The lumen-facing domain is important for the biological function and organelle-to-organelle movement of bZIP28 during ER stress in Arabidopsis

The membrane-associated transcription factor, bZIP28, is relocated from the endoplasmic reticulum (ER) to the Golgi and proteolytically released from the membrane mediated by two proteases, S1P and S2P, in response to ER stress in Arabidopsis. The activated N-terminal domain recruits nuclear factor Y (NF-Y) subunits in the nucleus to regulate ER stress downstream genes. Little is known about the functions of the bZIP28 C-terminal lumen-facing domain. Here, we provide novel insights into how the ER lumen-facing domain affects the biological function and organelle-to-organelle movement of bZIP28 in the ER stress response. First, we demonstrated the functional redundancy of bZIP28 and bZIP60 by generation and analysis of the bZIP28 and bZIP60 double mutant zip28zip60. Subsequent genetic complementation experiments in zip28zip60 background with deletions on bZIP28 lumen-facing domain highlighted the importance of lumen-facing domain for its in vivo function of bZIP28 in the ER stress response. The protein subcellular localization and Western blotting results further revealed that the bZIP28 lumen-facing domain contains ER retention signal which is important for the proteolytic activation of bZIP28. Thus, the bZIP28 lumen-facing C-terminus plays important roles in the ER-to-Golgi movement of bZIP28, which may contribute to the sensing of the ER stress.

Transcriptomic analysis of cadmium stress response in the heavy metal hyperaccumulator Sedum alfredii Hance

The Sedum alfredii Hance hyperaccumulating ecotype (HE) has the ability to hyperaccumulate cadmium (Cd), as well as zinc (Zn) and lead (Pb) in above-ground tissues. Although many physiological studies have been conducted with these plants, the molecular mechanisms underlying their hyper-tolerance to heavy metals are largely unknown. Here we report on the generation of 9.4 gigabases of adaptor-trimmed raw sequences and the assembly of 57,162 transcript contigs in S. alfredii Hance (HE) shoots by the combination of Roche 454 and Illumina/Solexa deep sequencing technologies. We also have functionally annotated the transcriptome and analyzed the transcriptome changes upon Cd hyperaccumulation in S. alfredii Hance (HE) shoots. There are 110 contigs and 123 contigs that were up-regulated (Fold Change ≧2.0) and down-regulated (Fold Change ≦0.5) by chronic Cd treatment in S. alfredii Hance (HE) at q-value cutoff of 0.005, respectively. Quantitative RT-PCR was employed to compare gene expression patterns between S. alfredii Hance (HE) and non-hyperaccumulating ecotype (NHE). Our results demonstrated that several genes involved in cell wall modification, metal translocation and remobilization were more induced or constitutively expressed at higher levels in HE shoots than that in NHE shoots in response to Cd exposure. Together, our study provides large-scale expressed sequence information and genome-wide transcriptome profiling of Cd responses in S. alfredii Hance (HE) shoots.

Clinical analysis of 73 cases of intraspinal nerve sheath tumor

Seventy-three patients with spinal nerve sheath tumor who were surgically treated in our hospital during the years 2004-2010 were retrospectively reviewed with respect to recovery of neurological function, recurrence of the tumor and occurrence of kyphotic deformities. Preoperative clinical manifestations, imaging data, surgical records and follow-up results were comprehensively analyzed. The follow-up duration was 12-60 months with an average of 32.0 months. Out of the 73 cases enrolled, 69 had gradual recovery of sensation, motor and sphincter functions 1 week to 3 months after operation. Forty-six cases had incomplete paralysis, whose American Spinal Injury Association (ASIA) grades, however, were gradually increased during the follow-up period, 4 cases had no significant improvement of the clinical symptoms and no change in ASIA grades during the follow-up period. Two cases had postoperative recurrence of the tumor. There were no deaths, no spinal instability, and no kyphotic malformations found in any cases. Our study indicated that complete removal of the tumor is important for good recovery, and an ideal surgical method may reduce the recurrence of the tumor or the occurrence of complications.

