food plants, with antioxidative, anti-inflammatory, and antitumor properties. Objectives: This study aimed to investigate the protective effect and related molecular mechanism of astilbin against carbon tetrachloride (CCl4)-induced liver fibrosis in rats. Methods: Liver fibrosis was induced by injection of CCl4 in male Sprague-Dawley rats, and those rats were then treated with astilbin at different concentrations. Pathological changes, collagen production, inflammatory cytokine, and oxidative stress were evaluated to evaluate the effects of astilbin on CCl4-induced hepatic fibrosis. Real-time PCR and western blot were performed to detect the mRNA and protein expression of indicated genes. Results: We discovered that CCl4 caused significant fibrosis damage in rat liver, and astilbin dose-dependently improved the liver functions and fibrosis degree. Astilbin treatment significantly decreased collagen production, inflammatory response, and oxidative stress in vivo. Mechanically, administration of astilbin obviously elevated the hepatic levels of Nrf2 and its downstream components, including NAD(P)H:quinone oxidoreductase 1 (Nqo1), heme oxygenase (HO-1), glutamate-cysteine ligase catalytic subunit, and glutamate cysteine ligase modifier. Conclusions: Taken together, these findings demonstrate that astilbin could protect against CCL4 induced-liver fibrosis in rats.

In this work the ability of pure surfactant Sodium Dodecyl Sulfate (SDS), Cetyltrimethyl Ammonium Bromide (CTAB) and their mixed surfactants for graphene dispersion in aqueous solution was investigated. The uniform and stable dispersion solution was obtained for graphene with the mixtures of SDS and CTAB at lower concentration as compared to the pure one. The SDS-based surfactants exhibited better dispersion as compared to CTAB-based surfactants due to smaller-sized graphene as was investigated via Zeta potential measurements. Zeta potential was utilized to characterize the colloidal stability of surface charges within the mixtures. The mixed surfactants utilized in the present study showed a better ability to disperse graphene and its derivatives and hence are well suited for practical applications.

The sea surface microlayer (SML), which is the uppermost layer of the water column between the ocean and atmosphere, has unique physicochemical and biological properties and plays a significant role in biogeochemical processes. Water samples were collected from the SML of Daya Bay in Southern China between June and August of 2013. Algal growth potential (AGP) tests were conducted following the addition of different concentrations of inorganic nitrogen (N), phosphorus (P) and silicate (Si) under laboratory conditions. The purpose of this study was to evaluate the effects of nutrient enrichment on phytoplankton in the SML. Chl a increased significantly after nutrient addition, and the biggest increase occurred in test groups with the addition of three nutrient elements. Nutrient concentrations decreased sharply, along with the growth of phytoplankton. Photoprotective carotenoids (PPCs) generally decreased after nutrient addition, while photosynthetic carotenoids (PSCs) became prominent after nutrient addition. Phytopigments were dominated by zeaxanthin (Zea), which contributed to 36.7%–79.4% of the total accessory pigments (TAcc). The next most abundant pigment was fucoxanthin (Fuco), with proportions of 15.2%–39.3%. Percentages of Zea decreased significantly after nutrient addition, and those of Fuco increased accordingly. The results suggest that the phytoplankton in the SML in Daya Bay is dominated by cyanobacteria followed by diatoms but that nutrient addition (i.e. eutrophication) might lead to a switch in dominance.

Pressure overload has an important role in heart failure, inducing excessive autophagy in cardiac myocytes that is considered to be pathogenic. Resveratrol has been reported to improve cardiac dysfunction induced by pressure overload, but it has been unclear whether resveratrol ameliorates cardiac dysfunction by regulating autophagy. In this study, heart failure was induced in rats by constriction of the abdominal aorta. Four weeks after surgery, the rats with heart failure were randomized to treatment with resveratrol (8 mg · kg(-1) · d(-1) by intraperitoneal injection) for 28 days or to intraperitoneal injection of the vehicle (propylene glycol) alone. Echocardiography was performed to assess cardiac function. Expression of brain natriuretic peptide messenger RNA in the left ventricle was detected by real-time polymerase chain reaction, whereas expression of proteins associated with autophagy (beclin-1 and lamp-1) was detected by western blotting and immunohistochemistry. Furthermore, autophagic vacuoles were detected in the heart by transmission electron microscopy, and the myocardial ATP content was measured by the bioluminescence method. Treatment with resveratrol significantly improved cardiac dysfunction and reduced brain natriuretic peptide expression in rats with heart failure. Resveratrol down-regulated beclin-1 and lamp-1 expression and also inhibited the formation of autophagic vacuoles in failing hearts. Furthermore, resveratrol restored the myocardial ATP level and reduced phosphorylation of AMP-activated protein kinase at Thr172. These results suggest that resveratrol may inhibit autophagy through inactivation of AMP-activated protein kinase and restoration of ATP in heart failure induced by pressure overload. Accordingly, resveratrol may be beneficial for patients with hypertensive heart disease.

