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Background: Embryonic Stem Cells (ESCs) can differentiate into cardiomyocytes (CMs) in vitro but the differentiation level from ESCs is low. Here we describe a simple co-culture model by commercially available Millicell™ hanging cell culture inserts to control the long-term differentiation of ESCs into CMs. Methodology/Principal Findings: Mouse ESCs were cultured in hanging drops to form embryoid bodies (EBs) and treated with 0.1 mmol/L ascorbic acid to induce the differentiation of ESCs into CMs. In the indirect co-culture system, EBs were co-cultured with epidermal keratinocytes (EKs) or neonatal CMs (NCMs) by the hanging cell culture inserts (PET membranes with 1 mm pores). The molecular expressions and functional properties of ESC-derived CMs in prolonged culture course were evaluated. During time course of ESC differentiation, the percentages of EBs with contracting areas in NCMs co-culture were significantly higher than that without co-culture or in EKs co-culture. The functional maintenance of ESC-derived CMs were more prominent in NCMs co-culture model. Conclusions/Significance: These results indicate that NCMs co-culture promote ESC differentiation and has a further effect on cell growth and differentiation. We assume that the improvement of the differentiating efficiency of ESCs into CMs in the co-culture system do not result from the effect of co-culture directly on cell differentiation, but rather by signaling effects that influence the cells in proliferation and long-term function maintenance. [ABSTRACT FROM AUTHOR]

Cardiac hypertrophy is an independent predictor of cardiovascular morbidity and mortality. In recent years, evidences suggest that high-mobility group box 1 (HMGB1) protein, an inflammatory cytokine, participates in cardiac remodeling; however, the involvement of HMGB1 in the pathogenesis of cardiac hypertrophy remains unknown. The aim of this study was to investigate whether HMGB1 is sufficient to induce cardiomyocyte hypertrophy and to identify the possible mechanisms underlying the hypertrophic response. Cardiomyocytes isolated from 1-day-old Sprague-Dawley rats were treated with recombinant HMGB1, at concentrations ranging from 50 ng/mL to 200 ng/mL. After 24 hours, cardiomyocytes were processed for the evaluation of atrial natriuretic peptide (ANP) and calcineurin A expression. Western blot and real-time RT-PCR was used to detect protein and mRNA expression levels, respectively. The activity of calcineurin was also evaluated using a biochemical enzyme assay. HMGB1 induced cardiomyocyte hypertrophy, characterized by enhanced expression of ANP, and increased protein synthesis. Meanwhile, increased calcineurin activity and calcineurin A protein expression were observed in cardiomyocytes preconditioned with HMGB1. Furthermore, cyclosporin A pretreatment partially inhibited theHMGB1-induced cardiomyocyte hypertrophy. Our findings suggest that HMGB1 leads to cardiac hypertrophy, at least in part through activating calcineurin. [ABSTRACT FROM AUTHOR]

FeAl intermetallic compound coating was prepared by cold spraying using a mechanically alloyed Fe(Al) alloy powder followed by post-spray annealing at 950 °C. The high-temperature abrasive wear test was carried out for the FeAl coating at a temperature range from room temperature to 800 °C. The high-temperature abrasive wear of a heat-resistant stainless steel 2520 was performed for comparison. It was observed that the abrasive wear weight loss of FeAl coating was proportional to wear cycles in terms of sample revolutions at the tested temperatures. It was found that with the increase of the test temperature higher than 400 °C, the wear rate of cold-sprayed FeAl coating decreased with the increase of test temperature, while the wear rate of the heat-resistant steel increased significantly. The results indicate that the high-temperature abrasive wear resistance of the cold-sprayed FeAl intermetallic coating increased with the increase of the wear temperature in a temperature range from 400 to 800 °C. The wear resistance of cold-sprayed FeAl coating was higher than that of heat-resistant 2520 stainless steel under 800 °C by a factor of 3. [ABSTRACT FROM AUTHOR]

The article looks at the study conducted on larvae of Spodoptera litura (S. litura) to determine the effects of temperature and food on its growth, development and survival. It discusses differential development of larvae and oviposition by females of S. litura depending on different host plants including tobacco, Chinese cabbage, cowpea and sweet potato. The article reflects on the results of the study that states food of larvae directly affects its pupae size and weight.