Effects of Saccharomyces cerevisiae fermentation product on in vitro fermentation and microbial communities of low-quality forages and mixed diets

Two experiments were conducted to investigate the effects of a Saccharomyces cerevisiae fermentation product (XP, Diamond V, Cedar Rapids, IA) on in vitro ruminal fermentation of single forage and mixed diets. In Exp. 1, an in vitro test was used to determine the effects of various concentrations (0, 1, 2, and 3 g/L) of XP on ruminal fermentation of the major forage sources of China (rice straw, RS; corn stover, CS; corn silage without grain, CSNG; and corn silage with grain, CSG). Total VFA reached a peak at 1 g/L XP for RS, CSNG, and CSG and increased linearly (P < 0.01) for CS. The molar proportion of acetate decreased and propionate increased linearly (P < 0.01) with an increasing amount of XP for RS, CS, and CSNG. Microbial protein (MCP) increased linearly (P < 0.01) with an increasing level of XP for RS, and it reached peak values at 1 and 2 g/L XP for CSG and CSNG, respectively. Fungi population was increased (P < 0.05) with 1 g/L XP for all forages except CSNG. The population of Ruminococcus flavefaciens increased (P < 0.05) at 1 or 2 g/L XP for RS, CSNG, and CSG. In Exp. 2, the effects of 3 concentrations of XP (0, 1, and 2 g/L) were tested on in vitro ruminal fermentation of 3 mixed diets with various ingredient combinations: 1) CSC (corn:soybean meal:corn stover = 33:22:45), 2) CSCC (corn:soybean meal:corn stover:corn silage = 33:22:22.5:22.5), and 3) CSCCA (corn:soybean meal:corn stover:corn silage:alfalfa = 33:22:19:21:5). Total VFA concentrations were influenced by diets (P < 0.01) and were enhanced linearly by increasing concentrations of XP (P < 0.01). The molar proportion of acetate was reduced (P < 0.01), but the propionate proportion was enhanced with increasing concentrations of XP (P < 0.01). Ammonia N was decreased and MCP was increased by the addition of XP (linear, P < 0.01; quadratic, P < 0.05). The fungi population was greater with XP addition (quadratic, P < 0.01). The percentage of R. albus was affected by diets (P < 0.01), the level of XP (linear and quadratic, P < 0.01), and their interaction (P < 0.01). From these 2 in vitro studies, it is inferred that the addition of XP could improve the rumen fermentation of forages and mixed diets by stimulating the number of fiber-digesting rumen microbes, especially fungi populations.

Dexmedetomidine versus remifentanil sedation during awake fiberoptic nasotracheal intubation: a double-blinded randomized controlled trial

BACKGROUND

Awake fiberoptic nasotracheal intubation is usually performed in patients with an anticipated difficult airway. This study compares dexmedetomidine and remifentanil for conscious sedation during fiberoptic intubation.

METHODS

Forty patients undergoing elective awake fiberoptic nasotracheal intubation were allocated randomly to receive either dexmedetomidine (n = 20) or remifentanil (n = 20). Primary outcome measures were endoscopy, intubation, and post-intubation conditions as scored by the attending anesthesiologist. Other parameters included the time taken to achieve the desired level of sedation, endoscopy time, intubation time, and hemodynamic changes during the procedure. An interview was conducted 24 h after surgery to evaluate patients' recall of and satisfaction with the procedure.

RESULTS

The median [interquartile range] endoscopy score (graded 0-5) in the dexmedetomidine group (2 [1-2]) was significantly better than in patients who received remifentanil (3 [2-3]; p < 0.01). Recall of intubation was significantly lower in the dexmedetomidine group (p = 0.027). Dexmedetomidine provided better patient satisfaction than remifentanil (2 [1-2] and 2 [2-3], respectively; p = 0.022). Patients in the dexmedetomidine group had fewer heart rate responses during endoscopy and intubation as compared to the remifentanil group (p < 0.001 and p = 0.004, respectively). Peripheral oxygen saturation was less in the remifentanil group during endoscopy (p = 0.003). There were no significant differences in intubation and post-intubation conditions.

CONCLUSIONS

Both dexmedetomidine and remifentanil were effective as sedatives in patients undergoing awake fiberoptic nasotracheal intubation. Compared with remifentanil, dexmedetomidine offered better endoscopy scores, lower recall of intubation, and greater patient satisfaction, with minor hemodynamic side effects.

Effects of broccoli stem and leaf meal on broiler performance, skin pigmentation, antioxidant function, and meat quality

