Application of bacteriophage φPaP11-13 attenuates rat Cutibacterium acnes infection lesions by promoting keratinocytes apoptosis via inhibiting PI3K/Akt pathway

Acne vulgaris caused by antibiotic-resistant Cutibacterium acnes (C. acnes) infection is difficult to treat conventionally. Phages have been suggested as a potential solution, but research on the mechanism of phage treatment is inadequate. This research investigates the underlying molecular mechanisms of phage φPaP11-13 attenuating C. acnes-induced inflammation in rat models. We found that rats infected with C. acnes had higher average ear thickness, greater enrichment of inflammatory cells as shown by hematoxylin-eosin (HE) staining, and fewer TUNEL (TdT-mediated dUTP Nick-End Labeling)-positive keratinocytes visualized by IF staining. Moreover, an increase of IGF-1 and IGF-1 receptor (IGF-1r) was detected using the immunohistochemical (IHC) staining method, Western blot (WB), and quantitative real-time PCR (qRT-PCR) when infected with C. acnes, which was decreased after the application of phage φPaP11-13. By applying the IGF-1 antibody, it was demonstrated that the severity of C. acnes-induced inflammation was relevant to the expression of IGF-1. Through WB and qRT-PCR, activation of the PI3K/Akt pathway and a down-regulation of the BAD-mediated apoptosis pathway were discovered after C. acnes infection. Subsequently, it was shown that the activation of the PI3K/Akt pathway against BAD-mediated apoptosis pathway was alleviated after applying phage φPaP11-13. Furthermore, applying the IGF-1r inhibitor, Pan-PI3K inhibitor, and Akt inhibitor reversed the changing trends of BAD induced by C. acnes and phage φPaP11-13. This study demonstrates that one of the critical mechanisms underlying the attenuation of acne vulgaris by phage φPaP11-13 is lysing C. acnes and regulating keratinocyte apoptosis via the PI3K/Akt signaling pathway.IMPORTANCECutibacterium acnes infection-induced acne vulgaris may cause severe physical and psychological prognosis. However, the overuse of antibiotics develops drug resistance, bringing challenges in treating Cutibacterium acnes. Bacteriophages are currently proven effective in MDR (multiple drug-resistant) Cutibacterium acnes, but there is a significant lack of understanding of phage therapy. This study demonstrated a novel way of curing acne vulgaris by using phages through promoting cell death of excessive keratinocytes in acne lesions by lysing Cutibacterium acnes. However, the regulation of this cell cycle has not been proven to be directly mediated by phages. The hint of ternary relation among "phage-bacteria-host" inspires huge interest in future phage therapy studies.

High temperature stress induced oxidative stress, gut inflammation and disordered metabolome and microbiome in tsinling lenok trout

Tsinling lenok trout (Brachymystax lenok tsinlingensis Li) is a species of cold-water salmon that faces serious challenges due to global warming. High temperature stress has been found to damage the gut integrity of cold-water fish, impacting their growth and immunity. However, limited research exists on the causal relationship between gut microbial disturbance and metabolic dysfunction in cold-water fish induced by high temperature stress. To address this gap, we conducted a study to investigate the effects of high temperature stress (24 °C) on the gut tissue structure, antioxidant capacity, gut microorganisms, and metabolome reactions of tsinling lenok trout. Our analysis using 16 S rDNA gene sequencing revealed significant changes in the gut microbial composition and metabolic profile. Specifically, the abundance of Firmicutes and Gemmatimonadetes decreased significantly with increasing temperature, while the abundance of Bacteroidetes increased significantly. Metabolic analysis revealed a significant decrease in the abundance of glutathione, which is synthesized from glutamate and glycine, under high temperature stress. Additionally, there was a notable reduction in the levels of adenosine, inosine, xanthine, guanosine, and deoxyguanosine, which are essential for DNA/RNA synthesis. Conversely, there was a significant increase in the abundance of D-glucose 6 P. Furthermore, high temperature stress adversely affects intestinal structure and barrier function. Our findings provide valuable insights into the mechanism of high temperature stress in cold-water fish and serve as a foundation for future research aimed at mitigating the decline in production performance caused by such stress.

Single Cell Analysis of Macrophage Heterogeneity and NK-Cell Exhaustion in Lewis Lung Cancer Xenograft Tumor

PURPOSE/OBJECTIVE(S)

Stereotactic body radiation therapy (SBRT) has attracted much attention because of its ability to stimulate anti-tumor immune response. However, the mechanism of SBRT reprogramming the tumor microenvironment remains to be elucidated.

MATERIALS/METHODS

Using Lewis lung carcinoma (LLC) xenograft mice model treated with SBRT (8Gy x 3F), multiplex assay was performed to measure serum chemokine levels, and single-cell RNA sequencing was performed to assess tumor microenvironment. The differential expression genes of each cell subcluster were identified by the "Find-All markers" function with default parameters provided by Seurat. Intercellular communication analysis was explored by using CellPhone DB package.

RESULTS

The majority of serum chemokines involved macrophage recruitment, including CCL3, CCL4, CCL8, and CCL20, were highly secreted at 7 days after SBRT. Single-cell RNA sequencing of 108,741 cells were contained from 6 mouse Lewis lung carcinoma samples (n = 3 tumors for SBRT, n = 3 tumors pooled for SHAM). Besides Lewis cancer cells, myeloid cells were 57.61% ,70.82% in Sham-irradiation (SHAM) and SBRT while NT and T cells were 20.50%, 7.81% in SHAM and SBRT, respectively. When compared with SHAM group, upregulation of Ccl3, Ccl4, Ccl8 chemokine genes were observed in cancer cells of SBRT group. Differential expression genes analysis showed high expression level of Ccl8 (Log2FC 2.54, p<0.01) in cluster of Mrc1+macrophage. The SBRT group consisted of more Ccl8+Mrc1+macrophages (proportion 36.28% for SBRT, 27.44% for SHAM) and exhausted NK cells (proportion 22.56% for SBRT, 13.70% for SHAM). More importantly, intercellular communication analysis revealed a potential communication network between Ccl8+Mrc1+macrophages and exhausted NK cells.

