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South China has been experiencing very high rate of acid deposition and severe soil acidification in recent decades, which has been proposed to exacerbate the regional ecosystem phosphorus (P) limitation. We conducted a 10-year field experiment of simulated acid deposition to examine how acidification impacts seasonal changes of different soil P fractions in a tropical forest with highly acidic soils in south China. As expected, acid addition significantly increased occluded P pool but reduced the other more labile P pools in the dry season. In the wet season, however, acid addition did not change microbial P, soluble P and labile organic P pools. Acid addition significantly increased exchangeable Al3+ and Fe3+ and the activation of Fe oxides in both seasons. Different from the decline of microbial abundance in the dry season, acid addition increased ectomycorrhizal fungi and its ratio to arbuscular mycorrhiza fungi in the wet season, which significantly stimulated phosphomonoesterase activities and likely promoted the dissolution of occluded P. Our results suggest that, even in already highly acidic soils, the acidification-induced P limitation could be alleviated by stimulating ectomycorrhizal fungi and phosphomonoesterase activities. The differential responses and microbial controls of seasonal soil P transformation revealed here should be implemented into ecosystem biogeochemical model for predicting plant productivity under future acid deposition scenarios.

Biochar application can influence soil nitrogen (N) cycle through biological and abiotic processes. However, studies on comprehensive examination of the effects of biochar application on microbially mediated N‐cycling processes (N mineralization, nitrification, denitrification, and fixation) and soil N fate (i.e., plant N uptake, soil N2O emission, and N leaching) are warranted. Therefore, the aim of this study was to examine the effects of biochar application on soil N transformation, microbial functional gene abundance, enzyme activity, and plant N uptake. To achieve the objective of this study, a meta‐analysis involving 131 peer‐reviewed field experiments was conducted. Results showed that field application of biochar significantly enhanced soil NH4+ and NO3‐ content, N mineralization, nitrification, N2 fixation, and plant N uptake by 5.3%, 3.7%, 15.3%, 48.5%, 14.7%, and 18.3%, respectively, but reduced N2O emissions and N leaching by 14.9% and 10.9%, respectively. Biochar application also increased the abundance of soil denitrifying/nitrifying genes (amoA, narG, nirS/nirK+S, and nosZ), proportion of N2 fixation bacteria, and N‐acetyl‐glucosaminidase activity by 18.6%–87.6%. Soil NO3‐ content was positively correlated with AOA‐amoA abundance, and soil N2O emission was positively correlated with the relative abundance of genes (e.g., amoA, narG, and nirS/nirK) involved in N2O production. Furthermore, long‐term biochar application tended to increase AOB‐amoA and nirK+S abundance, especially soil N2O emission and N leaching. Overall, the findings of this study indicated that biochar application accelerated microbially mediated N‐cycling processes under field conditions, thereby enhancing soil N availability and plant productivity. However, long‐term biochar application may increase N losses. Therefore, future studies should be conducted to examine the effect of long‐term biochar application on the soil N cycle and the underlying microbial mechanisms.

Slow cycling organic matter such as plant lignin components or microbial necromass play important roles in soil organic carbon (SOC) accumulation, but their relatively importance are rarely quantified or have been under debate in forest ecosystems. While the traditional hypothesis holds that low-quality litter inputs generally favor more SOC accumulation by selectively storing recalcitrant lignin components, an emerging hypothesis highlights high-quality litter inputs effectively promoting more SOC formation due to faster microbial decomposition leading to more necromass products. Here, we compiled and analyzed a global database of plant lignin components (lignin phenols as biomarker; 126 individual sties) and microbial necromass (amino sugars as biomarker; 137 individual sties) together with SOC in surface mineral soils across coniferous, broad-leaved and mixed forests that represent different litter-quality inputs. Results showed that amino sugars were insignificant predictor for SOC variations across different forest types. SOC contents increased with lignin phenols, but lignin phenols were significantly higher in broad-leaved and mixed forests than in coniferous forests. Therefore, our findings challenge both traditional and emerging hypotheses, and provide new insights for future research on the mechanisms of SOC formation and stabilization from plant and microbial pathways.