Three hundred sixty 1-d-old Ross 308 male broilers were used to study the effects of broccoli stem and leaf meal (BSLM) on growth performance, skin pigmentation, antioxidant function, and meat quality. The chicks were fed 4 diets containing different levels (0, 4.0, 8.0, and 12.0%) of BSLM as partial replacement for corn and soybean meal for a period of 42 d. The results showed that dietary supplementation of BSLM had no effect (P > 0.05) on growth performance. As compared with control, dietary 4%, 8%, and 12% BSLM increased (P < 0.05) b value (yellowness) both in shank and breast skin, increased (P < 0.05) the concentrations of xanthophylls in abdominal fat and breast skin, improved (P < 0.05) total antioxidant capability, lowered malondialdehyde concentration, and decreased drip loss percentage of breast muscle. Dietary 8% and 12% BSLM decreased (P < 0.05) shank L values (lightness), increased (P < 0.05) shank a value (redness), and increased (P < 0.05) the activities of superoxide dismutase and catalase of breast muscle as compared with control. The results indicated that dietary supplementation of BSLM in broiler chickens improved the poultry products quality with the more skin pigmentation and the less drip loss percentage of breast meat. The more skin pigmentation mainly related to the high amount of xanthophylls in BSLM. The decreased meat drip loss fed BSLM may be caused by the antioxidative function of BSLM.

Selective cognitive impairments are related to selective hippocampus and prefrontal cortex deficits after prenatal chlorpyrifos exposure

Prenatal exposure to chlorpyrifos (CPF) leads to cognitive impairments in adulthood. The cytoarchitectural basis is unclear. In the present study, we assessed the effects of prenatal CPF exposure on T-maze delayed alternation task and the win-shift/lose-shift responses associated with the morphology of the dorsal hippocampus (dHPC) and the medial prefrontal cortex (mPFC) in adult animals. Gestational ICR female mice were exposed to 0, 1 or 5mg/kg/d of CPF through gestational days 13-17. Behavioral experiments were performed on postnatal days (PD) 45-60 of the male and female offsprings; morphological samples were collected on PD 60. Our behavioral study results showed a gradual increase in the number of lose-shift errors on increased memory loads in the 5mg/kg/d CPF-treated males. A weak initial increase in the number of lose-shift errors was observed in the females. In all of the groups, no significant differences were observed in the number of win-shift errors and correct of the first choice. The morphological studies showed extensive condensed nucleus and enlarged intercellular spaces in the CA1 and DG sub-regions in the dHPC of the CPF-treated males and the DG sub-region of the CPF-treated females. The cell count was significantly reduced in these sub-regions. The morphological studies showed no obvious abnormalities at PrL and IL of mPFC in the CPF-treated males and females, but the cell count was reduced. Our findings suggest that prenatal CPF exposure at 5mg/kg/d induces selective cognitive impairments, which based on the morphological deficits in the dHPC and the mPFC.

Pentamethylquercetin generates beneficial effects in monosodium glutamate-induced obese mice and C2C12 myotubes by activating AMP-activated protein kinase

AIMS/HYPOTHESIS

Pentamethylquercetin (PMQ) has recently been shown to have glucose-lowering properties. Here, we aimed to characterise the effectiveness and underlying mechanisms of PMQ for ameliorating metabolic disorders in vivo and vitro.

METHODS

We generated a mouse model of obesity by neonatal administration of monosodium glutamate (MSG) and used it to assess the properties of PMQ as a treatment for metabolic disorders. We also investigated the possible underlying mechanisms of PMQ in the prevention of metabolic disorders.

RESULTS

Compared with normal mice, MSG mice had metabolic disorders, including central obesity, hyperinsulinaemia, insulin resistance, hyperglycaemia, hyperlipidaemia, decreased phosphorylation of AMP-activated protein kinase (AMPK) and acetyl-CoA carboxylase (ACC), and downregulated levels of GLUT4 in gastrocnemius muscles. In MSG mice, PMQ treatment (5, 10, 20 mg/kg daily) reduced body weight gain, waist circumference, adipose tissue mass, serum glucose, triacylglycerol and total cholesterol, while improving insulin resistance, activating AMPK and increasing ACC phosphorylation and GLUT4 abundance. In C2C12 myotubes, PMQ (10 μmol/l) increased glucose consumption by ∼65%. PMQ treatment (1-10 μmol/l) also activated AMPK, increased ACC phosphorylation and GLUT4 abundance, and upregulated the expression of some key genes involved in fatty acid oxidation.

CONCLUSIONS/INTERPRETATION

These findings suggest that PMQ can ameliorate metabolic disorders at least in part via stimulation of AMPK activity.

Electron bow-wave injection of electrons in laser-driven bubble acceleration

An electron injection regime in laser wake-field acceleration, namely electron bow-wave injection, is investigated by two- and three-dimensional particle-in-cell simulation as well as analytical model. In this regime electrons in the intense electron bow wave behind the first bubble catch up with the bubble tail and are trapped by the bubble finally, resulting in considerable enhancement of the total trapped electron number. For example, with the increase of the laser intensity from 2 × 10(19) to 1 × 10(20) W/cm(2), the electron trapping changes from normal self-injection to bow-wave injection and the trapped electron number is enhanced by two orders of magnitude. An analytical model is proposed to explain the numerical observation.