CONCLUSION

Our results provide a potential therapeutic strategy by disrupting Ccl8+ Mrc1+macrophages and NK-cell interaction to facilitate the stimulation of the anti-tumor immune response by SBRT.

High-Flux Neutron Generator Based on Laser-Driven Collisionless Shock Acceleration

A novel compact high-flux neutron generator with a pitcher-catcher configuration based on laser-driven collisionless shock acceleration (CSA) is proposed and experimentally verified. Different from those that previously relied on target normal sheath acceleration (TNSA), CSA in nature favors not only acceleration of deuterons (instead of hydrogen contaminants) but also increasing of the number of deuterons in the high-energy range, therefore having great advantages for production of high-flux neutron source. The proof-of-principle experiment has observed a typical CSA plateau feature from 2 to 6 MeV in deuteron energy spectrum and measured a forward neutron flux with yield 6.6×10^{7}  n/sr from the LiF catcher target, an order of magnitude higher than the compared TNSA case, where the laser intensity is 10^{19}  W/cm^{2}. Self-consistent simulations have reproduced the experimental results and predicted that a high-flux forward neutron source with yield up to 5×10^{10}  n/sr can be obtained when laser intensity increases to 10^{21}  W/cm^{2} under the same laser energy.

Intrathecal administration of botulinum toxin type a antagonizes neuropathic pain by countering increased vesicular nucleotide transporter expression in the spinal cord of chronic constriction injury of the sciatic nerve rats

Botulinum toxin type A (BoNT/A) induces direct analgesic effects in neuropathic pain by inhibiting the release of substance P, calcitonin gene-related peptide (CGRP) and glutamate. Vesicular nucleotide transporter (VNUT) was responsible for the storage and release of ATP in vivo, and one of the mechanisms underlying neuropathic pain is VNUT-dependent release of extracellular ATP from dorsal horn neurons. However, the analgesic effect of BoNT/A by affecting the expression of VNUT remained largely unknown. Thus, in this study, we aimed to elucidate the antinociceptive potency and analgesic mechanism of BoNT/A in chronic constriction injury of the sciatic nerve (CCI) induced neuropathic pain. Our results showed that a single intrathecal injection of 0.1 U BoNT/A seven days after CCI surgery produced significant analgesic activity and decreased the expression of VNUT in the spinal cord of CCI rats. Similarly, BoNT/A inhibited the CCI-induced increase in ATP content in the rat spinal cord. Overexpression of VNUT in the spinal cord of CCI-induced rats markedly reversed the antinociceptive effect of BoNT/A. Furthermore, 33 U/mL BoNT/A dramatically reduced the expression of VNUT in pheochromocytoma (PC12) cells but overexpressing SNAP-25 increased VNUT expression in PC12 cells. Our current study is the first to demonstrate that BoNT/A is involved in neuropathic pain by regulating the expression of VNUT in the spinal cord in rats.

Small molecule-mediated rapid maturation of human induced pluripotent stem cell derived cardiomyocytes

Funding Acknowledgements

Type of funding sources: Other. Main funding source(s): Gravitation Program “Materials Driven Regeneration” by the Netherlands Organization for Scientific Research (RegmedXB #024.003.013) and the Marie Skłodowska-Curie Actions (Grant agreement RESCUE #801540). The EU-funded project BRAV3 (H2020, ID:874827)

Background

Human-induced pluripotent stem cell (iPSC)-derived cardiomyocytes (iPSC-CMs) do not display all hallmarks of mature human primary cardiomyocytes: the ability to use fatty acids as an energy source, high mitochondrial mass, increased nuclei polyploidism, synchronized electrical conduction, and forceful contractions. Instead, their phenotype is similar to immature cardiomyocytes in the late fetal stage. This immaturity represents a bottleneck to their application in 1) disease modeling – as most cardiac (genetic) diseases have a middle-age onset – and 2) clinical use, where integration and functional coupling are key. So far, the mainly used methods to enhance iPSC-CM maturation include prolonged time-in-culture, 3D culture, cyclic mechanical stretch, and electrical stimulation with specialized media. However, these protocols are laborious, costly, and not easily scalable.

Methods

In this study, we developed a simple, low cost, and rapid protocol using two peroxisome proliferator-activated receptor gamma coactivator 1-alpha (PPARGC1A/PGC-1α) activating small molecules: Asiatic Acid (AA) and GW501516 (GW) to promote cardiomyocyte maturity by inducing a metabolic switch to fatty acid utilization and increased mitochondrial biogenesis.

Results

Monolayers of iPSC-CMs were incubated with AA and GW every other day for 10 days resulting in increased expression of fatty acid-metabolism-related genes (5 and 10-fold increase in CPT1B gene expression, respectively), mitochondria biogenesis (protein expression of ATP5A) and fusion (50 and 100-fold increase in OPA1 gene expression, respectively). In addition, AA treated iPSC-CMs responded in the seahorse mitochondria stress test more rapidly to an artificial increase in mitochondrial activity and showed a higher flexibility in substrate utilization in the seahorse stress test. A more mature electrophysiological functionality was shown by increased ion channel gene expression (KCNA4, SCN5A, GJA1, CACNA1C, and SCN1B) and enhanced synchronous contraction in treated samples. Moreover, maturation was further shown by increased sarcomeric gene expression (5 and 7-fold increase in TNNI3 in AA and GW respectively) and nuclear polyploidism (&gt;4N fold 2.16 and 1.48-fold increase in AA and GW respectively).

Conclusions

Collectively, these findings show that AA and GW trigger a metabolic switch and induce extensive maturation of iPSC-CMs, providing a rapid and cost-effective method to obtain iPSC-CMs that more closely resemble their adult counterparts.