With the purpose of assessing the environmental impacts and benefits of the current municipal solid waste management system and two modified systems, EASEWASTE, a life-cycle-based model, was used to evaluate the waste system of Hangzhou city in China. An integrated model was established, including waste generation, collection, transportation, treatment, disposal and accompanying external processes. The results showed that CH4 released from landfilling was the primary pollutant contributing to global warming, and HCl and NH3 from incineration contributed most to acidification. Material recycling and incineration with energy recovery were important because of the induced savings in material production based on virgin materials and in energy production based on coal combustion. A modified system in which waste is transported to the nearest incinerators would be relatively better than the current system, mainly due to the decrease of pollution from landfilled waste and the increase in energy production from waste avoiding energy production by traditional power plants. A ban on free plastic bags for shopping was shown to reduce most environmental impacts due to saved oil resources and other materials used in producing the plastic bags. Sensitivity analysis confirmed the robustness of the results. LCA methodology and a model like EASEWASTE are very suitable for evaluating the overall environmental consequences, and can be used for decision support and strategic planning in developing countries such as China where pollution control has become increasingly important with the rapid increase of waste generation as well as the increasing public awareness of environmental protection. [ABSTRACT FROM AUTHOR]

Background: Evidence has shown that autoantibodies against M2 muscarinic acetylcholine receptors may play a role in the development of atrial fibrillation. The goal of this study was to evaluate the effects of anti-M2 receptor autoantibodies on rabbit atria in vivo. Methods: Rabbits were immunized monthly with a synthetic peptide corresponding to the M2 receptor. The atrial electrophysiology of the isolated perfused rabbit hearts was studied. Western blots and RT-PCR were performed to determine the expression of the atrial muscarinic receptor and the acetylcholine-activated potassium channel. Atrial tissue was stained with Masson’s trichrome stain for fibrosis detection. Results: Autoantibodies were persistently detected in immunized rabbits. M2 rabbits showed a significantly shorter atrial effective refractory period and a longer intra-atrial activation time than control rabbits. Electrical stimuli induced a significantly larger number of repetitive atrial responses in M2 rabbits. The protein levels of the M2 receptor and GIRK4 were upregulated in M2 rabbits. The mRNA levels of GIRK1 and GIRK4 were also upregulated. Histological examination revealed significantly increased diffuse fibrotic deposition in M2 rabbit atria compared with control rabbits. Conclusion: The M2 receptor autoantibody-positive rabbits showed altered atrial electrophysiology, overexpression of the M2 receptor-IK,ACh pathway and atrial fibrosis, which indicates that the autoantibodies against M2 receptors may participate in the induction and perpetuation of atrial fibrillation. Copyright © 2008 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Flueggea virosa is a tropical plant of the Phyllanthaceae family, which has high medicinal value. Here, we report and characterize the complete plastome of F. virosa. The complete plastome is 154,961 bp in length and contains the typical structure and gene content of angiosperm plastome, including two inverted repeat (IR) regions of 27,575 bp, a large single-copy (LSC) region of 83,397 bp and a small single-copy (SSC) region of 16,414 bp. The plastome contains 130 genes, consisting of 80 unique proteincoding genes, 30 unique tRNA gene, 4 unique rRNA genes (5S rRNA, 4.5S rRNA, 23S rRNA and 16S rRNA). The overall A/T content in the plastome of F. virosa is 63.10%. The complete plastome sequence of F. virosa will provide a useful resource for the conservation genetics of this species as well as for phylogenetic studies in Phyllanthaceae. [ABSTRACT FROM AUTHOR]

Microbial oil has been gaining considerable attention from researchers recently as renewable and ecofriendly oil and its potential as feedstock for food industry and biodiesel industry. In this context, we have earlier demonstrated production of microbial oil and exopolysaccharide (EPS) from the yeast Sporidiobolus pararoseus JD-2. In this study, we explored increasing its production by optimizing the culture condition and nutrition. As expected, culture temperature and dissolved oxygen (DO) are the contributing factors for co-producing microbial oil and EPS, in which 28℃ and lower quantum (i.e., 30 mL/500 mL) show the best conditions in shake-flasks fermentation. By contrast, the initial pH from 4 to 8 has no obvious effect on producing microbial oil and EPS. In addition, the culture nutrition (i.e., carbon/nitrogen source) were also discussed, and indicating that 20 g/L of corn steep liquor and 60 g/L of glucose are beneficial to produce microbial oil and EPS (i.e., 34.1±1.2 g/L and 11.5±0.2 g/L, respectively). Meanwhile, the residue glucose should be maintained at 20 g/L, in which the highest production of microbial oil and EPS was obtained (i.e., 34.6±1.7 g/L and 11.7±0.8 g/L, respectively). The biomass, microbial oil and EPS were further increased during optimizing the DO level, which reached to 67.8±2.1 g/L, 34.7±0.6 g/L and 11.8±0.5 g/L during maintaining DO level at 20-30%, respectively. The results suggest that appropriate culture condition and nutrition considerably improve the fermentation performance of S. pararoseus JD-2 and significantly increase co-production of microbial oil and EPS (by 11.2 and 8.3%, respectively) compared to the un-optimized fermentation. [ABSTRACT FROM AUTHOR]