Conservation of IRE1-regulated bZIP74 mRNA unconventional splicing in rice (Oryza sativa L.) involved in ER stress responses

Protein folding in the endoplasmic reticulum (ER) is a fundamental process in plant cells that is vulnerable to many environmental stresses. When unfolded or misfolded proteins accumulate in the ER, the well-conserved unfolded protein response (UPR) is initiated to mitigate the ER stress by enhancing the protein folding capability and/or accelerating the ER-associated protein degradation. Here, we report the conservation of the activation mechanism of OsbZIP74 (also known as OsbZIP50), an important ER stress regulator in monocot plant rice (Oryza sativa L.). Under normal conditions, OsbZIP74 mRNA encodes a basic leucine-zipper transcription factor with a putative transmembrane domain. When treating with ER stress-inducing agents such as tunicamycin and DTT, the conserved double stem-loop structures of OsbZIP74 mRNA are spliced out. Thereafter, the resulting new OsbZIP74 mRNA produces the nucleus-localized form of OsbZIP74 protein, eliminating the hydrophobic region. The activated form of OsbZIP74 has transcriptional activation activity in both yeast cells and Arabidopsis leaf protoplasts. The induction of OsbZIP74 splicing is much suppressed in the OsIRE1 knock-down rice plants, indicating the involvement of OsIRE1 in OsbZIP74 splicing. We also demonstrate that the unconventional splicing of OsbZIP74 mRNA is associated with heat stress and salicylic acid, which is an important plant hormone in systemic acquired resistance against pathogen or parasite.

Arsenic compounds: revived ancient remedies in the fight against human malignancies

Arsenic, the 20th most abundant element in the earth crust, is one of the oldest drugs in the world. It was used in the 18th century in treating hematopoietic malignancies, discarded in 1950s in favor of chemotherapeutic agents (busulphan and others), and was revived in the 1970s due to its dramatic efficacy on acute promyelocytic leukemia (APL) driven by the t(15;17) translocation-generated PML-RARα fusion. Arsenic represents the most potent single agent for APL, and achieves a five-year overall survival of 90% in APL patients when combined with all-trans retinoic acid (ATRA) and chemotherapy (daunorubicin and cytarabine), turning this disease from highly fatal to highly curable. Arsenic triggers sumoylation/ubiquitination and proteasomal degradation of PML-RARα via directly binding to the C3HC4 zinc finger motif in the RBCC domain of the PML moiety and induction of its homodimerization/multimerization and interaction with the SUMO E2 conjugase Ubc9. Because of its multiplicity of targets and complex mechanisms of action, arsenic is widely tested in combination with other agents in a variety of malignancies. Other arsenic containing recipes including oral formulations and organic arsenicals are being developed and tested, and progress in these areas will definitely expand the use of arsenicals in other malignant diseases.

In vitro rumen fermentation and methane production are influenced by active components of essential oils combined with fumarate

Two trials were conducted to identify the optimal levels of essential oil active components (EOAC) and their combination with fumarate on in vitro rumen fermentation. In trial 1, eugenol, carvacrol, citral and cinnamaldehyde were mixed at ratios of 1:2:3:4, 2:1:4:3, 3:4:1:2, 4:3:2:1 and 1:1:1:1 to make up five combinations (EOAC1, EOAC2, EOAC3, EOAC4 and EOAC5 respectively). The mixtures were supplied at levels of 0, 50, 200 or 500 mg/l to identify the optimal combination for methane reduction. Methane production and ammonia nitrogen were decreased by adding EOAC, irrespective of component compounds, but the production of gas and total volatile fatty acids (VFA) were also decreased. Hydrogen balance analysis indicated that the ratio of hydrogen consumed via methane to hydrogen consumed via VFA was lowest at 200 mg/l of EOAC5 treatment, from which the proportional change in methane was more than the change in VFA, with 31.5% of methane reduction and 12.9% of VFA reduction. In trial 2, 200 mg/l of EOAC5 was added with 0, 5, 10 and 15 mm monosodium fumarate to see whether fumarate had a further effect on rumen fermentation. The addition of fumarate had no influence on gas production, but it further decreased methane and increased the total VFA in comparison with EOAC added solely, with the greatest decrease occurring in methane (78.1%) from 10 mm of fumarate. Quantification of the microbial populations in rumen fluids by RT-PCR showed that methanogen, protozoa, fungi, Fibrobacter succinogenes and Ruminococcus flavefaciens populations were significantly decreased by EOAC5, but were not influenced by fumarate. In summary, the addition of EOAC had consistent effects on rumen fermentation parameters, but high levels of EOAC would induce the inhibition of rumen fermentation. Adding fumarate can enhance the methane-inhibiting effect of EOAC, and the decrease was higher than that calculated stoichiometrically.