E2F7/8 is involved in cardiomyocyte polyploidy but does not affect myocardial reperfusion injury recovery

Funding Acknowledgements

Type of funding sources: Other. Main funding source(s): CSC fellowship

Background

Polyploidy cells consist of more than two complete sets of homologous chromosomes. Although a characteristic feature of cardiomyocytes and observed in all mammalian species, its molecular mechanism and biological functions are still unknown. Cardiomyocytes polyploidy in rodents occurs mainly through incomplete cytokinesis and increases with age. Studies have demonstrated that E2F7/8 transcription factors are key regulators of polyploidy in the liver and pancreas, however, it remains unclear if E2F7/8 control the generation of polyploidy cardiomyocytes and what the functional consequence is post-myocardial infarction (MI).

Methods

By using a tamoxifen inducible Cre/LoxP approach in new-born mice, we deleted E2F7/8 transcription factors ubiquitously and evaluated the biological significance of postnatal E2F7/8 loss. Mice underwent myocardial ischemia reperfusion injury (IRI) and heart function was assessed by 4D-echocardiography. Cardiomyocyte nucleus polyploidy was measured by FACS and microscope.

Results

Deficiency of E2F7/8 significantly suppress cardiomyocyte mononucleated and multinucleated polyploidy, as well as dramatically decreased hepatocytes polyploidy. E2F7/8 defect also led to a decrease in cardiac stress related marker lever such as ANP, BNP, MMP2, β-MHC/α-MHC and an increase in CD31 expression level. Surprisingly, E2F7/8 deletion did not have impact on cardiac function and dimensions post-IRI.

Conclusion

In summary, we identified that E2F7/8 activity is involved in the cellular polyploidy in the heart but did not affect myocardial function after myocardial injury.

Myocardial tissue slices for modeling of the human PLN p.Arg14del associated cardiomyopathy

Funding Acknowledgements

Type of funding sources: Public grant(s) – National budget only. Main funding source(s): NWO - The Dutch Research Council

Background

Current in vivo preclinical models lack the predictability of the clinical efficacy resulting in a high dropout rate of therapeutic candidates. Advanced human-based models are required to bridge this gap and indicate the potential of novel therapeutic approaches[1].  Myocardial tissue slices are an in vitro model that recapitulates the native multicellular architecture of the heart. This allows for modeling cellular processes in a macroscopic context entailing great promise. The most common cardiomyopathy-related mutation in the Netherlands is the loss of arginine at position 14 (p.Arg14del) in the phospholamban protein (PLN). PLN is a critical regulator of calcium cycling and contractility in the heart. The p.Arg14del mutation results in a super inhibition of SERCA2a and thus aberrant calcium handling and reduced contractile force. Mice models harbouring the PLN p.Arg14del do not completely recapitulate the human manifestation mainly due to the difference between species; heart rate, Calcium-cycling and ion properties, and different myosin heavy chain isoforms, showing the unmet need for a human-based model[2,3].

Methods & Results

300 µm thick viable myocardial tissue were sectioned from a PLN p.Arg14del patient’s left ventricle. Although the myocardial tissue slices were kept alive for eight days in static culture, these conditions initiated cell death and dedifferentiation. The tissue slices show the greatest resemblance to the intact architecture of the in vivo human heart, it is the most relevant model for viral transduction in the human heart, and proof-of-principle of this is performed. Myocardial tissue slices of a PLN p.Arg14del patient retain the structural phenotype shown by the fibrofatty deposition. Similarly, functional patient characteristics, aberrant calcium handling, and reduced contractile force are preserved.

Conclusion

Myocardial tissue slices recapitulate the (patho)physiology of the heart, as shown here with the PLN p.Arg14del case. However, the static culture conditions induce remodeling of the heart and thus only allow for acute measures in the native heart. To prolong the period that the slices recapitulate the native heart, culture conditions should mimic the environment of the heart. The tissue slices allow for a currently unmet need to modulate the complex architecture of the human heart with e.g. novel delivery tools or therapeutic interventions. All in all, myocardial tissue slices are a promising model that can give novel insights into the physiology of the human heart, and therapeutic intervention on induced or genetic cardiomyopathies.

Effect of Microgroove Structure in PDMS-Based Silicone Implants on Biocompatibility

Capsule and capsule contracture around implants are important concerns in a clinic. The physical topology of the material surface regulates the formation of the capsule, but the specific regulatory mechanism is unclear. In this study, four types of silicone implant materials with different microgroove structures (groove depths of 10 and 50 μm and widths of 50 and 200 μm) were constructed using lithography to form different gradient surface topologies. Mass spectrometry, Cell Counting Kit-8, 5-ethynyl-2′-deoxycytidine (EdU), enzyme-linked immunosorbent assay, western blot, immunofluorescence, and immunohistochemistry were used to explore the changes in protein adsorption, cell adhesion, cell proliferation, and collagen deposition on the surface of the materials. At the same time, RNA-seq was used to detect transcriptome differences caused by different structures. Furthermore, collagen deposition and capsule formation were observed in the rats. The groove structure was observed to significantly increase the surface roughness of the material. The deeper groove and the narrower width of the polydimethylsiloxane would increase the surface roughness of the material and the surface water contact angle but reduce the total amount of adsorbed protein in the first two hours. In vitro cell experiments revealed that microtopology affected cell proliferation and adhesion and regulated collagen secretion. Further analysis indicated the deeper and narrower groove (group 50–50) on the surface of the material caused more evident collagen deposition around the material, forming a thicker envelope. Surface roughness of the material was thus related to collagen deposition and envelope thickness. The thickness of the envelope tissue around smooth materials does not exceed that of the materials with surface roughness. In conclusion, the narrower and deeper grooves in the micron range exhibited poor histocompatibility and led to formation of thicker envelopes around the materials. The appropriate grooves can reduce envelope thickness.

