Novel Clinical mNGS-Based Machine Learning Model for Rapid Antimicrobial Susceptibility Testing of Acinetobacter baumannii.

Multidrug-resistant (MDR) bacteria are important public health problems. Antibiotic susceptibility testing (AST) currently uses time-consuming culture-based procedures, which cause treatment delays and increased mortality. We developed a machine learning model using Acinetobacter baumannii as an example to explore a fast AST approach using metagenomic next-generation sequencing (mNGS) data. The key genetic characteristics associated with antimicrobial resistance (AMR) were selected through a least absolute shrinkage and selection operator (LASSO) regression model based on 1,942 A. baumannii genomes. The mNGS-AST prediction model was accordingly established, validated, and optimized using read simulation sequences of clinical isolates. Clinical specimens were collected to evaluate the performance of the model retrospectively and prospectively. We identified 20, 31, 24, and 3 AMR signatures of A. baumannii for imipenem, ceftazidime, cefepime, and ciprofloxacin, respectively. Four mNGS-AST models had a positive predictive value (PPV) greater than 0.97 for 230 retrospective samples, with negative predictive values (NPVs) of 100% (imipenem), 86.67% (ceftazidime), 86.67% (cefepime), and 90.91% (ciprofloxacin). Our method classified antibacterial phenotypes with an accuracy of 97.65% for imipenem, 96.57% for ceftazidime, 97.64% for cefepime, and 98.36% for ciprofloxacin. The average reporting time of mNGS-based AST was 19.1 h, in contrast to the 63.3 h for culture-based AST, thus yielding a significant reduction of 44.3 h. mNGS-AST prediction results coincided 100% with the phenotypic AST results when testing 50 prospective samples. The mNGS-based model could be used as a rapid genotypic AST approach to identify A. baumannii and predict resistance and susceptibility to antibacterials and could be applicable to other pathogens and facilitate rational antimicrobial usage.

Chaetospirolactone reverses the apoptotic resistance towards TRAIL in pancreatic cancer.

The pancreatic cancer is one of the most aggressive tumors. Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) can trigger apoptosis by interaction with death receptors. However, in TRAIL-resistant pancreatic cancer, responsiveness to TRAIL treatment is terribly poor. In current work, we have demonstrated that a natural product chaetospirolactone (CSL) isolated from an endophytic fungus Chaetomium sp. NF00754 can enhance the susceptibility of TRAIL-resistant pancreatic cancer cells to apoptosis. CSL can induce apoptosis in TRAIL-treated pancreatic cancer cells. Furthermore, combined CSL and TRAIL treatment significantly inhibits viability and migration of pancreatic cancer cells. Combinatorial TRAIL and CSL treatment repressed xenograft tumor growth without substantially toxic side effects. CSL can specifically upregulate expression of death receptor 4 (DR4). Further study revealed that CSL represses the activities of an epigenetic regulator enhancer of zeste homolog 2 (EZH2) and consistently reduces histone H3 lysine 27 trimethylation (H3K27me3) to allow DR4 transcription. Taken together, CSL treatment may reverse TRAIL resistance in pancreatic cancer cells via epigenetic regulation of DR4 implying that administration of CSL might represent a putative strategy for pancreatic cancer therapy.

N,O-Bidentate ligand-tunable copper(ii) complexes as a catalyst for Chan-Lam coupling reactions of arylboronic acids with 1H-imidazole derivatives.

An efficient procedure for Chan-Lam coupling reactions of arylboronic acids with 1H-imidazole derivatives using N,O-bidentate ligand-tunable copper(ii) complexes as a catalyst under base-free conditions has been developed. This protocol features mild reaction conditions, high yields and compatibility with different functional groups, providing a direct and facile strategy for the construction of C-N bonds and synthesis of heterocyclic compounds.

Rhodium-catalyzed direct C-H amidation of azobenzenes with sulfonyl azides: a synthetic route to sterically hindered ortho-substituted aromatic azo compounds.

