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Soil organic matter (SOM) content is one of the most important indicators of the sustainability of soil. To maintain sustainable soil utilization and management in fragile Hani terraced field, it is meaningful to investigate the effects of topography and land use type on SOM content. Descriptive statistics and geostatistics were used to analyze the data and the kriging method was applied to map the spatial patterns of SOM content. The results showed that the mean SOM content was 32.76 g/kg, with a variation coefficient of 40%. The SOM content was affected by elevation and land use type. As the increase of elevation, the SOM content in Hani terraced field also increased obviously. The SOM content in tea garden, which is almost at high elevation, was the highest in all six land use types, and the SOM content decreased in a following sequence: tea garden > paddy field > corn field > banana garden > cassava field > sugarcane field. In addition, at the same elevation, the paddy field had the highest SOM content compared with other land use types. All these results demonstrate that paddy field is the most efficient and suitable land use type for SOM conservation at high, middle or low elevations in the fragile Hani terraced field. In order to protect soil quality and maintain the sustainable agricultural development, it is necessary to maintain or even to enlarge the area of paddy field in Yuanyang county, Yunnan Province, China.

The aim of the present study was to explore the role of ovarian cancer G protein-coupled receptor 1 (OGR1) in osteoclast differentiation and activity induced by extracellular acid. The impact of extracellular acidification on osteoclasts was investigated. Briefly, osteoclasts were generated from RAW 264.7 cells using 100 ng/ml receptor activator of nuclear factor-κB ligand in cell culture media at pH 6.8 or 7.4. Tartrate-resistant acid phosphatase (TRAP) staining and the bone resorption pit assay were used to detect the effects of extracellular acid on the number and absorptive capacity of osteoclasts. Intracellular Ca2+ levels were analyzed using laser scanning confocal microscopy. Reverse transcription-quantitative PCR was used to detect the expression levels of genes associated with osteoclast formation and bone erosion. The role of OGR1 in the acid-stimulated formation and bone resorption of osteoclasts was also investigated. The results showed that in the pH 6.8 medium group the number of osteoclasts was 511.2±54.72 and the area of bone absorption was 4,184.88±277.14 µm2; both were significantly higher than those in the pH 7.4 medium group (all P<0.01). Inhibition of OGR1 using copper ion (Cu2+) reduced the number of osteoclasts and the area of bone resorption in the pH 6.8 medium group (all P<0.05). Furthermore, extracellular acid (pH 6.8) was able to induce a transient increase of Ca2+ levels in osteoclasts; however, inhibition of OGR1 using Cu2+ effectively attenuated the acid-induced increase of Ca2+ in osteoclasts. In addition, the elevation in Ca2+ levels was inhibited when BAPTA, a cytoplasmic Ca2+ chelator with cellular permeability, was added to the cells; however, the extracellular Ca2+-chelating agent ethylene glycol tetraacetic acid did not inhibit the acid-stimulated increase in Ca2+. Treatment with the phospholipase C inhibitor U73122 also inhibited the acid-stimulated increase of Ca2+ in osteoclasts. Furthermore, the mRNA expression levels of TRAP, matrix metalloproteinase-9, osteoclast-related receptor, nuclear factor-activated T cell 1 (NFATc1), cathepsin K and integrin β3 were elevated in the pH 6.8 medium group compared with those in the pH 7.4 medium group (all P<0.05). By contrast, the inhibition of OGR1 using Cu2+ partially reduced the effects of the acidic environment on osteoclast differentiation and activity-related gene expression (all P<0.05). In addition, the mRNA and protein expression levels of calcineurin were increased in osteoclasts in the pH 6.8 group compared with those in the pH 7.4 group (P<0.05), whereas blocking OGR1 suppressed the expression of acid-induced calcineurin. The mRNA expression levels of NFATc1 in osteoclasts were also increased in the pH 6.8 medium group compared with those in the pH 7.4 medium group (P<0.05). By contrast, the specific calcineurin inhibitor cyclosporine A significantly inhibited the acid-induced expression of NFATc1 in osteoclasts. In conclusion, the present study revealed that extracellular acidification may increase osteoclast differentiation and bone resorption activity. Furthermore, OGR1-mediated Ca2+ elevation could have a crucial role in osteoclasts by regulating the Ca2+-calcineurin-NFATc1 signaling pathway and downstream signaling. [ABSTRACT FROM AUTHOR]

Well-dispersed mesoporous SiO 2 colloidal spheres (MSCSs) were prepared with hexadecyltrimethyl ammonium phosphomolybdate (M-6) as template. The MSCSs were characterized by scanning electron microscopy, transmission electron microscopy, X-ray powder diffraction, and Fourier transform infrared spectroscopy, etc. The diameter and the uniform pore size of the MSCSs are ∼ 200 nm and ∼ 2.85 nm, respectively. By rational tuning the synthesis conditions such as the concentration of M-6, the volume ratio of water to ethanol, the amount of tetraethoxysilane, etc., the morphology, size and dispersity of the SiO 2 products can be easily controlled. The formation mechanism of the as-prepared MSCSs was also proposed. Treated with sulfuric acid, the resulted MSCSs exhibited excellent catalytic activity in the synthesis of biodiesel via the esterification of long-chain free fatty acids. [ABSTRACT FROM AUTHOR]