MicroRNA-214-3p Ameliorates LPS-Induced Cardiomyocyte Injury by Inhibiting Cathepsin B

Myocardial injury is a common complication of sepsis. MicroRNA (miRNA) miR-214-3p is protective against myocardial injury caused by sepsis, but its mechanism in lipopolysaccharide (LPS)- induced cardiomyocyte injury is still unclear. An AC16 cell injury model was induced by LPS treatment. Cell Counting Kit-8 and flow cytometry assay showed decreased cell viability and increased apoptosis in LPS-treated AC16 cells. The levels of caspase- 3, Bax, atrial natriuretic peptide (ANP), brain natriuretic peptide (BNP), myosin 6 (Myh6), myosin 7 (Myh7), reactive oxygen species (ROS), and malondialdehyde (MDA) were increased in LPS-treated AC16 cells, but the levels of Bcl-2 and superoxide dismutase (SOD) were decreased. MiR-214-3p was down-regulated and cathepsin B (CTSB) was upregulated in LPS-treated AC16 cells. At the same time, miR-214-3p could target CTSB and reduce its expression. We also found that a miR-214-3p mimic or CTSB silencing could significantly reduce LPSinduced apoptosis, decrease ROS, MDA, caspase-3, and Bax and increase SOD and Bcl-2. CTSB silencing could significantly reduce ANP, BNP, Myh6, and Myh7 in LPS-treated AC16 cells. The effects of CTSB silencing were reversed by a miR-214-3p inhibitor. In summary, miR-214-3p could inhibit LPSinduced myocardial injury by targeting CTSB, which provides a new idea for myocardial damage caused by sepsis.

Onset of inverse magnetic energy transfer in collisionless turbulent plasmas

Inverse magnetic energy transfer from small to large scales is a key physical process for the origin of large-scale strong magnetic fields in the universe. However, so far, from the magnetohydrodynamic perspective, the onset of inverse transfer is still not fully understood, especially the underlying dynamics. Here, we use both two-dimensional and three-dimensional particle-in-cell simulations to show the self-consistent dynamics of inverse transfer in collisionless decaying turbulent plasmas. Using the space filtering technique in theory and numerical analyses, we identify magnetic reconnection as the onset and fundamental drive for inverse transfer, where, specifically, the subscale electromotive force driven by magnetic reconnection do work on the large-scale magnetic field, resulting in energy transfer from small to large scales. The mechanism is also verified by the strong correlations in locations and characteristic scales between inverse transfer and magnetic reconnection.

Downregulated long noncoding RNA LUCAT1 inhibited proliferation and promoted apoptosis of cardiomyocyte via miR-612/HOXA13 pathway in chronic heart failure

OBJECTIVE

Long non-coding RNAs (lncRNAs) have been reported to play important roles in numerous kinds of cardiovascular disease, including chronic heart failure (CHF). In this study, we mainly focused on investigating the potential roles of lncRNA LUCAT1 patients with CHF.

PATIENTS AND METHODS

RT-PCR was used to detect the expressions of LUCAT1 and miR-612 in serum samples of CHF patients (n=60) and healthy volunteers. Relationships between the expressions of LUCAT1 and miR-612, LUCAT1 and overall survival (OS) were analyzed using the Kaplan-Meier method. Si-LUCAT1 and miR-612 mimic were constructed and respectively transfected into AC16 cells to explore the functions of LUCAT1 and miR-612. Cell proliferation abilities were detected by CCK-8 assay AC16 cells. Cell apoptotic rates were measured by flow cytometry (FACS) analysis. Western blot (WB) was performed to detect the protein levels of HOXA13, Bcl-2, Bax, Bad and Cleaved Caspase3. In addition, luciferase gene reporter assay was used to prove the relationships between LUCAT1 and miR-612, miR-612 and HOXA13.

RESULTS

Firstly, we found that LUCAT1 was decreased for 1.7 folds in CHF patients, which was correlated with poor prognosis patients. LUCAT1 repression inhibited cell proliferation and promoted cell apoptosis in human cardiomyocyte cell line AC16 cells. Furthermore, we found that miR-612 was increased for 2.0 folds in CHF patients, which was negatively interacted with LUCAT1 expression. Luciferase gene reporter assay demonstrated that LUCAT1 could directly bind with miR-612 in AC16 cells. Moreover, miR-612 overexpression also inhibited cell proliferation and promoted cell apoptosis in AC16 cells. Luciferase reporter assay indicated that miR-612 could directly target at HOXA13 in AC16 cells, which was associated with cell proliferation and apoptosis. Finally, miR-612 inhibitor was transfected into AC16 cells with si-LUCAT1. The results showed that the inhibited cell proliferation and promoted cell apoptosis were reversed, which confirmed that LUCAT1 repression inhibited cell proliferation and promoted apoptosis via miR-612/HOXA13 axis in CHF patients.

CONCLUSIONS

According to the above results, our study revealed that LUCAT1 was decreased in CHF patients, which was correlated with poor prognosis of CHF patients. Furthermore, the downregulation of LUCAT1 inhibited cell proliferation and promoted cell apoptosis via targeting miR-612/HOXA13 axis. Our results elucidated a potential mechanism underlying cardiomyocyte apoptosis, which might be used as a promising prognostic marker and a potential target for CHF patients.

Structure and thermal properties of beeswax-based oleogels with different types of vegetable oil

Beeswax-based oleogels with different types of vegetable oil, including camellia oil (CO), soybean oil (SO), sunflower oil (SFO), or flaxseed oil (FO), were prepared and their structure and thermal properties were evaluated. The critical concentration of oleogel obtained from each of CO, SO, and SFO at 25 °C was 3% (w/w), and that from FO was 4%. Thermal measurements revealed similar thermodynamic curves for oleogels in different lipid phases. X-Ray diffraction showed orthorhombic perpendicular subcell packing and characteristic peaks of the β’ form. Furthermore, a morphology analysis of the crystals showed that they were needle shaped. Fourier transform-infrared spectra revealed that beeswax-based oleogels were formed via non-covalent bonds and may be stabilized with physical entanglements. The oleogels showed oil type-dependent oxidative abilities, but they were all stable and showed no obvious changes in peroxide value during 90 days of storage at 5 °C.

