[Effect of intestinal nitrate on growth of Klebsiella pneumoniae and its regulatory mechanism]

OBJECTIVE

To explore the effect of intestinal nitrates on the growth of Klebsiella pneumoniae and its regulatory mechanisms.

METHODS

K. pneumoniae strains with nitrate reductase narG and narZ single or double gene knockout or with NarXL gene knockout were constructed and observed for both aerobic and anaerobic growth in the presence of KNO3 using an automated bacterial growth analyzer and a spectrophotometer, respectively. The mRNA expressions of narG and narZ in K. pneumoniae in anaerobic cultures in the presence of KNO3 and the effect of the binary regulatory system NarXL on their expresisons were detected using qRT-PCR. Electrophoretic mobility shift assays (EMSA) and MST analysis were performed to explore the specific regulatory mechanisms of NarXL in sensing and utilizing nitrates. Competitive experiments were conducted to examine anaerobic growth advantages of narG and narZ gene knockout strains of K. pneumoniae in the presence of KNO3.

RESULTS

The presence of KNO3 in anaerobic conditions, but not in aerobic conditions, promoted bacterial growth more effectively in the wild-type K. pneumoniae strain than in the narXL gene knockout strain. In anaerobic conditions, the narXL gene knockout strain showed significantly lowered mRNA expressions of narG and narZ (P < 0.0001). EMSA and MST experiments demonstrated that the NarXL regulator could directly bind to narG and narZ promoter regions. The wild-type K. pneumoniae strain in anaerobic cultures showed significantly increased expressions of narG and narZ mRNAs in the presence of KNO3 (P < 0.01), and narG gene knockout resulted in significantly attenuated anaerobic growth and competitive growth abilities of K. pneumoniae in the presence of KNO3 (P < 0.01).

CONCLUSION

The binary regulatory system NarXL of K. pneumoniae can sense changes in intestinal nitrate concentration and directly regulate the expression of nitrate reductase genes narG and narZ to promote bacterial growth.

Molecular characterization of STEAP3 in lung squamous cell carcinoma: Regulating EGFR to affect cell proliferation and ferroptosis

Six-transmembrane epithelial antigen of the prostate 3 (STEAP3) has been reported to play a regulatory role in various types of cancers. However, its involvement in lung squamous cell carcinoma (LUSC) remains understudied. Here, we aimed to explore the biological functions and underlying mechanisms of STEAP3 in LUSC. Intersection genes associated with LUSC and ferroptosis were analyzed using the Venn method, STRING, GEPIA and UALCAN databases. The expression of STEAP3 was detected by qPCR and western blotting assay. Cell proliferation and viability were determined using the cell counting kit-8 assay and EDU staining. Oxidative stress and lipid peroxidation were measured by corresponding kits and DCFH-DA staining. Ferroptosis was evaluated by Phen Green SK and Western blot assay. The correlation between STEAP3 and EGFR was predicted by the TIMER and starBase database. Co-immunoprecipitation was conducted to verify the binding of STEAP3 and EGFR. The data demonstrated a significant upregulation of STEAP3 expression in LUSC cell lines. Silencing of STEAP3 suppressed H2170 cell viability and proliferation while promoting oxidative stress and lipid peroxidation through increased levels of MDA and ROS, as well as inhibited SOD activity. In addition, knockdown of STEAP3 induced ferroptosis through the regulation of ferroptosis-related proteins. Moreover, the binding between STEAP3 and EGFR was predicted and confirmed in LUSC. EGFR overexpression reversed the effects of STEAP3 silencing on H2170 cell viability, proliferation, oxidative stress, and ferroptosis. To summarize, the inhibition of STEAP3/EGFR may serve as a promising therapeutic target for LUSC treatment, as it can suppress LUSC proliferation and promote lipid peroxidation and ferroptosis.

Susceptibility of cervical cancer to dihydroartemisinin-induced ferritinophagy-dependent ferroptosis

The clinical therapeutics of cervical cancer is limited due to the drug resistance and metastasis of tumor. As a novel target for antitumor therapy, ferroptosis is deemed to be more susceptible for those cancer cells with resistance to apoptosis and chemotherapy. Dihydroartemisinin (DHA), the primary active metabolites of artemisinin and its derivatives, has exhibited a variety of anticancer properties with low toxicity. However, the role of DHA and ferroptosis in cervical cancer remained unclear. Here, we showed that DHA could time-dependently and dose-dependently inhibit the proliferation of cervical cancer cells, which could be alleviated by the inhibitors of ferroptosis rather than apoptosis. Further investigation confirmed that DHA treatment initiated ferroptosis, as evidenced by the accumulation of reactive oxygen species (ROS), malondialdehyde (MDA) and liquid peroxidation (LPO) levels and simultaneously depletion of glutathione peroxidase 4 (GPX4) and glutathione (GSH). Moreover, nuclear receptor coactivator 4 (NCOA4)-mediated ferritinophagy was also induced by DHA leading to subsequent increases of intracellular labile iron pool (LIP), exacerbated the Fenton reaction resulting in excessive ROS production, and enhanced cervical cancer ferroptosis. Among them, we unexpectedly found that heme oxygenase-1 (HO-1) played an antioxidant role in DHA-induced cell death. In addition, the results of synergy analysis showed that the combination of DHA and doxorubicin (DOX) emerged a highly synergistic lethal effect for cervical cancer cells, which was related also to ferroptosis. Overall, our data revealed the molecular mechanisms that DHA triggered ferritinophagy-dependent ferroptosis and sensitized to DOX in cervical cancer, which may provide novel avenues for future therapy development.