Forests play an essential role in mitigating climate change by sequestering carbon dioxide from the atmosphere. The establishment of mixed plantations is a promising way to store carbon (C) in soil compared with monocultures. However, monoculture forests largely dominate the rapid increase in forest areas in China. To optimize afforestation strategies and maximize the subsequent potential of C sequestration, we conducted a meta-analysis with 427 observations across 176 study sites in China. The goal was to quantify changes in the stocks of soil organic carbon (SOC) in mixed plantations compared with monocultures and to identify the predominant drivers for the stocks of SOC, including geological location, climatic factors, land use history, edaphic properties, plantation age, the inclusion of nitrogen-fixing trees, mixing proportion, and mixed plant types. The results showed that mixed plantations significantly increased the SOC stocks by 12% compared with monocultures, and the mixing proportion should not exceed 55% to produce higher SOC stocks in mixed plantations compared with monoculture. Additionally, mixed plantations in barren land are the most likely to increase the SOC stocks with limited water or low temperatures for growth. Additional measures instead of mixed plantations should be explored to increase SOC stocks in north, central, and northwest China. The data from this study demonstrated the spatiotemporal variability on the storage of SOC driven by mixed trees and has valuable implications for the establishment and management of afforestation.

Biochar may be potentially used as a rhizobial carrier due to its specific chemical compositions and surface properties, but the relationship between these properties and rhizobial survival rate is largely unknown. Here, we analysed the physicochemical characteristics and carrier potential of six types of biochars made from various feedstocks at 600 °C using slow pyrolysis method, and results were compared with conventional carrier material peat. Liquid suspension of Bradyrhziobium japonicum CB1809 was used to inoculate all the carrier materials. Shelf life and survival rate was determined via colony forming unit (CFU) method for up to 90 days under two storage temperature conditions (28 °C and 38 °C). The determined physicochemical characteristics of biochars were categorized into major elements, trace elements, relative ratios, surface morphology, functional groups, and key basic properties; and their interaction to shelf life was analysed using hypothesis-oriented structure equation modelling (path analysis). Results revealed that different types of biochars had different capacity to impact on shelf life due to their different physicochemical properties. Among all biochars pine wood BC was the most suitable carrier with the highest counts of 10.11 Log 10 CFU g

Nano-antibacterial agents can play a critical role in chronic wound management. However, the design of an intelligent nanosystem that can provide both a visual warning of infection and precise sterilization remains a hurdle. Herein, a rod-like porphyrin-based metal-organic framework theranostic nanosystem (Zn-TCPP nanorods) is fabricated via coordination chelation between tetrakis(4-carboxylphenyl)porphyrin and zinc ions. This system can show significant fluorescence activation in response to the local elevated pH shown by chronic wounds, a main indicator of wound infection. Meanwhile, under the guidance of fluorescence imaging, the highly spatiotemporally precise photodynamic inactivation of microorganisms can be carried out without the destruction of surrounding normal cells and nascent cells. The results demonstrated that the Zn-TCPP nanorods were a highly sensitive and reversible probe for sensing alkaline pH levels. Alterations in the fluorescence of the Zn-TCPP nanorods can accurately indicate the infection status and heterogeneity of infection within the wound bed. Under specific light irradiation, the Zn-TCPP nanorods can exterminate 97% of Staphylococcus aureus via the generation of reactive oxygen species (ROS). Assays of extensive wounds demonstrate that the precise fluorescence-imaging-guided suppression of bacterial infection can significantly reduce the mouse mortality rate and accelerate wound healing. This system provides the opportunity for "precision medicine" relating to chronic wounds and some large-area wounds.