Oscillatory surface deformation of paramagnetic rare-earth solutions driven by an inhomogeneous magnetic field

The deformation of the free surface of a paramagnetic liquid subjected to a nonuniform magnetic field is studied. A transient deformation of the surface caused by the interplay of gravity, magnetic field, and surface tension is observed when a permanent magnet is moved vertically downward to the free surface of the liquid. Different concentrations of rare-earth-metal salt (DyCl_{3}) are used and different magnet velocities are studied. The deformation of the interface is followed optically by means of a microscope and recorded with a high-speed camera. The experimental results are compared and discussed with complementary numerical simulations. Detailed results are given for the static shape of the deformed surface and the temporal evolution of the surface deformation below the center of the magnet. The frequency of the surface oscillations is found to depend on the concentration of the salt and is compared with analytical findings. Finally, a potential application of the effects observed is presented.

Improvement of gibberellin production by a newly isolated Fusarium fujikuroi mutant

AIMS

To obtain and investigate the potential mechanism for GA₃ production in Fusarium fujikuroi GA-251, a high GA₃ producer.

METHODS AND RESULTS

Fusarium fujikuroi IMI 58289 was bred with Cobalt-60 (⁶⁰ Co) radiation and lithium chloride treatment. The best mutant strain GA-251 was obtained for the subsequent optimization of fermentation conditions. The yield of GA₃ by GA-251 was 2100 mg l^-1 , while the wild-type strain was 100 mg l^-1 , which is a 21-fold increase in the yield. To elucidate the mechanism of high GA₃ yield of GA-251, the genome was sequenced and compared with wild-type strain IMI 58289. The results showed 2295 single nucleotide polymorphisms, 1242 small indels and 30 structural variants. These mutations were analysed and enriched in the MAPK signalling pathway, the mRNA surveillance pathway and endocytosis. The potential reasons for the improved GA₃ biosynthesis were investigated.

CONCLUSIONS

The potential mechanism of high GA₃ yield was attributed to endocytosis pathway and histone modification proteins family.

SIGNIFICANCE AND IMPACT OF THE STUDY

A mutant strain GA-251 in this work that could potentially be utilized in the industrial yield of GA₃ . The comparative genome analysis would shed light onto the mechanism of yield improvement and be a theoretical guide for further metabolic engineering.

Aspartate β-hydroxylase disrupts mitochondrial DNA stability and function in hepatocellular carcinoma

The mechanism of aberrant mitochondrial genome and function in hepatocellular carcinoma (HCC) remains largely unknown. Our previous study demonstrated an increased expression of aspartate β-hydroxylase (ASPH) in HCC tissues, which was associated with tumor invasiveness and a worse prognosis. Currently, we unexpectedly observed the presence of ASPH in purified mitochondrial protein fraction. In addition, immunostaining of both exogenously and endogenously expressed ASPH showed a colocalization with mitochondrial biomarkers. This study aimed to investigate whether the mitochondrial ASPH is involved in mitochondrial malfunction in HCC. Our results showed that ASPH overexpression in HCC tissues was correlated with decreased copy numbers of displacement loop (D-loop) and NADH dehydrogenase subunit 1 (ND-1) and enhanced D-loop mutation, suggesting the disrupted mitochondrial DNA (mtDNA) stability. The reduced mtDNA copy numbers were associated with aggressive clinicopathological features of HCC. The loss of mtDNA integrity induced by enforced expression of ASPH was accompanied with mitochondrial dysfunction, which was characterized by the aberrant mitochondrial membrane potential, decreased ATP generation and enhanced reactive oxygen species. In contrast, knocking down ASPH by siRNA in HCC cell lines showed the opposite impact on mtDNA integrity and function. Mass spectrometry and co-immunoprecipitation further identified that ASPH interacted with histone H2A member X (H2AX). ASPH overexpression diminished the interaction between H2AX and mitochondrial transcription factor A (mtTFA), an important DNA-binding protein for mtDNA replication, which then reduced the binding of mtTFA to D-loop region. Collectively, our results demonstrate that ASPH overexpression disrupts the mtDNA integrity through H2AX-mtTFA signal, thereby affecting mitochondrial functions in HCC.

Preparation and evaluation of cefquinome-loaded gelatin microspheres and the pharmacokinetics in pigs

Cefquinome (CEF) is widely used for veterinary clinical applications because of its broad spectrum and high efficiency. However, frequent administrations are required due to its short elimination half-life. In this study, cefquinome sulfate gelatin microspheres (CEF-GMS) were prepared as a sustained-release formulation using emulsion chemical cross-linking technique. Physical properties, stability, sustained-release property in vitro, and pharmacokinetics in pigs were assessed. The morphology of CEF-GMS showed a good sphericity with porous structure on the surface, and the mean diameter was 8.80 ± 0.78 μm, with 90.60 ± 3.98% of the total in the range of 5-20 μm. There were no significant changes of all estimated indexes in the stability tests. In vitro drug release study showed that the release of CEF from CEF-GMS was much slower than that from crude CEF in a release medium. Pharmacokinetic characteristics were evaluated following intramuscular administration of CEF-GMS or Cefquinome sulfate injection (CEF-Inj) in pigs at a dosage of 4 mg CEF/kg body weight. The plasma drug concentration-time data of CEF-GMS and CEF-Inj were both best fitted by two-compartment models with first-order absorption, and the elimination half-life of CEF-GMS was almost 10 times that of CEF-Inj. Overall, CEF-GMS might be used as a sustained-release formulation of CEF for veterinary clinical applications.

Patients with HBV-related acute-on-chronic liver failure have increased concentrations of extracellular histones aggravating cellular damage and systemic inflammation

Acute-on-chronic liver failure (ACLF) is the most common type of liver failure and associated with grave consequences. Systemic inflammation has been linked to its pathogenesis and outcome, but the identifiable triggers are absent. Recently, extracellular histones, especially H4, have been recognized as important mediators of cell damage in various inflammatory conditions. This study aimed to investigate whether extracellular histones have clinical implications in patients with hepatitis B virus (HBV)-related ACLF. One hundred and twelve patients with HBV-related ACLF, 90 patients with chronic hepatitis B, 88 patients with HBV-related liver cirrhosis and 40 healthy volunteers were entered into this study. Plasma histone H4 levels, cytokine profile and clinical data were obtained. Besides, patient's sera were incubated overnight with human L02 hepatocytes or monocytic U937 cells in the presence or absence of antihistone H4 antibody, and cellular damage and cytokine production were evaluated. We found that plasma histone H4 levels were greatly increased in patients with ACLF as compared with chronic hepatitis B, liver cirrhosis and healthy control subjects and were significantly associated with disease severity, systemic inflammation and outcome. Notably, ACLF patients' sera incubation decreased cultured L02 cell integrity and induced profound cytokine production in the supernatant of U937 cells. Antihistone H4 antibody treatment abrogated these adverse effects, thus confirming a cause-effect relationship between extracellular histones and organ injury/dysfunction. The data support the hypothesis that the increased extracellular histone levels in ACLF patients may aggravate disease severity by inducing cellular injury and systemic inflammation. Histone-targeted therapies may have potentially interventional value in clinical practice.

