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Background Migraine is defined as a recurrent headache of moderate to severe intensity that seriously affects the quality of life. Recent clinical trials have confirmed that acupuncture is effective in treating migraine. We aimed to review the effectiveness of acupuncture in the treatment of migraine by comparing treatment and various control groups in accordance with the newly published guidelines for systematic reviews. Materials and Methods The following databases were searched for relevant articles published from January 1, 2010 to December 31, 2019: Embase, PubMed, Medline, Cochrane Library, and four Chinese databases. The present review included randomized controlled trials in which acupuncture was the sole treatment or an adjunctive treatment for migraine. Two researchers independently conducted the study selection, data extraction, and quality assessment processes. Disagreements between reviewers were solved by discussion and data reanalysis. The quality of each included study was evaluated using the Cochrane Collaboration risk-of-bias assessment method and the Standards for Reporting Interventions in Controlled Trials of Acupuncture (STRICTA) checklist. Results Forty-nine studies were analyzed and ranked based on the latest STRICTA and Cochrane Collaboration risk-of-bias assessment standards. The analysis revealed that acupuncture reduced headache frequency compared with no treatment (mean difference [MD] = -1.80, P < 0.00001, 95% confidence interval [CI] -2.34 to -1.26) and western medicine (MD = -1.75, P = 0.003, 95% CI -2.91 to -0.58). Headache frequency did not significantly differ between patients who received real acupuncture versus those who received sham acupuncture (MD = -0.64, P = 0.24, 95% CI -1.70 to 0.42). Conclusion The present review evaluated the current research on the use of acupuncture for migraine, compared with various control treatments. The evidence for the effectiveness of acupuncture in controlling migraine is still limited due to the low quality of the published studies.

Transient ischaemic attack (TIA) and cerebral infarction are difficult to identify within the thrombolytic time window. Blood markers are efficient, economical and noninvasive and can be beneficial in the diagnosis of many diseases. Plasma exosomal biomarkers are rarely reported in TIA. Exosomal microRNAs (miRNAs) were extracted from plasma and cerebrospinal fluid after middle cerebral artery occlusion (MCAo) in rats (0 min, 5 min, 10 min, 2 h). Deep sequencing was used to detect exosomal miRNAs in rat plasma and confirm significant differentially expressed miRNAs. Polymerase chain reaction (PCR) was used to detect the differentially expressed miRNAs in plasma and cerebrospinal fluid. Exosomal miRNAs with the same expression trends in plasma and cerebrospinal fluid were selected, and bioinformatics analysis was then carried out. Finally, the area under the curve (AUC) of the receiver operating characteristic (ROC) curve was determined to assess the diagnostic accuracy of miRNAs for TIA in rats. First, high-throughput sequencing was used to detect the expression level of plasma exosome miRNA, and rno-miR-450b-5p with a decreasing expression level was screened. Second, the expression levels of exosomal miRNAs were verified in cerebrospinal fluid and plasma samples by PCR, and the results indicated that exosomal rno-miR-450b-5p was similarly expressed in cerebrospinal fluid and plasma. ROC analysis showed high AUC values for rno-miR-450b-5p (0.880) in the 10 min ischaemia rats compared with the control rats. Finally, bioinformatic analysis indicated that exosomal rno-miR-450b-5p may be involved in cerebral ischaemia. Plasma exosomal rno-miR-450b-5p has a high diagnostic value and may become a therapeutic target for rat TIA.