To explore the efficiency and safety of laparoscopic anus-conserving operation for ultralow rectal cancer, we retrospectively reviewed 236 patients with ultralow rectal cancer who underwent laparoscopic anus-conserving operation (experimental group, n = 124) or conventional open surgery (control group, n = 112). Operation-related indexes, pathological results of mesentery, incidence rates of postoperative complications, anus preservation rates, anal sphincter controllability after surgery, and survival rates of the first, second, and third years after operation were compared between the two groups. The amount of intraoperative bleeding, first postoperative exhaust time, abdominal drainage, pain score, and hospital stay in the experimental group were significantly less than those in the control group ( P < 0.05). There were no significant differences in the postoperative circumferential resection margin, distal resection margin, number of dissected lymph nodes, successful resection rate, and quality of mesorectum between the two groups ( P > 0.05). The total incidence rate of postoperative complications, anal sphincter controllability, and survival rates after surgery were similar between the two groups ( P > 0.05). The anus preservation rate of the experimental group (84.7%) was significantly higher than that of the control group (69.6%) ( P < 0.05). Laparoscopic anus-conserving operation is effective and safe in treatment of patients with ultralow rectal cancer, which has advantages such as small trauma, less intra-operative bleeding, short hospital stay, rapid recovery, a low incidence rate of postoperative complications, and a high anus-preserving rate, so it is worthy of clinical application.

The objective of this study was to investigate the effects of amendment of different biochars on the physical and hydraulic properties of desert soil. Biochars were produced with woodchip, rice straw, and dairy manure at temperatures of 300 and 700 °C, respectively. Each biochar at 5% (w/w) was mixed with desert soil, and the mixtures were incubated for 120 days. The different biochar treatments greatly reduced soil bulk density and saturated hydraulic conductivity. Especially the rice straw biochar addition resulted in the lowest saturated hydraulic conductivities among the treatments. Biochar addition significantly increased water retention of desert soil at any suction. At the same suction and experimental time, the treatment with the rice straw biochar produced at the lower temperature resulted in higher water content than the other treatments. The biochar additions slightly enhanced formation of soil macro-aggregates in the early experimental time. However, the aggregate contents gradually decreased with time due to the lack of effective binding agents (e.g., soil organic matter and clay minerals). The changes of hydraulic properties of desert soil were attributable to the biochar properties. The higher fine particle content, porosity, and surface hydrophilicity of rice straw biochars were the most beneficial properties to increase soil water retention and to reduce water flow in the desert soil. The improvement of hydraulic properties by biochar addition may provide a potential solution to combat desertification.

Both crizotinib and sunitinib, novel orally-active multikinase inhibitors, exhibit antitumor activity and extend the survival of patients with a malignant tumor. However, some patients may suffer liver injury that can further limit the clinical use of these drugs, however the mechanisms underlying hepatotoxicity are still to be elucidated. Thus, our study was designed to use HepG2 cells in vitro and the ICR mice model in vivo to investigate the mechanisms of hepatotoxicity induced by crizotinib and sunitinib. Male ICR mice were treated orally with crizotinib (70 mg/kg/day) or sunitinib (7.5 mg/kg/day) for four weeks. The results demonstrated that crizotinib and sunitinib caused cytotoxicity in HepG2 cells and chronic liver injury in mice, which were associated with oxidative stress, apoptosis and/or necrosis. Crizotinib- and sunitinib-induced oxidative stress was accompanied by increasing reactive oxygen species and malondialdehyde levels and decreasing the activity of superoxide dismutase and glutathione peroxidase. Notably, the activation of the Kelch-like ECH-associated protein-1/Nuclear factor erythroid-2 related factor 2 signaling pathway was involved in the process of oxidative stress, and partially protected against oxidative stress. Crizotinib and sunitinib induced apoptosis via the mitochondrial pathway, which was characterized by decreasing Bcl2/Bax ratio to dissipate the mitochondrial membrane potential, and increasing apoptotic markers levels. Moreover, the pan-caspase inhibitor Z-VAD-FMK improved the cell viability and alleviated liver damage, which further indicated the presence of apoptosis. Taken together, this study demonstrated that crizotinib- and sunitinib-caused oxidative stress and apoptosis finally impaired hepatic function, which was strongly supported by the histopathological lesions and markedly increased levels of serum alanine aminotransferase, alkaline phosphatase and lactate dehydrogenase.