The Roles of Iron and Ferroptosis in Human Chronic Diseases

Ferroptosis, an iron-dependent novel type of cell death, has been characterized as an excessive accumulation of lipid peroxides and reactive oxygen species. A growing number of studies demonstrate that ferroptosis not only plays an important role in the pathogenesis and progression of chronic diseases, but also functions differently in different diseases. As a double-edged sword, activation of ferroptosis could potently inhibit tumor growth and increase sensitivity to chemotherapy and immunotherapy in various cancer settings. Therefore, the development of more efficacious ferroptosis agonists or inhibitors remains the mainstay of ferroptosis-targeting strategy for cancer therapeutics or cardiovascular and cerebrovascular diseases and neurodegenerative diseases therapeutics.

Downregulation of TNFAIP1 alleviates OGD/R‑induced neuronal damage by suppressing Nrf2/GPX4‑mediated ferroptosis

TNFα-induced protein 1 (TNFAIP1) serve a role in neurovascular disease. However, the potential role and molecular mechanism of TNFAIP1 in cerebral ischemia-reperfusion (I/R) remains elusive. In the present study, reverse transcription-quantitative PCR and western blotting were used to assess TNFAIP1 mRNA and protein expression levels in PC12 cells. Furthermore, using Cell Counting Kit-8, flow cytometry and western blotting, cell viability and apoptosis were evaluated. Oxidative stress was evaluated using DCFH-DA staining and ELISA was used for assessment of inflammatory factors. Expression of components in the nuclear factor erythroid 2-related factor 2 (Nrf2) signaling pathway and ferroptosis were assessed using western blotting analysis and an iron assay kit. TNFAIP1 expression was significantly upregulated in oxygen glucose deprivation and reperfusion (OGD/R)-injured PC12 cells. However, knocking down TNFAIP1 expression restored PC12 cell viability and decreased apoptosis following OGD/R-challenge. Furthermore, TNFAIP1 silencing significantly suppressed OGD/R-induced oxidative stress and inflammatory damage in PC12 cells. TNFAIP1 knockdown inhibited ferroptosis via activation of the Nrf2 signaling pathway in OGD/R-injured PC12 cells. Erastin treatment reversed the beneficial effects of TNFAIP1 knockdown on PC12 cell viability, apoptosis alleviation, oxidative stress and inflammation following OGD/R treatment. These results suggested that TNFAIP1 knockdown could alleviate OGD/R-induced neuronal cell damage by suppressing Nrf2-mediated ferroptosis, which might lay the foundation for the investigation of targeted-therapy for cerebral I/R injury in clinic.

Depinning phase transition of antiferromagnetic skyrmions with quenched disorder

Antiferromagnetic skyrmions are considered to be promising information carriers due to their attractive properties. Therefore, the pinning phenomenon of antiferromagnetic skyrmions is of great significance. With the Landau-Lifshitz-Gilbert equation, we simulate the nonstationary dynamic behaviors of skyrmions driven by currents in a chiral antiferromagnetic thin film with quenched disorder. Based on the dynamic scaling forms, the critical current and static and dynamic critical exponents of the depinning phase transition are accurately determined. A theoretical analysis using Thiele's approach is presented in comparison with the numerical simulation. Unlike the ferromagnetic skyrmions, the critical current of the antiferromagnetic skyrmions is very sensitive to a small nonadiabatic coefficient. This is important for manipulating antiferromagnetic skyrmions and designing novel information processing devices.

Canagliflozin mitigates ferroptosis and improves myocardial oxidative stress in mice with diabetic cardiomyopathy

Canagliflozin (Cana), an anti-diabetes drug belongs to sodium-glucose cotransporter 2 inhibitor, is gaining interest because of its extra cardiovascular benefits. Ferroptosis is a new mode of cell death, which can promote the occurrence of diabetic cardiomyopathy (DCM). Whether Cana can alleviate DCM by inhibiting ferroptosis is the focus of this study. Here, we induced DCM models in diabetic C57BL6 mice and treated with Cana. Meanwhile, in order to exclude its hypoglycemic effect, the high glucose model in H9C2 cells were established. In the in vivo study, we observed that Cana could effectively alleviate the damage of cardiac function in DCM mice, including the increasing of lactate dehydrogenase (LDH) and cardiac troponin I (cTnI), the alleviating of myocardial fiber breakage, inflammation, collagen fiber deposition and mitochondrial structural disorder. We evaluated reactive oxygen species (ROS) levels by DCFH-DA and BODIPY 581/591 C11, in vitro Cana reduced ROS and lipid ROS in H9C2 cells induced by high glucose. Meanwhile, JC-1 fluorochrome assay showed that the decreased mitochondrial membrane potential (MMP) was increased by Cana. Furthermore, the inhibitory effects of Cana on myocardial oxidative stress and ferroptosis were verified in vivo and in vitro by protein carbonyl (PCO), malondialdehyde (MDA), superoxide dismutase (SOD), catalase (CAT), glutathione (GSH). As a key inducer of ferroptosis, the deposition of total iron and Fe²⁺ can be inhibited by Cana both in vivo and in vitro. In addition, western blot results indicated that the expression of ferritin heavy-chain (FTN-H) was down-regulated, and cystine-glutamate antiporter (xCT) was up-regulated by Cana in DCM mice and cells, suggesting that Cana inhibit ferroptosis by balancing cardiac iron homeostasis and promoting the system Xc^-/GSH/GPX4 axis in DCM. These findings underscore the fact that ferroptosis plays an important role in the development and progression of DCM and targeting ferroptosis may be a novel strategy for prevention and treatment. In conclusion, Cana may exert some of its cardiovascular benefits by attenuating ferroptosis.

