Long-term IgE immunological tolerance to peanut allergens: An alternative to Noon's daily desensitization paradigm.

Herein, we show that profound afferent long-term peanut-allergen-specific IgE immunological tolerance for 3 to 9 months induced sustained unresponsiveness (SU) in naïve or peanut-sensitized rodents after peanut allergen immunization. Rodents were vaccinated sublingually with a peanut allergen extract or recombinant peanut allergen in chenodeoxycholate (CDCA), a fanesoid X receptor (FXR, NR1H4) agonist that downregulates SREBP-1c (sterol regulatory element binding protein-1c) and upregulates SHP in bone marrow-derived tolerogenic dendritic cells (DCs). Approximately 90 âˆ¼ 95 % of the total circulating PE-potentiated IgE and Ara h1, Ara h 2, and Ara h 6 peanut allergen-specific IgE responses were suppressed by recombinant peanut allergen-conjugated solid magnetic beads (sensitivity of 0.2 IU/ml). In contrast, peanut allergen-specific IgG production was not affected. Similarly, oleoylethanolamine (OEA), a peroxisome proliferator-activator receptor alpha (PPARα) agonist, and GW9662, a PPARγ antagonist, induced long-term peanut-specific IgE tolerance when administered via the sublingual, oral or i.p. route. Prophylactic Ara h2 DNA immunization with caNRF2 and IL-35 coexpression induced Ara h2 IgE tolerance. In summary, peanut allergen vaccination with select natural molecular ligands of nuclear receptors induced long-term peanut allergen-specific IgE tolerance via the afferent limb, which indicates that vaccination is an immune tolerance-promoting strategy that is effective at the DC level and that differs from Noon's daily desensitization program, which is effective at the mast cell level.

[Phytoplankton pigment patterns and community structure in the Yangtze Estuary and its adjacent areas].

Three cruises were carried out in the Yangtze Estuary and its adjacent areas in May, November, June during 2009-2010. The spatial variations of phytoplankton community structure were investigated based on RP-HPLC analysis of pigments and CHEMTAX processing of the pigment data. 21 kinds of pigments were detected, among which chlorophyll a, peridinin, fucoxanthin, 19'-butanoyloxyfucoxanthin, 19'-hexanoyloxyfucoxanthin, chlorophyll b, diadinoxanthin, alloxanthin and zeaxanthin were the major pigments in the Yangtze Estuary and its adjacent areas. Chlorophyll a was the most abundant in all pigments, followed by fuxoxanthin. Other pigments generally contributed a minor proportion to the total pigments. High concentrations of fucoxanthin and peridinin were observed in May 2009 and June 2010, indicating blooms of diatoms and dinoflagellates. The results showed that the composition and distribution of phytoplankton pigments were influenced by environmental factors. The phytoplankton community, as determined by biomarker pigment concentration using HPLC and CHEMTAX, was composed mainly of diatoms, dinoflagellates, cryptophytes, chlorophytes, cyanobacteria, prymnesiophytes, chrysophytes and prasinophytes. The dominant algal groups were diatoms, dinoflagellates and chlorophytes in May 2009. The phytoplankton community was characterized by high contribution of diatoms in November 2009. Diatoms, dinoflagellates and cryptophytes accounted for 62.5% of chlorophyll a in June 2010, and the relative abundance of cyanobacteria was higher in this cruise. The spatial variations of phytoplankton community structure featured distinct regionality. Diatoms, chlorophytes and cryptophytes were the main groups in the inshore waters, and the abundances of prymnesiophytes, chrysophytes and cyanobacteria were increasing from inshore to the open sea.

[Removal of Heterosigma akashiwo by modified wheat straw].

The modified wheat straw (MWS) was prepared and used to investigate the removal and the mechanism of Heterosigma akashiwo. The results showed that under the same loading of 0.10 g/L, the algal removal efficiency could reach 80% by MWS in 120 minutes, while 10% by the unmodified wheat straw. To investigate the mechanism, we measured the optical density of the supernatant at 260 nm. The result showed that the nucleotides were released, which meant disruption of the cytoplasmic membrane. More than 15% of the nucleotides were released from the cytoplasm under the effect of 0.15 g/L of MWS, indicating the irreversible damage on the cellular membrane, which resulted in the disintegration of the harmful algal cells. It is suggested that the low concentration of MWS might adsorb onto the algal cell surface and bind to the cytoplasmic membrane, which resulted in the flocculation. While the high concentration might cause the penetration into the cellular membrane, which resulted in the leakage of cytoplasm material and hence the death of cell.

[Effects of two organic pollutants on biomarker system of fish Lateolabrax japonicus and the pollution assessment].