Backgrounds and aims MicroRNAs (miRNAs) have been reported to be involved in degenerative disorders including Parkinson’s disease (PD). α-synuclein expression is strong associated with the pathogenesis of PD. In the present study, we investigated whether the regulation of α-synuclein expression by miR-214 is the potential mechanism underlying the neuroprotective effect of Resveratrol. Methods The PD mouse model was established with the injection of MPTP (1-Methyl-4-phenyl-1,2,3,6-tetrahydropyridine) and the human neuroblastoma cell line, SH-SY5Y, was administrated with MPP+. Results The midbrain of PD mice and MPP+ treated SH-SY5Y cells had the lower expression levels of miR-214 and higher mRNA and protein expression of α-synuclein, which were reversed by Resveratrol administration. MiR-214 mimic down-regulated expression of α-synuclein and its 3′-UTR activity, while the levels were up-regulated by miR-214 inhibitor. In addition, the cell viability, elevated by Resveratrol, was also decreased by miR-214 inhibitor or overexpressed α-synuclein. In vivo , miR-214 inhibitor down-regulated TH+ cells of ipsilateral and up-regulated α-synuclein expression compared with the group treated with Resveratrol. Conclusion The loss of miR-214 in PD resulted in the increase of α-synuclein expression, which was the potential mechanism underlying the neuroprotective effects of Resveratrol.

We have prepared N1-ethyl-5′-bromo-7-azaindirubin-3′-oxime due to its potential for being a pharmaceutical. Infrared and Raman spectra have been recorded and vibrational assignments have been suggested based mainly on our previous vibrational investigation of N1-isopropyl-5′-chloro-7-azaindirubin-3′-oxime and on group characteristic frequencies. Temperature variation study has revealed the presence of conformers due to the internal rotation of ethyl group. IR spectra collected for N1-ethyl-7-azaindirubin-3′-oxime have shown rather similar spectral features with that of N1-ethyl-5′-bromo-7-azaindirubin-3′-oxime. IR spectra of these compounds have revealed the association through hydrogen bonding in the solid state. IR spectra recorded for these samples after annealing at high temperatures indicated the thermal conversion temperature to be lowered than 270 °C. Results from thermal analyses have determined the beginning decomposition temperatures to be 250 °C and the decomposition enthalpies to be 94 kJ/mol for both N1-ethyl-5′-bromo-7-azaindirubin-3′-oxime and N1-ethyl-7-azaindirubin-3′-oxime.

The potential adverse effects of e-waste recycling activity on environment are getting increasing concern. In this work, a model alga, Pseudokirchneriella subcapitata, was employed to assess the toxic effects of the leachates of paddy soils and river sediments collected from e-waste dismantling sites. Chemical analysis of the paddy soils and river sediments and their leachates were carried out and the growth rate, chlorophyll a fluorescence and anti-oxidative systems of the alga were measured. Results showed that two leachates decreased the amount of PSII active reaction centers and affected photosynthesis performance, interfered with chlorophyll synthesis and inhibited algal growth. Some chemical pollutants in the sediments and soils such as polybrominated diphenyl ethers (PBDEs) and metals derived from e-waste recycling activity may impose oxidative stress on algae and affect the activity of anti-oxidative enzymes such as GST, SOD, CAT and APX. The leachates of both river sediments and paddy soils are potentially toxic to the primary producers, P. subcapitata and the leachate from sediments was more deleterious than that from soils.

Effects of heating, ultraviolet (UV), ultrasound (US), hydrogen peroxide (H2O2) and freshwater, and the combined treatments on inactivation of cysts of Scrippsiella trochoidea and cysts in sediment suspension were studied. Heating was the most efficient way to inactivate cyst germination, and cysts were completely inactivated at 38 °C for 5 h. UV, US, and freshwater efficiently inhibited but could not completely inactivate cyst germination. Effects of heating, UV, and US on cyst germination decreased for cysts in sediment, and germination rates increased by 6.7–48% compared to the same treatment for cysts without sediment. H2O2 significantly inhibited cyst germination, but complete inactivation occurred at high concentration for long duration (100 mg/L, 6d). The combined treatments were more effective, especially the combinations of heating and UV. The results suggested that heating might be a feasible way for ballast water treatment especially after combined with filtration and UV.

Plant growth and crop production depend to a large extent on soil N supplying capacity (SNSC): The higher the SNSC, the higher the dependence of crops on soil and the lower the N fertilizer recovery. Of the SNSC, soil organic N (ON) played a key role in supplying N nutrient to crop production and still does in many subsistence and low-input farming systems. In this paper, soil ON contents, types, chemical components and its contribution to plant production are reviewed up to date in details, the characteristics of ON in dryland soils discussed together with its chemical components, and the mineralization and availability to plants of some important chemical components are emphasized at the last part for practical considerations.

Surface sediments collected from Zhelin Bay, the largest mariculture base of eastern Guangdong Province, were analyzed for total metal concentrations and chemical speciation. The results demonstrated that the average total concentration (mg/kg) ranges were 36.7-65.8 (Pb), 53.8-98.8 (Cr), 39.0-87.1 (Ni), 50.9-144.5 (Cu), and 175.0-251.2 (Zn), which were clearly higher with respect to their corresponding benchmark values. The predominant speciation of Pb was reducible and comprised a residual fraction, whereas a major portion (57.6-95.4%) of Cr, Ni, Cu, and Zn was strongly associated with the residual fractions. Taking as a whole, surface sediments of Zhelin Bay had a 21% probability of toxicity based on the mean effects range-median quotient.