Fizeau drag in graphene plasmonics

Dragging of light by moving media was predicted by Fresnel¹ and verified by Fizeau's celebrated experiments² with flowing water. This momentous discovery is among the experimental cornerstones of Einstein's special relativity theory and is well understood^3,4 in the context of relativistic kinematics. By contrast, experiments on dragging photons by an electron flow in solids are riddled with inconsistencies and have so far eluded agreement with the theory^5-7. Here we report on the electron flow dragging surface plasmon polaritons^8,9 (SPPs): hybrid quasiparticles of infrared photons and electrons in graphene. The drag is visualized directly through infrared nano-imaging of propagating plasmonic waves in the presence of a high-density current. The polaritons in graphene shorten their wavelength when propagating against the drifting carriers. Unlike the Fizeau effect for light, the SPP drag by electrical currents defies explanation by simple kinematics and is linked to the nonlinear electrodynamics of Dirac electrons in graphene. The observed plasmonic Fizeau drag enables breaking of time-reversal symmetry and reciprocity¹⁰ at infrared frequencies without resorting to magnetic fields^11,12 or chiral optical pumping^13,14. The Fizeau drag also provides a tool with which to study interactions and nonequilibrium effects in electron liquids.

Universality classes of the domain-wall creep motion driven by spin-transfer torques

With the stochastic Landau-Lifshitz-Gilbert equation, we numerically simulate the creep motion of a magnetic domain wall driven by the adiabatic and nonadiabatic spin-transfer torques induced by the electric current. The creep exponent μ and the roughness exponent ζ are accurately determined from the scaling behaviors. The creep motions driven by the adiabatic and nonadiabatic spin-transfer torques belong to different universality classes. The scaling relation between μ and ζ based on certain simplified assumptions is valid for the nonadiabatic spin-transfer torque, while invalid for the adiabatic one. Our results are compatible with the experimental ones, but go beyond the existing theoretical prediction. Our investigation reveals that the disorder-induced pinning effect on the domain-wall rotation alters the universality class of the creep motion.

A Type VI Secretion System Facilitates Fitness, Homeostasis, and Competitive Advantages for Environmental Adaptability and Efficient Nicotine Biodegradation

Gram-negative bacteria employ secretion systems to translocate proteinaceous effectors from the cytoplasm to the extracellular milieu, thus interacting with the surrounding environment or microniche. It is known that bacteria can benefit from the type VI secretion system (T6SS) by transporting ions to combat reactive oxygen species (ROS). Here, we report that T6SS activities conferred tolerance to nicotine-induced oxidative stress in Pseudomonas sp. strain JY-Q, a highly active nicotine degradation strain isolated from tobacco waste extract. AA098_13375 was identified to encode a dual-functional effector with antimicrobial and anti-ROS activities. Wild-type strain JY-Q grew better than the AA098_13375 deletion mutant in nicotine-containing medium by antagonizing increased intracellular ROS levels. It was, therefore, tentatively designated TseN (type VI secretion system effector for nicotine tolerance), homologs of which were observed to be broadly ubiquitous in Pseudomonas species. TseN was identified as a Tse6-like bacteriostatic toxin via monitoring intracellular NAD+ TseN presented potential antagonism against ROS to fine tune the heavy traffic of nicotine metabolism in strain JY-Q. It is feasible that the dynamic tuning of NAD+ driven by TseN could satisfy demands from nicotine degradation with less cytotoxicity. In this scenario, T6SS involves a fascinating accommodation cascade that prompts constitutive biotransformation of N-heterocyclic aromatics by improving bacterial robustness/growth. In summary, the T6SS in JY-Q mediated resistance to oxidative stress and promoted bacterial fitness via a contact-independent growth competitive advantage, in addition to the well-studied T6SS-dependent antimicrobial activities.IMPORTANCE Mixtures of various pollutants and the coexistence of numerous species of organisms are usually found in adverse environments. Concerning biodegradation of nitrogen-heterocyclic contaminants, the scientific community has commonly focused on screening functional enzymes that transform pollutants into intermediates of attenuated toxicity or for primary metabolism. Here, we identified dual roles of the T6SS effector TseN in Pseudomonas sp. strain JY-Q, which is capable of degrading nicotine. The T6SS in strain JY-Q is able to deliver TseN to kill competitors and provide a growth advantage by a contact-independent pattern. TseN could monitor the intracellular NAD+ level by its hydrolase activity, causing cytotoxicity in competitive rivals but metabolic homeostasis on JY-Q. Moreover, JY-Q could be protected from TseN toxicity by the immunity protein TsiN. In conclusion, we found that TseN with cytotoxicity to bacterial competitors facilitated the nicotine tolerance of JY-Q. We therefore reveal a working model between T6SS and nicotine metabolism. This finding indicates that multiple diversified weapons have been evolved by bacteria for their growth and robustness.

Peak Width of Skeletonized Mean Diffusivity as Neuroimaging Biomarker in Cerebral Amyloid Angiopathy

BACKGROUND AND PURPOSE

Whole-brain network connectivity has been shown to be a useful biomarker of cerebral amyloid angiopathy and related cognitive impairment. We evaluated an automated DTI-based method, peak width of skeletonized mean diffusivity, in cerebral amyloid angiopathy, together with its association with conventional MRI markers and cognitive functions.

MATERIALS AND METHODS

We included 24 subjects (mean age, 74.7 [SD, 6.0] years) with probable cerebral amyloid angiopathy and mild cognitive impairment and 62 patients with MCI not attributable to cerebral amyloid angiopathy (non-cerebral amyloid angiopathy-mild cognitive impairment). We compared peak width of skeletonized mean diffusivity between subjects with cerebral amyloid angiopathy-mild cognitive impairment and non-cerebral amyloid angiopathy-mild cognitive impairment and explored its associations with cognitive functions and conventional markers of cerebral small-vessel disease, using linear regression models.