Responses of a select suite of protective enzymes in Lateolabrax japonicus including superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (Gpx), reduced glutathione (GSH) glutathione S-transferase (GST), nitric oxide synthase (iNOS) in liver tissue and brain acetylcholinesterase (AChE), which could work as sensitively biochemical biomarkers were analyzed when exposed to different concentrations of sodium dodecylbenzene sulfonate (SDBS) and benzo[a]pyrene (B[a]P) under controlled laboratory conditions. Results showed that: (1) The biochemical biomarkers included in this investigation, different responses occurred in the enzymatic activities when exposed to different pollutants: the activities of SOD, GST, Gpx and GSH content were significantly induced by B[a]P (p < 0.05) while others present little different as compared to the control. Differently, SDBS exposure greatly affected the activities of CAT, Gpx, iNOS and AChE while showed little effect on the other evaluated biomarkers. Gpx was the most sensitive biomarker that sensitively indicated the organic pollution stress. (2) The simultaneous assay on heat shock protein 70 (Hsp70) expression was conducted by flow cytometry (FCM) and result presented that Hsp 70 expression could be effectively induced by SDBS as compared to the control throughout the experiment; however, B[a]P obviously induced Hsp70 during the first 12 d and then decreased to the level of the control. (3) The evaluated method of biomarker system combined with principal component analysis (PCA) could effectively distinguish different pollutants under controlled laboratory conditions and might be a promising and warning method for the early assessment of environmental change exposed to different organic pollutions.

[Effects of different phosphorus substrates on the growth and phosphatase activity of Skeletonema costatum and Prorocentrum donghaiense].

The effects NaH2PO4, adenosine disodium triphosphate (ATP), glucose 6-phosphate (G-6-P) and sodium beta-glycerophosphate (G-P) on the growth and phosphatase activity of Skeletonema costatum and Prorocentrum donghaiense were studied. The results showed that both species could utilize both dissolved inorganic phosphate (DIP) and dissolved organic phosphorus (DOP), and DOP had more effects on the growth of two species than DIP. For S. costatum, after 8 days, the cell abundances of the four treatments (NaH2PO4, ATP, G-6-P and G-P) were 48 x 10(4), 73 x 10(4), 63 x 10(4) and 54 x 10(4) cells/mL, respectively; For P. donghaiense, after 10 days, the cell abundances of the four treatments were 8.7 x 10(4), 15.5 x 10(4), 12.4 x 10(4) and 9.5 x 10(4) cells/mL, respectively. On the first 3-4 days, the phosphatase activity of all treatments of the two species showed a decreasing trend, but different changes were observed for the different phosphorus substrate treatments in latter days. For the NaH2PO4 treatment, both the AP and AcP activity of two species increased from the fifth day onwards. For S. costatum, the AP activity of the ATP and G-6-P treatment groups showed no obvious changes and AcP activity had a slight increase from the fifth day to the eighth day, while the activity of G-P treatment had highest phosphatase activity which increased from the fifth day on. At the end of the experiment, the AP activity of the three DOP treatment groups (ATP, G-6-P and G-P) was 0.004 x 10(-5), 0.014 x 10(-5) and 0.029 x 10(-5) U/cell, respectively, and the AcP activity was 0.006 x 10(-5), 0.011 x 10(-5) and 0.018 x 10(-5) U/cell, respectively. For P. donghaiense, both the AP and AcP activity of the three DOP treatments had similar trends, i.e., ATP < G-6-P < G-P. Under the same nutrient conditions, S. costatum had a much higher phosphatase activity and could absorb P from the environment much faster than P. donghaiense.

[Comparative research on the effects of different nutrient concentrations on the photopigment content and photosynthesis of two bloom-forming species isolated from the Changjiang River estuary].

The contents of cellular chlorophyll a (Chl-a), chlorophyll c (Chl-c), total coloured carotenoids (TCC) and the photosynthesis of Skeletonema costatum and Prorocentrum donghaiense under different nutrient conditions were studied. The results showed that both species in the low nutrient concentration conditions had lower cellular Chl-a, Chl-c and TCC content than those in the high nutrient concentration conditions. When the initial N/P ratio was 16/1 while the concentrations were different, the two species had different photosynthetic rate responses. For S. costatum, the photosynthetic rate normalized by cell in the low nutrient concentration group (64 micromol/L N and 4 micromol/L P) was significantly lower than that in the high concentration group (256 micromol/L N and 16 micromol/L P) from the fifth day, and at the end of the experiment (on the seventh day), the photosynthetic rate was 0.031 x 10(-4) micromol x (cell x h)(-1) and 0.13 x 10(-4) micromol x (cell x h)(-1) respectively, while the photosynthetic rate normalized by Chl-a was 12.92 micromol x (microg x h)(-1) and 13.03 micromol x (microg x h)(-1) for the two groups respectively, and there was no significant difference between them; however, for P. donghaiense, the photosynthetic rates normalized by both cell and Chl-a in the low concentration conditions (64 micromol/L N and 4 micromol/L P) were significantly higher than those in the high concentration conditions (256 micromol/L N and 16 micromol/L P). For the two species, when P was sufficient, the low N concentration group (64 micromol/L N and 36 micromol/L P) and when N was sufficient, the low P concentration group (883 micromol/L N and 4 micromol/L P) had higher photosynthetic rates normalized by both cell and Chl-a than the high N concentration group (256 micromol/L N and 36 micromol/L P) and the high P concentration group (883 micromol/L N and 16 micromol/L P) respectively. There was a significant positive relationship between the photosynthetic rate and the intracellular P for both species, and P. donghaiense had higher cellular photopigment contents and photosynthetic rates than S. costatum under the same nutrient conditions. It could be inferred from their photosynthetic characteristics that P. donghaiense would survive better in low nutrient conditions compared with S. costatum.