Thioredoxin system plays an important role in antioxidative stress, thioredoxin 2 (Trx2) being one of the most important components in the thioredoxin system. The full-length cDNA sequence of thioredoxin 2 from Euphausia superba (EsTrx2) is 1276 bp and contain a 5′ untranslated region (UTR) of 94 bp, a 3′ UTR of 741 bp and an open reading frame (ORF) of 441 bp, encoding a putative protein of 146 amino acids. Multiple sequence alignments have indicated that EsTrx2 possesses a conserved (-Cys-Gly-Pro-Cys-) CGPC redox-active site. EsTrx2 shares 62.3% identity with the swimming crab (Portunus trituberculatus) Trx2. The predicted three-dimensional structure of EsTrx2 consists of a thioredoxin fold. The high similarity and phylogenetic analysis have indicated that EsTrx2 is a member of the mitochondrial Trx2 sub-family. The recombinant EsTrx2 (rEsTrx2) was constructed and expressed in Escherichia coli BL21 (DE3). The rEsTrx2 protein showed high redox activity and antioxidant capacity at temperature from 4 to 37 °C. All results indicated that EsTrx2 was involved in the oxidative stress response of E. superba.

Cucurbita maxima belong to the genus Cucurbita and are of nutritional and economic importance. Physiological activity, transcriptome, and metabolome analyses of leaf samples from the C. maxima inbreding line IL7 treated at 5 °C and 25 °C were performed. Cold stress resulted in a significant increase in the malondialdehyde content, relative electrical conductivity, soluble protein, sugar content, and catalase activity. A total of 5,553 differentially expressed genes were identified, of which 2,871 were up-regulated and 2,682 down-regulated. In addition, the transcription of differentially expressed genes in the plant hormone signal transduction pathway and transcription factor families of AP2/ERF, bHLH, WRKY, MYB, and HSF was activated. Moreover, 114 differentially expressed metabolites were identified by gas chromatography time-of-flight mass spectrometry, particularly through the analysis of carboxylic acids and derivatives, and organooxygen compounds. The demonstration of a series of potential metabolites and corresponding genes highlighted a comprehensive regulatory mechanism. These findings will provide novel insights into the molecular mechanisms associated with the response to cold stress in C. maxima.

Background: Radiation-induced xerostomia is one of the most common symptoms experienced by cancer patients. The aim of our study is to evaluate the preventive and therapeutic effect of acupuncture for radiation-induced xerostomia in cancer patients. Methods: Eight databases were searched for all published randomized clinical trials (RCTs) on acupuncture for radiation-induced xerostomia in cancer patients up to December 31, 2019. Manual searching included other conference abstracts and reference lists. Meta-analysis was conducted using Revman V.5.3, and risks of bias for included studies was assessed following the Cochrane Handbook. Results: Eight clinical trials (725 participants) were analyzed, and 3 were included in a meta-analysis. All included trials had a high risk of bias, such as selection, performance, and detection bias. Analysis indicated favorable effects of acupuncture regarding the improvement of xerostomia symptoms (MD −3.05, P = 0.02, 95% CI −5.58 to −0.52), compared with sham acupuncture. There were no significant differences between real acupuncture and sham acupuncture regarding the stimulated salivary flow rate (MD 0.37, P = 0.08, 95% CI −0.05 to 0.79) and unstimulated salivary flow rate (MD 0.09, P = 0.12, 95% CI −0.02 to 0.21), which were whole salivary flow rate. Compared with no acupuncture (standard oral care, usual care, or no treatment), acupuncture produced a significant improvement in patient-reported xerostomia, without causing serious adverse effects. However, a Grading of Recommended Assessments analysis revealed that the quality of all acupuncture outcome measures was low. Conclusion: The present meta-analysis and systematic review suggests that acupuncture is effective at improving xerostomia symptoms in cancer patients but not at objective salivary flow measurements. The evidence is still limited due to the low quality of the published studies.