A rhodium(III)-catalyzed direct ortho-amidation of azobenzenes with sulfonyl azides as the amino source is disclosed. This reaction exhibits a broad substrate scope, high functional group tolerance, and regioselectivity, providing a variety of sterically hindered ortho-substituted azobenzene derivatives in good to excellent yield.

Rhodium-catalyzed ortho-cyanation of symmetrical azobenzenes with N-cyano-N-phenyl-p-toluenesulfonamide.

A rhodium-catalyzed ortho-cyanation of symmetrical azobenzenes is described employing N-cyano-N-phenyl-p-toluenesulfonamide as an environmentally friendly cyanide source. The present protocol allows the synthesis of various benzonitrile derivatives in moderate to good yields and tolerates many useful functional groups.

Developing a Scale for Measuring the Fundamental Movement Skills of Preschool Children in China.

Children aged 3-6 years (preschool children hereafter) are in a critical and sensitive period of developing fundamental movement skills (FMS). While appropriate measurement tools can accurately evaluate their FMS development, such a scale is lacking in China. In this study, a suitable scale for measuring the FMS of preschool children in China was developed by combining process- and results-oriented evaluation methods. The subjects of this cross-sectional study included 21 experts and 358 preschool children (188 boys and 170 girls). Based on a literature review, items suitable for measuring the FMS of preschool children in China were selected, and the final measurement scale includes 12 items in three dimensions: physical locomotion skills, object control skills, and physical stability skills. After a battery of tests to assess its suitability, including inter-rater reliability, test/retest reliability, homogeneity, and construct validity, we find that the proposed measurement scale has good reliability, validity, and sensitivity. This scale reflects the development level of the FMS of preschool children in China and can be used to monitor the FMS of this population in the future.

Catalytic enantioselective aryl transfer to aldehydes using chiral 2,2'-bispyrrolidine-based salan ligands.

Chiral C2-symmetric diamines have emerged as versatile auxiliaries or ligands in numerous asymmetric transformations. Chiral 2,2'-bispyrrolidine-based salan ligands were prepared and applied to the asymmetric aryl transfer to aldehydes with arylboronic acids as the source of transferable aryl groups. The corresponding diarylmethanols were obtained in high yields with moderate to good enantioselectivitives of up to 83% ee.

One-step efficient generation of dual-function conditional knockout and geno-tagging alleles in zebrafish.

CRISPR/Cas systems are widely used to knock out genes by inducing indel mutations, which are prone to genetic compensation. Complex genome modifications such as knockin (KI) might bypass compensation, though difficult to practice due to low efficiency. Moreover, no 'two-in-one' KI strategy combining conditional knockout (CKO) with fluorescent gene-labeling or further allele-labeling has been reported. Here, we developed a dual-cassette-donor strategy and achieved one-step and efficient generation of dual-function KI alleles at tbx5a and kctd10 loci in zebrafish via targeted insertion. These alleles display fluorescent gene-tagging and CKO effects before and after Cre induction, respectively. By introducing a second fluorescent reporter, geno-tagging effects were achieved at tbx5a and sox10 loci, exhibiting CKO coupled with fluorescent reporter switch upon Cre induction, enabling tracing of three distinct genotypes. We found that LiCl purification of gRNA is critical for highly efficient KI, and preselection of founders allows the efficient germline recovery of KI events.

Wnt signaling pathway upregulates DNMT1 to trigger NHERF1 promoter hypermethylation in colon cancer.

