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Aflatoxins are toxic and carcinogenic secondary metabolites produced byAspergillus flavusandAspergillus parasiticus. Strains ofA. flavusthat are non-aflatoxigenic (i.e., incapable of secreting aflatoxins) have proven effective in controlling contamination by these aflatoxin producing species in the field. In the present study, a non-aflatoxigenicA. flavusstrain, GD-3, was isolated from a peanut field in Guangdong Province, China. Polymerase chain reaction (PCR) analysis showed that 12 aflatoxin biosynthesis genes (aflT, pksA, nor-1, fas-2, fas-1, aflR, aflJ, adhA, estA, norA, ver-1 and verA) were deleted in GD-3. Co-inoculation with a toxigenic strain, GD-15, at the ratio of 1:10, 1:1 or 10:1 (GD-3:GD-15), showed that GD-3 was capable of reducing detectable aflatoxin levels on three different substrates. This reduction ranged from 33% to 99% and correlated with competitor ratio. These results demonstrated that GD-3 was successful at reducing aflatoxin contamination and showed promise as a potential agent of biocontrol for local farmers. [ABSTRACT FROM PUBLISHER]

Abstract: We used markers based on inter-simple sequence repeats (ISSR) to examine the genetic diversity of Aspergillus flavus from peanut-cropped soils in China. Of the 100 primers, 22 primers produced clear and reproducible ISSR bands, and the di-nucleotide accounted for 73% of those primers. The size of DNA fragments ranged from 100 to 2000 bp. The primer UBC 834 produced the largest number of polymorphic bands (10), followed by UBC 809, UBC 817, UBC 895, and UBC 899, which all amplified 7 polymorphic bands. Using the five primers, the tested strains were clearly separated based on genetic similarity coefficients (GSC). The range of GSC was from 0.59 to 0.90. In unweighted pair-group method with arithmetic averages (UPGMA) analysis, the A. flavus samples grouped in five clusters. The study showed that the ISSR technology is an effective molecular approach for studying diversity of A. flavus from peanut-cropped soils in China. [Copyright &y& Elsevier]

An in-depth understanding of the soil nutrient status and balance relationship can help the effective recovery and management of alpine degraded meadows. In order to study the balance relationship among soil carbon, nitrogen, and phosphorus nutrients during the heavy degradation stage of meadows, field sampling and investigation, indoor analysis, and mathematical statistics were used to explore the characteristics and driving factors of changes in soil carbon, nitrogen, and phosphorus content, storage, and ecological stoichiometry during the heavy degradation stage of alpine meadows in the Sanjiangyuan region. The results showed that in the heavy degradation stage, miscellaneous grass plants occupied absolute dominance, soil C∶N∶P was approximately 32.83∶3.87∶0.67, and there was certain nitrogen limitation. The coefficients of variation of soil carbon, nitrogen, and phosphorus content were in the following order： organic carbon （1.09） > total nitrogen （0.63） > total phosphorus （0.29）. The organic carbon content and the carbon and nitrogen ratio showed a significant linear decreasing trend with the increase in the grassland degradation index （GDI）, while the total phosphorus content and organic carbon storage showed a significant non-linear change, in which the total phosphorus content showed a significant gentle U-shaped distribution, and the organic carbon storage decreased more gently at the beginning of the heavy degradation stage and then decreased sharply when the GDI was 57.9. The results of Mantel correlation analysis showed that the soil carbon to nitrogen ratio, carbon to phosphorus ratio, and nitrogen to phosphorus ratio showed significant correlation with organic carbon content and storage and total nitrogen storage. The results of structural equation modeling indicated that soil water content had direct effects as well as indirect through vegetation factors, soil carbon, nitrogen, and phosphorus ecological stoichiometry ratios, and soil water content and vegetation factors （height, cover, and biomass） were key environmental factors affecting soil ecological stoichiometry. The research results can provide scientific basis and practical guidance for the restoration of heavily degraded grassland in alpine meadows.

To clarify the regulating effect of vegetation and soil factors on microbial communities in the alpine steppe under degradation on the Qinghai-Xizang Plateau, the alpine steppe in the Sanjiangyuan area of the Qinghai-Tibet Plateau was chosen. We analyzed the differences in vegetation and soil factors in different stages of degradation （non-degradation, moderate degradation, and severe degradation） and detected the variations in microbial community characteristics in the alpine steppe under different degradation stages using high-throughput sequencing technology. Eventually, redundancy analysis （RDA） and multiple regression matrixes （MRM） based on the similarity or dissimilarity matrix were used to identify key environmental factors regulating microbial （bacterial and fungal） community changes under degradation. The results showed that the degradation of the alpine steppe significantly changed the community coverage, height, biomass, and important value of graminae； significantly reduced the contents of soil organic matter, total nitrogen, total phosphorus, and silt； and increased the soil bulk density and sand content. Degradation did not change the composition of bacteria and fungi, but their composition proportions changed and also resulted in the loss of microbial richness （Chao1 index and Richness index） but did not significantly change the microbial diversity （Shannon index）. With the occurrence of degradation, the vegetation characteristics, soil physicochemical properties, and microbial diversity showed a consistent change trend. Combined with the characteristics of the network topology changes （the number of nodes and clustering coefficient significantly decreased）, it was found that degradation of the alpine steppe led to the decline of interspecies interactions, decentralization of network, and homogenization of microorganisms, but the cooperation relations among the species were maintained （positive correlation connections accounted for more than 90% in all degradation stages）. Under the alpine steppe degradation, the vegetation-soil interaction had the greatest effect on soil bacterial community, whereas soil physicochemical properties had the greatest influence on soil fungal community. Specifically, vegetation community height, biomass, and soil bulk density were the mutual factors regulating soil microorganisms, whereas the vegetation Simpson index, important value of graminae, soil total phosphorus, total potassium, and silt content were the unique factors affecting the soil bacterial community, and soil pH and total nitrogen content were the particular factors affecting the soil fungal community.