The aim of the present study was to prepare and evaluate a paclitaxel nanocrystal-based formulation stabilized by serum protein transferrin in a non-covalent manner. The pure paclitaxel nanocrystals were first prepared using an antisolvent precipitation method augmented by sonication. The serum protein transferrin was selected for use after evaluating the stabilizing effect of several serum proteins including albumin and immunoglobulin G. The formulation contained approximately 55-60% drug and was stable for at least 3months at 4°C. In vivo antitumor efficacy studies using mice inoculated with KB cells demonstrate significantly higher tumor inhibition rate of 45.1% for paclitaxel-transferrin formulation compared to 28.8% for paclitaxel nanosuspension treatment alone. Interestingly, the Taxol(®) formulation showed higher antitumor activity than the paclitaxel-transferrin formulation, achieving a 93.3% tumor inhibition rate 12days post initial dosing. However, the paclitaxel-transferrin formulation showed a lower level of toxicity, which is indicated by a steady increase in body weight of mice over the treatment period. In comparison, treatment with Taxol(®) resulted in toxicity issues as body weight decreased. These results suggest the potential benefit of using a serum protein in a non-covalent manner in conjunction with paclitaxel nanocrystals as a promising drug delivery model for anticancer therapy.

Environmental parameters and phytoplankton communities in the sea surface microlayer (SML), subsurface water (SSW) and sub-bottom water (SBW) were surveyed in Daya Bay, South China Sea, from May 2007 to April 2008. A total of 142 taxa were identified, including 88 diatoms and 32 dinoflagellates. Diatoms represented 88.6%, 91.5% and 48.4% of total phytoplankton abundance in the SML, SSW and SBW, respectively. The phytoneuston community differed markedly from the phytoplankton due to a major increase in the proportion of cyanobacteria, comprising 42.1% of the total phytoneuston based on the microscopic observation. Cyanobacteria were highly enriched in the SML, with an average enrichment factor (EF) of 4.42 and an enrichment frequency of 100%. Diatoms, dinoflagellates, overall phytoplankton and chlorophyll a were depleted in the SML samples, yet there might be some small sized phytoneuston especially those of flagellates that were not accurately measured under the microscopic examination. All nutrients were enriched in the SML, especially phosphorus. In contrast with the negative correlations found between nutrients and total phytoplankton, the cyanobacteria showed significantly positive relationships with nutrients and negative relationships with total phytoplankton and diatoms. The results of the study suggest that the phytoneuston in Daya Bay is a unique community jointly dominated by cyanobacteria and diatoms. In contrast, diatoms alone dominate the phytoplankton community in the bulk water. These changes in the phytoneuston community may be indicators of the particular environmental changes in Daya Bay, such as increasing water temperature, global warming, high nutrient loads and increased dissolved organic nutrients.

For centuries Danggui Longhui Wan has been used to treat chronic ailments, such as myelocytic leukemia. In the 1960s, the active ingredient in Danggui Longhui Wan was isolated and identified as indirubin. Indirubin has shown potent inhibition of cyclin-dependent kinase through binding to the ATP-binding site. However, indirubin shows poor solubility and low absorption, hence many derivatives have been developed to enhance these properties. One such derivative is 5′-chloro-1-isopropyl-7-azaindirubin-3′-oxime (CIADO), investigated in the current work. Infrared and Raman spectra were collected and compared with predicted spectra using density functional theory. Based on theoretical calculations, the most stable form of CIADO isomer is found to be cis (Z) and trans (E) with respect to the ring system linkage and the 3′-oxime functional group respectively. Also observed were two distinct internal rotational minima for the 1-isoprooyl group separated by a large energy barrier. The presence of two distinct isopropyl conformations observed in our calculations was confirmed with temperature-dependent IR experiments. Assignment of experimental vibrational modes was carried out based on functional group displacement observed in the calculations.

Objective Numerous long non-coding RNAs (lncRNA) have been identified in neurodegenerative disorders including Parkinson’s disease (PD). Emerging evidence demonstrates that β-asarone functions as neuroprotective effects in both in vitro and in vivo models. However, the role of β-asarone and its potential mechanism in PD remain not completely clear. Methods MPTP-induced PD mouse model and SH-SY5Y cells subjected to MPP+ as its in vitro model were used to evaluate the effects of β-asarone on PD. LncRNA MALAT1 and α-synuclein expression were determined by real-time PCR and western blot methods. Results β-Asarone significantly increased the TH+ cells number and decreased the expression levels of MALAT1 and α-synuclein in midbrain tissue of PD mice. RNA pull-down and immunoprecipitation assays confirmed that MALAT1 associated with α-synuclein, leading to the increased stability of α-synuclein and its expression in SH-SY5Y cells. β-asarone elevated the viability of cells exposed to MPP+. Either overexpressed MALAT1 or α-synuclein could canceled the protective effect of β-asarone on cell viability. In PD mice, pcDNA-MALAT1 also decreased the TH+ cells number and increased the α-synuclein expression in PD mice with treatment of β-asarone. Conclusion β-Asarone functions as a neuroprotective effect in both in vivo and in vitro models of PD via regulating MALAT1 and α-synuclein expression.

Growing concerns surround the mid Guangdong coasts, one of China’s fastest and developing economical regions. To study the environmental impacts of economic and industrial development, we measured ten metallic elements (Hg, Pb, Cu, Zn, Fe, Al, Ni, Sr, Li, and Co) in surface sediments from nineteen stations in three bays. All these metals showed concentrations substantially higher than their background values, suggesting possible anthropogenic pollution. Highest metal levels were close to the nuclear power plants likely as a result of nuclear waste discharges. Results revealed that Hg, Pb, and Sr largely originated from human activities, while Cu, Ni, Co, Al, and Fe mainly from natural rock weathering. Two types of anthropogenic sources were identified through a principal component analysis, one from shipping industry, port transport service and nuclear power plants, and the other from municipal sewage and coal power plant.