NHERF1 is downregulated and has been identified as a new marker of colorectal cancer. However, the molecular mechanism of NHERF1 downregulation in colon cancer is not well understood. In the present study, we demonstrated that the NHERF1 mRNA level was downregulated and correlated with outcomes in colon cancer patients. NHERF1 expression was associated with EMT phenotype. High levels of promoter methylation of NHERF1 in colon cancer were observed. NHERF1 expression was restored by demethylation treatment. In addition, a negative correlation between methylation and mRNA expression of NHERF1 was observed in the TCGA dataset. Moreover, DNMT1 inhibited NHERF1 expression in vivo. DNMT1 expression was found to be negatively correlated with NHERF1 and NHERF1 expression was also restored by a DNMT1 inhibitor. DNMT1 and NHERF1 were regulated by the Wnt signaling pathway. In addition, among DNMT1 high expression patients, the Wnt signaling pathway was negatively correlated with NHERF1 expression. In contrast, among DNMT1 low expression patients, the Wnt signaling pathway was not correlated with NHERF1 expression. In conclusion, Wnt signaling increases DNMT1 expression. DNMT1 contributes to promoter hypermethylation and epigenetic NHERF1 silencing in colon cancer. In addition, we provide novel insight into the mechanisms underlying the regulation of NHERF1 expression and occurrence/progression of colon cancer.

[Naoluoxintong reduces protein expression of TLR4, TRAF6 and TNF-α in frontal and parietal cortex of rats with focal cerebral ischemia reperfusion].

Objective To investigate the effect of Naoluoxintong on the protein expression of Toll like receptor 4 (TLR4), tumor necrosis factor receptor associated factor-6 (TRAF6) and tumor necrosis factor-α (TNF-α) in the frontal and parietal cortex of the rats with middle cerebral artery occlusion and reperfusion (MCAO/R). Methods The modified rat model of MCAO/R was established by suture method. SD rats were randomly divided into four groups: a sham control group, a model group, a Tongxinluo group, and a Naoluoxintong group, with 30 rats in each group. Western blotting was used to detect the expression of TLR4 and TRAF6 in the ischemic lateral frontal cortex, and the expression of TNF-α was measured by immunohistochemistry. Results Compared with the sham control group, the model group had significantly higher expression of TLR4 and TRAF6 on the 3rd, 7th and 14th days, which were reduced by Naoluoxintong and Tongxinluo treatments. Interestingly, the expression of TLR4 on the 3rd, 7th and 14th days were lower in the Naoluoxintong group as compared with those in the Tongxinluo group. Immunohistochemistry showed that TNF-α expression was also enhanced in the model group on the 3rd and 7th days, which were reduced by Naoluoxintong and Tongxinluo treatments. However, TNF-α expression at the different time points was no significantly difference between the Naoluoxintong and Tongxinluo groups. Conclusion Naoluoxintong could reduce MCAO/R-induced expression of TLR4, TRAF6 and TNF-α, which might be related to the effects of Naoluoxintong in cerebral ischemia injury.

Fast Swept-Wavelength, Low Threshold-Current, Continuous-Wave External Cavity Quantum Cascade Laser.

We present a low threshold-current and fast wavelength-tuning external cavity quantum cascade laser (EC-QCL) using a scanning galvanometer in the Littman-Metcalf cavity geometry. The EC-QCL could repeatedly swept at 100 Hz over its full tuning range of about 290 nm (2105 cm-1 to 2240 cm-1), providing a scan rate of 59.3 µm s-1. The continuous-wave (CW) threshold current of the EC-QCL was as low as 250 mA and the maximum output power was 20.8 mW at 400 mA for a 3-mm-long QCL gain chip. With a sawtooth wave modulation, a scan resolution of < 0.2 cm-1 can be achieved within the tuning range. The low power-consumption and fast swept-wavelength EC-QCL will be beneficial to many applications.

HOX transcript antisense intergenic RNA represses E-cadherin expression by binding to EZH2 in gastric cancer.