Objectives: This study aimed to investigate the metastatic rate of circumflex iliac node distal to the external iliac node (CINDEIN) and its associations with clinicopathological factors in patients with stage IA to IIA cervical cancer to determine whether dissection of CINDEIN had a role in surgery of these patients., Methods: Six hundred thirty-three patients with the International Federation of Gynecology and Obstetrics stage IA to IIA cervical cancer who underwent radical hysterectomy and pelvic lymphadenectomy were retrospectively reviewed. The metastatic rate and distribution of the pelvic lymph nodes (PLNs) and CINDEINs were analyzed., Results: The PLN metastatic rate was 25.6% (162 of 633 patients). Sixteen of 162 node-positive patients had CINDEIN metastases. Only 1 patient without PLN metastases had positive CINDEIN nodes. Univariate analysis revealed that other PLNs (including lymph nodes collected from obturator, external iliac, and internal iliac regions) and lymph vascular space involvement were the risk factors of CINDEIN metastases (P < 0.05). Other PLN metastasis (odds ratio, 50.6; 95% confidence interval, 6.6-386.7) was an independent risk factor for metastasis to CINDEIN by binary logistic regression analysis., Conclusions: Circumflex iliac node distal to the external iliac node metastases seemed to occur secondarily to widespread PLN metastases. In early stage cervical cancer, removal of the CINDEIN as a routine surgical procedure might be omitted to reduce operation time and minimize surgical morbidity.

Surgical decision making for femoral neck fractures is currently based on factors such as patient age, fracture type, and medical condition, lacking a quantitative standard. The treatment protocol based on such qualitative assessment has poor operability, greatly affected by the surgeon's subjective factors. As a result, a quantitative score system (QSS) focusing on 5 factors--age, fracture type, bone mineral density, activities of daily living, and medical comorbidities--with a total score of 25 is designed to deal with adult femoral neck fractures. The higher the score, the worse the patient's physiological condition. According to our clinical experience, patients with 1 to 11 points should be treated with internal fixation; patients with 12 to 17 points with total hip arthroplasty (THA), and patients with 18 to 22 points with hemiarthroplasty. Patients with 22 to 25 points should be treated with internal fixation due to the high surgical risk of arthroplasty caused by poor physiological condition. Three hundred seventy-five adult femoral neck fractures were treated on the basis of QSS for this 2-year prospective study. Of these, 242 were treated with low-score internal fixation, 60 with THA, 55 with hemiarthroplasty, and 18 with high-score internal fixation. The revision rates 2 years postoperatively in the low-score internal fixation, THA, and hemiarthroplasty groups were 15.3%, 5.0%, and 5.5%, respectively, which were lower than those from a meta-analysis (internal fixation, 35%; THA, 16%). This QSS helps surgical decision making regarding the treatment choice for adult patients with femoral neck fractures, and good results in preliminary clinical practice have been achieved., (Copyright 2012, SLACK Incorporated.)

Integrated weighted clustering method was applied to plan the monitoring points for agricultural products security. Definite amounts of key monitoring sampling points were mined out from enormous monitoring objects to make the fewer monitoring sampling points cover the product categories, yields, and regions as more as possible. Among the 10172 agricultural products security enterprises all over the China, 2.46% of them were selected. The tested categories, yields, and regions of agricultural safety products covered 32.71%, 44.29%, and 75% of the total, and their coverage increased by 2.80%, 10.85%, 5.56%, respectively, compared with that by using conventional monitoring and management methods, which suggested that it could be more effective to apply integrated weighted clustering method in setting the monitoring points for agricultural products security.

Massive numbers of palm civets were culled to remove sources for the reemergence of severe acute respiratory syndrome (SARS) in Guangdong Province, China, in January 2004, following SARS coronavirus detection in market animals. The virus was identified in all 91 palm civets and 15 raccoon dogs of animal market origin sampled prior to culling, but not in 1,107 palm civets later sampled at 25 farms, spread over 12 provinces, which were claimed to be the source of traded animals. Twenty-seven novel signature variation residues (SNVs) were identified on the spike gene and were analyzed for their phylogenetic relationships, based on 17 sequences obtained from animals in our study and from other published studies. Analysis indicated that the virus in palm civets at the live-animal market had evolved to infect humans. The evolutionary starting point was a prototype group consisting of three viral sequences of animal origin. Initially, seven SNV sites caused six amino acid changes, at positions 147, 228, 240, 479, 821, and 1080 of the spike protein, to generate low-pathogenicity viruses. One of these was linked to the first SARS patient in the 2003-2004 period. A further 14 SNVs caused 11 amino acid residue changes, at positions 360, 462, 472, 480, 487, 609, 613, 665, 743, 765, and 1163. The resulting high-pathogenicity groups were responsible for infections during the so-called early-phase epidemic of 2003. Finally, the remaining six SNVs caused four amino acid changes, at positions 227, 244, 344, and 778, which resulted in the group of viruses responsible for the global epidemic.