The effect of Clostridium tyrobutyricum Spo0A overexpression in the intestine of mice

Clostridium tyrobutyricum shows probiotic properties and can affect the composition of gut microbiota and regulate the intestinal immune system. Compared with other probiotics, this spore-producing bacterium shows unparalleled advantages in commercial production. In addition to being resistant to extreme living environments for extended periods, its endophytic spores are implicated in inhibiting cancer cell growth. We speculated that C. tyrobutyricum spores can also promote gut health, which mean it can maintain intestinal homeostasis. To date, the beneficial effects of C. tyrobutyricum spores on gut health have not been reported. In this study, a Spo0A-overexpressing C. tyrobutyricum strain was developed to increase spore production, and its probiotic effects on the gut were assessed. Compared with the wild-type, the engineered strain showed significantly increased sporulation rates. Mice administered with the engineered strain exhibited enhanced intestinal villi and the villus height/crypt depth ratio, weight gain and improved Firmicutes/Bacteroidetes ratio to facilitate intestinal homeostasis. This study demonstrated for the first time that enhanced spore production in C. tyrobutyricum can improve intestinal homeostasis, which is advantageous for its commercial application in food and pharmaceutical industry.

MicroRNA-1271 inhibits the progression of papillary thyroid carcinoma by targeting IRS1 and inactivating AKT pathway

OBJECTIVE

The important role of microRNA-1271 (miR-1271) has been identified in human diseases and cancers. However, the biological function of miR-1271 remains ambiguous in papillary thyroid carcinoma (PTC). Therefore, the specific role of miR-1271 was investigated in PTC.

PATIENTS AND METHODS

The expressions of miR-1271 and insulin receptor substrate 1 (IRS1) were detected by quantitative Real Time-Polymerase Chain Reaction (qRT-PCR) assay. The protein expression of the genes was measured by Western blot analysis. The function of miR-1271 was investigated using methyl thiazolyl tetrazolium (MTT) and transwell assays. The Dual-Luciferase assay was used to observe the relationship between miR-1271 and IRS1.

RESULTS

MiR-1271 was downregulated in PTC tissues. Moreover, overexpression of miR-1271 suppressed migration, invasion and proliferation of PTC cells. Furthermore, IRS1 was indicated as a direct target gene of miR-1271 and knockdown of IRS1 inhibited cell migration, invasion and proliferation in PTC. In addition, miR-1271 inhibited the progression of PTC by targeting IRS1. Besides that, miR-1271 blocked the epithelial-mesenchymal transition (EMT) and protein kinase B (AKT) pathway in PTC.

CONCLUSIONS

MiR-1271 inhibited the progression of PTC by targeting IRS1 and blocking EMT and AKT pathway.

Prognostic gene expression signature for high-grade serous ovarian cancer

BACKGROUND

Median overall survival (OS) for women with high-grade serous ovarian cancer (HGSOC) is ∼4 years, yet survival varies widely between patients. There are no well-established, gene expression signatures associated with prognosis. The aim of this study was to develop a robust prognostic signature for OS in patients with HGSOC.

PATIENTS AND METHODS

Expression of 513 genes, selected from a meta-analysis of 1455 tumours and other candidates, was measured using NanoString technology from formalin-fixed paraffin-embedded tumour tissue collected from 3769 women with HGSOC from multiple studies. Elastic net regularization for survival analysis was applied to develop a prognostic model for 5-year OS, trained on 2702 tumours from 15 studies and evaluated on an independent set of 1067 tumours from six studies.

RESULTS

Expression levels of 276 genes were associated with OS (false discovery rate < 0.05) in covariate-adjusted single-gene analyses. The top five genes were TAP1, ZFHX4, CXCL9, FBN1 and PTGER3 (P < 0.001). The best performing prognostic signature included 101 genes enriched in pathways with treatment implications. Each gain of one standard deviation in the gene expression score conferred a greater than twofold increase in risk of death [hazard ratio (HR) 2.35, 95% confidence interval (CI) 2.02-2.71; P < 0.001]. Median survival [HR (95% CI)] by gene expression score quintile was 9.5 (8.3 to -), 5.4 (4.6-7.0), 3.8 (3.3-4.6), 3.2 (2.9-3.7) and 2.3 (2.1-2.6) years.