The utilization of nine dissolved organic phosphorus (DOP) compounds by five bloom-causing phytoplankton species was studied under batch culture conditions. The DOP compounds included were adenosine 5-triphosphate (ATP), adenosine 5-monophosphate (AMP), cytidine 5-monophosphate (CMP), guanosine 5-monophosphate (GMP), uridine 5-monophosphate (UMP), glucose-6-phosphate (G6P), sodium glycerophosphate (GYP), 4-nitrophenyl phosphate (NPP), and triethyl phosphate (TEP), and the phytoplankton taxa were Skeletonema costatum, Prorocentrum micans, Alexandrium tamarense, Chattonella marina, and Heterosigma akashiwo. The four flagellate taxa, P. micans, A. tamarense, C. marina, and H. akashiwo, grew well under various DOP regimes. P. micans and C. marina were the most capable of using DOP compounds, sustaining better growth on a majority of nucleotides (ATP, AMP, CMP, GMP, and UMP) and phosphomonoesters (G6P and GYP) than in inorganic phosphorus (P) controls. A. tamarense and H. akashiwo showed equivalent growth in most organic and inorganic P cultures, while the diatom species, S. costatum, could only utilize AMP and GMP. Furthermore, A. tamarense and C. marina could endure N, P-depleted conditions. Among the nine DOP compounds tested, the nucleotide compounds had the highest nutritional value for algal cell growth, while TEP could not sustain growth as the sole source of P. These results suggest that enhanced DOP utilization and the endurance of nutrient-limitation by harmful flagellate taxa offer their competitive advantages, which may account for the frequent occurrence of their blooms in coastal waters.

The effects of three types of antibiotics (erythromycin, ciprofloxacin and sulfamethoxazole) on the photosynthesis of freshwater algae, Selenastrum capricornutum Printz, were investigated by determining the growth rate, chloroplast pigments content, seven main precursors (including delta-aminolevulinic acid, porphobilinogen, uroporphyrinogen III, coproporphyrinogen III, protoporphyrin IX, Mg-proporphyrin IX and protochlorophyllide), and photosynthetic rate during chlorophyll biosynthesis. The antibiotics significantly decreased the growth rate, chlorophyll content, and photosynthetic rate. Erythromycin induced a decreasing effect at a concentration of 0.06 mg/L, while ciprofloxacin and sulfamethoxazole achieved the same results at concentrations higher than 1.5 mg/L. Only erythromycin significantly inhibited chlorophyll biosynthesis, which indicated that it was considerably more toxic to S. capricornutum than ciprofloxacin and sulfamethoxazole, and may pose a high potential risk to aquatic ecosystems.

Background Accumulating evidence suggests that the occurrence of oxidative stress leads to melanocyte degeneration in vitiligo. Elevated level of dopamine (DA), an initiator of oxidative stress, reportedly is found in patients with vitiligo and induces melanocyte death in vitr o. DA-treated melanocytes have been used as a model to search for antioxidants for treating vitiligo. Objective We investigated the protective effects of apigenin against DA-induced apoptosis in melanocytes and the molecular mechanism underlying those effects. Methods Melanocytes with or without pretreatment with apigenin were exposed to DA. Then cell viabilities were measured by MTT assay. Cellular reactive oxygen species (ROS) levels and the percentage of apoptotic cells were detected by flow cytometry analysis. Activation of caspase 3, poly(ADP-ribose) polymerase (PARP) and oxidative stress-related signaling, including p38, c-Jun NH2-terminal kinase (JNK) and Akt, were assessed by Western blotting. Results Apigenin attenuated DA-induced apoptotic cell death, relieved ROS accumulation and activated caspase 3 and PARP, suggesting the protective effects of apigenin against DA-induced oxidative stress and apoptosis in melanocytes. Moreover, DA induced phosphorylation of p38, JNK and Akt, while inhibitors of p38, JNK and Akt significantly decreased DA-induced apoptosis. However, pretreatment with apigenin significantly inhibited DA-triggered activation of p38, JNK and Akt, suggesting the involvement of p38, JNK and Akt in the protective effects of apigenin against DA-induced cytotoxicity. Conclusion These results suggest that apigenin attenuates dopamine-induced apoptosis in melanocytes via oxidative stress-related p38, JNK and Akt signaling and therefore could be a potential agent in treating vitiligo.

The growth of three marine phytoplankton species Skeletonema costatum, Scrippsiella trochoidea and Chattonella marina and the response of the antioxidant defense system have been investigated on exposure to commercial cypermethrin for 96 h and 32 days in a co-culture system. Growth of the three species was generally comparable over 96 h with an inoculation of 1:3:6.5 (C. marina:S. trochoidea:S. costatum), with stimulation at 5 μg l(-1) and inhibition under higher concentrations (50, 100 μg l(-1)). However, when inoculating at ratios of 1:1:1 during a 32 day test, S. costatum became the most sensitive species and was significantly inhibited in all test groups under the dual stresses of cypermethrin and interspecies competition. The growth of C. marina was significantly inhibited at the concentrations higher than 5 μg l(-1), while the growth of S. trochoidea was significantly promoted at low concentrations. Superoxide dismutase (SOD) activities significantly increased during 6-12 h exposure periods in test treatments at low concentrations, and enhanced in the control as well due to interspecies competition. The lipid peroxidation product malondialdehyde was enhanced at high concentrations, but did not increase in control and low concentration cultures with high SOD activities, indicating that algal cells activated the antioxidant enzymes promptly to protect the cells from lipid membrane damage. Results from this study suggested that cypermethrin pollution in maricultural sea waters might lead to a shift in phytoplankton community structure from diatom to harmful dinoflagellate species, and thus potentially stimulatory for harmful algal blooms.