Aim: Our study aimed at investigating how LINC01133 functions in gastric cancer (GC) progression. Materials & methods: Gain-of-function and loss-of-function approaches were applied to analyze the effects of LINC01133, microRNA-576-5p (miR-576-5p) and somatostatin (SST) on the biological behaviors of GC cells and in tumor-bearing nude mice. Results: GC tissues and cells showed low expression of LINC01133, and LINC01133 overexpression decreased malignant phenotypes of GC cells. Moreover, LINC01133 upregulated SST through binding to miR-576-5p. Overexpressing miR-576-5p or suppressing SST reversed the functions of LINC01133 in biological potentials of GC cells and tumor growth. Conclusion: LINC01133 overexpression may inhibit GC development by downregulation of miR-576-5p and upregulation of SST, which suggests new therapeutic targets for GC.

Background: Colorectal cancer (CRC) is the most common type of gastrointestinal malignant tumour. Colorectal adenocarcinoma (COAD) – the most common type of CRC – is particularly dangerous. The role of the immune system in the development of tumour-associated inflammation and cancer has received increasing attention recently. Methods: In the present study, we compiled the expression profiles of 262 patients with complete follow-up data from The Cancer Genome Atlas (TCGA) database as an experimental group and selected 65 samples from the Gene Expression Omnibus (GEO) dataset (of which 46 samples were with M0) as a verification group. First, we screened the immune T helper 17 (Th17) cells related to the prognosis of COAD. Subsequently, we identified Th17 cells-related hub genes by utilising Weighted Gene Co-expression Network Analysis (WGCNA) and Least Absolute Shrinkage and Selector Operation (LASSO) regression analysis. Six genes associated with the prognosis in patients with COAD were identified, including: KRT23, ULBP2, ASRGL1, SERPINA1, SCIN, and SLC28A2. We constructed a clinical prediction model and analysed its predictive power. Results: The identified hub genes are involved in developing many diseases and closely linked to digestive disorders. Our results suggested that the hub genes could influence the prognosis of COAD by regulating Th17 cells’ infiltration. Conclusions: These newly discovered hub genes contribute to clarifying the mechanisms of COAD development and metastasis. Given that they promote COAD development, they may become new therapeutic targets and biomarkers of COAD.

Circular RNA (circRNA) abnormal expression and regulation are involved in the occurrence and development of a variety of tumors. However, the role of circRNAs still remains unknown in gastrointestinal stromal tumors (GISTs). In the present study, the differential circRNA expression profile of GISTs was screened by human circRNAs chip and verified by qRT-PCR. The circRNA–miRNA–mRNA regulatory network was constructed using the cytoHubba plugin based on the Cytoscape software. Gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses were performed to explore circRNA functions. Six significantly differential circRNAs were also verified in 20 pairs of GISTs and adjacent tissues by qRT-PCR. The result showed that a total of 543 differentially expressed circRNAs were identified in GISTs, of which 242 were up-regulated and 301 were down-regulated. Additionally, the circRNA–miRNA–mRNA network contained six circRNAs, 30 miRNAs, and 308 mRNAs, and the targeted mRNAs were associated with “regulation of biological process,” “intracellular organelle,” “protein binding,” and enriched in Wnt signaling pathway. Furthermore, qRT-PCR demonstrated that hsa_circRNA_061346, hsa_circRNA_103114, and hsa_circRNA_103870 were significantly up-regulated in GISTs (n = 20), and hsa_ circRNA_405324, hsa_circRNA_406821, and hsa_circRNA_000361 were dramatically down-regulated in GISTs (n = 20). In addition, all of these circRNAs were shown to have high diagnostic values, and most of them were significantly associated with tumor size, mitotic figure, and malignant degrees in GISTs (P < 0.05). Therefore, we concluded that circRNAs were abnormally expressed in GISTs, and the circRNA–miRNA–mRNA regulatory network plays an important role in the occurrence and development of GISTs. Also, the identified six candidate circRNAs might be critical circRNAs and may present as potential diagnostic biomarkers for GISTs.