Panicle number (PN) is one of the three yield components in rice. As one of the most unstable traits, the dynamic change in tiller number (DCTN) may determine the final PN. However, the genetic basis of DCTN and its relationship with PN remain unclear. Here, 377 deeply re-sequenced rice accessions were used to perform genome-wide association studies (GWAS) for tiller/PN. It was found that the DCTN pattern rather than maximum tiller number or effective tiller ratio is the determinant factor of high PN. The DCTN pattern that affords more panicles exhibits a period of stable tillering peak between 30 and 45 days after transplant (called DT30 and DT45, respectively), which was believed as an ideal pattern contributing to the steady transition from tiller development to panicle development (ST-TtP). Consistently, quantitative trait loci (QTL) expressed near DT30-DT45 were especially critical to the rice DCTN and in supporting the ST-TtP. The spatio-temporal expression analysis showed that the expression pattern of keeping relatively high expression in root at 24:00 (R24-P2) from about DT30 to DT45 is a typical expression pattern of cloned tiller genes, and the candidate genes with R24-P2 can facilitate the prediction of PN. Moreover, gene OsSAUR27 was identified by an integrated approach combining GWAS, bi-parental QTL mapping and transcription. These findings related to the genetic basis underlying the DCTN will provide the genetic theory in making appropriate decisions on field management, and in developing new varieties with high PN and ideal dynamic plant architecture.

As one of the main yield components, grain number per panicle (GNP) played critical role in the rice yield improvement. The identification of natural advantageous variations under different situations will promote the sustainable genetic improvement in rice yield. This study was designed to identify natural genotypes in a rice mini-core collection, to examine the genotypic effects across the indica and japonica genetic background in different environments, and excavating the superior genotypes that had drove the modern genetic improvement. The association mapping of GNP was carried out using a mini-core collection including 154 indica and 119 japonica accessions in seven different environments. Genotypic effects of each genotype for each QTL were calculated and genotype frequency distortion between the commercial rice cultivars and landraces was screened by χ2-test. In total, 74 QTLs containing stable and sensitive QTLs in various environments were detected. Within them, 20 positive and 24 negative genotypes in indica, and 24 positive and 16 negative genotypes in japonica were identified. When checking the accumulation of positive genotypes identified in indica across cultivars in each of the two subspecies, it indicated that increased number of positive genotypes identified in indica results in the substantially increased GNP in both indica and japonica across all of the environments, while this trend was not obvious for the positive genotypes identified in japonica especially in short day environments. Moreover, the positive and negative genotype frequency distortion between the landraces and commercial rice cultivars indicated that both positive selection of positive genotypes and negative selection of negative genotypes had driven the genetic improvement on GNP. Our findings suggested that the accumulation of positive genotypes and purifying negative genotypes played equivalently important roles in the improvement of rice yield, but the efficient use for some QTLs or genotypes depends on the comprehensive evaluation of their effect under diverse genetic backgrounds and environments.

Pyropia yezoensis is commonly known as a valuable marine red alga. As a cold-temperate species, high temperature is a critical abiotic stress factor that can affect the growth and development of this seaweed. Exploring the regulatory mechanisms of P. yezoensis resistance to high temperatures has significance in breeding high temperature-resistant strains. To investigate the potential role of microRNA (miRNA) regulation in heat stress, we constructed and sequenced four libraries (one control and three heat stressed). A total of 1213 miRNAs, corresponding to 174 miRNA families and 10 miRNAs precursors producing 14 novel mature miRNAs were identified. Among them, 98 miRNAs were differentially expressed under heat stress. The quantitative PCR of six selected miRNAs verified the deep sequencing data. This study represents the first set of heat-responsive miRNAs from P. yezoensis, and provides valuable information for understanding the miRNA-mediated heat stress responses and resistance mechanisms in P. yezoensis. The results offer a foundation for future studies on the genetic improvement of Pyropia heat stress tolerance.