A series of novel 7′-azaindirubin ( 1a – g ) and 7-azaindirubin ( 2a , 2c , 2e and 2f ) derivatives were designed and synthesized. Their structures were characterized by 1 H NMR and MS spectroscopy as well as by elemental analysis. Their inhibitory properties against CDK2/cylinA were evaluated in vitro . In contrast to indirubin, some of the described azaindirubins emerged as potent inhibitors of CDK2/cylinA and compound 2b had more potent activity. Biological tests also showed that nitrogen atom at 7-position of azaindirubin was more beneficial to enhance the kinase inhibitory activity.

Novel chiral 1,3-aminophenols were efficiently synthesized by applying a Friedel–Crafts reaction and optical resolution. The catalytic activity of the aminophenols was studied for the addition of diethylzinc to benzaldehyde. The results showed that ( S )- 5a with bulky tert -butyl groups on the stereogenic carbon atom and 4,6-positions of phenol favored higher enantioselectivity (94% ee). The same ligand was also used with other aldehydes, to give optically active alcohols in good chemical yields and ee values (up to 99%).

Metals and biogenic elements were analyzed from surface sediments and a 100cm core collected from Jiaozhou Bay in July 2009, to determine how the environment has changed over the past 90years due to increasing anthropogenic influences in this region. High concentrations of biogenic silica (BSi) represented the dominance of diatoms in the bay. Most metals were lower than the marine sediment quality guidelines; however, Hg, Zn, and Mn were at polluted levels. The vertical profiles of biogenic elements and metals in the sediment core suggest that the most significant environmental changes occurred since the 1990s, and three stages could be defined: (1) before 1950, characterized by low concentrations of biogenic elements and metals; (2) between 1950 and 1990, displaying an obvious increase of Hg and a slow increase of biogenic elements; (3) after 1990, reflected by a significant increase of total organic carbon (TOC), total nitrogen (TN), total phosphate (TP), and most metals, but a decrease of BSi. Correlation and principal component analyses indicated that most metals originated from lithogenic sources, industrial and domestic discharges as well as maricultural activities.

Transforming growth factors β (TGF-β) pathway has been proven to play important roles in oncogenesis and angiogenesis of gliomas. MiR-132 might be related to TGF-β signaling pathway and high miR-132 expression was reported to be a biomarker of poor prognosis in patients diagnosed with glioma. However, the expression regulation way involved in TGF-β pathway and clinical significance of miR-132 have not been investigated in glioma cells. Here we reported that the mRNA level of miR-132 and TGF-β concentration were both increased in patients with brain glioma. Correlation analysis revealed that TGF-β concentration was positively correlated with mRNA level of miR-132. In addition, the mRNA level of miR-132 was up-regulated by TGF-β in a concentration-dependent and time-dependent manner. Furthermore, we found that miR-132 was involved in modulation of the TGF-β signaling pathway and down-regulation of SMAD7 expression by directly targeting the SMAD7 3'-UTR. MiR-132 was negatively correlated with SMAD7 in patients with brain glioma. Taken together, our results suggest that miR-132 could be stimulated by TGF-β and might enhance the activation of TGF-β signaling through inhibiting SMAD7 expression in glioma cells. These findings contribute to a better understanding of the mechanism of the activation of TGF-β signaling by miR-132.

Homeobox (HOX) transcript antisense RNA (HOTAIR), as a long intergenic noncoding RNA (lincRNA), is known to be overexpressed in several cancers. However, the role of HOTAIR in Parkinson's disease (PD) remains unclear. A mouse model of PD was developed by intraperitoneal injection of MPTP (N-methyl-4-phenyl-1,2,3,6- tetrahydropyridine). The expression of HOTAIR and LRRK2 (leucine-rich repeat kinase 2) were detected in the PD mice and in Human neuroblastoma cell lines SH-SY5Y pretreated with MPP+ (N-methyl-4-phenylpyridinium). The effect of HOTAIR on the expression of LRRK2 was examined in SH-SY5Y cells through overexpressing HOTAIR. A MTT (3- (4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide) assay was performed to measure the cell viability of SH-SY5Y cells. si-HOTAIR (siRNA-HOTAIR) was utilized to investigate the effect of HOTAIR on the expression of LRRK2 in vivo. In this study, upregulation of HOTAIR and LRRK2 were found in the midbrain of PD mice induced by MPTP and in SH-SY5Y cells pretreated with MPP+. With the presence of HOTAIR overexpression in SH-SY5Y cells, the expression of LRRK2 was increased compared with that in the control. HOTAIR knockdown showed a protective effect on the cell viability of SH-SY5Y cells pretreated with MPP+, which was abrogated by overexpression of LRRK2. In mouse model of PD treated with si-HOTAIR, the expression of LRRK2 was decreased. In conclusion, high expression of HOTAIR promoted the onset of PD induced by MPTP. Moreover, the finding that HOTAIR promoted PD induced by MPTP through regulating LRRK2 expression could add our understanding of the molecular mechanisms in PD.