RESULTS

Subjects with Cerebral amyloid angiopathy-mild cognitive impairment showed increased peak width of skeletonized mean diffusivity in comparison to those with non-cerebral amyloid angiopathy-mild cognitive impairment (P < .001). Peak width of skeletonized mean diffusivity values were correlated with the volume of white matter hyperintensities in both groups. Higher peak width of skeletonized mean diffusivity was associated with worse performance in processing speed among patients with cerebral amyloid angiopathy, after adjusting for other MRI markers of cerebral small vessel disease. The peak width of skeletonized mean diffusivity did not correlate with cognitive functions among those with non-cerebral amyloid angiopathy-mild cognitive impairment.

CONCLUSIONS

Peak width of skeletonized mean diffusivity is altered in cerebral amyloid angiopathy and is associated with performance in processing speed. This DTI-based method may reflect the degree of white matter structural disruption in cerebral amyloid angiopathy and could be a useful biomarker for cognition in this population.

Clinical utility of expanded non-invasive prenatal screening and chromosomal microarray analysis in high-risk pregnancy

OBJECTIVE

To evaluate the utility of expanded non-invasive prenatal screening (NIPS), compared with chromosomal microarray analysis (CMA), for the detection of chromosomal abnormalities in high-risk pregnancies.

METHODS

This was a multicenter retrospective study of singleton pregnancies at high risk for chromosomal abnormality. Patients who underwent expanded NIPS and CMA sequentially during pregnancy from 2015 to 2019 were included in the analysis. Pregnancies with a positive result for sex chromosome aneuploidy were excluded as the full details could not be retrieved. The utility of expanded NIPS and CMA for detection of chromosomal abnormalities in this cohort was compared by assessing the concordance between the results.

RESULTS

Of the 774 included high-risk pregnancies, 550 (71.1%) had a positive NIPS result, while a positive CMA result was detected in 308 (39.8%) cases. The rate of full or partial concordance between NIPS and CMA was 82.2%, 59.6% and 25.0% for trisomies 21, 18 and 13, respectively. For rare aneuploidies and segmental imbalances, NIPS and CMA results were fully or partially concordant in 7.5% and 33.3% of cases, respectively. Copy-number variants < 5 Mb were detected more often by CMA, with an incidence of 7.9% (61/774) compared with 3.1% (24/774) by NIPS. A genetic aberration was detected by CMA in 1 in 17 (5.8%) high-risk pregnancies that had a negative or non-reportable NIPS result.

CONCLUSION

CMA allows for comprehensive detection of genome-wide chromosomal abnormalities in high-risk pregnancies. CMA should be offered instead of expanded NIPS for high-risk pregnancies. Copyright © 2020 ISUOG. Published by John Wiley & Sons Ltd.

MicroRNA-1286 inhibits osteogenic differentiation of mesenchymal stem cells to promote the progression of osteoporosis via regulating FZD4 expression

OBJECTIVE

The aim of this study was to investigate whether microRNA-1286 could inhibit the osteogenic differentiation of human marrow mesenchymal stem cells (hMSCs) by regulating FZD4 expression and promoting the progression of osteoporosis.

PATIENTS AND METHODS

Quantitative Real Time-Polymerase Chain Reaction (qRT-PCR) was used to detect the expression of microRNA-1286 in the serum of patients with osteoporosis. Meanwhile, microRNA-1286 expression in different stages of osteogenic differentiation of hMSCs was measured by qRT-PCR as well. After overexpression of microRNA-1286 and FZD4 in hMSCs, the mRNA expression levels of microRNA-1286, alkaline phosphatase (ALP), RUNX2 and osteocalcin (OCN) were detected by qRT-PCR. The protein expression levels of RUNX2 and OCN were detected by Western blot. Meanwhile, alkaline phosphatase (ALP) activity and expression in cells were examined using ALP assay kit and ALP staining method, respectively. Cell mineralized nodules were detected through the alizarin red staining test. Bioinformatics method was used to predict the binding site of microRNA-1286 to FZD4. Subsequent luciferase reporter gene assay was performed to verify whether microRNA-1286 could combine with FZD4. After overexpression or knockdown of microRNA-1286, the mRNA and protein expressions of FZD4 were analyzed using qRT-PCR and Western blot assay, respectively. After the simultaneous overexpression of microRNA-1286 and FZD4 in hMSCs, the mRNA expression levels of ALP, RUNX2 and OCN, ALP activity and content, and cell mineralization ability were successively examined.

RESULTS

The expression of microRNA-1286 in the serum of patients with osteoporosis was significantly higher than that of the normal population. Meanwhile, microRNA-1286 expression decreased with the increase of osteogenic differentiation days of hAMSCs. After the overexpression of microRNA-1286, ALP, RUNX2, and OCN levels, ALP activity, RUNX2, and OCN protein levels, as well as mineralized nodule formation were significantly reduced. However, results were reversed when FZD4 was simultaneously up-regulated. Luciferase reporter gene assay results verified that microRNA-1286 could bind to FZD4. After the overexpression of microRNA-1286, the mRNA and protein expressions of FZD4 were found significantly down-regulated. However, results were reversed after knocking down microRNA-1286. Furthermore, the simultaneous overexpression of microRNA-1286 and FZD4 could counteract the inhibitory effect of over-expression of microRNA-1286 on osteogenic differentiation of hMSCs.