Reversible and irreversible drought-induced changes in the anther proteome of rice (Oryza sativa L.) genotypes IR64 and Moroberekan

Crop yield is most sensitive to water deficit during the reproductive stage. For rice, the most sensitive yield component is spikelet fertility and the most sensitive stage is immediately before heading. Here, we examined the effect of drought on the anther proteome of two rice genotypes: Moroberekan and IR64. Water was withheld for 3 d before heading (3DBH) in well watered controls for 5 d until the flag leaf relative water content (RWC) had declined to 45-50%. Plants were then re-watered and heading occurred 2-3 d later, representing a delay of 4-5 d relative to controls. The anther proteins were separated at 3 DBH, at the end of the stress period, and at heading in stressed/re-watered plants and controls by two-dimensional (2-D) gel electrophoresis, and 93 protein spots were affected reproducibly in abundance by drought during the experiment across two rice genotypes. After drought stress, upon re-watering, expressions of 24 protein spots were irreversible in both genotypes, 60 protein spots were irreversible in IR64 but reversible in Moroberekan, only nine protein spots were irreversible in Moroberekan while reversible in IR64. Among them, there were 14 newly drought-induced protein spots in IR64; none of them was reversible on re-watering. However, there were 13 newly drought-induced protein spots in Moroberekan, 10 of them were reversible on re-watering, including six drought-induced protein spots that were not reversed in IR64. Taken together, our proteomics data reveal that drought-tolerant genotype Moroberekan possessed better recovery capability following drought and re-watering at the anther proteome level than the drought-sensitive genotype IR64. The disruptions of drought to rice anther development and pollen cell functions are also discussed in the paper.

Effects of tripeptides and lactogenic hormones on oligopeptide transporter 2 in bovine mammary gland

This study was conducted to investigate the expression of oligopeptide transporter 2 (PepT2) and its potential function in bovine mammary gland. First, the PepT2 mRNA and protein were determined in cultured mammary epithelial cells. Then the effects of lactogenic hormones (prolactin, hydrocortisone or insulin) and substrate (threonyl-phenylalanyl-phenylalanine) on PepT2 were investigated. The PepT2 mRNA and protein were successfully detected in bovine mammary epithelial cells. PepT2 gene expression was enhanced by the addition of 50, 500 and 5000 ng/ml prolactin, 10 and 100 ng/ml hydrocortisone, and 50, 500, 5000 and 50,000 ng/ml insulin. PepT2 mRNA abundance was increased when 5, 10 and 15% of threonyl-phenylalanyl-phenylalanine was included. Responses of PepT2 to lactogenic hormones and oligopeptide inferred that it may play an important role in bovine mammary gland.

+Antisense oligonucleotide targeting survivin inhibits growth by inducing apoptosis in human osteosarcoma cells MG-63

Survivin may play an important role in the development of osteosarcoma. In this study, we chose osteosarcoma cell line MG-63, which highly expressed survivin, to observe the effects of antisense oligonucleotide targeting survivin on the apoptosis induction and proliferation inhibition. It was shown in our results that the apoptosis rate and the proliferation inhibition rate increased significantly in survivin-positive cells MG-63 by using MTT and flow cytometry methods. We found that the growth inhibition rate and apoptosis rate were changed in a dose-dependent way. When the concentration of antisurvivin oligonucleotide was 600 nM, the effects reached the peak. RT-PCR and western-blot methods were used to detect the mRNA and protein expression of survivin in MG-63. We observed that the mRNA and protein expression of survivin reduced after transfected with antisurvivin oligonucleotides at the concentration of 200 nM, 400 nM and 600 nM. At the same time, we found that the mRNA and protein expression of Fas were up-regulated with the concentration of antisurvivin oligonucleotides from 200 nM to 600 nM. It was negative associated with the expression change of survivin. These data suggested that survivin should play an important role in the development of osteosarcoma and the survivin blockaded by using antisurvivin oligonucleotide could inhibit the proliferation and induce apoptosis of osteosarcoma by decreasing the expression of survivin and activate the Fas-mediated apoptosis. Down-regulation of survivin by antisense oligonucleotide might be an effective strategy to the treatment of osteosarcoma and might improve the therapeutic effect.