A simple uniaxial oedometric system is developed to test the elastic modulus of granular materials. The stress–strain relationship is first measured under conditions of uniaxial compression with additional lateral stress and strain, then the elastic modulus of the material is determined by the linear fitting method. It is found that the modulus is positively correlated to the grain size and negatively correlated to the container size. Arching and dragging are revealed to be the mechanism of such correlations by using the digital image correlation method and the pressure film technology based on the statistical method. [ABSTRACT FROM AUTHOR]

The Treponema denticola surface protease complex, consisting of PrtP protease (dentilisin) and two auxiliary polypeptides (PrcA1 and PrcA2), is believed to contribute to periodontal disease by degrading extracellular matrix components and disrupting host intercellular signaling. Previously, we showed that transcription of the protease operon initiates upstream of TDE0760 (herein designated prcB), the open reading frame immediately 5' of prcA-prtP. The prcB gene is conserved in T. denticola strains. PrcB localizes to the detergent phase of Triton X-114 cell surface extracts and migrates as a 22-kDa polypeptide, in contrast to the predicted 17-kDa cytoplasmic protein encoded in the annotated T. denticola genome. Consistent with this observation, the PrcB N terminus is unavailable for Edman sequencing, suggesting that it is acylated. Nonpolar deletion of prcB in T. denticola showed that PrcB is required for production of PrtP protease activity, including native PrtP cleavage of PrcA to PrcA1 and PrcA2. A 6xHis-tagged PrcB protein coimmunoprecipitates with native PrtP, using either anti-PrtP or anti-His-tag antibodies, and recombinant PrtP copurifies with PrcB-6xHis in nickel affinity chromatography. Taken together, these data are consistent with identification of PrcB as a PrtP-binding lipoprotein that likely stabilizes the PrtP polypeptide during localization to the outer membrane. [ABSTRACT FROM AUTHOR]

Objective To explore the effects of Colla corii asini (CCA) (common name E’jiao) on lung function and pathological injury of the lung tissue in rats with chronic obstructive pulmonary disease (COPD). Methods Twenty-five rats were randomly divided into the control group, COPD model group and treatment group with low, medium and high-doses of CCA (1, 2, 4 g/kg), with 5 rats in each group. The COPD model group and treatment groups were modeled by cigarette smoke exposure with a concentration of (1 100±10)mg/m3 once a day, 90 minutes each time, for 48 consecutive weeks. After the end of the next day, the CCA groups were given by daily oral gavage treatment for 28 days. Lung function was detected by animal lung function instrument and the pathological changes of the lung tissue were assessed by HE staining and microscopy. Results Compared with the control group, TV, EV, Te, RT, EEP and Penh were significantly increased in the COPD model group(P＜0.05), while PEF, PIF, MV, EF50 and f(B) were significantly decreased (P＜0.05). Inflammation and pathological changes of emphysema were observed, and lung tissue lesions were aggravated. Compared with the COPD model group, Te, RT and Penh were significantly reduced in the high-dose CCA group (P＜0.05), while MV, PIF and EF50 were significantly higher (P＜0.05). Less infiltration of inflammatory cells, less alveolar expansion and fewer pulmonary bullae were observed in high-dose CCA-treated rats. The degree of emphysema was reduced, and pathological damage to lung tissue was clearly alleviated. Conclusions CCA improves lung function and alleviates the inflammatory response of the lung tissue in COPD rats.

Among various types of brain computer interfaces (BCIs), steady state visually evoked potential (SSVEP) based BCIs can provide high information transfer rate (ITR), however the users could suffer serious fatigue that may induce discomfort, health hazards and deterioration of system performance. To overcome the fatigue obstacle, the first step is to detect the fatigue accurately, reliably and quickly. This paper proposes an approach based on the wavelet entropy of the measured EEG to fatigue detection in real time when using an SSVEP-BCI. Specifically, the wavelet analysis is first applied to the EEG, resulting in the approximation and detail components at different levels. The sample entropy values of these components are then calculated to generate features for classification. Experimental results identified the entropy of the lower frequency components (0 – 4.6875Hz) as the most important feature. The proposed wavelet entropy improved the fatigue detection accuracy to 87.7% from 65.1% by the traditional entropy method, when distinguishing subjects’ mental states between alert (before task) and fatigue (after task). Furthermore, the detection accuracy based on the state of art multiple conventional fatigue indices can be improved from 91.9% to 96.5% by replacing the delta band amplitude with the new wavelet entropy feature.

