Mass Loss and Chemical Structures of Wheat and Maize Straws in Response to Ultravoilet-B Radiation and Soil Contact

The role of photodegradation, an abiotic process, has been largely overlooked during straw decomposition in mesic ecosystems. We investigated the mass loss and chemical structures of straw decomposition in response to elevated UV-B radiation with or without soil contact over a 12-month litterbag experiment. Wheat and maize straw samples with and without soil contact were exposed to three radiation levels: a no-sunlight control, ambient solar UV-B, and artificially elevated UV-B radiation. A block control with soil contact was not included. Compared with the no-sunlight control, UV-B radiation increased the mass loss by 14-19% and the ambient radiation by 9-16% for wheat and maize straws without soil contact after 12 months. Elevated UV-B exposure decreased the decomposition rates of both wheat and maize straws when in contact with soil. Light exposure resulted in decreased O-alkyl carbons and increased alkyl carbons for both the wheat and maize straws compared with no-sunlight control. The difference in soil contact may influence the contribution of photodegradation to the overall straw decomposition process. These results indicate that we must take into account the effects of photodegradation when explaining the mechanisms of straw decomposition in mesic ecosystems

An Updated Meta-Analysis of the Associations Between MicroRNA Polymorphisms and Susceptibility to Rheumatoid Arthritis

Aims: Rheumatoid arthritis (RA) is characterized by cartilage and bone damage leading to disability. Here, the association between microRNA (miRNA) polymorphisms and susceptibility to RA was evaluated by performing an updated meta-analysis and systematic review.Main methods: An electronic search of databases including PubMed and Embase was performed from inception to December 8, 2017 to retrieve studies investigating the association between miRNA polymorphisms and RA risk. Two reviewers independently screened literature according to the inclusion and exclusion criteria and extracted data. The meta-analysis was conducted using Stata 14.0 software.Key findings: Thirteen case-control studies with 2660 cases and 4098 controls were screened out after a systematic search. One study from the miR-146a rs2910164 G > C polymorphism group and two from the miR-499 rs3746444 T > C polymorphism group were excluded because of deviations from Hardy-Weinberg equilibrium. Pooled analysis demonstrated that miR-146a rs2910164 G > C polymorphism was not significantly associated with susceptibility to RA. However, a significant association was observed between miR-499 rs3746444 T > C polymorphism and RA risk (C vs. T: OR = 1.22, 95% CI = 1.05–1.42, P = 0.008; TC vs. TT: OR = 1.26, 95% CI = 1.05–1.50, P = 0.011; TC/CC vs. TT: OR = 1.26, 95% CI = 1.07–1.5, P = 0.007). Subgroup analysis based on ethnicity showed no significant association between miR-499 T > C polymorphism and susceptibility to RA in the Asian population (P > 0.05). However, in Caucasian population, the C allele in the miR-499 T > C polymorphism was a contributor to RA susceptibility in some genetic models (C vs. T: OR = 1.64, 95% CI = 1.28–2.11, P < 0.001; TC vs. TT: OR = 1.95, 95% CI = 1.40–2.71, P < 0.001; TC/CC vs. TT: OR = 1.96, 95% CI = 1.43–2.69, P < 0.001).Significance: The miR-146a rs2910164 G > C polymorphism was not associated with susceptibility to RA. In the Caucasian population, the C allele in the miR-499 T > C polymorphism contributed to RA susceptibility

Myocardin immunohistochemistry index is associated with clinical prognosis in nasopharyngeal carcinoma: a clinical practice-based cohort study

Purpose: Recent findings have implicated the role of myocardin re-expression in carcinogenesisHowever, the clinical functions of myocardin in nasopharyngeal carcinoma (NPC) is not known yet. The purpose for the cohort research was to investigate whether myocardin re-expression level may predict clinical prognosis in NPC patients.Methods: 148 NPC patients were recruited from September, 2005 to September, 2011 with median follow-up time of 4.5 years in a clinical practice setting. At study entry myocardin re-expression of these patients was determined using immunohistochemistry (IHC) and additional 20 normal nasopharyngeal tissues were included as control. Two-sample t-test was used to compare mean myocardin reexpression levels and Chi-square test was used for comparing tumour recurrence rate. Logistic regression analysis was used for tumour local control rate, and log-rank test, Kaplan-Meier estimates and Cox proportional hazard model for disease-free survival and overall survival.Results: Myocardin IHC index was significantly downregulated in NPC samples than in normalnasopharyngeal tissues (mean ± standard deviation, 61.2 ±31.5 vs. 109.9 ±73.6, P= 0.009). However, among NPC patients was observed a roughly V-shaped change of myocardin IHC index according to Tumour T-stage (P=0.067); meanwhile higher IHC level was associated with more tumour recurrence rate in NPC patients (High vs. Low: 21.6% vs. 8.1%; P=0.021). Logistic regression analysis equally showed high myocardin IHC level was an independent risk factor for local tumour control rate regardless of adjustments [High vs. Low: unadjusted Odds Ratio (OR) 0.320, 95% confidence interval (CI): 0.117 to 0.871; P=0.026]. Moreover, higher myocardin IHC level was associated with a marginal but not significant risk increase of disease-free survival [High vs. Low: adjusted Hazard Ratio (HR) 1.760, 95% CI: 0.981 to 3.158; log-rank: P=0.129]. A less obvious trend was observed with regard to overall survival [adjusted HR 1.409, 95% CI: 0.715 to 2.77; log-rank: P=0.745].Conclusion: The study results suggested that high myocardin IHC index level could be a potential clinically prognostic intermediate biomarker for tumour recurrence for NPC patients in routine practice. Large well-designed cohort studies involving IHC re-expression change over time is needed

LAPTM4B Targeting as Potential Therapy for Hepatocellular Carcinoma

HCC is one of the most common cancers worldwide with high prevalence, recurrence, and lethality. The curative rate is not satisfactory. LAPTM4B is a novel driver gene of HCC first indentified by our group. It is over-expressed in 87.3% of HCC. The expression levels of the encoded LAPTM4B-35 protein in HCC is also over-expressed in 86.2% of HCC and shows a significant positive correlation with pathological grade, metastasis, and recurrence, and a negative correlation with postoperative overall- and cancer free- survival of HCC patients. Moreover, HCC cells showing high expression of LAPTM4B-35 show a strong tendency to metastasize and enhanced drug resistance. Overexpression of this gene promotes tumorigenesis, faster growth of human HCC xenografts and metastasis in nude mice, and leads to anti-apoptosis, deregulation of proliferation, enhancement of migration and invasion, as well as multi-drug resistance. In addition, overexpression of LAPTM4B-35 leads to accumulation of a number of oncoproteins and to down-regulation of a number of tumor suppressing proteins. By contrary, knockdown of endogenous LAPTM4B-35 via RNAi results in remarkable inhibition of xenograft growth and metastasis of human HCC in nude mice. Also, RNAi knockdown of LAPTN4B-35 can reverse the cellular and molecular malignant phenotypes noted above