Orchard grass coverage has been widely adopted to increase fruit yield by improving soil fertility. However, the impact of the environment on the changes in soil organic carbon (SOC) stocks consecutive to orchard grass coverage remain poorly quantified at a large scale. The present study aimed to examine the responses of SOC stocks to grass coverage at a soil depth of 0-30 cm in orchards compared to clean tillage. A total of 342 observations across China from 139 peer-reviewed publications were subjected to meta-analysis. Aggregated boosted tree analysis was performed, evaluating the determinants of SOC stocks, such as plant traits (e.g., fruit tree type, grass type, orchard age, and grass age), edaphic variables (e.g., initial SOC and nitrogen concentration, soil pH, and soil clay content), climatic factors (e.g., mean annual precipitation (MAP) and mean annual temperature (MAT)), and management practices (e.g., grass source, grass growing mode, fertilization, grass mowing, placement of mowed residues, and irrigation). On average, orchard grass coverage significantly enhanced SOC stocks by 21.47% (percentage change) compared to clean tillage. Biotic and abiotic factors influenced this increase in SOC stocks following grass coverage in orchards to different extents. Grass age and soil clay content were the main determinants driving the variation in the SOC stocks following grass coverage in orchards. Thus, we propose an efficient way to optimize C sequestration in grass covered orchards, regarding plant traits, climatic factors, edaphic variables, and management practices. Longer than 12 months of surface grass coverage with cultivated grass species in mature deciduous fruit orchards (≥5 years) efficiently increased SOC stocks. This is particularly the case for acidic (pH 6.5) soils with low C content (SOM 15 g kg

The feasibility of using a polymerase chain reaction (PCR)-based label-free DNA sensor for the detection of Helicobacter pylori is investigated. In particular, H. pylori ureC gene, a specific H. pylori nucleic acid sequence, was selected as the target sequence. In the presence of ureC gene, the target DNA could be amplified to dsDNA with much higher detectable levels. After added the SYBR green I (SGI), the sensing system could show high fluorescence. Thus, the target DNA can be detected by monitoring the change of fluorescence intensity of sensing system. The clinical performance of this method was determined by comparing it with another conventional technique urea breath test (UBT). The result also showed good distinguishing ability between negative and positive patient, which was in good agreement with that obtained by the UBT. It suggests that the label-free fluorescence-based method is more suitable for infection confirmation test of H. pylori. This approach offers great potential for simple, sensitive and cost-effective identification of H. pylori infection.

Afforestation made great contributions to ecological benefits across China. Robinia pseudoacacia is widely used in the Grain-for-Green Program. The responses of soil organic carbon (SOC) and soil total nitrogen (STN) to afforestation with R. pseudoacacia on cropland depend on plantation attributes, climatic factors, topographic features, and edaphic variables, thus making a synthesis of these studies necessary for understanding the magnitude and direction of SOC and STN to afforestation and the associated regulating factors. A meta-analysis was employed by compiling data of 1202 paired observations from 94 peer-reviewed publications to depict potential mechanisms of change in SOC and STN stocks following afforestation with R. pseudoacacia on cropland. Afforestation with R. pseudoacacia on cropland, on average, significantly and positively increased SOC and STN stocks. The changes in SOC and STN stocks increased with plantation age and altitude, but decreased with mean annual temperature, slope gradients, soil depth, soil clay content, initial SOC content and initial STN content. Greater accumulation rates of SOC and STN stocks after afforestation were detected in middle canopy density (0.6–0.8) and middle mean annual precipitation (450–550 mm). Among four kinds of biotic and abiotic factors, plantation attributes made greatest contributes to the variance in the response size of SOC and STN stocks. In particular, plantation age was the most essential variable on the response size of SOC and STN stocks. These results indicated that SOC and STN stocks following afforestation with R. pseudoacacia on cropland could be enhanced through plantation management practices.

It is of great value to develop general, low-cost and even household methods for colorectal cancer detection. Here, a portable detection strategy based on a personal glucose meter (PGM) was designed for meeting this purpose. In this strategy, the anti-EpCAM coated magnet beads (MBs) were used as capture probes for enriching cancer cells and the aptamer modified and invertase loaded graphene oxides (GO) were used as report probes for producing glucose signal. This method is sensitive with detection limit as low as 560 cells, and demonstrates excellent detection specificity. Meanwhile, we succeeded in the specific detection of target cells in 20% human serum samples, indicating this method has great prospect in clinical diagnosis. Moreover, this method presents favourable universality for detecting different colorectal cancer cells by just using different recognition aptamers. Importantly, this method can be implemented for the target cell detection at room temperature without any expensive and large-scale instruments but a portable PGM. Therefore, this portable detection method possesses great potential in point-of-care detection of colorectal cancer cells.