CONCLUSIONS

MicroRNA-1286 can regulate FZD4 expression and inhibit osteogenic differentiation of hMSCs, thereby promoting the development of osteoporosis.

Coronavirus disease 2019: A new severe acute respiratory syndrome from Wuhan in China

An outbreak of new severe acute respiratory syndrome coronavirus disease, coronavirus disease 2019 (COVID-19), has emerged during December 2019. The ongoing outbreak in Wuhan City spread rapidly throughout China, where the fatality rate ranged from 2.1 to 4.9%. Due to its high transmissibility, the World Health Organization (WHO) declared a public health emergency of international concern on 30 January 2020. The current outbreak has the potential to become the first pandemic of the new millennium. Most patients who were first diagnosed with COVID-19 worked at or lived in the vicinity of the local Huanan Seafood Wholesale  Market, where live animals were also on sale. The concerted efforts of Chinese scientists led to the independent isolation from patients and identification of a novel coronavirus, SARS coronavirus 2 (SARS-CoV-2), on 6 January 2020; this has been an important step in the development of treatment. The purpose of this article is to overview the history, epidemiology, clinical characteristics, diagnosis, and treatment of COVID 2019 reported in recently published studies. Based on the results of virus genome sequencing and a model of the interaction between host cells and the virus, we propose several possible targets for antiviral drugs, which may provide new ideas for epidemic control and vaccine development. Keywords: 2019 novel coronavirus; pneumonia; SARS-CoV-2; Coronaviridae; COVID-19.

The Application of Non-linear Flow Resistance in Cerebral Artery: Compared with Windkessel Model based on Genetic Algorithm

Continuous blood pressure is measured from various extracranial body sites, with difference in amplitude and phase with intracranial blood pressure. Consequent influences on the accuracy of Windkessel model need further investigation. Between blood pressure and intracranial flow rate, a model with non-linear flow resistance (R-DT) was proposed and compared with the 3-element Windkessel (RCR) model. From the measured blood flow velocity in middle cerebral artery, the blood pressure was estimated by R-DT and RCR models respectively. The parameters in the models were optimized by genetic algorithm. The accuracies of R-DT and RCR models were compared based on their estimation errors to the measured blood pressure. The capacitance element in RCR model indicated limited ability to take the time shift into account. Compared with RCR model, R-DT model had less error (averaged relative error: 5.19% and 2.49% for RCR and RDT models). The non-linear flow resistance was applicable in simulating cerebral arteries.

MiR-93 blocks STAT3 to alleviate hepatic injury after ischemia-reperfusion

OBJECTIVE

Signal transducer and activator of transcription 3 (STAT3) is correlated with ischemia-reperfusion (I-R) injury. The previous studies showed a decreased miR-93 expression after I-R injury of heart or brain organs, but without knowledge in liver tissues. This study aims to investigate effects of MiR-93 on the hepatic injury after ischemia/reperfusion.

MATERIALS AND METHODS

Rat liver I-R model was generated. Liver function indexes including alanine transaminase (ALT) and aspartate aminotransferase (AST) were quantified, and serum tumor necrosis factor α (TNF-α), interleukin-1β (IL-1β), and interleukin-6 (IL-6) levels were quantified. Hepatic tissue apoptosis was measured by transferase-mediated deoxyuridine triphosphate-biotin nick end labeling (TUNEL), and expression of microRNA-93 (miR-93), STAT3, and phosphorylated STAT3 (p-STAT3) were measured. Dual luciferase reporter gene assay confirmed targeted relationship between miR-93 and STAT3. Agomir or miR-93 agomir was injected into the peritoneal cavity of I-R model, followed by ALT and AST assays. Serum levels of TNF-α, IL-1β, and IL-6 were measured, followed by TUNEL assay for comparing STAT3 and p-STAT3 expression.

RESULTS

Comparing to sham group, I-R group rat showed significantly elevated serum ALT, AST, TNF-α, IL-1β, and IL-6 contents, along with significantly elevated hepatic cell apoptosis, plus decreased miR-93 expression, whilst STAT3 and p-STAT3 expression was enhanced. Intraperitoneal injection of miR-93 agomir significantly decreased STAT3 or p-STAT3 expression, and decreased cell apoptotic rate. Serum levels of ALT, AST, TNF-α, IL-1β, and IL-6 were significantly decreased, accompanied by improved liver function.

CONCLUSIONS

Hepatic I-R injury is accompanied by miR-93 down-regulation, plus STAT3 up-regulation. Overexpression of miR-93 significantly depressed STAT3 expression in liver I-R injury, alleviated hepatic injury or apoptosis, decreased inflammatory response, and improved liver function.

Photonic crystal for graphene plasmons

Photonic crystals are commonly implemented in media with periodically varying optical properties. Photonic crystals enable exquisite control of light propagation in integrated optical circuits, and also emulate advanced physical concepts. However, common photonic crystals are unfit for in-operando on/off controls. We overcome this limitation and demonstrate a broadly tunable two-dimensional photonic crystal for surface plasmon polaritons. Our platform consists of a continuous graphene monolayer integrated in a back-gated platform with nano-structured gate insulators. Infrared nano-imaging reveals the formation of a photonic bandgap and strong modulation of the local plasmonic density of states that can be turned on/off or gradually tuned by the applied gate voltage. We also implement an artificial domain wall which supports highly confined one-dimensional plasmonic modes. Our electrostatically-tunable photonic crystals are derived from standard metal oxide semiconductor field effect transistor technology and pave a way for practical on-chip light manipulation.

Traditional photonic crystals consist of periodic media with a pre-defined optical response. Here, the authors combine nanostructured back-gate insulators with a continuous layer of graphene to demonstrate an electrically tunable two-dimensional photonic crystal suitable for controlling the propagation of surface plasmon polaritons.