CONCLUSION

The OTTA-SPOT (Ovarian Tumor Tissue Analysis consortium - Stratified Prognosis of Ovarian Tumours) gene expression signature may improve risk stratification in clinical trials by identifying patients who are least likely to achieve 5-year survival. The identified novel genes associated with the outcome may also yield opportunities for the development of targeted therapeutic approaches.

The effectiveness and safety of thromboprophylaxis in cancer patients based on Khorana score: a meta-analysis and systematic review of randomized controlled trials

INTRODUCTION

Cancer patients receiving chemotherapy are a high risk of VTE, yet the importance of thromboprophylaxis for cancer patients that are at high risk of developing VTE is still controversial.

AIM

To calculate the benefits and harms of thromboprophylaxis, compared to placebo, in ambulatory high-risk cancer patients that are receiving chemotherapy.

METHODS

We searched PubMed, Embase, Web of Science, the Cochrane Library, Cochrane Central Register of Controlled Trials, Chinese Biomedical Literature Database, WANFANG Data, Chinese National Knowledge Infrastructure and Chinese Scientific Journal Database for randomized controlled trials (RCTs) describing benefits and harms of thromboprophylaxis. Statistical analysis was performed using Stata software (version 15.1).

RESULTS

We included six studies, which contained a total of 3240 cancer patients with thromboprophylaxis and 2874 cancer patients without thromboprophylaxis. Thromboprophylaxis was effective in high-risk patients with two points or higher (RR 0.51, 95% CI 0.36-0.71, I² = 0.0%, P = 0.526). It was associated with an increase in bleeding events (RR 1.65, 95% CI 1.14-2.40, I² = 0.0%, P = 0.498) and was mainly efficient in reducing the risk of pulmonary embolism (RR 0.56, 95% CI 0.33-0.96, I² = 0.0%, P = 0.263). The risk of major (RR 1.85, 95% CI 0.87-3.94, I² = 0.0%, P = 0.888) and non-major (RR 1.59, 95% CI 0.96-2.62, I² = 16.3%, P = 0.303) bleeding showed no significant difference with or without thromboprophylaxis. There was no reduction in all-cause mortality with thromboprophylaxis (RR 0.95, 95% CI 0.78-1.18, I² = 22.0%, P = 0.277).

CONCLUSION

Thromoboprophylaxis is effective and safe in cancer patients that are at high risk for developing VTE with chemotherapy.

Mutation of Bdpaired induces embryo lethality in the oriental fruit fly, Bactrocera dorsalis

BACKGROUND

Pair-rule genes were identified and named for their role in segmentation in animal embryos. Paired, a homolog of mammalian PAX3, acts as one of several pair-rule genes and is key in defining the boundaries of future parasegments and segments during insect embryogenesis.

RESULTS

We cloned the paired gene from the oriental fruit fly, Bactrocera dorsalis, and then applied CRISPR/Cas9-mediated genome editing to investigate its physiological function in the embryonic stage of this pest. We identified one transcript for a paired homolog in B. dorsalis, which encodes a protein containing a Paired Box domain and a Homeobox domain. Phylogenetic analysis confirmed that the paired gene is highly conserved and the gene was highly expressed at the 12-14 h-old embryonic stage. Knock-out of Bdpaired led to lack of segment boundaries, cuticular deficiency, and embryonic lethality. Sequence analysis of the CRISPR/Cas9 mutants exhibited different insertion and deletions in the Bdpaired locus. In addition, the relative expression of Wingless (Wg) and Abdominal A (Abd-A) genes were significantly down-regulated in the Bdpaired mutant embryos.

CONCLUSION

These results indicate that Bdpaired gene is critical for the embryonic development of B. dorsalis, and could be a novel molecular target for genetic-based pest management practices to combat this serious invasive pest. © 2019 Society of Chemical Industry.

Four weeks of hypoxia training improves cutaneous microcirculation in trained rowers

Hypoxia training can improve endurance performance. However, the specific benefits mechanism of hypoxia training is controversial, and there are just a few studies on the peripheral adaptation to hypoxia training. The main objective of this study was to observe the effects of hypoxia training on cutaneous blood flow (CBF), hypoxia-inducible factor (HIF), nitric oxide (NO), and vascular endothelial growth factor (VEGF). Twenty rowers were divided into two groups for four weeks of training, either hypoxia training (Living High, Exercise High and Training Low, HHL) or normoxia training (NOM). We tested cutaneous microcirculation by laser Doppler flowmeter and blood serum parameters by ELISA. HHL group improved the VO(2peak) and power at blood lactic acid of 4 mmol/l (P(4)) significantly. The CBF and the concentration of moving blood cells (CMBC) in the forearm of individuals in the HHL group increased significantly at the first week. The HIF level of the individuals in the HHL group increased at the fourth week. The NO of HHL group increased significantly at the fourth week. In collusion, four weeks of HHL training resulted in increased forearm cutaneous blood flow and transcutaneous oxygen pressure. HHL increases rowers' NO and VEGF, which may be the mechanism of increased blood flow. The increased of CBF seems to be related with improving performance.