Diabetic osteoporosis (DOP) is one of the complications of diabetes, with high morbidity, and high disability rate. Here, we established a diabetic rat model and administered lycopene to observe its effect on DOP. Our results showed that ten weeks lycopene treatment lowered blood glucose, improved diabetic induced polydipsia, overeating and body weight loss. Lycopene treatment also enhanced bone mineral density, restored bone mechanical and bone Micro-CT parameters of diabetic rats. Subsequently, lycopene decreased serum inflammatory cytokines levels and increased serum anti-oxidant indicators levels. Moreover, lycopene reduced the number of bone marrow adipocytes, and osteoclasts numbers of diabetic rats. The serum bone turnover markers levels were down-regulated after lycopene treatment. Meanwhile, the bone and serum OPG, RUNX 2 expression levels were up-regulated by lycopene in diabetic rats, and the OPG/RANKL ratio was also up-regulated. This study showed that lycopene could ameliorate diabetic induced bone loss via anti-inflammatory, anti-oxidation, and increasing OPG/RANKL ratio in diabetic rats. Lycopene could be used for nutritional intervention in patients with diabetic osteoporosis.

Antibiotic resistance genes (ARGs), prevalent across multiple environmental media, threaten human health worldwide and are considered emerging environmental contaminants. Earthworm gut, a niche for bacteria to survive, represents a potential reservoir for ARGs in soil. However, the compositions of ARGs in the earthworm gut microbiota remain elusive, especially under field conditions. In this study, we applied high-throughput quantitative PCR to profile the ARGs in the gut microbiota of earthworms after chronic exposure to fertilizers. To elucidate the factors that impact the ARGs composition, the bacterial community of gut microbiota, mobile genetic elements (MGEs), soil (nutrients, heavy metals, and antibiotics) and the properties of gut content (pH and nutrients) were analyzed. A total of 98 subtypes among 9 major types of ARGs, and 3 different MGEs were detected in the gut microbiota of earthworms. Organic fertilizer (sewage sludge and chicken manure) application significantly increased the diversity and abundance of ARGs. Of the 1123 identified operational taxonomic units (OTUs) at 97% similarity cutoff, most of them were assigned to Firmicutes (55.5%) and Proteobacteria (33.6%) in earthworm gut microbiota. Long-term organic fertilization slightly changed the microbiota composition, but did not impact the diversity. Partial redundancy analysis (pRDA) revealed that bacterial community, combined with environmental factors (soil and gut content properties) and MGEs, explained 72% of the variations of ARGs in the earthworm gut. Furthermore, the co-occurrence pattern between ARGs and MGEs indicated that horizontal gene transfer via MGEs may occur in the earthworm gut. These findings improve the current understanding of the dynamics of soil fauna-associated ARGs and the gut microbiota of earthworms may be an underappreciated hotspot for ARGs in the environment. Keywords: Antibiotic resistome, Gut microbiota, Soil fauna, Sewage sludge, Chicken manure

A prompt gamma ray neutron activation analysis detection system was developed to detect the heavy metals in sediments by using an 241 Am-Be neutron source and BGO detector. The samples containing cadmium and mercury were used to test the performance of setup. The linear relationship between prompt gamma ray counts and the concentrations was studied. The results showed the counts of the prompt gamma rays from cadmium do not increase linearly with its concentrations, while the prompt gamma ray counts from Hg vary nearly linearly with the concentrations, due to the neutron self-shielding. Then a method was used to correct the effect and the non-linearly response was restored after the correction. And the minimum detectable concentration of Cd and Hg were 52.8 (at 8.484 MeV) and 81.6 (at 5.967 MeV) ppm, respectively. [ABSTRACT FROM AUTHOR]

This study was conducted to assess availability, phytotoxicity and bioaccumulation of lead (Pb) to ryegrass (Lolium perenne L.) and millet (Echinochloa crusgalli) based on the 0.1 mol/L Ca(NO3), extraction. Effect of soil properties on availability, phytotoxicity and bioaccumulation of Pb to the two plants was also evaluated. Five soils with pH values varying from 3.8 to 7.3, organic carbon (OC) contents from 0.7% to 2.4%, and clay contents from 11.6% to 35.6% were selected. Soils were spiked with Pb to achieve a range of concentrations: 250, 500, 1000, 3000 and 5000 mg/kg. Pb availability in the spiked soils was estimated by extracting soil with 0.1 mol/L Ca(NO3)2. The results indicate that plants yield decreased with decreasing soil pH and increased with increasing soil clay and OC content. Negative relationship between available Pb and the relative dry matter growth (RDMG) of the two plants were significantly related. Available Pb used to assess EC20 (20% effective concentration) and EC50 (50% effective concentration) of millet was 119 and 300 mg/kg, respectively. Available Pb used to assess EC20 and ECs, of ryegrass was 63 and 157 mg/kg, respectively. Bioaccumulation, expressed as bioconcentration factors of Pb, was inversely related to soil pH, soil OC and clay content. Strong relationships were found between available lead and uptake by the two plants (i was 0.92 and 0.95 respectively). In general, 0.1 mol/L Ca(NO3)2 available Pb may be used to assess the availability, phytotoxicity and bioaccumulation of lead to the two plants tested.