Construction and identification of a model for HJURP gene defect expression in human embryo villus cells

OBJECTIVES

To construct a lentiviral vector for RNA interference (RNAi) of the HJURP gene and to identify the silencing efficiency in the human embryo villus cells and to provide a human embryo villus cells multiplication and chromosome segregation.

MATERIALS AND METHODS

In accordance with the study, three specific sequences of siRNA targeting HJURP gene were designed, synthesized, then the complementary DNA containing both sense and antisense oligonucleotides of the targeting sequences were annealed and inserted into the lentiviral vector.The correct clonings were confirmed by PCR and sequencing. The most effective recombinant lentivirus vector was screened, and the recombinant plasmids with the lentivirus packaging mixes were co-transfected into 293T cells to obtain packaged lentivirus particles. Then viral titer was determined. The silencing efficiency of target gene in human embryo villus cells was detected by Real-Time PCR.

RESULTS

DNA sequencing showed that the shRNA sequence was successfully inserted into the lentivirus vector. The recombinant lentiviral vector was successfully transfected into 293T cells. The recombinant lentivirus had a titer of 108 PFU/ml. After silencing HJURP gene in human embryo villus cells, the expression level of HJURP mRNA decreased significantly and the RNAi efficiency was greater than 70%.

CONCLUSION

A lentiviral shRNA expression vector targeting the HJURP gene was successfully constructed and may effectively silence the target gene at a cellular level, which provides a experimental model for the influence of HJURP gene expressing inhibition on human embryo villus cells multiplication and chromosome segregation.

Understanding hydraulic fracturing: a multi-scale problem

Despite the impact that hydraulic fracturing has had on the energy sector, the physical mechanisms that control its efficiency and environmental impacts remain poorly understood in part because the length scales involved range from nanometres to kilometres. We characterize flow and transport in shale formations across and between these scales using integrated computational, theoretical and experimental efforts/methods. At the field scale, we use discrete fracture network modelling to simulate production of a hydraulically fractured well from a fracture network that is based on the site characterization of a shale gas reservoir. At the core scale, we use triaxial fracture experiments and a finite-discrete element model to study dynamic fracture/crack propagation in low permeability shale. We use lattice Boltzmann pore-scale simulations and microfluidic experiments in both synthetic and shale rock micromodels to study pore-scale flow and transport phenomena, including multi-phase flow and fluids mixing. A mechanistic description and integration of these multiple scales is required for accurate predictions of production and the eventual optimization of hydrocarbon extraction from unconventional reservoirs. Finally, we discuss the potential of CO2 as an alternative working fluid, both in fracturing and re-stimulating activities, beyond its environmental advantages.This article is part of the themed issue 'Energy and the subsurface'.

The use of expanded polytetrafluoroethylene in depressed deformities of the face

Expanded polytetrafluoroethylene (ePTFE) has been extensively used for facial soft tissue augmentation procedures, and is regarded as safe and reliable and suitable as a permanent implant. This implant is generally used in the lower third of the face for lips filling, nasal augmentation, nasolabial folds and chin augmentation, and rarely for congenital or acquired depressed deformities of the face. The aim of the present study was to assess the effects of ePTFE in congenital or acquired depressed deformities of the face. From September, 2008 to January, 2014, 26 patients were implanted with the material ePTFE to correct depressed deformities of the face. The average age at operation was 23.2 years, with a range of 17-45 years. The depressed deformities were lateralized. The follow-up period was 6-18 months (average 9 months). The etiologies of the depressed deformities included stable hemifacial atrophy (3 cases), craniofacial microsomia (13 cases), bony depression after trauma (8 cases), and other unclear reasons (2 cases). The operations were performed under local anesthesia. ePTFE was inserted in different tissue planes that varied among the different subanatomical areas in the face: beneath the superficial temporal fascia in the temporal area, and on the surface of the superficial musculoaponeurotic system in the zygomatic area, cheek and mandibular area. All of the patients were followed up. Most of the patients [25 of 26 patients (96.2%)] were satisfied with the results, while 1 patient (3.8%) was not satisfied for incomplete correction of the depressed deformity. In conclusion, aside from lipofilling and a free flap transfer, the results showed that ePTFE was an alternative treatment for facial depressed deformity.

Cell-based evaluation of a novel Dictyophora indusiata polysaccharide against oxidative-induced erythrocyte hemolysis

The protective effect of a polysaccharide from Dictyophora indusiata(DP1)against oxidative hemolysis was comprehensively evaluated. The 2, 2-azobis (2-amidino-propane) dihydrochloride (AAPH)-induced erythrocyte hemolysis assay showed that DP1 exhibited excellent anti-hemolytic activity(87.4% hemolysis suppression ratio at 20 nmol/mL). Also, the formation of conjugated diene induced by cupric chloride (CuCl2) in plasma was significantly inhibited by DP1. Besides, DP1 could effectively inhibit AAPH-induced overproduction of reactive oxygen species (81.5% inhibition at 20 nmol/mL) and alleviated the enhancement of intracellular antioxidant enzymes including superoxide dismutase(SOD), glutathione peroxidase (GPX) and catalase (CAT) activities. Also, the malondialdehyde (MDA) formation caused by oxidative stress was suppressed by 57.0% at DP1 concentration of 20 nmol/mL. Taken together, the possible intracellular antioxidant detoxifying mechanism of DP1 was probably via preserving the activities of the antioxidant enzymes (SOD, GPx and CAT) as well as inhibiting lipid peroxidation, and thus alleviated erythrocytes oxidation and plasma oxidation.