In this paper the microstructure evolution of AZ91HP magnesium alloy casts produced under different disturbing treatment conditions such as non-disturbing, argon blowing and mechanical stirring in semi-solid state after holding a short time was studied. The results show that the grains of AZ91HP alloy casts refined, the secondary dendritic arms grown and the dendrites tend to rosette shape with the decrease of holding temperature. External disturbance can accelerate the evolution process, and the spherical primary α phase formed easily under mechanical stirring treatment condition. The formation of non-dendritic structure is owing to ripening of the dendritic arms, refinement of the grains and movement of the primary formed solid phases. Disturbing treatments in semi-solid state induce more equilibrium solidification and decrease the amount of brittle β-Mg17Al12 phase. Blowing argon into the refined and modified magnesium alloy in semi-solid state can obtain homogeneous non-dendritic structure and the net shaped β phase distributed on α-Mg phase boundaries become fine and thin, this may be have a good effect on the mechanical properties of the magnesium alloy casts. Due to the low disturbing strength, argon blowing can maintain the metallurgy quality of the semi-solid slurry well, and also have high efficiency to make it. This technology need not new complex equipments and can be practiced in conventional casting conditions, so it may be used in industrialize manufacture.

In this paper, with a newly self-developed rotating barrel rheomoulding machine(RBRM), microstructures and mechanical properties of rheo-die casting A356 alloy were studied. In order to clearly show the characteristic of rheo-die casting, liquid die casting and semi-solid casting were done too. The experimental results showed that microstructures of rheo-die casting were composed of solid grains, which were finer and rounder, and had fewer pores. In the three technologies, integrated mechanical properties of semi-solid rheo-die casting were the best.

In the crystal structure of the title complex, [Cd(C2N3)2(C8H10N4)]n or [Cd(dca)2(bim)]n, where dca is dicyanamide and bim is 1,2-bis­(imidazol-1-yl)ethane, each CdII atom is in a distorted octa­hedral environment. Four N atoms from four dca ligands occupy the equatorial positions, and two N atoms from two bim ligands occupy the axial positions. Each CdII atom is situated at a center of symmetry, and a twofold axis runs through the mid-points of the bim exocyclic C—C bond and the Cd⋯Cd vector. The structure consists of chains in which neighboring CdII atoms are connected through one bim and two end-to-end dca bridges.

Magnesium alloys offer advantages of low density, high specific strength, machinability and availability. So it has been used more and more in many fields, such as automobile, communication etc. In this paper, grain refinement process and SiC nanoparticles reinforcement process are investigated for the purposes of increasing ultimate tensile strengthen and ductility of AM60B magnesium alloys. We find that after grain refinement process the ultimate tensile strength of AM60B alloys with permanent casting increase to 241MPa, which is about 27MPa higher than that of original alloys, and the elongation of it increases up to 20.1%, which is about 8.7% higher than that of original alloys. We added SiC nanoparticle into AM60B alloys in liquid state and found it could increase strength and ductility of alloys. By SiC nanoparticle reinforced process the ultimate tensile strength of magnesium alloys can increase up to 255MPa with the elongation of 19%.

The absolute configuration of endo-3-benzamidonorborn-5-ene-2-carboxylic acid was determined by X-ray single crystal analysis of the diastereomeric salt with cis-2-(benzylamino)cyclohexylmethanol. ...

To investigate the possible similarity of the proinsulin folding process with insulin-like growth factor I, two swap-like human proinsulin mutant proteins [A7,A11Ser]-HPI and [A11Ser,A12Cys]-HPI were prepared. Their in vitro refolding yields, oxidation of free thiol groups, circular dichroism spectra, antibody and receptor binding activities and sensitivity to trypsin digestion were studied and compared with both native HPI and [A6,A11Ser]-HPI. The results indicate that the shift mutation in the disulfide bond caused more conformational change and a greater decrease in biological activity than the deletion mutation on the proinsulin molecule. However, the shift of the intra-A chain disulfide bond had little effect on the refolding rate of the molecule. In vitro refolding yields of HPI analogues with shift or deletion mutations in the region of the [A6-A11,A7-B7] disulfide bonds were almost as high as that of wild type HPI suggesting that the region of the [A6-A11,A7-B7] disulfide bonds possesses some flexibility as is found in the corresponding region of insulin-like growth factor I.

Relaxin is a small 6 kD two-chain peptide member of the insulin superfamily that is principally produced in the corpus luteum of the ovary and which plays a key role in connective tissue remodeling during parturition. Like insulin, it is produced on the ribosome as preprohormone that undergoes oxidative folding and subsequent proteolytic processing to yield the mature insulin-like peptide. In contrast to the now considerable insight into insulin chain folding and oxidation, comparatively little is known about the folding pathway of relaxin. A series of synthetic pairwise serine substituted relaxin A-chain cysteine analogues was prepared, and their oxidation behavior was studied both on their own and in the presence of native relaxin B-chain. It was observed that native S-reduced A-chain oxidized rapidly to a bicyclic product, whereas individual formation of each of the intramolecular disulfide bonds between Cys11 and Cys24 and the native Cys10 and Cys15 was considerably slower. Curiously, the non-native, isomeric Cys11-Cys15 disulfide bond formed most rapidly, although circular dichroism spectroscopy analysis showed this product to be devoid of secondary structure. This suggested that it may in fact be an intermediate in the subsequent formation of the native Cys10-Cys15 intramolecular disulfide. Combination of the native A-chain with the B-chain proceeded rapidly as compared with the A-chain analogue that lacked the intramolecular disulfide bond suggesting that this latter element is required as a first step in the folding process. It is therefore probable that relaxin is generated from its constituent A- and B-chains in a stepwise organization manner similar to that of insulin chain combination and folding. Further studies showed that the efficiency of combination of A-chain to B-chain was not markedly influenced by reaction temperature and that a reasonable yield of relaxin could be obtained on combination of the preoxidized A-chain with the S-reduced B-chain.