Symbiotic bacteria motivate the foraging decision and promote fecundity and survival of Bactrocera dorsalis (Diptera: Tephritidae)

Background

The gut bacteria of tephritid fruit flies play prominent roles in nutrition, reproduction, maintenance and ecological adaptations of the host. Here, we adopted an approach based on direct observation of symbiotic or axenic flies feeding on dishes seeded with drops of full diet (containing all amino acids) or full diet supplemented with bacteria at similar concentrations to explore the effects of intestinal bacteria on foraging decision and fitness of Bactrocera dorsalis.

Results

The results show that intestinal probiotics elicit beneficial foraging decision and enhance the female reproduction fitness and survival of B. dorsalis (symbiotic and axenic), yet preferences for probiotic diets were significantly higher in axenic flies to which they responded faster compared to full diet. Moreover, females fed diet supplemented with Pantoea dispersa and Enterobacter cloacae laid more eggs but had shorter lifespan while female fed Enterococcus faecalis and Klebsiella oxytoca enriched diets lived longer but had lower fecundity compared to the positive control. Conversely, flies fed sugar diet (negative control) were not able to produce eggs, but lived longer than those from the positive control.

Conclusions

These results suggest that intestinal bacteria can drive the foraging decision in a way which promotes the reproduction and survival of B. dorsalis. Our data highlight the potentials of gut bacterial isolates to control the foraging behavior of the fly and empower the sterile insect technique (SIT) program through the mass rearing.

ZB transposon and chicken vasa homologue (Cvh) promoter interact to increase transfection efficiency of primordial germ cells in vivo

1. In order to increase the efficiency of generating transgenic chicken, this trial focused on two points: primordial germ cells (PGCs）transfection in vivo and a germline-specific promoter.2. In order to transfect PGCs in vivo, two plasmids (pZB-CAG-GFP, pCMV-ZB）were co-injected into chicken embryos via the subgerminal cavity at Hamburger and Hamilton (HH) stage 2-3 or via blood vessel at HH stage 13-14. Results showed that the percentage of GFP+ embryos, viability and hatching rate of embryos injected at HH stage 13-14 were significantly higher than that at HH stage 2-3.3. Two plasmid transposon systems were used for chicken embryo micro-injections. The donor plasmid, with a green fluorescent protein (GFP) reporter gene, was mediated by the ZB transposon. The helper plasmid was a transposase expression vector driven by the promoter of the chicken vasa homologue (Cvh) gene or Human cytomegalovirus (CMV) promoter. Results showed that 60.98% of gonads in Cvh group expressed GFP, which was 52.50% higher than seen in the CMV group. Only gonad tissue from the Cvh group showed any GFP signal, whereas both gonads and other tissues in the CMV group showed green fluorescence.4. The data suggested that ZB transposon-mediated gene transfer was efficient for transfecting PGCs in vivo; the Cvh promoter drove the transposase gene specifically in the germline and increased the efficiency of germline transmission. Blood vessels injection at HH stage 13-14 may be a more efficient route for PGCs transfection in vivo.

Obesity in acute alcoholic hepatitis increases morbidity and mortality

BACKGROUND

Alcohol and obesity synergise to increase the risk of liver-related mortality. We examined the influence of adiposity on clinical outcomes in alcoholic hepatitis (AH) and the underlying inflammatory crosstalk between adipose tissue (AT) and the liver.

METHODS

A cohort of 233 patients with AH from the UK and USA provided data to analyse the effects of obesity in AH. Body mass index was corrected for the severity of ascites, termed cBMI. Inflammatory and metabolic profiling was undertaken by proteome analysis of human serum samples. The effect of alcohol on adipose tissue and CXCL11 expression was studied in 3 T3-derived adipocytes and in mice using the high-fat diet-plus-binge ethanol model.