The aim of this meta-analysis was to synthesize the effects of biochar amendment on soil enzyme activities (SEAs) related to carbon (C), nitrogen (N), and phosphorus (P) cycling. Based on 401 paired comparisons from 43 published studies, the SEAs and main influential factors were analyzed in response to biochar characteristics, soil properties, and experiment conditions. Results showed that biochar additions to soils overall increased the N- and P-cycling SEAs by 14 and 11%, respectively. The enhancement of the N- and P-cycling SEAs was mainly attributable to the microbial stimulation by biochar properties (i.e., nutrient content and porosity) and soil nutrients (e.g., soil organic C and total N). The enhancement was the most significant under the conditions with biochars produced at low temperatures and using feedstock materials with high nutrient content, and biochar applications in acidic or neutral soils, coarse or fine soils, and farmland soils. Biochar additions to soils overall reduced the C-cycling SEAs by 6.3%. The C-cycling SEAs were greatly suppressed under the conditions with low and very high biochar loads, biochars produced at high temperatures and with feedstock materials of herb and lignocellulose, and biochar applications in alkaline, fine, and forest soils. The results were mainly related to the adsorption and inhibition effects of biochars and soil properties (e.g., liming effect, high biochar porosity and aromatic C content) on fungi and the enzymes. Biochar feedstock, C/N and load, and soil total N were the main influential factors on the SEAs. The results from this study demonstrate that biochar amendment is beneficial to improving soil N and P cycling and C sequestration.

The objective of this study was to investigate the temperature sensitivity of labile and relatively recalcitrant forest soil carbon (C) pools amended with biochar during short-term incubation. Biochars were prepared using sugar cane residue under pyrolysis temperatures of 300 and 700 °C (i.e., BC300 and BC700), respectively. Coarse particulate organic matter and acid hydrolysis residue were separated from a forest soil and treated as the labile and recalcitrant C pools of the soil, respectively. Temperature sensitivity of the soil C pools was characterized using the Q10 values (i.e., the proportional increase in respiration per 10 °C rise). The increased Q10 values of treatments in the earlier stage were attributable to instantaneously increased aromatic C content. The following decreased Q10 values were related to the consumption of labile C. However, the two types of biochars led to similar Q10 values in the same C pools at the later stage of incubation, which was closely related to the nearly humic-like component content in the dissolved organic matter. The different temporal distributions of Q10 values were attributable to changes of aromatic C content and continuous consumption of labile components.

Long noncoding RNA serves important roles in gastric cancer (GC). However, the prognostic significance and tumorigenesis effect of AFAP1-antisense RNA 1 (AS1) in GC remain to be clarified. The present study was conducted in order to determine the expression level of AFAP1-AS1 by reverse transcription-quantitative polymerase chain reaction. It was demonstrated that AFAP1-AS1 expression level was higher in GC tissues in comparison with adjacent tissues. By analyzing 66 GC tissue specimens, AFAP1-AS1 expression level was found to be markedly associated with tumor size, clinical stage and differentiation. By performing multivariate Cox regression test, AFAP1-AS1 expression level was confirmed to be an independent factor for poor prognosis in patients with GC. Furthermore, SGC-7901 and BGC-823 cells were used for further investigation following transfection of an AFAP1-AS1 short hairpin RNA lentiviral vector. Knockdown of AFAP1-AS1 significantly inhibited GC cell proliferation, migration and invasion abilities in vitro. Finally, nude mice experiments confirmed that downregulation of AFAP1-AS1 in GC cells suppressed tumor growth in vivo. In conclusion, the results of the present study suggested that AFAP1-AS1 may serve as a valuable prognostic indicator and therapeutic target for GC.