// Jie Zhu 1 , Huirong Shi 1 , Huina Liu 1 , Xiaojuan Wang 1 and Fengmei Li 2 1 Department of Gynecology and Obstetrics, The First Affiliated Hospital of Zhengzhou University, Zhengzhou 450052, Henan, China 2 Department of Obstetrics and Gynecology, Zhengzhou Central Hospital, Zhengzhou 450000, Henan, China Correspondence to: Jie Zhu, email: jiezhu0073@163.com Keywords: cervical cancer, TUG1, SIRT1, miR-138-5p, Wnt/β-catenin Received: March 21, 2017 Accepted: April 07, 2017 Published: May 26, 2017 ABSTRACT Increasing evidences showed that long non-coding RNAs (lncRNAs) play vital roles in tumor progression. Recent studies indicated that lncRNA TUG1 was upregulated and promoted tumor processes in several cancers. However, the expression and underlying mechanism of TUG1 in cervical cancer remain unclear. In the present study, we found that TUG1 expression was upregulated in cervical cancer tissues and correlated with advanced clinical features and poor overall survival. TUG1 knockdown suppressed cervical cancer cell growth and metastasis in vitro and tumor growth in vivo . In addition, our results indicated that TUG1 could act as an endogenous sponge by directly binding to miR-138-5p and suppressed miR-138-5p expression. Furthermore, we found that TUG1 could reverse the inhibitory effect of miR-138-5p on cervical cancer cells processes, which might be involved in the activation of SIRT1, a target gene of miR-138-5p, and activation of Wnt/β-catenin signaling pathway. Taken together, we elucidated that TUG1 might promote cervical cancer malignant progression via miR-138-5p-SIRT1-Wnt/β-catenin signaling pathway axis.

The basic helix-loop-helix (bHLH) transcription factors (TFs) form a huge superfamily and play crucial roles in many essential developmental, genetic, and physiological-biochemical processes of eukaryotes. In total, 109 putative bHLH TFs were identified and categorized successfully in the genomic databases of cattle, Bos Taurus, after removing redundant sequences and merging genetic isoforms. Through phylogenetic analyses, 105 proteins among these bHLH TFs were classified into 44 families with 46, 25, 14, 3, 13, and 4 members in the high-order groups A, B, C, D, E, and F, respectively. The remaining 4 bHLH proteins were sorted out as 'orphans.' Next, these 109 putative bHLH proteins identified were further characterized as significantly enriched in 524 significant Gene Ontology (GO) annotations (corrected P value ≤ 0.05) and 21 significantly enriched pathways (corrected P value ≤ 0.05) that had been mapped by the web server KOBAS 2.0. Furthermore, 95 bHLH proteins were further screened and analyzed together with two uncharacterized proteins in the STRING online database to reconstruct the protein-protein interaction network of cattle bHLH TFs. Ultimately, 89 bHLH proteins were fully mapped in a network with 67 biological process, 13 molecular functions, 5 KEGG pathways, 12 PFAM protein domains, and 25 INTERPRO classified protein domains and features. These results provide much useful information and a good reference for further functional investigations and updated researches on cattle bHLH TFs.

Integration of dark- and photo-fermentation is a promising strategy to enhance saline wastewater treatment efficiency and biohydrogen production. In this study, dark- and photo-fermentative bacterial consortium was respectively enriched and their communities were analyzed using polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE). Both consortia were mainly composed of hydrogen-producing strains. After the first-stage dark-fermentation, the following conditions were applied prior to the second-stage fermentation: fermentative broth pH regulation (the pH group), glucose addition (the glucose group), glucose addition and pH regulation (the glucose + pH group), photosynthetic bacteria addition (the photo group), and photosynthetic bacteria addition and pH regulation (the photo + pH group), respectively. Dark fermentative broth with no pretreatment was used as control (the control group). Then the second stage began. The results showed that pH restriction had more influence than substrate or products restriction on dark-fermentative hydrogen production. Addition of photo-fermentative bacteria after dark-fermentation increased the hydrogen yield (134%) and substrate utilization (67%). These findings indicated syntrophic interactions between dark- and photo-fermentative bacteria during the hydrogen production process.