AIM: To clarify the mechanisms of HOX transcript antisense intergenic RNA (HOTAIR) in gastric cancer (GC) migration and invasion. METHODS: Quantitative real-time polymerase chain reaction (qPCR) was used to detect the expression level of HOTAIR in GC tissues. The correlation of its expression with clinicopathological features was analyzed. Area under receiver operating characteristic curve (AUCROC) was constructed to evaluate the diagnostic value of HOTAIR. Wound-healing assay and Transwell assay were performed to detect the biological effects of HOTAIR in GC cells. qPCR, western blot and immunohistochemistry were used to evaluate the mRNA and protein expression of E-cadherin. RNA-binding protein immunoprecipitation was used for the analysis of EZH2 interactions with HOTAIR. Chromatin immunoprecipitation assay was performed to investigate direct interactions between EZH2 and E-cadherin. RESULTS: The expression of HOTAIR was up-regulated in GC tumorous tissues compared with the para-tumorous tissues (P < 0.001). Its over-expression was correlated with tumor-node-metastasis (TNM) stage (P = 0.024), tumor invasion (P = 0.018), lymph node metastasis (P = 0.023), and poor prognosis (P < 0.001). Multivariate Cox regression analysis confirmed expression of HOTAIR as an independent predictor of overall survival (P = 0.033), together with TNM stage (P = 0.002) and lymph node metastasis (P = 0.002). The AUCROC was up to 0.709 (95%CI: 0.623-0.785, P < 0.001). Knockdown of HOTAIR by siRNA in GC cells suppressed the migration and invasion of GC cells. Significantly negative correlation between HOTAIR and E-cadherin was found in GC tissues and cell lines, and HOTAIR contributed to the regulation of E-cadherin through binding to EZH2 with the E-cadherin promoter. CONCLUSION: HOTAIR may play a pivotal role in tumor cell migration and invasion. It can be used as a potential diagnostic and prognostic biomarker for GC.

[Clinical observation on the effect of joint mobilization in treating elderly patients after distal radius fractures operation].

OBJECTIVE: To investigate the effect of joint mobilization on postoperative wrist joint function, pain and grip strength for elderly patients with distal radius fracture. METHODS: From January 2015 to June 2016, a total of 67 elderly patients with distal radius fracture were randomly divided into routine exercise group and joint mobilization group. Among them, 37 patients in the routine exercise group underwent conventional distal radius fracture postoperative joint function exercise regimen, including 16 males and 21 females with a mean age of (67.8±3.2) years old ranging from 60 to 72 years old;the injured side was dominant in 23 cases and non-dominant in 14 cases;injury mechanism was fall in 26 cases, traffic accident in 11 cases; for AO type, 6 cases were type B3, 18 cases were type C1, 7 cases were type C2, 6 cases was type C3. Other 30 patients in the joint mobilization group underwent joint mobilization on the basis of the routine exercise group including 14 males and 16 females with a mean age of (67.1±4.0) years old ranging from 61 to 74 years old; the injured side was dominant in 21 cases and non-dominant in 9 cases;injury mechanism was fall in 25 cases, traffic accident in 5 cases;for AO type, 8 cases were type B3, 13 cases were type C1, 6 cases were type C2, 9 cases were type C3. The wrist joint activity, Gartland-Werley wrist joint function score, VAS pain score and grip strength were observed at 3 months afrer treatment. RESULTS: After 3 months' treatment, the VAS in the routine exercise group was higher than that of the joint mobilization group (P<0.05). The grip strength of affected side in both groups were lower than that of contralateral side, but the average grip strength of affected side in joint mobilization group was higher than that in routine exercise group(P<0.05). In routine exercise group, the average angle of flexion, extension, radial deviation were significantly higher than those of joint mobilization group(P<0.05). But ulnar deviation angle in routine exercise group compared with joint mobilization group had no significant difference (P>0.05). In the comparison of each item of Gartland-Werley, there was no significant difference between two groups in residual deformity and complication(P>0.05); the average score of subjective score, objective score and total score in routine exercise group were significantly higher than those of the joint mobilization group (P<0.05). The wrist function Gartland-Werley score in routine exercise group after treatment was excellent in 21 cases, good in 10, 6 in fair, while in joint mobilization group, excellent in 23, good in 6, fair in 1(P<0.05). CONCLUSIONS: The application of joint mobilization in the treatment of elderly patients with distal radius fracture can improve the joint activity and obtain better wrist function after surgery.