Effects of whole-body vibration training with quadriceps strengthening exercise on functioning and gait parameters in patients with medial compartment knee osteoarthritis: a randomised controlled preliminary study

OBJECTIVE

To compare the effects of whole-body vibration training (WBVT) with quadriceps strengthening exercise (QSE) with QSE alone on functioning and gait parameters in patients with medial compartment knee osteoarthritis.

DESIGN

Randomised controlled preliminary study.

SETTING

Department of Rehabilitation Medicine, West China Hospital, Chengdu, Sichuan, People's Republic of China.

SUBJECTS

Thirty-nine patients with medial compartment knee osteoarthritis.

INTERVENTIONS

Participants were assigned at random to one of two groups.

MAIN MEASURES

Visual analogue scale (VAS) for pain, Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), timed up and go test (TUG), 6-minute walk distance test (6MWD), and three-dimensional gait analysis during level walking at baseline, 12 weeks and 16 weeks (follow-up).

RESULTS

Compared with baseline, significant improvements in VAS, all WOMAC scales, TUG, 6MWD and all spatiotemporal parameters were seen in both the WBVT+QSE group and the QSE alone group at 12 and 16 weeks. However, the WBVT+QSE group showed greater improvements than the QSE alone group in WOMAC scales (physical function), TUG, 6MWD and cadence at 12 weeks. No differences were found between the WBVT+QSE and QSE alone groups in VAS, WOMAC scales (pain, stiffness), kinematic and kinetic gait parameters, and other spatiotemporal parameters at 12 weeks and 16 weeks.

CONCLUSION

Over a 3-month period, WBVT in combination with QSE improved symptoms, physical function and spatiotemporal parameters in patients with medial compartment knee osteoarthritis, and led to greater improvement than QSE alone in WOMAC scales (physical function), TUG, 6MWD and cadence.

Repression of TIF1γ by SOX2 promotes TGF-β-induced epithelial-mesenchymal transition in non-small-cell lung cancer

TIF1γ is a novel regulator of transforming growth factor (TGF)-β/Smad signaling. Our previous studies show that dysregulated expression of transcriptional intermediary factor 1 γ (TIF1γ) and abnormal TGF-β/Smad signaling are implicated in non-small-cell lung cancer (NSCLC) separately. However, how TIF1γ contributes to NSCLC by controlling TGF-β/Smad signaling is poorly understood. Here, we investigated the mechanistic role of TIF1γ in TGF-β-induced epithelial-mesenchymal transition (EMT), as well as a link between TIF1γ and SOX2 in NSCLC. We show that TIF1γ is a downstream target of SOX2 in NSCLC cells. SOX2 overexpression negatively regulated TIF1γ promoter activity and thereby attenuated TIF1γ mRNA and protein expression levels; SOX2 knockdown significantly enhanced TIF1γ promoter activity and augmented TIF1γ expression. Moreover, TIF1γ mRNA expression was downregulated in human NSCLC tissues and negatively correlated with SOX2 protein, which was upregulated in NSCLC tissues. Importantly, knockdown of TIF1γ or SOX2 overexpression augmented SMAD4 (human Mad (mothers against decapentaplegic)-related homologous protein 4)-dependent transcriptional responses, and enhanced TGF-β-induced EMT and human NSCLC cell invasion; knockdown of SOX2 impaired TGF-β-induced EMT and NSCLC cell invasion. In an in vivo model of metastasis, knockdown of TIF1γ promotes NSCLC cell metastasis. In addition, our data suggested that TIF1γ inhibited TGF-β-induced EMT through competing with SMAD4 in NSCLC cells. Taken together, our findings reveal a new mechanism by which SOX2-mediated transcription repression of TIF1γ promotes TGF-β-induced EMT in NSCLC.

Contribution of glutathione S-transferase gene polymorphisms to development of skin cancer

BACKGROUND

Glutathione S-transferase (GST) family genes are of vital importance in maintaining cellular defence systems, protecting cells against the toxic effects of reactive oxygen produced during the synthesis of melanin, and detoxifying environmental mutagens and chemical or synthetic drugs. As no previous meta-analyses have examined the association of polymorphisms at GSTT1, GSTP1 Ile105Val with skin cancer risk and independently published studies have produced inconsistent conclusions, we were promoted to estimate the associations in the largest study to date.

METHODS

Computer-assisted searches were carried out to systematically identify the studies of GST polymorphisms and skin cancer. The eligibility of studies was evaluated following the requirements of inclusion criteria. Risk of skin cancers (OR and 95% CI) was assessed with the fixed or random effects meta-analysis.

MAJOR FINDINGS

The fixed effects meta-analysis of 15 studies suggested no overall association between GSTT1 null and skin cancer. Nor was there a significant association in any subgroup. However, in the stratified analysis by histologic type for GSTP1 Ile105Val, we found 1.56 times higher risk of malignant melanoma (MM) among people with the 105-Val/Val genotype (Val/Val vs. Ile/Ile: OR = 1.56, 95% CI = 1.05-2.32, pheterogeneity = 0.584).

CONCLUSIONS

These statistical data demonstrate that Ile105Val polymorphism of the GSTP1 gene may have genetic contribution to the development of skin cancer, MM in particular.

Retrospective analysis of factors affecting the efficacy of surgical treatment of the scar

AIM

The scar is a major problem in the medical profession. Its timely treatment is very important for the better outcome of the scar treatment and for the improvement of the life quality of the patients. The aim of this study was retrospectively analyzed the epidemiological characteristics affecting the efficacy of the scar surgical treatment of the people in the western part of China.

METHODS

Total 414 scar cases were retrospectively analyzed to clarify the epidemiological characteristics and the factors affecting the scar surgical treatment efficacy. The factors included were sex, age, area distribution, treatment seasons, injury sites, injury causes, and the time from scarring to the surgical treatment. All scar cases were surgically treated with the repairing technology including skin graft, flap and soft tissue dilation.