[Inhibitory effect of Gracilaria lemaneformis (Bory) Weber Bosse on the co-cultured Scrippsiella trochoidea (Stein) Loeblich III under controlled laboratory conditions].

The inhibitory effects of Grcilaria lemaneiformis on the co-cultured Scrippsiella trochoidea were determined under controlled laboratory conditions, and the possible mechanism was studied. Results showed that: (1) in the separating S. trochoiea-G. lemaneormis co-culture system when the initial cell density of C. lemaneaonis was set at 0.5 g x L(-1), the growth of S. trochoidea was obviously inhibited and its maximum cell density and exponential phase were decreased compared with the control; however, the inhibitory effect was not as strong as that in the direct cell-cell contact co-culture. Result showed that allelopathy basing on the direct cell contact was the most possible reason leading to the observed result; (2) when the initial cell density of G. lemaneiformis was set at 0.2 g'L-' in the direct cell-cell contact co-culture, the intracellular nitrate concentration of S. trochoidea in monoculture system was 1.5 times of that in co-culture. It seemed that G. lemaneiformis could competitively absorb the environmental nitrate and ultimately led to the decrease of the stock of intracellular nitrate of S. trochoidea.

[Mechanisms of removing red tide organisms by organo-clays].

We tested the influence of the preparation conditions of the quaternary ammonium compounds (QACs) modified clays on their capacities to remove red tide organisms, then discussed the mechanisms of the organo-clays removing red tide organisms. Hexadecyltrimethylammonium (HDTMA) improved the capacity of clays to flocculate red tide algae, and the HDTMA in metastable state enhanced the toxicity of the clay complexes to algae. The capacities of the organo-clays correlated with the toxicity and the adsorbed amount of the QACs used in clays modification, but as the incubation time was prolonged the stability of the organo-clays was improved and the algal removal efficiencies of the clay complexes decreased. When the adsorbed HDTMA was arranged in different clays in which the spatial resistance was different, there was more HDTMA in metastable state in the three-layer montmorillonite. Because of the homo-ion effect the bivalent or trivalent metal ions induced more HDTMA in metastable state and the corresponding organo-clays had high capacities to remove red tide organisms. When the reaction temperature was 60 degrees C the adsorbed HDTMA was easily arranged on cation exchange sites, if the temperature rose or fell the metastable HDTMA would increase so that the capacity of the clays was improved.

[Removal efficiency of red tide organisms by modified clay and its impacts on cultured organisms].

Removal efficiencies of Prorocentrum donghaiense (Prorocentrum dentatum) by Hexadecyltrimethylammonium (HDTMA) bromide and organo-clay modified by HDTMA were identified. Moreover the toxicity of the unbound HDTMA and HDTMA plus clay to aquacultural organisms, Penaeus japonicus, was also tested. The results suggested that (1) The unbound HDTMA had an excellent ability to remove the red tide organisms. However, its strong toxicity to Penaeus japonicus would restrict its practical use in red tide control. (2) The toxicity of HDTMA could be remarkably decreased by addition of clay and the organo-clay complex had a good ability to removal red tide organisms. At the same time the availability of organo-clay to remove the red tide of P. donghaiense and Heterosigma akashiwo in the lab-imitated cultures were studied. The results indicated that the organo-clay complex could remove 100% P. donghaiense at the dosage of 0.03 g/L and effectively control H. akashiwo at 0.09 g/L while the survival rate of Penaeus japonicus larvae, which were cultured in the red tide seawater, is kept 100%. According to the results in laboratory, the mesocosm tests (CEPEX) in East China Sea were conducted in April and May of 2003. The removal efficiencies of original clay, organic clay and inorganic clay were compared during the CEPEX tests. The results revealed that both inorganic clay and organic clay could remove red tide organisms more effectively than the original clay.