KEYWORDS

osteosarcoma, Survivin, apoptosis, Fas.

Effects of dietary supplementation of methionine and lysine on milk production and nitrogen utilization in dairy cows

The effect of the content of lysine and methionine in metabolizable protein (MP) on lactation performance and N utilization in Chinese Holstein cows was determined. A control diet (C) was formulated to be adequate in energy but slightly limiting in MP. The concentration of Met and Lys in MP was 1.87 and 5.93%, respectively. The treatments were as follows (% of Met or Lys in MP): L=diet C supplemented with L-lysine-HCl at 0.49% on a dry matter (DM) basis (Met, 1.87; Lys, 7.00); M=diet C supplemented with 2-hydroxy-4-(methylthio)-butanoic acid (HMB) at 0.15% (Met, 2.35; Lys, 5.93); ML=diet C supplemented with 0.49% L-lysine HCl and 0.15% HMB (Met, 2.39; Lys, 7.10). The diets were fed to 60 Chinese Holsteins in mid-lactation (average days in milk=120, and milk yield=32.0 kg/d) for 8 wk. Milk yield was increased by supplementation of either Lys (1.5 kg/d) or Met (2.0 kg/d), and supplementation of both Lys and Met further increased milk yield (3.8 kg/d). There was no significant difference in dry matter intake across treatment groups. Cows on treatments M (3.95%) and ML (3.90%) had higher milk fat content than those on C (3.60%) and L (3.67%), but there were no significant differences in milk protein and lactose contents or somatic cell count among treatments. Supplementation of Met or Lys significantly increased Met or Lys concentration in arterial plasma. Treatment ML had a higher conversion of intake N to milk N and lower urea N concentrations in serum, urine, and milk than did treatment C. Supplementing HMB and L-lysine-HCl to provide approximately 2.3% Met and 7.0% Lys of the MP in diets slightly limiting in MP increased milk production, milk protein yield, and N utilization efficiency.

Effect of different rumen-inert fatty acids supplemented with a dietary antioxidant on performance and antioxidative status of early-lactation cows

The objective of the study was to evaluate the effect of diets supplemented with fatty acids of different degrees of saturation, in the absence or presence of an antioxidant (AOX; Agrado Plus, Novus International Inc., St. Charles, MO), on dairy cow lactation performance. Calcium salts of long-chain fatty acids were supplemented as a source of lower saturation fatty acid, and a palm acid product was supplemented as the higher saturation fatty acid source. Sixty early-lactation Chinese Holstein cows (100+/-23 d in milk) were randomly allocated to 4 dietary treatments in a 2 x 2 factorial design: (1) lower saturation fatty acid (LS), (2) LS and AOX, (3) higher saturation fatty acid (HS), and (4) HS and AOX. The Ca salts of long-chain fatty acids and palm acid product were supplied at 1.8 and 1.5% on a dry matter basis, respectively, to form isoenergetic diets. The AOX was added at 0.025% in the ration. The experiment lasted 9 wk, including 1 wk for adaptation. Lactation performance was recorded and milk was sampled and analyzed weekly. Blood samples were taken from the coccygeal vein to determine metabolism parameters on d 16, 36, and 56 during the experiment. Neither fatty acid type nor AOX supplementation showed a significant effect on dry matter intake during the study. Milk yield was lower in the LS-fed cows compared with the cows fed HS. Milk fat and milk protein concentrations were not affected by fatty acid type or AOX supplementation. Adding AOX increased the yield of milk in the LS-fed cows, but did not affect those fed HS. Activity of plasma superoxide dismutase was significantly lower, plasma glucose tended to be lower, and plasma malondialdehyde was higher in the LS-fed animals compared with those fed HS. Addition of AOX decreased both plasma nonesterified fatty acids and hydrogen peroxide contents and increased total antioxidant capacity across the fatty acid types. Plasma beta-hydroxybutyrate was not affected by fatty acid type or AOX treatment. Cows fed LS had higher cis-9C(18:1) and trans-10, cis-12C(18:2) in milk at the expense of C(18:0), whereas AOX addition increased milk cis-9C(18:1) at the expense of milk C(12:0), C(16:0), and trans-10, cis-12C(18:2). It is inferred that feeding LS resulted in inferior lactation performance, whereas addition of antioxidant partially alleviated these negative effects.