FINDINGS

Obesity was common amongst patients with AH, seen in 19% of individuals. Obesity (HR 2.22, 95%CI 1.1-4.3, p = .022) and underweight (HR 2.38, 1.00-5.6, p = .049) were independently associated with mortality at 3 months. Proteome analysis demonstrated multiple metabolic and inflammatory factors differentially expressed in obese AH verse lean AH, with CXCL11 being the most elevated factor in obese AH. In vitro analysis of cultured adipocytes and in vivo analysis of mouse models showed that alcohol induced CXCL11 expression in AT, but not in liver.

INTERPRETATION

Obesity is common in AH and associated with a greater than two-fold increase in short-term mortality. Obese AH is associated with a different inflammatory phenotype, with the greatest elevation in CXCL11. These data confirm that adiposity is clinically important in acute alcohol-related liver disease and illustrate the adipose-liver inflammatory axis in AH. FUND: This work was supported in part by an EASL Sheila Sherlock Physician Scientist Fellowship. The funder played no role in gathering or analysing data or writing the manuscript. This paper presents independent research supported by the NIHR Birmingham Biomedical Research Centre at the University Hospitals Birmingham NHS Foundation Trust and the University of Birmingham. The views expressed are those of the author(s) and not necessarily those of the NHS, the NIHR or the Department of Health and Social Care.

Hierarchical spiral-scan trajectory for efficient scanning ion conductance microscopy

Scanning ion conductance microscopy (SICM) is an emerging technique for non-contact, high-resolution topography imaging, especially suitable for live cells investigation in a physiological environment. Despite its rapid development, the extended acquisition time issues of its typical hopping/backstep scanning mode still restrict its application for more fields. Herein, we propose a novel SICM scanning approach to effectively reduce the retract distance of existing hopping/backstep mode. In this approach, the SICM probe first gradually descends in the z-direction. Then by using Archimedes spiral trajectory, which has the advantage of higher angular velocity due to its continuous and smooth trajectory, the probe rapidly detects the highest point of the sample in the xy-plane in a layer-by-layer way. Further, the maximum height that decides the retrace distance of pipet in the detected region can be quickly achieved, avoiding a huge retrace distance usually adopted in the existing methods without any prior knowledge (sample height and steepness in the scanning region). Therefore, this new scanning method can greatly reduce the imaging time by minimizing the retrace height of each measurement point. Theoretical analysis is conducted to compare the imaging time of traditional and new method. And various factors in the new method that affect the imaging speed are analyzed. In addition, PDMS (polydimethylsiloxane) and biological samples (C2C12 cells) were imaged by SICM that was operated in the hopping mode, raster-based detecting and developed method with a single-barrel pipet, respectively. The experimental results suggest that the new method has a faster imaging speed than conventional scanning modes but does not sacrifice the imaging quality.

The efficacy of the Dietary Approaches to Stop Hypertension diet with respect to improving pregnancy outcomes in women with hypertensive disorders

BACKGROUND

The DASH (Dietary Approaches to Stop Hypertension) diet serves as a dietary pattern for the prevention and control of hypertension. The present study aimed to investigate whether the DASH diet can improve the outcomes of pregnancy with gestational hypertension (GH) and chronic hypertension.

METHODS

The current randomised controlled clinical trial was performed in 85 pregnant women diagnosed with GH and chronic hypertension between July 2015 and December 2017. The women were categorised into a control group (41 cases) and a DASH group (44 cases). Participants were followed until delivery. The clinical outcomes of mothers included gestational weeks of birth, delivery mode, postpartum haemorrhage and GH, as well as the incidence of pre-eclampsia during the second and third trimesters. Newborn measurements were collected by evaluating prematurity, birth weight, body length and neonatal Apgar score.

RESULTS

The incidence of pre-eclampsia, prematurity and low birth weight in the DASH group was lower than that in the control group (P < 0.05). Significant differences were also observed in gestational age at delivery and the newborn body length between the two groups (P < 0.05). We failed to find a significant difference in changes of delivery mode, postpartum haemorrhage, postpartum GH, mean birth weight and Apgar score (P > 0.05) between the two diets.

CONCLUSIONS

A DASH diet might comprise a potential strategy for improving the clinical outcomes in pregnant women with GH and chronic hypertension. Future robust clinical trials are warranted to corroborate these findings.