High Efficiency, Low Power-Consumption DFB Quantum Cascade Lasers Without Lateral Regrowth.

Very low power-consumption distributed feedback (DFB) quantum cascade lasers (QCLs) at the wavelength around 4.9 µm were fabricated by conventional process without lateral regrowth of InP:Fe or using sidewall grating. Benefitted from the optimized materials and low waveguide loss, very low threshold current density of 0.5 kA/cm2 was obtained for a device with cavity length of 2 mm. Combined with the partial-high-reflection coating, the 1-mm-long DFB QCL achieved low power-consumption continuous wave (CW) operation up to 105 °C. The CW threshold power-consumptions were 0.72 and 0.78 W at 15 and 25 °C, respectively. The maximum CW output power was over 110 mW at 15 °C and still more than 35 mW at 105 °C. At 15 °C, wall-plug efficiency of 5.5% and slope efficiency of 1.8 W/A were deduced, which were very high for low power-consumption DFB QCLs.

Tigecycline targets nonsmall cell lung cancer through inhibition of mitochondrial function.

Nonsmall cell lung cancer (NSCLC) is the most common type of lung cancer with a high mortality rate and still remains therapeutically a challenge. A strategy to target NSCLC is to identify agents that are effective against NSCLC cells while sparing normal cells. We show that tigecycline, an FDA-approved antibiotic drug, preferentially targets NSCLC cells. Tigecycline is effective in inhibiting proliferation and inducing apoptosis of multiple cell lines derived from two common NSCLC subtypes: adenocarcinoma and squamous cell carcinoma. Tigecycline also dose-dependently inhibits colony formation of NSCLC subpopulation of cells with highly proliferative and invasive properties. Compared to NSCLC cells, tigecycline affects proliferation and survival of normal fibroblast cells significantly to a less extent. More importantly, tigecycline significantly inhibits NSCLC tumor growth through decreasing proliferation and increasing apoptosis of tumor cells in vivo. Tigecycline significantly inhibits mitochondrial respiration, mitochondrial membrane potential, and ATP levels and increases reactive oxygen species (ROS), suggesting that tigecycline impairs mitochondrial functions. Our study suggests that tigecycline may be a useful therapeutic agent, and inhibiting mitochondrial functions may represent a new targeted therapy for NSCLC.

Functionalized graphene oxide mediated adriamycin delivery and miR-21 gene silencing to overcome tumor multidrug resistance in vitro.

Multidrug resistance (MDR) is a major impediment to successful cancer chemotherapy. Co-delivery of novel MDR-reversing agents and anticancer drugs to cancer cells holds great promise for cancer treatment. MicroRNA-21 (miR-21) overexpression is associated with the development and progression of MDR in breast cancer, and it is emerging as a novel and promising MDR-reversing target. In this study, a multifunctional nanocomplex, composed of polyethylenimine (PEI)/poly(sodium 4-styrenesulfonates) (PSS)/graphene oxide (GO) and termed PPG, was prepared using the layer-by-layer assembly method to evaluate the reversal effects of PPG as a carrier for adriamycin (ADR) along with miR-21 targeted siRNA (anti-miR-21) in cancer drug resistance. ADR was firstly loaded onto the PPG surface (PPGADR) by physical mixing and anti-miR-21 was sequentially loaded onto PPGADR through electric absorption to form (anti-miR-21)PPGADR. Cell experiments showed that PPG significantly enhanced the accumulation of ADR in MCF-7/ADR cells (an ADR resistant breast cancer cell line) and exhibited much higher cytotoxicity than free ADR, suggesting that PPG could effectively reverse ADR resistance of MCF-7/ADR. Furthermore, the enhanced therapeutic efficacy of PPG could be correlated with effective silencing of miR-21 and with increased accumulation of ADR in drug-resistant tumor cells. The endocytosis study confirmed that PPG could effectively carry drug molecules into cells via the caveolae and clathrin-mediated endocytosis pathways. These results suggest that this PPG could be a potential and efficient non-viral vector for reversing MDR, and the strategy of combining anticancer drugs with miRNA therapy to overcome MDR could be an attractive approach in cancer treatment.