Endoplasmic reticulum protein quality control and its relationship to environmental stress responses in plants

The endoplasmic reticulum (ER) has a sophisticated quality control (QC) system to eliminate improperly folded proteins from the secretory pathway. Given that protein folding is such a fastidious process and subject to adverse environmental conditions, the ER QC system appears to have been usurped to serve as an environmental sensor and responder in plants. Under stressful conditions, the ER protein folding machinery reaches a limit as the demands for protein folding exceed the capacity of the system. Under these conditions, misfolded or unfolded proteins accumulate in the ER, triggering an unfolded protein response (UPR). UPR mitigates ER stress by upregulating the expression of genes encoding components of the protein folding machinery or the ER-associated degradation system. In Arabidopsis thaliana, ER stress is sensed and stress signals are transduced by membrane-bound transcription factors, which are activated and mobilized under environmental stress conditions. Under acute or chronic stress conditions, UPR can also lead to apoptosis or programmed cell death. Despite recent progress in our understanding of plant protein QC, discovering how different environmental conditions are perceived is one of the major challenges in understanding this system. Since the ER QC system is one among many stress response systems in plants, another major challenge is determining the extent to which the ER QC system contributes to various stress responses in plants.

bZIP28 and NF-Y transcription factors are activated by ER stress and assemble into a transcriptional complex to regulate stress response genes in Arabidopsis

Stress agents known to elicit the unfolded protein response in Arabidopsis thaliana upregulate the expression of a constellation of genes dependent on the membrane-associated basic domain/leucine zipper (bZIP) transcription factor, bZIP28. Among the stress-activated genes, a consensus promoter sequence corresponding to the endoplasmic reticulum (ER) stress-responsive element I (ERSE-I), CCAAT-N10-CACG, was identified. Disruption of either the CCAAT or CACG subelement in ERSE-I resulted in reduction of the transcriptional response to ER stress. bZIP28 forms homo- and heterodimers with other bZIP TF family members (in subgroup D) and interacts with CCAAT box binding factors, heterotrimeric factors composed of NF-Y subunits. Arabidopsis encodes 36 NF-Y subunits, and it was found that subunits NF-YB3 and -YC2 interact with bZIP28 and NF-YA4, respectively, in a yeast three-hybrid system. A transcriptional complex containing bZIP28 and the above-mentioned three NF-Y subunits was assembled in vitro on DNA containing ERSE-I. bZIP28, on its own, binds to the CACG subelement in ERSE-I to form a smaller complex I, and in combination with the NF-Y subunits above, bZIP28 assembles into a larger transcriptional complex (complex II). bZIP28 was shown to interact with NF-Y subunits in vivo in bimolecular fluorescence complementation analyses and in coimmunoprecipitation assays. Treatment of seedlings with ER stress agents led to the upregulation of NF-YC2 and the relocation of NF-YB3 from the cytoplasm to the nucleus. Thus, in response to ER stress, bZIP28 is mobilized by proteolysis and recruits NF-Y subunits to form a transcriptional complex that upregulates the expression of ER stress-induced genes.

Regulation and processing of a plant peptide hormone, AtRALF23, in Arabidopsis

Arabidopsis has 34 genes encoding proteins related to rapid alkalinization factor (RALF), a peptide growth factor. One of those genes (AtRALF23) is significantly downregulated by brassinolide (BL) treatment of Arabidopsis seedlings or in mutant seedlings expressing a constitutively active form of BES1, a transcriptional effector of the brassinosteroid signaling pathway. Overexpression of AtRALF23 impairs BL-induced hypocotyl elongation in seedlings, and mature overexpressing plants are shorter and bushier. Overexpression of AtRALF23 produces slower growing seedlings, with roots that have reduced capacity to acidify the rhizosphere. AtRALF23 encodes a 138-aa protein, and when an epitope-tagged form (AtRALF23-myc) was expressed in transgenic plants, the protein was processed to release a C-terminal peptide. The presumed junction between the precursor and the processed peptide contains a recognition site for site-1 protease (AtS1P), a plant subtilisin-like serine protease (subtilase). When AtRALF23-myc was expressed in the background of a site-1 protease mutant (s1p-3), or when the AtS1P recognition site (RRIL) was mutated (RR --> GG) and expressed in a wild-type background, the precursor was not cleaved, and the bushy phenotype was not produced. A fluorogenic peptide representing the presumed subtilase recognition site in AtRALF23 was cleaved in vitro by AtS1P. Thus, BL downregulates AtRALF23 expression, presumably relieving the growth-retarding effect of a peptide growth factor, which is processed from a larger precursor protein by AtS1P.