Photonic crystals for nano-light in moiré graphene superlattices

Graphene is an atomically thin plasmonic medium that supports highly confined plasmon polaritons, or nano-light, with very low loss. Electronic properties of graphene can be drastically altered when it is laid upon another graphene layer, resulting in a moiré superlattice. The relative twist angle between the two layers is a key tuning parameter of the interlayer coupling in thus-obtained twisted bilayer graphene (TBG). We studied the propagation of plasmon polaritons in TBG by infrared nano-imaging. We discovered that the atomic reconstruction occurring at small twist angles transforms the TBG into a natural plasmon photonic crystal for propagating nano-light. This discovery points to a pathway for controlling nano-light by exploiting quantum properties of graphene and other atomically layered van der Waals materials, eliminating the need for arduous top-down nanofabrication.

Mechanisms of endogenous repair failure during intervertebral disc degeneration

Intervertebral disc (IVD) degeneration is frequently associated with Low back pain (LBP), which can severely reduce the quality of human life and cause enormous economic loss. However, there is a lack of long-lasting and effective therapies for IVD degeneration at present. Recently, stem cell based tissue engineering techniques have provided novel and promising treatment for the repair of degenerative IVDs. Numerous studies showed that stem/progenitor cells exist naturally in IVDs and could migrate from their niche to the IVD to maintain the quantity of nucleus pulposus (NP) cells. Unfortunately, these endogenous repair processes cannot prevent IVD degeneration as effectively as expected. Therefore, theoretical basis for regeneration of the NP in situ can be obtained from studying the mechanisms of endogenous repair failure during IVD degeneration. Although there have been few researches to study the mechanism of cell death and migration of stem/progenitor cells in IVD so far, studies demonstrated that the major inducing factors (compression and hypoxia) of IVD degeneration could decrease the number of NP cells by regulating apoptosis, autophagy, and necroptosis, and the particular chemokines and their receptors played a vital role in the migration of mesenchymal stem cells (MSCs). These studies provide a clue for revealing the mechanisms of endogenous repair failure during IVD degeneration. This article reviewed the current research situation and progress of the mechanisms through which IVD stem/progenitor cells failed to repair IVD tissues during IVD degeneration. Such studies provide an innovative research direction for endogenous repair and a new potential treatment strategy for IVD degeneration.

[Gastroesophageal reflux disease is associated with high risk of obstructive sleep apnea syndrome]

Objective: To investigate the relationship between gastroesophageal reflux disease (GERD) and obstructive sleep apnea syndrome(OSAS). Methods: Patients diagnosed as GERD and healthy controls without GERD related symptoms or endoscopic esophagitis were enrolled from October 2017 and December 2017. All subjects completed Berlin Questionaire to assess the risk of OSAS. Univariate and multivariate logistic regression models were applied to identify risk factors of OSAS. Results: A total of 177 subjects (97 GERD, 80 controls) were finally selected. Significantly more patients in GERD group had high risk OSAS than those in controls [36.1%(35/97) vs. 17.5%(14/80), P=0.005]. In GERD group, patients with erosive reflux diseases (ERD) had especially higher proportion of high risk OSAS compared with the non-ERD group and the healthy controls [53.3% (24/45) vs. 20.8% (10/48) and 17.5% (14/80), P=0.001]. On univariate analysis, male, aging and reflux esophagitis were identified as risk factors of OSAS (all P<0.01). On multivariate analysis, male (OR=12.156, 95%CI 1.382-106.905, P=0.024), aging (OR=1.132, 95%CI 1.051-1.220, P=0.001), acid regurgitation with reflux esophagitis (OR=5.157, 95%CI 1.327-20.034, P=0.018) were significant risk factors. Conclusions: More GERD patients are combined with high risk OSAS than controls, especially subjects with reflux esophagitis. Male and aging GERD patients with acid regurgitation and reflux esophagitis need further evaluation on OSAS screening.

Numerical simulations of critical dynamics in anisotropic magnetic films with the stochastic Landau-Lifshitz-Gilbert equation

With the stochastic Landau-Lifshitz-Gilbert (sLLG) equation, critical dynamic behaviors far from equilibrium or stationary around the order-disorder and pinning-depinning phase transitions in anisotropic magnetic films are investigated. From the dynamic relaxation with and without an external field, the Curie temperature and critical exponents of the order-disorder phase transition are accurately determined. For the pinning-depinning phase transition induced by quenched disorder, the nonstationary creep motion of domain wall activated by finite temperatures is simulated, and the thermal rounding exponent is extracted. The results show that the dynamic universality class of the sLLG equation is different from those of the Monte Carlo dynamics and quenched Edwards-Wilkinson equation, and it may lead to alternative understanding of experiments. The dynamic approach shows its great efficiency for the sLLG equation.

The incidence of military training-related injuries in Chinese new recruits: a systematic review and meta-analysis

INTRODUCTION

Training-related injuries are the main reason for disability, long-term rehabilitation, functional impairment and premature discharge from military service. The aim of this study was to identify the incidence of injuries in the training of Chinese new recruits via a systematic review of the literature.

METHOD

A systematic review and meta-analysis was conducted to evaluate the combined incidence of military training-related injuries in Chinese new recruits. The electronic databases of full-text journals were searched, and the Loney criteria were used to assess the quality of eligible articles. Summary estimates were obtained using random-effects models. Subgroup analyses and publication bias tests were performed.

RESULTS

Fifty-five eligible articles representing 109 611 Chinese new recruits met the inclusion criteria, of which 21 253 recruits were clinically diagnosed with military training-related injuries. The combined incidence of military training-related injuries in Chinese new recruits was found to be 21.04%.