Enhanced brain targeting of curcumin by intranasal administration of a thermosensitive poloxamer hydrogel.

OBJECTIVES: The aim of this study was to develop a curcumin intranasal thermosensitive hydrogel and to improve its brain targeting efficiency. METHODS: The hydrogel gelation temperature, gelation time, drug release and mucociliary toxicity characteristics as well as the nose-to-brain transport in the rat model were evaluated. KEY FINDINGS: The developed nasal hydrogel, composed of Pluronic F127 and Poloxamer 188, had shorter gelation time, longer mucociliary transport time and produced prolonged curcumin retention in the rat nasal cavity at body temperature. The hydrogel release mechanism was diffusion-controlled drug release, evaluated by the dialysis membrane method, but dissolution-controlled release when evaluated by the membraneless method. A mucociliary toxicity study revealed that the hydrogel maintained nasal mucosal integrity until 14 days after application. The drug-targeting efficiencies for the drug in the cerebrum, cerebellum, hippocampus and olfactory bulb after intranasal administration of the curcumin hydrogel were 1.82, 2.05, 2.07 and 1.51 times that after intravenous administration of the curcumin solution injection, respectively, indicating that the hydrogel significantly increased the distribution of curcumin into the rat brain tissue, especially into the cerebellum and hippocampus. CONCLUSIONS: A thermosensitive curcumin nasal gel was developed with favourable gelation, release properties, biological safety and enhanced brain-uptake efficiency.

[Adaptive change of masseter muscle after the ostectomy of mandibular angle in rabbits].

OBJECTIVE: To study the changes of masseter muscle after reducing the mandibular by measuring some relative index after ostectomy of the mandibular angle along arch line. METHODS: Left mandibular angle ostectomy was performed on New Zealand female rabbits aged three months. The right was not operated as control groups. Five rabbits were examined at the following intervals: 2, 4, 8, 12 and 24 weeks. RESULTS: There were remarkable decreases in the experimented masseter muscle masses and the same type muscle fiber areas compared with the control group (P < 0.05). As for the fiber types, a decrease in type I fibers and an increase in type II fibers were noticed on operative side masseters (P <0.05). Sarcomere lengths in the operative side muscles were significantly reduced and showed statistical significance during first 4 weeks (P < 0.05), but there was no difference between the operative group and the control group after 8 weeks (P > 0.05). CONCLUSIONS: The changes of masseter fibres show reconstruction of masseter muscle after mandibular angle ostectomy.

[Application of tissue flaps in repair of limbs injuries].

OBJECTIVE: To summarize and analyze the main point on the reconstruction of traumatic tissue defects of limbs with vascularized skin and multi-tissue flaps. METHODS: Sixty-seven cases of traumatic tissue defects of limbs were reconstructed with 14 kinds of skin or multi-tissue flaps. The operative methods included local transposition, cross-transposition with vessel pedicles and vessel anastomosed free transplantation. RESULTS: Forty cases with vessel anastomosed free transplantation and 26 cases with local or cross-transposition of vessel pedicled flaps were survived. In the followed up cases, 53 cases were satisfied with the outward appearance of the skin flaps. All the cases with bone flap or skin-bone flap resulted in union. And the cases with motor nerve anastomosed myocutaneous flap transplantation had recovered to 2-3 grade muscle contraction ability. CONCLUSION: It is important that the appropriate flaps and operative methods should be chosen according to the size, location, depth and structure of the tissue defects. To raise the success rate and to gain better operation effect, the correct manipulation in operation and the rational postoperative treatment are necessary.