Overexpression of an Arabidopsis gene encoding a subtilase (AtSBT5.4) produces a clavata-like phenotype

Arabidopsis thaliana encodes 56 subtilisin-like serine proteases (subtilases), and some are involved in the proteolytic processing of plant peptide hormones. Here, we have investigated the role of one subtilase, AtSBT5.4, in whole plant physiology by examining gain- or loss-of-function phenotypes. Knockouts of AtSBT5.4 had no apparent phenotype; however, overexpression produced a clavata-like phenotype with fasciated inflorescence stems and compounded terminal buds. Production of the phenotype depended on the enzymatic activity of the subtilase, because substitution of serine at the active site abolished the overexpression phenotype. When AtSBT5.4 was overexpressed in a clavata3 mutant background, a novel phenotype was produced suggesting that AtSBT5.4 interacts with the clavata signaling pathway. However, AtSBT5.4 did not cleave CLAVATA3 (CLV3) or a fluorogenic peptide representing the putative cleavage site in CLV3 under in vitro conditions suggesting that the interaction in vivo does not involve the cleavage of CLV3. Overexpression of AtSBT5.4 in a wuschel (wus) background suppressed the AtSBT5.4 overexpression phenotype indicating that WUS function is required for the AtSBT5.4 overexpression phenotype.

Primary Biliary Cirrhosis-Related Autoimmune Hemolytic Anemia: Three Case Reports and Review of the Literature

The association between primary biliary cirrhosis (PBC) and autoimmune hemolytic anemia (AIHA) is uncommon; only fourteen such case reports have been described. In this report, three patients who developed AIHA on the basis of PBC underwent successful therapy with corticosteroids and ursodeoxycholic acid (UDCA). Patient 3 was more complicated, suffering from PBC, Evans syndrome, Sjögren syndrome and Klinefelter syndrome simultaneously. This has not previously been reported in the world literature. Review of all fifteen cases showed that there is a prominent occurrence sequence that AIHA might take place on the basis of PBC. With sufficient doses of corticosteroids or immunosuppressant therapy, besides hemolysis under effective control, liver function also improved. According to the criteria of secondary AIHA, we may call them PBC-related AIHA. Thus, patients with PBC with serum bilirubin levels rising suddenly should undergo screening for associated hemolysis. Recommended treatment for PBC-related AIHA includes sufficient doses of corticosteroids to control the hemolysis in the acute phase, and immunosuppressant or adequate dose of UDCA to maintain therapy. These case reports have been increasing in recent years, so further reserch is needed to illustrate the incidence and natural courses of these two organ-specific autoimmune diseases.

Study on the relationship between meteorological conditions and acid rain in mid-eastern Fujian

Based on the acid rain observation data and the contemporaneous historical synoptic charts of Mid-Eastern Fujian during the period of 1991 to 2003, we analyzed the distribution characteristics of acid rain in different seasons, weather types, precipitation grades and wind directions. The results showed that the acid pollution in Mid-Eastern Fujian was still serious. In winter, the precipitation pH value was 4.79, and the acid rain frequency was 60.62% which was twice higher than that in summer. The pH value of warm shear-type precipitation at 850 hPa was 4.79. Nearly half of these precipitations had the problems of acid rain pollution. The acid rain frequency of the inverted trough type was only 26.11% which was the lowest one in all types. There was no marked difference of the acid rain distribution characteristics between ahead-of-trough and behind-the-trough. The precipitation pH values of the five grades were lower than 5.30 and the acid rain frequency changed as an inverted U shape with the increasing of the rainfall. The pH values of precipitations in the eight wind directions were generally below 5.20, and the acid rain frequencies were about 40%.

Fate of nonylphenol polyethoxylates and their metabolites in four Beijing wastewater treatment plants

Four Beijing wastewater treatment plants (WWTPs) were selected to investigate behaviours of nonylphenol polyethoxylates and their metabolites in different wastewater treatment processes. The results showed that the total concentrations of nonylphenolic compounds in the influents of the four WWTPs ranged from 0.115 to 0.347 mumol/L, as well as their removal efficiencies ranging from 75.7% to 90.8%. Both influent concentrations and removal efficiencies of nonylphenol polyethoxylates were correlated to seasons as follows: higher in the summer than in the winter, and influent concentrations were lower during the rain weather. The analysis revealed that 21.8-47.6% of nonylphenol polyethoxylates and their metabolites entering WWTPs were released via effluents and excess sludge, leaving a great part of them for biodegradation. Nonylphenol and short-chain nonylphenol polyethoxylates were disposed to the environment mainly via sewage sludge, while carboxylated nonylphenol polyethoxylates were the most abundant group of nonylphenol polyethoxylates in effluents.