Myocardial failure has a negative impact on the quality of human life. MicroRNA (miR) expression abnormalities lead to the development of many pathological conditions, including myocardial failure, and therefore the present study primarily focused on the investigation of the functions of miR‑127 in the development of myocardial failure. The miR‑127 expression levels in serum samples from patients with myocardial failure were examined. Oil red O staining was used to analyze the characteristics of the myocardium of the patients. Immunohistochemistry was used to detect fatty acid synthase (FASN), stearoyl‑CoA desaturase‑1 (SCD1) and mitochondrial brown fat uncoupling protein 1 (UCP1) protein expression in the myocardium of the patients. Furthermore, C57BL/6J (B6) mice were induced with 15 mg/kg of doxorubicin. Echocardiography was used to detect the histopathological alterations of the myocardial cells by comparison of the myocardial tissues from the myocardial failure animal model and normal C57BL/6 mice. Reverse transcription‑quantitative polymerase chain reaction was used to detect the expression levels of miR‑127 following different induction periods and immunohistochemistry was used to detect the expression of transforming growth factor‑β1 (TGF‑β1) and mothers against decapentaplegic homolog 3 (Smad3). Immunofluorescence was used to detect the expression alterations TGF‑β1/Smad3 when miR‑127 overexpression or inhibition was established. The results of the present study indicated that myocardial failure resulted in an upregulated expression of miR‑127 and severe fat accumulation. FASN, SCD1 and UCP1 were highly expressed in the myocardial failure group compared with the control. Abdominal artery contraction and the ejection fraction were significantly reduced in the DOX‑induced B6 mice. The cardiomyocytes became hypertrophic, and left ventricular systolic pressure and left ventricular maximum ejection pressure were altered following DOX induction in B6 mice. The results confirmed that miR‑127 regulates the expression of TGF‑β1/Smad3. The potential pathological mechanism of the effect of miR‑127 may be based on the upregulation of the TGF‑β1/Smad3 signaling pathway.

Avoidance of disadvantageous genetic correlations among growth duration and yield traits is critical in developing crop varieties that efficiently use light and energy resources and produce high yields. To understand the genetic basis underlying the correlations among heading date and three major yield traits in rice, we investigated the four traits in a diverse and representative core collection of 266 cultivated rice accessions in both long-day and short-day environments, and conducted the genome-wide association study using 4.6 million single nucleotide polymorphisms (SNPs). There were clear positive correlation between heading date and grain number per panicle, and negative correlation between grain number per panicle and panicle number, as well as different degrees of correlations among other traits in different subspecies and environments. We detected 47 pleiotropic genes in 15 pleiotropic quantitative trait loci (pQTLs), 18 pleiotropic genes containing 37 pleiotropic SNPs in 8 pQTLs, 27 pQTLs with r2 of linkage disequilibrium higher than 0.2, and 39 pairs of interactive genes from 8 metabolic pathways that may contribute to the above phenotypic correlations, but these genetic bases were different for correlations among different traits. Distributions of haplotypes revealed that selection for pleiotropic genes or interactive genes controlling different traits focused on genotypes with weak effect or on those balancing two traits that maximized production but sometimes their utilization strategies depend on the traits and environment. Detection of pQTLs and interactive genes and associated molecular markers will provide an ability to overcome disadvantageous correlations and to utilize the advantageous correlations among traits through marker-assisted selection in breeding.

Cadmium (Cd) accumulation in rice grain poses a serious threat to human health. While several transport systems have been reported, the complicity of rice Cd transport and accumulation indicates the necessity of identifying additional genes, especially those that are responsible for Cd accumulation divergence between indica and japonica rice subspecies. Here, we show that a gene, OsCd1, belonging to the major facilitator superfamily is involved in root Cd uptake and contributes to grain accumulation in rice. Natural variation in OsCd1 with a missense mutation Val449Asp is responsible for the divergence of rice grain Cd accumulation between indica and japonica. Near-isogenic line tests confirm that the indica variety carrying the japonica allele OsCd1V449 can reduce the grain Cd accumulation. Thus, the japonica allele OsCd1V449 may be useful for reducing grain Cd accumulation of indica rice cultivars through breeding., Grain of indica rice accumulates more toxic cadmium (Cd) than japonica, but the underlying genetic basis is unclear. Here, the authors show that natural variation of OsCd1 contributes to divergence in grain Cd accumulation and transferring japonica allele to indica rice leads to reduced Cd accumulation.