CONCLUSIONS

An increased incidence of training injuries was found in more recent years, underscoring the need for further research on the risk factors associated with their causation.

Comparative Genomics Reveals Specific Genetic Architectures in Nicotine Metabolism of Pseudomonas sp. JY-Q

Microbial degradation of nicotine is an important process to control nicotine residues in the aqueous environment. In this study, a high active nicotine degradation strain named Pseudomonas sp. JY-Q was isolated from tobacco waste extract (TWE). This strain could completely degrade 5.0 g l⁻¹ nicotine in 24 h under optimal culture conditions, and it showed some tolerance even at higher concentrations (10.0 g l⁻¹) of nicotine. The complete genome of JY-Q was sequenced to understand the mechanism by which JY-Q could degrade nicotine and tolerate such high nicotine concentrations. Comparative genomic analysis indicated that JY-Q degrades nicotine through putative novel mechanisms. Two candidate gene cluster duplications located separately at distant loci were predicted to be responsible for nicotine degradation. These two nicotine (Nic) degradation-related loci (AA098_21325—AA098_21340, AA098_03885—AA098_03900) exhibit nearly completely consistent gene organization and component synteny. The nicotinic acid (NA) degradation gene cluster (AA098_17770–AA098_17790) and Nic-like clusters were both predicted to be flanked by mobile genetic elements (MGE). Furthermore, we analyzed the regions of genomic plasticity (RGP) in the JY-Q strain and found a dynamic genome carrying a type VI secretion system (T6SS) that promotes nicotine metabolism and tolerance based on transcriptomics and used in silico methods to identify the T6SS effector protein. Thus, a novel nicotine degradation mechanism was elucidated for Pseudomonas sp. JY-Q, suggesting its potential application in the bioremediation of nicotine-contaminated environments, such as TWEs.

Open Right Hemicolectomy Is a Safe and Suitable Procedure for Surgical Training: A Comparative Study With 133 Patients

BACKGROUND AND AIMS

A right hemicolectomy is a technically demanding procedure and the quality of the operation influences the short- and long-term outcomes. An increasing number of certified centers employ surgeons who are specialized in this procedure. Residency training is obligatory, but trainee surgeons often cannot perform technically demanding procedures because of economical and certification requirements imposed on the center. This study was performed to evaluate the suitability of right hemicolectomy as a training procedure.

MATERIAL AND METHODS

Between 2009 and 2013, 133 patients received a right hemicolectomy during cancer treatment. Patient data were analyzed in two cohorts: cohort 1 contained 90 patients who were operated by a resident under supervision, and cohort 2 included 43 patients who were operated by a specialized senior surgeon. Outcome and safety were evaluated by mortality rate, anastomotic leakage, complication rate, and operation time. The resection status and the number of resected lymph nodes were surrogate parameters for oncological quality. Gender, age, American Society of Anesthesiologists classification, body mass index, and general risk factors were compared in both cohorts.

RESULTS

There was no significant difference in the rate of anastomotic leakage between the two groups (p = 0.799). Oncological criteria were met in both cohorts and the oncological quality was similar between groups. Furthermore, there were no significant differences in risk factors, operating time, postoperative complications, and mortality between the groups.

CONCLUSION

Oncological open right hemicolectomy is a safe and suitable training procedure for residency training under standardized conditions.

[Efficacy and safety of tiotropium Respimat in the treatment of chronic obstructive pulmonary disease: systematic review]

Objective: To evaluate the efficacy and safety of tiotropium Respimat in the treatment of chronic obstructive pulmonary disease (COPD) according to the Cochrane systematic evaluation. Methods: The Cochrane Library, PubMed, EMbase, CNKI, VIP and CBM, Wanfang Data were searched(from the foundation date to Jan. 2016) for the randomized controlled trials (RCTs) of tiotropium Respimat in the treatment of patients with COPD. Two reviewers independently retrieved the RCTs according to the inclusion and exclusion criteria, assessed the methodological quality of the included trials.and performed statistical analysis on the data using RevMan 5.3 software. Results: Totally 11 RCTs on efficacy were finally included.The results of the combined analysis showed that FEV(1) was significantly improved in the tiotropium Respimat group than that in the placebo group[MD=0.12, 95%CI(0.10-0.14), P<0.000 01], while FEV(1) was similar between the tiotropium Respimat group and the tiotropium HandiHaler group[5 μg: MD=0.00, 95%CI(-0.04-0.04), P=0.94; 2.5 μg: MD=-0.04, 95%CI(-0.10-0.01), P=0.12; 10 μg: MD=0.02, 95%CI(-0.06-0.09), P=0.66]. FVC was significantly improved in the tiotropium Respimat group than that in the placebo group[MD=0.18, 95%CI(0.09-0.28), P=0.0002], while FVC was similar between the tiotropium Respimat group and the HandiHaler group[2.5 μg: MD=-0.06, 95%CI(-0.16-0.04), P=0.24; 5 μg: MD=-0.00, 95%CI(-0.08-0.08), P=1.00; 10 μg: MD=0.02, 95%CI(-0.14-0.19), P=0.78]. The risk of acute exacerbations was lower in the tiotropium Respimat group (5 μg / kg) than in the placebo group [OR=0.72, 95%CI(0.60-0.86), P=0.000 3]. It was similar in the tiotropium Respimat group (5 μg) and the HandiHaler group[OR=1.01, 95%CI(0.94-1.09), P=0.71]. The SGRQ total score of the tiotropium Respimat group (5 μg) was significantly different from that of the placebo group[MD=-3.6, 95%CI(-3.88--3.32), P<0.000 01]. C(max, ss) and AUC(0-6 h, ss) were also similar between the tiotropium Respimat group and the HandiHaler group[MD=0.2, 95%CI(-5.1-5.5), P=0.94]; MD=-1.01, 95%CI(-11.78-9.77), P=0.85]. Nine RCTs were included in the evaluation of the incident rates of adverse drug reactions(ADR). There was no significant difference between the tiotropium Respimat group HandiHaler group and the placebo group[RR=0.95, 95%CI(0.89-1.00), P=0.05], [OR=1.07, 95%CI(1.00-1.16), P=0.06]. Conclusions: The efficacy and safety of tiotropium Respimat was similar to tiotropium HandiHaler in the treatment of COPD. They can effectively improve the pulmonary function and clinical symptoms of patients. But the long-term efficacy and safety of tiotropium Respimat still need to be confirmed by higher quality and larger RCTs with long-term follow-up.