RESULTS

There were 206 males and 208 females with the average age 20.53±12.9 years (age range 1-68 years). The patient proportions in the age groups of 0-20, 21-40 and >40 years were 61.4% (254 cases), 29.2% (121 cases), and 9.4% (39 cases) respectively. The patient's attendance rate reached the highest during the summer and winter. Most patients were from the rural areas with an increasing tendency each year. The burn scars were the most abundant and the injury sites were mostly the head and face. Univariate analysis showed that the time from scarring to the surgical treatment and the injury sites were significantly influenced the scar surgical treatment efficacy. Logistic regression analysis demonstrated that the injured sites of the head and face significantly influenced the scar surgical treatment efficacy.

CONCLUSION

With the development of economy in China, more scar patients especially younger and children visit doctors predominantely from the rural areas. Usually, they get their scars in the exposed area of their bodies (head and face) which seriously affect the patient's appearance and function. Factors influencing the scar surgical treatment efficacy has important clinical significance of prevention and treatment.

The inhibitory role of miR-214 in cervical cancer cells through directly targeting mitochondrial transcription factor A (TFAM)

Mitochondrial transcription factor A (TFAM) is a high-mobility group (HMG) protein and acts as a key regulator in mitochondrial DNA (mtDNA) replication, transcription, and inheritance. Accumulating evidence has demonstrated that TFAM plays an important role in tumorigenesis; however, the regulatory mechanism of TFAM in cervical cancer has not been revealed. In the current study, the au- thors found that with malignancy of cervical cancer, the protein expression of TFAM was gradually increased, while the expression of miRNA-214 was gradually downregulated. They further identified that TFAM is a target of miR-214. Forced overexpression of miRNA-214 significantly suppressed cell proliferation, cell cycle progression, colony-formation, and migration of cervical cancer Hela and Caski cells; however, upregulation of TFAM notably promoted cell proliferation, cell cycle progression, colony-formation, and migration of Hela and Caski cells. The authors further showed that miR-214 enhanced the susceptibility of Hela and Caski cells to the chemotherapy drug cisplatin. In conclusion, the current study provides a new sight for the regulatory pattern of miRNA-214 and TFAM in cervical cancer in vitro, indicating that miRNA-214 and MTFA may become important candidates for developing promising therapeutic strategies for the treatment of cervical cancer.

Genetic association between p53 codon 72 polymorphism and risk of cutaneous squamous cell carcinoma

This study was designed to obtain a conclusive result about the relevance of p53 codon 72 polymorphism to the risk of cutaneous squamous cell carcinoma (SCC). We performed an updated meta-analysis of 3,792 subjects (1,349 cancer cases and 2,443 controls) to summarize the data available for p53 codon 72 polymorphism and SCC risk. The association was estimated by odds ratios (ORs) with 95% confidence intervals (CIs). The meta-analysis showed no statistical significance for SCC risk associated with any of the genetic models of p53 codon 72 polymorphism. The analyses by ethnic subgroup also failed to produce significant associations. This study suggests that p53 codon 72 polymorphism does not appear to represent a significant susceptibility factor for SCC in Caucasians.

Neuroprotective effects of LBP on brain ischemic reperfusion neurodegeneration

AIM

The present study was conducted to investigate whether LBP had a protective effect on cerebral ischemic reperfusion injury and to determine the possible mechanisms.

MATERIALS AND METHODS

Male Kunming (KM) mice were used to make the model cerebral artery occlusion/reperfusion (MCAO/R). The behavioral test was used to measure neurological deficit scores for evaluation of ischemic reperfusion damage of brain. The change of electroencephalograph (EEG) was monitored by Model SMUP-E Bio-electric Signals Processing System. The infarction area of brain was assessed in brain slices with 2% solution of 2,3,5-triphenyl tetrazolium chloride (TTC). Spectrophotometric assay was used to determine the activities of superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), catalase (CAT) and lactate dehydrogenase (LDH), contents of malondialdehyde (MDA) and adenosine triphosphate (ATP) of the brain.

RESULTS

The results showed that LBP at doses of 20 and 40 mg/kg markedly decreased the neurological deficit scores and the infarction area in MCAO/R mice. At the same time, LBP significantly decreased MDA content, and increased SOD, GSH-Px, CAT, LDH activities in ischemic reperfusion brain.

CONCLUSIONS

These suggest that LBP might act as a potential neuroprotective agent against the cerebral reperfusion-induced injury in the brain through reducing lipid peroxides, scavenging free radicals, and improving the energy metabolism.

Alterations in metabolic pathways and networks in Alzheimer's disease

The pathogenic mechanisms of Alzheimer's disease (AD) remain largely unknown and clinical trials have not demonstrated significant benefit. Biochemical characterization of AD and its prodromal phase may provide new diagnostic and therapeutic insights. We used targeted metabolomics platform to profile cerebrospinal fluid (CSF) from AD (n=40), mild cognitive impairment (MCI, n=36) and control (n=38) subjects; univariate and multivariate analyses to define between-group differences; and partial least square-discriminant analysis models to classify diagnostic groups using CSF metabolomic profiles. A partial correlation network was built to link metabolic markers, protein markers and disease severity. AD subjects had elevated methionine (MET), 5-hydroxyindoleacetic acid (5-HIAA), vanillylmandelic acid, xanthosine and glutathione versus controls. MCI subjects had elevated 5-HIAA, MET, hypoxanthine and other metabolites versus controls. Metabolite ratios revealed changes within tryptophan, MET and purine pathways. Initial pathway analyses identified steps in several pathways that appear altered in AD and MCI. A partial correlation network showed total tau most directly related to norepinephrine and purine pathways; amyloid-β (Ab42) was related directly to an unidentified metabolite and indirectly to 5-HIAA and MET. These findings indicate that MCI and AD are associated with an overlapping pattern of perturbations in tryptophan, tyrosine, MET and purine pathways, and suggest that profound biochemical alterations are linked to abnormal Ab42 and tau metabolism. Metabolomics provides powerful tools to map interlinked biochemical pathway perturbations and study AD as a disease of network failure.