Myocardial failure has a negative impact on the quality of human life. MicroRNA (miR) expression abnormalities lead to the development of many pathological conditions, including myocardial failure, and therefore the present study primarily focused on the investigation of the functions of miR-127 in the development of myocardial failure. The miR-127 expression levels in serum samples from patients with myocardial failure were examined. Oil red O staining was used to analyze the characteristics of the myocardium of the patients. Immunohistochemistry was used to detect fatty acid synthase (FASN), stearoyl-CoA desaturase-1 (SCD1) and mitochondrial brown fat uncoupling protein 1 (UCP1) protein expression in the myocardium of the patients. Furthermore, C57BL/6J (B6) mice were induced with 15 mg/kg of doxorubicin. Echocardiography was used to detect the histopathological alterations of the myocardial cells by comparison of the myocardial tissues from the myocardial failure animal model and normal C57BL/6 mice. Reverse transcription-quantitative polymerase chain reaction was used to detect the expression levels of miR-127 following different induction periods and immunohistochemistry was used to detect the expression of transforming growth factor-β1 (TGF-β1) and mothers against decapentaplegic homolog 3 (Smad3). Immunofluorescence was used to detect the expression alterations TGF-β1/Smad3 when miR-127 overexpression or inhibition was established. The results of the present study indicated that myocardial failure resulted in an upregulated expression of miR-127 and severe fat accumulation. FASN, SCD1 and UCP1 were highly expressed in the myocardial failure group compared with the control. Abdominal artery contraction and the ejection fraction were significantly reduced in the DOX-induced B6 mice. The cardiomyocytes became hypertrophic, and left ventricular systolic pressure and left ventricular maximum ejection pressure were altered following DOX induction in B6 mice. The results confirmed that miR-127 regulates the expression of TGF-β1/Smad3. The potential pathological mechanism of the effect of miR-127 may be based on the upregulation of the TGF-β1/Smad3 signaling pathway.

The human ether-a-go-go related gene (hERG) encodes the rapid delayed rectifier K+ channel. hERG not only serves an important role in heart muscle and cardiomyocyte excitability by regulating action potential repolarization, but also represents a selective advantage for cancer cell proliferation. Arsenic trioxide is a traditional Chinese medicine, which has been previously identified as an efficient tumor suppressor, particularly in the treatment of acute pro-myelocytic leukemia. However, studies have also reported that long-term exposure to arsenicals may lead to the formation of malignant tumors. In the present study, the effect of low-dose arsenic trioxide on the proliferation and apoptosis of tumor cells was investigated, as were the potential underlying mechanisms of this effect. The data demonstrated that low-dose arsenic trioxide (0.1 µM) enhanced the viability and apoptosis of tumor cells expressing hERG channels following long-term incubation. However, in tumor cells lacking hERG channels, low-dose arsenic trioxide had no effect. Therefore, we hypothesized that this hormesis effect of low-dose arsenic trioxide on tumor cells may be associated with the hERG channel. Furthermore, low dose arsenic trioxide promoted the hERG-channel current by changing the kinetics of channel gating and prolonging the open-channel stage. Simultaneously, high-dose As2O3 (1 or 10 µM) significantly reduced the expression of hERG in tumor cells compared with the control group, which resulted in reduced proliferation rate and promotion of apoptotic rate. The results of the present study demonstrate that the dual effects of arsenic trioxide on hERG channels vary according to concentration, resulting in the dual effects on tumor cells. This provides a theoretical basis for the potential clinical application of arsenic trioxide, suggesting that hERG channels are an important target in preventing and treating tumorigenesis during arsenicosis.