The growth and alkaline phosphatase activity (APA) of two raphidophyceae species Chattonella marina and Heterosigma akashiwo were investigated in response to P-limitation and subsequent addition of dissolved inorganic phosphorus (DIP, NaH2PO4) and two dissolved organic phosphorus (DOP) compounds: guanosine 5-monophosphate (GMP) and triethyl phosphate (TEP). APA levels increased greatly after P-starvation as the decrease of the cellular phosphorus quotes (Qp). C. marina responded to P-limitation quickly and strongly, with 10-fold increase in APA within 24 hr after P-starvation. The larger difference between maximal and minimal QP values in C. marina indicated its high capacity in P storage. APA of H. akashiwo was maximally enlarged about 2.5 times at 48 hr of P-starvation. After the addition of nutrients, cell numbers of C. marina increased in all treatments including the P-free culture, demonstrating the higher endurance of C. marina to P-limitation. However, those of H. akashiwo increased only in DIP and GMP cultures. APA increased only after the addition of the monophosphate ester GMP. The results suggest that quick responses of C. marina to P-limitation, high capacity in P storage as well as endurance for P-depletion provide this species an ecological advantage in phytoplankton community competition under DIP-limited conditions.

A coupled heat and mass transfer model is developed for batch fluidized-bed drying of moist porous particles considering the temperature, moisture saturation and pressure distributions in the particle. The model equations are solved numerically based on physical properties of apple. The heat and mass transfer mechanisms in the fluidized-bed drying process are analyzed. The results show that capillary flow and vapor diffusion play different roles in moisture transfer in the particle during different drying periods. The internal heat transfer can greatly affect the drying process while the effect of gas pressure distribution is insignificant. Due to the coupled effects between gas and particles, the state of gas in the fluidized-bed changes substantially along the bed height and affects the heat and mass transfer in the particle significantly. A new parameter called bed area factor is derived and analyzed. It is important in determining the drying efficiency in the design and operation of fluidized-bed dryers. The effects of particle parameter and inlet gas conditions on heat and mass transfer in the fluidized-bed drying process are discussed through the analyses of drying characteristics.

A mathematical model of heat and mass transfer is developed for fluidized-bed drying with microwave heating. The numerical results show that the temperature is uniformly distributed within a particle and that the pressure distribution in the particle has a significant effect on microwave fluidized-bed drying. The electric field strength E is an important parameter affecting the magnitude and distribution of the moisture, temperature, and pressure within a particle. At E = 10,000 V/m, a pressure difference of 1.3 MPa and a temperature of over 300 C are obtained. Microwave fluidized-bed drying is capable of a much higher drying rate than conventional fluidized-bed drying, while it also maintains a low particle temperature. At a constant E, the drying time increases initially with the working load but gradually reaches a constant because of the limited moisture-carrying capacity of gas. The microwave power adsorbed by the particles decreases during the drying process, and some of the microwave energy can be lost to the fluidized gas for certain operating conditions. Although the advantage of a high heat- and mass-transfer coefficient associated with the fluidized bed does not contribute to water evaporation at a high load, fluidization is still important for achieving better product qualitymore » and a slightly higher drying rate when compared with microwave fixed-bed drying.« less

Twenty 7-azaindirubin derivatives were designed and synthesized. Their antitumor activities were evaluated in vitro against DU145 cell line. The pharmacological results showed that most of the prepared compounds displayed the excellent activity. Compound 18 exhibited the most potent antitumor activity among the tested compounds.

The fixed-bed drying of moist porous particles is described mathematically with a comprehensive heat and mass transfer model. The temperature, moisture content and pressure distributions in a particle were considered in the model along with the conjugate effects between the gas and particles in the fixed-bed. After dividing the deep bed into a series of thin layers, the fixed-bed drying model is solved layer by layer with finite difference method. The thin-layer model includes both the external and internal resistances of heat and mass transfer for particles in the bed. The numerical results show that non-uniformity exists not only for the temperature and relative humidity of gas in the fixed-bed, but also for the temperature, moisture content and pressure in the material. The drying behavior of each layer is significantly affected by the non-uniformity of drying conditions along the bed height. The distributions of temperature and moisture content in the particle play a very important role in heat and mass transfer in the fixed-bed drying. However, the effect of pressure distribution on the drying process is negligible. The calculation shows that a drying front exists in the fixed bed and moves forward linearly with drying time. The drying efficiency is higher in deep-bed drying than in thin layer drying up to a certain bed height.