The objective of this study was to investigate responses of soil microbial community structure changes and activities to biochar addition under different biochar characteristics, soil properties, and experiment conditions. A meta-analysis was conducted based on 265 datasets from 49 published studies. Results showed that biochar addition significantly increased the ratios of soil fungi to bacteria (F/B) and the ratios of Gram-positive bacteria to Gram-negative bacteria (G+/G-), and microbial biomass and activities. The enhancement of F/B ratios was most significant with addition of biochars produced at low temperatures to soils with lower pH and nutrients in a long-term condition, which improved ecosystem stability of agricultural soils. The F/B ratios were mainly affected by biochar nutrients, soil nutrients, and soil pH values. Biochar nutrients and structural properties (i.e., surface area and porosity) also played the important role in enhancing G+/G-, total microbial biomass, and activities of bacteria, fungi, and actinomycetes. The G+/G- ratios increased the most with addition of biochars produced with medium temperatures and residue accompanied with fertilizers in dry land (dried farmland) soils. High biochar load greatly improved the total phospholipid fatty acids, and activities of bacteria, fungi, and actinomycetes in fine/coarse, paddy soils, and soils with low nutrients, in turn increased the soil nutrient cycling. In addition, the structural properties of biochars were the most influencing factor to increase total microbial biomass and actinomycete activity. Overall, the enhancement of microbial activities and community structure shifts under biochar addition should promote soil nutrients cycling and carbon sequestration, and improve crop yields.

To compare the results of total laparoscopic distal gastrectomy (TLDG) and laparoscopy-assisted distal gastrectomy (LADG) and explore the safety and feasibility of TLDG.Data were collected and analyzed from patients underwent TLDG and LADG from January 2009 to December 2011 at our institution.127 LADG cases and 104 TLDG cases were included and balanced for age, sex, BMI, ASA scores, and CEA level in this study. A decrease in postoperative pain (P 0.001), wound infection rate (P = 0.013), and hospitalization time after surgery (P 0.001) was found in the TLDG group. Compared with the LADG group, there was no increase in operative time (P = 0.084), intraoperative blood loss (P = 0.061), or anastomotic fistula rate (P = 0.473). Statistical differences did not exist in recurrence and (or) metastasis (P = 0.204), 5-years disease-free survival (DFS) rate and overall survival (OS) (P = 0.570 and 0.560, respectively).As long as it follows the surgical principles of malignant tumor, TLDG can achieve the same therapeutic effect as LADG does. TLDG is safe and feasible for gastric cancer patients though further studies are needed.

Oral tongue squamous cell carcinoma (OTSCC) is one of the most common head and neck cancers. Innate or acquired resistance to cisplatin, a standard chemotherapy agent for OTSCC, is common in patients with OTSCC. Understanding the molecular basis for cisplatin chemoresistance in OTSCC cells may serve as a basis for identification of novel therapeutic targets. Podocalyxin (PODXL) has been found critical for malignant progression in a variety of cancers. Bmi1 has recently been found to induce cell apoptosis and cisplatin chemosensitivity in OTSCC cells. In this study, we explored the interaction between PODXL and Bmi1 in OTSCC cells, and assessed its impact on OTSCC cell chemoresistance to cisplatin. PODXL and/or Bmi1 were stably overexpressed or knocked down in SCC-4 and Tca8113 human OTSCC cells. Overexpression of PODXL in both cell lines markedly elevated the expression level of Bmi1 and the half maximal inhibitory concentration (IC50) of cisplain and reduced cisplatin-induced cell apoptosis, which was abolished by knockdown of Bmi1 or a selective focal adhesion kinase (FAK) inhibitor. On the other hand, knockdown of PODXL significantly decreased the Bmi1 expression level and cisplatin IC50 and increased cisplatin-induced cell apoptosis, which was completely reversed by overexpression of Bmi1. While overexpression and knockdown of PODXL respectively increased and decreased the FAK activity, Bmi1 showed no significant effect on the FAK activity in OTSCC cells. In addition, overexpression of PODXL markedly elevated the stability of Bmi1 mRNA, which was abolished by a selective FAK inhibitor. In conclusion, this study provides the first evidence that PODXL up-regulates the expression level of Bmi1 in OTSCC cells by increasing the stability of Bmi1 mRNA through a FAK-dependent mechanism; this effect leads to enhanced cisplatin chemoresistance in OTSCC cells. This study adds new insights into the molecular mechanisms underlying OTSCC chemoresistance.