Phylogenetic relationships and divergence dates of softshell turtles (Testudines: Trionychidae) inferred from complete mitochondrial genomes

The softshell turtles (Trionychidae) are one of the most widely distributed reptile groups in the world, and fossils have been found on all continents except Antarctica. The phylogenetic relationships among members of this group have been previously studied; however, disagreements regarding its taxonomy, its phylogeography and divergence times are still poorly understood as well. Here, we present a comprehensive mitogenomic study of softshell turtles. We sequenced the complete mitochondrial genomes of 10 softshell turtles, in addition to the GenBank sequence of Dogania subplana, Lissemys punctata, Trionyx triunguis, which cover all extant genera within Trionychidae except for Cyclanorbis and Cycloderma. These data were combined with other mitogenomes of turtles for phylogenetic analyses. Divergence time calibration and ancestral reconstruction were calculated using BEAST and RASP software, respectively. Our phylogenetic analyses indicate that Trionychidae is the sister taxon of Carettochelyidae, and support the monophyly of Trionychinae and Cyclanorbinae, which is consistent with morphological data and molecular analysis. Our phylogenetic analyses have established a sister taxon relationship between the Asian Rafetus and the Asian Palea + Pelodiscus + Dogania + Nilssonia + Amyda, whereas a previous study grouped the Asian Rafetus with the American Apalone. The results of divergence time estimates and area ancestral reconstruction show that extant Trionychidae originated in Asia at around 108 million years ago (MA), and radiations mainly occurred during two warm periods, namely Late Cretaceous-Early Eocene and Oligocene. By combining the estimated divergence time and the reconstructed ancestral area of softshell turtles, we determined that the dispersal of softshell turtles out of Asia may have taken three routes. Furthermore, the times of dispersal seem to be in agreement with the time of the India-Asia collision and opening of the Bering Strait, which provide evidence for the accuracy of our estimation of divergence time. Overall, the mitogenomes of this group were used to explore the origin and dispersal route of Trionychidae and have provided new insights on the evolution of this group.

Pharmacokinetics of valnemulin after intravenous, intramuscular, and oral administration in layer chickens

The pharmacokinetic characteristics of valnemulin in layer chickens were studied after single intravenous, intramuscular, and oral administration at a dose of 15 mg/kg body weight. Plasma samples at certain time points were collected and the drug concentrations in them by ultra high-performance liquid chromatography tandem mass spectrometry (UHPLC-MS). The concentration-time data for each individual were plotted by noncompartmental analysis for the whole three routes. Following intravenous administration, the plasma concentration showed tiny fluctuation. The elimination half-life (T1/2λz), total body clearance (Cl), and area under the plasma concentration-time curve (AUC) were 1.85 ± 0.43 h, 2.2 ± 0.9 L/h, and 7.52 ± 2.46 μg·h/mL, respectively. Following intramuscular administration, the peak concentration (C_max , 1.40 ± 0.43 μg/mL) was achieved at the time of 0.34 h. A multiple-peak phenomenon existed after oral administration, and the first peak and secondary peak were at 10 min and during 2-4 h, respectively, while the tertiary peak appeared during 5-15 h. The bioavailability (F %) for intramuscular and oral administration was 68.60% and 52.64%, respectively. In present study, the detailed pharmacokinetic profiles showed that this drug is widely distributed and rapidly eliminated, however has a low bioavailability, indicating that valnemulin is likely to be a favorable choice in the clinical practice.

The DSM5/RDoC debate on the future of mental health research: implication for studies on human stress and presentation of the signature bank

In 2008, the National Institute of Mental Health (NIMH) announced that in the next few decades, it will be essential to study the various biological, psychological and social "signatures" of mental disorders. Along with this new "signature" approach to mental health disorders, modifications of DSM were introduced. One major modification consisted of incorporating a dimensional approach to mental disorders, which involved analyzing, using a transnosological approach, various factors that are commonly observed across different types of mental disorders. Although this new methodology led to interesting discussions of the DSM5 working groups, it has not been incorporated in the last version of the DSM5. Consequently, the NIMH launched the "Research Domain Criteria" (RDoC) framework in order to provide new ways of classifying mental illnesses based on dimensions of observable behavioral and neurobiological measures. The NIMH emphasizes that it is important to consider the benefits of dimensional measures from the perspective of psychopathology and environmental influences, and it is also important to build these dimensions on neurobiological data. The goal of this paper is to present the perspectives of DSM5 and RDoC to the science of mental health disorders and the impact of this debate on the future of human stress research. The second goal is to present the "Signature Bank" developed by the Institut Universitaire en Santé Mentale de Montréal (IUSMM) that has been developed in line with a dimensional and transnosological approach to mental illness.