In this study, we investigated the folding pathway of insulin precursor and compared it with that of insulin-like growth factor I (IGF-I). The intra-A chain disulphide bond was found to form early in insulin precursor folding, whereas the corresponding disulphide bond in IGF-I formed late. Intra-A chain disulphide-bond deleted [A6, A11-Ser] proteins, including proinsulin, insulin, and A chain, were employed for this investigation. Under the same conditions the recombination yield of insulin from S-sulphonates of native A and B chains was 22%, while the yield of [A6, A11-Ser] insulin from S-sulphonates of [A6, A11-Ser] A chain and native B chains was only approx. 7%. This indicated that the intra-A chain disulphide bond may serve to stabilize the A chain folding intermediate so as to facilitate the correct recognition and pairing with the B chain. Time courses of oxidation of reduced insulin A chains, reduced A and B chains, and reduced proinsulins showed that the intra-A chain disulphide bond formed first during insulin precursor folding. The formation of intra-A chain disulphide bond further accelerated the formation of the other two inter-chain disulphide bonds. The time course of helix structure formation of insulin A chains also indicated that the intra-A chain disulphide bond formed first, and could stabilize partially folded A chain helix structure. The rate of intra-A chain disulphide bond formation was almost the same as that for both helix structure formation and insulin molecule formation, indicating that the formation of the intra-A chain disulphide bond was the rate limiting step for the folding of insulin precursor.

A diffusion model of heat and mass transfer in moist porous media is obtained for low intensity convection drying found typically in food products and vegetable dehydration. The effective diffusivity was analyzed based on the coupled effects of moisture content and temperature on mass transfer in capillary flow, evaporation–condensation, and transition regions. The temperature effect was found to be significant in the transition and evaporation–condensation regions. The model was solved numerically using the finite difference method. Physical properties of banana were determined. The results show that the most intensive heat and mass transfer occur in the transition region where both capillary flow and vapor diffusion play a significant role. The length of the transition region is determined clearly by analyzing the liquid flux distribution in the material. Its value depends very much on the permeability of the material. The model proves that the assumption of evaporation front is valid for drying of very permeable materials. For the case of food and vegetable dehydration with the permeability below 10-19 m2, more comprehensive analysis is necessary.

A sublimation–condensation model is developed for freeze drying of unsaturated porous media. The governing equations describing the drying process are solved numerically with variable time step finite-difference method. The sublimation–condensation phenomena during microwave freeze drying are studied numerically for different operating conditions including electric field strength, sample thickness, and vacuum pressure. The results show that the sublimation–condensation effects depend on different drying conditions. For larger electric field strength, vapor transfer in sublimation–condensation region is more intensive and larger part of the vapor is sublimated from this region, so the effect of sublimation–condensation region on drying time is more significant. Too large electric field strength is not necessary for microwave freeze drying. In case of larger sample thickness, the saturation change of the sublimation–condensation region is larger, and the effect of sublimation–condensation region on drying time is more significant. The effect of vacuum pressure on drying time is not so significant in the observed range.

The heat and mass transfer during freeze drying of raw beef by different heating methods is studied theoretically and experimentally. The difference between radiant heating and microwave heating in freeze drying process has been analyzed. The results obtained are important for the selection of the heating methods in practical freeze dryers.

PURPOSE To achieve a combination therapy of targeted PDT and anti-VEGF for choroidal neovascularization (CNV). METHODS Arg-Gly-Asp (RGD)-modified liposomes encapsulating photocyanine and sorafenib (RGD-SSL-[P]-[S]) were prepared and characterized. Drug concentration in RGD-SSL-[P]-[S] and irradiation time were optimized on ARPE-19 and HUVEC cells in vitro. A laser-induced CNV rat model was used to assess the efficacy of this targeted combinational system. The effect of RGD-SSL-[P]-[S] on the retinal structure of BN rats was also examined. RESULTS The particle size of RGD-SSL-[P]-[S] was approximately 100 nm, with a encapsulation efficiency more than 90% for both photocyanine and sorafenib. From RGD-SSL-[P]-[S], the release rate of photocyanine was approximately 22%, whereas that of sorafeinb was approximately 40% at 48 hours. With the optimal drug concentration and irradiation time, RGD-SSL-[P]-[S] exhibited cytotoxicity only to HUVEC without obvious damage to normal ARPE-19 cells. Rats treated with RGD-SSL-[P]-[S] showed the least CNV area and fluorescein leakage in fluorescein fundus angiography. RGD-SSL-[P]-[S] was also found safe to the rat retina. CONCLUSIONS Combination of targeted PDT and anti-VEGF might be an effective therapy for CNV.

Recent findings have suggested that oxygenderived free radicals play an important role in the development and progression of acute pancreatitis. Therefore, the present study was designed to investigate whether metallothionein, a free radical scavenger, can protect against acute pancreatitis. Rats were injected intraperitoneally with zinc, followed by either an infusion of cerulein at 10 μg/kg for 4 h or a retrograde injection with 100 μl/100 g body weight of 5% sodium taurocholate into the pancreaticobiliary duct, in order to induce acute pancreatitis. Zn administration significantly increased the levels of both metallothionein and reduced glutathione in the pancreas; the metallothionein levels reached a peak of 83-fold of normal levels after 24 h. The indications of acute pancreatitis, as well as the mortality, were improved by Zn treatment before the onset of acute pancreatitis. Immunohistochemical studies showed that metallothionein accumulated in the acini of the pancreas in the Zn-treated groups, and with strong staining around the periphery of the vacuoles in the group treated with both Zn and cerulein. These findings suggested that Zn increased both metallothionein and glutathione levels in the pancreas and exerted a beneficial effect against ceruleinor taurocholate-induced acute pancreatitis in rats. Key Words: Metallothionein-Glutathione-Free radicals-Cerulein-Taurocholate-Pancreatitis.