PURPOSE: To assess the bone density of dental implant sites using spiral CT and simplant software, and classify, them by Lekholm and Zarb grouping. METHODS: 53 patients' jaw bone were scanned by spiral CT, the scanned images were reconstructed by the Simplant software. The bone density of 136 designed implant sites was measured and the results were recorded using Hounsfield units (HU).The data was analyzed with SPSSll.0 software package for Mann- Whitney U test, and classified by Lekholm and Zarb grouping. RESULTS: The mean bone density in all implant sites was (714.66±273.72) HU. The anterior mandible mean bone density was (962.96±92.21)HU > anterior maxilla, (786.15± 188.74) HU > posterior mandible, (785.79±290.91) HU > posterior maxilla, (569.67±244.34)HU. Bone class IV was least in anterior mandible and most in posterior maxilla(P<0.01 ), accounting for 26.5% in all implant sites. CONCLUSIONS: Anterior mandible has the highest mean bone density and posterior maxilla has the lowest mean bone density. There are class I and II/III in most of the implant sites. Spiral CT is a useful tool for determining the bone density, which is important for preoperative design and postoperative assessment. [ABSTRACT FROM AUTHOR]

We determined the complete mitochondrial genome of the oriental armywormMythimna separata(Walker) (Lepidoptera: Noctuidae), which is one of the serious cereal pests in Asia and Australia. The circular genome of 15,332 bp in length contains 37 typical animal mitochondrial genes and a non-coding A + T-rich region. Its gene content and order are typical of lepidopteran mitochondrial genomes described to date. All protein-coding genes (PCGs) start with an ATN codon except forcox1andnad1, which use CGA and TTG as their start codon, respectively. Ten PCGs use complete stop codon TAA, whereas three PCGs end with single T. The A + T-region is located betweenrrnSandtrnMwith a length of 374 bp. The mitochondrial genome sequence benefits future studies of molecular phylogenetics and pest control. [ABSTRACT FROM PUBLISHER]

We determined the complete mitochondrial genome of the common cutwormSpodoptera litura(Lepidoptera: Noctuidae), which is one of the most destructive polyphagous insect pests worldwide. The genome is 15,383 bp in length (GenBank accession number: KF701043) with an A + T content of 81.08%, and contains 37 typical animal mitochondrial genes (13 protein-coding genes, 2 rRNA genes and 22 tRNA genes) with the typical arrangement found in Lepidoptera. All the protein-coding genes (PCGs) start with ATN start codon except forcox1, which begins with CGA. Eight PCGs stop with complete termination codons (TAA or TAG), whereas five PCGs use incomplete stop codon T. The A + T-rich region is located betweenrrnSandtrnMwith a length of 326 bp and an A + T content of 93.87%, and harbors three tandem repeat elements. [ABSTRACT FROM PUBLISHER]

Objective: To discuss the effect of Drynariae Rhizoma's naringin on osteoclasts induced by mouse monocyte RAW264.7., Method: RAW264.7 cells were induced by 100 μg x L(-1) nuclear factor-κB receptor activator ligand (RANKL) and became mature osteoclasts, which were identified through TRAP specific staining and bone resorption. MTT method was sued to screen and inhibit and the highest concentration of osteoclasts. After being cultured with the screened medium containing naringin for 5 days, positive TRAP cell counting and bone absorption area analysis were adopted to observe the effect of naringin on the formation of osteoclast sells and the bone absorption function. The osteoclast proliferation was measured by flow cytometry. The effects of RANK, TRAP, MMP-9, NFATc1 and C-fos mRNA expressions on nuclear factor-κB were detected by RT-PCR., Result: Naringin could inhibit osteoclast differentiation, bone absorption function and proliferation activity of osteoclasts, significantly down-regulate RANK, TRAP, MMP-9 and NFATc1 mRNA expressions in the osteoclast differentiation process, and up-regulate the C-fos mRNA expression., Conclusion: Naringin could inhibit osteoclast differentiation, proliferation and bone absorption function. Its mechanism may be achieved by inhibiting the specific gene expression during the osteoclast differentiation process.

Purpose: To assess the bone density of dental implant sites using spiral CT and simplant software, and classify them by Lekholm and Zarb grouping., Methods: 53 patients' jaw bone were scanned by spiral CT, the scanned images were reconstructed by the Simplant software.The bone density of 136 designed implant sites was measured and the results were recorded using Hounsfield units(HU).The data was analyzed with SPSS11.0 software package for Mann-Whitney U test, and classified by Lekholm and Zarb grouping., Results: The mean bone density in all implant sites was (714.66+/-273.72) HU.The anterior mandible mean bone density was (962.96+/-92.21)HU>anterior maxilla, (786.15+/-188.74) HU>posterior mandible, (785.79+/-290.91) HU>posterior maxilla, (569.67+/-244.34)HU. Bone class IV was least in anterior mandible and most in posterior maxilla(P<0.01), accounting for 26.5% in all implant sites., Conclusions: Anterior mandible has the highest mean bone density and posterior maxilla has the lowest mean bone density. There are class I and II/III in most of the implant sites. Spiral CT is a useful tool for determining the bone density, which is important for preoperative design and postoperative assessment.