Arsenic trioxide (As2O3) has been verified as a breakthrough in the management of acute promyelocytic leukemia in recent decades. However, cardiotoxicity, especially long QT syndrome (LQTS) has become the most important issue during As2O3 treatment. The characterized mechanisms behind this adverse effect are inhibition of cardiac hERG channel trafficking and increase of cardiac calcium currents. In our study, we found a new pathway underlying As2O3-induced cardiotoxicity that As2O3 accelerates lysosomal degradation of hERG on plasma membrane after using brefeldin A (BFA) to block protein trafficking. Then we explored pharmacological rescue strategies on As2O3-induced LQTS, and found that 4 therapeutic agents exert rescue efficacy via 3 different pathways: fexofenadine and astemizole facilitate hERG trafficking via promotion of channel-chaperone formation after As2O3 incubation; ranolazine slows hERG degradation in the presence of As2O3; and resveratrol shows significant attenuation on calcium current increase triggered by As2O3. Moreover, we used human-induced pluripotent stem cell derived cardiomyocytes (hiPS-CMs) to evaluate the rescue effects of the above agents on As2O3-induced prolongation of action potential duration (APD) and demonstrated that fexofenadine and resveratrol significantly ameliorate the prolonged APD. These observations suggested that pharmacological chaperone like fexofenadine and resveratrol might have the potential to protect against the cardiotoxicity of As2O3.

IntroductionXerostomia is a common symptom in patients with cancer. Currently available methods to manage xerostomia include stringent oral hygiene using fluoride agents and antimicrobials, saliva substitutes and sialagogic agents, but side effects such as headache, dizziness and sweating can occur with these therapies. Clinical trials have shown that acupuncture may be effective in treating xerostomia. The objective of this systematic review is to assess the effectiveness and safety of acupuncture treatment for xerostomia caused by cancer.Methods and analysisThis systematic review will incorporate articles identified by electronically searching the following databases: PubMed, MEDLINE, the Cochrane Library, AMED, EMbase, WorldSciNet, Nature, Science Online, China National Knowledge Infrastructure, the Chongqing VIP Chinese Science and Technology Periodical Database, the Wanfang Database and China Biology Medicine Disc from inception to 1 December 2019. Other sources including conference proceedings and reference lists of identified publications and existing systematic reviews will also be searched. Two reviewers will independently search the databases, perform data extraction and assess the quality of studies. Data will be synthesised using either a fixed-effects model or a random-effects model, according to heterogeneity testing. Patient-reported change in the Visual Analogue Scale or the Xerostomia Inventory will be assessed as the primary outcome. Saliva collection, whole saliva production and the European Organisation for Research and Treatment of Cancer Quality of Life Questionnaire C30 will be evaluated as secondary outcomes. RevMan V. 5.3 will be employed for data analysis. The results will be expressed as risk ratios for dichotomous data and mean differences for continuous data.Ethics and disseminationThis protocol will not evaluate individual patient information or affect patient rights and therefore does not require ethical approval. Results from this review will be disseminated through peer-reviewed journals and conference reports.Trial registration numberCRD42019129069.

Thioredoxins, with a dithiol/disulfide active site (CGPC) are major highly conserved and ubiquitous proteins that are involved in protecting organisms against various oxidative stresses. In the present study, a novel thioredoxin gene was identified in antarctic microcrustacean, Euphausia superba (designated as EsTrx1). The full-length cDNA sequences of EsTrx1 was of 621 bp, containing a 5' untranslated region (UTR) of 45 bp, a 3' UTR of 276 bp and an open reading frame (ORF) of 303 bp encoding a putative protein of 100 amino acids. The predicted molecular weight of EsTrx1 was 11.08 kDa and the theoretical isoelectric point was 4.51. Multiple sequence alignment indicated that the EsTrx1 possessed conserved CGPC redox-active site. EsTrx1 shared 68.6% similarity with the Chinese mitten crab (Eriocheir sinensis) Trx1. The predicted three-dimensional structure of EsTrx1 consisted of a central core of a four-stranded β-sheet and four flanking α-helices. The high similarity of EsTrx1 with Trx1s from other animals together with the phylogenetic analysis indicated that EsTrx1 could be a novel member of Trx1 sub-family. In order to elucidate its biological functions, the recombinant EsTrx1 was constructed and expressed in Escherichia coli BL21 (DE3). Experiments demonstrated that the rEsTrx1 fusion protein possessed the expected redox activity in enzymatic analysis, and be more potent than GSH in antioxidant capacity. These results together indicated that EsTrx1 could be involved in the oxidative stress response of E. superba.